Detection of somatic muscle fasciculation on electrocardiograms. Small discrete spikes appearing on the electrocardiogram (ECG) of a man with a pacemaker turned out to be fasciculation potentials picked up from leg muscles. To find out how common these spikes were all routine ECGs made in one month were reviewed. Spike potentials were found in six patients, and in each case they originated from somatic musculature. Spikes could nearly always be detected on ECGs that were recorded subsequently in patients known to have lower motor neurone lesions that produced fasciculation. Thus the presence of these fasciculation spikes may suggest underlying neuromuscular disease; this possibility should be recognised by those who record ECGs so that the spikes are not suppressed by overuse of the filter.


Failure of phenobarbitone to prevent febrile convulsions. One-hundred-sixty-five children without known neurological disorder who presented with their first febrile convulsion between the ages of six months and three years were assigned to daily phenobarbitone treatment or to a control group and followed up at a special clinic for six months. One-hundred-and-sixty-one-one children completed the trial, and of the 88 children assigned to phenobarbitone treatment 10 had further convulsions during this period compared with 14 of the 73 control children. Only 49 of those assigned to phenobarbitone took the drug regularly throughout the trial, and four of these had further febrile convulsions, a proportion not significantly different from that in the controls. All four had mean plasma phenobarbitone concentrations over 69 mumol/l (16 mug/ml) during the trial and in three the plasma concentration was at or over this figure within eight hours over 69 mumol/l (16 mug/ml) during the trial and in three the plasma concentration was at or over this figure within eight hours of the repeat convulsion. Regular phenobarbitone does not seem to prevent febrile convulsions. Attention should instead be directed to organising emergency services to allow early termination of fevrile  convulsions, whether first or subsequent, to prevent irreversible brain damage.


Medicines and elderly people: a general practice survey. All 151 patients of 75 years and over in one practice were visited at home to survey their health and how they managed their medicines. Altogehter 87% were on regular treatment, 34% taking three or four different drugs each day. Most were responsible for their own drugs and managed them well, but many left their drugs in exposed places and were uncertain about how to dispose of unwanted medicines. Overall they were prescribed about three times the number of drugs prescribed for the general population, and women took twice as many drugs regularly as men. Although many drugs were obtained directly from a pharmacist, his advice was rarely sought. Most were labelled, but more explicit instructions about indications for taking the drug would have been helpful, and information about hoarded drugs would have been enhanced by dispensing  and expiry dates. Treatment was facilitated when patients brought their drugs to the consultation and careful records were made of repeat prescriptions. As so many patients take three or more different types of drugs each day a container in which a day's supply could be laid out would be useful.


Resuscitation teaching room in a district general hospital: concept and practice. Practical training in cardiopulmonary resuscitation presents a problem because of the shortage of teacher time and the many potential trainees. A resuscitation teaching room in district general hospital has been established, equipped with training mannikins and models, together with wall diagrams and cassette recordings. The arrangement enables many trainees to gain training in small groups with minimal demand on teachers. Experience with the room in use has suggested that the concept may have an application in many district general hospitals and possibly also in large industrial concerns.


Coeliac disease with farmers' lung.

Coeliac disease with farmers' lung. Two patients with allergic alveolitis due to mouldy hay antigens (farmer's lung) were shown to have malabsorption due to coeliac disease. As similar associations have been found with other alveolar diseases, this association is probably not fortuitous and further population screening should be done.


Incidence of tuberculosis, hepatitis, brucellosis, and shigellosis in British medical laboratory workers. A retrospective postal survey of 21 000 medical laboratory workers in England and Wales showed 18 new cases of pulmonary tuberculosis in 1971, a five-times increased risk of acquiring the disease compared with the general population. Technicians were at greatest risk, especially if they worked in morbid anatomy departments. Of the 35 cases of hepatitis, the technicians were again the occupational group most likely to acquire the disease. Microbiology staff were twice as likely to report shigellosis as those in other pathology divisions but only one case of brucellosis was reported in the whole laboratory population. A similar survey carried out in 1973 of 3000 Scottish medical laboratory workers corroborates the results from England and Wales. Medical laboratory workers continue to experience a considerable risk of developing an occupationally acquired infection. Improvements in staff safety and health care seem to be necessary.


Papers and originals.

Papers and originals. Six cases of persistent non-accidental poisoning of children by their parents are reported. Certain features may draw attention to the diagnosis, particularly bizarre symptoms and signs with no apparent pathological explanation, and toxicological analysis should be carried out to obtain rapid confirmation of the diagnosis. The underlying disorder may include marital conflict, overinvolvement between parent and child, or drug abuse in the parents. A suggested plan of action for managing this problem is outlined.


Complement and meningococcal infection.

Complement and meningococcal infection. Serum C3 levels were measured in 211 patients with meningococcal disease. Low levels were found in 13 patients with acute meningococcaemia, and complement activation may have contributed to the peripheral circulatory collapse that was responsible for nine deaths. The complement profile of these patients suggested activation of both classical and alternative complement pathways. Patients with meningitis had a higher mean serum C3 level than controls. Serial studies in 13 serum antigen-positive patients with meningitis who subsequently developed arthritis or cutaneous vasculitis showed a transient fall in serum C3 in eight. This fall was probably due to the formation of immune complexes that were responsible for their allergic complications.


Response and survival in advanced breast cancer after two non-cross-resistant combinations. A prospective study with two cytotoxic combinations (cyclophosphamide, methotrexate, and fluorouracil (CMF), and adriamycin plus vincristine (AV)) was carried out in 110 patients with advanced breast cancer. There was no significant difference between the treatment groups in the response rate after primary treatment, the median duration of response, and the median survival. In both groups responders survived for longer than non-responders. Secondary treatment after crossover for progression or relapse resulted in response rates of 35% for AV and 20% for CMF. Toxicity was mainly represented by reversible haemosuppression. These results are comparable with those obtained with other multiple-drug regimens, and combination chemotherapy alone seems to have reached a plateau in its capacity to control disseminated breast cancer.


Rheumatoid arthritis and ankylosing spondylitis occurring together. Rheumatoid arthritis and ankylosing spondylitis are often difficult to differentiate, though it is important to do so as the natural history and treatment of the two conditions differ. Nine patients have recently been seen, each of whom fulfilled the criteria for both rheumatoid arthritis and ankylosing spondylitis. In eight of the nine patients the histocompatibility antigen HLA-27 was present. A possible explanation of these cases is that one of the diseases occurred by chance in patients already suffering from the other, but this is extremely unlikely. If a chance association is not the correct explanation the basic concepts defining rheumatoid arthritis and ankylosing spondylitis must be reconsidered.


False-positive lung scans and radiotherapy. It has been suggested that obliterative vasculitis in the lung might mimic pulmonary embolism on a ventilationperfusion scan. The combined scans of six patients with breast cancer who had undergone radiotherapy to the chest wall, which can induce pulmonary vasculitis, were therefore examined. Eleven of the 12 scans showed perfusion defects with ventilation-perfusion mismatch on the irradiated side. Special care is needed in interpreting the lung scans of patients who have received an appreciable tissue dose of radiation to the lungs; mismatch need not indicate pulmonary embolism.


Horner's syndrome and headache due to carotid artery disease. Horner's syndrome was accompanied by ipsilateral pain in the head, face, or neck in eight patients. In all cases angiography showed narrowing of the internal carotid artery in a pattern compatible with dissection within the arterial wall. In one patient in whom this diagnosis was substantiated by surgical exploration biopsy of the arterial wall showed changes typical of cystic medial necrosis. It is suggested that this clinical presentation constitutes a distinct syndrome.


Twelve-minute walking test for assessing disability in chronic bronchitis. The distance covered in 12 minutes' walking was used to test exercise tolerance in chronic bronchitis. The distance covered bore a poor relation to the forced expiratory volume in 1 second but a significant relation to the forced vital capacity and the maximum oxygen consumption and ventilation on a bicycle ergometer. The test may be a simple practical guide to everyday disability in chronic bronchitis.


Multiple sclerosis among immigrants in Greater London. Among immigrants resident in greater London from Europe, Ireland, the USSR, the old Commonwealth countries of Australia, Canada, and New Zealand, North and South America, Egypt, Turkey, and Iran the incidence of admission to hospital for probable multiple sclerosis (MS) between 1960 and 1972 was high or moderately high. The incidence was the same order as that found in those born in the United Kingdom. Immigrants from India, Pakistan, and other Asian countries and from new Commonwealth Africa and America, which includes the West Indies, had a low incidence of hospital admission for MS. Immigrants from countries where the risk of MS is low whose parents were born in Europe had a reduced incidence of admission to hospital but not the very low incidence found in those parents were also born in these countries. Emigrating to England from low risk parts of the world did not seem to increase the risk of developing MS.


Defects in sphygmomanometers: an important source of error in blood pressure recording. Almost half the sphygmomanometers in a teaching hospital group had defects in the control valve which interfered with accurate blood-pressure reading. Ward staff should be taught to check sphygmomanometers regularly and replace control valves; time consumption and cost are low. The cuffs in general use in these hospitals, and of the standard size sold in Britain, had rubber bags which did not encircle the arm of more than half the patients on whom they were used. This deficiency causes over-reading of blood pressure in obese people. The size of error is uncertain but it should be avoided by adopting a cuff with a longer bag.


Erythema infectiosum: an outbreak of "slapped cheek" disease in north Devon. An outbreak of erythema infectiosum (fifth disease; megalerythema epidemicum) which occurred in a small north Devon town (population 3600) during the spring of 1975 is reported. All fifty-eight cases displayed the diagnostic "slapped cheek" appearance. Virological studies gave disappointingly negative results.


Acute renal failure in tropical Africa.

Acute renal failure in tropical Africa. Between 1972 and 1975, 55 adult patients with acute renal failure were admitted to the renal unit of Korle Bu Hospital. Fourteen patients died, giving an overall death rate of 25%. Massive intravascular haemolysis after a short febrile illness was the commonest cause of acute renal failure. Clinically these patients presented with blackwater fever but in only one could Plasmodium falciparum malaria be confidently diagnosed. In half the patients various bacterial and viral infections (especially typhoid) could be incriminated as causing this blackwater fever syndrome. The incidence of glucose-6-phosphate dehydrogenase deficiency was 22.5%, but we could not confirm the impression of a greater predisposition to acute renal failure in patients with this enzyme defect.


Detection of gonorrhoea in women.

Detection of gonorrhoea in women. A retrospective survey of 210 female patients with gonorrhoea who attended the West London Hospital during 4 months of 1973 showed that nine out of ten were diagnosed by tests taken at the first examination. Ten patients were diagnosed at third or subsequent examinations, but nine of them had defaulted for more than one month before the diagnosis was made, and the tenth gave a clear history of later infection. Three-quarters of the patients came because of known contact with infected males, and less than a quarter of patients who came for this reason were not infected. After one negative post-treatment test, all recurrences were associated with prematurely resumed sexual intercourse or contact with fresh infection. It is concluded that routine repetitive testing is unproductive, and that the tracing of contacts is of paramount importance.


Minocycline hydrochloride (Minocin) as a single-dose oral treatment of uncomplicated gonorrhoea in men. 349 male patients with uncomplicated gonococcal urethritis were treated with a single dose of 300 mg. or 400 mg. minocycline hydrochloride. The lower dose gave a lower failure rate, 3-2 compared with 5-1 per cent., but this difference was not statistically significant. The overall known failure rate of 4-2 per cent. compares most favourably with our previous findings in this area using other drugs of the tetracycline group. The incidence of post-gonococcal urethritis (5-1 per cent.) was also the lowest we have found. The few side-effects reported were comparatively trivial. Because of its high degree of therapeutic efficacy, the relatively lack of side-effects, and the reduced incidence of post-gonococcal urethritis, minocycline hydrochloride should be considered the drug of choice whenever single-dose oral treatment is given in uncomplicated gonorrhoea in men.


Studies on ciliated epithelia of the human genital tract. I. Swelling of the cilia of Fallopian tube epithelium in organ cultures infected with Mycoplasma hominis. Organ cultures of human Fallopian tubes were infected with Mycoplasma hominis. Scanning and transmission electron microscopy revealed swelling of the cilia of the tubal epithelial cells in infected cultures. In some, the entire cilia were swollen; in others, only the tips. Uninfected cultures kept for up to 7 days showed no structural changes in the cilia or other surface structures. M. hominis multiplied in organ cultures, but not in culture medium without tissue. A practical organ culture technique for the preparation of specimens for electron microscopy is described.


Dopaminergic substrates of intracranial self-stimulation in the caudate-putamen. An extensive mapping of the caudate-putamen in rat for intracranial self-stimulation (ICS) site was undertaken to provide addtional support for the role of dopamine in brain-stimulation reward. Eight-seven per cent of the placements in the neostriatum supported ICS, with self-stimulation rates greater than 250/15 min at 56% of these sites. Electrical stimulation also elicited rearing and clonus, and contralateral body turn, both of which varied in magnitude between animals. In a second experiment, animals were prepared with electrodes aimed at the lateral caudateputamen. Those subjects displaying ICS subsequently received 6-hydroxydopamine lesions to the dopamine cell bodies in the substantia nigra pars compacta, either ipsilateral or contralateral to the electrode. The destruction of the dopamine cell bodies attenuated ICS in both groups during the first post-lesion test sessions. However, the rates in the ipsilateral group declined to between 2 and 9% of control scores, whereas the rate in the contralateral group improved over testing to 72% of control values, 28 days after the lesion. On the basis of these data, it was concluded that unilateral destruction of the dopaminergic nigro-neostriatal bundle (NSB) has two effects on ICS behavior. First, unilateral reduction of neostriatal dopamine is accompanied by a loss of brain-stimulation reward at sites normally innervated by the NSB, specifically the caudate-putamen. Secondly, lesions of the NSB produce a general disruption in bar-pressing behavior, as evidenced by the attenuation of ICS following contralateral lesions.


Development of visuomotor behavior in normal and dark-reared cats. The development of visuomotor coordination in light-deprived cats was compared with that of newborn animals, raised under normal circumstances, using behavioral tests. Two groups of light-deprived cats were studied: one of which was dark-reared for 4 months, the other for 7 months. After dark-rearing the cats were kept in animal rooms which were illuminated for 12 h each day. All cats spent at least 4 h each day in a big playroom, where toys were available. Obstacle avoidance, tracking of moving objects, optokinetic nystagmus, visually triggered extension, visually guided placing, visual cliff behavior and jumping were tested. All light-deprived cats revealed a complete recovery of visuomotor behavior; the 7-months deprived cats recovered within 10 weeks and the 4-months deprived ones within 7 weeks. The time period in which the various responses in both groups of light-deprived cats developed after dark-rearing was found to be roughly in accordance with that of normally visually inexperienced kittens after birth.


Acetylcholine release from visual and sensorimotor cortices of conditioned rabbits: the effects of sensory cuing and patterns of responding. A technique was devised for the collection of acetylcholine (ACh) released from the cerebral cortex of awake rabbits while they were performing a previously learned operant task. Based on the assumption that ACh release is directly proportional to the activity of cholinergic synapses under the area of collection, two hypotheses of the functional role of cortical cholinergic mechanisms were examined: (1) that activity in cholinergic neurons is related to the inhibition of responding; (2) that cholinergic activity is related to the perception of a 'significant' stimulus. Five groups trained on different behavioral paradigms were used to test these hypotheses. ACh release was collected concurrently from visual and sensorimotor cortices to differentiate diffuse from specific cortical effects. A small (50-100%) increase in ACh release was found in all groups and from both cortical areas. In the case of one group (visually cued, reinforced for low response rates) a significantly greater increase occurred from sensorimotor cortex only. These findings do not support either hypothesis alone, and are interpreted as evidence for two cholinergic systems within, or projecting to the cortex. One is related to generalized behavioral arousal and desynchronization of the electroencephalogram. Activation of the second cholinergic system is dependent on both response inhibition and the presence of a significant stimulus of the visual (but not of the auditory) modality.


Relation of axon membrane to myelin membrane in sciatic nerve during development: comparison of morphological and chemical parameters. The relationship of axon circumference to myelin area on cross-section both for myelinated and total fibres has been estimated at a mid-point in the sciatic nerve of two rabbits, one newborn and the other 20 weeks old. The slopes of the regression lines relating myelin area to axon circumference for myelinated fibres were 0.72 (standard error 0.03) with a correlation coefficient of 0.81 in the newborn nerve and 2.96 (standard error 0.05) with correlation coefficient of 0.96 in the 20-week nerve. Using the above parameters, and assuming constant thickness of axolemma and constant packing density of myelin, a correlation was made of the change in relationship of axolemma volume of myelinated fibres to myelin volume in the nerve between the two ages with the changes in content of two membrane lipids, ganglioside and cerebroside. This revealed a constant relationship of morphological to chemical parameters at the two ages although the proportion of unmyelinated fibres was much greater in the newborn. If cerebroside is regarded as a marker for myelin membrane, this observation suggests an association of gangliosides with myelination in peripheral nerve.


Regional and subcellular [3h]estradiol localization in selected brain regions and pituitary of female mice: effects of unlabeled estradiol and various anti-hormones. Groups of ovariectomized mice were pretreated for 30 min with either vehicle, unlabeled estradiol benzoate or one of the following anti-hormones: cyproterone acetate, CI-628 or CN-69, 725-27. One hour after an I.V. injection of [3H]estradiol the levels of toluence extractable radioactivity retained in the crude nuclear and cytosol fractions of selected brain regions, pituitary and plasma were determined by liquid scintillation spectrometry. The major findings were: (1) In vehicle treated animals [3H]estradiol uptake in the pituitary greatly exceeded that in all brain regions. Within the brain uptake was greatest in the preoptic anterior hypothalamus (POA-AH) and medial basal hypothalamus (MBH) samples. Nuclear uptake exceeded cytosol uptake only in the pituitary and POA-AH and MBH samples. (2) Estradiol benzoate pretreatment greatly reduced nuclear, and to a lesser extent cytosol [3H]estradiol uptake in pituitary, POA-AH and MBH samples. Estradiol benzoate pretreatment also reduced nuclear uptake in the dorsal middle hypothalamus (DMH). (3) The anti-androgen cyproterone acetate, previously shown to have anti-estrogenic effects in female sexual behavior tests, was found to have no effect on nuclear or cytosol [3H]estradiol uptake in brain and pituitary. (4) The anti-estrogen CI-628 was found to reduce nuclear [3H]estradiol uptake in the POA-AH and pituitary samples. It also reduced cytosol [3H]estradiol uptake in the pituitary sample. The anti-estrogen CN-69, 725-27 produced a much greater inhibition of nuclear [3H]estradiol uptake than CI-628 in the POA-AH, MBH, DMH, dorsal posterior hypothalamus and pituitary samples. This anti-estrogen also reduced cytosol [3H]estradiol uptake in the POA-AH, MBH and pituitary samples. (5) A preliminary chromatographic analysis of vehicle control samples indicated that 70-98% of the nuclear radioactivity in target regions such as POA-AH, MBH and pituitary was iso-polar with authentic estradiol, while less than 50% of the radioactivity in plasma and cortex behaved as estradiol.


An autoradiographic study of gliogenesis in the rat lateral geniculate nucleus (LGN). Rats pregnant for 14, 16, 18 and 20 days, as well as 1-, 3-, 7-, 12-, 16- and 21-day-old offspring, received a single injection of [3H]thymidine and were killed at postnatal ages of 22-27 days. An autoradiographic study of DNA synthesis revealed that proliferation of non-neuronal matrix cell precursors destined for the dorsal part of the lateral geniculate nucleus had already started by gestational day 14. Quantiative evaluation of the incidence of labelled cells revealed 2 peaks occurring in both groups of non-neuronal cells at postnatal days (PD) 7 and 16. It has been assumed that the accelerated production of ectodermally derived glial cells, observed towards PD 7, relfects the enhanced growth of the neuronal surface covered with glial cell processes, and that at PD 16 formation of myelin sheaths. Changes in the number of labelled cells of mesodermal origin in the course of development can probably be attributed to the rate of vasculogenesis of the studied region.


The growth and myelination of central and peripheral segments of ventral motoneurone axons. A quantitative ultrastructural study. This study compares the growth and myelination of those parts of cervical ventral motoneurone axons in the spinal cord (the intramedullary segments) and in the ventral roots of fetal and young rats (up to 21 days postnatal). The same fibre bundles are examined centrally and peripherally. Myelination begins centrally  and peripherally at about birth. However, the peripheral segments of some fibres may begin to become myelinated before the central. Over the first 3 weeks after birth the minimum circumference of peripheral segments of myelinated axons remains relatively constant at 3 mum but that of central segments falls from 2.5 mum to just over 1 mum. Axons within the same fibre bundles tend to be thinner and less heavily myelinated centrally than peripherally. With ageing, axon circumference becomes more strongly correlated with sheath thickness. The thickness of the sheath surrounding an axon of a given circumference does not differ statistically from one age to another or between central and peripheral segments. Studies of myelin sheath growth rate show that in the early stages glial and Schwann cells vary independently of one another in the rates at which they add new turns to sheaths around central and peripheral segments of axons in the same bundles.


Electron microscopic evidence for a transsynaptic migration of tetanus toxin in spinal cord motoneurons: an autoradiographic and morphometric study. Adult rats were injected intramuscularly (musculus deltoideus) with 125I-labeled tetanus toxin. First signs of tetanic rigidity became visible 12-13 h after injection: death occurred 1-2 h later. Electron microscopic autoradiography of the ventrolateral spinal cord gray matter showed a large part of the radioactivity to be located in motoneurons (perikaryon, axon and dendrites) at 7 and 14 h after injection. A great majority of the rest of the label was found over synaptic terminals, most of them were afferent to motoneurons. The percentage of labeled nerve terminals increased significantly (P less than 0.05) between 7 h and 14 h after injection. Glial elements surrounding the motoneurons were mostly unlabeled. These observations strongly favor the assumption of a transsynaptic migration of tetanus toxin. Dorsal root, dorsal horn and cell bodies of spinal cord interneurons were free of label.


Ultrastructure and synaptic contacts in barrels of mouse SI cortex. Barrels in the posteromedial barrel subfield (PMBSF) in layer IV of mouse somatosensory cortex are consistently identifiable and somatotopically related to the large whiskers on the animal's snout32,38. This is a study of the ultrastructure - in particular the synaptic connections - of mouse PMBSF barrels. A technique was developed which enabled the precise selection for electron microscopy of specific regions of barrels identified in the light microscope. Barrel "sides" containing a high density of neuronal cell bodies and myelinated axons, contrasted with barrel "hollows" in which these elements were relatively sparse. The types and frequencies of synapses were examined in series of thin sections through sides and/or hollows of barrels B2, C3, C7, D4, E4, E5, and E8 from 6 mice. In all, 3042 synapses from 20 fields, each at least 10 mum x 10 mum x 4.8 mum in size, were classified. Four distinct kinds of presynaptic terminal were identified: (1) darkly, and (2) lightly stained, asymmetrically synapsing terminals (AD, AL respectively), and (3) darkly, and (4) lightly stained, symmetrically synapsing terminals (SD, SL respectively). Synapses of these terminals were distributed in roughly similar proportions throughout the neuropil of barrel sides and hollows. Thus in all barrel regions approximately 92% of the synapses in neuropil were made by AD terminals, 1.0% by AL, 2.4% by SD and 4.0% by SL terminals.


Synaptic actions of tectofugal pathways on abducens motoneurons in the cat. Organization of pathways between the superior colliculus (CS) and abducens motoneurons (VI-MNs) was studied in cats under pentobarbital anesthesia using intracellular recordings from VI-MNs and adjacent reticular neurons. Latencies of EPSPs elicited by contralateral CS stimulation indicate that a small fraction of the excitatory pathway may be monosynaptic while its major part is disynaptic. As suggested by an analysis of synaptic responses to microstimulation of the paramedian pontine region, excitatory impulses descend in the tectobulbospinal tract after crossing at midbrain levels. An attempt was made to identify interneurons of the excitatory tectoabducens pathway in the region just ventral and rostroventral to the VI-nucleus. About one-quarter of the reticular neurons in this region received monosynaptic excitation specifically from the contralateral CS. They were acceptable as interneurons with regard to other response characteristics too. Axonal projection to, or through, the abducens nucleus was demonstrated for some of them by intranuclear microstimulation or by tracing axons after Procion yellow injections. It is suggested that "premotor" interneurons of the excitatory tectoabducens pathway are concentrated in the vicinity of the abducens nucleic. A similar investigation of inhibitory responses to ipsilateral CS-stimulation indicates that inhibitory pathways are at least disynaptic and, for the most part, contain three or more synapses. In its initial trajectory the inhibitory pathway appears to be identical with the tectobulbospinal tract,but it decussates for the second time at caudal pontine levels to reach ipsilateral VI-MNs.


EEG development in normal and undernourished rats. The development of EEG was studied in normal and undernourished white and black hooded rats, aged 9-30 days. Undernutrition of the young was accomplished by underfeeding the mothers with restricted amounts of a standard laboratory food from the 7th day after conception until the 21st day after birth. Bipolar EEG recordings were made from the sensorimotor cortex and from the visual cortex in rats with chronically implanted electrodes. The EEG was recorded, stored on magnetic tape and analyzed for amplitude distributions and frequency spectra. During the recording 3 behavioural states (defined on the basis of behavioural criteria) were distinguished.


Somatotopic localization in cat motor cortex. Punctate intracortical stimulation of the motor cortex (areas 4 and 6), with parallel observation of the induced movements, permits description of a fine somatotopic organization of the motor control areas for different parts of the musculature in freely moving adult cats. The results show that movements produced by electrical stimulation of the motor cortex are always single and non-repetitive, regardless of the duration and intensity of the stimulation. These movements are restricted to a very precise part of the musculature, and experiments show that this localization is related to the exact position of the tip of the stimulating electrode in the motor cortex. Other experimental data show that motor responses which disturb the animal's equilibrium are accompanied by postural adjustments. Stimulation of the cerebral cortex permits the definition of a separate motor control area for each part of the cat musculature, with an individual control area for each of the joints of the forelimb. This was not possible for the hindlimb, which is always activated in its entirety. These results establish a new representation of the somatotopic organization of the cat motor cortex. This diagram shows that area 6 controls the more axial parts of the musculature, while area 4 controls the proximal and distal parts of the limb muscles. This map was compared to numerous previous data on the somatotopic organization in the cat motor cortex, especially to the map of Woolsey.


Isolation of dendrodendritic synapses from swine olfactory bulbs. Dendrodendritic synapses from swine olfactory bulbs were isolated by homogenization of the gray layer, followed by centrifugation at 1000 X g. Centrifugation of the supernatant at 10,000 X g revealed that all dendrodendritic synapses had pelleted at 1000 X g. The upper portion of the 1000 X g pellet was further purified in a discontinuous sucrose gradient, and each resultant fraction was examined by electron microscopy. The dendrodendritic synapses band below the 1.2-1.4 M sucrose interface, appear to be minimally contaminated with other membranous elements, and have retained their adhesions. The banding pattern and relative amounts of proteins from dendrodendritic synaptosomes were very similar to those of axonal synaptosomes as determined by electrophoresis on polyacrylamide gels containing sodium dodecyl sulfate (SDS) and 8 M urea.


A microelectrode study of amygdaloid afferents: temporal neocortical inputs. Acute experiments were performed on anesthetized cats using standard techniques of electrical stimulation and single unit recording in order to study the responses of amygdaloid neurons to neocortical inputs. Satisfactory records were obtained from 272 amygdaloid neurons. The majority of those fired spontaneously, at low rates, with single, randomly occurring spikes. The lateral neocortex, particularly the portion which is homologous to temporo-insular cortex in man, is capable of influencing the discharges of many amygdaloid neurons. The typical response pattern consisted of an excitatory-inhibitory sequence with the median onset latency of 12.0 msec, which is consistent with monosynaptic excitation of the output-type nerve cells in the affected regions of the amygdala (Al, Ac, Ab). There was an absence of clear topographical arrangement: all of the effective neocortical areas influenced the neuronal discharges in Al, Ac and Ab fairly equally. These results correlate well with neuroanatomical studies of amygdaloid structure and connectivity. Our finding of diffuse non-topographic excitatory influence upon the lateral, central and basal amygdaloid nuclei exerted by insular-temporal regions known to be involved with higher order sensory analysis and pattern recognition is quite consistent with a view of this system serving as a link between neocortical information stores and the fundamental motivational drive mechanisms of the hypothalamus.


Excitatory effects of 5-hydroxytryptamine, histamine and potassium ions on muscular group IV afferent units: a comparison with bradykinin. The excitation of muscular group IV afferent units by the pain-producing substances 5-hydroxytryptamine (5-HT), histamine, and potassium ions was studied in cats and compared with the bradykinin effects of an earlier investigation. The substances were injected into the sural artery and the action potentials of single group IV afferent fibres from the gastrocnemius-soleus muscle were recorded extracellularly. About half of the 180 units tested with chemical stimulation could be excited by amounts of the above agents which are likely to be present in pathologically altered tissues. Of the tested substances, 5-HT was the most and potassium the least effective stimulant; in comparison with bradykinin, 5-HT was by far less potent, though. The molar ratios of approximately equivalent doses of bradykinin, 5-HT, histamine, and potassium were found to be about 1:30:66:4000. The threshold injection doses of KC1 for activation of muscular group IV units were such that an unspecific depolarizaing mode of action seems probable. Differences in the chemosensitivity of individual group IV units might be indicative of the existence of different receptor sites at the nerve endings. The sensitivity of muscle receptors with group IV afferent fibres to pain-producing substances--especially to bradykinin and 5-HT--supports the view that these units might participate in the mediation of muscle pain.


GDEE  antagonism of iontophoretic amino acid excitations in the intact hippocampus and in the hippocampal slice preparation. Glutamic acid diethylester (GDEE) reversibly antagonized excitations produced by glutamate and aspartate but not those produced by acetylcholine when applied iontophoretically to rat CA1 hippocampal neurons in penthrane (methoxyfluorane) anesthetized rats and to CA1 neurons in in vitro slice preparations. GDEE did not appear to differentiate between the excitations produced by glutamate aspartate and appeared to be a more potent antagonist than has previously been reported. CA1 cells were remarkably sensitive to acetylcholine; 5-50 nA being sufficient to produce marked amino acid-like excitations, which were unrelated to the pH of the acetylcholine. The nature of the responses to applied substances was virtually identical between the intact animal and the in vitro slice preparation. A description of the in vitro technique is given as an Appendix.


Motor and behavioral responses obtained by stimulation with chronic electrodes of the optic lobe of Sepia officinalis. A new technique using a stimulating chronically-implanted electrode has allowed us to study the motor responses induced by electrical stimulation of the optic lobe in a freely swimming Sepia. Electrical stimulation of the cortex of the optic lobe produces no motor response; this is in agreement with the results of preceding authors. The stimulation of the neuropil of the optic lobe by monopolar electrode produces many different motor responses, in support of Boycott's results  obtained by the same type of excitation in acute experiments. However, the field of stimulation of these electrodes could not always have been the same and it is possible that we were sometimes stimulating nervous structures close to the optic lobe. Stimulation by a bipolar electrode, however, which does not have this advantage, induces only two very different motor responses: an ipsilateral rotation and an 'alarm reaction", so called because of its similarities to the 'attentive immobilization" of higher vertebrates. These two reactions are very complex and their different components are linked together as in a behavioural response from an intact animal. These reactions present very different characteristics of excitability. They are obtained from many areas in the neuropil of the optic lobe, within which there does not seem to be any preferential localization. These results emphasize the importance of the optic lobe in motor control.


Using arousal changes in the EEG to indicate gustatory sensitivity following brain lesion in Gallus domesticus. The EEG of Gallus domesticus was recorded before and after brain lesions following stimulation with light, sound and taste. 2. It was found that under the conditions of the experiment the lesions did not have any general effect on the arousal mechanism of the animal. 3. Bilateral lesions in the stratum cellulare externum of one animal had a specific effect on the arousal response to a quinine hydrochloride solution and it was concluded that it is possible to indicate deficits following brain lesion in the gustatory system using the EEG.


Requirements of the young turkey for sulphur amino acids and threonine: comparison with other species. 1. The requirements of the 3-week-old turkey for the sulphur containing amino acids and for threonine were estimated to be 0.83% and 0.94% respectively in diets containing 12.5 MJ ME/kg. 2. It is suggested that the growth responses of rats and slow-growing chicks and of fast-growing chicks and young turkeys to daily intakes of the sulphur containing amino acids and of threonine are similar.


The effects of progesterone on oviposition and ovulation in the domestic fowl (Gallus domesticus). 1. Following an injection of 0.5 or 0.1 mg progesterone/kg between 0 and 6 h after ovulation, oviposition of the resulting egg was delayed by 1 to 11 h and occurred 26 to 31 h after injection, depending on the dose. The injection terminated the laying of a sequence of eggs by causing the next ovulation to occur a day late. The delayed ovulation occurred at the time normally expected for the first ovulation a sequence and became the first of a new sequence. 2. Following an injection of 0.5 or 0.1 mg progesterone/kg between 6 and 15 h after ovulation, oviposition of the resulting egg was generally delayed by between 15 and 28 h and occurred at the same time of day as the next ovulation, which was delayed as in the first experimental situation. Subsequent ovulations were resynchronised and followed at intervals according to the normal sequence established before the injection. 3. Injection of 0.5, 0.1 or 0.05 mg progesterone/kg between 12 and 9 h before expected ovulation advanced the oviposition of the egg already in the uterus (shell gland) by about 3 h. The succeeding ovulation was either advanced or blocked. 4. These observations suggest that the pre-ovulatory surge of progesterone is directly or indirectly involved in the timing of oviposition and ovulation.


The effect of continuous ultraviolet irradiation on broiler chickens. 1. Continuous ultraviolet irradiation (10.45 muW/cm2) did not affect the growth or food conversion efficiency of broilers. 2. The cornea of the eye was roughened by the treatment and there was a loss of the regular arrangement of the corneal cells: vision was not significantly affected after 49 d exposure.


Studies on the dilution of turkey semen. 1. A series of experiments were conducted to determine the effect of diluent, holding temperature and dilution rate on the viability of turkey semen. 2. No significant difference was observed in the fertility of the undiluted controls and semen diluted with Lake's solution to a final rate of 1:4 and maintained at 25 degrees C or 5 degrees C for 30 min. Under these conditions as few as 25 million sperm per weekly insemination were needed for optimum fertility. 3. Turkey semen exhibited the typical "dilution effect", increased respiration with a corresponding decline in fertilising capacity, when diluted at rates of 1 : 8 and 1 : 12.


Renal function changes in laying hens fed on dried poultry manure. 1. Renal function was studied in laying hens which had been fed on diets containing 0 (controls), 10 or 20% dried poultry manure (DPM) for one year. 2. Birds fed on 20% DPM showed increased rates of effective renal plasma flow and increased renal tubular secretion of urate during the infusion of large amounts of urate. 3. Renal hypertrophy was not detected in any group.


Inbreeding components of body weight and growth rate in Japanese Quail. 1. The parental inbreeding component of body weight and daily gain was partitioned into paternal and maternal inbreeding components and the latter were found to be the mor important. 2. The contribution of the maternal inbreeding to the depression of characters was more pronounced on 1-d-old chicks, but declined as the chicks grew. 3. The body weight taken near sexual maturity showed a low and non-significant decline. 4. In spite of differences in the body weight of the two populations of Japanese quail the inbreeding components were similar.


Effect of dietary palmitic acid on broiler chicks fed on various concentrations of calcium. 1. The effect of dietary palmitic acid on body weight and bone-ash of chicks fed three concentrations of calcium was studied in a 2 X 3 factorial design (0 and 10% palmitic acid, 0.4, 0.7 and 1.0% calcium). 2. Body weight of chick not influenced by the calcium concentration when palmitic acid was not included in the diet. 3. When 10% palmitic acid was included the body weight of chicks fed 0.4 and 0.7% calcium was lower (P less than 0.01) than for the other groups. 4. Bone-ash was lower (P less than 0.01) for chicks fed 0.4% calcium than for the other two calcium concentrations when palmitic acid was not added and palmitic acid at 10% of the diet reduced bone-ash of the chicks fed 0.4 and 0.7% calcium (P less than 0.01).


A new method for calculating the accretion rate of bone calcium and some observations on the suitability of strontium-85 as a tracer for bone calcium. 1. A new method for calculating the accretion rate (A) of bone calcium is proposed, based on an impulse analysis of 47Ca data. The method is free of most of the assumptions inherent in previous methods of analysis and appears to give more accurate estimates. 2. In fourteen normal subjects and twelve patients with metabolic bone disease, measurements of A by the new method gave very similar results to the mineralization rate calculated by the method of Burkinshaw et al. (1969). Analysis of twelve studies performed by Neer et al. (1967) gave good agreement with their five compartment model. A close relation between A and Marshall's (1964) A5 was observed, but the latter gave systematically higher results. 3. In sixteen studies both 47Ca and 85Sr were injected simultaneously. Although there were no systematic differences between the values of A for the two tracers, the differences between individual values were greater than the known experimental errors.


The blood: bone disequilibrium. I. The active accumulation of K+ into the bone extracellular fluid. The role of periosteal and endosteal cellular envelopes in the control of the K+ and Na+ content of embryonic chick calvaria was investigated. Data have been presented which suggest that the K+ in extracellular fluid of calvaria may be under a direct membrane control similar to the pump-leak systems hypothesized for most cells. Based on DNA and K+ analysis of cell water, volume and DNA content, the K+ in the bone extracellular fluid was calculated to account for 75% of the total K+ content of intact calvaria. The bulk of K+ is therefore extracellular and its accumulation there was found to be sensitive to the presence of ouabain, iodoacetate, CCCP, and to temperature. Losses of 70% of calvaria K+ were found one hour after addition of 250 muM ouabain. If the exposure to ouabain was brief, the K+ loss was partially reversed. The rate of 42K+ uptake was found to be depressed by ouabain, decreased pH, and La2+. The total Na+ content of these calvaria was found not to vary when incubated with ouabain, iodoacetate, or CCCP.


The blood: bone disequilibrium. II. Evidence against the active accumulation of calcium or phosphate into the bone extracellular fluid. An attempt was made to quantitate in vitro the unidirectional fluxes of Ca2+ and Pi across periosteal and endosteal membranes of frontal bones from calvaria of 20 day chick embryos. The influx of Ca2+, as previously reported, seemed to be passive [12]. The uncoupler, CCCP, had no effect on the influx of Ca2+, but increased both the endosteal and periosteal effluxes. La2+ decreased the influx of Ca2+. The influx of phosphate was also passive and proportional to the concentration of phosphate. The influx was unaffected by either iodoacetate or CCCP, but increased when the periosteal and endosteal membranes were removed; the efflux of phosphate was greater from the endosteal side and was unaffected by CCCP, while iodoacetate increased both the periosteal and endosteal effluxes. The evidence presented refutes the generally accepted hypothesis that Ca2+ (or phosphate) fluxes into and out of bone are governed by a pumpleak system. However, the increase in rate of influx when the cellular layers are removed indicates that the periosteum and endosteum constitute an important structural conponent in the maintenance of bone mineral and its equilibration with the circulation.


Effects of calcitonin and ultimobranchialectomy (UBX) on calcium and bone metabolism in the eel, Anguilla anguilla L. Prolonged administration of synthetic salmon calcitonin (SCT) to immature female silver eels, maintained in sea water, provoked a decrease of the serum calcium concentration and an increase of both the osteoblastic apposition and of the degree of mineralization of the intercellular matrix in the vertebral bone. The osteoclastic resorption and osteocytic osteolysis were not significantly affected, however the osteoclastic index was reduced. The ultimobranchial body, site of CT secretion, was cauterized in immature female silver eels maintained in Ca++ rich tap water. This operation resulted in a rise in serum calcium levels with a maximal response after two weeks. After UBX, the vertebral bone osteoblastic apposition stopped completely but the osteoclastic resorption was not modified. The degree of osteocytic osteolysis did not vary. We also observed a significant decrease in the degree of mineralization of the bone organic matrix. The observations made after UBX confirm those obtained after exogenous CT treatment. SCT administered preventively to immature female eels (maintained in sea water), before experimental maturation, inhibited, at least partially, the acute osteoclastic resorption and completely inhibited the bone demineralization induced by carp pituitary extract. The increase of osteocytic ostelysis, usually observed, did not appear.


The total luminescence of bovine and human dental enamel. The corrected emission and excitation spectra of human and bovine dental enamel and its separated organic material were determined at room temperature and liquid nitrogen temperature. In both materials three distinct luminescence peaks were found in the region 350-360 nm, 405-410 nm, 440-450 nm. The intensity ratios of the peaks of the enamel do not differ substantially upon removal of the inorganic component. Hence a conclusion is confirmed that the organic component is the most responsible material for the total luminescence of the enamel. Several hypothesis are available for determination of the nature of luminescence of the organic components. Differences in the excitation spectra are discussed. Phosphorescence emission and phosphorescence lifetimes were determined.


Comparison of whole calvarial bones and long bones during early growth in rats. II. Turnover of calcified and uncalcified collagen masses. The increase of total collagen and its destruction were compared for whole calvaria and long bones from young growing rats prelabeled in utero with 3H-L-proline. Rats were compared from birth to 16 weeks of age. Long bones and calvaria were isolated as intact anatomical units for autoradiography or separated by collagenase into calified and uncalcified collagens. Autoradiography using 14C-L-proline demonstrated eccentric modeling of bone collagen. With growth the mass of calcified collagen (bone) increased rapidly in calvaria and long bones. A similar increase in the mass of uncalcified collagen (mainly cartilage) occured in the long bones; a very small increase occurred in the fibrous tissue of calvaria. Total and specific radioactivities of collagens at each age were compared to that present at birth. With growth remodeling an almost complete loss of pre-existing radioactive collagen occurred from uncalcified fibrous tissue of calvaria as compared to a smaller but substantial loss from the uncalcified cartilage of long bones. A marked loss of calcifed collagen occurred in long bones as compared to a smaller loss from calvarial bones. The istopic data indicate a large turnover of fibrous tissue (type I collagen) with growth remodeling as compared to a smaller turnover of bone (calcified, type I collagen) and cartilage (typc I collagen). The turnover rate of skeletal collagens depends upon whether the collagen is calcified or not, and not upon the type of collagen.


Concurrent exchange of 45Ca and 3H-tetracycline from rat bone in vitro. Bone from rats sacrified at 2, 5, and 95 weeks of age following 45Ca and 3H-tetracycline labeling in utero or postnatally was placed in solutions of physiological saline, nonradioactive calcium, or tetracycline. This procedure was designed to determine the availability for exchange of 45Ca and 3H-tetracycline from bone mineral in vitro. With time after labeling a gradual decrease occurred in both the nonspecific loss and specific exchange of 45Ca and 3H-tetracycline. 45Ca and 3H-tetracycline in bone could be partially exchanged in vitro with their respective nonradioactive counterparts. Each isotope could be partially exchanged, independently of the other istope. Nonradioactive calcium increased the exchange of 45Ca while suppressing the release of 3H-tetracycline. Molecular 3H-tetracycline exchange occurred to a greater degree than ionic 45Ca exchange and was associated with a small loss of 45Ca. The molecular exchange of 3H-tetracycline with bulk tetracycline did not induce any significant loss of tritium from 3H-tetracycline.


Factors affecting the distribution of zinc in the human skeleton. The zinc content of trabecular and cortical bone was measured in 28 femora obtained at autopsy. The ratios of calcium to zinc, phosphorus and magnesium were determined and their relation to age and vertebral density was investigated. The calcium/zinc ration was significantly higher in cortical as opposed to trabecular bone, whereas the calcium/phosphorus ratios were similar. There was a significant decrease in the calcium/zinc ratios of both trabecular and cortical bone with age and the former was directly related to vertebral density. The calcium/phosphorus ratios of trabecular and cortical bone did not vary significantly with age or vertebral density. Magnesium/zinc ratios tended to parallel the calcium/zinc ratios. The calcium/magnesium ratios were significantly higher in cortical as opposed to trabecular bone. None of these ratios appeared to be affected by the sex of the subject. These findings suggest that changes in skeletal zinc content with age are related to alterations in bone morphology, and that osteoporosis in man develops in association with zinc accumulation rather than zinc deficiency.


The capacity of pig articular cartilage in organ culture to regenerate after breakdown induced by complement-sufficient antiserum to pig erythrocytes. Explants of pig articular cartilage including invading marrow and subchondral bone (together='invasion zone') were cultivated for 10 or 14 days in complement-sufficient rabbit antiserum to pig erythrocytes (AS+C'), and then transferred to heat-inactivated normal rabbit serum (NRS) for a period of recovery. In AS+C' the cartilage matrix lost first proteoglycan and then collagen, but the cells remained viable. The degradation of collagen was accompanied by a fibroblastic transformation of the chodrocytes, first seen in the region immediately above the invasion zone. Immunohistochemical studies showed that after cultivation in AS+C', IgG antibodies entered areas in which the matrix was depleted of proteoglycan and reacted strongly with the majority of chondrocytes; those that had under-gone fibroblastic transformation exhibited little or no reaction. The degree of recovery in NRS depended on the extent to which the matrix had broken down in AS+C'. If degradation of collagen was confined to the region immediately above the invasion zone, and elsewhere only proteoglycan had been lost, new metachromatic material was regenerated in the non-calcified cartilage, and the fibroblast-like chondrocytes resumed their normal appearance and regained their reactivity with the IgG antibodies of AS; new cartilage and chondroid tissue appeared in the cavities of the invasion zone. If degradation of collagen and fibroblastic transformation of chondrocytes had spread throughout the cartilage, breakdown continued in NRS and cartilage disappeared completely above the invasion zone; new cartilage waw sometimes formed in the cavities of the invasione zone.


The distribution of cortical and trabecular bone mass along the lengths of the radius and ulna and the implications for in vivo bone mass measurements. The amounts of cortical and trabecular bone mineral mass were measured by means of microdissection and an ashing technique at approximately 2.5 mm intervals along the most distal 12 cm of radii and ulnae from four women aged 21, 43, 63, and 85. The data show that the distributions of mineral mass and percentage of trabecular bone are similar in both bones. At sites in the radius and ulna commonly used in the photon absorptiometric method of bone mineral mass measurement the percentage of trabecular bone varies between 10% and 50%. The percentage of trabecular bone in the most distal 10% of the length of the radius and ulna remains approximately constant with age but the percentage in the segment which lies between 30% and 40% of the length, measured from the styloid process, increases with age.


The alteration of osteoclast morphology by diphosphonates in bone organ culture. Two diphosphonates alter the morphology of the osteoclast, as they inhibit the calcium45 release from bones stimulated to resorb by lipopolysaccharide. Disodium dichloromethylene diphosphonate was more potent than disodium ethane-1-hydroxy-1, 1-diphosphonate in both inhibiting 45calium release and altering osteoclast morphology. Alteration in the morphology of osteoclasts is associated with little or no change in the morphology of the surrounding non-osteoclast cells. These results indicate a specific morphological effect of diphosphonates on osteoclasts.


Rib structure and bending strength: an autopsy study. Mechanical rib testing and geometric analysis were explored as means of evaluating metabolic bone disease. Seventy-nine male patients were examined postmortem. Displacement rate at the loading point and patient age were important variables for which results had to be corrected. Like long bones, ribs apparently undergo progressive circumendosteal resorption with advancing age but unlike long bones, they show no evidence of continued subperiosteal apposition. Effects of selected individual diseases and of all diseases grouped by major organ system were analyzed. Most produced no discernible modification of rib volume, geometry or bending strength as quantified by modulus of rupture. Exceptions were myeloma and arthritis, where the bony material was weakened without remodeling or loss in volume.


The interaction of supersaturated calcium phosphate solutions with apatitic substrates. The in vitro formation of calcium phosphates from supersaturated solutions seeded with apatite was examined. Reaction kinetics were followed by monitoring solution Ca, Mg, and PO4. Seeds and reaction products were examined chemically and by X-ray diffraction and electron microscopy. Under conditions where amorphous calcium phosphate (ACP) normally precipitates spontaneously, apatite reduced the amount of free ACP formed with a considerable fraction of the Ca and PO4 initially removed from solution depositing directly onto the seeds. At sufficiently great seed concentrations all initial solution losses occurred by this latter route with no free ACP precipitating. These initial events were followed by seed-induced formation of new apatite crystals accompanied by further losses in solution Ca and PO4. Supersaturated solutions stable to spontaneous ACP formation underwent similar losses in solution Ca and PO4 when seeded with apatite. Initial decrease in these ions was instantaneous and proportional to the seed concentration. Subsequent ion removal exponentially decreased with time and correlated with the formation of new apatite crystals overlaying the original seeds. In seeding experiments using physiologically-balanced salt solutions, the initial deposit formed on the seed surface was a magnesium stabilized calcium carbonate phosphate phase. This stable surface phase did not prevent the secondary crystallization of apatite from occurring.


Biosynthesis of diacylglycerols by rat intestinal mucosa in vivo. The biosynthesis of diacylglycerols was studied in rat intestinal mucosa during in vivo absorption of a low molecular weight fraction fraction of butter oil and of the corresponding medium and long chain fatty acids. The experimental fat solutions were given by stomach tube to the animals after a 24-h fast and mucosal scraping were collected 3 h later. The lipids were isolated and the acylclycerols determined by combined thin-layer chromatography gas-liquid chromatography techniques and stereospecific analyses. Free fatty acid feeding led mainly to sn-1,2-diacyl-glycerols, which contained exogenous and endogenous fatty acids. During triacylglycerol feeding, both sn-1,2-and sn-2,3-diacylglycerols were recovered in significant amounts from the intestinal mucosa. The composition of the sn-2,3-diacylglycerols corresponded to that with exogenous fatty acids but the sn-1,2-diacylglycerols clearly contained both exogenous and endogenous fatty acids. In all cases it was possible to isolate endogenous sn-1,2-diacylglycerols made up largely of species with linoleic and arachidonic acids in the 2 position and palmitic and stearic acids in the 1 position, which apparently were not converted to triacylglycerols. The in vivo reacylation of 2-monoacylglycerols via both sn-1,2- and sn-2,3-diacylglycerols is in agreement with similar findings in vitro with everted sacs of rat intestinal mucosa.


Biosynthesis of triacylglycerols by rat intestinal mucosa in vivo. The structure of mucosal triacylglycerols was studied in rat intestinal mucosa in vivo during the absorption of a low molecular weight fraction of butter oil and of the corresponding free fatty acids of medium and long chain length. The mucosal lipids were isolated by solvent extraction and the acylglycerol structures were determined by combined AgNO3- thin-layer chromatography and gas-liquid chromatography techniques and stereospecific analysis. Evidence was obtained for a rapid biosynthesis of triacylglycerols from diacylglycerols arising from the operation of both the monoacylglycerol and the phosphatidic acid biosynthetic pathways. Both sn-1,2- and sn-2,3-diacylglycerols appeared to be converted to triacylglycerols at significant rates, but a preferential utilization of sn-1,2-diacylglycerols could not be excluded. Endogenous dilution varied from a miniumum of 5% during triacylglycerol biosynthesis from monoacylglycerols to 15% during their synthesis from free fatty acids, and was characterized by a preferential placement of the endogenous acids in the sn-3 and 2 positions of the triacylglycerol molecules. Exogenous myristic acid was preferentially associated with the sn-3 position, and stearic acid became preferentially bound to the sn-1 position. The complexity of the triacylglycerol end products prevented an exact estimate of the contribution of the phosphatidic acid pathway, but the acylglycerol structures were compatible with a minimum of 20% of total triacylglycerol yield at all times.


Mitochondria with impaired phosphate transport: 32P uptake studies. Rat liver mitochondria which have been exposed to 0.15 M NaC1 at 35 degrees C for 15 min subsequently take up 32Pi from an external medium only to about 5% of the extent of uptake by control mitochondria. The volume into which 32Pi distributes in a pellet of such "aged" mitochondia is less than that available to 3H2O but is greater than that available to [3H]sucrose. Mitochondria treated in this manner cannot therefore accumulate Pi although limited penetration of the inner membrane can occur. These results confirm earlier findings by indirect methods (Williams, G. R. & Orr, J. L.: Dynamics of energy-transducing membranes (Ernster, L., Estabrook, R. W. & Slater, E. C., eds), Elsevier Scientific Publishing Company, Amsterdam, Netherlands, pp. 497-508 (1974).


Effect of palmitoyl-CoA and beta-oxidation of fatty acids on the kinetics of mitochondrial citrate transporter. The kinetics of the hepatic mitochondrial citrate transporter were studied using 1,2,3-benzene tricarboxylate and the inhibitor-stop technique at 8 degrees C. The apparent Km for this transporter was 250 muM and the maximum velocity was 2 nmol of citrate transported per minute per milligram of mitochondrial protein. This apparent Km was increased when hepatic mitochondria were preincubated with both L-palmitoylcarnitine and CoA-SH but not with either alone. This rise in apparent Km was accompanied by a rise in the acid insoluble CoA-SH content. Removal of mitochondrial acid insoluble CoA by "defatted albumin" resulted in a parallel decrease in the apparent Km. The apparent Km for the citrate transporter was increased after coupled beta-oxidation of L-palmitoylcarnitine or octanoate without a detectable increase in acid insoluble CoA. Inhibition of beta-oxidation of L-palmitoylcarnitine by the D-derivative prevented the rise in the apparent Km. Preincubation with ATP resulted in an increase in this apparent Km. When L-palmitoylcarnitine oxidation occurred without ATP accumulation (hexokinase, glucose, ADP, and inorganic phosphate) the apparent Km for the citrate transporter increased two- to threefold. Therefore, the apparent Km for the citrate transporter varied directly with the acid insoluble CoA content. In addition, this Km was increased as a result of beta-oxidation of fatty acids but the mechanism was not solely attributable to a rise in acid insoluble CoA or ATP. The physiological implications of these findings are discussed.


Pyrimidine reducing enzymes of rat liver. Dihydrouracil dehydrogenase (NADP+) (EC 1.3.1.2) was partially purified from the cytosol fraction of rat liver and fractionated by disc gel electrophoresis. A major and minor band were visualized by staining for enzyme activity. The substrate specificity of these bands was investigated. It was found that both bands were two to three times more active with dihydrothymine as substrate than with dihydrouracil in the presence of NADP+ and the optimum pH of 7.4. Mitochondrial fractions containing most of the NADH-dependent uracil reductase of rat liver cells were fractionated by centrifugation in sucrose density gradients. Two procedures involving linear or discontinuous gradients were used. By both, good separation of NADH- and NADPH- dependent reductases was achieved. Marker enzyme studies supported the view that the NADH-dependent enzyme is located principally in mitochondria whereas the NADPH-dependent enzyme is mainly in plasma and endoplasmic reticulum membranes. For the NADH-dependent reductase the apparent Km for thymine at pH 7.4 was 1.39 times that found for uracil whereas for the NADPH-dependent enzyme the apparent Km values were similar for the two substrates at this pH. Dihydrouracil was the principal product isolated by paper chromatography from the reaction mixture containing a partially purified fraction of mitochondria, uracil and NADH at pH 7.4. This fraction also catalyzed the formation of radioactive carbon dioxide from [2-14C]uracil. The proportion of CO2 formed by the mitochondria was about 10% of that formed by the original homogenate.


The specific  activity of aldolase in the livers of old and young rats. The catalytic activity of liver fructose-biphosphate aldolase (EC 4.1.2.13) of young and old rats in units per manomole sequence has been calculated. No evidence of the accumulation with age of altered enzyme molecules of low catalytic activity was obtained. This is contrary to results obtained using mice and rabbits and indicates that the accumulation of altered enzymes may not always be associated with aging. The possibility that altered proteins are formed, but do not accumulate, cannot be ruled out.


Molecular weight of an extremely hydrophobic protein, zein, in dimethylformamide and in formamide. Both alpha zein purified from a commericial preparation and beta zein prepared fresh from corn are soluble in the nonaqueous solvents formamide and dimethylformamide; in this regard zein resembles water soluble proteins such as insulin, ribonuclease, and lysozyme. On the basis of osmotic pressure measurements made in both formamide and dimethylformamide, alpha zein has a number average moleular weight of 21000-24000 daltons and shows no tendency to aggregate or dissociate. Beta zein exists in an aggregated state (dimer and higher forms) in dimethylformamide. Formamide dissociates the beta zein dimer into monomer units but aggregation to higher species occurs with increasing protein concentration.


The metabolism of higher chlorinated benzene isomers. The metabolism of the isomeric tri- and tetrachlorobenzene isomers, penta- and hexachlorobenzene was investigated in the rabbit. The major urinary metabolites of the isomeric tri- and tetrachlorobenzenes were identified as the corresponding tri- and tetrachlorophenols whose structures were confirmed by chromatographic analyses. The genesis of the formation of metabolites is discussed in terms of their possible arene oxide intermediates in which the NIH shift of a chlorine atom is observed in the oxidation of many of the isomers. Pentachlorobenzene is metabolized to give both pentachlorophenol and a dechlorination-hydroxylation product which was identified as 2,3,4,5-tetrachlorophenol. The hexachlorobenzene substrate did not give any phenolic metabolites.


The mechanism of the degradation of DNA by streptonigrin. The production of single strand cleavage in covalently-closed circular-DNA by the antitumour agent streptonigrin (reduced in situ by NADH) is demonstrated using the ethidium bromide fluorescence assay described previously. The degradation dependent on oxygen is completely inhibited by superoxide dismutase (EC 1.15.1.1) suggesting the intermediacy of the superoxide radical anion in the degradation. However similar complete inhibition of DNA strand breakage by catalase (EC 1.11.1.6) indicates that the hydroxyl radical (formed by interaction of superoxide with hydrogen peroxide) is the primary reactive species. Cupric ion stimulates the cleavage reaction and cobaltous ion has no effect in keeping with model studies using quinolinequinones.


The influence of hydrocortisone on the synthesis and turnover of microvillous membrane glycoproteins in suckling rat intestine. Synthesis and degradation of intestinal mucosal and microvillous membrane glycoproteins were studied in control suckling rats, and suckling rats given cortisol acetate by intraperitoneal injection for 3 days. Cortisol acetate had no effect on total uptake of radioactive glucosamine by the protein free compartment of rat intestine. Early incorporation of [1(-14)C]glucosamine by intestinal glycoproteins was enhanced by cortisol, but stimulation was the same in membrane and homogenate fractions. Polyacrylamide gel electrophoresis of membrane proteins solubilized with 2% sodium dodecyl sulphate demonstrated a cortisol dependent change, characterized by loss of faster travelling glycoproteins, and a corresponding shift in maximum labelling at 3 h from these glycoproteins to more slowly migrating glycoproteins. Degradation was studied qualitatively with a double isotope technique. Glycoprotein degradative rates appeared to be stimulated by cortisol, but similarly in membrane and total homogenate fractions. On polyacrylamide gels, the areas occupied by glycoproteins with the highest apparent degradative rates, corresponded closely with the areas of most active labelling at 3 h. The rate of degradation in the most actively labelled zone appeared to be higher after cortisol than in the controls. The results indicate that cortisol does not alter membrane composition by inhibiting degradation of selected glycoproteins, and are consistent with a model in which cortisol stimulates the synthesis of specific membrane glycoproteins in suckling rats, while inhibiting synthesis of other glycoproteins.


Localization of oxalacetate keto-enol-tautomerase. The intracellular location of oxalacetate keto-enol-tautomerase (oxaloacetate keto-enolisomerase) (EC 5.3.2.2) has been determined in two types of animal cells, rat liver and pig kidney. Two fractionation procedures were adopted and modified to suit each type of tissue. One fractionation procedure gave the soluble phase, microsomal and mitochondrial fractions, while the other isolated the nuclear fraction. The tautomerase is distributed among the soluble phase, microsomes and mitochondria in both tissues. Fractionation efficiency was checked by determining percentage recoveries of enzymic activity and total protein after each step, by microscopy studies and by determining the distribution of several marker enzymes.


Wheat embryo ribonucleates. VI. Comparison of the 3'-hydroxyl termini in 'rapidly labelled' RNA from metabolizing wheat embryos with the corresponding termini in ribosomal RNA from differentiating embryos of wheat, barley, corn and pea. The NaCl-insoluble (2.5 M, 0 degrees C) fraction of wheat embryo RNA (iRNA) can be labelled when wheat embryos are subjected to either short-term (0.5 h) or long-term (24 h) imbibition in a medium that contains tritium-labelled adenosine, guanosine, cytidine and uridine. Electrophoretic analyses reveal that, after short-term labelling, there is a broadly heterodisperse distribution of radioactivity in 'rapidly labelled' i[3H]RNA, but after long-term labelling, there is an essentially trimodal distribution of radioactivity in i[3H]RNA. End-group analyses reveal that, after short-term labelling, adenosine is the principal 3'-hydroxyl terminus in all centrifugal subfractions of 'rapidly labelled' i[3H]RNA, whereas cytidine (in 5.8S rRNA), guanosine (in 18S rRNA) and uridine (in 26S rRNA) are the principal 3'-hydroxyl termini in centrifugal subfractions of wheat embryo i[3H]RNA. Guanosine is also the principal 3'-hydroxyl terminus in the 18S rRNA of differentiating embryos excized from both monocotyledonous (wheat, barley, corn) and dicotyledonous (pea) seedlings. The implications that the end-group measurements may have for current views about the possible biochemical involvements of 3'-hydroxyl terminal sequences in both mRNA and 18SrRNA are subjects of discussion. Incidental to the principal investigation, an existing technique for analyzing the RNA contents of cellular materials has been appropriately modified to circumvent interference from uv-absorbing pigments, which, when present, prevent application of the method to plant materials.


Effects of diet on catabolism and excretion of (26-14C)cholesterol in rats. The catabolism and excretion of [26-14C]cholesterol was studied in rats on semisynthetic and commercial diets low in fat or containing 15% butter or corn oil. Rats on the low fat commercial diet oxidized the labeled cholesterol to 14CO2 at more than twice the rate of those on the semisynthetic diet. Fecal excretion of labeled lipid was also somewhat higher with the commercial diet. The added fats had little effect on rate of oxidation of cholesterol but dietary corn oil stimulated fecal excretion of labeled lipid. The rate of loss of labeled cholesterol through oxidation and excretion showed a positive correlation with cholesterol biosynthesis, as measured previously by acetate incorporation into cholesterol in rats on the same kinds of diet. A simple method for efficient trapping and counting of 14CO2 was developed, which facilitated measurement of low levels of 14CO2 in expired air. Estimation of bile acid production from the rate of oxidation of [26-14C]cholesterol to expired 14CO2 and the specific activity of plasma cholesterol gave somewhat higher values than those obtained by other methods. Possible reasons for this difference are discussed.


Persistent effects of ouabain treatment on human lymphocytes: synthesis of DNA, RNA and protein in stimulated and unstimulated cells. Pretreatment of human lymphocytes for 2 days in 2 X 10(-6)M ouabain caused irreversible loss of their subsequent capacity to stimulate in the mixed lymphocyte reaction (MLR). Pretreatment for the same period with 10(-7)M ouabain resulted in an enhanced incorporation of thymidine into DNA of the responding cells in the MLR; this effect was also on the stimulating cells, as previously reported by Christen et al. (Cell, Immunol. 19, 137-142 (1975)). Pretreatment of stimulating lymphocytes with 10(-7)M ouabain caused a persistent but reversible inhibition of the synthesis of RNA and protein in the MLR; peak incorporation of labelled uridine or alanine reached the same level as that of the control cultures, but 24 h later. Exactly the same persistent but reversible inhibition was found in the case of DNA syntheis of cells pretreated with 10(-7)M ouabain and then stimulated by antigens (streptolysin-O and varidase) or by mitogens (phytohemagglutinin and concanavalin A); the same level of incorporation of labelled thymidine occurred but 24-48 h later than in the case of the controls. Pretreatment with the cardiotonic steroid under these conditions also resulted in a pronounced inhibition of the basal, unstimulated levels of RNA and protein synthesis in the case of both control lymphocytes and those which had been treated with mitomycin C. The effects of ouabain pretreatment on basal RNA and protein synthesis were identical for both 2 X 10(-6)M and for 10(-7)M; the effect of pretreatment of stimulating cells with these two concentrations was completely opposite: irreversible inhibition of the proliferative response of allogeneic responding cells at the former concentration and delayed activation at the latter.


The development of dermal lesions and alopecia in male rats fed rapeseed oil. For 8 weeks 10 male weanling Sprague-Dawley rats were fed a semisynthetic diet containing by weight either 20% corn oil or rapeseed oils containing different amounts of erucic acid (Brassica napus var. Zephyr, 0.6%; B. napus var. Oro, 1.8%; B. campestris var. Span, 4.8%; or B. campestris var. Echo and Arlo, i.e., regular rapeseed oil, 23.6%). At 4-5 weeks after the experiment began, rats receiving the diets containing rapeseed oil showed evidence of alopecia and developed scaly, hemorrhagic, and necrotic tails, as well as scaliness of the feet, similar to the lesions described in essential fatty acid (EFA) deficiency. This condition became most severe between 5 and 8 weeks and had disappeared by 14 weeks. Fatty acid analysis of the diets and tissues of the animals did not reveal any evidence of EFA deficiency. It is suggested that these symptoms observed might be related to a possible inhibition of prostaglandin biosynthesis in rats fed rapeseed oils.


Storage and release of labelled acetylcholine in the myenteric plexus of the guinea-pig ileum. Guinea-pig ileum myenteric plexus-longitudinal muscle preparation was superfused with [3H]choline for 15 min either without being stimulated or during field stimulation at 0.1 or 16 Hz; the preparation was then either removed immediately or after 75- or 135-min superfusion with hemicholinium-3 (HC-3) and the total acetylcholine (ACh) and [3H]ACh contents were determined. For measuring the release of [3H]ACh the preparation was stimulated for 60 min the second time at 0.1 or 16 HZ in the presence of hemicholinium. Exposure to [3H]choline without stimulation resulted in the formation of [3H]ACh stores which were maintained in the first 75 min but decreased therafter. Labelling during stimulation at 16 Hz produced the largest and best maintained [3H]ACh content. Following labelling during 0.1-Hz stimulation, more label could be released than following labelling in the absence of stimulation. Labelling during 16-Hz stimulation did not increase any further in fool of [3H]ACh accessible to release by 0.1-Hz stimulation, but caused a 2.5 times increase in the pool from which Hz stimulation released [3H]ACh. These results suggest that two populations of cholinergic neurons exist in the myenteric plexus, one activated only by high frequency stimulation, the other by both high and low frequency stimulation.


Asialoglycoprotein clearance in the chicken: evidence for the lack of a hepatic asialoglycoprotein receptor. The behaviour of desialylated human and chicken acid alpha1-glycoproteins is reported in chickens. Although desialylation resulted in accelerated disappearance rates from the plasma of both proteins, nevertheless the asialoproteins were eliminated much more slowly than expected on the basis of earlier observations in mammals. Analysis of tissue radioactivities, including kidney, liver, lung and spleen, failed to demonstrate any accumulation of the labeled asialoproteins in the liver, which is contrary to the situation in mammals. The main pathway for the elimination of desialylated human acid alpha1-glycoprotein in the chicken is via the kidney (tubular catabolism and/or urinary excretion). The clearance of desialylated chicken acid alpha1-glycoprotein is more complex as it involves the kidney as well as the reticuloendothelial system. These findings indicate that, unlike mammals, chickens do not possess a hepatic plasma membrane receptor for asialoglycoproteins. This raises the possibility that the presence or absence of this specific receptor may constitute a fundamental biological difference between mammals and birds.


Effects of a series of alcohols on the binding of a fluorescent dye to erythrocyte membranes. 1. The effects of a series of aliphatic alcohols (methanol to octanol) on membrane proteins of erythrocytes were studied by monitoring the flueorescence of a dye (1-anilino-8-naphthalenesulfonic acid (ANS)) that adsorbs to erythrocyte ghost membranes. Low concentrations of all the alcohols reduced the ANS fluorescence of the membrane-ANS suspensions; lent to those which protect against hypotonic hemolysis on intact erythrocytes; higher concentrations markedly increased the fluorescence. Ethanol and methanol decreased ANS fluorescence at all concentrations. 2. Lytic concentrations of saponin did not increase ANS fluorescence and did not modify the membrane action of the alcohols. 3. None of these effects were observed in liposomes prepared from lipid extracts of the erythrocyte membrane. 4. Since the apparent dissociation constant for the ANS-membrane interaction was unchanged in the presence of the alcohols, it was assumed that the fluorescence changes anesthetic concentration of the alcohols alter the conformation of membrane proteins, as indicated by the decreased number of ANS binding sites.


Propranolol antagonism to the effect of furosemide on the compostion of endolymph in guinea pigs. Furosemide, administered intravenously (50 mg/kg) to guinea pigs, caused an increase in the sodium concentration and a decrease in the potassium concentration of endolymph, and a fall in the endolymphatic potential. The furosemide-induced electrolyte changes were prevented by pretreatment of five guinea pigs with propranolol given intravenously (2 mg/kg). The fall in the endolymphatic potential was not prevented by propranolol. Local administration of furosemide to the perilymphatic or endolymphatic space caused a fall in the endolymphatic potential, but had no effect upon the concentrations os sodium and potassium of endolymph. These studies  provide additional information suggesting the mutual independence of the endolymphatic potential and sodium and potassium concentration gradients.


Effects on tissue and electrolytes of a mineralocorticoid blocker during DOCA-induced potassium depletion. Chronic experiments were carried out on three groups of rats to evaluate tissue and electrolyte effects of a mineralocorticoid blocker canrenoate potassium (SC-14266) during DOCA-induced hypokalemic metabolic alkalosis. Group I animals received DOCA alone, group II received DOCA plus canrenoate, while group III received canrenoate alone. The daily dose ratio (per kilogram of body weight) was 180 mg canrenoate-0.45 mg DOCA. All animals ate a synthetic diet and drank 0.15 N NaHCO3. Group II animals demonstrated a lesser degree of metabolic alkalosis and a higher muscle potassium content when compared with group I rats. The most conspicuous histological abnormality was myocardial necrosis, the degree and extent of which was impressively reduced by the blocking agent.


Descending influences of periaqueductal gray matter and somatosensory cerebral cortex on neurones in trigeminal brain stem nuclei. Single relay (to thalamus) and nonrelay neurones that responded to innocuous and/or noxious oral-facial stimuli were located in trigeminal brain stem nuclei oralis and caudalis. The responses of the cells and the digastric muscle to these stimuli were tested with conditioning stimulation of the periaqueductal gray matter (PGM) and somatosensory cerebral cortex in cats. A greater suppression of nociceptive responses with PGM stimulation was noted, and this effect may contribute to the profound analgesic action that has been reported to occur with PGM stimulation.


The interaction of glutamic and aspartic acids with excitatory amino acid receptors in the mammalian central nervous system. Firing rates of single thalamic neurones of the cat and the rat have been measured as functions of the currents used to apply glutamic and aspartic acids electrophoretically. Hill plots of the data suggest that three amino acid molecules are probably required to activate an excitatory receptor.


Intracellular Mg2+ increases neuronal excitability. Injection of Mg2+ into spinal motoneurons of cats leads to a depolarization, associated with a fall in membrane conductance, diminution in post-spike hyperpolarization, and increased excitability. This action has an apparent reversal level substantially more negative than the resting potential, and can be ascribed to a fall in K+ membrane conductance. Since these effects are opposite to those produced by intracellular Ca2+, it is suggested that Mg2+ probably competes with Ca2+ at the Ca2+-activated K+ ionophoreal free ionophores. Neuronal excitability can be regulated by the ratio of internal free Ca2+/Mg2+.


DNA relatedness among species of Enterobacter and Serratia. Species of Enterobacter and Serratia were examined for deoxyribonucleic acid relatedness to Klebsielleae, to atypical erwiniae, and to other members of Enterobacteriaceae. Deoxyribonucleic acid hybridization and then hydroxyapatite chromatography was the technique used to assess relatedness. Strains of Enterobacter cloacae formed two separate hybridization groups that correlate with the presence or absence of yellow pigment. Pigmented E. cloacae were 75-100% related, but they were only 40-50% related to unpigmented strains. Conversely, unpigmented strains were 70% or more related but were only 40-50% related to the pigmented strains. Both pigmented and unpigmented E. cloacae were 40-45% related to Enterobacter aerogenes and klebsiellae, and 20-30% related to Serratia species and Enterobacter hafniae. Atypical erwiniae were highly related to E. cloacae. Serratia marcescens strains formed one closely related group. Serratia liquefaciens strains formed a single, more disperse, relatedness group, as did isolates of Serratia rubidaea. These species were related throughout a substantial portion of their genomes. A group of lysine-positive "Citrobacter-like" strains were 40-50% related to Serratia species. Only four E. hafniae strains were tested. Two of these were highly related, while the other two were only 50% related to the reference strain. Enterobacter hafniae was only 15-20% related to other Enterobacteriaceae.


Morphological, physiological, and biochemical characteristics of some violet-pigmented bacteria isolated from seawater. Sixteen violet-pigmented heterotrophic bacilli were isolated from Mediterranean coastal waters. Morphological and physiological studies showed that they have a number of characteristics specific to the genus Chromobacterium. However, the absence of catalase, the presence of oxidase, and, more especially, the low percentage of bases guanine and cytosine in their DNA exclude them from the genus. The specificity of some characters assigned to Chromobacterium can thus be discussed. Several features allow us to consider such bacteria as being related to the genus Alteromonas; their consistency within the 16 strains investigated leads us to consider them as a single species, for which the specific name Alteromonas luteo-violaceus (sp. nov.) is proposed.


Glycerol metabolism in Rhizobium.

Glycerol metabolism in Rhizobium. Four strains of Rhizobium japonicum and one strain of R. trifolii were grown on glycerol and found to contain a soluble ATP-glycerol kinase and a particulate glycerolphosphate dehydrogenase. Both enzymes are induced by glycerol. The presence of NAD+-or NADP+-glycerol dehydrogenase was not detected in any of the strains. No significant differences were found in the glycerol metabolic pathway between fast-and slow-growing rhizobia.


Temporal origin of viral phospholipids of the enveloped bacteriophage phi 6. The enveloped bacteriophage phi 6 contains a higher relative level of the negatively charged phospholipid phosphatidylglycerol than is found in the membranes of the host bacterium. During infection of Pseudomonas phaseolicola with phi 6, the level of phosphatidylglycerol synthesis increases significantly. The lipid used to form the viral envelope consists almost entirely of cellular phospholipids synthesized before infection and phosphatidylglycerol synthesized after infection. Based on these and previously published results, a speculative model for this viral envelope formation process is presented.


The nuclear DNA-dependent ribonucleic acid polymerases of the dermatophytic fungus Microsporum gypseum. The DNA-dependent RNA polymerases of the dermatophytic fungus Microsporum gypseum were partially characterized. Nuclear extracts prepared from vegetative mycelia were fractionated by DEAE-Sephadex chromatography into three enzyme species which resembled in most of their characteristics those of other eukaryotic organisms.


Enterotoxin B formation by fermentation mutants of Staphylococcus aureus. An appreciable fraction of carbohydrate-negative (car) mutants of Staphylococcus aureus strains ATCC 14458, 778, and S-6 exhibit increased enterotoxin B (SEB) production. In addition, some lac and mtl mutants of these strains also display enhanced SEB formation. All such mutants appear to be point mutations. Mutagen-induced reversions of high SEB producing car, mtl, or lac mutants yield varying amounts of SEB and some clones seem to be restored to the characteristics of the parent type. A few sequentially isolated lac, mtl double mutants of strain 778 elaborate much more or much less SEB than either the lac or the mtl single mutants.


Studies of the cellular and free lipopolysaccharides form Neisseria canis and N. subflava. Cellular and free lipopolysaccharides (LPS) obtained from Neisseria canis and N. subflava were essentially identical. Both cellular and free lipopolysaccharides contained O-polysaccharides of the following composition: L-rhamnose (46 mol), D-glucose (16 mol), L-glycero-D-manno-heptose (2 mol), ethanolamine (2 mol), 3-deoxy-D-manno-octulosonic acid (1 mol), and phosphate (1.5 mol). The core oligosaccharide, which was common to the cellular and free LPS of both organisms, contained L-rhamnose (4 mol), D-glucose (2 mol), L-glycero-D-manno-heptose (2 mol), 3-deoxy-D-manno-octulosonic acid (1 mol), ethanolamine (2 mol), and phosphate (1.5 mol). Accumulated results on LPS composition and structure indicated that Neisseria perflava, N. subflava, and N. flava could not be combined into a single species. On the basis of its nutritional requirements and LPS structure, N. canis could be considered a strain of N. subflava.


Morphology and host range of virulent phages of lotus rhizobia. Nineteen virulent bacteriophages for fast- and slow-growing rhizobia were isolated. Most of the phage isolates were of two morphological types, and these showed specificity for either the fast- or the slow-growing rhizobia. The ecological distribution, morphology, and host range of the phages is presented. Classification of lotus rhizobia is discussed on the basis of phage typing.


The accumulation of succinate by the yeast Brettanomyces bruxellensis. The metabolism of Brettanomyces bruxellensis was investigated to determine the metabolic block responsible for the accumulation of acetate seen in cultures of this yeast. In glucose-grown cultures the major non-volatile intracellular organic acide was succinic acid. These cultures also had low levels of succinic dehydrogenase (succinate dehydrogenase, EC 1.3.99.1) and did not produce CO2 from the carbons of ethanol. It was concluded that a block in the oxidation of ethanol occurred at the level of succinic dehydrogenase. If glucose-grown cultures were transferred to ethanol medium, the block in the metabolism of ethanol was partially overcome; the level of succinic dehydrogenase increased, the concentration of the intracellular succinate decreased, and CO2 could be produced from C-1 of ethanol.


Microbial utilization of raw and hydrogenated shale oils. The biodegradability of raw and hydrogenated shale oils prepared by a retort process were studied under psychrophilic and mesophilic conditions. Changes in bacterial numbers and the chemical composition of the oils were monitored using a plate count and chromatographic techniques respectively. Raw shale oil was found to be relatively resistant to microbial attack whereas hydrogenated shale oil was readily utilized for microbial growth. Populations enriched on raw shale oil had a reduced ability to use hydrogenated shale oil under similar conditions. Gram-negative rods predominated in all enrichment populations. It is recommended that to facilitate clean up of shale oil spills, raw shale oil be reduced at the extraction site before transport.


Morphological modifications of cells of Clostridium pasteurianum caused by growth on sulfite. The morphology of Clostridium pasteurianum cells grown on 10(-2) M SO32- showed significant alteration in cell shape and the absence of the electron translucent reserve polysaccharide (amylopectin) when compared to sulfate-grown cells. At the lower sulfite concentrations (10(-3) and 10(-4)M SO32-) the cells showed the cytoplasmic changes noted above but the cell shapes were not modified.


Degradation of homogentisate by strains of Bacillus and Moraxella. The metabolic pathways whereby strains of Moraxella and Bacillus degrade homogentisate (2,5-dihydroxyphenylacetate) are delineated. The Moraxella (strain OA3) is shown to degrade homogentisate via the pathway previously described in liver: homogentisate is cleaved by a 1,2-dioxygenase (E.C 1.13.11.5) yielding maleylacetoacetate which is isomerized by a GSH-dependent isomerase to fumarylacetoacetate before hydrolysis to acetoacetate and fumarate. A strain of Bacillus (B11c) is shown to catabolize homogentisate via a previously undescribed version of the above sequence: homogentisate is cleaved by a 1,2-dioxygenase (E.C 1.13.11.5) yielding maleylacetoacetate which is hydrolyzed directly to acetoacetate and maleate.


Toxigenic species of Penicillium, Fusarium, and Aspergillus from weevil-damaged pecans. Of a total of 2392 fungi isolated from weevil-damaged pecans, 46.4% were Alternaria and Epicoccum, 23.9% were Penicillium, 12.4% were Pestalotia and Monochaeta, 6.5% were Cladosporium, 6.4% were Fusarium, and less than 2% each were Phoma, Aspergillus, Rhizopus, Trichothecium, and miscellaneous. Chloroform extracts of 34 of 105 representative Penicillium isolates, 3 of 28 Fusarium isolates, and 3 of 23 Aspergillus isolates were toxic to day-old cockerels during three bioassays. Eight of the toxic extracts from Penicillium spp. were tremorgenic. One tremorgenic isolate was identified as P. paxilli, four were identified as P. lanoso-coeruleum, and three as P. cyclopium. Nine of the non-tremorgenic isolates were identified as P. citrinum, five as P. aurantio-virens, three as P. oxalicum, and two as P. meleagrinum. Others were identified as one each of P. brevi-compactum (Series), P. nigricans (Series), P. roqueforti, P. rugulosum (Series), P. terrestre, and P. stoloniferium. One was unidentified. Toxigenic Aspergillus isolates were all A. flavus. Two of the toxic Fusarium isolates were F. moniliforme, and one was unidentified.


Resistance of Thiobacillus novellus to mitomycin C and rifampicin. Thiobacillus novellus is highly resistant to mitomycin C and rifampicin. This resistance is not due to insusceptibility of the target molecules to the drugs, since mitomycin C cross-links the DNA and rifampicin inhibits the DNA-dependent RNA polymerase of T. novellus in vitro.


Comparison of the cell envelope proteins of Micrococcus cryophilus with those of Neisseria dnd Branhamella species. In an attempt to elucidate the relation between Micrococcus cryophilus, Neisseria caviae, Neisseria ovis, and Branhamella catarrhalis, fractions derived from outer membranes of a strain of each organism were examined for protein composition by SDS - polyacrylamide gel electrophoresis. Micrococcus cryophilus outer membrane protein showed extensive similarities to that of N. ovis and contained a heat-modifiable protein which behaved almost identically with the corresponding bands previously shown to exist in N. caviae and N. ovis. Branhamella catarrhalis protein was distinctly different from those of M. cryophilus and the two 'false neisserias' N. caviae and N. ovis.


beta-Xylosidases in the yeast Cryptococcus albidus var. aerius. beta-xylosidase activity has been detected in cell-free extracts and in culture fluids when Cryptococcus albidus var. aerius was grown on glucose as the sole carbon source. The enzyme appears to be constitutive. Mild acid treatment of whole cells suggested that the total activity is located in the periplasmic space and some experiments indicated that it is partially associated with the cell walls. DEAE-Sephadex A50 chromatography has shown that there are two different forms of beta-xylosidase in the cell-free extracts, but only one form is present in the supernatants of culture.


The isolation of Vibrio parahaemolyticus and related vibrios from moribund aquarium lobsters. Vibrios were isolated in pure culture from the hemolymph of 7 out of 28 dead or dying aquarium lobsters which had been acclimated to 20-22 degrees C. One isolate was identified as Vibrio parahaemolyticus, one as a related marine Vibrio (probably V. marinus), and five as Vibrio alginolyticus. No isolates of halophilic Vibrio species were made from healthy lobsters using thiosulfate citrate bile salts sucrose agar (TCBS).


Temperature optima for bacteria and yeasts from cold-mountain habitats. Optimal temperatures for the growth of bacteria and yeasts isolated from several cold-mountain habitats were determined. The lowest optimal temperatures encountered were in the 10-15 degrees C range, even though most of the isolates were obtained from sites at or near 0 degrees C.