Leptin antagonizes the insulin-like growth factor-I augmentation of steroidogenesis in granulosa and theca cells of the human ovary

There is increasing evidence that leptin is a physiological link between obesity and infertility. Although leptin receptors have been demonstrated in human ovaries, there is no information regarding the effects of leptin on cells from developing ovarian follicles. To test the direct effects of leptin on human ovarian cells, granulosa cells (GC) and theca cells were isolated from the ovaries of regularly cycling women. Serum was obtained at the time of surgery, and follicular fluid was aspirated from the follicles before isolation of the ovarian cells. Leptin concentrations were similar in follicular fluid and serum. RT-PCR analysis demonstrated that the long, signaling form of the leptin receptor was expressed in both theca and GC. In cultured GC, leptin had no effect on estradiol production, alone or in the presence of FSH, but caused a concentration-related inhibition of the insulin-like growth factor I (IGF-I) augmentation of FSH-stimulated estradiol production. The effect of leptin was specific, because there was no effect on progesterone production. In cultured theca cells, leptin did not alter androstenedione production, alone or in the presence of LH. Leptin caused a concentration-related inhibition of the IGF-I augmentation of LH-stimulated androstenedione production. These data demonstrate that leptin can directly inhibit IGF-I action in ovarian theca and GC at concentrations commonly present in obese women.

Comparison of two schedules of hepatitis B vaccination in patients with mild, moderate and severe renal failure

Seroconversion rate following hepatitis B vaccination in patients of chronic renal failure (CRF) has been in the range of 10%-82% in various studies. Different approaches have been tried to improve seroconversion rate. We studied two schedule of hepatitis B vaccination, 0,1,2 (Group A) and 0,1,2,6 (Group B) in mild (creatinine 1.5 to 3.0 mg%), moderate (creatinine 3.0 to 6.0 mg%) and severe CRF (creatinine > 6.0 mg%). Between Oct. 93 to Oct. 95, 117 patients with CRF who were negative for HBsAg and anti-HBs were included in the study. Forty micrograms of recombinant vaccine "ENGIREX" (20 micrograms in each deltoid region) was given in both the groups. Number of cases of mild, moderate and severe CRF were 18, 15 and 42 in group A and 12, 13 and 17 in group B, respectively. One month after the last dose of vaccination, anti-HBs was measured using ELISA kit (Abbot Laboratories, India). Anti-HBs titres of > 10 IU/L were taken as criteria of positive seroconversion. In group A seroconversion rate was 87.5%, 66.6% and 35.7% in mild, moderate and severe CRF respectively while same results in group B were 100%, 77% and 36.36%, respectively. We conclude that patients of chronic renal failure should be vaccinated at very early stage of the disease using 40 micrograms of vaccine. Four doses schedule of 0,1,2,6 give better results than three doses schedule in early CRF.

Menin interacts with the AP1 transcription factor JunD and represses JunD-activated transcription

MEN1 is a tumor suppressor gene that encodes a 610 amino acid nuclear protein (menin) of previously unknown function. Using a yeast two-hybrid screen with menin as the bait, we have identified the transcription factor JunD as a direct menin-interacting partner. Menin did not interact directly with other Jun and Fos family members. The menin-JunD interaction was confirmed in vitro and in vivo. Menin repressed transcriptional activation mediated by JunD fused to the Gal4 DNA-binding domain from a Gal4 responsive reporter, or by JunD from an AP1-responsive reporter. Several naturally occurring and clustered MEN1 missense mutations disrupted menin interaction with JunD. These observations suggest that menin's tumor suppressor function involves direct binding to JunD and inhibition of JunD activated transcription.

Spontaneous rupture of hepatic hydatid cyst causing inferior vena cava thrombosis

We report a patient with an infected hepatic hydatid cyst, which spontaneously ruptured into the inferior vena cava, with resultant thrombosis of the inferior vena cava, and left renal, right common iliac and right external iliac veins.

Tuberculous mediastinitis: a rare presentation

Granulomatous mediastinitis is a rare condition, and tuberculosis and fungal infections are the most important causes of this potentially lethal condition. Tuberculous mediastinitis usually presents with fever, cough, dyspnoea and rarely, florid features of obstruction to intra-thoracic structures are seen. A case of tuberculous mediastinitis presenting as a suprasternal lump, a rare presentation, is described here.

MEN1 gene analysis in sporadic adrenocortical neoplasms

Adrenocortical tumors occur as sporadic tumors, as part of the multiple endocrine neoplasia type 1 (MEN1) syndrome or as part of other hereditary disorders. We recently cloned the MEN1 gene, a tumor-suppressor gene located on chromosome 11q13. Subsequently, we showed that sequential somatic inactivation of both alleles of the MEN1 gene contributes to the development of some sporadic endocrine neoplasms (parathyroid, enteropancreatic neuroendocrine, bronchial carcinoid, and pituitary tumors). We now studied whether somatic inactivation of the MEN1 gene contributes to the pathogenesis of sporadic adrenocortical neoplasms. Seven adrenocortical carcinomas, 2 adrenocortical carcinoma cell lines, and 11 aldosterone-secreting, 8 cortisol-secreting, and 5 nonsecreting benign adrenocortical tumors were studied. Seven tumors (5 of 5 carcinomas, 2 of 21 nonsecreting benign adenomas; P < 0.001) exhibited loss of heterozygosity on 11q13. All 33 tumors and cell lines were screened for mutation throughout the MEN1 open-reading frame and adjacent splice junctions. None exhibited a mutation within the MEN1-coding region. We conclude that somatic MEN1 mutation within the MEN1-coding region does not occur commonly in sporadic adrenocortical tumors, although the majority of adrenocortical carcinomas exhibit 11q13 loss of heterozygosity.

Glucocorticoid-induced type 1/type 2 cytokine alterations in humans: a model for stress-related immune dysfunction

Increased psychologic and physiologic stressors can have profound effects on the immune system. Previously believed to be immunosuppressive, there is mounting evidence that stress may actually induce a shift in the type 1/type 2 cytokine balance toward a type 2 cytokine response. Cortisol is elevated in response to stress and has been reported to alter cytokine production in murine and human peripheral blood mononuclear cells (PBMC). The current investigation examined the effects of dexamethasone (DEX) mimicking basal, stress, and supraphysiologic levels of cortisol on production of interferon-gamma (IFN-gamma) (type-1), interleukin (IL)-12p40 (type 1), IL-10 (type 2), and IL-4 (type 2) by human PBMC. Both supraphysiologic and stress levels of DEX decreased production of type 1 cytokines and either increased or maintained production of type 2 cytokines PBMC stimulated with phytohemagglutinin (PHA), immobilized anti-CD3, lipopolysaccharide (LPS) or tetanus. Although preincubation with DEX was sufficient to induce a type 2 switch in short-term mitogen cultures, PBMC cultures for extended periods of time required DEX at the initiation and throughout the duration of culture. Mifepristone, a glucocorticoid receptor antagonist, blocked the DEX-induced shift in the type 1/type 2 cytokine balance. These data demonstrated the ability of the glucocorticoid dexamethasone, to induce a shift in the type 1/type 2 cytokine balance toward a type 2 cytokine response and simulate the type 1/type 2 cytokine alterations observed in in vivo stress models. This model will allow detailed investigation of the cellular and molecular mechanisms of stress-induced immune alterations in humans.

Cytokine dysregulation associated with exam stress in healthy medical students

The mechanisms of stress-related immune alterations have not been fully elucidated. Cell-mediated immune responses as well as antibody and certain cytokines are reported as being suppressed during times of high stress. However, the role of suppression vs dysregulation has not been established in human stress models. The effect of exam stress on regulatory cytokines in 16 healthy medical students was assessed by measuring type-1 (IFN-gamma) and type-2 (IL-10) cytokines from 72-h PHA/PMA-stimulated PBMC 4 weeks before and 48 h after exams. Results demonstrated decreased IFN-gamma accompanied by increased IL-10 during exam stress that resulted in a decreased IFN-gamma:IL-10 ratio. There was a significant correlation between the cytokine response to PHA/PMA and number and subjective adjustment to daily hassles. Additionally, students who reported greater levels of loneliness also reported greater numbers of and poorer subjective adjustment to hassles. The differences were consistent in both males and females but did not correlate with AM cortisol levels. Additionally, when individuals were grouped into high vs low preexam hassle levels, the type-1/type-2 shift in the IFN-gamma:IL-10 ratio occurred in the low hassles group only. These data suggest that psychologically stressful situations shift type-1/type-2 cytokine balance toward type-2 and result in an immune dysregulation rather than overall immunosuppression. This may partially explain the increased incidence of type-2-mediated conditions such as increased viral infections, latent viral expression, allergic/asthmatic reactions, and autoimmunity reported during periods of high stress.

Comparative genomic hybridization analysis of human parathyroid tumors

Primary hyperparathyroidism is characterized by hypercalcemia and elevated parathyroid hormone levels. It can be caused by overactivity of one (adenoma or carcinoma) or more (hyperplasia or multiple adenoma) parathyroid glands. Parathyroid adenoma and hyperplasia are usually mono- or oligoclonal neoplasms. To establish whether parathyroid cancer has a genetic composition distinct from parathyroid adenoma, we analyzed 10 adenoma and 10 carcinoma cases by comparative genomic hybridization (CGH). Results show clear differences between the constitution of adenoma and carcinoma genomic DNA. The most frequent genomic alterations in adenoma included deletions on chromosomes 11, 17 (5 of 10 cases), and 22 (7 of 10 cases). In parathyroid carcinoma, frequent chromosomal deletions were on chromosome arm 1p (4 of 10 cases) and chromosome 17 (3 of 10 cases), and gains were on chromosome 5 (3 of 10 cases). Our data indicate that different genetic changes could contribute to the development of parathyroid adenoma and carcinoma; genomic losses predominate in adenoma, and gains along with some losses are found in carcinoma. Furthermore, the CGH results implicate several chromosomal regions that may harbor genes that could be potentially involved in the development of parathyroid adenoma and carcinoma.

The 1996 outbreak of dengue hemorrhagic fever in Delhi, India

A major outbreak of dengue hemorrhagic fever (DHF) affected more than 10,000 people in Delhi and neighboring areas in 1996. The outbreak started in September, peaked in October to November and lasted till early December. The clinical and laboratory data of 515 adult patients admitted to Lok Nayak Hospital, New Delhi were reviewed. Fever (100%), myalgias and malaise (96%), abdominal pain (10.2%) and vomiting (8.7%) were the prominent presenting features. Hemorrhagic manifestations were seen in all patients- a positive tourniquet test (21.2%), scattered petechial rash (23.07%), confluent rash (2.7%), epistaxis (38.4%), gum bleeds (28.06%) and hematemesis (22.86%) being the major bleeding manifestations. Hepatomegaly was observed in 96% of the patients. Laboratory investigations revealed thrombocytopenia, hemoconcentration and leukopenia. Serological confirmation with a microcapture ELISA technic was done in 143/515 patients. The mortality rate was 6.6% and, multiple bleeding manifestations, severe thrombocytopenia, hypoproteinemia and dengue shock syndrome (DSS) were associated with a higher mortality.

Artificial neural networks in pediatric urology: prediction of sonographic outcome following pyeloplasty

PURPOSE

Computerized artificial neural networks are analogous to biological neuronal systems. Since they may be trained to recognize the relevance of complex patterns in data, neural networks may be useful for decision making in the multifactorial management of ureteropelvic junction obstruction. We determine the ability of a customized neural network to predict sonographic outcome after pyeloplasty in children with ureteropelvic junction obstruction.

MATERIALS AND METHODS

A data set was constructed with 242 demographic, clinical, radiological and surgical elements. We analyzed the available retrospective data in 100 consecutive children who underwent unilateral pyeloplasty for ureteropelvic junction obstruction chosen from all 144 surgically treated for ureteropelvic junction obstruction between 1993 and 1995. One radiologist reviewed all film data and provided a final sonographic outcome designation in each case. We wrote a set of computer programs to construct a neural network. A composite 4-layer network was built with output nodes representing 4 possible sonographic outcomes. The 100 patient data set was randomly divided into 84 training and 16 testing examples.

RESULTS

The neural network correctly predicted all 5 of 5 significantly improved, 7 of 7 improved, 2 of 2 same and 2 of 2 worse sonogram results after pyeloplasty. Therefore, sensitivity and specificity were 100% for all 4 outcomes. Linear regression analysis of the data yielded inferior sensitivity and specificity values (52 to 94%), confirming that ureteropelvic junction obstruction is a nonlinear data analysis problem.

CONCLUSIONS

The 100% accuracy, sensitivity and specificity of our neural network in this pilot study provide evidence of the value of the neural computational approach for the modern exploration and modeling of the clinical problem of pediatric ureteropelvic junction obstruction.

Role of DNA probes in characterization of pathogenic and non-pathogenic E. histolytica

Various tests have been described to differentiate the pathogenic and non-pathogenic types of E. histolytica. Recently DNA hybridization has been described to differentiate between the two subtypes. Using common HMC probe the presence of E. histolytica in stool was confirmed. Then on the basis of hybridization with DNA probe P 145 (pathogenic) and B 133 (non-pathogenic) E. histolytica was characterized as being pathogenic and non pathogenic respectively. Out of 137 patients studied 88 were symptomatic and 49 asymtomatic. 65 patients harboured E. histolytica as proved by microscopic examination of stool. Sixty-eight stool samples tested positive for DNA hybridization with common HMC probe, this included 65 microscopy positive samples and 3 microscopy negative samples. This gives a sensitivity of 100% and 96% specificity. All the 68 samples were then subjected to hybridization with P 145 and B 133 DNA probes. Out of 88 symptomatic patients stool samples of 57 patients were microscopy positive, however 58 were positive by common HMC probe and all of these were P 145 (pathogenic) positive and B 133 (non-pathogenic) negative. Of the 49 asymptomatic cases 8 were E. histolytica positive on microscopy and 10 positive on hybridization with common HMC probe and all 10 were P 145 negative and B 133 positive. It can be thus concluded that DNA hybridization is a reliable way to differentiate between pathogenic and nonpathogenic E. histolytica.

Role of antigen specific circulating immune complexes in diagnosis of tuberculosis

SETTING

Tuberculosis is a public health problem worldwide. Early accurate diagnosis in patients with active disease is essential to reduce morbidity and mortality. Conventional methods for detection of Mycobacterium tuberculosis have given disappointing results.

OBJECTIVE

To evaluate the utility of detection of M. tuberculosis antigen in circulating immune complexes (CIC) for the diagnosis of tuberculosis.

METHOD

Eighty-four clinically diagnosed cases of mainly extra-pulmonary tuberculosis, 85 patients with diseases other than tuberculosis and 30 healthy controls, were evaluated for the presence of antigen of M. tuberculosis in CIC in serum using sandwich enzyme linked immunosorbent assay (ELISA).

RESULTS

In total, 22 out of 84 cases were positive for culture on Lowenstein Jensen medium; 76.5% (n = 65) of the clinically diagnosed patients (including 20 culture-positive cases) were found to be positive by ELISA. The difference in mean absorbance values of ELISA in cases of tuberculosis was significantly higher than in controls. The sensitivity of ELISA was 90.9% and the specificity was 93.04%.

CONCLUSION

Detection of M. tuberculosis antigen in CIC by ELISA has potential as a useful diagnostic tool for the rapid diagnosis of tuberculosis, especially extra-pulmonary forms where results of conventional methods of diagnosis are disappointing.

Immunohistochemical co-expression of human papillomavirus type 16/18 transforming (E6) oncoprotein and p53 tumour suppressor gene proteins in oesophageal cancer

Human papillomaviruses have been widely implicated as important etiologic agents in various squamous cell carcinomas including oesophageal carcinoma. p53 mutant oncoprotein has also been implicated in various tumours. Immunohistochemical analysis was employed to detect the co-expression of HPV and p53 mutant protein in biopsy specimens of patients of cancer oesophagus as well as controls. This analysis revealed a significantly higher immunopositivity (63%) of E6 oncoprotein of HPV 16/18 in carcinoma of the oesophagus. Immunoexpression of E6 oncoprotein of HPV did not alter significantly the degree of differentiation of the tumour. Seventy-seven percent of cases of oesophageal carcinoma showed strong immuno-staining for mutant p53 protein. A higher percentage (89%) of tissues showed immunoexpression of mutant p53 protein in conjunction with E6 oncoprotein of HPV 16/18 indicating a selective degradation of key cellular protein of p53 having regulatory properties which in turn leads to uncontrolled cellular proliferation. Therefore, coexpression of oncoprotein E6 of HPV 16/18 and mutant p53 protein may be considered as a "high risk" factor for progression to oesophageal malignancy.

Germline and somatic mutation of the gene for multiple endocrine neoplasia type 1 (MEN1)

Dideoxyfingerprinting was used to screen for germline and somatic MEN1 mutations. This method, applied to a panel of germline DNA from 15 probands with multiple endocrine neoplasia type 1 (MEN-1), allowed confident discovery of the MEN1 gene. Germline MEN1 mutation has been found in 47 out of 50 probands with familial MEN-1, in 7 out of 8 cases with sporadic MEN-1, and in 1 out of 3 cases with atypical sporadic MEN-1. Germline MEN1 mutation was not found in any of five probands with familial hyperparathyroidism. Somatic MEN1 mutations were found in 7 out of 33 parathyroid tumours not associated with MEN-1. Allowing for repeating mutations, a total of 47 different germline or somatic MEN1 mutations have been identified. Most predict inactivation of the encoded 'menin' protein. supporting expectations that MEN1 is a tumour suppressor gene. The 16 observed missense mutations were distributed across the gene, suggesting that many domains are important to its as yet unknown functions.

Identification and characterization of the multiple endocrine neoplasia type 1 (MEN1) gene

For nearly a decade since the mapping of the multiple endocrine neoplasia type 1 (MEN1) locus to 11q13 and the suggestion that it is a tumour suppressor gene, efforts have been made to identify the gene responsible for this familial cancer syndrome. Recently, we have identified the MEN1 gene by the positional cloning approach. This effort involved construction of a 2.8-Mb physical map (D11S480-D11S913) based primarily on a bacterial clone contig. Using these resources, 20 new polymorphic markers were isolated which helped to reduce the interval for candidate genes by haplotype analysis in families and by loss of heterozygosity (LOH) studies in approximately 200 tumours, utilizing laser-assisted microdissection to obtain tumour cells with minimal or no admixture by normal cells. The interval was narrowed by LOH to only 300 kb, and nearly 20 new transcripts that map to this region of 11q13 were isolated and characterized. One of the transcripts was found by dideoxyfingerprinting and cycle sequencing to harbour deleterious germline mutations in affected individuals from MEN-1 kindreds and therefore identified as the MEN1 gene. The type of germline mutations and the identification of mutations in sporadic tumours support the Knudson's two-hit model of tumorigenesis for MEN-1. Efforts are being made to identify the function of the MEN1 gene-encoded protein, menin, and to study its role in tumorigenesis.

Comparative effects of GnRH agonist therapy. Review of clinical studies and their implications

OBJECTIVE

To understand why differences in gonadotropin releasing hormone (GnRH) agonist therapeutic protocols may affect their efficacy and safety profiles, to understand the important study design facets regarding the literature on GnRH agonist treatment of endometriosis and to compare the efficacy and side effect profiles of FDA-approved GnRH agonist therapies used for the management of endometriosis and consider the implications.

STUDY DESIGN

Review of the English-language literature regarding the use of GnRH agonists for the management of endometriosis.

RESULTS

A limited number of studies are available that directly compare the effects of different GnRH agonists. However, contrary to medical opinion, it appears that there are significant differences between GnRH agonist therapies.

CONCLUSION

The data suggest that it may be possible to reduce doses or alter regimens of GnRH agonists so as to reduce side effects while maintaining efficacy.

In vivo alteration in type-1 and type-2 cytokine balance: a possible mechanism for elevated total IgE in HIV-infected patients

The progression of HIV infection has been associated with an increase in the plasma levels of total IgE. The mechanisms responsible for the increased IgE have not been elucidated. The type-1 and type-2 cytokine imbalance associated with HIV infection has been proposed as a possible mechanism for elevated IgE. The current study was undertaken to investigate the relationship between total IgE, type-1 and type-2 cytokines from a large HIV+ patient population. HIV+ patients were found to have elevated total IgE that inversely correlated with numbers of CD4+ T-cells. HIV+ plasma was also found to have decreased IFN-gamma and IL-12p70 levels as well as increased IL-10 levels compared to HIV-negative individuals. HIV+ patients with more advanced disease, as defined by absolute CD4+ counts, demonstrated more marked differences. Furthermore, the relative ratios of IFN-gamma:IL-10 and IL-12:IL-10 were decreased in HIV+ patients compared to HIV-negative individuals. The alterations in the plasma cytokines suggest a switch from a predominance of type-1 cytokines to type-2 cytokines that may enhance IgE synthesis. These data suggest that measurement of plasma IgE and/or cytokines may have prognostic or therapeutic monitoring value in HIV+ patients.

Mutations of the MEN1 tumor suppressor gene in pituitary tumors

Although pituitary adenomas are monoclonal proliferations, somatic mutations involving genes that govern cell proliferation or hormone production have been difficult to identify. The genetic etiology of most pituitary tumors, therefore, remains unknown. Pituitary adenomas can develop sporadically or as a part of multiple endocrine neoplasia type 1 (MEN1). Recently, the gene responsible for MEN1 was cloned. To elucidate the potential etiological role of the MEN1 gene in pituitary tumorigenesis, 39 sporadic pituitary adenomas from 38 patients and 1 pituitary adenoma from a familial MEN1 patient were examined for MEN1 gene mutations and allelic deletions. Four of 39 sporadic pituitary adenomas showed a deletion of one copy of the MEN1 gene, and a specific MEN1 gene mutation in the remaining gene copy was detected in 2 of these tumors. The corresponding germ-line sequence was normal in all sporadic cases. A specific MEN1 mutation was detected in a pituitary adenoma and corresponding germ-line DNA in a patient with familial MEN1. An allelic deletion of the remaining copy of the MEN1 gene was also found in the patient's tumor. Genetic alterations of the MEN1 gene represent a candidate pathogenetic mechanism of pituitary tumorigenesis. The data suggest that somatic MEN1 gene mutations and deletions play a causative role in the development of a subgroup of sporadic pituitary adenomas.

A study on transferable R-plasmids among Shigella species at Lucknow

A total of 500 Shigella strains were included in the present study out of which 233 were isolated at National Shigella Centre of Postgraduate Department of Microbiology, K.G. Medical College, Lucknow during last 5 years and 267 strains were received from different parts of the country. Predominent serotypes were Sheigella flexneri 292 (48.4%) followed by Shigella dysenteriae 153 (30.6%), Shigella boydii 32 (6.4%) and Shigella sonnei 23 (4.6%). All the strains were sensitive to Nalidix acid, Gentamycin, Kanamycin, Neomycin and Furazolidine. Varying degree of resistance was shown to Streptomycin, Chloramphenicol, Tetracycline and Ampicillin. R. plasmid extraction was done and transfer was studied on E. Coli K-12.