1052854
Photodynamic effects of chloroaluminum phthalocyanine tetrasulfonate are mediated by singlet oxygen: in vivo and in vitro studies utilizing hepatic microsomes as a model membrane source.
Chloroaluminum phthalocyanine tetrasulfonate (AlPcTS) is a promising photosensitizer for the photodynamic therapy (PDT) of cancer. In this study, we investigated the in vivo and in vitro photodestruction of hepatic microsomal membranes by AlPcTS and studied the role of reactive oxygen species in this process. Irradiation of hepatic microsomes prepared from AlPcTS-pretreated SENCAR mice to approximately 675 nm light resulted in rapid destruction of cytochrome P450 and associated monooxygenase activities, and enhancement of lipid peroxidation in a light-dose-dependent manner. The specificity of AlPcTS and light dependency on photodestruction of microsomal membranes was confirmed by Western blot analysis. Similar results were obtained when AlPcTS was added in vitro to a suspension of hepatic microsomes prepared from control animals followed by irradiation to approximately 675 nm light. Among the quenchers of singlet oxygen, superoxide anion, hydrogen peroxide, and hydroxyl radical, only the quenchers of singlet oxygen such as sodium azide, histidine, and 2,5-dimethyl furan afforded substantial protection in a dose-dependent manner against AlPcTS-mediated photodestruction of cytochrome P450 and associated monooxygenase activities, and photoenhancement of lipid peroxidation under both in vivo and in vitro conditions. These results suggest that lipid-rich microsomal membranes may be the potential targets of cell injury by AlPcTS-based PDT and that this process is mediated by singlet oxygen.
46117096
ras protein p21 processing enzyme farnesyltransferase in chemical carcinogen-induced murine skin tumors.
Farnesylation of ras protein p21 is crucial for the protein's membrane localization, which is essential for its cell-transforming activity, which in turn is thought to be critical for the ultimate induction of cancer. The cytosolic enzyme farnesyltransferase plays a major role in posttranslational modification of p21, but the level of farnesyltransferase activity in mammalian tumors and its relationship to the processing of cytosolic p21 that leads to tumorigenesis are unknown. We report here that farnesyltransferase activity was significantly higher in chemical carcinogen-induced benign skin papillomas in SENCAR mice than in the epidermises of control animals. The enzyme is primarily epidermal in origin, and kinetic studies with cytosol from epidermis and papillomas showed that the reaction was linear with respect to time, substrate concentration, and protein content. Skin papillomas showed significantly elevated levels of both cytosolic and membrane-bound Ha-ras p21, whereas far lesser cytosolic and almost negligible amounts of membrane-bound p21 were present in the epidermis of control mice. There was a positive correlation between increased enzyme activity in papilloma cytosol and the processing of overexpressed cytosolic Ha-ras p21 for its localization to membrane.
5785486
Identification of the site of photocross-linking formed in the absence of magnesium nucleotide from SH2 (Cys-697) in myosin subfragment 1 labeled with 4'-maleimidylbenzophenone.
The site of photocross-linking between Cys-697 (SH2), prelabeled with 4'-[14C]maleimidylbenzophenone, and the 50-kDa segment of myosin S1 on irradiation in the absence of nucleotide has been determined by isolation of the 20-50-kDa adduct and subsequent tryptic proteolysis. Isolation and partial sequencing of the radioactively labeled peptide indicate that the site of cross-linking is Arg-239. This result indicates that, in the absence of nucleotide, Arg-239 resides at about 1.0 nm from SH2 and, on the basis of the recent work of Sutoh and Hiratsuka (Sutoh, K. and Hiratsuka T. (1988) Biochemistry 27, 2964-2969) places Arg-239 at no more than 1.45 nm from either Lys-184 or Lys-189 of the nucleotide-binding "glycine-rich" loop prior to the binding of nucleotide.
35457752
Nordihydroguaiaretic acid, an inhibitor of lipoxygenase, also inhibits cytochrome P-450-mediated monooxygenase activity in rat epidermal and hepatic microsomes.
Nordihydroguaiaretic acid (NDGA), a plant lignan and phenolic antioxidant, is a known lipoxygenase inhibitor. In this study, we investigated the effect of NDGA on rat epidermal and hepatic monooxygenase activity and its interaction with rat hepatic microsomal cytochrome P-450. The addition of NDGA to epidermal microsomes prepared from control and 3-methylcholanthrene (3-MC)-pretreated rats and hepatic microsomal preparations from control, 3-MC-pretreated, and phenobarbital (PB)-pretreated rats resulted in a concentration-dependent inhibition of aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin O-deethylase (ERD) activities. The 50% inhibitory dose for NDGA ranged from 4.1 x 10(-5) to 13.1 x 10(-5) M for AHH and ERD activities in these microsomal preparations. The addition of NDGA to hepatic microsomes prepared from PB-pretreated rats resulted in spectral changes characterized by absorbance maxima at 380 nm and minima at 414 nm, typical of type I binding difference spectra. It also showed time- and concentration-dependent inhibition of the binding of carbon monoxide to dithionite or NADPH-reduced cytochrome P-450. We speculate that perhaps hydroxyl groups present in NDGA play an important role in inhibiting the monooxygenase activity and suggest that NDGA may have potential as an antimutagen and/or anticarcinogen. Furthermore, caution must be exercised in elucidating the role of lipoxygenase in metabolic pathways based solely on the criterion of inhibition by NDGA.
37464296
Introduction to Special Issue on Molecular Basis for Cancer Prevention with Bioactive Food Components in Nutrition and Cancer--an International Journal.
The advance of technology and understanding of the process of cancer development suggests that the reported lesser incidence and death due to cancer in countries other than the Western and European countries might also be due to under- diagnosed and under-represented cases. Further, increases in life span as well as ignorance about the disease puts populations in South and South East Asian countries at higher risk to develop cancer. With the increasing rate of cancer incidence every year in non -Western countries, cancer is estimated to become the deadliest disease in coming decades. Conventional chemo- and radio-therapies during the past three decades have not been able to contain the disease, and also have serious side effects. Many natural agents, especially small molecules from plants are non-toxic, easily available and may have anticancer potential. Thus, screening phytochemicals as anticancer agents could be a better approach in cancer prevention and treatment. This chemoprevention approach may have translational significance for prevention and treatment of cancer. 
 
Therefore to emphasize the potential role of phytochemicals in cancer prevention and therapy, it was our privilege to host the International Symposium on Recent Advances in Cancer Research: Therapeutics to Chemoprevention, at Central University of Gujarat (CUG), Gandhinagar. The conference was co-organized by the University of Colorado Denver, USA; University of Pittsburgh, USA; University of Oklahoma, USA, during 8–9 February, 2012. Modern biological strategies, specifically the latest developments for the targeted prevention and treatment of cancer via dietary, natural and synthetic agents were discussed in detail. The symposium also emphasized the translational aspect of cancer chemoprevention strategies for various cancers. 
 
The symposium deliberations include the ideas for combinatorial chemoprevention by phytochemicals as a promising approach for cancer control and emerging trends for the use of herbal radio-modulators to sensitize the cancer cells for apoptotic cell death. Many bioactive phytochemicals such as silibinin, benzyl isothiocyanate, anthocyanidins, nexrutine, tocopherol, etc. were discussed for their in vivo efficacy in animal tumor models, associated mechanisms and translational potential. Targeting tumor microenvironment with small molecules was found promising and having translational potential for prostate and breast cancer chemoprevention. 
 
The novel work and ideas presented at the symposium were helpful in guiding the research orientation of scientists, especially the young researchers who will be benefitted at all levels of their career development. Since chemoprevention of cancer is becoming an attractive approach for controlling cancer, we felt that the deliberations of this symposium should reach to the wider section of the researchers. Therefore, it was planned to bring out a special issue on Molecular Basis for Cancer Prevention with Bioactive Food Components in Nutrition and Cancer – An International Journal. We appreciate the researchers for contributing their novel work and ideas to this special issue. We are grateful to the Editor of Nutrition and Cancer – An International Journal, for his initiative to bring out this special issue on this relevant topic. We believe that this volume will be enlightening for the researchers working in the area of cancer chemoprevention.
6837472
Apoptosis is an early event during phthalocyanine photodynamic therapy-induced ablation of chemically induced squamous papillomas in mouse skin.
Photodynamic therapy (PDT) is a promising new modality to treat malignant neoplasms including superficial skin cancers. In our search for an ideal photosensitizer for PDT, Pc 4, a silicon phthalocyanine, has shown promising results both in in vitro assays and in implanted tumors. In this study we assessed the efficacy of Pc 4 PDT in the ablation of murine skin tumors; and the evidence for apoptosis during tumor ablation was also obtained. The Pc 4 was administered through tail vein injection to SENCAR mice bearing chemically induced squamous papillomas, and 24 h later the lesions were illuminated with an argon ion-pumped dye laser tuned at 675 nm for a total light dose of 135 J/cm2. Within 72-96 h, almost complete tumor shrinkage occurred; no tumor regrowth was observed up to 90 days post-PDT. As evident by nucleosome-size DNA fragmentation, appearance of apoptotic bodies in hematoxylin and eosin staining and direct immunoperoxidase detection of digoxigenin-labeled genomic DNA in sections, apoptosis was clearly evident 6 h post-PDT at which time tumor shrinkage was less than 30%. The apoptotic bodies, as evident by the condensation of chromatin material around the periphery of the nucleus and increased vacuolization of the cytoplasm, were also observed in electron microscopic studies of the tumor tissues following Pc 4 PDT. The extent of apoptosis was greater at 15 h than at 6 and 10 h post-PDT. Taken together, our results clearly show that Pc 4 may be an effective photosensitizer for PDT of nonmelanoma skin cancer, and that apoptosis is an early event during this process.
9282919
TB or TB plus vasculitis: Occam versus Hickam.
41765492
Effects of magnesium taurate on the onset and progression of galactose-induced experimental cataract: in vivo and in vitro evaluation.
Cataract, a leading cause of blindness, is characterized by lenticular opacities resulting from denaturation of lens proteins due to activation of calcium-dependent enzyme, calpain. Magnesium (Mg(2+)) plays an important role not only in maintaining a low lenticular calcium (Ca(2+)) and sodium concentration but also in preserving the lens redox status. Taurine has also been shown to reduce lenticular oxidative stress. Present study evaluated the anticataract effects of magnesium taurate in vivo and in vitro. Among the five groups of 9 Sprague Dawley rats each, two groups received 30% galactose diet with topical (GDMT) or oral treatment (GDMO) with magnesium taurate. Two groups received 30% galactose diet with topical (GDT) or oral vehicle (GDO). Remaining 1 group received normal diet (ND). Weekly slit lamp examination was done during 21 days experimental period and then all rats were sacrificed; Ca/Mg ratio and antioxidant parameters including reduced glutathione (GSH), catalase and superoxide dismutase (SOD) activities were measured in the isolated lenses using ELISA. In the in vitro study, 2 groups of 10 normal rat lenses were incubated in Dulbecco's Modified Eagle's Medium (DMEM) with galactose while 1 similar group was incubated in DMEM without galactose. In one of the groups, galactose containing medium was supplemented with magnesium taurate. After 48 h of incubation, lenses were photographed and Ca(2+)/Mg(2+) ratio and antioxidant parameters were measured as for in vivo study. The in vivo study, at the end of experimental period, demonstrated delay in the development of cataract with a mean opacity index of 0.53 ± 0.04 and 0.51 ± 0.03 in GDMO (p < 0.05 versus GDO) and GDMT (p < 0.01 versus GDT) respectively. Histopathological grading showed a lower mean value in treated groups, however, the differences from corresponding controls were not significant. Lenticular Ca(2+)/Mg(2+) ratio with a mean value of 1.20 ± 0.26 and 1.05 ± 0.26 in GDMO and GDMT was significantly lower than corresponding controls (p < 0.05) and in GDMT no significant difference was observed from ND. Lenticular GSH and catalase activities were significantly lower and SOD activity was significantly higher in all galactose fed groups. However, in GDMT, GSH and catalase were significantly higher than corresponding control with mean values of 0.96 ± 0.30 μmol/gm lens weight and 56.98 ± 9.86 μmol/g lens protein respectively (p < 0.05 for GSH and p < 0.01 for catalase). SOD activity with mean values of 13.05 ± 6.35 and 13.27 ± 7.61 units/mg lens protein in GDMO and GDMT respectively was significantly lower compared to corresponding controls (p < 0.05) signifying lesser upregulation of SOD due to lesser oxidative stress in treated groups. In the in vitro study, lenses incubated in magnesium taurate containing medium showed less opacity and a lower mean Ca(2+)/Mg(2+) ratio of 1.64 ± 0.03, which was not significantly different from lenses incubated in DMEM without galactose. Lens GSH and catalase activities were restored to normal in lenses incubated in magnesium taurate containing medium. Both in vivo and in vitro studies demonstrated that treatment with magnesium taurate delays the onset and progression of cataract in galactose fed rats by restoring the lens Ca(2+)/Mg(2+) ratio and lens redox status.
21512706
Experience with ARDS caused by tuberculosis in a respiratory intensive care unit
ObjectiveAcute respiratory distress syndrome (ARDS) is an important cause of morbidity and mortality in intensive care units. Tuberculosis (TB) commonly causes respiratory failure in patients with extensive pulmonary parenchymal involvement, but it is a rare cause of ARDS. We report our experience of TB presenting with ARDS.MethodsRetrospective analysis of 187 patients admitted with a diagnosis of ARDS over the previous 7 years. Data are presented in a descriptive fashion using mean±SD or median (range).ResultsNine (4.9%) of 187 patients had ARDS secondary to tuberculosis. All patients were mechanically ventilated. The diagnosis was made on clinico-radiological grounds and confirmed later using fiberoptic bronchoscopy and transbronchial biopsy in seven patients, and lymph node biopsy and examination of the joint aspirate in the remaining two. All patients were empirically started on anti-tubercular therapy with a median time to initiation of therapy being 3 days (range 2–8 days). Three patients had multi-organ dysfunction syndrome (MODS) without any evidence of bacterial infection. Seven of nine (77.8%) patients survived; two died because of severe ARDS, MODS, and respiratory failure.ConclusionsTuberculosis is an uncommon but definite cause of ARDS, and in patients with ARDS of obscure aetiology where the clinical features suggest tuberculosis as the inciting cause, antitubercular therapy should be started empirically and the diagnosis actively pursued later.
27154557
Ambulatory blood pressure and cardiovascular events in chronic kidney disease.
Hypertension is an important risk factor for adverse cardiovascular and renal outcomes, particularly in patients with chronic kidney disease (CKD). This review compares blood pressure (BP) measurements obtained in the clinic with those obtained outside the clinic to predict cardiovascular and renal injury and outcomes. Data are accumulating that suggest that ambulatory BP monitoring is a superior prognostic marker compared with BP values obtained in the clinic. The use of ambulatory BP monitoring can detect white-coat hypertension and masked hypertension, which results in less misclassification of BPs. Ambulatory BP monitoring is a marker of cardiovascular end points in CKD. Nondipping is associated with proteinuria and lower glomerular filtration rate. Although nondipping is associated with more end-stage renal disease and cardiovascular events, adjustment for other risk factors removes the prognostic significance of nondipping. For patients with CKD who are not on dialysis, 24-hour ambulatory BPs of less than 125/75 mm Hg, daytime ambulatory BP of less than 130/85 mm Hg, and nighttime ambulatory BPs of less than 110/70 mm Hg appear to be reasonable goal BP targets. In the management of hypertension in patients with CKD, control of hypertension is important. Ambulatory BP monitoring may be useful to assign more aggressive treatment to patients with masked hypertension and withdraw antihypertensive therapy in patients with white-coat hypertension. Ambulatory BP monitoring can refine cardiovascular and renal risk assessment in all stages of CKD. The independent prognostic role of nondipping is unclear.
45066226
Patients on three times-weekly haemodialysis have increased mortality during the long, 2-day interdialytic interval
Commentary on: Foley RN, Gilbertson DT, Murray T, et al. Long interdialytic interval and mortality among patients receiving hemodialysis. N Engl J Med 2011;365:1099–107.[OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4]

People on long-term haemodialysis are dialysed three times-weekly such as on Mondays, Wednesdays and Fridays. Accumulation of volume and toxins over the longer 2-day interdialytic interval (eg, Friday–Monday) may provoke excess deaths. The cohort study by Foley et al asked the question whether compared with other days, morbidity and mortality is increased during the long interdialytic interval.

The participants were 32 065 adults in the USA who participated in the End-Stage Renal Disease (ESRD) Clinical Performance Measures Project at the end of calendar years 2004 through 2007. Patients were excluded if they were not receiving haemodialysis three times weekly. The outcomes were various causes of morbidity and mortality and their relationship with the …

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