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S Upadhyay

Publications and source records attributed to S Upadhyay.

At least 19 recordsLinked to original sources
PubMed2001

Indole-3-carbinol (I3C) induced cell growth inhibition, G1 cell cycle arrest and apoptosis in prostate cancer cells.

Prostate cancer is one of the most common cancers in men and it is the second leading cause of cancer related death in men in the United States. Recent dietary and epidemiological studies have suggested the benefit of dietary intake of fruits and vegetables in lowering the incidence of prostate cancer. A diet rich in fruits and vegetables provides phytochemicals, particularly indole-3-carbinol (I3C), which may be responsible for the prevention of many types of cancer, including hormone-related cancers such as prostate. Studies to elucidate the role and the molecular mechanism(s) of action of I3C in prostate cancer, however, have not been conducted. In the current study, we investigated whether I3C had any effect against prostate cancer cells and, if so, attempts were made to identify the potential molecular mechanism(s) by which I3C elicits its biological effects on prostate cancer cells. Here we report for the first time that I3C inhibits the growth of PC-3 prostate cancer cells. Induction of G1 cell cycle arrest was also observed in PC-3 cells treated with I3C, which may be due to the observed effects of I3C in the up-regulation of p21(WAF1) and p27(Kip1) CDK inhibitors, followed by their association with cyclin D1 and E and down-regulation of CDK6 protein kinase levels and activity. The induction of p21(WAF1) appears to be transcriptionally upregulated and independent of the p53 responsive element. In addition, I3C inhibited the hyperpohosphorylation of the Retinoblastoma (Rb) protein in PC-3 cells. Induction of apoptosis was also observed in this cell line when treated with I3C, as measured by DNA laddering and poly (ADP-ribose) polymersae (PARP) cleavage. We also found an up-regulation of Bax, and down-regulation of Bcl-2 in I3C-treated cells. These effects may also be mediated by the down-regulation of NF-kappaB observed in I3C treated PC-3 cells. From these results, we conclude that I3C inhibits the growth of PC-3 prostate cancer cells by inducing G1 cell cycle arrest leading to apoptosis, and regulates the expression of apoptosis-related genes. These findings suggest that I3C may be an effective chemopreventive or therapeutic agent against prostate cancer.

Anticarcinogenic Agents↗
PubMed2001

An organically modified silicate-based ethanol biosensor.

A novel electrocatalytic ethanol biosensor using ferrocene-encapsulated palladium (Pd)-linked organically modified sol-gel glass (ormosil) is reported. The alkoxy precursors used to prepare the new ormosil-based electrocatalytic biosensor are Pd-linked glycidoxypropyltrimethoxysilane and trimethoxysilane. Pd-glycidoxypropyltrimethoxysilane (black solution) is made by mixing aqueous solutions of palladium chloride and glycidoxypropyltrimethoxysilane. The new ormosil is made using a Pd-linked silane precursor, trimethoxysilane, an aqueous solution of ferrocene monocarboxylic acid, and HCl. Alcohol dehydrogenase (ADH) is assembled over the ferrocene-ormosil layer using polyvinyl alcohol and then protecting the immobilized enzyme layer using Millipore filter membranes (pore size 1 microm). The electrocatalytic response of immobilized ADH, soluble nicotinamide adenine dinucleotide, and Pd-linked ormosil-encapsulated ferrocene is then observed. The electrocatalytic oxidation of NADH and the subsequent ADH-catalyzed formation of NADH are monitored electrochemically. Typical results recorded after the addition of varying concentrations of ethanol are reported; however, the sensor is sensitive to other alcohol and known ADH-sensitive substrates. The stability and reproducibility of the new ethanol biosensor are reported.

Alcohol Dehydrogenase↗
PubMed2001

Differential sensitivity of normal and malignant breast epithelial cells to genistein is partly mediated by p21(WAF1).

Genistein, a soy metabolite, is a potential chemopreventive agent against various types of cancer. There are several studies documenting molecular alterations leading to cell cycle arrest and induction of apoptosis in a variety of cancer cells; however, no studies, to date, have shown the effect of genistein in isogenic normal and malignant breast epithelial cells. In this study, we investigated whether genistein shows any differential sensitivity to normal (MCF10A and MCF12A) and malignant (MCF10CA1a and MDA-MB-231) breast epithelial cells. We found that genistein causes a greater degree of G(2)-M arrest and induces apoptosis in malignant cell lines compared with normal breast epithelial cells. After genistein treatment, flow cytometric analysis revealed a hyperdiploid population in malignant cells that was not observed in normal cells. Cell cycle regulator p21(WAF1), which is known to be up-regulated by genistein treatment, was greatly induced at RNA and protein levels in normal cells, whereas its level was only slightly induced in malignant MDA-MB-231 cells and not detectable in malignant MCF10CA1a cells. Therefore, we investigated the causal role of p21(WAF1) in the differential sensitivity of genistein among these cell lines. We examined the effects of genistein on p21(WAF1) -/- and p21(WAF1) +/+ HCT116 cells, which were used as controls prior to studies on breast cancer cells. We found that there was a greater degree of cell cycle arrest and apoptosis in p21(WAF1) -/- cells compared with p21(WAF1) +/+ HCT116 cells after genistein treatment. Flow cytometric analysis after genistein treatment showed a significant number of p21(WAF1) -/- cells in the hyperdiploid population, which are probably programmed to die through apoptotic processes. To further confirm the causal role of p21(WAF1) in genistein-mediated cell cycle arrest and apoptosis, we down-regulated p21(WAF1) by antisense p21(WAF1) cDNA transfection experiments. We found that both normal and malignant p21(WAF1) antisense (AS)-expressing clones became more sensitive to G(2)-M arrest after genistein treatment. Flow cytometric analysis showed an increase in the hyperdiploid population in the AS clones. Further evaluation showed an increase in apoptosis in malignant AS clones but not in normal breast epithelial AS clones. These results suggest that p21(WAF1) may play an important role in determining the sensitivity of normal and malignant breast epithelial cells to genistein.

Antineoplastic Agents↗
PubMed2001

Morphological and functional characteristics of rabbit uterine epithelial cells grown on free floating collagen gel.

In the present study isolated uterine epithelial cells from normal rabbits were maintained in culture on free floating rat-tail collagen matrix, and the morphological characteristics of these cells were examined. Additionally, the pattern of protein synthesis and secretion by rabbit uterine epithelial cells grown on free floating collagen gels following estradiol and/or progesterone treatment in vitro was examined. Isolated epithelial cells cultured on collagen gels in complete medium containing serum attached to form monlayers, and eventually the gels became free floating and contracted giving rise to luminal arrangements. These cells were cytokeratin positive epithelial cells and were ultrastructurally polarized. These cells also exhibited differential upregulation and down regulation in the synthesis and secretion of proteins in response to estradiol, progesterone, and estradiol plus progesterone. Additionally, a permissive action between progesterone and estradiol in the synthesis of two species of secretory proteins was observed. It however remains to be examined whether different species of proteins produced in vitro in response to estradiol and progesterone bear any association with physiological states in reproductive cycle in this species.

Animals↗
PubMed1999

Induction of apoptosis in breast cancer cells MDA-MB-231 by genistein.

Breast cancer is the most common cancer among American women, whereas Asian women, who consume a traditional diet high in soy products, have a relatively low incidence. Genistein is a prominent isoflavonoid in soy products and has been proposed as the agent responsible for lowering the rate of breast cancer in Asian women. We investigated the effects of genistein on cell growth and apoptosis-related gene expression in breast cancer cells MDA-MB-231. We found up-regulation of Bax and p21WAF1 expressions and down-regulation of Bcl-2 and p53 expression in genistein-treated cells. Furthermore, DNA ladder formation, CPP32 activation, and PARP cleavage were observed after treatment with genistein, indicating apoptotic cell deaths. Flow cytometry with 7-amino actinomycin D staining showed that the number of apoptotic cells increased with longer treatment of genistein. From these results, we conclude that genistein inhibits the growth of MDA-MB-231 breast cancer cells, regulates the expression of apoptosis-related genes, and induces apoptosis through a p53-independent pathway. The up-regulation of Bax and p21WAF1 may be the molecular mechanisms by which genistein induces apoptosis, however, further definitive studies are needed. These results suggest that genistein may be a potentially effective chemopreventive or therapeutic agent against breast cancer.

Apoptosis↗
PubMed1998

Ethanol biosensors and electrochemical oxidation of NADH.

Comparative studies of the electrochemical oxidation of reduced nicotinamide coenzyme (NADH) at the surfaces of chemically modified graphite paste electrodes (CMEs) are reported. Three different electroactive materials, tetracyanoquinodimethane (TCNQ), tetrathiafulvalene (TTF), and dimethyl ferrocene (dmFc), were used to construct three different chemically modified paste electrodes. The oxidation of NADH was examined on the basis of cyclic voltammetric measurements. The results show that all three mediators (TCNQ, TTF, and dmFc) behave as efficient mediators of the oxidation of NADH. The typical response curves of NADH at the CMEs surfaces are reported. Incorporating alcohol dehydrogenase and electroactive materials (TCNQ, TTF, and dmFc) within the graphite paste electrodes has led to the development of ethanol biosensors. Typical response curves for the ethanol analysis are reported. Comparative studies on the mediated electrochemical responses of the biosensors to ethanol are discussed.

Biosensing Techniques↗
PubMed1997

Peroxide biosensors and mediated electrochemical regeneration of redox enzymes.

This article describes the research investigations on the development of the amperometric biosensors based on mediated bioelectrochemistry. The mediated bioelectrochemistry involving horseradish peroxidase and glucose oxidase within the graphite paste is reported. The enzyme horseradish peroxidase together with electrochemical mediator was incorporated within the graphite paste electrode. The amperometric response is based on the mediated electrochemical regeneration of peroxidase within the paste. The mediated electrochemical regeneration of peroxidase and glucose oxidase was studied and compared using three different electron transfer mediators-tetracyanoquinodimethane (TCNQ), tetrathiafulvalene (TTF), and dimethyl ferrocene (dmFc). The mediated electrochemistry involving these three mediators was studied based on the cyclic voltammetry. The electrochemical measurements show that TTF is better mediator for the development of peroxide biosensor compared to TCNQ and dmFc. On the other hand, TCNQ is better mediator for the development of glucose sensor. The response curves for peroxide have been reported using these three mediators. A comparative study on the amperometric response based on the mediated electrochemical oxidation of peroxidase and glucose oxidase has also been made using these three mediators. The various parameters, i.e., background current, stability of the mediator within the graphite paste during the electrochemical measurements, and reproducibility of the amperometric response, are discussed.

Biosensing Techniques↗
PubMed1996

Cytomegalovirus sinusitis. A new manifestation of AIDS.

Cytomegalovirus is a common pathogen in patients infected with the human immunodeficiency virus. In this article, cytomegalovirus sinusitis is described and documented for the first time, to our knowledge. Cytomegalovirus was cultured from the sinuses of four patients who were positive for the human immunodeficiency virus and who had antibiotic-resistant infections. In one patient who underwent surgery, cytomegalovirus inclusions were documented consistent with invasive infection. Optimal treatment has yet to be determined, but in this case surgery did provide temporary relief of sinus symptoms.

AIDS-Related Opportunistic Infections↗
PubMed1996

Identification of human sperm antigen recognized by serum of an immunoinfertile woman: a candidate for immunocontraception.

PROBLEM: It has been well documented that antisperm antibodies can be causative factors of infertility. In this study we have identified an antigen on human sperm surface using serum of an immunoinfertile woman; it is thus a candidate for immunocontraception. METHOD: Thirty-three women of reproductive age who were infertile were screened for presence of antisperm antibodies by indirect immunofluorescence and agglutination assay. The serum of one such woman, SU-4, reacted with her husband's as well as normal donor sperm and recognized a band of apparent molecular weight of 71-kDa on Western blot. Anti-71-kDa antiserum was raised in rabbit by eluting 71-kDa protein and was characterized by agglutination test, immunofluorescence assay, transmission electron microscopy, flow cytometry, and sperm-egg interaction in mouse system. RESULTS: Interestingly, sera raised in rabbit against 71-kDa antigen, was identified by immunoinfertile serum of SU-4, revealed similar results of localization of human acrosome. Anti-71-kDa antibodies showed cross-reactivity with other species of sperm, demonstrated inhibition of sperm attachment to oocytes in an in vitro mouse system, and revealed surface binding of human live sperm by flow cytometry. Transmission electron microscopy documented the presence of 71-kDa antigen in the acrosomal compartment. CONCLUSION: This study has put in evidence an antigen of apparent molecular weight of 71-kDa in all donor sperm tested in this study. The presence of this antigen on the sperm of several species will enable us to determine the efficacy of this antigen in controlling fertility in vivo in both rodents and primates. This antigen may be a candidate for immunocontraception.

Adult↗
PubMed1995

bcl-2 suppresses expression of p21WAF1/CIP1 in breast epithelial cells.

The tumor suppressor gene p53 regulates G1 checkpoint prior to the initiation of DNA synthesis, which can either induce G1 arrest or signal apoptosis. The involvement of p53 in apoptosis may also be related to its ability to down-regulate transcription of the bcl-2 gene. The bcl-2 gene product prevents most types of apoptotic cell death, suggesting that bcl-2 interferes with an essential signaling molecule involved in the apoptotic cell death pathway. Although the bcl-2 protein is shown to be overexpressed in many types of human tumor including breast cancer, its biochemical or pathological consequences are poorly understood. To determine the effects of bcl-2 overexpression on apoptosis and transformation of breast epithelial cells and to investigate whether bcl-2 interferes with the p53 pathway, we introduced the bcl-2 expression vector into MCF10A cells, which were derived from diploid human breast epithelial cells containing the wild-type p53 gene. Overexpression of bcl-2 prevented free radical-induced apoptosis and induced a partially transformed phenotype in MCF10A cells. Although overexpression of bcl-2 did not affect the expression of the p53 gene, p53-dependent gene transcription such as p21WAF1/CIP1 was suppressed. These results suggest that bcl-2 may inhibit p53 functional activity and is involved in the regulation of an early commitment step either to proliferate or suicide.

Apoptosis↗
PubMed1995

Platelet-derived growth factor induces apoptosis in growth-arrested murine fibroblasts.

The platelet-derived growth factor (PDGF) is a potent mitogen for murine fibroblasts. PDGF-stimulated cells express a set of immediate-early-response genes but require additional (progression) factors in serum to progress through the cell cycle. Serum-deprived cells are reversibly arrested in G0 phase and fail to fully traverse the G1 phase of the cell cycle when stimulated by PDGF alone. We now report that serum-deprived normal rat kidney fibroblast (NRK) cells stimulated by either PDGF AA or PDGF BB homodimers undergo apoptotic cell death. Furthermore, we show that epidermal growth factor also induces apoptotic cell death in serum-deprived NRK cells, epidermal growth factor enhances the rate of apoptosis in PDGF-treated cells, and a progression factor (insulin) but not endogenously expressed Bc1-2 fully protects NRK cells from PDGF-stimulated apoptosis. The results indicate that PDGF induces apoptosis in growth-arrested NRK cells and that the inability of NRK cells to transit the G1/S checkpoint is the critical determinant in establishing the genetic program(s) to direct the PDGF signal to apoptosis. The results suggest that polypeptide growth factors in vivo may signal cell fate positively or negatively in settings that limit the potential of cells to completely transit the cell cycle.

Animals↗
PubMed1995

Mode of long-term antifertility effect of intrauterine neem treatment (IUNT).

The mode of antifertility action of intrauterine neem treatment (IUNT) was studied. The effect of IUNT on ovarian functions and uterine responsiveness to ovarian hormones was examined in adult Wistar rats. The treated animals had normal reproductive cycles as indicated by the vaginal smears; serum progesterone levels were also in the normal range. Effect of exogenous estradiol following IUNT in ovariectomized rats showed comparable uterine weight gain as in control group; decidual cell reaction of the uterine epithelium following IUNT was also similar to that of control, indicating normal uterine responsiveness to ovarian hormones. Unilateral IUNT followed by mating resulted in degeneration of embryos on the treated side as noted between days 3-5 post coitum; normal embryos were seen on the contralateral side given peanut oil. The study shows that the mode of antifertility action of IUNT is not because of uterine unresponsiveness to the ovarian hormones but is due to impairment of embryo development. The results of this study thus confirm our earlier observations and show further that the antifertility effect of IUNT is at the pre-implantation stage, localized and without any adverse or toxic effect on the fetal development in the contralateral uterine horn of the unilaterally treated rats. The exact mechanism(s) of antifertility action of IUNT is being investigated.

Animals↗
PubMed1995

Bacteriology of sinusitis in human immunodeficiency virus-positive patients: implications for management.

The bacteriology of sinusitis in human immunodeficiency virus (HIV)-infected patients has been only sporadically reported. In this study, we report the results of cultures taken from 12 HIV patients with refractory chronic sinusitis who underwent surgery. Nine of the 12 patients had positive cultures with 16 isolates and 5 patients having multiple isolates. Five of the 12 patients grew out atypical or opportunistic infections not responsive to standard medical therapy, including 3 patients with cytomegalovirus, 1 with Aspergillus fumigatus, and 1 with Mycobacterium kansasii. These results suggest the need for aggressive medical care for HIV-infected patients with sinusitis and early intervention for tissue cultures in patients who do not respond to standard antibiotic regimens.

AIDS-Related Opportunistic Infections↗
PubMed1994

Platelet-derived growth factor (PDGF) B and A homodimers transform murine fibroblasts depending on the genetic background of the cell.

The endogenously overexpressed c-sis (platelet-derived growth factor (PDGF) B-chain) proto-oncogene and its viral counterpart v-sis effectively transform NIH 3T3 cells by an autocrine mechanism, whereas the PDGF A-chain gene does not. However, PDGF B continuously cultured with confluent NIH 3T3 cells fails to induce phenotypic transformation as would be predicted by the autocrine model. We now have established conditions in which subconfluent, logarithmically growing NIH 3T3 cells are efficiently transformed by exogenous PDGF B but not PDGF A. Clonally selected cells from transformed foci remain transformed when continuously cultured with PDGF B but revert to the non-transformed phenotype without PDGF B or if PDGF A is substituted for PDGF B, suggesting that PDGF B complements a genetically stable NIH 3T3 cell phenotype to induce transformation and initiates a signal different from that of PDGF A required to induce transformation. Neither PDGF A nor PDGF B transform normal rat kidney (NRK) cells under identical conditions of culture. However, we now demonstrate that exogenous PDGF A and PDGF B independently transform NRK cells that endogenously overexpress the anti-apoptotic bcl-2 gene. These results suggest that both PDGF A and PDGF B effectively transform murine fibroblasts with a compatible genotype, that transformation by the PDGF isoforms requires complementation with a compatible genotype in a multistep transformational process, and that the autocrine mechanism is required but not sufficient for transformation of murine fibroblasts by PDGF.

3T3 Cells↗
PubMed1994

Long-term contraceptive effects of intrauterine neem treatment (IUNT) in bonnet monkeys: an alternate to intrauterine contraceptive devices (IUCD).

Antifertility effects of intrauterine neem treatment (IUNT) was studied in bonnet monkeys. A single administration of 1 ml of neem oil by an intrauterine insemination catheter blocked fertility for 7 to 12 months. The effect was, however, reversible as all the animals became pregnant subsequently and delivered normal babies. The neem oil treatment had no adverse effect on menstrual cyclicity and ovarian functions. The uterus of neem-treated animals showed normal morphology. Immunohistological studies, however, demonstrated a significant increase in the number of MHC-II antigen-positive cells in the uterine endometrium following neem treatment, indicating enhanced antigen-presenting ability of the uterus; a feature that may be related to the observed antifertility effect of neem oil. The present investigation demonstrates that an IUNT can be used for long-term, reversible contraception, without any apparent side effects, and that the method could provide an alternate to currently used intrauterine contraceptive devices (IUCD).

Animals↗
PubMed1993

Hydrolytic enzymes of rhesus placenta during Plasmodium cynomolgi infection: ultrastructural and biochemical studies.

Placenta in monkey demonstrated altered pathophysiology after P cynomolgi infection. The electronmicroscopic observations showed slight complete focal necrosis of the placental tissue, besides alterations in total protein, phosphatases and proteinases. These changes in cellular constituents of placenta during malaria infection may be responsible for malfunctioning of the organ and in turn, abnormal development of foetus.

Animals↗
PubMed1992

Analysis of muscarinic receptor subtypes in the mouse cochlea by means of the polymerase chain reaction.

Total RNA was extracted with guanidine thiocyanate from the cochleas of 16-day-old CBAJ mice. The mRNA was purified from the total RNA using oligo-dT cellulose, and the mRNA was treated with DNase to degrade genomic DNA. After reverse transcription, resulting cDNA was amplified by polymerase chain reaction (PCR), using primers specific for the nucleotide sequences m1-m5, representing subtypes of muscarinic acetylcholine receptors. PCR products corresponding to subtypes m1, m3, and m5, but not to m2 and m4, were amplified. These results suggest that muscarinic acetylcholine receptors of these odd-numbered subtypes are expressed in the mammalian cochlea.

Animals↗