Methylparathion, carbaryl and aldrin impact on nitrogen metabolism of prawn, Penaeus indicus

Changes in hepatopancreas, muscle and gill tissue nitrogen metabolic profiles were studied in a penaeid prawn, Penaeus indicus, following its exposure to sublethal concentrations of methylparathion, carbaryl and aldrin. In all the insecticide exposed prawn tissues, Ammonia levels were significantly increased and a shift in the nitrogen metabolism towards the synthesis of urea and glutamine was observed. Inhibition of glutamate oxidation to ammonia and alpha-ketoglutarate by glutamate dehydrogenase suggests a mechanism whereby hyperammonemia is reduced by minimizing the addition of further ammonia to the already existing elevated ammonia pool. Increased alanine and aspartate aminotransferases demonstrates the onset of gluconeogenesis. Mechanisms to detoxify the ammonia by enhancing the synthesis of urea and glutamine at the cellular level was observed in the selected tissues pave way for the survivability of prawns in insecticide polluted environs.

Toxic impact of lindane on aspartate and lindane aminotransferase activity levels of midgut gland of marine prawn, Penaeus indicus

In vitro addition of lindane (organochlorine insecticide) causing significant changes in the protein and amino acid metabolic profiles of midgut gland by interfering with the aminotransferase system of Penaeus indicus.

Tropical eosinophilia: clinical and physiological response to diethylcarbamazine

Fifty patients with tropical eosinophilia were studied clinically and physiologically, before and after a standard 3-week course of diethylcarbamazine. Before treatment the main physiological abnormality was a reduction in the carbon monoxide transfer factor. One month after the start of treatment most patients had shown a marked symptomatic improvement, but peripheral blood eosinophilia persisted in 52%, radiographic abnormalities in 44%, cough in 22% and chest signs in 8%. Significant improvement was noted in almost all aspects of lung function including blood gases, but the mean values for forced expiratory volume in one second, forced vital capacity, transfer factor and transfer coefficient continued to be significantly lower than predicted values. This study demonstrates the incomplete reversal of clinical, haematological, radiological and physiological changes in tropical eosinophilia one month after starting a 3-week course of diethylcarbamazine.

Significance of natural polymerized albumin and its receptor in hepatitis B infection of hepatocytes

Lack of information regarding the presence of native albumin polymer in serum and its structural similarity to the one produced by glutaraldehyde treatment casts doubt on the postulate that hepatitis B virus attachment to hepatocytes is mediated through polymerized albumin. We used a sandwich enzyme-linked immunosorbent assay with murine monoclonal antibodies raised against glutaraldehyde-polymerized albumin to detect native albumin polymer in human serum and its cross-reactivity with other albumin polymers. Presence of polymerized albumin receptor on the HepG2 cell was studied by radioreceptor assay. Purified hepatitis B virus and synthetic peptide analogous to part of pre-S2 sequence (120-145) were used to study polymerized albumin-dependent attachment of the virus to HepG2 cells. Antibodies raised against pre-S2 peptide were used to inhibit the pre-S2 and hepatitis B virus attachment to HepG2 cells. Glutaraldehyde-treated polymerized albumin was found to be immunologically cross-reactive with native albumin polymer. Its levels were found to be significantly raised in sera of patients with liver diseases. Polymerized albumin has specific saturable receptor on HepG2 cells with two classes of binding sites of different equilibrium dissociation constant (Kd1 = (16 +/- 9.6)pmol/L and Kd2 = (1,019 +/- 172)pmol/L. Albumin monomer was unable to compete for the polymerized albumin receptor sites on HepG2 cells. Anti-pre-S2 antibodies inhibit hepatitis B virus and pre-S2 binding to hepatocyte by 40% and 70%, respectively. Added extraneous polymerized albumin and the antibody against it did not interfere with virus attachment to HepG2 cells.

Toxic impact of phosphamidon on protein degradation in phasic and tonic muscles of marine prawn, Penaeus indicus (H. Milne Edwards)

Levels of various protein fractions, (sarcoplasmic, myosin, actin, non-collagen and collagen) and the rate of their degradation by proteases were studied in phasic and tonic muscles of marine prawn, Penaeus indicus following acute (2 d) and chronic (15 d) exposure to sublethal concentration of phosphamidon. During exposure, greater decrease in sarcoplasmic protein fraction was observed in phasic muscle as compared to other myofibrillar proteins. But the sarcoplasmic protein content showed an elevation in tonic muscle. The changes in protein fractions were more pronounced during acute exposure than chronic exposure both in phasic and tonic muscles. These changes were correlated with the elevation of the acidic, neutral and basic protease activities during acute and chronic exposure. Free amino acids were increased during acute exposure, while they showed a significant decrease during chronic exposure in both the muscles. These results indicate that protein metabolism in both phasic and tonic muscles was significantly altered following phosphamidon exposure. These differential responses observed at acute and chronic exposure indicate the operation of compensatory mechanisms to mitigate the phosphamidon toxic stress.

Toxic impact of phosphamidon on acid phosphatase of prawn, Metapenaeus monoceros (Fabricius)

Activity levels of acid phosphatase (ACPase) in midgut gland and muscle tissues of penaeid prawn, Metapenaeus monoceros were studied after exposure to selected sublethal concentrations of phosphamidon after acute and chronic exposure. Phosphamidon was found to elevate the activity levels of ACPase in the selected tissues. The rate of elevation of ACPase is dose-dependant and is more at higher concentrations. Acute and chronic exposure to phosphamidon creates disturbances in the normal functioning at the cellular level in the tissues of prawn, M. monoceros.

In vitro inhibition of Ca+2 ATPase by methylparathion in prawn: a kinetic approach

After in vitro addition of IC50 concentration of methylparathion on Ca+2 ATPase in nervous and hepato-pancreatic tissues of prawn were studied. The inhibitory pattern of Ca+2 ATPase elucidate the interaction of methylparathion with ATPase system. The significant decrease in maximal velocity (Vmax) without appreciable change in apparent Michaelis-Menten constant (Km) suggests that the impact of methylparathion on Ca+2 ATPase is independent of substrate and is of a classical non-competitive type.

Aldrin and lindane impact on acid and alkaline phosphatase activities of prawn, Metapenaeus monoceros: in vitro study

Activity levels of acid and alkaline phosphatases in hepatopancreas, stomach, muscle, gill and brain tissues of penaeid prawn, Metapenaeus monoceros were studied after in vitro addition of different concentrations of aldrin and lindane, the organochlorine insecticides. The activity levels of both these enzymes were inhibited significantly in all the tissues of prawn and the degree of inhibition is increased with increase in the concentration of insecticide. The significant inhibition creates disturbances in the normal functioning such as disturbances in the normal functioning such as disturbances in protein synthesis and different biochemical lesions in selected tissues of prawn, M. monoceros.

Impact of methylparathion and malathion on cholinergic and non-cholinergic enzyme systems of penaeid prawn, Metapenaeus monoceros

The nervous tissue AChE, BUChE and glutaminase activity levels were significantly inhibited, whereas glutamine synthetase activity, acetylcholine and glutamine contents were increased significantly following the sublethal exposure of prawn, Metapenaeus, monoceros to methylparathion and malathion. During OPI exposure ammoniagenesis was triggered by increased deamination of purines and oxidative deamination of glutamate. This results in the hyperammonemia. As a consequence of hyperammonemia, the OPI exposed prawn tissue have adopted the suitable mechanisms to detoxity the ammonia by enhancing the synthesis of urea and glutamine. From the study, it has been observed that 10 days of reclamation period is not enough but the prawn nervous tissue showed efficient mechanisms for the detoxification or biodegradation of OPI molecules, which will pave way for the successful survival prawns.

Inhibitory effects of snuff extract on ornithine decarboxylase and aryl hydrocarbon hydroxylase activities in relation to cell proliferation of mouse tongue epithelial cells

Effect of snuff extract (SE) on cell proliferation as measured by 3H thymidine (TdR) uptake, induction of ornithine decarboxylase (ODC) and aryl hydrocarbon hydroxylase (AHH) was studied in primary embryonal mouse tongue cultures. Cultures treated with SE in combination with 7,12-dimethylbenz(a)anthracene (DMBA) showed inhibition of cell proliferation and decrease of ODC and AHH activities, compared to control, DMBA, and DMBA + 12-O-tetradecanoylphorbol 13-acetate treated cultures.

Hepatitis B virus X protein produced in Escherichia coli is biologically functional

The hepatitis B virus X gene product trans activates transcription from a variety of viral and cellular regulatory elements. We expressed the complete, nonfused X protein in Escherichia coli and showed it to be active in trans activating a human immunodeficiency virus long terminal repeat-linked chloramphenicol acetyltransferase reporter gene.

Keloids and diabetes in a family

An interesting familial association of keloids with diabetes mellitus in three successive generations is reported. Keloids did not develop if the injection site was changed to the anterior abdominal wall.

The effects of calcium channel blockers on cyclosporine and its metabolites in renal transplant recipients

Although calcium channel blockers have been reported to increase trough cyclosporine (CsA) blood levels, few studies have systematically examined the effects of calcium channel blockers on CsA pharmacokinetics. In the present investigation, complete pharmacokinetic profiles of CsA and its major metabolites (M1, M17, and M21) were determined in 11 verapamil-treated patients, 7 nifedipine-treated patients, and in 78 controls. Whole blood and urine levels were analyzed using high-performance liquid chromatography. Verapamil caused a 45% increase in CsA area under the curve, maximum concentration, steady-state concentration, and trough level. Metabolite 17 levels were increased in a parallel fashion, suggesting that altered CsA bioavailability rather than decreased metabolism may have caused the higher CsA levels in verapamil-treated patients. However, verapamil-induced reductions in CsA metabolism by other routes could not be ruled out. No changes in CsA or its metabolites were observed in nifedipine-treated patients. Unlike previous reports in patients treated with higher CsA doses, verapamil and nifedipine did not improve renal function in the present study. Nevertheless, the increase in CsA blood levels seen with verapamil may enhance the therapeutic cost-effectiveness of this agent in hypertensive renal transplant recipients.

Mechanism, pathophysiology, diagnosis, and management of renal transplant rejection

In recent years, there has been a steady progress in basic research (immunogenetics and cellular immunology) that helped us in understanding the mechanisms underlying allograft rejection. Several laboratory tests were developed, and the results were shown to correlate with clinical rejection. However, most of these studies have not found a place in clinical practice because of their nonspecificity, lack of sensitivity, time lag, added expense, and inconvenience. The commonly employed diagnostic tests (i.e., renal transplant ultrasound and 131I hippuran scintigram) are helpful in differentiating rejection from other causes of graft malfunction. The specific renal parenchymal disease, such as acute or chronic rejection or de novo or recurrent glomerular disease, contributing to graft malfunction can only be diagnosed by renal histopathologic study. Because hyperacute and accelerated acute rejections are irreversible and necessitate graft nephrectomy, measures should be taken to prevent this problem. High-dose corticosteroids still remain the mainstay of therapy for acute cellular rejection. In the case of steroid-resistant rejections, treatment with ALG or OKT3 appears promising. As there is no effective therapy for chronic allograft rejection, usual measures of delaying the progression of chronic renal failure should be employed, and patients should be advised to return to maintenance dialysis before they develop uremic symptoms. If current experiments demonstrating selective immunosuppression with monoclonal antibodies are found successful in human trials, one can expect further improvement in the outcome of renal transplantation.

Enhanced immunogenicity of a sequence derived from hepatitis B virus surface antigen in a composite peptide that includes the immunostimulatory region from human interleukin 1

The effect on immunogenicity of coupling the immunostimulatory nonapeptide sequence (residues 163-171) from human interleukin 1 beta (IL-1 beta) to a small immunogen was examined. A 21-amino acid sequence spanning positions 12-32 on the large protein of hepatitis B surface antigen was chosen as a model. Three peptides were synthesized corresponding to the IL-1 beta-derived sequence [peptide IL-(163-171)], the hepatitis B surface antigen-derived sequence [peptide S1-(12-32)] and a composite peptide that included both these sequences separated by a spacer of two glycine residues [peptide S1-(12-32)-IL-(163-171)]. In an in vitro thymocyte proliferation assay, both peptides S1-(12-32)-IL-(163-171) and IL-(163-171) showed comparable activity, whereas peptide S1-(12-32) was inactive. Groups of five to seven mice each from C3H/CH, BALB/c, SJL/J, and C57BL/6 strains were immunized with equimolar amounts of either peptide S1-(12-32), peptide S1-(12-32)-IL-(163-171), or a mixture of peptides S1-(12-32) and IL-(163-171), and sera were screened for anti-S1-(12-32) antibodies. In all strains, peptide S1-(12-32)-IL-(163-171) elicited an increased primary and secondary anti-S1-(12-32) antibody response compared to the other two groups. Further, peptide S1-(12-32)-IL-(163-171) also induced an increased number of responders to primary immunization, though the number of responders was quantitative in all groups following secondary immunization. At least part of the enhanced immunogenicity of the S1-(12-32) sequence in peptide S1-(12-32)-IL-(163-171) appears to be due to augmented T-helper cell activity. These results suggest that coupling of the immunostimulatory IL-1 beta-derived sequence in tandem with an immunogen may confer inbuilt adjuvanticity.

Further studies on the neuroleptic profile of manassantin A

In an earlier preliminary study, manassantin A, a neolignoid from Saururus cernuus was found to show neuroleptic type activity in mice when given by the i.p. route. It blocked the stereotypy and hyperactivity caused by amphetamine at doses comparable to those of haloperidol, but unlike the latter, did not show catalepsy or ptosis at atoxic doses. In the present study, a more detailed comparison of manassantin A with haloperidol and in some cases with chlorpromazine and reserpine using a variety of neuroleptic parameters and by various routes of administration is described. Results of the present study clearly show that the drug is readily absorbed from various routes of administration and shows many of the patterns of neuroleptic activity. Manassantin A was comparable to haloperidol in many of the tests but unlike the latter, did not produce antiadrenergic or anticholinergic effects. Manassantin A was found to bind weakly to calf caudate membranes (IC50 3500 nM) while haloperidol (IC50 5 nM) and chlorpromazine (IC50 50 nM) inhibited [3H]haloperidol binding. Manassantin A also did not affect the dopamine-induced adenylate cyclase activity in rat caudate nuclei (IC50 greater than 10,000 nM) while haloperidol (IC50 700 nM) and chlorpromazine (IC50 350 nM) inhibited the enzyme synthesis. These biochemical and behavioral tests suggest that manassantin A exhibits a selective neuroleptic profile and may be considered to behave as an atypical agent.

Respiratory carcinogenesis of nitroaromatics

The carcinogenic potential of 1-nitropyrene, a major mutagenic constituent of diesel-exhaust particles, was investigated using a hamster respiratory-carcinogenesis model. The specific aims of the investigation were to assess the activity of 1-nitropyrene as a complete carcinogen (Study 1) and as a cocarcinogen (Study 2) when administered in combination with the known environmental carcinogen benzo[a]pyrene. Preparations of 1-nitropyrene and benzo[a]pyrene adsorbed onto an equal mass of carbon carrier particles (Stokes diameter 2 to 5 microns, greater than 70 percent) were used for the intratracheal administration. Evaluation of 1-nitropyrene as a complete carcinogen involved exposing male Syrian golden hamsters to 1 or 2 mg of 1-nitropyrene either once or twice each week. A once-per-week instillation of 2 mg of benzo[a]pyrene served as a positive control. Two groups of animals received sterile saline only (saline controls) or carbon particles suspended in saline (particle controls). In addition, a group of untreated hamsters served as shelf controls. Evaluation of 1-nitropyrene as a cocarcinogen involved treating animals once each week with either 1 or 2 mg of 1-nitropyrene with or without concomitant exposure to 0.25 mg of benzo[a]pyrene. The studies were terminated after 92 weeks of treatment. In both studies, hamsters receiving 1-nitropyrene showed a dose-related decrease in survival and body-weight gain. In general, animals in Study 2 showed better survival than those in Study 1. A high intercurrent mortality was observed in the control groups of Study 1. In order to adjust for intercurrent mortality, tumor incidences were analyzed after modeling (using Cox regression) the effect of treatment in all animals for the period they were alive. A broad spectrum of neoplastic and nonneoplastic lesions was observed in the lungs and tracheas of all hamsters except shelf controls. Because of the histologic complexity of these lesions, the slides were coded, and the tissues were evaluated by an unbiased pathologist. The tumor types included papillomas, adenomas, adenocarcinomas, and squamous cell carcinomas, the latter being the most prevalent type in benzo[a]pyrene-treated animals. In view of the low incidence of tumors in 1-nitropyrene-treated hamsters, the tumor incidences in various experimental groups were compared regardless of the tumor type, location, and multiplicity. A small, but significant, increase in tumor incidence, with a dose-response trend, was observed only in Study 2 hamsters receiving 1-nitropyrene once weekly. In contrast, treatment with benzo[a]pyrene adsorbed onto carbon particles induced benign and malignant tumors virtually in all animals that survived more than 50 weeks of treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Discriminant function analysis: a case study of some socioeconomic constraints on child nutrition

Discriminant function analysis was used to understand the combination of socioeconomic variables in various forms of malnutrition in preschool children. Data available (1976) from two sets viz., 4000 children of rural and urban areas of Hyderabad (in south India) and 215 children of urban and rural areas of Jaipur (in north India) were used for the study. The prevalence rates of various forms of malnutrition in children were different by variations in socioeconomic status and sex (P less than 0.05). Discriminant function analysis of all socioeconomic indicators showed that educational levels and occupational status of parents and percaput income were most important for differentiation of children who were normals and undernourished. Occupational status of the father and the child's calorie intake or duration of lactation improved the differentiation of normals from those who were under-nourished. Higher prevalence of malnutrition in female children than in the male children was found due to variations in per capita income and levels of maternal education. Closely associated best set of factors could be traced using the discriminant function analysis.

Lovastatin treatment of hypercholesterolemia in renal transplant recipients

The treatment of hypercholesterolemia in renal transplant recipients has been problematic. In the present double-blind study, 11 patients were treated with diet for at least 4 weeks. They were then randomized to placebo or the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, lovastatin (20 mg/day) for 6 weeks, followed by crossover to an additional 6 weeks of lovastatin or placebo. All patients had stable allograft function 8.4 +/- 1.2 years (mean +/- SEM) after transplantation, and received low-dose prednisone and azathioprine immunosuppression. Compared with diet alone, lovastatin caused a 21% reduction in total cholesterol from 307 +/- 14 mg/dL to 244 +/- 13 mg/dL (P less than 0.05). Lovastatin reduced LDL cholesterol 28% from 214 +/- 12 mg/dL to 155 +/- 11 mg/dL (P less than 0.05). Trends toward favorable changes in HDL cholesterol, serum triglycerides, and apolipoproteins were not statistically significant. Liver enzymes, creatine phosphokinase, and renal function remained stable. With lovastatin there was a 27% increase in the WBC (from 6220 +/- 530 cells/mm3 to 7780 +/- 510 cells/mm3, P less than 0.05) that was attributable to a 45% increase in neutrophils (P less than 0.05). This effect of lovastatin, possibly the result of reduced azathioprine bone marrow suppression, could have important implications for immunosuppressive therapy in this patient population. Altogether, these results suggest that lovastatin may be a safe and effective treatment for hypercholesterolemia in renal transplant recipients receiving conventional immunosuppression.

Modulatory effects of snuff, retinoic acid, and beta-carotene on DMBA-induced hamster cheek pouch carcinogenesis in relation to keratin expression

The hamster cheek pouch (HCP) serves as an excellent model system not only for the studies on initiation and promotion but also for the modulation of experimental oral carcinogenesis. In our studies, HCPs treated with 7,12-dimethylbenz[a]anthracene (DMBA) showed both cheek pouch and stomach papillomas. Utilizing this model system, we tested and compared the modulatory effects of snuff, retinoic acid, and beta-carotene on the incidence of tumors and the keratin expression pattern. HCPs treated with snuff, either alone or in combination with DMBA, resulted in stomach papillomas. HCPs treated with snuff showed no cheek pouch tumors, and those treated with snuff and DMBA showed only 10-15% tumor incidence. Both beta-carotene and retinoic acid showed a total inhibition of DMBA-induced carcinogenesis in the HCP as well as in the stomach. The keratin expression pattern showed alterations depending on the experimental conditions.

Interspecies analysis of the chemopreventive efficacy of dietary alpha-difluoromethylornithine

The anticarcinogenic efficacy of the polyamine biosynthesis inhibitor, alpha-difluoromethylornithine (DFMO), was assessed in three rodent models of human epithelial cancer. In DMBA-induced female, Sprague-Dawley rats, DMFO treatment (3.2 or 6.4 g/kg diet) for 180 days significantly inhibited mammary carcinogenesis and reduced tumor-related intercurrent mortality compared to untreated controls. In male, C57BL/6x DBA/2F1 mice induced with N-butyl-N(4-hydroxybutyl)nitrosamine (OH-BBN), DFMO treatment (2 or 4 g/kg diet) concurrent with the period of carcinogen administration significantly reduced the incidence and severity of urinary bladder carcinomas. In methylnitrosourea (MNU)-induced male Syrian golden hamsters, DFMO (3.2 g/kg diet) numerically reduced the incidence and size of tracheal carcinoma relative to untreated controls. DFMO-mediated toxicity was not evident in any of the animals on study, although a slight reduction in mean body weight gain was evident in rats and mice.

Influence of cadaver donor age on posttransplant renal function and graft outcome

To assess the impact of cadaver donor age on posttransplant renal function and graft survival, we analyzed our clinical results in 17 recipients of younger donor kidneys (less than 10 years) and 48 recipients of older donor kidneys (greater than 50 years) and compared them with a control group of 598 patients who received kidneys from donors between 11 and 50 years of age. The 3 groups were comparable with respect to recipient age, duration of dialysis, prior transfusions, previous transplants, cold ischemia time, HLA AB mismatches, cytotoxic antibody profile, posttransplant ATN, and prophylactic ALG treatment. The cumulative patient survival at 1, 2, and 3 years was not significantly different among the 3 groups, but the graft survival in recipients of older donor kidneys was significantly lower than the control (71% vs. 62% at 2 years, P = .09 and 66% vs. 55% at 3 years, P = .0003. The short-term renal function assessed at 1 month posttransplant was significantly lower in the older donor group compared with the control (creatinine clearance 45 mL/min vs. 59 mL/min, P = .0003). Likewise, the long-term renal function assessed at the last follow-up was also lower in the older donor group than the control (creatinine clearance 40 mL/min vs. 49 mL/min, P = .07). There were no significant differences in graft survival or short- or long-term renal function between the younger donor group and the control group. These observations suggest that transplantation of a kidney from an older cadaver donor is associated with an inferior posttransplant outcome. The practical decision whether or not to use an older donor kidney should be individualized taking this as well as other factors into account.

Polyvalent immune globulin and cytomegalovirus infection after renal transplantation

To determine whether polyvalent, immune globulin (IgG) prevents cytomegalovirus (CMV) infection after cadaver renal transplantation, 28 patients were randomly allocated to receive 12 weekly infusions of 500 mg/kg of IgG (n = 15) or no treatment (n = 13). Both groups were similar with respect to age, sex, antigen mismatches, number of diabetics, and pretransplant donor/recipient CMV antibody titers. Moderately severe CMV infections occurred in 10 (77%) of 13 control subjects compared with 8 (53%) of 15 IgG-treated patients (not significant). Among those who developed CMV infections, prophylactic IgG had no effect on the severity or duration of fever, leukopenia, or hepatic enzyme elevations. Since none of the IgG-treated patients or control subjects in this study developed life-threatening CMV complications, a beneficial effect of prophylactic IgG in the small number of patients at risk for more severe CMV infections could not be excluded. However, this investigation suggests that the routine, prophylactic administration of polyvalent IgG, to prevent or to ameliorate CMV infection in unselected cadaver renal transplant recipients, is not warranted.

Sequential analysis of experimental oral carcinogenesis in hamster cheek pouch using 9,10-dimethyl-1-2-benzanthracene

The utility of hamster cheek pouch model for studies on oral carcinogenesis has been explored using 9,10-dimethyl-1-2-benzanthracene as a carcinogen. Based on the morphological, histopathological and electron microscopic observations the hamster cheek pouch carcinogenesis can be separated into different stages starting from the normal to the fully grown carcinomas. This system is reliable, precise, consistent and can be used for the evaluation of different agents for initiating or promoting effects and as well as for the studies on mechanism of oral carcinogenesis.

Timing of first birth and second birth spacing in Canada

In Canadian society the influence of first birth timing on the subsequent birth interval has been eroded over time, as shown by the Canadian Fertility Survey of 1984. The influence of first birth timing is significant for second births among women married during the baby boom period, but not for those married thereafter. Religiosity, marital status, and place of residence are significant factors in second birth timing in Canada.

Use of body mass index for assessing the growth status of infants

Growth status of infants measured by weight and height was assessed from birth to 12 months in a randomly selected community from the urban slums of Hyderabad City. Mean birth weight was 2.82 kg. Weight/height indicator of body mass index (BMI) showed a progressive increase till 4th month, followed by more or less a constant figure with a mean value of 1.50 in longitudinal, semi-longitudinal and cross sectional data till one year. Critical limit for BMI at birth for given weight of 2.5 kg was 1.20 and subsequently increased to 1.35. BMI was well correlated with weight and weight for height (%) and least correlated with height. Children with height of 90% or above and birth weight of above 2.5 kg were observed with better growth and better maintenance of weight for height (%) and BMI till 6 months.

Determination of length of human upper limb long bones from their fragments

It is impossible to measure directly the length of fragmentary or broken long bones. It is in order to calculate the height (stature) of the individual, using magnification factors. An attempt has been made to devise a method of calculating the length from such fragments for the three long bones of the upper limb.

Zero-order release formulation of oxprenolol hydrochloride with swelling and erosion control

Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower Cmax, higher values of tmax, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.

Structure of hollow polystyrene microspheres: an SEM study

Hollow polystyrene microspheres have been prepared by a modified interfacial polymer deposition technique. The hollow microspheres were characterized using scanning electron microscopy. The effects of polymer concentration and the quantity of the internal phase material (methanol) used on the microsphere size and their wall thickness were studied. Increase in polymer concentration causes increase in wall thickness while increasing internal phase material increases microsphere size and deforms them from a spherical shape.

Determination of length of human long bones of hands from their fragments

In cases of fragment/broken long bones, it becomes difficult to measure the length of bones for the purpose of calculation of total height (stature) of the individual with the help of magnification factors. An attempt has been made to devise a method of calculating the bones length from fragments on three long bones of the upper extremity.

Acute graft rejection in the late survivors of renal transplantation. Clinical and histological observations in the second decade

The clinical and histological spectrum of renal allograft rejection occurring in the early posttransplant period is well described, but there is not much information with regard to the nature of graft rejection occurring in the long-term survivors of renal transplantation. In this study, we analyzed the incidence, clinical and histological data, and outcome of graft rejection in 69 patients who survived with a functioning kidney for 10 years or longer. In this second decade, during a mean follow-up of 3 years (0.1-9.7 years), 15 patients (22%) developed 20 late rejections. Two of them received living-donor transplants and 13 received cadaver kidneys. Only 8 of these rejections (40%) were associated with abnormal clinical findings; the other 12 (60%) were asymptomatic and were detected on the basis of an unexplained deterioration in graft function. The diagnosis was made on clinical grounds in 10 cases and the other 10 were confirmed by renal histology: acute cellular rejection 1, acute cellular rejection superimposed on chronic rejection 4, and chronic rejection only 5. Thirteen acute rejections in 8 patients were treated with high-dose steroids. Of these, 6 (46%) responded fully, 4 (31%) responded partially, and 3 (23%) did not respond. Seven patients with chronic rejection were not treated. Of these, 5 have returned to dialysis within a mean period of 8 months and one patient died of hepatic failure. Our data suggest that acute reversible graft rejections can occur even after 10 years following renal transplantation. It is therefore essential to continue the maintenance immunosuppressive therapy and monitor the clinical and renal functional data at regular intervals in long-term survivors of renal transplantation.

Effects of tobacco-specific nitrosamines and snuff extract on cell proliferation and activities of ornithine decarboxylase and aryl hydrocarbon hydroxylase in mouse tongue primary epithelial cell cultures

Tobacco and its related compounds, including snuff, have been implicated in oral cancers. Tobacco-specific nitrosamines have been shown to be the causative agents present in tobacco and its related compounds. Both, N-nitrosonornicotine (NNN) and its butanone derivative (NNK) are carcinogenic in animals. In our in vitro studies using embryonic mouse tongue epithelial cells, NNN is linked to an increase in [3H]dT uptake along with a concomitant increase in ornithine decarboxylase and aryl hydrocarbon hydroxylase activities. NNK, the more potent compared to NNN, causes a further increase in [3H]dT uptake, cell count and ornithine decarboxylase activity. However, aryl hydrocarbon hydroxylase behaves differently in cultures treated with NNK compared to those treated with NNN. Snuff extract has an overall inhibitory effect on cell count, [3H]dT uptake, and ornithine decarboxylase and aryl hydrocarbon hydroxylase activities when administered either alone or in combination with NNN and NNK. How the inhibitory effect of snuff in the presence of tobacco-specific nitrosamines is involved in oral carcinogenesis should be further investigated.

Long-term cyclosporine pharmacokinetic changes in renal transplant recipients: effects of binding and metabolism

Sequential changes in the pharmacokinetics of cyclosporine (CsA) and metabolites M1, M17, and M21 were determined, 1, 3, and 12 weeks after initiation of CsA therapy in 21 renal transplant recipients. Concentrations of CsA and its metabolites were measured by HPLC. The dose-adjusted AUC (AUCSS tau) and 24-hour trough (C24trough) level of CsA and the metabolites increased significantly during the study period. However, there was no change in the AUCSS tau ratio of each of the metabolites to that of CsA, suggesting that CsA metabolism did not change. However, the factors that alter the binding and distribution of CsA (i.e., hematocrit, plasma proteins, and lipoproteins) showed a significant rise during the study period, and the rise correlated well with the observed changes in AUCSS tau and C24trough. Thus alterations in the distribution and binding of CsA and its metabolites in blood, rather than reduction in the metabolism of CsA, may explain changes in CsA pharmacokinetics over time.

Gangrene of the lung

Case histories of four patients with gangrene of the lung are presented. All of these patients had characteristic radiographic features of the disease. Two patients had resection and survived. One patient who spontaneously coughed up necrotic tissue via the bronchus survived. One patient who died of an acute myocardial infarction was found at autopsy to have the characteristic pathologic findings of gangrene of the lung.

Enhanced expression of tonofilament bundles during hamster cheek pouch carcinogenesis is associated with tumour growth and the loss of high molecular weight keratins

The altered pattern in the expression of keratin proteins as a function of tumour progression was studied in the hamster cheek pouch and compared the changes with electron microscopic observations using DMBA as a carcinogen. In the case of hyperplasia and well developed tumours a conspicuous loss of 67 K and an increase in 46 K was observed compared to the controls. The increased expression of low molecular weight keratins during tumour growth is well supported by the enhanced expression of tonofilament bundles, electron microscopically. This study suggests a triangular relationship between the presence of low molecular weight keratins-enhanced expression of tonofilament bundles and the undifferentiated nature of the oral tumours.

The relationship between cyclosporine pharmacokinetic parameters and subsequent acute rejection in renal transplant recipients

The best approach to determining the optimal dose of cyclosporine in renal transplant recipients is unclear. In this prospective investigation, CsA pharmacokinetic studies were performed in 45 patients 1, 4, and 12 weeks after the initiation of CsA. Data from 104 studies were then combined to analyze the relationship between CsA kinetic parameters and posttransplant clinical events. Random trough levels, used in the day-to-day adjustment of CsA dose, were examined separately in 19 of the 45 study patients. All CsA levels were measured with high-performance liquid chromatography. Results showed: (1) trough CsA levels, obtained by random sampling, or from the kinetic studies, correlated poorly with dose; however, there was a good correlation between CsA dose and maximum concentration (Cmax, r = .39, P less than .001), area under the concentration-time curve (AUC, r = .45, P less than .001), and terminal elimination half-life (r = .43, P less than .001); (2) several pharmacokinetic parameters correlated with subsequent rejection episodes; patients with acute rejection within 2 or 4 weeks after study had 15-31% lower Cmax (P less than .05) and 13-19% lower AUC (P less than .05) compared to those who were rejection-free; and (3) levels of blood constituents known to bind CsA also correlated with rejection, and this correlation was independent of the impact of kinetic parameters on rejection. Altogether, these results suggested that a limited number of CsA pharmacokinetic studies may be more useful than multiple, random trough levels in monitoring CsA therapy.

Decreased progesterone binding and attenuated progesterone action in cultured human breast carcinoma cells treated with epidermal growth factor

Specific progesterone binding by cultured human breast carcinoma T47D, MCF-7, and ZR75-1 cells was decreased 25-40% by epidermal growth factor (EGF), with a 50% effective dose of 0.1 nM EGF. Studies with the soluble and particulate fractions prepared after homogenization of T47D cells grown in glass roller bottles revealed equivalent EGF-induced decreases in progesterone binding to receptors in both fractions. Equilibrium progesterone binding studies with these soluble and particulate fractions revealed that EGF decreased the receptor number, but had no effect on affinity. With cells grown adherent to plastic dishes, EGF treatment induced a greater decrease in binding to receptors recovered in the particulate fraction, than to receptors recovered in the soluble fraction. The decrease in progesterone binding induced by 20 nM EGF was maximal after 2 min of cellular EGF treatment for receptors recovered in the soluble fraction, but was only half-maximal after 15 min for receptors recovered in the particulate fraction. Decreased progesterone binding persisted for at least 8 days in cells cultured with 1 nM EGF. Either insulin or EGF stimulated T47D cell proliferation by two- to threefold with a 50% effective dose of 100 nM for insulin and 0.1 nM for EGF. The progestin, R5020, decreased T47D cell growth by 30% with a 50% effective dose of 1 nM. Either EGF or insulin antagonized the inhibitory effect of R5020 on cell reproduction, but progestins did not antagonize the growth stimulatory response of cells to EGF. Progestins increased the number of EGF receptors within 12 h of their addition to T47D cells, but this response was lost after 6 days. These data show that EGF or progesterone can regulate the receptor number of the other, but for cell reproduction, the effect of EGF is dominant over that of progestins.