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P Sharma

Publications and source records attributed to P Sharma.

At least 145 records · Page 8Linked to original sources
PubMed2000

beta2-adrenoceptor gene polymorphisms and blood pressure variations in East Anglian Caucasians.

OBJECTIVE: The amino-terminal polymorphisms, Arg16Gly and Gln27Glu, of the beta2-adrenergic receptor (beta2AR) have been shown to affect regulation of the receptor expression by an agonist in cell culture studies. The Arg16Gly polymorphism has also been recently shown to be associated with essential hypertension. We therefore evaluated whether the amino-terminal polymorphisms of beta2AR are associated with hypertension in a Caucasian population. SUBJECTS AND METHODS: We performed an association study in 298 hypertensive patients and an equal number of age-matched normotensive controls from the East Anglian region, with blood pressure assessed categorically and quantitatively. We also examined the influence of the amino-terminal polymorphisms on blood pressure response to beta-blockade in 144 of the patients randomly assigned to this class of drug. Genotyping of the Arg16Gly polymorphism was undertaken by a newly designed mismatched polymerase chain reaction (PCR) and digestion with Nde I, whereas the Gln27Glu polymorphism was genotyped by PCR followed by Fnu4H I cleavage. RESULTS: We found no differences in the genotype or allele frequencies of the beta2AR polymorphisms between hypertensive and normotensive participants. There was also no association between the beta2AR genotypes and variations in either basal blood pressure or the blood pressure response to a beta-blocker. CONCLUSION: These findings suggest that the amino-terminal polymorphisms of the beta2AR gene are unlikely to constitute major susceptibility for essential hypertension in the East Anglian population.

Adrenergic beta-Antagonists↗
PubMed2000

Association between diastolic blood pressure and variants of the endothelin-1 and endothelin-2 genes.

The genes for endothelin (ET) and their receptors are candidates for essential hypertension. Those for ET-1, ET-2 and the ET(A) receptor were selected for mutation scanning, and associated studies comparing untreated hypertensive patients and matched controls. A number of silent polymorphisms were found, resulting from a single nucleotide insertion or a single nucleotide substitution. There were no significant differences in the frequency of any one of these between the two groups. However, for ET-1 and ET-2 there were significant differences in the quantitative measurements of blood pressure and the number of variant alleles. The variants which we have found are likely to be in linkage disequilibrium with so far undiscovered variants in the regulatory regions of the genes.

3' Untranslated Regions↗
PubMed2000

Cysticercosis of the optic nerve.

Cysticercosis of the optic nerve has been reported only twice in the literature. A case of optic nerve cysticercosis in a 50-year-old woman with atypical optic neuritis is reported. Computerized tomography showed a thickened left optic nerve with a ring-enhancing lesion containing an eccentric nodule. An enzyme-linked immunosorbent assay test for cysticercosis further established the diagnosis. The patient was treated with oral prednisolone and albendazole, with no improvement in vision.

Albendazole↗
PubMed2000

Survey of internal medicine residents' use of the fecal occult blood test and their understanding of colorectal cancer screening and surveillance.

OBJECTIVE: Primary care physicians have imperfect understanding of current colorectal cancer screening guidelines and recommendations. Furthermore, compliance with colorectal cancer screening by internal medicine residents has been demonstrated to be poor. We sought to identify whether current trainees in internal medicine had adequate understanding of colorectal cancer screening and surveillance and test utilization. METHODS: We applied a structured questionnaire about colorectal cancer screening and the use of fecal occult blood tests to 168 internal medicine residents at four accredited programs in the U.S. They were also asked for recommendations about six hypothetical patients who may have been candidates for screening or surveillance. RESULTS: Seventy-one percent identified 50 yr as the currently recommended age to commence screening in an average-risk individual; 64.3% would begin screening with fecal occult blood testing and flexible sigmoidoscopy and 4.8% with colonoscopy. Most perform fecal occult blood testing on stool obtained at digital rectal exam and without prior dietary restrictions. Many use fecal occult blood testing for indications other than colorectal cancer screening. Only 29% recommended colonoscopy to evaluate a positive fecal occult blood test. Most residents plan to be screened for colorectal neoplasia at the appropriate age; significantly more opted for colonoscopy than recommended it for their patients. CONCLUSIONS: Internal medicine residents have many misperceptions regarding colorectal cancer screening and the utility of the fecal occult blood test. Educational efforts should be directed at internal medicine residents, many of whom plan careers in primary care, where most colorectal cancer screening is currently performed.

Adult↗
PubMed2000

Long-term follow-up of Barrett's high-grade dysplasia.

OBJECTIVE: The management of Barrett's high-grade dysplasia (HGD) remains controversial. The aims of this study were to evaluate prospectively the outcome of unifocal HGD (uHGD) in patients with Barrett's esophagus, and to determine demographic and endoscopic features predictive of progression to multifocal HGD (mHGD) and/or adenocarcinoma. METHODS: Consecutive Barrett's patients in whom uHGD was found at initial endoscopy or during surveillance underwent intensification of medical treatment and repeat endoscopy. The study endpoint was progression to mHGD or adenocarcinoma or HGD in conjunction with a dysplasia-associated lesion or mass (DALM). HGD diagnosis was confirmed by a second, blinded pathologist. RESULTS: A total of 15 Barrett's patients with uHGD met inclusion criteria and have been prospectively followed for a mean +/- SD of 36.8 +/- 23.2 months. All were white and male, with a mean age +/- SD of 61.4 +/- 14.9 yr. Barrett's length varied from 1 to 13 cm (mean, +/- SD, 6.8 +/- 4 cm). Overall, eight (53.3%) uHGD progressed: four of 15 (26.7%) to frank cancer between 17 and 35 months of follow-up, two of 15 (13.3%) to mHGD with DALM in conjunction with one or more foci of possible intramucosal cancer after 12-91 months of follow-up, one of 15 (6.7%) to mHGD with a focus of possible intramucosal cancer after 14 months, and one of 15 (6.7%) to mHGD after 29 months. Seven of 15 (46.7%) uHGD have regressed, five to no dysplasia and two to LGD, over the course of follow-up ranging from 24 to 73 months (mean +/- SD, 43.3 +/- 19.9). All three patients with short-segment Barrett's esophagus with uHGD regressed. Fisher's exact test revealed that Barrett's length > or =3 cm and presence of hiatal hernia approached significance (p < 0.08) in predicting uHGD progression to mHGD/DALM/cancer. However, use of the log-rank test to account for differences in length of follow-up show no significance for hiatal hernia or Barrett's length. CONCLUSIONS: Barrett's uHGD has a high risk for progressing to mHGD or cancer. Justification of an observational approach to uHGD should be discouraged. Markers of uHGD progression, as well as regression, are needed.

Adenocarcinoma↗
PubMed2000

Helicobacter pylori eradication dramatically improves inflammation in the gastric cardia.

OBJECTIVES: Inflammation of the gastric cardia, i.e., "carditis," has been associated with Helicobacter pylori (H. pylori) infection; however, some investigators believe carditis to be a histological marker for gastroesophageal reflux disease. The aim of this study was to investigate the role of H. pylori eradication on the grade of carditis scored according to the updated Sydney classification. METHODS: Consecutive patients presenting for upper endoscopy underwent systematic gastric biopsies (eight antral, 12 corpus, and four cardia). Patients with H. pylori infection and carditis were identified and followed prospectively before and after H. pylori treatment. At pretreatment and, on average, 2 yr after eradication of H. pylori, the degree of inflammation in the gastric cardia and H. pylori status were blindly assessed by a single pathologist. RESULTS: A total of 31 patients with H. pylori infection and carditis were identified. The mean age was 70 yr (range: 37-81 yr); all were male. Four were African-American and 27 were Caucasian. All patients were treated with standard anti-H. pylori therapy, including a proton pump inhibitor in combination with two antibiotics for 2 wk. Eradication of H. pylori was successful in 23 patients (group I), whereas eight patients had persistent infection (group II). Patients were followed after eradication therapy for a mean of 23.2 months (range: 6-48 months). After eradication therapy, there was a significant decrease (p < 0.0001) in the carditis scores (activity and inflammation scores) in group I, whereas the scores remained unchanged in group II patients. In both groups, there were no significant changes in the degree of intestinal metaplasia or atrophy. There were four patients with intestinal metaplasia, and one with atrophy. CONCLUSIONS: There is a dramatic improvement in the degree of inflammation and activity scores in the gastric cardia of patients with successful H. pylori eradication compared to those with persistent infection. By fulfilling one of Koch's postulates (i.e., improvement in the disease after cure of the possible etiological organism), these data support H. pylori as being the etiological agent for carditis in this group of patients.

Aged↗
PubMed2000

Relative risk of dysplasia for patients with intestinal metaplasia in the distal oesophagus and in the gastric cardia.

BACKGROUND: Biopsy specimens obtained from the gastro-oesophageal junction can reveal intestinal metaplasia in patients presenting for routine upper endoscopy. The site of biopsy may play a critical role in determining the dysplasia risk of a patient. AIMS: To evaluate prospectively the dysplasia risk in patients with intestinal metaplasia of the distal oesophagus or within the gastric cardia. METHODS: Patients with short segment Barrett's oesophagus (SSBO) and cardia intestinal metaplasia (CIM) were followed prospectively. RESULTS: 177 patients with SSBO were identified (mean age 62 years, range 38-82; 91% whites). Twenty prevalence cases of dysplasia in SSBO were detected: 17 low grade dysplasia (LGD), three high grade dysplasia (HGD). Seventy six patients with CIM were identified (mean age 67 years, range 37-81; 81% whites). A single prevalence case of LGD in CIM was detected. During follow up of 78 SSBO and 34 CIM patients, dysplasia developed in nine (seven LGD, two HGD) with SSBO and in one (LGD) with CIM. There were significant differences between the two groups with respect to age, ethnicity, dysplasia prevalence, and incidence. Time to dysplasia progression was significantly longer in CIM compared with SSBO patients. Of the five patients with SSBO and HGD, one developed adenocarcinoma of the oesophagus on follow up. No HGD or cancers have been detected over this time period in CIM patients. CONCLUSIONS: The dysplasia risk is significantly greater in SSBO than in CIM patients, indicating two potentially different clinical processes. Future studies should separate SSBO from CIM in order to enhance the understanding of the pathophysiology and malignant potential of each entity.

Adenocarcinoma↗
PubMed2000

Description of a simple test for CADASIL disease and determination of mutation frequencies in sporadic ischaemic stroke and dementia patients.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare inherited adult onset disease characterised most commonly by cerebral ischaemic events and dementia. It is caused by mutations in the Notch3 gene with most clustering in exons 3 and 4. Whether these mutations have any influence on common sporadic ischaemic stroke or dementia cases has not been investigated, partly hampered by the lack of a readily usable genetic test. An easy to use diagnostic array for CADASIL was designed using various restriction endonucleases for the known mutations in exons 3 and 4 and novel mismatch primers were designed where no such enzymes existed. This array was used to identify the allele frequencies of CADASIL mutations and polymorphisms in selected disease cohorts. Seventy patients with radiologically established sporadic ischaemic stroke and 77 patients from a specialist young dementia clinic were recruited. One hundred and seventeen age and sex matched asymptomatic controls were also identified. The diagnostic array was found to work well. None of the 14 known mutations and three previously identified polymorphisms (C474A, A587G, and C594A) in exons 3 and 4 were present in 140 stroke, 110 dementia, or 234 control chromosomes. Molecular variant C381T occurred with a higher frequency of 0.13, whereas G684A occurred with a lower frequency (0.09) than previously reported, although there were no statistical differences between selected cohorts. In conclusion, a readily usable genetic test for CADASIL has been devised that was used to determine allele frequencies in well characterised cohorts of sporadic stroke and dementia patients. The data suggest that despite the clinical resemblance, CADASIL is not a common masquerading cause of stroke or dementia. The test will enable units locally to rapidly screen patients with suspected CADASIL.

Adult↗
PubMed2000

The impact of hearing on communication.

The study was designed to assess the impact of hearing impairment on communication between older hospital patients and medical staff and to see whether intervention to improve hearing influences perceived communication. Structured interviews were held with 200 mentally alert elderly hospital in-patients before and after the introduction of voice amplifiers and acetate cards depicting a hearing problem. Prior to intervention 22% of patients rated communication with their doctor as poor or unsatisfactory. Following intervention there was a significant improvement (Chi-square p=0.006), with only 6% of patients reporting communication with their doctor as poor or unsatisfactory. Most of the patients who felt communication was unsatisfactory could not hear what was being said. We conclude that simple measures can improve the number of older patients hearing what their doctor says and improve their perception of communication with the hospital doctor.

Aged↗
PubMed2000

Molecular determinants for the distinct pH sensitivity of Kir1.1 and Kir4.1 channels.

Kir1.1 (ROMK1) is inhibited by hypercapnia and intracellular acidosis with midpoint pH for channel inhibition (pK(a)) of approximately 6.7. Another close relative, Kir4.1 (BIR10), is also pH sensitive with much lower pH sensitivity (pK(a) approximately 6. 0), although it shares a high sequence homology with Kir1.1. To find the molecular determinants for the distinct pH sensitivity, we studied the structure-functional relationship using site-directed mutagenesis. An NH(2)-terminal residue (Lys-53) was found to be responsible for the low pH sensitivity in Kir4.1. Mutation of this lysine to valine (K53V), a residue seen at the same position in Kir1. 1, markedly increased channel sensitivity to CO(2)/pH. Reverse mutation on Kir1.1 (V66K) decreased the CO(2)/pH sensitivities. Interestingly, mutation of these residues to glutamate greatly enhanced the pH sensitivity in both channels. Other contributors to the distinct pH sensitivity were histidine residues in the COOH terminus, whose numbers are fewer in Kir4.1 than Kir1.1. Mutation of two of these histidine residues in Kir1.1 (H342Q/H354N) reduced CO(2)/pH sensitivities, whereas the creation of two histidines (S328H/G340H) in Kir4.1 increased the CO(2)/pH sensitivities. Combined mutations of the lysine and histidine residues in Kir4.1 (K53V/S328H/G340H) gave rise to a channel that had CO(2)/pH sensitivities almost identical to those of the wild-type Kir1.1. Thus the residues demonstrated in our current studies are likely the molecular basis for the distinct pH sensitivity between Kir1.1 and Kir4.1.

Amino Acid Sequence↗
PubMed2000

A genome-wide search for susceptibility loci to human essential hypertension.

We undertook a systematic search of the entire human genome with the affected sibling-pair model to identify major susceptibility loci to essential hypertension. Affected nuclear families (n=263) were recruited and divided according to definite or probable genetic contribution to hypertension depending on number of hypertensive siblings. The largest nuclear families were first screened with a set of microsatellite markers. Regions on the genome with P<0.05 were tested against the second set of smaller families. An exclusion map was generated to identify regions in which hypertension-causing genes are unlikely to reside. Sibling-pair linkage analysis identified a single locus on chromosome 11q (P<0.004) in the first pass. A second pass with nuclear families that had only affected sibling pairs was, as expected, insufficient to support linkage to 11q. Multipoint exclusion-linkage analysis showed that 3 genetic loci are necessary to explain familial aggregation of essential hypertension. Our preliminary findings suggest that no single region within the human genome contains genes with a major contribution to essential hypertension. We show that the disease is indeed polygenic, with each gene providing a relatively small risk. Our exclusion map will help future investigators to concentrate on areas likely to contain these genes. The region on chromosome 11 is the first to point to a new candidate gene for hypertension that has arisen out of a genome search, but replication of these results at a higher significance is necessary before positional cloning can be justified.

Aged↗
PubMed2000

Effects of poststroke pyrexia on stroke outcome : a meta-analysis of studies in patients.

BACKGROUND AND PURPOSE: The effect of pyrexia on cerebral ischemia has been extensively studied in animals. In humans, however, such studies are small and the results conflicting. We undertook a meta-analysis using all such published studies on the effect of hyperthermia on stroke outcome. METHODS: Three databases were searched for all published studies that examined the relationship of raised temperature after stroke onset and eventual outcome. Combined probability values and odds ratios were obtained. A heterogeneity test was performed to ensure that the data were suitable for such an analysis. Morbidity and mortality were used as outcome measures. RESULTS: Nine studies were identified totaling 3790 patients, providing our study with 99% power to detect a 9% increase in morbidity and 84% power to detect a 1% increase in mortality for the pyrexial group. The combined odds ratio for mortality was 1.19 (95% CI, 0.99 to 1.43). A heterogeneity test was highly nonsignificant (P>0.05) for mortality, suggesting that the data were sufficiently similar to be meta-analyzed. Combined probability values were highly significant for both morbidity (P<0.0001) and mortality (P<0. 00000001). CONCLUSIONS: The results from this meta-analysis suggest that pyrexia after stroke onset is associated with a marked increase in morbidity and mortality. Measures should be taken to combat fever in the clinical setting to prevent stroke progression. The possible benefit of therapeutic hypothermia in the management of acute stroke should be further investigated.

Aged↗
PubMed2000

Mycobacterium w vaccine, a useful adjuvant to multidrug therapy in multibacillary leprosy: a report on hospital based immunotherapeutic clinical trials with a follow-up of 1-7 years after treatment.

A vaccine based on autoclaved Mycobacterium w was administered, in addition to standard multidrug therapy (MDT), to 156 bacteriologically positive, lepromin negative multibacillary leprosy patients compared to a well matched control group of 145 patients with a similar type of disease who received a placebo injection in addition to MDT. The MDT was given for a minimum period of 2 years and continued until skin smear negativity, while the vaccine was given at 3-month intervals up to a maximum of eight doses. The fall in clinical scores and bacteriological indices was significantly more rapid in vaccinated patients, from 6 months onward until years 2 or 3 of therapy. However, no difference was observed in the fall in bacteriological index in the two groups from year 4 onwards. The number of LL and BL patients released from therapy (RFT) following attainment of skin smear negativity, after 24-29 months of treatment was 84/133 (63.1%) in vaccinated and 30/120 (25.0%) in the placebo group; the difference was highly statistically significant (P < 0.0001). In all, 90.2% patients (146/162) converted from lepromin negativity to positivity in the vaccine group, as against 37.9% (56/148) in the placebo group. The average duration of lepromin positivity maintained following eight doses of vaccine administered over 2 years was 3.016 years in the vaccine and 0.920 years in the placebo group. Histological upgrading after 2 years of treatment in the LL type was observed in 34/84 (40.5%) cases in the vaccine and 5/85 (5.9%) cases in the placebo group, the difference being statistically significant (P < 0.001). The incidence of type 1 reactions was significantly higher (30.5%) in the vaccine group than (19.7%) in the placebo group (P = 0.0413); the difference was mainly observed in LL type (P = 0.009). The incidence of type 2 reactions was similar (31.8 and 34.6%) in vaccine and placebo groups. The vaccine did not precipitate neuritis or impairments over and above that encountered with MDT alone. After 5 years of follow-up following RFT, no incidence of bacteriological or clinical relapses was observed in both groups.

Bacterial Vaccines↗
PubMed2000

Reactional states and neuritis in multibacillary leprosy patients following MDT with/without immunotherapy with Mycobacterium w antileprosy vaccine.

A vaccine based on autoclaved Mycobacterium w was administered, in addition to standard multidrug therapy (MDT), to 157 untreated, bacteriologically positive, lepromin negative multibacillary leprosy patients, supported by a well matched control group of 147 patients with similar type of disease, who received a placebo injection in addition to MDT. The MDT was given for a minimum period of 2 years and continued until skin smear negativity, while the vaccine/placebo was given at 3-monthly intervals up to a maximum of eight doses. The incidence of type 2 reaction and neuritis during treatment and follow-up showed no statistically significant difference in the vaccine and placebo groups. The incidence of type 1 reaction (mild in most cases), however, was higher in the vaccine group (P = 0.041, relative risk ratio 1.79), considering LL, BL and BB leprosy types together, and considerably higher (P = 0.009) in LL type, probably because of confounding due to higher number of patients with previous history of reaction in this group. The occurrence of reactions and neuritis in terms of single or multiple episodes was similar in the vaccine and placebo groups. The association of neuritis and reactions, as well as their timing of occurrence (during MDT or follow-up), was also similar in the two groups, with more than 90% of occurrences taking place during MDT. The incidence of reversal reaction was significantly higher among the males in the vaccine group (34.5% versus 8.3%, P = 0.019). Patients with high initial BI (4.1-6.0) showed higher incidence of reactions (70.3%) as compared to those with medium (2.1-4.0) and low (0.3-2.0) BI where the reactions were observed with a frequency of 56.1% and 38.8%, respectively. However, unlike reactions, neuritis incidence did not seem to be affected by initial BI to the same extent in the vaccine group, with frequencies of 35.3%, 36.3% and 25.9% in the three mentioned BI ranges. Overall, the vaccine did not precipitate reactional states and neuritis over and above that observed with MDT alone.

Bacterial Vaccines↗
PubMed2000

Induction of lepromin positivity and immunoprophylaxis in household contacts of multibacillary leprosy patients: a pilot study with a candidate vaccine, Mycobacterium w.

We screened 487 household contacts of multibacillary (MB) patients for evidence of disease and their lepromin status. From the 444 results available, 302 (68.02%) were lepromin positive and 142 (31.98%) were lepromin negative on initial testing. The initial lepromin status as assessed in the group of 54 contacts having disease at the outset showed 24 out of 46 (52.2%) to be lepromin positive and 22 of 46 (47.8%) to be lepromin negative. In the same group, among 24 lepromin positives, 22 (91.7%) had paucibacillary (PB) and 2 (8.3%) had multibacillary (MB) disease; among the lepromin negatives, 12 (54.5%) had PB and 10 (45.5%) had MB disease. Out of 72 initially lepromin-negative contacts administered Mycobacterium w vaccine and followed up, the cumulative percentages show that 53 (73.6%) converted to positivity after a single dose, 10 (87.5%) after a second dose and 67 (93.1%) after the third dose. The incidence of new cases with leprosy was 8 out of 231 (3.46%) among lepromin-positive contacts and 5 out of 93 (5.38%) among lepromin-negative contacts administered Mycobacterium w vaccine. Among 231 lepromin-positive contacts, the new cases occurred in those with a 1+ and 2+ lepromin response only, and no case occurred among 51 contacts with a 3+ lepromin response. The incidence among lepromin-positive contacts in this study (3.46%) was similar to the observations in two other studies: 3.2% by Dharmendra, et al. and 6.9% by Chaudhary, et al. However, the incidence among lepromin-negative contacts administered Mycobacterium w vaccine was significantly lower than that observed among lepromin-negative contacts not administered any vaccination in the other two studies (14.1% by Dharmendra, et al. and 29.0% by Chaudhary, et al.). To conclude, although a study of small sample size, the preliminary evaluation indicates that administration of Mycobacterium w vaccine seems to have the potential to reduce the incidence of leprosy among household contacts of leprosy patients. More explicit results about the vaccine will be available from the ongoing field trials in Kanpur Dehat in the near future.

Bacterial Vaccines↗
PubMed2000

Eye tracking disturbances in schizophrenia.

PURPOSE: To study the frequency of different types of eye tracking disturbances in schizophrenia. MATERIALS AND METHODS: Smooth pursuit eye movements were studied by electro-oculography (EOG) in 22 schizophrenic patients (ICD-10 criteria) and 15 age and sex-matched controls. The studied parameters included average pursuit gain, number of saccades, the frequency of different types of saccades (catch-up, back-up, anticipatory saccades), and disturbances during fixation. The results were analysed statistically. RESULTS: The average pursuit gain was significantly affected in patients for target velocity of 30 degrees/sec (p = 0.007). The catch-up and back-up saccades were more common in cases than controls but the difference was not significant (p = 0.39 and 0.36 respectively). The anticipatory saccades were significantly more frequent in cases than controls (p < 0.0001) for both 15 degrees/sec and 30 degrees/sec target velocities. This was also correlated with the duration of illness. CONCLUSION: Anticipatory saccades are significantly more frequent during eye tracking in schizophrenia and appear to be an objective marker for the disease.

Adult↗