Survey on AIDS, fear and infection control: attitudes affecting management decisions. As a result of increased public concern about AIDS and dental treatment, dental professionals need to cope with legislative reactions, increased infection control costs, patient anxiety and vigilance on the part of law enforcement agencies regarding compliance with "universal precautions." Recommendations abound for educating patients about dental office infection control to allay irrational fears and market dental office asepsis, but few studies quantitatively measure these needs or address the behavioral concerns patients have about AIDS infection related to dental care. In this investigation, dental patients were surveyed to determine their beliefs, attitudes and behaviors regarding AIDS and dental office infection control. Several important educational caveats were identified. This paper considers these challenges and provides patient education and practice management recommendations consistent with a preventive focus on allaying dental patients' fears while building more successful dental practices.


Effect of pretreatments (imprinting) with different concentrations of insulin on insulin binding of nuclear envelope and plasma membrane in Tetrahymena. About 4 h following treatment with 10(-6) - 10(-10) M insulin (imprinting) there was a down-regulation both in the plasma membrane and in the nuclear envelope of Tetrahymena, i.e. there was a decrease in the binding value related to the control. In each concentration tested the imprinting resulted in increased FITC-insulin binding after 24 and 48 h of treatment; the imprinting was independent of the concentrations. In the case of the plasma membrane the power of binding was directly proportional to the increase of the hormone concentration participating in the imprinting. For the nuclear envelope the optimal concentration was 10(-8) M. At very low concentrations (10(-10) M) the binding resulting in imprinting was insignificant in the plasma membrane but it was still present in the nucleus.


Changes in proteolytic susceptibility of human erythrocyte membrane proteins during red blood cell aging. The method employed facilitated analysis of the digestion of denatured proteins, depleted in their natural membrane environment. The susceptibility of human erythrocyte membrane proteins to digestion with trypsin was studied by the two-dimensional electrophoretic method. Ghosts were isolated from erythrocytes fractionated according to density (age). Spectrin and band 3 protein from membranes isolated from the youngest cells were significantly more slowly degraded than proteins from middle-age cell membranes and from the oldest cells.


[Monitoring of maternal-fetal hepatitis B virus transmission by molecular hybridization technique]. Maternal venous blood (MB), umbilical blood (UB) and placental tissue (PT) were collected from 40 HBsAg positive mothers and their neonates, and also blood from 17 babies aged 3-6 months old of this group (BB). All samples were determined for hepatitis B virus (HBV) DNA by molecular hybridization technique using Bio-HBV DNA probe. The results showed: HBV DNA positive rate of MB was 35.0%, 47.5% for UB, 75.0% for PT and 29.4% for BB. 32 P-HBV DNA probe was also used to examine MB and PT. The positive rates of HBV DNA were 30.0% and 70.0% respectively. There was no significant difference between the results of the 2 probes. We considered: (1) With the rapid development of HBV detection technique, the detectable rate of intrauterine infection increases accordingly. (2) Besides transplacental infection, other transmission routes might be existed. (3) The detection of HBV DNA in UB, PT and in the blood of babies born by HBV DNA positive mother within 6 months old provides the reliable diagnosis. (4) HBV DNA molecular hybridization is an accurate and sensitive method for the diagnosis of HBV intrauterine infection.


[Hemodynamic effects of antihypertensive drugs on pregnancy-induced hypertension]. Aiming to select a proper kind of antihypertensive drug for mild and moderate pregnancy-induced hypertension (PIH), 30 patients with PIH were examined by using noninvasive cardiovascular detector TP-CBS. The basic hemodynamic parameters included mean artery pressure (MAP) Kpa, heart rate (HR) bpm, cardiac index (CI) L min-1/m2 and total peripheral resistance (TPR) PRU. The 30 cases were divided into 6 groups with 5 each to take a single dose of prazoxin, phentolamine, methyldopa, captopril, nifedipine and aminophylline respectively. Hemodynamic parameters were examined consecutively every 30 minutes for 4 hours after ingesting the above drugs. The results showed that all the 6 medicines had effects of lowering MAP and TPR without change of cardiac output. Nevertheless, viewing from the effect of lowering blood pressure, change of pulse rate, time of action and incidence of side effects, we considered that nifedipine is superior to the other 5 and can be preferably recommended at outpatient clinic.


[Analysis of 930 cases of low birth weight newborns]. The birth weight of 13,048 newborns were analyzed. The results showed: (1) The incidences of low birth weight (LBW) and very low birth weight (VLBW) were 60.10% and 11.19% respectively. (2) The perinatal mortality rates (PMR) for birth weight of < 1,500 g, 1,500-2,499 g and > or = 2,500 g were 465.8%, 127.60% and 5.30% respectively, (3) The causes of perinatal death included hypoxia, deformities, neonatal diseases and therapeutic induction of labour (38.80%, 25.86%, 22.84% and 12.50% respectively). The incidence of malformation in < 2,500 g group was 36 times of that in > or = 2,500 g group. (4) The incidence of LBW was significantly related to gestational age (P < 0.01). (5) The incidences of LBW among groups of various maternal age were significantly different, and the best age for childbirth was 25-29. (6) LBW was associated with mother's occupation, and LBW newborns from woman farmers were 5.8 times of those from intellectuals. (7) The PMRs differed significantly among groups of different maternal cultural background (P < 0.01).


[Improving the curative effect of chemotherapy on gynecological malignant tumor by catheterization of internal iliac artery]. Seventeen cases of gynecological malignant tumor received 27 infusion chemotherapy by selective catheterization via internal iliac artery. Among them, 14 cases (82.4%) were cancer of advanced stage. All of the cases were followed up. 77.8% of cases showed short-term good response. The intermittent mean duration without tumor growth was 12.5 months. The determination of platinum confirmed that the vascular embolism chemotherapy of tumor is one of the best approaches for pelvic tumors.


[Assay of urine cysteine proteinase in diagnosing gynecological malignant tumors]. Cysteine proteinases (CP) belong to the subclass of endopeptidase, and have been considered to play an important role in spreading cancer cells. Cysteine proteinases in urine (UCP) were determined in 71 healthy women, 76 patients with gynecological benign tumors and 125 cases (173 samples) with gynecological malignant tumors. Enzyme levels were assayed using the artificial substrate CSZ-Ala-Arg-AFC by detecting the release of free AFC with the aid of a fluorometer. The value ranged from upper 80% to 99% of UCP in 71 normal women and was calculated with the percentile method. The results showed that ROC curve displayed a highly sensitive character. The sensitivity and specificity for gynecological malignant tumor were 91.8%, and 71.7% respectively. The sensitivities of UCP for ovarian cancer, cervical cancer, carcinoma of endometrium and cancer of vulva were 96%, 91%, 85.7% and 72.7% respectively. Due to its high sensitivity. It was suggested that UCP assay can be a good screening test to distinguish gynecological malignancy from benign tumors. The accuracy of diagnosing gynecological malignancy may be improved if UCP assay is combined with other tests with higher specificity.


[A comparative morphometric and DNA content study of endometrial hyperplasia and adenocarcinoma]. The DNA content and morphometric study of four groups of endometrial proliferations were compared: adenomatous hyperplasia (21 cases), atypical hyperplasia (13 cases), adenocarcinomas with superficially myometrial invasion (9 cases) and with deep myometrial invasion (8 cases). The normal DNA histogram patterns were identified in the majority of the adenomatous hyperplasia. The important difference between proliferative and neoplastic endometrium was the size and shape of nuclei of epithelial cells. The DNA content and morphometric measurement of atypical hyperplasia and well-differentiated adenocarcinomas were similar. The highest proportions of cells with polyploidy were found in the deep invasive carcinomas. The study suggests the DNA content determination and morphometry are useful supplementary methods for observing the continuous pathologic process.


[Use-effectiveness of natural family planning by ovulation method]. Cervical mucus (CM) peak and plasma LH surge were examined in 19 women. The consistency of the CM peak and ovulation after the plasma LH surge demonstrated that as an indicator of natural family planning (NFP), the CM can scientifically predict the occurrence of ovulation. Based on these results, 300 healthy women were recruited into this study by self examination of CM. A total of 3,393 cycles was observed. There were 29 pregnancies reported, and the continuation rate was 90.3/100 women year. It showed that the NFP is an acceptable, safe and effective birth control method for Chinese women.


[A multi-center double blind prospective study of ridaura in the treatment of rheumatoid arthritis]. 223 cases of definite rheumatoid arthritis were studied which were divided into ridaura treatment group and placebo group. Observations were made double-blind and prospectively. Judging from the comparison of therapeutic results of each treatment group on each clinical and laboratory parameters and of effective rate of each treatment group on the parameters and by comparing the physicians' and patients' assessments to the ridaura or placebo treatment, it was evident that the ridaura was much superior than placebo, possessing statistical significance. In physicians' assessment 14.2% failed to improve in the ridaura group but being 52% in the placebo group. Ridaura was a slow-acting drug, the earliest time for it to show clinical improvements being 2-4 months after medication. Adverse effects of ridaura were limited; incidence of loose bowel movements was much lower than that reported in the western countries. Among the 148 cases of the ridaura group, only two cases failed to complete the six months treatment course because of untoward reactions.


[Role of enteric Klebsiella pneumonia infection and HLA-B27 in ankylosing spondylitis]. Klebsiella pneumonia (KP) infection and HLA-B 27 have been shown to be strongly associated with ankylosing spondylitis (AS). In the present study, faecal cultures were performed and showed faecal carriage rate of KP was much higher in patients with AS (10/30) and hospital volunteers (2/10) than in the non-hospital volunteers (0/20). An octadecapeptide encompassing the shared hexamer between HLA-B 27 and KP nitrogenase residue was synthesized and autoantibodies against this short peptide were detected in sera of patients with AS and Reiter's syndrome (RS) and other related disease and normal controls. The results showed that such autoantibodies were detected in 42.2% of AS and 30% of RS patients yielding positive rate much higher than those found in other control groups. It is concluded that enteric KP infection were strongly implicated in the pathogenesis of AS probably by the mechanism of molecular mimicry with HLA-B 27.


[Endoscopic balloon dilatation for achalasia: an effect observation in 38 cases]. From February 1988 to November 1990, thirty eight patients with achalasia were treated endoscopically with micro-vasive regiflex dilator (MRBD). Immediate success rate was 100% and the long-term effect 89.4%. No serious complications such as perforation of bleeding occurred. MRBD is superior to conventional dilators in treating this disease and probably the method of first choice.


[Value and mechanism of abnormal postexercise systolic blood pressure response for detection of coronary artery disease]. The value of an abnormal ratio of recovery systolic blood pressure to peak exercise SBP for detecting coronary artery diseases (CAD) is controversial. We evaluated the ratio in 39 patients with angiographically documented CAD and 52 patients with normal coronary artery undergoing treadmill exercise. If a response with the ratio higher than 1.0 and 0.8 at 1 and 3 min. of recovery was considered as abnormal, the sensitivity for detecting CAD was 66.7%, the specificity 73.1% and the accuracy 70.3%. If ST segment depression is combined into the criteria, the specificity and accuracy reach 94.2% and 76.9%. In CAD, the ratio at 3 min. of recovery showed significant negative correlation with resting left ventricular ejection fraction (LVEF) (r = -0.461, P < 0.01). It is suggested that low resting LVEF may be one of the mechanism of this abnormal ratio in CAD.


[Bone histology and clinical diagnostic criteria in aluminum-induced bone disease]. Bone remodeling and aluminum (Al) staining were carried out in 429 bone biopsies from patients with uremic bone disease, 273 cases were Al positive (64%). In high-turnover, low-turnover and mixed type of renal osteodystrophy the Al-positive rate was 29%, 75% and 80%, and Al deposition on bone surfaces was 44 +/- 33%, 80 +/- 30% and 62 +/- 35% respectively. Thus the low-turnover and mixed type have a higher Al-positive rate and more Al deposition than the high-turnover type. Animal experiments using decalcified bone matrix implants showed that Al inhibited all bone remodeling processes except cartilage formation. These and other data indicate that Al induces low-turnover bone disease, i.e., osteomalacia or aplastic bone disease. Osteomalacia in our series showed increased osteoid area and mineralization lag time, and decreased calcified bone area, bone mineralization rate and cells number. Aplastic bone disease was similar with that but had reduced osteoid and a normal ratio of steroid to calcified bone. The relationship of these studies to clinical diagnostic criteria of Al-induced bone disease is discussed.


[External pituitary irradiation therapy for acromegaly]. 128 acromegaly patients were followed up for 1-23 years (mean 5.9 +/- 5.0 years) after external pituitary irradiation; among them 104 patients received fractional irradiation with an ultimate total dose of 4000-5000 rad. The remaining patients received a total dose of either < 4000 rad or > 5000 rad. Human growth hormone (hGH) level was measured after an oral load of 100g glucose to evaluate the effect of irradiation. After external pituitary irradiation, the serum level of hGH decreased progressively. The decrease was more rapid in the first three years with a decrement of 35.1% per year. 36.2% of all the patients has been judged as clinically inactive with low serum hGH level of < or = 5 ng/ml. 62.1% of the patients was considered as slightly active with hGH level < or = 10 ng/ml in the 15th year after therapy. The effect of irradiation was not influenced by the age of the patients, the course of acromegaly, the size of sella turcica and operation prior to irradiation. If the total dose of irradiation is lower than 4000 rad, the effect will not be good.


[Monitoring of gentamicin blood level].

[Monitoring of gentamicin blood level]. A prospective randomized comparison of blood concentration as well as manifestations of ototoxicity and nephrotoxicity in groups with conventional and individualized administration of gentamicin was carried out in a total of 106 hospitalized patients. Therapeutic serum concentrations (peak 4-9 mg/L, though less than 1 mg/L) were achieved in 50% of the patients of conventional group and in all the patients of individualized group. Incidence of auditory and renal toxic reactions was high in the conventional group, being 27% and 30% respectively, while in the individualized group, the corresponding figures were 2.8% and 0%. Therefore, individualized administration of gentamicin based on data from therapeutic drug monitoring can markedly decrease the toxic effect and increase the therapeutic efficacy. It is worthwhile to use this kind of administration clinically.


[Pulmonary angitis and granulomatosis].

[Pulmonary angitis and granulomatosis]. 16 patients of Wegener's granulomatosis, 4 of allergic angiitis and granulomatosis, 3 of lymphomatoid granulomatosis and 1 of necrotizing sarcoid granulomatosis were reported. In this group of different diseases, characteristic pathological manifestations are inflammatory cellular infiltration of vessel wall combined with destruction and necrosis of pulmonary parenchyma. There was little difference in their clinical features. In most of the cases, fever and systemic symptoms related to lung and extrapulmonary organs were present. Correct diagnosis of these diseases is very important, because both the prognosis and therapy are different. As for the prognosis, it ranges from benign (necrotizing sarcoidal granulomatosis) to very malignant (lymphomatoid granulomatosis). The clinical features of each illness were reviewed with emphasis on their histopathologic findings. The therapeutic effect and final outcome were followed.


[Intervention measures for diabetes mellitus in community population]. A prospective study was made of two randomly selected community population, one given diabetes mellitus intervention measures, the other as control. The results showed that the intervention group had significantly lower incidence of diabetes mellitus than the control group. It is suggested that a diabetes mellitus control program be tried with the municipal hospital as the centre in collaboration with primary health care units at the periphery.


[Preliminary observations on effect of selenium yeast on high risk populations with primary liver cancer]. Two populations with high risk primary liver cancer (PLC), one of 226 cases with HBsAg carriers and another of 3849 first-relatives in the pedigree with high incidence of PLC, were randomly divided into the supplementing selenium group (selenium yeast 200 g Se1Tab/day) and the control group (common yeast 1 Tab/day), and were followed-up for four years and two years respectively. In the population with HBsAg carriers, no liver cancer occurred in the supplementing selenium group; where as the liver cancer incidence rate was 1573.03/10(5) in the control group. Among the first relatives. The liver cancer incidence rate in the supplementing selenium group was 219.37/10(5); and 553.15/10(5) in the control group. The results showed that the incidence of PLC in the supplementing selenium group was significantly lower than in the control group. This study indicates that selenium has distinct anti-PLC effect.


[Study of cytogenetic damages in peripheral blood of styrene exposed workers]. The three indices of chromosome aberration (CA), sister-chromatid exchanges (SCEs) and micronuclei were used simultaneously to ascertain the cytogenetic effects on eighty-three styrene exposed workers under current industrial hygienic conditions in two glass fiber reinforced plastics factories. Our results showed that exposure to styrene at a concentration of 129.3 mg/m3 (range 48.3-223.9 mg/m3) could result in an increase of the frequencies of CA and micronuclei but had little influence on the frequency of SCEs.


[Effect of noise on blood pressure of various types of rats]. Before the experiment, male Wistar rats were divided into two types (A and B) according to the different responses of their ECG and Heart Rate (HR) to 1 hour noise exposure: in type A, the ST segment elevated and HR decreased significantly during the exposure; in type B, both ST segment and HR showed no considerable variation. We exposed type A and B wistar rats and spontaneously hypertensive rats (SHRs) of 105 dB steady-state noise, 4 hours per day, 6 days per week. The results showed that after 3 weeks of noise exposure, the mean systolic blood pressure (BP) of type A rats was significantly higher than that of type B and control rats. This higher BP retained progressively till the end of observation (35 weeks); while there were not significant changes of BP in type B rats during the period of 35 weeks noise exposure. We also found that when exposed to noise for 14 weeks, the SHRs in exposure group had markedly higher mean systolic BP than those in control group. The results indicated that noise may affect BP of both Wistar rats and SHRs. There is probably a difference in the susceptibility of BP response to noise. The susceptibility of the BP of rats in type A to noise is greater than that of rats in type B.


[Application of multistate model to the analysis of relationship between cumulative occupational exposure and occurrence of disease]. The relationship between cumulative exposure and response used to be estimated by using the two state life table method. But since the occurrence of the response is related to the time factor after exiting exposure, this method may not provide correct description of this relationship. Based on multiple state model, this paper put forward a new method which modifies the effect of the time after exiting exposure on this relationship. The data from a cohort of 1113 underground male workers in a tin mine was taken as an example to illustrate the merit of this method.


[Experimental study on selenium preventing nasopharyngeal carcinoma]. In this study, we observed the effect of selenium (Se) on nasopharyngeal carcinoma (NPC) induced by dinitrosopi erazine (DNP) in rats through adding sodium selenite into drinking water. One hundred and sixty Wistar rats were divided into five groups: (1) blank control group (BG), no treatment; (2) Se control group (SG), given 50.7 mumol/L Se in drinking water for the first 3 weeks and then 31.7 mumol/L until the end of the experiment; (3) DNP control group (DG), injected subcutaneously 15mg/kg DNP twice a week from the 4th week to the 35th week; (4) Se prevention group (PG), given Se as done in SG and injected DNP as done in DG; (5) Se therapy group (TG), injected DNP as done in DG and given 50.7 mumol/L Se in drinking water from the 36th week to the end of the experiment. The experimental duration was one year. The result showed that there was no NPC in BG and SG and that the incidence of NPC in PG was reduced by 54.3% as compared with that in DG, which was significantly different (P < 0.01). In addition, the incidences of precancerous lesions of nasopharynx were significantly different between the two groups. But the incidences of NPC were not significantly different between TG and DG. In the process of carcinogenesis, the blood Se concentration of DG decreased. The blood Se concentration of rats could be elevated by supplementing Se in drinking water. Our result suggested that elevating the level of Se in rats can prevent the NPC.


[Food poisoning caused by mouldy rice contaminated with Fusarium and T-2 toxin]. An epidemic of food poisoning in human beings occurred in Tongxiang County, Zhejiang Province after eating mouldy rice contaminated with Fusarium and toxins. Continuous rainfall took place during the rice harvest season. The number of patients poisoned was 97, the rate of incidence was 58.8%. The incubation period was 10 to 30 minutes. The chief symptoms were nausea, dizziness, vomiting, chills, abdominal distension, abdominal pain and diarrhea. The fungi isolated from the mouldy rice were predominantly Fusarium heterosporum and F. graminearum. T-2 toxin was found in the mouldy rice and the highest content was 420 ppb.


[A study of vitamin inhibition on the mutagenicity of the antineoplastic drugs]. The inhibitory effects on the mutational specificity of antineoplastic drugs of 14 kinds of vitamin were tested with the method of mutational and anti-mutational synchoronous test, add S9 and no S9. Vit C, Vit B6, and nicotinic acid had distinct inhibitory effects on the mutational specificity of 6 antineoplastic drugs, namely, mitomycin C, bleomycin, fluorouracil, cis-Diaminodichloroplatinum, arabinosylcytosine and mustargen Vit K3 showed inhibitory effect to mitomycin C, fluorouracil, cis-diaminodichloroplatinum, and arabinosylcytosine but Vit AD, Vit B1, Vit B2, Vit Bco, Vit D3, Vit E, Rutin, Vit K1, Vit K4 and folic acid did not. The fact that Vit C, Vit B6, nicotinic acid and Vit K3 showed anti-mutational effects is of some significance with reference to clinical therapeutics and prevention of tumours.


[Study on the incidence of coal mine pneumoconiosis and lung cancer in Beijing coal mining district]. Thirty-two cases (20.13%) of primary lung cancer from 159 coal miner autopsies of Beijing coal mining area are reported in this study. The ratio of peripheral type to central type of lung cancer is 1.9:1; among them the adenocarcinoma is the most frequent (56.25%). Pathological examination shows that the diffuse interstitial type is the most common lung cancer. The occurrence of adenocarcinoma and the degree of lung fibrosis is related. The average number of ferruginous bodies is 190.2 +/- 8.06 in adenocarcinoma, 165.4 +/- 2.60 in squamous carcinoma, the difference is statistically significant (P < 0.05). The amount of trace elements-Fe, Al, Al/Si and Zn/Cu in lung with cancer is less than that without cancer. This article also discusses the relationship between coal mine pneumoconiosis with lung cancer of the formation of ferruginous bodies in the lung tissue of coal miner autopsies, which resembles the lung cancer combined with asbestosis. We also discussed the carcinogenesis of trace element in lung.


Bacteriuria in patients with glomerular diseases. In a comparative study of significant bacteriuria in an African population, 1.7% of 697 healthy subjects (10 females and 2 males) were found to have positive urine cultures. Of these, 5 subjects grew E. coli, 4 Klebsiella strains, 2 Staphylococcus aureus and 1 Serratia marcescens. Among 116 patients with glomerular disease, 15.5% (7 males and 11 females) yielded positive cultures. E. coli, Staph. aureus and Proteus species were commonly isolated organisms. There was a nine fold increase in prevalence of bacteriuria in patients with glomerular disease and in females, this correlated with the amount of protein lost per 24 hours. It is postulated that the presence of protein in urine per se favours bacterial growth and because of the high prevalence of bacteriuria in patients with glomerular disease, it is recommended that all such patients should be screened and treated appropriately.


Beef and dressed chickens as sources of enterotoxigenic Staphylococcus aureus in Nairobi. Staphylococcus aureus (S. aureus) isolates from beef carcasses, minced beef, and dressed chicken were assayed for production of enterotoxin A, B, C and D using reverse passive agglutination technique. The highest isolation rate was from chickens followed by minced beef. Chickens yielded the highest percentage of enterotoxigenic strains. Staphylococcal enterotoxin C (SEC) was the most frequently produced type from all the three sources while enterotoxin A ranked second and enterotoxin B third. These data show that chickens and minced beef are potential sources of food poisoning staphylococci in Kenya, and that increased handling of the products increases contamination suggesting that man is the major source.


In vivo effect of cadmium chloride on intestinal colonization of rats by Campylobacter jejuni. Campylobacter jejuni (10(8) C.F.U) fed intragastrically unto 18 laboratory rats (white whiskers) resulted in colonization of the 18 rats intestines and their eventual excretion of the organism for four months post infection. When 10(8) CFU of C. jejuni was mixed with 10 mu/ml of cadmium chloride (CdCl2) and fed immediately to another set of 18 rats, colonization of rats intestines was greatly reduced and C. jejuni was recovered from two (11%) out of 18 rats and the faeces were positive for C. jejuni for a maximum of 29 days. Six control rats given 1 ml of phosphate buffered saline (PBS) and a second set of another six control animals given 1 ml of PBS containing 10 micrograms/ml of CdCl2 gave negative result for C. jejuni throughout the experiment. This work depicts an in vivo effect of CdCl2 on C. jejuni and may be of importance in the control of C. jejuni colonization in experimental animals.


Household sanitation in Uasin Gishu district in Kenya. In rural Uasin Gishu District in 1990, 78.2% of the households had pit latrines, 11.3% ventilated improved pit latrines, 0.8% water-borne and 9.7% with no toilet facilities. On inspection, 97% of the toilet facilities were in use. Compost pits were present in 52.3% of the households. Utensil drying racks were found in 56.0% of the households. Compared to previous estimates, these levels represent a tremendous improvement in sanitation service coverage. It is recommended that the impact of water and sanitation programmes on health status needs to be evaluated. There is a need for studies to be done on the value of utensil drying racks in disease control.


Surgical treatment of chronic fissure-in-ano: a prospective randomised study. A prospective randomised study compared anal dilatation (n = 37), posterior internal sphincterotomy (n = 21) and lateral sphincterotomy (n = 20) in the surgical treatment of chronic anal fissures in 78 consecutive patients. All the operations were performed under general anaesthesia using standard techniques. Anal dilatation relieved anal pain early (immediate relief in 57% of patients; the mean pain-days +/- SD of 3.2 +/- 5.4 days). Anal fissures after this operation healed in a mean time +/- SD of 20.3 +/- 12.5 days, coming in second place to lateral sphincterotomy. Anal dilatation was followed by insignificant wound infection but its main disadvantage was a high rate of post operative anal incontinence (in 24.3% of patients). Fissurectomy and posterior internal sphincterotomy was followed by the longest period of post operative anal pain (mean +/- SD of 32.4 +/- 10 days) as compared to the other two operations. It was the least favourable operation. Lateral sphincterotomy was followed by early relief of pain (immediate relief in 95% of patients). It was not followed by wound infection. It had the quickest healing time for the fissures (a mean +/- SD of 14.7 +/- 8.7 days). It was followed by anal incontinence in only one patient. In conclusion lateral sphincterotomy was the most favourable operation and it is perhaps the operation of choice to perform in patients with chronic anal fissures needing surgical treatment.


Management of hand infection in Khartoum. One hundred and fifty patients with hand infection seen during 6 months period at Khartoum Teaching Hospital were studied. The disease is more common among young males manual and industrial workers (M:F = 2:1). Common types of hand infections were paronychia in (41%) of patients, volar infections in (30.6%) and subcutaneous infections in (30%) of patients. 30% of patients needed hospital admission including all diabetics (n = 15). Two patients had serious complications that resulted in above elbow amputation. The first was a diabetic with spreading cellulitis and the second was a mentally retarded with gas gangrene. Initial empirical antibiotic therapy was prescribed in 89% of patients and later was modified according to sensitivity results. 90% of patients needed surgical drainage. Bacteriological examination showed Staph. aureus in 51% of cultures and the staphylococcus was resistant to penicillin in 77% of cultures. Apart from two deaths, the rest of the patients had satisfactory outcome.


Observations from a cluster survey on seasonality in neonatal tetanus. This report presents the observations on seasonality and neonatal tetanus (NNT) mortality from a cluster survey on NNT mortality conducted in Kano metropolis, Northern Nigeria. A two stage cluster sampling method was used for the survey. There were 2,623 live-births with 1778 (67%) occurring in the dry season (October-May). The NNT mortality rate was 20.6/1000 live-births. The magnitude of neonatal mortality and NNT mortality were 47.3 and 30.8 per 1000 live-births respectively for the wet season. These were much higher than the comparative figures for dry season. There was, however, no significant association between seasonality and NNT mortality since the same trend was observed for non-NNT deaths.


The pattern of morbidity and its effects on productivity of factory workers in Kenya. A retrospective study was carried out from January to September 1990 in a factory that manufactures textiles in Eldoret, Kenya. Over the study period, 1400 factory workers had 303 episodes of illness resulting in a loss of 720 productive man-days. This is an incidence of 289 episodes of illness per 1000 workers per year. On average, each episode of illness resulted in 2.4 man-days loss. Of all the episodes of illness, 58.8% were attributable to infective and parasitic diseases, 10.9% to respiratory system disorders and 21.7% to other conditions. Malaria constituted 53.1% of all episodes of illness, acute respiratory infection (ARI) 10.9%, physical injuries 5.6%, gastro-enteric illnesses 3.4% and other conditions 21.7%. For the productive man-days lost, 53.2% were attributable to malaria, 12.8% to ARI, 5.7% to physical injuries and 28.3% to other conditions. Abortions and worm infections resulted in loss of 7.0 man-days per episode of illness, diarrhoea 3.2, myalgia 3.0, ARI 2.8, eye diseases 2.7 and the rest below the average of 2.4 days. Apart from the physical injuries, there were no other occupational illnesses in the textile factory workers. Episodes of illness that occur during the last and the first week of the month constitute 61.0% of all illnesses. Mondays had 24.4% of the episodes of illness, Sundays 7.9% with the other days of the week constituting an average 13.5%.


Sodium supplementation in very low birth weight infants fed on their own mothers milk: II. Effects on protein and bone metabolism. We determined serum calcium, inorganic phosphate, alkaline phosphatase, total protein and albumin levels in a group of 66 very low birth weight (VLBW) preterm infants seen at Kenyatta National Hospital. We used these parameters as markers to study the effect of sodium supplementation on protein and bone metabolism in VLBW infants fed on their mothers' milk. 41 of the infants were supplemented with 3 mMol/kg/day sodium chloride for a duration of six weeks of postnatal life. The remaining group were fed only on their mothers' milk. Results indicated significantly increased serum levels of calcium (P < 0.01) in the non-supplemented group while inorganic phosphate and total protein levels showed significant increase (P < 0.05) in the supplemented group. Both groups had increased levels of osteoblastic activity accompanied by high rate of protein synthesis in the supplemented group compared to the non-supplemented one. These findings together with a significant difference in growth rate (P < 0.01) observed between the two groups indicate that sodium supplementation may have a significant effect on the rate of bone mineralization and protein synthesis in VLBW infants.


Skin sensitivity patterns to inhalant allergens in Nigerian asthmatic patients. The pattern of skin sensitivity response to inhalant allergens in 746 Nigerian asthmatics and 92 normal controls tested over 10 years period is reported. Significant differences in reactions were observed in 7 of the 16 allergens routinely used in the study. House dust mite--dermatophagoides pteronyssinus gave the highest incidence of positive skin reaction, 58% asthmatics, 4.3% controls (P < 0.001). Other significant allergens were house dust 51.7%, feathers 24.4%; dog hair 12.9%, cat fur 11.9%, grass pollen 6.8% and flower pollen 6.3%. More males than females reacted to most of the allergens but this was statistically significant only for feather (P < 0.02). There was good correlation between history and skin sensitivity for most allergens. 82.3% of patients with positive skin test to D. pteronyssinus gave positive history of dust induced asthmatic attacks. Similar results were obtained for pollens: grass (86.3%), flower (83%) and feathers (57.7%). The correlation was however poor in respect of normal allergens (dog 30.6%, cat 36%). From the findings of this study there may be no point in routinely testing patients with a battery of allergens most of which may have no importance in the tropics. Attempts are however underway to incorporate local substances in skin testing materials. It is hoped that the results of this study will assist doctors who may not have access to skin test reagents in management of their asthmatic patients.


Early and medium-term morbidity of minilaparatomy female sterilisation in Kenya. A total of 1,521 clients undergoing voluntary surgical contraception via Minilaparatomy under local anaesthesia (L.A. Minilap) were prospectively followed up for early and medium-term morbidity. The commonest complaint was some degree of abdominal pain at 24.2%. Eight percent of these [corrected] reported that the operative pain was severe, but 92.0% reported minimal or moderate pain. The overall complication at 6 weeks was 4.1%, 17.5% of these were major and 82.5% minor, i.e. the rate for major complications was 0.7% and 3.4% for minor complications. There were no deaths. Female VSC via Minilaparatomy under L.A. is a relatively comfortable and easy procedure in well selected and counselled clients and carries minimal, usually non-recurrent morbidity.


The changing pattern of intussusception in northern Nigeria: an analysis of 85 consecutive cases. In many regions of Africa intussusception is the most common cause of intestinal obstruction next to strangulated hernia. More recent reports seem to indicate a change in the clinical pattern of the disease. This retrospective analysis covering a period of ten years is of 85 patients aged between 11 weeks and 50 years. There were 65 males and 20 females; 69 were children between 1 month and 15 years. The anatomical pattern of the disease has changed from being of the caecocolic type to the ileocolic variety while the pathology of the disease has remained largely unidentified. 32 patients had the ileocolic variety. 20 were ileocaecal, 14 colo-colic, 8 caecocolic, 8 ileo ileal, 2 jejuno jejunal, and 1 jejuno ileal. There were 2 ileal and 4 colonic neoplasms. There was a high rate of bowel resection (54/85) and 8 deaths.


Complications of combined antiepileptic therapy. Five hundred and fifty one epileptic cases in Taif Mental Health Hospital in Saudi Arabia were studied. Drug serum levels were determined by Enzyme Immunoassay. A combined anticonvulsant drug therapy was used frequently more than single drugs in the treatment of epilepsy. Percentage of combined therapy serum level was found higher than the therapeutic normal range of anticonvulsant drugs. Advantages and disadvantages of combined therapy as well as the importance of drug monitoring are presented.


Radiation doses to patients during contrast examinations of the gastrointestinal tract. Radiation doses received by patients undergoing radiological examinations of the gastrointestinal tract have been measured in 405 patients at two major hospitals in Nairobi using thermoluminescent LiF dosimeters. Skin-entry doses were found to be high at one of the facilities (A) and very high at the other (B). Barium meal delivered mean doses of 77 mGy (7.7 rad) and 558 mGy (55.8 rad) at facilities A and B respectively, while the corresponding mean values for barium enema were 93 mGy (9.3 rad) and 712 mGy (71.2 rad). Differences between the two hospital mean doses were highly significant (p < 0.001). Doses to the thyroid gland and the gonads were also generally higher than those reported in other similar studies. Poor performance of old and ill-maintained radiological equipment, among other possible factors, is suggested to be the main cause of excessive patient exposure. Radiation risks to patients are considered in the context of such high doses being received by a generally young patient population. The authors suggest that there ought to be limits on the extent to which social and economic considerations in the provision of radiological services should be allowed to compromise sound principles in the radiation protection of the patient. It is recommended that increased efforts be directed at establishing and supporting quality assurance programmes for the performance testing of radiological equipment in Africa.


Neurological complications of sickle cell anaemia at KNH: a five year retrospective study. In a five year retrospective study of 360 patients with homozygous (SS) sickle cell disease, eighteen (5%) were found to have neurological complications. Their ages ranged from 7 months to 21 years with a mean of 11.1 +/- 6 years. Of those with neurological complications, twelve (67%) of the patients had cerebrovascular accident, six (33.3%) convulsions, three visual disturbance; one sensorineural deafness, one cerebellar degeneration and the last one confusion and hallucinations. Four of the patients had multiple neurological complications. There was only one patient with recurrence of neurological complications. Two patients were hypertransfused and up to the end of the study period none of them had any recurrence. The pattern of neurological complications are similar to that observed in other studies. However, in this study, there were fewer recurrences of neurological complications.


Abnormal eating attitudes among a group of Nigerian youths: I. Bulimic behaviour. The prevalence of bulimic behaviour, a form of abnormal attitude to eating, was investigated among three different samples of Nigerian youths. Using the Binge-Eating questionnaire, a total of 649 females comprising high-school (n = 196), university undergraduate (n = 333) and college of education (n = 120) students were surveyed. A significant proportion of the total student population engaged in bulimic behaviours of bingle-eating (21.16%) and vomiting (22.20%). The various weight control methods they used include diet pills (4.70%), diuretics (6.60%), laxatives (19.50%) and vomiting (26.20%). These findings suggested that bulimic behaviour may be as much a non-western phenomenon as it is a western phenomenon.


Abnormal eating attitudes among a group of Nigerian youths: II. Anorexic behaviour. A survey of a total of 644 female Nigerian high-school, college and university undergraduate students was conducted to examine abnormal eating attitudes associated with anorexic behaviour. Using a cut-off score of 20 on the Eating Attitudes Test-26 (EAT-26), overall prevalence of disordered eating attitudes was found to be 14.1%. Prevalence figures for the high-school, university, and college samples were 18.6%, 9.1% and 21.7% respectively. These findings are comparable to those from western countries and suggests that nowadays abnormal eating attitudes associated with anorexia behaviour may be a universal phenomenon that transcends cultural boundaries, contrary to the earlier notion that they were restricted to western countries.


Quinine loading dose in severe Falciparum malaria at Kenyatta National Hospital, Kenya. From July 1989 to February 1990, 17 non-pregnant patients with severe falciparum malaria, aged 14 years and above received an initial intravenous quinine dihydrochloride loading dose of 20 mg/kg in 500 mls of normal saline or 5% dextrose infused over 4 hours followed by 100mg/kg infused 8 hourly for at least 24 hours. Sixteen comparable controls were similarly treated but without an initial loading dose. Oral quinine bisulfate 10mg/kg 8 hourly was substituted for a total of 7 days when patients were well enough. There was no significant difference in clinical and parasitological response between the two groups. Fever clearance time in hours was 44.00 +/- 13.92 (mean +/- SD) in the study group and 51.43 +/- 19.63 (mean +/- SD) in the control group (p > 0.05). Parasite clearance time in hours was 42.40 +/- 9.75 (mean +/- SD) in the study group and 47.05 +/- 7.69 (mean +/- SD) in the control group (p > 0.05). One patient from each group died. Mild toxic effects were common in both groups. Transient partial hearing loss occurred significantly more in the study than control group (p < 0.05). Hypoglycaemia during treatment occurred in 3 (18%) patients in the study group and 1 (6%) in the control group. The mean trough and peak plasma quinine levels in 3 patients per group was persistently higher than 9mg/L after first infusion. We conclude that though fairly well tolerated, quinine loading dose appears to have no advantage over the standard treatment for severe falciparum malaria at Kenyatta National Hospital, Nairobi, Kenya.


Maternal mortality in the Thyolo District of southern Malawi. The Sisterhood Method, a community-based survey technique, was used to estimate the Life Time Risk of a woman dying a maternal death in Southern Malawi. With this figure, the maternal mortality ratio for that area was calculated to be 409 deaths per 100,000 live births. The 4124 adults interviewed reported 150 maternal deaths in sisters. An in-depth questionnaire was then used to determine that 56% of these deaths occurred outside a health facility, largely due to lack of transportation or poor access to fixed health care facilities; 25% died from excessive hemorrhage; 20% from obstructed labour; 18% from abortion; 13% from sepsis; while eclampsia accounted for only 4% of the maternal deaths. This field experience with the Sisterhood Method technique combined with an in-depth questionnaire for determining causes of maternal deaths has provided useful information in a simple and cost-effective manner for use in planning intervention strategies designed to decrease maternal mortality.


Efficacy, tolerability and safety of isradipine (Lomir) in the treatment of mild to moderate Tanzanian hypertensives. Isradipine (Lomir) a new dihydropyridine calcium antagonist was evaluated for its efficacy, tolerability and safety among mild to moderate Tanzanian hypertensives. Twenty nine patients (7 males and 22 females), mean age 42.7 +/- 8.5 years entered active treatment phase, of the 16 week open label therapeutic trial. A mean decrease from base line in supine systolic blood pressure (SBP) of 17.6 mmHg (p < 0.001) and diastolic blood pressure (DBP) of 13.5 mmHg (p < 0.001) were achieved at the end of the study period. The corresponding changes from base line in standing SBP and DBP were 18 mmHg (p < 0.001) and 13.5 mmHg (p < 0.001) respectively. The efficacy was excellent or good in 84% and fair or none in 16% of the study patients. The tolerability of the drugs was excellent or good in 88.8% of patients, fair in 7.4% and bad in 3.8%. The mild side effects included headache, palpitations, tiredness and nocturia. But these improved with continued treatment. Isradipine (Lomir) at a dose of 1.25mg to 2.5mg twice daily is effective, safe and tolerable in mild to moderate hypertension.


Risk factors for HIV infection in gynaecological inpatients in Dar es Salaam, Tanzania, 1988-1990. A prevalence of 12.8% for anti-HIV-1 and a prevalence of 16.8% for anti-syphilis antibodies was found in 359 gynaecological inpatients admitted in the Department of Gynaecology and Obstetrics, Muhimbili University College of Health Sciences from 1988 to 1990. The highest HIV prevalence (17.3%) was observed in the youngest age group (14-20 years), whereas the highest syphilis prevalence (22.2%) was found in the oldest age group (> 45 years). Infections with HIV and syphilis were both significantly associated with variables related to sexual behaviour, such as marital status, age at first intercourse and number of sexual partners in the past ten years. After adjustment for these common risk variables linked to sexual behaviour, syphilis infection was still associated with a more than twofold higher risk of HIV infection (odds ratio (OR) = 2.60, p = 0.02) and trichomonas vaginalis infection with a nearly threefold higher risk (OR = 2.96, p < 0.001). These data characterize patients at risk for HIV infection among inpatients of a gynaecological department in East Africa, and indicate that effective measures to prevent sexually transmitted disease may reduce HIV transmission.


Some characteristics of serum phenytoin concentration, in black Zimbabwean volunteers. A study of phenytoin pharmacokinetics in 15 black healthy Zimbabwean volunteers with an average age of 22 to 44 years was performed. A dose of 200 mg (capsules) sodium phenytoin was administered orally to each subject. Peak phenytoin serum levels were detected six hours post-dosing at 2.98 +/- 0.53 micrograms/ml. The mean elimination half life (t1/2) was calculated at 40.2 hours with a range of 36.7 to 40.5 hours. The area under the curve was calculated to be 142.5 with a range of 118 to 192. Comparison of our results with those obtained by other workers is discussed.


Finger amputations in Tanzania.

Finger amputations in Tanzania. A survey of finger amputations carried out at Dodoma Regional Hospital, has shown that from 1983 to 1991, a total of 147 amputations have been done on 101 patients. They have been performed, mostly for causes that relate quite well with the living and working conditions of the inhabitants of Dodoma Region. Western causes of finger amputations have been responsible of ablation in a few patients in our series. Finger infection, usually with bone involvement, has been found to be the leading cause, followed by traumatic injuries, human bites and burns. Most patients were peasants, with a good number of illiterates among them, drawn from rural areas. They came late to hospital having been improperly managed in the early stages of the diseases. All these factors explain quite well why finger infections were, on admission, irrecoverable through medical means.


Allergic conditions in a general practice in Nairobi: a pilot study. This is a study of 574 randomly selected patients seen in a private practice. The incidence of allergic conditions was found to be 18.8%. The distribution of the allergic conditions was as follows: 35 suffered from bronchial asthma, 33 had dermatological allergic conditions, and 30 were reported as having drug allergies. A significant number of these patients had multiple allergic conditions.


Determination of foetal sex by ultrasound: state of the art. The determination of foetal gender is clinically indicated in sex-linked disorders. The reliability of ultrasound in prediction during the late second and third trimesters is well-established. Few studies attained high success rate in early second trimester. The variations in the success rate are due to the difference in size and gestational age of the published samples. Most studies have concentrated on the visualization of the external genitalia. Differentiation based on internal organs is not pursued. The ethical aspects have received attention by almost all workers in this field.


Effects of phosphate in the production of hemolysin in Vibrio parahaemolyticus. Vibrio parahaemolyticus is known to produce several types of hemolysin, the most document is the TDH and TRH. A new type of hemolysin whose expression is repressed by the presence of phosphate in the medium is reported.


Oral herpes simplex virus type 1 infection following cadaveric renal transplantation in a young type 1 diabetic female. The role of acyclovir: a case report. Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.


Properties and use of sulphur dioxide.

Properties and use of sulphur dioxide. This work analyses comprehensively the mechanism of action of sulphur dioxide in the process of wine-making. The use of sulphur dioxide is still a necessity for the storage and preservation of white wines. Nevertheless, the study of its physico-chemical and antimicrobial properties can make possible a large reduction of doses used even for white wines.


Microbiological aspects and technological need: technological needs for nitrates and nitrites. Nitrate and nitrite are used in meat and fish curing, and in the manufacture of certain cheeses. Nitrate itself has little antimicrobial effect and in most applications could be replaced by lower concentrations of nitrite. Further, improved hygiene diminishes the need for nitrite. The antimicrobial activity and technological needs for nitrate and nitrite are reviewed. It is concluded that the technological needs for nitrite in meat products stored at < 10 degrees C could be met by added nitrite concentrations of 50 mg/kg. The overall effect of nitrate in salted fish appears to be marginal. In such products, Vibrio parahaemolyticus does not grow at salt concentrations of 10% and food poisoning by this organism is not related to the absence of nitrate or nitrite; growth of Clostridium botulinum Type E (the predominant cause of botulism from fish products) is arrested by salt concentrations of 3-4%. Listeria monocytogenes in seafood cannot be controlled by nitrite. The use of nitrate in cheese production could be avoided, or at least reduced to a low level by avoiding silage with a high count of gas-producing Clostridia and hygienic milk collection.


Inactivation of Yersinia enterocolitica by nitrite and nitrate in food. The antimicrobial effects of sodium nitrite and sodium and potassium nitrate against Yersinia enterocolitica were investigated in solution and in treated pork meat. Potassium nitrate and sodium nitrate showed only feeble antimicrobial activity in cultures; no antimicrobial activity was detected with sodium nitrite. Conversely, all three salts displayed apparent antimicrobial activity in pork meat, possibly due to selective effects on competitive flora.


Food irradiation: is it an alternative to chemical preservatives? Generalizations about effects of irradiation may be misleading if the dose and commodities are not specified. Irradiation could be used for inhibition of sprouting, disinfestation, destruction of parasites in meat, to delay maturation of fruit and for pasteurization and sterilization. In some applications it could replace chemical sprout inhibitors, fumigants and chemical preservatives; in other cases it may have unique advantages e.g. in eradication of non-spore-forming pathogens in dry or frozen foods. Toxicological and nutritional evaluation has repeatedly confirmed the safety of irradiated foods. Effects on nutritional quality are frequently comparable with heat treatment and sometimes more conservative, particularly if oxygen is excluded. While food irradiation could be an alternative to chemical preservatives, misinformation has led to uncertainties as to its future.


Effect of some food preservatives on aflatoxin production. The effect of some food preservatives, such as sorbic (SA) and propionic (PA) acids, on aflatoxin production in synthetic media or in moistened (20%) wheat seeds, was investigated. The preservatives tested, added to synthetic media at sublethal concentrations both at the inoculum and after 5 days of incubation, stimulated aflatoxin production by Aspergillus parasiticus. Sorbic and propionic acids are metabolized by the fungus in vivo and in vitro. Lower concentrations of PA and SA (0.05 to 0.1% w/w) in wheat seeds are ineffective against both fungal growth and aflatoxin production, whilst the combined use of butylated hydroxy toluene (BHT), and PA or SA was more effective in controlling aflatoxin production than their use as single components.


Lysozyme: just an additive or a technological aid as well? The effects of lysozyme on coagulation of milk and cheese making were studied by means of the gelograph, tristimulus colorimetry, ANS-fluorescence (hydrophobicity) and SDS-PAGE. Lysozyme binding to caseins caused structural differences during coagulation and it is proposed that, if the products have similar qualitative properties, lysozyme might be used as a technological aid giving shorter clotting times and higher yields.


Surveillance of preservatives and their interactions in foodstuffs. The organization of food surveillance in the UK is described, in particular as it has been applied to preservatives and their interaction products in foods. Applications of nitrates and nitrites as preservatives are discussed, together with the consequential exposure of consumers to these anions and their reaction products. Analytical methods for the determination of volatile and non-volatile N-nitroso compounds are referred to in relation to the results in food surveillance studies. Concentrations of Apparent Total N-nitroso Compounds (ATNC) averaged 2900 micrograms(N-NO)/kg in fried smoked bacon compared with 2400 micrograms/kg in fried unsmoked bacon; of this, known volatile and non-volatile N-nitroso compounds accounted for only 10-20%. ATNC were not detected in cheeses except those manufactured with added nitrate when ATNC levels up to 210 micrograms(N-NO)/kg were detected. Further studies are needed to determine the identity and toxicological properties of the non-volatile N-nitroso compounds.


Reactions of nitrate and nitrite in foods with special reference to the determination of N-nitroso compounds. The stabilities of nitrate and nitrite in food systems and their reactions in such matrices are reviewed. Particular reference is made to reactions with haem proteins, smoke components and amines in foods, and the chemistry of formation of N-nitroso compounds from food components is discussed. Finally, the methodology available for determination of both volatile and non-volatile N-nitroso compounds is addressed.


Chemistry of sulphiting agents in food.

Chemistry of sulphiting agents in food. The main reason for the reactivity of sulphites in food is the nucleophilicity of the sulphite ion. The factors which determine the activity of this nucleophile are summarized and critically evaluated for concentrated systems, e.g. dehydrated foods. The distinction between free and bound sulphite is explained, and reversible binding of the additive in beverages and dehydrated foods is discussed with reference to simple theory of chemical equilibrium. The inhibition of non-enzymic browning reactions accounts for a large proportion of sulphite which undergoes irreversible reaction in concentrated foods. The mechanisms of reactions between sulphite species and intermediates in the model Maillard reaction, glucose+glycine, are considered in depth together with supporting kinetic data. An interesting feature is the fact that sulphites seem to catalyse the reactions they are added to control. Implications of this to the level of use of sulphite are discussed. Reaction products from the inhibition of Maillard browning include 3,4-dideoxy-4-sulphohexosulose which is formed initially and polymeric substances which arise from the reaction of sulphites with melanoidins. A proportion of sulphite added to food becomes converted to sulphate. Mechanisms of autoxidation are critically appraised in view of the presence of considerable concentrations of antioxidants in foods. The autoxidation of sulphite involves reactive free radical intermediates which include effective oxidizing agents. Thus, a pro-oxidant effect by the additive is possible and demonstrable in model system experiments.


Kinetics and mechanism of the reaction between 3-deoxyhexosulose and thiols. The kinetics of the reaction of 3-deoxyhexosulose, DH, with mercaptoethanol, ME, and glutathione, GSH, resemble those of the DH-sulphite reaction, but the stoichiometry of the DH-thiol reaction is 1:2 unlike that of the DH-sulphite reaction which is 1:1. However, the rate determining step in all these reactions is the spontaneous conversion of DH to a reactive intermediate, followed by a rapid reaction of this intermediate with the nucleophile. This is also true of the reaction between DH and N-acetylcysteine, NAC, but this thiol is less reactive than ME or GSH and less than one mole of NAC reacts with each mole of DH. Evidence for instability of NAC at pH 5.5 is presented. Aminothiols (cysteine, homocysteine, cysteamine) undergo a fast reaction with DH followed by a slow release of thiol. The initial reaction is probably formation of a thiazolidine. In the case of cysteine and homocysteine it is suggested that the subsequent slow step is a Strecker degradation reaction. The kinetic behaviour of thiols in cabbage homogenates is reported.


Kinetics of the inhibition of ascorbic acid browning by sulphite. Despite differences in the structures of aldoses and ascorbic acid, ASA, the non-enzymic browning of the latter involves intermediates similar to those found in Maillard browning. The kinetics of the sulphite-inhibited browning of ASA suggest that, under anaerobic conditions, the rate of reaction of sulphite species, S(IV), is of first order with respect to S(IV). The possibility that S(IV) could catalyse the hydrolysis of the lactone ring of ASA is considered by reference to D-glucono-delta-lactone. Evidence is presented to suggest that, under aerobic conditions, autoxidation of ASA leads to the oxidation of S(IV). The composition of melanoidins from ASA-glycine mixtures is compared with that from arabinose-glycine; the former contain 2 x 5 times more ASA-derived residues per glycine molecule than arabinose-derived residues per glycine molecule in the latter. The implications of these findings to the mechanism of ASA browning are discussed.


Kinetics of the sulphite-inhibited browning of fructose. Sulphite species, S(IV), inhibit the non-enzymic browning of fructose-amino acid mixtures. Inhibition of browning is accompanied by a loss of S(IV). The kinetics of the reaction of S(IV) in the system: fructose-glycine-S(IV) are described in detail; two distinct mechanisms have been identified. One involves only fructose in the rate determining step. The other requires fructose and both the glycine and S(IV). Some amines (e.g. taurine and ethanolamine) can markedly increase the rate of the S(IV)-independent step. Arginine and lysine are particularly effective for increasing the rate of reaction of S(IV) in the S(IV)-dependent reaction.


Kinetics of the reaction of sorbic acid with sulphite species. Under aerobic conditions, the reaction of sorbic acid with sulphite species, S(IV), involves a pH-dependent oxidative mechanism with the loss of S(IV). Sorbic acid is essential to the process. In the absence of air, a much slower nucleophilic addition of sulphite ion to undissociated sorbic acid takes place.


Reaction of sorbic acid in wheat flour doughs: reaction with thiols. The general characteristics of the reaction between sorbic acid and thiols are reviewed. Cysteine adds to the conjugated diene in position 5 to form the substituted 3-hexenoic acid. This is labile in acid solution, yielding a quantitative amount of sorbic acid. When wheat flour doughs are treated with sorbic acid and heated, a significant amount of the sorbic acid is not recovered on extraction with methanol. The use of acidified methanol leads to a quantitative recovery of the preservation and evidence is presented to suggest that sorbic acid-thiol adducts are formed. This is the first report of 'reversibly bound' sorbic acid in a food.


Browning prevention in fresh and dehydrated potatoes by SH-containing amino acids. N-Acetyl-L-cysteine and reduced glutathione were excellent inhibitors of browning of potatoes. In most cases, these two SH-containing compounds were more efficient inhibitors than L-cysteine and approached the effectiveness of sodium sulphite. These considerations suggest that N-acetyl-L-cysteine and reduced glutathione merit extensive evaluation as potentially useful inhibitors for food products.


Rapid method for the simultaneous GC quantitation of acids and sugars in fruits and vegetables. Rapid methods of analysis for the simultaneous determination of acids and sugars in fruits and vegetables using trimethylsilylation and gas chromatography are reported. The methods have been shown to be generally applicable, rapid, simple and cheap. Typical applications are shown involving the determination of a range of organic acids and sugars in carrot, potato, cucumber, tomato, apple, pear, grape, strawberry and citrus fruits.


Nutritional aspects of food preservatives. Despite the benefits attributed to food preservatives, some concern still remains regarding their safety and possible influence on nutrients. Surprisingly, there is quite a lack of scientific knowledge in this field. In order to describe a few examples, the effects of the extensively used sulphite on thiamine, folates, pyridoxal and other nutrients have been reported. Among its antibrowning effects, inhibition of ascorbic acid browning is also considered. As far as sorbic acid is concerned, notwithstanding its easy reaction with protein, probably the acid environment of the stomach determines the breakdown of the sorbic-protein adducts. Detoxication of nitrite by tocopherol and ascorbic acid leads, in the last case, to dehydroascorbic acid and its oxidative products with loss of vitamin activity. Any oxidizing substance destroys ascorbic acid, vitamin E and free vitamin A. Phosphates are largely used with different aims, including preservation, in food processing. Their antimicrobial activity is due to both a direct effect and an interaction with other antimicrobials. Sequestering capacity of phosphates and its nutritional implications are discussed. Also mechanisms of action of organic acids are reported, focusing on sorbic acid effects on single amino acids and proteins. Finally, the little information available about the potential impact of food preservatives on nutritional functions is presented.


Estimates of intakes: methodology and results of some studies carried out in Italy. The methods which may be applied to estimating population intakes of food additives are outlined. The applications in studies of the intakes of some preservatives and food colours in Italy are reported. It was concluded that there is a need to investigate comparability between the various methods used. The surveys carried out indicated that, in general, the levels of consumption of the additives studied did not present a health risk.


Food additives intake.

Food additives intake. The role of intake studies in the safety assurance process is discussed with reference to food preservatives and related to the variations in the authorizations for use.


Estimation of sulphite in food in France. Estimates have been made of the consumption levels of sulphites in foods in France using two methods, a global and a segmented protocol. The global method gave an estimated average intake of 20 mg SO2/day/capita; the segmented method gave estimates of 1.96 mg/day/capita for non-consumers of alcoholic beverages and 31.5 mg/day/capita for average consumers of cider, beer and wine. The risk of exceeding the Acceptable Daily Intake concerns only regular consumers (40-75 years old) of alcoholic beverages, particularly wine, the main vector. The global approach appears to be a simple and useful method for estimating intakes.


Safety aspects of food preservatives.

Safety aspects of food preservatives. The use of food preservatives, such as benzoic acid, nitrites, and sulphites, as antimicrobials, and butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), ascorbic acid and tocopherols, as antioxidants, has probably changed food production patterns and eating habits more than has the use of any other class of food additive. These food preservative chemicals confer substantial benefits on man, not only by the preservation and increased palatability of food, but also by affording protection against the pathological effects of reactive oxygen species (ROS) which are associated with cancer, cardiovascular disease and aging. Nevertheless, although most preservatives are now considered to be without potential adverse effects and are classified as GRAS, there have been problems concerning the safety of some of these chemicals, including the possibility of allergies from benzoic acid and sulphites, the formation of carcinogenic nitrosamines from nitrites, and the possible rodent carcinogenicity of BHA and BHT. The mechanisms of this toxicity at high dosage, the roles of the cytochromes P450, and the generation and scavenging of ROS in the toxicity of these chemicals, are reviewed and discussed.


In vitro model for the evaluation of toxicity and antinutritional effects of sulphites. The food preservatives, sulphur dioxide and its salts, are known to present some toxic, mutagenic and antinutritional effects; in fact they interact with a number of nutrients, e.g. some vitamins, notably thiamine (Th) and folic acid (FA). The effect of different concentrations of sodium bisulphite in cell culture media has been studied in vitro on a human cell line, HEp-2, deriving from a carcinoma of the larynx. Moreover, the sulphites have been tested with different levels of Th and FA with the aim of elucidating how much the cellular response depended on either the anti-nutritional effect or the toxicity of sulphites. Cell growth has been taken as an index of cytotoxicity and measured both as total protein content and as colony-forming ability. With no Th and FA in the culture medium, a clear decrease of cell growth was observed either with or without addition of sodium bisulphite. A dose-dependent reduction of protein content was detected in cells treated with 10, 50, 100, 200, 250 or 500 microM sodium bisulphite. Moreover, when the cells were treated with 10 or 100 microM of this compound, the colony-forming ability was reduced both in number and colony size. As far as the interaction of the two vitamins with sodium bisulphite is concerned, when these nutrients were present in the medium at 0.5, 1.0, 1.5, 2.0 or 2.5 mg/l, a similar growth profile, determined from their concentration, was observed in treated and control cells, the growth levels being affected by the sodium bisulphite contents. At higher levels of Th and FA, the growth index was still increasing only in treated cells, this phenomenon being particularly evident in cultures treated with 200 microM sodium bisulphite. The colony-forming ability was reduced in controls but still increased in treated cells at the highest concentration of vitamins.


Formaldehyde and hexamethylenetetramine as food additives: chemical interactions and toxicology. Formaldehyde (FA) and hexamethylenetetramine (HMT) are used in cheese production to control gas-forming clostridia; FA also occurs naturally in some foods at levels of 1-20 mg/kg. The toxicology of FA and HMT are briefly discussed together with their reaction in foods. The most abundant end-product of FA in cheese is spinacine derived from the N-terminal histidine residue in gamma 2-casein. Acute and short term toxicological studies on spinacine enable a No Observed Effect Level of 300 mg/kg body weight/day to be determined, leading to an Acceptable Daily Intake (ADI) for man of 3 mg/kg body weight/day. From these data a Tolerance Level (TL) of 1800 mg spinacine/kg cheese can be derived, leading to a Safety Margin (SM) of 12.9. It is concluded that there is no appreciable health risk from consumption of cheese made using formaldehyde (Grana Padano) or hexamethylenetetramine (Provolone).


The regulation of preservatives in the European Community. Community regulation of preservatives is based on Council Directive 64/54/EEC of 5 November 1963, which defined 'preservatives' and established an exclusive approved list which Member States could permit. In some instances the Directive set limits on conditions of use and general purity criteria; specific purity criteria were established in a second Directive 65/66/EEC. The base Directive has been amended twenty-four times and that relating to purity criteria three times. The approved list has two parts, listing separately substances whose primary function is preservative and those whose primary function is other than preservative but which have a secondary preservative effect. Separate labelling laws require that the presence of additives, including preservatives, be declared. Permitted preservatives must be safe and technologically effective. Safety evaluation is carried out by the Scientific Committee for Food; technological effectiveness is assessed by experts from governments of Member States, food and chemical industry and the Commission. In future, preservatives will be encompassed by the general additives 'Framework Directive' which addresses areas including: exclusive permitted lists; lists of foodstuffs to which and conditions under which additives may be used; purity criteria; methods of analysis and sampling procedures. The Framework Directive also specifies criteria to be satisfied before an additive may be approved including guidance on what constitutes 'need', appropriate safety evaluation (and re-evaluation as necessary). Agreed conditions of use will need to ensure that ADIs are not compromised; where these are sufficiently high, the concept of 'quantum satis' might be applied whereas low ADIs may necessitate limitations on number of uses and levels of addition.


Toxicology of sulphiting agents. I: Animal studies. Oral toxicity studies of sulphite in animals are briefly reviewed. On the basis of a chronic toxicity/carcinogenicity study of sodium metabisulphite in rats JECFA established an ADI of 0.7 mg SO2/kg using a safety factor of 100. The effects of sodium metabisulphite (1% Na2S2O5) on the composition of semi-purified rat diets during storage for at least three months have been studied. Under these conditions sulphite induced rancid off-flavours in diets containing unsaturated fats. The feeding of such stored sulphited-diets to rats resulted in growth retardation and diminished food efficiency. The extractability of the lipids from these diets was markedly reduced. Extraction with hexane, followed by ethanol extraction did not remove the toxic factor(s). It was suggested that sulphite in stored semi-purified diets may react with unsaturated fats leading to the formation of polymers of unsaturated fatty acids and/or other toxic substances. It is recommended that special attention is paid to the fatty acid composition of sulphited foods to be stored.


[Hygienic rationale maximum allowable concentrations of 1,2,4-triazole in atmospheric air]. Toxicological study of the 1,2,4-triazole determined the maximum one-time MAC of it in the ambient air at level of 0,1 mg/m3, average daily MAC of it - 0,05 mg/m3.


[Evaluation of the maximum allowable concentration of iron in the water]. Experimental study of the iron allergenic effects on animals and pediatric examination of 130 schoolchildren in regions with high level of the iron in the water showed safety of the iron Mac in the water at the level of 0,3 mg/1.


[Risk of halophilic morbidity in connection with the eutrophication of the seashore]. Significant role of the littoral eutrophication in the growth of parahemolytic vibrio caused acute gastrointestinal disturbance- halophilosis was described.


[Toxicological characterization of new nitrification inhibitors]. Study of the two new nitrification inhibitors HMDI and TMDI showed a low toxicity. The lower toxicity with single intragastric administration was 485 mg/kg for HMDI, and 460 mg/kg for TMDI.


[Chronic effect of fluorides on the status of the pancreatic insular apparatus of workers]. Decreasing of the insulin concentration and increasing of the C-peptide level in blood serum of 72 workers of cryolytes industries detected by radioimmunological method. These changes were caused by the fluorine intoxication of workers.


[Influence of enzyme industry products on the human immune system]. Enzyme industry products had significant allergo- and immunogenic effects on human body, manifesting by allergic dermatitis and respiratory forms of allergy. Most negative effects on immune system had alkaline protease 1 and 2, salizymelipase, neutral protease and protease C. Problems of diagnosis and modernizations of in-plant conditions were discussed.


[Hygienic characteristics of the flour mill working environment]. The fusariotoxins' content in the in-plant air of the flour mill and its effect on the workers' health status were investigated.


[Food habits and work capacity indices of adolescents learning the specialties of locksmith and automobile mechanics]. Complex assessment of the pupils studied the metalworker of motorcar repair service. Profession was given in aspect of their diet. Some recommendations based on the assessment were worked out.


[ Approaches to the radiation hygienic assessment of "soil components" of plutonium]. By the Pathway-analysis the correlation coefficients between the plutonium isotopic contamination of soil and the human radiation dosage were defined.


[Preparation of human placenta microvillous membrane and the study of its transferrin receptor]. Human placenta microvillous membrane (PMM) was prepared by differential centrifugation and by sucrose gradient centrifugation, and the transferrin receptor (TfR) was studied using the receptor radioassay with 125I-transferrin as a radioligand. The factors affecting ligand-receptor binding reaction and the characteristics of TfR were also studied. The result showed that there was no significant differences (P > 0.1) in specific binding rates of 125I-transferrin to its receptor between the two membrane preparations, indicating that both of them could be used for TfR analysis, but the method of differential centrifugation was more simple and less time consuming. The study of TfR in sixty cases showed that the TfR binding sites on PMM and Bmax were 3.53 +/- 1.98 x 10(12) sites/mg membrane protein and 6.33 +/- 4.21 x 10(-12) mol/mg membrane protein, respectively. The Kd was 4.95 +/- 3.39 x 10(-9) mol/L, and the highest specific binding was 26% with nonspecific binding less than 3%. The conditions for ligand-receptor binding reaction were optimized when the concentrations of membrane protein and the 125I-transferrin in each test tube were 50 micrograms and 50,000 cpm (specific radioactivity being 2109 kBq/micrograms transferrin) respectively the incubation time was 30 min, and the concentration of polyethylene glycol added for separating B/F was 12% (W/V). transferrin binding to its receptor was characterized by high affinity, high specificity and being saturated.


[Colony hybridization with digoxigenin labelled DNA probe]. A simple, rapid method for colony hybridization has been developed. The DNA probes were labelled by digoxigenin. Hybridization signal was detected by enzyme-linked immunoassay reaction. The results showed that this method is sensitive and reproducible, and it can be used for colony hybridization instead of isotopic methods.


[Human blood stain identification using DNA amplification technique]. DNA was extracted from human's and 15 different species of mammals' dried blood stains as well as from camel hair roots. DNA amplification was carried out using primers of Alu 9.1 and Alu 9.2. The results have indicated that this method can be used for the identification of human's dried blood stain under general condition.


[The detection and analysis of leptospiral DNA in patients' serum of early leptospirosis by polymerase chain reaction and DNA hybridization with digoxigenin-AMPPD]. We have detected and analysed the leptospiral DNA in serum of patients with early Leptospirosis from the epidemic area of China by PCR and DNA hybridization with Digoxigenin (Dig)-3-(2'-Spiroadamantane)-4-methoxy-4-(3"-phosphoryloxy)- phenyl-1,2-dioxetane (AMPPD) to develop a sensitive, specific and reliable technique for the early diagnosis of leptospirosis, and full satisfactory results have obtained. Fourteen serum specimens from patients with leptospirosis proven by blood culture and serological test were prepared according to Boom's methods for PCR test, and oligonucleotide primers, named G1 G2, were obtained from a genomic library of leptospira interrogans. PCR amplification with serum specimens was performed. Each cycle of amplification consisted of denaturation at 94 degrees C for 1 min, annealing at 55 degrees C for 1 min and elongation at 72 degrees C for 2 min. Each sample was subjected to 32 cycles. The amplified DNA were separated by electrophoresis with 2% agarose gel and hybridized with the homologous DNA probe labelling with Dig-AMPPD by means of Southern blotting. All of 14 samples revealed the presence of leptospira and the strong signals were visualized with homologous DNA probe hybridization by Southern blotting. Negative and positive controls appeared correctly. The DNA fragment generated from PCR amplification homologically hybridized with the DNA of 16 strains which are from Yasudas' genomic species and represent the different genomic groups of leptospires. The single recognized band (about 400 bps) from 6 out of the 16 strains has come out which are representative of the principal strains in Sichuan, China.(ABSTRACT TRUNCATED AT 250 WORDS)


[Detection of leptospiral DNA in the serum of 175 patients with early leptospirosis by polymerase chain reaction]. We have developed a sensitive assay for leptospira, using the polymerase chain reaction (PCR). On the basis of the published nucleotides sequence of 23S rRNA gene from Leptospira interrogans serovar canicola strain Moulton, primers were chosen to produce an amplified fragment of 123 bp. Primer A: 5'GAT CTA ATT CGC TGT AGC AGG3' and primer B: 5'ACT TTC ACC CTC TAT GGT CGG3' Eight different svs. of Leptospira interrogans could all be detected by PCR, but the DNAs from L. biflexa. Leptonema bacteria, virus and human could not produce the specific amplified fragment. The assay detected approximately 10 fg of purified leptospiral DNA and 1 microliter serum of experimental animal. Positive results were obtained from simulated positive samples containing a single organism leptospiral DNA. The diagnostic test (proved by "gold standards": Clinical diagnosis; blood culture and MAT) showed that the sensitivity was 92.00%; the specificity 94.35%; the accuracy 92.54%; the positive predictive value 98.17%; the negative predictive value 78.13%; the positive likelihood ratio 16.25; and the negative likelihood ratio 0.0848. The diagnosis of early leptospirosis by using PCR may become a significant addition to diagnostic means.


[Serum apolipoprotein E levels in 238 healthy adults and 161 hyperlipidemic subjects in Chengdu area]. The serum apoE levels in 238 healthy adults in Chengdu are aware determined by radioimmunodiffusion (RID) assay. The average apoE level was 3.98 +/- 0.98 mg/dl (chi +/- s). The result was basically identical with other reports. There is no difference in sex, and the level has a tendency to increase with age. One hundred and sixty-one hyperlipidemic subjects (including types IIa, IIb, IV and V were compared with the normals. Their serum apoE levels increased by different percentages depending on the type of hyperlipidemia. The percentage of increasing was especially higher in types V and IIb. The content of apoE in serum positively correlated with serum triglyceride (r = 0.65, P < 0.01) and with serum total cholesterol (r = 0.50, P < 0.01).


[Preparation of antigen and antibody against aflatoxin B1]. Carboxymethyloxime of aflatoxin B1 (AFB1) was synthesized by refluxing AF B1 with carboxymethoxylamine hemihydrochloride for 4 hours in the presence of pyridine. AF B1-BSA (antigen) was made successfully by coupling AF B1-oxime with bovine serum albumin (BSA) in the presence of a water soluble carbodiimide. The rabbits were immunized with the artificial immunogen which had been purified by dialysis. The titers of antisera were determined by indirect enzyme-linked immunosorbent assay (ELISA) which was developed by ourselves. The highest titer was 1:100,000.


[Establishment and preliminary application of competitive ELISA using monoclonal antibody against Trichinella spiralis]. Monoclonal antibody competitive ELISA was devised with a highly specific McAb (2G8) against T. spiralis. Among 20 rabbits infected with T. spiralis experimentally. 35% (7/20) were positive on the 17th day post infection (PI); 100% positive on the 31st day PI. No cross reaction was found with 29 sera of rabbits infected with other kinds of helminth. The dynamic antibody titer of five infected rabbits sera were studied with this method. The change may be helpful to judge the state of infection. In short, anti-T. spiralis McAb competitive ELISA can be regarded as a sensitive and specific immunological diagnostic method for T. spiralis infection.


[Changes in glomerular polyanions and ultrastructure induced by protamine in rats]. Perfusion of rat kidneys with polycation protamine, resulted in pathologic alterations of glomeruli very similar to those observed in minimal change nephrotic syndrome in human. In the experimental model, colloidal iron stained kidney tissue sections were analyzed quantitatively by image analyzer and stereology in combination with the observation of other glomerular ultrastructure. The mean thickness of foot processes and the foot processes making up the volume fraction of glomerular capillary were determined. The studies showed that there was a significant decrease in glomerular polyanions of kidneys perfused with protamine as compared with that of the control group (P < 0.01). The glomerular alterations included swelling and fusion of foot processes and narrowing or loss of filtration slits. Electron-dense particles formed by binding of protamine to polyanions were seen primarily in the lamina rara externa of glomerular basement membrane and also along the lamina rara interna and on the foot process surface, which showed the distribution feature of glomerular filter. These results suggest that the ultrastructure alterations of glomeruli may result from the neutralization of polyanions by perfusion with protamine.


[Prognostic significance of nuclear DNA measurement with flow cytometry for laryngeal squamous cell carcinomas]. DNA ploidy, S% and proliferative index (PI) of carcinomatous cell were evaluated with FCM in 41 patients with laryngeal primary squamous cell carcinomas which were operated on in our department during the period between Jan. 1979 to Oct. 1987. The results showed that DNA aneuploidy was identified in 65.85% of the cases (27/41) and patients with aneuploid carcinomas had higher S% (mean +/- standard: 23.22 +/- 9.57%), higher PI (mean +/- standard: 37.59 +/- 9.57%) and higher rate of relapse and/or metastasis than those with diploid tumours (55.55% vs 11.77%, P < 0.025). Patients with aneuploid carcinomas also correlated with an unfavorable prognosis compared with those with diploid tumors. Cases with aneuploid and diploid carcinomas had 66.11% and 92.86% respectively for two years postoperation survival rate; 46.74% and 92.86% respectively for five years postoperation survival rate (Log-rank test: chi 2 = 5.96, P < 0.025). We conclude that nuclear DNA measurement with flow cytometry is of important significance in estimating prognosis and guiding treatment for laryngeal squamous cell carcinomas.


[Studies of outer membrane protein profiles by SDS-PAGE for Campylobacter jejuni in an epidemiological investigation]. The characteristics of outer membrane protein profiles of 41 strains of Campylobacter jejuni from various sources by SDS-PAGE was studied. Seven and nine OMP patterns were differentiated respectively by the presence or absence of six outer membrane protein bands and by the number and size of the molecular weight of the major protein bands. Comparing the OMP patterns of the strains from human with those from animals, the authors inferred that chickens and other animals might be one of the sources for the human infection of Campylobacter jejuni in this district. A comparison between the OMP patterns of the strains from diarrheic children and those from healthy carriers suggested that the pathogenesis of Campylobacter jejuni be possibly associated with the outer membrane proteins. Using the techniques, the authors studied the infection of Campylobacter jejuni in a nursery. The result showed the infection was sporadic and of multi-sources, as evidenced by the multi-patterns of the outer membrane protein profiles. It also indicates that the person-to-person transmission plays a significant role in the infection of Campylobacter jejuni.


[Effects of zinc deficiency and vitamin D deficiency on bone calcification and development of rats]. Zinc deficiency rat model was made by feeding zinc deficiency diet. The level of bone calcium of the zinc deficiency rats was significantly lower than that of the control rats. Their bone cortex was thinner and bone density decreased. The counts of their cartilage cells and hypertrophic cells of epiphyseal plate were less frequent, and the diameter of their hypertrophic cells was smaller than that of the controls. It suggested that zinc deficiency caused defective bone calcification which was similar to that in vitamin D deficiency. Zinc deficiency seemed to hinder the linear growth of long bone and might be the cause of dwarf.


[Mutagenesis study of ethylmethane sulfonate with shuttle vector plasmid pZ189]. Shuttle vector plasmid pZ189 was used as a molecular tool and the SupF inserted in the plasmid was worked as a target gene for mutagenesis study. The host cells (E. coli MBM 7070) with pZ189 were treated with ethylmethane sulfonate (EMS) and plated on the selective media containing X-gal (5-bromo-4-chloro-3-indolyl-beta-D-galactoside) and IPTG (isopropyl-beta-D-thiogalactoside). The SupF and the LacZ amber mutant carried by the host cells complemented each other and thus made the colonies blue on the selective media. However the colonies derived from the SupF mutants changed the colour from blue to white. The mutant frequencies in a series of experiments with different concentrations of EMS were estimated. Furthermore, the DNA isolated from 5 SupF mutants was digested with restruiction enzyme Hha I. It suggests that the 214 bp Hha I fragments containing mutant SupF could be distinguished from their wild type counterparts by temperature-gradient gel electrophoresis under optimal conditions.


[Relation between the occurrence of malignant arrhythmia during acute myocardial ischemia and the weight of ischemic myocardium in goats]. The coronary collateral circulation of goat is very spare, so myocardiac ischemia model of goat can simulate the patient previously with normal coronary circulation and suddenly developing complete occlusion of coronary arteries. In this study 80 Chengdu goats were used, and the branches of their left coronary artery were ligated. Ventricular tachycardia (VT) developed in 23 goats and ventricular fibrillation (VF) in 39 goats. VT and VF both occurred in the early phase of acute myocardial ischemia, and both had 6 min as the median time of onset. In 71 cases data on the weight of myocardiac ischemic area were collected, in which the weight percentage of ischemic area relating to the ventricles of 34 goats with VF was significantly higher than that of 37 goats without VF (35.4 +/- 2.4% vs 19.5 +/- 1.9%). After coronary ligation, 9 cases directly precipitated into VF which could not be defibrillated. In the remaining 62 cases, the weight percentage of ischemic area of 21 cases with VT was higher than that of 41 cases without VT (32.9 +/- 2.8% vs 20.9 +/- 2.1%). The relationships between the incidence of VT or VF and the weight percentage of ischemic area were fitted with logistic curve. The likelihood of occurrence of VT or VF is increased as the weight percentage of ischemia area goes up.


[Effects of adrenergic agonist on population spike in CA1 region of hippocampal slices from partial and full kindled rats]. Effects of adrenergic agonist on population spike (PS) amplitude were studied extracellularly at CA1 region of hippocampal slices from partial and full kindled rats with coriaria lactone (1-1.25 mg/kg, two days a time, i.m.) and compared with those from control rats. 5 mumol/L norepinephrine (NE) increased PS; 50 mumol/L NE decreased it slightly. 5 mumol/L isoproterenol (ISO) increased PS. 100 mumol/L phenylephrine (PE) decreased it. The effects of increasing and decreasing PS could be antagonised by beta and alpha adrenergic antagonists, respectively. The effects of NE and PE on PS amplitude showed no significant difference between the control and kindled rats. The effect of beta-adrenergic agonist ISO on PS amplitude in hippocampal slices from partial kindled rats was less than that of control (P < 0.01). The effect of ISO on PS of full kindled rats was partially recovered.


[Effects of calcium channel blocker verapamil on hippocampal kindled seizures induced by coriaria lactone in rabbits]. Eighteen fully kindled rabbits, whose epilepsy had been produced by intrahippocampal (i.h.) injections of 2 microliters of diluted solution containing 0.32 or 0.55 micrograms of coriaria lactone (CL), were separated into three groups. One of them was used as the control group. For seizure, all animals were given CL (0.6-1 micrograms/2 microliter i.h.). Ten minutes later, the verapamil (VR) group of six rabbits was treated with VR (1.5 or 2 mg/kg i.m. 2.5 or 5 micrograms/2 microliters i.h.); the normal saline (NS) group (six rabbits) received 0.8 ml/kg (i.m., in the same volume as that of the VR 2 mg/kg injection) or 2 microliters (i.h.) of NS; the control group of six received neither VR nor NS. The experiments were made once every eight days. Hippocampal EEGs of all animals were recorded by telemetric method and their behavior after injection was observed continuously in 4-7 hours. The results of the experiment indicated that the i.h. administration of 2.5 or 5 micrograms/2 microliters of VR is effective on hippocampal kindled seizures induced by CL in rabbits, but the curative effects of the i.m. administration of 1.5 or 2 mg/kg of VR were less notable than those of the i.h. administration.


[Age-related morphological changes in the suprachiasmatic nucleus of the rat hypothalamus]. A comparative ultrastructural investigation of the hypothalamic suprachiasmatic nuclei (SCN) of young, adult and senescent SD male rats was carried out. The neurons and neuroglial cells in SCN of the senile rats displayed more lipofuscin (Lipo) accumulation in comparison with those of the younger animals. Golgi apparatus (Gol) of the three age groups converted from well-ordered cisternae to irregular ones with extensive dilatation and vacuolization. More neuroglial cells with broader somatic membrane appositional to that of neuron participated in satellitosis in the senile age group. Some unusual structures such as special arrangements of the rough endoplasmic reticula and multilamellar neuroglial envelope (Mge) wrapping neurite were encountered in the perikarya of some neurons or SCN neuropile respectively.


[A computer program for the power spectra analysis of biomedical signals]. This paper presents a useful program for the power spectra analysis of biomedical signals on a microcomputer. The frequency spectra to show the allocation of frequency were calculated from the acquired biomedical signal via a window algorithm and the real signal special handling. The frequency spectra became normalized power spectra through algorithm and could be displayed on a monitor or printer in the mode of histogram. We have got good results using this program to compute the power spectra of phrenic nerve discharges from the rabbit.


[High performance liquid chromatographic determination of hydroxyphenytoin in human urine]. A high-performance liquid chromatographic method for the determination of p-hydroxyphenytoin (p-HDPH) in human urine was reported. Following acid hydrolysis of urine sample at 90 degrees C for 1 h, an internal standard, nitrophenol, was added. The sample was extracted with n-hexane-ethyl acetate (50:50), and organic layer was evaporated. The residue was dissolved in methanol and chromatographed on an Ultrasphere-ODS column, using a mobile phase of phosphate buffer (0.03 mol/L, pH 6.0): methanol (65:35) at a flow rate of 0.8 ml/min. The eluent was monitored at 240 nm. The standard curve was linear within the range 5.0-200 micrograms/ml (r = 0.9998). Analytical recovery rates were 102.8 +/- 7.3% (p-HDPH 9.70 micrograms/ml, n = 5) and 104.9 +/- 6.4% (p-HDPH 54.70 micrograms/ml, n = 5). The cumulative recovery of p-HDPH in 0-12 h volunteers' urine samples accounted for 20% of the oral dose of 100 mg phenytoin sodium.


[A method for acquiring newborn larvae of Trichinella spiralis in vitro]. This paper reports a simple method for acquiring numerous newborn larvae of Trichinella spiralis in vitro. Adults of T. spiralis, collected from small intestine on rats which were infected with infective larvae separated from mice infected experimentally, were put into tissue culture bottle containing M199. Then the bottles were incubated in CO2 incubator (37 degrees C, 5% CO2) for 15-20h. The newborn larvae were collected by passing through filtration, centrifugation and repeated wash. The results showed that this method is effective in terms of the activity of the adults and newborn larvae and the amount of larvae gained. The method in economical and can control bacterial contamination to a certain extent and extract ES antigen of adults and newborn larvae from the culture solution.


[Simultaneous analysis of vitamin B complex by least square UV-spectrophotometry]. Simultaneous analysis of VitB1, VitB2 and VitB3 in Vitamin B Complex tablets was made by least square UV-spectrophotometry. The results showed that the contents of VitB1, VitB2 and VitB3 could be calculated by computer with least square method using 12 absorbances of 239, 241, 257, 259, 261, 263, 266, 269, 270, 279 and 281 nm wavelengths. The reclamation of VitB1 was 101.4% (CV% = 0.88, n = 3), of VitB2 98.5% (CV = 0.43, n = 3), and of VitB3 101.3% (CV% = 0.15, n = 3).