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R Mehrotra

Publications and source records attributed to R Mehrotra.

At least 19 recordsLinked to original sources
PubMed2000

Treatment of advanced renal failure: low-protein diets or timely initiation of dialysis?

Until 1996, no guidelines existed for the initiation of dialysis in patients with progressive renal failure. The publication of the National Kidney Foundation-Dialysis Outcome Quality Initiative guidelines has generated a debate on the management of advanced renal failure and the role of low-protein diets (LPDs). We performed a review of the literature to identify articles on the initiation of dialysis and LPDs, particularly those since 1996. Delayed referral of patients is widespread in both the United States and Europe, and almost 25% of patients are started on dialysis at a glomerular filtration rate (GFR) of <5 mL/min/1.73 m2. There is a high prevalence of malnutrition at the time of first dialysis, which progressively improves upon initiation of dialysis. There is no evidence regarding the efficacy or safety of LPDs in nondiabetic patients younger than 70 years old [approximately 40% of U.S. incident end-stage renal disease (ESRD) patients] and in diabetics with GFR <25 mL/min/1.73 m2 (>40% of incident U.S. ESRD). In nondiabetics who are younger than 70 years old, adherence to LPD for four to five years can be estimated to result in a delay in dialysis by 6 to 11 months. However, suboptimal energy intake is widespread in advanced renal failure, which declines further upon institution of LPD. Even nutritionally sound patients develop subclinical nutritional decline despite intense counseling. There are no data on the efficacy or safety of LPD in subgroups that constitute approximately 80% of incident ESRD patients. Concerns still exist regarding their nutritional safety in the remainder. Initiation of dialysis results in improved nutritional status and should be considered in a timely fashion.

Diet, Protein-Restricted↗
PubMed2000

Overexpression of p53 protein in gallbladder carcinoma in North India.

AIMS: p53 mutations are one of the most frequent genetic alterations in human cancers and are thought to play a role in pathogenesis of several malignancies. Overexpression of p53 in gallbladder cancer has not previously been reported from North India which has one of the highest incidence of this malignancy in the world. The present work is aimed at studying the overexpression of p53 in gallbladder carcinoma occurring in North India. METHODS: p53 overexpression by immunohistochemistry was studied in 20 operative specimens of gallbladder carcinoma. The clinico-pathological observations of these patients were correlated with the extent of p53 overexpression. RESULTS: Seventy per cent (14/20) of specimens of gallbladder carcinoma overexpressed p53 protein. There was a significant correlation between presence of gallstones, T stage, grade of tumour and liver invasion with p53 overexpression. There was no significant correlation with other factors studied viz. age, sex, nodal status and histological type. CONCLUSIONS: The results show a strong association between gallstones and p53 protein overexpression in gallbladder carcinoma. The causal relationship in this association, however, still remains unproven.

Adult↗
PubMed2000

Immunohistochemical localization and correlation of p53 and PCNA expression in breast carcinoma.

The object of the present study is to detect the p53 tumour suppressor gene and proliferation cell nuclear antigen (PCNA) expression in breast carcinoma by immunohistochemistry and correlate them with the prognostic parameters. Total 35 cases of primary breast carcinoma were studied and classified histologically. Paraffin sections were stained by using monoclonal antibody D07 for p53 protein and PC-10 for PCNA. Out of 35 cases, 16 (45.7%) were p53 positive and 25 (71.4%) were PCNA positive. The mean PCNA labelling index (PCNA LI +/- SD) was 58.97 +/- 22.72 in tumors positive for both p53+ and PCNA+ while cases negative for p53- and positive for PCNA+ has higher PCNA LI +/- SD (59.24 +/- 18.97). The difference in the two groups was not significant. Most cases were positive for both p53+ and PCNA+ in the age group < 30 with higher mean PCNA LI +/- SD (62.20 +/- 27.13) than in the group > 30 (57.88 +/- 18.47). In the pre-menopausal group 57.1% cases were positive for p53+ with higher PCNA LI +/- SD (59.94 +/- 24.22). Maximum p53 and PCNA positivity was observed in grade III tumors (63.2% and 84.2%). The mean PCNA LI +/- SD was also highest in grade III carcinomas (66.83 +/- 13.97). No significant correlation was found between p53 and PCNA status with morphological type and tumour size except that logistic regression showed a positive correlation with tumour grade. Therefore the present study suggests that both p53 expression and PCNA are markers of poor differentiation in breast cancer.

Adult↗
PubMed2000

Cytodiagnosis of tuberculosis of the skull by fine needle aspiration cytology: a case report.

Close to one-third of the world's population is believed to be infected with tuberculosis, with the vast majority being in the developing world. However, even in the developed world, the incidence of this disease has been steadily increasing. Tuberculosis is very common in the Indian subcontinent, but at the same time tuberculous infection of the skull is rare and very few cases have been reported. We report a child who presented with a swelling of the frontal bone of the skull. Fine needle aspiration yielded the cytological diagnosis of tuberculosis on the basis of a necrotising granulomatous process with acid-fast bacilli detected on Ziehl Neelsen stain. This procedure obviated the need for an operative procedure and the patient responded to anti-tuberculous therapy. As the incidence of tuberculous infection is on the increase, both in the developed and in the developing world, the importance of diagnosis by newer non-invasive techniques like fine needle aspiration cytology cannot be overemphasized. To the best of our knowledge, this is the first report of its kind in the world literature.

Biopsy, Needle↗
PubMed2000

Peritoneal dialysis in adult patients without end-stage renal disease.

End-stage renal disease remains the primary indication for the use of peritoneal dialysis. The therapy, however, has been used for the treatment of various other clinical conditions. Evidence has accumulated to support the use of peritoneal dialysis to maintain euvolemia, to improve functional status, and to reduce hospitalizations in patients with intractable chronic congestive heart failure. The use of peritoneal dialysis as a modality for core rewarming in patients with severe hypothermia has been established; in selected circumstances, it is probably the therapy of choice. The field of oncology has borrowed heavily from the technique of peritoneal dialysis for administering intraperitoneal chemotherapy; even though the therapy remains largely experimental today, it has great future potential. While efficacious in the treatment of acute, diuretic-resistant volume overload in patients with congestive heart failure and in patients with severe, disabling psoriasis, the introduction of alternative methods of management have rendered the use of peritoneal dialysis obsolete. Finally, the role of peritoneal lavage in the management of patients with pancreatitis remains controversial and is no longer routinely used.

Adult↗
PubMed1999

IR investigation on dehydrophenylalanine containing model peptides in helical conformation deposited on a crystal surface

Fourier transform ir spectra have been recorded for three 3(10)-helical and one alpha-helical pentapeptides containing dehydrophenylalanine, in a thin solid film, in order to find marker bands for various secondary structures encountered in peptides containing dehydroaminoacids. The peptide solutions were deposited and dried as thin film on zinc selenide crystal surface. This convenient sampling method has provided reliable estimates of peptide secondary structure in solid state. Detailed vibrational assignments in the spectral region between 1200-1700 cm(-1) are reported. In this region, peptide amide I, II, and III vibrations occur. Spectra-structure correlation has been presented based on the amide modes. Comparison of the ir spectra with available crystal structure data provides qualitative support for assignments of ir bands to 3(10)-helical structure and alpha-helical structure in dehydrophenylalanine containing pentapeptides. Band frequency assignments for 3(10)-helical conformation are consistent for all three peptides. All the assignments agree closely with the theoretical predictions. The spectral differences between 3(10)-helical peptides and the alpha-helical peptide have been highlighted. These findings demonstrate that a method based on ir spectroscopy can be developed for a useful approximation of three-dimensional structure of dehydropeptides in solid state. Copyright 1999 John Wiley & Sons, Inc.

Journal Article↗
PubMed1999

Fine-needle aspiration biopsy of orbital meningioma.

Fine-needle aspiration was performed on an orbital mass in a 53-yr-old woman. The cytologic diagnosis was meningioma, which was later confirmed by histologic study of biopsy material. The cytologic features of the aspirated material (nuclear pseudoinclusions, psammoma bodies, and cells arranged in syncytial sheets and whorls) allowed a rapid, reliable, outpatient diagnosis to be formulated. The cytologic features are discussed and the literature is reviewed. Diagn. Cytopathol. 1999;21:402-404.

Biopsy, Needle↗
PubMed1999

Salivary mucin MG1 is comprised almost entirely of different glycosylated forms of the MUC5B gene product.

The MG1 population of mucins was isolated from human whole salivas by gel chromatography followed by isopycnic density gradient centrifugation. The reduced and alkylated MG1 mucins, separated by anion exchange chromatography, were of similar size (radius of gyration 55-64 nm) and molecular weight (2.5-2.9 x 10(6) Da). Two differently-charged populations of MG1 subunits were observed which showed different reactivity with monoclonal antibodies to glycan epitopes. Monosaccharide and amino acid compositional analyses indicated that the MG1 subunits had similar glycan structures on the same polypeptide. An antiserum recognizing the MUC5B mucin was reactive across the entire distribution, whereas antisera raised against the MUC2 and MUC5AC mucins showed no reactivity. Western blots of agarose gel electrophoresis of fractions across the anion exchange distribution indicated that the polypeptide underlying the mucins was the product of the MUC5B gene. Amino acid analysis and peptide mapping performed on the fragments produced by trypsin digestion of the two MG1 populations yielded data similar to that obtained for MUC5B mucin subunits prepared from respiratory mucus (Thornton et al., 1997) and confirmed that the MUC5B gene product was the predominant mucin polypeptide present. Isolation of the MG1 mucins from the secretions of the individual salivary glands (palatal, sublingual, and submandibular) indicate that the palatal gland is the source of the highly charged population of the MUC5B mucin.

Amino Acids↗
PubMed1999

Effect of helium-neon laser on wound healing.

To estimate the biostimulatory effects of low intensity laser radiation on healing of skin wounds, two linear skin wounds were produced on either side of dorsal midline in rats and immediately sutured. Wounds on the left side were irradiated daily with helium neon laser at 4 Joules/sq.cm for 5 min., while those on right side were not exposed and served as controls. The mean time required for complete closure in control group was 7 days while irradiated test wounds took only 5 days to heal (P < 0.01). The mean breaking strength, as measured by the ability of the wound to resist rupture against force, was found to be significantly increased in the test group. Early epithelization, increased fibroblastic reaction, leucocytic infiltration and neovascularization were seen in the laser irradiated wounds. The results establish the biostimulatory effects of low intensity laser radiation on healing of skin wounds.

Animals↗
PubMed1999

Trends in initiation of dialysis in an urban dialysis clinic in the United States: a long way from dialysis outcomes quality initiative guidelines.

The guidelines issued for peritoneal dialysis by the National Kidney Foundation Dialysis Outcomes Quality Initiative (NKF-DOQI) suggest initiation of dialysis at a glomerular filtration rate (GFR) of 10.5 mL/min/1.73 m2. We undertook this study to determine trends at a center in Philadelphia. Using the MDRD (Modification of Diet in Renal Disease) formula, we estimated the GFR (mL/min/1.73 m2) at the time of first dialysis for patients starting on dialysis at the center between 1994 and 1996. Data on 72 of the 86 new patients were available. Of the 72, 69 patients (96%) were black and 29 (40%) were diabetic. The estimated GFR at the time of dialysis initiation was 6.3 +/- 0.3 mL/min/1.73 m2. Only 3 patients (4%) had a GFR > 10.5; 25 patients (35%) had GFR < 5.0. Patients with a lower GFR had more severe acidosis (HCO3 15.8 +/- 0.5 mmol/L vs 19.5 +/- 0.9 mmol/L, p = 0.0023) and greater impairment in divalent ion metabolism (PO4: 7.6 +/- 0.2 mg/dL vs 5.6 +/- 0.3 mg/dL, p < 0.0001). Diabetic patients were initiated on dialysis at a higher level of GFR than non diabetic patients (7.2 +/- 0.3 mL/min/1.73 m2 vs 5.7 +/- 0.4 mL/min/1.73 m2, p = 0.0087). Even though diabetic patients had higher GFR and lower serum creatinine (8.6 +/- 0.5 mg/dL vs 11.8 +/- 0.9 mg/dL, p = 0.0021) than non diabetic patients, blood urea nitrogen (BUN) was similar in the two groups (89 +/- 3.7 mg/dL vs 96.8 +/- 5.8 mg/dL, p = 0.73). This difference may indicate that nondiabetic patients had a greater decline in protein intake. Finally, a trend towards initiation of dialysis at higher levels of renal function was seen with time (GFRs 5.5 +/- 0.4 mL/min/1.73 m2, 6.4 +/- 0.4 mL/min/1.73 m2, and 6.9 +/- 0.6 mL/min/1.73 m2 for 1994, 1995, and 1996 respectively; p = 0.058, 1994 vs 1996). The trend was stronger for diabetic patients (GFR 6.3 +/- 0.4 mL/min/1.73 m2 and 8.1 +/- 0.7 mL/min/1.73 m2 for 1994 and 1996 respectively; p = 0.06) than for non diabetic patients (GFR 5.1 +/- 0.5 mL/min/1.73 m2 and 6.2 +/- 0.7 mL/min/1.73 m2 for 1994 and 1996 respectively; p = 0.22). We conclude that initiation of dialysis is delayed in urban centers, particularly in non diabetic patients, and that the current practice is far below the DOQI recommendations.

Diabetes Mellitus↗
PubMed1998

Isolation and physical characterization of the MUC7 (MG2) mucin from saliva: evidence for self-association.

Saliva contains two major families of mucins (MG1 and MG2); the polypeptide of the smaller of these glycoproteins (MG2) has been assigned as the product of the MUC7 gene. In this study we have devised a rapid two-step procedure that recovers this glycoprotein essentially free of other components and in sufficient quantity to enable physical and self-interaction studies. Raw saliva was solubilized in 4 M guanidinium chloride and thereafter subjected to Sepharose CL-4B chromatography. The MG2-rich fraction was recovered free from the larger MG1 glycoproteins and also smaller proteins/glycoproteins (molecular mass less than 100 kDa). MG2 glycoproteins were finally purified by anion-exchange chromatography on Mono Q. The purity of the preparation was assessed by SDS/PAGE after radiolabelling of the molecules with [14C]acetic anhydride. Peptide mapping, N-terminal sequencing and amino acid analysis verified the polypeptide of the mucins as the MUC7 gene product. The isolated molecules were examined by electron microscopy and appeared as short flexible worm-like structures 30-120 nm in length. The distribution was heterogeneous, containing a major component with number-average and weight-average lengths of 52 and 55 nm respectively and a minor component with number-average and weight-average lengths of 94 and 98 nm respectively. We propose that the two differently sized populations represent monomeric and dimeric species of the mucins. Gel chromatography performed in 0.2 M NaCl indicated the presence of monomers, dimers and tetramers; an average molecular mass for the preparation was 192 kDa. However, in 4 M guanidinium chloride the molecular mass was 158 kDa and a similar molecular mass (155 kDa) was determined for the mucin preparation after reduction. These results suggest that the mucins might self-associate via a protein-mediated interaction. On the basis of the results a model is proposed for the self-association of the MUC7 mucin, which might be important for its biological function.

Acetic Anhydrides↗
PubMed1998

Surgical experience with intracardiac myxomas: long-term follow-up.

BACKGROUND: Myxomas are the most common benign intracardiac tumors. This report summarizes our 20-year experience with these tumors. METHODS: Sixty-six patients (25 male) with a median age of 39 years (range, 6 to 70 years) underwent surgical excision of primary or recurrent intracardiac myxomas during the years 1976 to 1996. Symptom duration ranged from 2 to 8 months. There were 55 left atrial myxomas, 10 right atrial myxomas, and 1 biatrial myxoma. Three of the patients were in one family. The surgical approach comprised complete wide excision. RESULTS: There were two early deaths. Late follow-up is 89% (57/64) complete. There was one late death, which was not due to a cardiac cause. Echocardiography at a mean follow-up of 66.9 months (range, 7 to 241 months) showed no recurrence of sporadic myxomas. However, 2 of the 3 patients with familial myxomas had recurrence. CONCLUSIONS: Surgical excision of atrial myxoma gives excellent short-term and long-term results leading to eventual cure of nonfamilial myxomas. However, familial myxomas retain a strong tendency to recur even 20 years after excision.

Adolescent↗
PubMed1998

A, B & H isoantigens in cervical lesions.

Expression of A, B and H isoantigens in cervical mucosa was demonstrated by specific red cell adherence test in 92 cervical lesions (40 chronic cervicitis, 12 dysplasia and 40 carcinoma cervix). Eighty percent cases of chronic cervicitis showed a moderate reaction. On the contrary, in carcinoma cervix, 75% cases were found to be SRCA negative. In dysplasia, the intensity of red blood cell adherence was found to be directly related to the degree of cellular differentiation. Study of A, B and H isoantigens might help in deciding the prognosis of dysplasia and/or early detection of malignancy.

ABO Blood-Group System↗
PubMed1998

Interleukin 13 is secreted by human head and neck tumours and does not modulate their growth in vitro.

Expression of interleukin-13 (IL-13) has been examined in head and neck cancer cell lines. This interleukin was expressed by all human head and neck carcinoma cells studied, though in varying degrees. The effect of exogenous IL-13 on growth of squamous cell carcinomas of the head and neck cell lines was also studied. It was found that this cytokine did not modulate the proliferation of four cell lines studied. These results demonstrate that human squamous cell carcinoma of the head and neck secrete IL-13.

Carcinoma, Squamous Cell↗
PubMed1998

"EXPATH" an expert system for pathology for the diagnosis of jaundice.

Computers are increasingly playing an important role in the field of medicine. A computer aided expert system has been developed for the differential diagnosis of jaundice. In this article the major features and application of this modular software are discussed.

Diagnosis, Computer-Assisted↗