Composting coffee wastes, a potential source of ochratoxigenic fungi and ochratoxin A contamination

Ochratoxin A (OTA) has been extensively documented as a global contaminant of a wide variety of food commodities including the green coffee bean, but there is no clear information available on the spread of Aspergillus ochraceus in the coffee production chain. In this study, the growth of A. ochraceus and the fate of OTA during composting of solid coffee wastes, i.e. pulp and husk, were investigated. A trial was set up with pulp and husk alone or in combination, naturally and artificially contaminated with A. ochraceus. OTA was detected at levels up to 2.6 and 6.2 ng/g in naturally and artificially contaminated pulp, respectively. At the end of the composting process, 8.4 and 14.2 ng OTA per g were measured in naturally and artificially contaminated husk, respectively. Throughout the composting process, A. ochraceus counts did not show any clear increasing or decreasing trend.

Pediatric epidural tumors of the spine--experience of a decade from the Kashmir Valley

We present our experience after analyzing retrospectively the clinicopathological characteristics, surgical approaches, immediate and long-term postoperative complications and survival outcome of pediatric spinal epidural tumors treated over a period of 10 years from 2000 to 2009 in a tertiary-care hospital. Our study included benign and malignant tumors. The majority of our patients were boys (14:8). The duration of symptoms was longer in benign lesions. Non-Hodgkin's lymphoma was the commonest malignant tumor and aneurysmal bone cyst was the commonest benign tumor. The mean duration of follow-up was 19 months (range 3-48 months). Most of the patients improved in their neurological grade after surgery; however, the degree of excision had no bearing on the length of survival for malignant lesions.

Immunoglobulin G4-associated cholangitis mimicking cholangiocarcinoma in a young boy

Autoimmune pancreatitis is a rare form of chronic pancreatitis, which commonly mimics pancreatic carcinoma. Immunoglobulin G4-associated cholangitis (IAC) is a rare type of autoimmune pancreatitis associated with bile duct involvement, which can present with or without pancreatic involvement. Usually, the bile duct involvement is in the form of multiple intra-and extra-hepatic strictures mimicking primary sclerosing cholangitis. Rarely, there can be an isolated stricture which mimics cholangiocarcinoma. Differentiating these from cholangiocarcinoma, though extremely difficult, is of critical importance since it can be treated without surgical intervention. Most cases with rare presentation mimicking cholangiocarcinoma have been reported in elderly patients. We present one such rare presentation of autoimmune pancreatitis in a young 13-year-old patient in whom hepaticojejunostomy was done for a hilar stricture, which later turned out to be related to IAC. To our knowledge this is the first reported case of its kind from India.

Fermentor temperature as a tool for control of high-density perfusion cultures of mammalian cells

Temperature is a key environmental variable whose potential in animal cell fermentor optimization is not yet fully utilized. The scarce literature data suggests that reduced fermentor temperature results in an improved viability and shear resistance, higher cell density and titer in batch cultures, and reduction in glucose/lactate metabolism. Due to the arrest of the cells in the G1 phase, the specific growth rate was found to decrease at temperatures below 37.0 degrees C. The response of the specific production rate was cell line dependent: in some cases it increased 2-to-3-fold, but decreased in other cases. The controlable slowdown of cell metabolism at lower temperature can be used in optimization of perfusion mammalian cell cultures with several potential advantages, including higher cell density in oxygen limited reactors, lower perfusion rate, improved product quality, simplified pH control, and others. To evaluate this strategy, a series of long-term experiments in 15 L perfusion bioreactors culturing recombinant hamster cells at 20.0 x 10(6) cells/mL were conducted. The temperature was changed over a range of set points, and maintained at each of these for a long period of time. Steady state process data was collected and analyzed. The effect of temperature on the following characteristics of the perfusion process was studied: cell growth, glucose/lactate metabolism, glutamine/ammonia metabolism, cell respiration, cell density at constant oxygen transfer rate, proteolytic activity, and product quality (glycosylation and molecule fragmentation). The results suggest that temperature is a variable with a significant potential in optimization of perfusion cultures. Properly selected temperature set point will contribute to the overall improvement of process performance. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 328-338, 1997.

Twin to twin transfusion syndrome

Twin to twin transfusion syndrome (TTTS) is a specific condition complicating 10-15% of monochorionic multiple pregnancy. Intertwin vascular anastomoses and transfusion is a normal event. Syndrome develops when blood flow is unbalanced. Recent studies suggest a paucity of bi-directional superficial anastomoses failing to compensate for hemodynamic imbalance resulting from unidirectional transfusion along deeper arterio-venous anastomoses. TTTS is associated with high rates of perinatal mortality. Acute and chronic forms exist and severity varies. The donor twin is often smaller, hypovolemic, anemic and develops congestive heart failure. The recipient is usually heavier and polycythemic. Antenatally, second trimester ultrasound usually detects the condition. Serial amnioreduction is the recommended therapy. Postnatally, intertwin haemoglobin and birth weight differences along with pallor in one twin and plethora in the other are helpful in making a diagnosis. Medical care of twins after birth is directed towards problem related to anemia, polycythemia and hydrops. Review of the syndrome is presented with an illustrative case.

Pharmacotherapy for meconium aspiration

In this article we have attempted to review the current pharmacological treatment options for infants with meconium aspiration syndrome with or without persistent pulmonary hypertension. These treatments include ventilatory support, surfactant treatment and inhaled nitric oxide (INO), in addition to older and newer pharmacological treatments. These include sedatives, muscle relaxants, alkali infusion, antibiotics and the newer vasodilators. Many aspects of treatment, including ventilatory care, surfactant treatment and the use of INO, are reviewed in great detail in this issue. On the other hand, many newer pharmacological modalities of treatment described here have not been evaluated with randomized control trials. We have given an overview of these emerging therapies.

Stent graft exclusion of pseudo-aneurysm arising from PTFE hemodialysis graft after recurrence following ultrasound guided thrombin injection

There are various non-invasive or minimally invasive techniques for management of pseudoaneurysms including ultrasound guided compression, ultrasound guided thrombin injection and covered stent placement. We report a case where a covered stent graft was successfully used for the treatment of a pseudoaneurysm directly arising from a PTFE graft which recurred 3 months following treatment with ultrasound guided thrombin injection.

Endovascular repair of a ruptured mycotic aneurysm of the common iliac artery

This report describes the case of a ruptured mycotic aneurysm of the left common iliac artery, successfully treated with endovascular stent-grafting. A 64-year-old woman underwent diagnostic coronary angiography complicated by an infected hematoma of the left groin. Seven days later, she developed methicillin-resistant Staphylococcus aureus septicemia and CT scan evidence of perivascular inflammation around the left common iliac artery. This was followed by rupture of a mycotic aneurysm of the left common iliac artery. The lesion was successfully treated with a stent-graft and prolonged antibiotic therapy, and the patient remains free of infection 10 months later. Accumulating evidence suggests that endovascular repair can be used safely for the repair of ruptured infected aneurysms.

Effect of pioglitazone therapy in lean type 1 diabetes mellitus

OBJECTIVE

The beneficial effects of metformin in peripubertal adolescents and rosiglitazone in overweight type 1 diabetic subjects, though modest have been demonstrated. This study was designed to analyze the effect of pioglitazone as an adjunctive therapy in post-pubertal lean T1DM.

PATIENTS AND METHODS

Sixty type 1 diabetic subjects with duration of illness of a year or more with body mass index between 18 and 24.9 kg/m(2) were randomly assigned to receive either 30 mg pioglitazone or placebo once daily for 6 months. The study was double-blinded placebo controlled with 30 subjects in each group, matched for age, sex, anthropometric and metabolic parameters. At the end of the study period, plasma glucose levels, HbA(1c), lipids and insulin requirement were compared between the two groups.

RESULTS

A significant improvement in post-prandial plasma glucose (PPPG) levels (9.1+/-1.7 and 8.4+/-1.3 mmol/L, p=0.002) and HbA(1c) (7.08+/-0.48 and 6.86+/-0.45%, p=0.001) were observed in the pioglitazone treated group, but not in the placebo treated group (8.3+/-1.8 and 7.8+/-1.8 mmol/L, p=0.06 and HbA(1c) 7.3+/-0.37 and 7.24+/-0.33%, p=0.74, respectively). However, the mean decrease in PPPG and HbA(1c) levels between groups corrected for baseline values at the end of study was significant only for the later (HbA(1c) -0.22+/-0.29 and -0.06+/-0.49, p=0.03), while for the former, it got attenuated (PPPG -0.69+/-1.1 and -0.48+/-1.36, p=0.68). There was no alteration in body weight, body mass index, insulin requirement, blood pressure and lipid profile in both the groups at the end of the study.

CONCLUSION

Pioglitazone is modestly effective adjunct to insulin therapy in lean type 1 diabetic subjects. It improves post-prandial glucose levels and HbA(1c) without alterations in body weight and insulin requirement.

Accidental blood exposure: risk and prevention in interventional radiology

There is a growing concern about the transmission of bloodborne pathogens during medical procedures among health care workers and patients. Over the last three decades, radiological services have undergone many changes with the introduction of new modalities. One of these new disciplines is interventional radiology (IR) which deals with procedures such as arteriography, image-guided biopsies, intravascular catheter insertions, angioplasty and stent placements. Despite these developments, the potential for accidental blood exposure and exposure to other infectious material continues to exist. Therefore, it is important for all radiologists who perform invasive procedures to observe specific recommendations for infection control. In this review, we look at the different policies for protection and universal standards on infection control.

Precocious pseudopuberty with testicular enlargement

Gonadotropins independent precocious puberty (GIPP) in male is characterized by early appearance of sexual hairs and phallic growth but without testicular enlargement. We report a case of GIPP with testicular enlargement who was diagnosed to have testotoxicosis and successfully managed with spironolactone.

Ichthyosis follicularis, alopecia and photophobia (IFAP) syndrome treated with acitretin

We describe a 3-year-old male patient with the ichthyosis follicularis, alopecia and photophobia (IFAP) syndrome, who developed cutaneous and ocular involvement in infancy. In addition, he had growth retardation and borderline intelligence; no other systemic involvement was found on detailed investigation. A moderate response to acitretin therapy (1 mg/kg) administered for 6 months was observed, with improvement in cutaneous features and corneal erosions and no change in alopecia or photophobia.

Diminished lung function, RSV infection, and respiratory morbidity in prematurely born infants

BACKGROUND

Diminished lung function appears to be a risk factor for respiratory syncytial virus (RSV) infection/bronchiolitis in term born infants.

AIMS

To determine if diminished lung function prior to neonatal unit discharge was associated with subsequent symptomatic RSV lower respiratory tract infection (LRTI) and respiratory morbidity in prematurely born infants.

METHODS

Of 39 infants in a tertiary neonatal intensive care unit (median gestational age 28 weeks, range 23-31), 20 had bronchopulmonary dysplasia. Lung function (compliance and resistance of the respiratory system (C(rs) and R(rs)) and functional residual capacity (FRC)) was measured on the neonatal unit at 36 weeks postmenstrual age (PMA). Following neonatal unit discharge, nasopharyngeal aspirates were obtained on every occasion, at home or in hospital, an infant had an LRTI. RSV was identified by immunofluorescence and/or culture.

RESULTS

The 15 infants who suffered a symptomatic RSV LRTI had a higher mean R(rs) and suffered more wheeze at follow up than the rest of the cohort. Regression analysis showed that a high R(rs) was significantly associated with a symptomatic RSV LRTI; significant factors for cough were a high R(rs) and a symptomatic RSV LRTI, and for wheeze were a high R(rs).

CONCLUSION

Prematurely born infants, who had a symptomatic RSV LRTI and/or respiratory morbidity at follow up, had worse lung function prior to neonatal unit discharge.

Characterization of serine/cysteine protease inhibitor α1-antitripsin from meconium-instilled rabbit lungs

We have recently purified from meconium-instilled rabbit lungs a novel serine proteinase inhibitor, with an apparent molecular mass of 50 kDa, which we assign to be alpha1-antitripsin. We hypothesize that serpin may attenuate pulmonary inflammation and improve surfactant function after meconium aspiration. Alpha1-antitripsin is a member of the proteinase inhibitor (serpin) superfamily and inhibitor of neutrophil elastase, and it can be identified as a member of the family by its amino acid sequence due to the high degree of conserved residues. Alpha1-antitripsin is synthesized by epithelial cells, macrophages, monocytes, and neutrophils. Deficiency in alpha1-antitripsin leads to exposure of lungs to uncontrolled proteolytic attack from neutrophil elastase or other damaging factors culminating in lung destruction and cell apoptosis. We hypothesize that accumulation of alpha1-antitripsin in the lungs serves as a predisposed protection against meconium-induced lung injury. In this paper, we show how this knowledge can lead to the development of novel therapeutic approaches for treatment of MAS.

GSK-3beta inhibition reverses axonal transport defects and behavioural phenotypes in Drosophila

The tauopathies are a group of disorders characterised by aggregation of the microtubule-associated protein tau and include Alzheimer's disease (AD) and the fronto-temporal dementias (FTD). We have used Drosophila to analyse how tau abnormalities cause neurodegeneration. By selectively co-expressing wild-type human tau (0N3R isoform) and a GFP vesicle marker in motorneurons, we examined the consequences of tau overexpression on axonal transport in vivo. The results show that overexpression of tau disrupts axonal transport causing vesicle aggregation and this is associated with loss of locomotor function. All these effects occur without neuron death. Co-expression of constitutively active glycogen-synthase kinase-3beta (GSK-3beta) enhances and two GSK-3beta inhibitors, lithium and AR-A014418, reverse both the axon transport and locomotor phenotypes, suggesting that the pathological effects of tau are phosphorylation dependent. These data show that tau abnormalities significantly disrupt neuronal function, in a phosphorylation-dependent manner, before the classical pathological hallmarks are evident and also suggest that the inhibition of GSK-3beta might have potential therapeutic benefits in tauopathies.

Cocaine permeability and metabolism in colonic T-84 epithelial cell line

We studied the uptake, transport and metabolism of cocaine in human intestine using the colonic T-84 monolayers as a model. T-84 cells were grown in DMEM/Ham's F-12 medium containing 6% newborn calf serum at 37 degrees C on 1.0 microm collagen inserts. The cells develop into a polarized monolayer with the apical surface facing the upper chamber and the basolateral surface facing the lower. The monolayers develop a transepithelial resistance of > or = 600 ohms cm2 in 7 days. Varying concentrations of cocaine HCI was added in a serum free medium to the luminal side only, and after 30 min and 60 min samples from the luminal and serosal aspect were removed for analysis. Cocaine and its metabolites were measured by GC/MS. Cocaine transport across T-84 monolayers increased linearly with increasing concentration of cocaine, with no significant difference between 30 min and 60 min of exposure. Transepithelial resistance did not change even at 800 ng of cocaine suggesting no effect on monolayer viability. The metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME) but not norcocaine were detected in both luminal and serosal side. The concentrations of BE and EME in the luminal side were significantly higher than in the serosal. Combined recovery of cocaine, BE and EME from luminal and serosal sides were 52 - 80% of total added cocaine. While fresh medium did not metabolize cocaine, media previously exposed to the monolayer (cell-free medium) caused a significant breakdown into BE and EME, suggesting that esterases may be released into the medium. These results indicate transfer of cocaine across this model of intestinal epithelial cell line is by simple diffusion and is concentration dependent. These studies imply that cocaine in swallowed amniotic fluid can be absorbed by the fetal gastrointestinal tract.

Effect of pH on stability of anthrax lethal factor: correlation between denaturation and activity

Anthrax is caused by Gram positive bacterium Bacillus anthracis. Pathogenesis is result of production of three protein components, protective antigen (PA), lethal factor (LF), and edema factor (EF). PA in combination with LF (lethal toxin) is lethal to animals, while PA in combination with EF (edema toxin), causes edema. PA, LF, and EF are very thermolabile. Differential scanning calorimetry (DSC) was used to unravel the energetics of LF denaturation as a function of pH ranging from 7.8 to 5.5. Transition temperature (T(m)) of LF was found to be approximately equal to 42 degrees C and onset of denaturation occurs at approximately equal to 30 degrees C. The ratio of calorimetric to van't Hoff's enthalpy was nearly equal to unity at pH 7.0, indicative of presence of single structural domain in LF at pH 7.0, unlike PA which has been structurally observed to consist of 4 domains. It was found by cytotoxicity studies using J774A.1 macrophage like cells that LF was most stable at pH approximately 6.5. This paper reports for the first time the denaturation of LF at different pH values at 37 degrees C and tries to establish a correlation between denaturation and loss of LF activity at different pH values.

Regulation of metallothionein II messenger ribonucleic acid measures exogenous estrogen receptor-beta activity in SAOS-2 and LNCaPLN3 cells

Estrogen receptor-beta (ERbeta) is a recently discovered member of the steroid hormone superfamily. Because its distribution is distinct from that of the classical estrogen receptor, and it is expressed in several nonclassical estrogen target tissues (e.g. prostate and bladder), its role in mediating the action of estrogen is unclear. One approach to elucidating the function of this receptor is to identify genes that it regulates. Using differential display, we profiled the messenger RNAs regulated by 17beta-estradiol in SAOS-2 and LNCaPLN3 cells overexpressing ERbeta. Follow-up studies used cells expressing either ERalpha or ERbeta. One gene, metallothionein II, was regulated by both receptor subtypes in LNCaPLN3 cells, but only by ERbeta in SAOS-2 cells. Because cycloheximide blocks this response, induction is probably mediated through regulation of at least one other protein. Identification of endogenous genes that are regulated differentially by ERalpha and ERbeta will be valuable tools in elucidating the function of ERbeta and the mechanisms by which these two receptors regulate transcription.

Cell death and lung cell histology in meconium aspirated newborn rabbit lung

Meconium aspiration syndrome (MAS) is a major cause of newborn mortality and morbidity. In this study we investigated the inflammatory responses and morphological changes in the newborn lung to debris-free meconium instillation. We developed a model for studies of MAS using 2-week-old rabbit pups. Cell death was assessed by DNA staining and detection of DNA fragmentation by in situ end labeling. Cell death was seen in association with an increase of inflammatory cytokines levels, studied by ELISA. Necrotic cells were detected by staining of lavage cells with ethidium bromide and 4',6'-diamino-2'-phenylidon. Meconium instillation resulted selectively in loss of airway and alveolar epithelial cells followed by cell death, which increased with time. Necrotic cells looked smaller and damaged with maximal counts at 24 h after instillation.

CONCLUSION

Meconium instillation into lungs caused massive cell death, possibly by apoptosis, and necrosis that may have been activated by the inflammatory cytokine production.

Immune responses to hepatitis C virus structural and nonstructural proteins induced by plasmid DNA immunizations

DNA-based immunizations have been used to elicit cellular immunity to hepatitis C virus (HCV) proteins in mice. Mice were immunized by intramuscular or intradermal injections of plasmid DNA derived from a near-full-length HCV genotype 1b genomic clone (pRC/B2) or individual genomic clones. These immunizations induced cytotoxic T lymphocytes (CTLs), as revealed in standard chromium-release assays that used syngeneic peptide-pulsed or transfected target cells. These assays identified four CTL epitopes within the capsid, E1, and E2 regions of the polyprotein sequence of HCV genotype 1a that were cross-reactive with HCV genotype 1b. Additionally, CTLs derived from mice immunized with either NS3 or NS5 specifically lysed target cells sensitized to either the genotype 1a or 1b gene products. Nucleic acid immunizations also generated humoral immunity to HCV proteins, as detected by anti-HCV reactivity to NS3 and capsid in ELISAs and immunoblot assays.

Characteristics of private medical practice in India: a provider perspective

Supply factors, depicted by input market conditions and government regulations, and demand factors, depicted by financing mechanisms and utilization patterns, are likely to determine the shape and character of private medical practice. The interaction of this complex set of factors will have considerable implications for the cost access and quality of services offered by this sector. Understanding these characteristics from a provider perspective is imperative to influence the behaviour of providers in this sector. This paper describes some of the important characteristics of private medical practice using a case study of an urban district in India, Ahmedabad, and analyzes their implications. Using survey data of 130 private doctors in the allopathic system, the paper describes broad characteristics of private medical practice using parameters such as growth of private practice, patient load and referrals within the sector, payment methods and determinants, patient concerns, and risks associated with private practice. The paper presents views on the prevalence of various undesirable practices in the private medical sector. It also discusses the awareness of providers about selected important regulations. The findings suggest that growing capital intensity due to cost of location, medical equipment and technology, and financial sources of capital investments are some unfavourable environmental factors experienced by private providers. The findings also indicate a high prevalence of various undesirable practices and low awareness of the objectives of important legislation among practicing doctors. Lack of awareness of important and relevant legislation raises serious questions about the implementation of these laws. The paper identifies the strong need for instituting and implementing an effective continuing medical education programme for practicing doctors, and linking it with their registration and continuation of their license to practice. The paper also suggests that cost of health care, access and quality problems will worsen with the growth of the private sector. The public policy response to check some of the undesirable consequences of this growth is critical and should focus on strengthening the existing institutional mechanisms to protect patients, developing and implementing an appropriate regulatory framework and strengthening the public health care delivery system. The study also discusses various other policy implications arising.

A mechanistic analysis of the increase in the thermal stability of proteins in aqueous carboxylic acid salt solutions

The stability of proteins is known to be affected significantly in the presence of high concentration of salts and is highly pH dependent. Extensive studies have been carried out on the stability of proteins in the presence of simple electrolytes and evaluated in terms of preferential interactions and increase in the surface tension of the medium. We have carried out an in-depth study of the effects of a series of carboxylic acid salts: ethylene diamine tetra acetate, butane tetra carboxylate, propane tricarballylate, citrate, succinate, tartarate, malonate, and gluconate on the thermal stability of five different proteins that vary in their physico-chemical properties: RNase A, cytochrome c, trypsin inhibitor, myoglobin, and lysozyme. Surface tension measurements of aqueous solutions of the salts indicate an increase in the surface tension of the medium that is very strongly correlated with the increase in the thermal stability of proteins. There is also a linear correlation of the increase in thermal stability with the number of carboxylic groups in the salt. Thermal stability has been found to increase by as much as 22 C at 1 M concentration of salt. Such a high thermal stability at identical concentrations has not been reported before. The differences in the heat capacities of denaturation, deltaCp for RNase A, deduced from the transition curves obtained in the presence of varying concentrations of GdmCl and that of carboxylic acid salts as a function of pH, indicate that the nature of the solvent medium and its interactions with the two end states of the protein control the thermodynamics of protein denaturation. Among the physico-chemical properties of proteins, there seems to be an interplay of the hydrophobic and electrostatic interactions that lead to an overall stabilizing effect. Increase in surface free energy of the solvent medium upon addition of the carboxylic acid salts appears to be the dominant factor in governing the thermal stability of proteins.

Bile flow and composition in preterm, term and infant baboons

We studied the maturational changes in bile composition, bile flow and choleretic effects of sodium taurocholate and secretin in preterm (160 +/- 2 days, n = 4, group I), term (184 +/- 2 days, n = 4, group II), 7-day postnatal age (n = 5, group III) and 60-day-old (n = 5, group IV) baboons. The canalicular bile flow was determined by 14C-erythritol clearance.

RESULTS

Gall bladder volume increased from group I to group III (0.08 +/- 0.06 to 1.06 +/- 0.93 ml). Bile flow increased significantly from group I to IV (0.13 +/- 0.05 to 0.34 +/- 0.07 microliter/min/g liver weight, p < 0.05). This was associated with significant increases in total bile acid excretion (16 +/- 3.6 to 31 +/- 2.5 mEq/l, p < 0.05). The composition of bile also showed maturational changes with increasing postnatal age. Sodium taurocholate and secretin increased the bile flow significantly in all groups.

CONCLUSION

Data from these studies clearly demonstrate that the bile flow and bile acid excretion is immature in preterm and term baboons when compared to 7- and 60-day-old baboons. The present studies also suggest that baboons can be used as a model to study the postnatal maturation of hepatic excretory function.

Glycine N-methyltransferase is an example of functional diversity. Role as a polycyclic aromatic hydrocarbon-binding receptor

The cytochrome P-4501A1 (CYP1A1) gene is regulated by several trans-acting factors including the 4 S polycyclic aromatic hydrocarbon (PAH)-binding protein, which has recently been identified as glycine N-methyltransferase (GNMT) (Raha, A., Wagner, C., Macdonald, R. G., and Bresnick, E. (1994) J. Biol. Chem. 269, 5750-5756). The role of GNMT as a 4 S PAH-binding protein in mediating the induction of cytochrome P-4501A1 has been investigated further. GNMT cDNA, which was cloned into a pMAMneo vector containing the Rous sarcoma virus promoter and the neomycin resistance gene, was stably transfected into D422 Chinese hamster ovary (CHO) cells. Several positive clones were selected by reverse transcription-polymerase chain reaction and assayed for the expression of recombinant protein. Western blot analysis indicated the expression of significant levels of the 4 S protein in the stably transfected CHO cells (CHO-GNMT). Cytosolic preparations from the CHO-GNMT showed high benzo[a]pyrene (B[a]P) binding but no 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) binding activity when compared with clones transfected with the pMAMneo vector alone (CHO-neo) or the parental CHO cells. Challanging the CHO-GNMT cells with 4 microM B[a]P resulted in elevated levels of CYP1A1 mRNA. Equally effective in inducing CYP1A1 mRNA were benzo[e]pyrene and 3-methylcholanthrene. On the other hand, TCDD did not induce CYP1A1 gene expression in these cells. B[a]P-treated CHO-GNMT, expressing the 4 S protein, also showed CYP1A1 protein by Western blotting and exhibited ethoxyresorufin-O-deethylase activity; neither the CHO-neo or parental CHO cells were positive for any of these measures. No Ah receptor message or protein was detectable in the parental CHO, CHO-neo, or CHO-GNMT cells. Furthermore, no XRE binding activity was observed in TCDD-treated cytosolic preparations or nuclear extracts from CHO-GNMT cells that were treated with TCDD. These studies unequivocally establish that GNMT is a PAH-binding protein that can mediate the induction of CYP1A1 by PAHs such as B[a]P through an Ah receptor-independent pathway.

The homodimeric form of glycine N-methyltransferase acts as a polycyclic aromatic hydrocarbon-binding receptor

In the rat, cytochrome P4501A1 gene expression is thought to be regulated by several trans-acting factors including the 4S polycyclic aromatic hydrocarbon (PAH)-binding protein, which was recently identified as glycine N-methyltransferase [Raha, A., Wagner, C., MacDonald, R. G., and Bresnick, E. (1994) J. Biol. Chem. 268, 5750-5756]. Glycine N-methyltransferase (GNMT) is one of those unique proteins which exhibit diversity in function. Different subunit configurations are involved in its enzymatic role as a methyltransferase and as PAH-binding receptor. Here we report a systematic study of the oligomeric state of GNMT in the presence of benzo[a]pyrene (B[a]P) in vivo and in vitro. We have used chemical cross-linking and denaturing polyacrylamide gel electrophoresis to show that the B[a]P-binding unit of GNMT is a homodimer. We recently reported that phosphorylation is involved in the interaction of B[a]P with the 4S PAH-binding protein [Bhat, R., Weaver, J. A., Wagner, C., Bodwell, J. E., and Bresnick, E. (1996) J. Biol. Chem. 271, 32551-32556]. In the present study, this observation has been amplified by using bacterially expressed GNMT, which was post-translationally modified by a reticulocyte lysate and ATP-generating system. This modification was also accompanied by the formation of homodimers in the presence of B[a]P. These results indicate that post-translational modification is involved in determining the final configuration, i.e., dimeric form, of GNMT which then acts as a PAH-binding receptor.

ATP depletion affects the phosphorylation state, ligand binding, and nuclear transport of the 4 S polycyclic aromatic hydrocarbon-binding protein in rat hepatoma cells

In the rat, cytochrome P4501A1 gene expression is thought to be regulated by several trans-acting factors including the 4 S polycyclic aromatic hydrocarbon (PAH)-binding protein. Phosphorylation and dephosphorylation have been suggested to influence the function of many cytosolic receptors and transcription factors. The ATP level within H4IIE rat hepatoma cells could be depleted by treatment with sodium azide or 2,4-dinitrophenol; restoration of the original ATP levels occurred with addition of glucose to the cell culture. ATP depletion reduced the phosphate content of the 4 S protein by approximately 25-30%, which lowered the binding of benzo[a]pyrene (B[a]P) to the 4 S protein by >60%. This effect could not be reversed by the addition of ATP to the binding reaction mixtures. Alkaline phosphatase treatment of the purified 4 S protein in a cell-free system also reduced the B[a]P binding to the protein. Cells treated with a protein phosphatase inhibitor, okadaic acid, and a protein kinase inhibitor, staurosporin, affected the B[a]P binding of the 4 S protein positively and negatively, respectively. These data suggested that phosphorylation is involved in the interaction of the 4 S protein with the PAH. The nuclear translocation of the predominantly cytosolic binding protein has been investigated after ligand binding. Western blots with the immunopurified 4 S PAH-binding protein from cytosolic and nuclear lysates showed significant differences in the distribution of the 4 S receptor between cytosolic and nuclear compartments in control and ATP-depleted cells. Ligand binding stimulated the movement of the receptor into the nucleus, which was completely blocked by reducing the intracellular ATP concentration. These findings provide new information on the role of ATP and phosphorylation on the interaction of B[a]P with 4 S PAH-binding protein and its nuclear translocation.

Characterization of large, heterogeneous proteins by electrospray ionization-mass spectrometry

Characterization of heterogeneous proteins as large as 150,000 u was performed by a quadrupole mass spectrometer by using electrospray ionization (ESI). We were able to determine not only the molecular weight, but the detailed heterogeneity for the large glycoproteins as well. The successful application was facilitated by the optimization of the instrument in the high mass-to-charge range up to m/z 4000, where the multiply charged envelopes of the 150,000-u glycoproteins were found. For the analysis of clinically important monoclonal antibodies mass spectral data acquired by this method were consistent with the carbohydrate analysis and were useful in resolving the monosaccharide data into glycoform variations. In the case of the characterization of other large, heterogeneous proteins such as elongation factor 3 and bovine serum albumin, the quadrupole ESI mass spectrometer provided adequate mass resolution and high mass measurement accuracy to discern the modification and degradation of the proteins.

Thermostabilization of protective antigen--the binding component of anthrax lethal toxin

Protective antigen (PA) is the binding component of anthrax lethal toxin produced by Bacillus anthracis, and constitutes a major ingredient of the vaccine against anthrax. PA and lethal factor when added together are cytolytic to mouse macrophages and J774G8 macrophage cell line. This in vitro lethal toxicity assay is very useful in understanding the molecular mechanism of action of lethal toxin. Effective utilization of PA is, however, hampered due to its thermolability. On prolonged storage at 37 degrees C, PA was found to lose its activity almost completely. The effect of solvent additives like trehalose, sorbitol, xylitol, sodium citrate and magnesium sulphate on the thermal stabilization of PA was examined. The results indicated an increase in the stability of PA when the incubation at 37 degrees C was carried out in the presence of solvent additives used in the 1-3 M range. Magnesium sulphate helped retain the activity up to 82.7% against the control in which no additive was used, as judged by cytolytic assay using J774G8 macrophage cell line. Trehalose or sodium citrate also showed an appreciable protection of PA activity, while sorbitol or xylitol were not very effective. Competitive binding assay using radiolabeled PA showed that PA had lost capacity of binding to macrophage cells on prolonged incubation at 37 degrees C. Circular dichroism results at 4, 18, and 37 degrees C indicated an increase in secondary structure at 37 degrees C relative to that at 4 or 18 degrees C, supporting the activity data.

Regulating the private health care sector: the case of the Indian Consumer Protection Act

Private medical provision is an important constituent of health care delivery services in India. The quality of care provided by this sector is a critical issue. Professional organizations such as the Medical Council of India and local medical associations have remained ineffective in influencing the behaviour of private providers. The recent decision to bring private medical practice under the Consumer Protection Act (COPRA) 1986 is considered an important step towards regulating the private medical sector. This study surveyed the views of private providers on this legislation. They believe the COPRA will be effective in minimizing malpractice and negligent behaviour, but it does have adverse consequences such as an increase in fees charged by doctors, an increase in the prescription of medicines and diagnostics, an adverse impact on emergency care, etc. The medical associations have also argued that the introduction of COPRA is a step towards expensive, daunting and needless litigation. A number of other concerns have been raised by consumer forums which focus on the lack of standards for private practice, the uncertainty and risks of medicines, the effectiveness of the judiciary system, and the responsibility of proving negligence. How relevant are these concerns? Is the enactment of COPRA really appropriate to the medical sector? The paper argues that while this development is a welcome step, we need to comprehensively look into the various quality concerns. The effective implementation of COPRA presumes certain conditions, the most important being the availability of standards. Besides this, greater involvement of professional organizations is needed to ensure appropriate quality in private practice, since health and medical cases are very different from other goods and services. The paper discusses the results of a mailed survey and interview responses of 130 providers from the city of Ahmedabad, India. The questionnaire study was designed to assess the opinion of providers on various implications of the COPRA. We also analyze the data on cases filed with the Consumer Disputes and Redressal Commission in Gujarat since 1991. Four selected cases filed with the National Commission on Consumers Redressal are discussed in detail to illustrate various issues affecting the implementation of this Act.

Subunit structure of Ca++ dependent soluble goat hepatic lectin: evidence that it has antigenic structural relationship with soluble 14K lectin family

The subunit structure of soluble goat hepatic lectin was studied by determining molecular weight under nondenaturing conditions by gel filtration and denaturing conditions by SDS PAGE. Affinity purified lectin was subjected to HPLC on asahipack column equilibrated with 10 mM Tris-HCl pH 7.5, containing 1 mM CaCl2, 1mM 2-mercaptoethanol and 0.1M NaCl. The lectin was eluted under single peak at retention time of 12 min. corresponding to molecular weight of 38Kd. On SDS-PAGE in the presence and absence of 2-mercaptoethanol protein moved as single band with Rm 0.45, which corresponds to molecular weight of 20 Kd. The results suggest that soluble goat hepatic lectin is a dimmer of identical subunits which are linked together by noncovalent interactions. The interaction of monoclonal antibodies raised against soluble goat hepatic lectin (MGHL/20) with hemagglutinin from different species as sheep, human, rat, bovine and chicken was studied in PBS by solid phase binding assay. MGHL/20 showed 29.89% binding with these lectin. However no binding was found with Ca++ dependent membrane bound lectin. These results indicate that soluble goat hepatic lectin possesses antigenic structural relationship with soluble 14 K lectin family.

Regulation of the private health sector in India

The expansion of the private sector in India has forced the passages of a number of regulations to promote quality of care and protect consumers. This has expanded the role of government in developing and enforcing regulations in three areas of the health sector: drugs, medical practice, and health facilities. These regulations have been promulgated by both national and state governments. Three particular Acts are examined: the Consumer Protection Act, Medical Councils, and the Nursing Home Act. These Acts have provided basic guidelines for regulation of certain aspects of the health sector, but have also created new challenges, as consumers have become more involved in monitoring health service delivery. The challenge for the future will be to ensure the quality and efficiency of health services in both the public and private sectors through these regulatory mechanisms while seeking to promote national health objectives.