Search PubMed⌕ Search

Biomedical subjects

S Bansal

Publications and source records attributed to S Bansal.

At least 55 records · Page 3Linked to original sources
PubMed1996

Mucosal tolerance and suppression of collagen-induced arthritis (CIA) induced by nasal inhalation of synthetic peptide 184-198 of bovine type II collagen (CII) expressing a dominant T cell epitope.

The purpose of the study was to map the dominant T cell epitope of the CB11 sequence of CII in RTlu haplotype rats and to determine if, when used as a synthetic peptide, it would induce tolerance to protect against CIA. A dominant epitope corresponding to residues 184-198 included in the sequence of the CB11 fragment of bovine CII was identified in proliferation assay using peptides in an epitope scanning system using synthetic peptides of 15 amino acids, overlapping by 12 amino acids. This epitope is bovine-specific, but cross-reacts with the corresponding rat peptide. Minor epitopes in the bovine CB11 sequence was also autoantigenic. Use of independently synthesized and purified 184-198 peptide confirmed its dominance in the T cell responses of arthritic rats. The peptide itself was not arthritogenic. Cells from lymph nodes draining arthritic feet were particularly responsive to the dominant peptide sequence, and showed evidence of epitope spreading to include reactions to at least four subdominant epitopes. Mucosal tolerance was successfully induced by instilling CII into the nose of rats before induction of CIA: this was found to delay the onset of disease, reduce mean disease severity, shift the anti-CII antibody response to favour antibodies of the IgG1, rather than the IgG2b isiotype, and to reduce T cell reactivity to both CII and to the 184-198 peptide. The dominant 184-198 peptide itself had the same tolerogenic effects when given nasally to rats daily, on the 4 days immediately preceding the induction of CIA. Two forms of CIA with acute and delayed disease onset were each modified by pre-treatment with the peptide. This study demonstrates that mucosal tolerance to CII can be induced by delivering it nasally in a way similar to that achieved previously by oral delivery, and that the use of an immunodominant epitope contained in a synthetic peptide will also suppress the immunologic and arthritic responses to collagen.

Administration, Inhalation↗
PubMed1996

Effect of nitrendipine, nimodipine and nisoldipine on water and electrolytes excretion in rats.

In water loaded (5 ml/100 g) unanesthetized rats. nitrendipine (NT), nimodipine (NM) and nisoldipine (NS) (5 mg/ kg, i.p.) caused significant (P < 0.01) increase in water and Na+ excretion. However, there was no significant increase in K+ excretion after NT, NM and NS administration. NS was more potent in increasing excretion of water load as compared to NT and NM. The glomerular filtration rate as assessed by creatinine clearance, was significantly (P < 0.01) increased in NT, NM and NS (5 mg/kg, i.p.) treated groups as compared to control. The mean creatinine clearance values after NT, NM and NS were 26.95 +/- 0.35, 22.11 +/- 0.72 and 28.13 +/- 0.95 respectively as compared to 22.19 +/- 0.51, 18.77 +/- 0.42 and 22.97 +/- 0.60 in corresponding control groups. The results of the study suggest that in addition to other effects, NT, NM and NS have a selective inhibitory effect on Na+ handling mechanisms in the nephron.

Animals↗
PubMed1995

Molecular mimicry and ankylosing spondylitis: possible role of a novel sequence in pullulanase of Klebsiella pneumoniae.

Molecular mimicry has been shown between two sequences of Klebsiella pneumoniae pulD secretion protein (DRDE) with HLA-B27 (DRED) and pulA (pullulanase) enzyme (Gly-X-Pro) with types I, III and IV collagen respectively. IgG antibody levels in AS patients were elevated against 16mer synthetic peptides of HLA-B27 and pulD by enzyme immunosorbent assay (ELISA) compared to controls (P < 0.001). ELISA assays against K. pneumoniae grown in the absence and presence of pullulan demonstrated significant levels of IgA antibody in AS patients compared to controls (P < 0.001). Increased IgA and IgG antibody levels to pulA and types I and IV collagen were observed in AS patients compared to controls (P < 0.001). These observations could be relevant in the sequence of molecular events in AS.

Amino Acid Sequence↗
PubMed1995

Bilateral renal oncocytomatosis in a patient with renal failure.

Bilateral multifocal renal oncocytomas are very rare disorders with only 6 previously reported cases in the world literature, of which only 3 have had pathologic confirmation. We present the first reported case of diffuse, bilateral, multifocal renal oncocytomatosis in a patient with end-stage renal disease requiring hemodialysis. Our patient was found to have hundreds of nodular tumors in both kidneys on exploration, representing the second such reported finding.

Adenoma, Oxyphilic↗
PubMed1995

Professional and business characteristics of radiology groups in the United States: 1992.

PURPOSE: In response to requests, to present information on the professional and business characteristics of radiology groups. MATERIALS AND METHODS: The American College of Radiology surveyed a stratified random sample of radiology groups, defining radiology group as any practice with two or more radiologists or radiation oncologists, including academic departments, units in multispecialty groups, and staff of government facilities. The 465 responses (69% response rate) were weighted so the data show what findings would have been if all radiology groups in the country had responded. RESULTS: ACR professional standards are widely used, particularly those for mammography and radiation oncology. Seventy-eight percent of groups required continuing training of their technologists. On average, groups required 2.7 years for new members to become full partners. The average group gave full-time radiologists 11 holidays, 26 vacation days, and 11 days for continuing medical education each year. On average, groups collected 71% of total billings. Net collections (after "allowances" for Blue Shield, Medicare, and other payers are deducted from billings) averaged 86%; half of services were provided by groups with net collection rates of 90% or more. CONCLUSION: In general, changes since 1989 (when the previous Group Practice Survey was conducted) were small.

Data Collection↗
PubMed1995

Effect of raising endogenous testosterone levels in impotent men with secondary hypogonadism: double blind placebo-controlled trial with clomiphene citrate.

Secondary hypogonadism is not an infrequent abnormality in older patients presenting with the primary complaint of erectile dysfunction. Because of the role of testosterone in mediating sexual desire and erectile function in men, these patients are usually treated with exogenous testosterone, which, while elevating the circulating androgens, suppresses gonadotropins from the hypothalamic-pituitary axis. The response of this form of therapy, although extolled in the lay literature, has usually not been effective in restoring or even improving sexual function. This failure of response could be the result of suppression of gonadotropins or the lack of a cause and effect relationship between sexual function and circulating androgens in this group of patients. Further, because exogenous testosterone can potentially increase the risk of prostate disease, it is important to be sure of the benefit sought, i.e. an increase in sexual function. In an attempt to answer this question, we measured the hormone levels and studied the sexual function in 17 patients with erectile dysfunction who were found to have secondary hypogonadism. This double blind, placebo-controlled, cross-over study consisted of treatment with clomiphene citrate and a placebo for 2 months each. Similar to our previous observations, LH, FSH, and total and free testosterone levels showed a significant elevation in response to clomiphene citrate over the response to placebo. However, sexual function, as monitored by questionnaires and nocturnal penile tumescence and rigidity testing, did not improve except for some limited parameters in younger and healthier men. The results confirmed that there can be a functional secondary hypogonadism in men on an out-patient basis, but correlation of the hormonal status does not universally reverse the associated erectile dysfunction to normal, thus requiring closer scrutiny of claims of cause and effect relationships between hypogonadism and erectile dysfunction.

Adult↗
PubMed1995

Hospital activities of radiology groups in the United States: results of a 1992 ACR survey.

OBJECTIVE: To describe the hospital activities of radiology groups in the United States, including the characteristics of hospitals at which groups practice, workload and staffing at these hospitals, and groups' professional and business arrangements at these hospitals. MATERIALS AND METHODS: The American College of Radiology surveyed a stratified random sample of radiology groups, defining a radiology group as any practice with two or more radiologists or radiation oncologists, including private groups, academic or multispecialty groups, and staffs of government facilities. All groups were directed to complete a detailed, two-page hospital information sheet (HIS) for each hospital at which they practiced. Sixty-nine percent of groups responded, and we obtained HISs for 86% of their hospitals. These responses were weighted to make our results representative of all U.S. hospitals at which radiology groups practice. RESULTS: Radiology groups reported performing on average 47,800 diagnostic procedures annually at hospitals. The average number of diagnostic procedures (inpatient plus outpatient) performed was 0.8 per inpatient day. This number varied greatly from hospital to hospital. A full-time equivalent (FTE) diagnostic radiologist at a hospital performed on average 11,400 procedures annually. Again, variation was large; the 25th percentile was 7000 procedures annually per FTE, and the 75th percentile was 14,100 procedures. Radiation oncology services were mainly provided at larger hospitals (more than 300 beds). On average, the annual number of new oncology patients at hospitals offering radiation oncology services was 380, and these patients received an average of 8435 fractions. Groups accepted nonreferred patients for mammography at 42% of hospitals at which they provided diagnostic services, and they provided 24-hr coverage for diagnostic radiology at 80% of the hospitals at which they provided diagnostic services. CONCLUSIONS: Radiologists can use the findings from this survey to evaluate their hospital practice. The workload data show considerable variation, and averages should not be taken as standards.

Accounts Payable and Receivable↗
PubMed1995

Outside financial interests in radiology offices: prevalence, payment, and practice patterns in involved offices.

OBJECTIVE: The purposes of our study were to (1) investigate the prevalence of different patterns of outside financial interests in radiology offices and of different methods of compensating these interests and (2) determine how the professional, operational, and practice characteristics of the offices vary with the patterns of outside interest. The term "office" means nonhospital practice sites, including those called imaging centers or clinics; "outside interests" refers to parties other than physicians in the group of physicians who serve the office. MATERIALS AND METHODS: Data are for 516 office sites served by radiology groups. Data were collected as part of a national, stratified random sample survey of radiology groups in the United States done by the American College of Radiology in 1992. Responses were weighted to make the results representative of all radiology groups in the United States with offices. RESULTS: Parties other than the physicians in the practice serving an office had a financial interest in 41% of offices. In about half of these (20% of all offices), physicians in the practice had no financial interest at all. The most common categories of outside financial interest were referring physicians (21%), hospitals (19%), and non-physician entrepreneurs (12%); some offices reported more than one type of outside financial interest. All categories were more common in high-tech offices (offices that offered CT, MR imaging, or nuclear medicine studies) than in non-high-tech offices. Overall, 50% of high-tech offices and 35% of non-high-tech offices had outside financial interests. The most common method of compensating outsiders was giving them shares or dividends or a percentage of the profits. The average number of procedures per full-time-equivalent radiologist was higher in offices in which only outsiders (and not the group serving the office) had a financial interest than in other offices, and fewer of the former offices offered mammography. Offices with no outside interests were more likely than those with any outsiders to regularly do chest, spinal, gastrointestinal, and urologic procedures. CONCLUSIONS: Outside financial interests, and the problems of cost and access they may engender, are fairly common in radiology offices. Nationally, joint ventures including referring physicians, which are now under legal attack, number more than 500. Differences in who owns radiology offices were associated with statistically significant variations among offices in workload, staffing, and types of procedures done.

Analysis of Variance↗
PubMed1994

Pharmacokinetics of tazobactam M1 metabolite after administration of piperacillin/tazobactam in subjects with renal impairment.

Tazobactam is a new derivative of penicillinic acid sulfone, which functions as an irreversible inhibitor of many beta-lactamases. The disposition of tazobactam M1 metabolite after intravenous (i.v.) infusion of 3 g of piperacillin/0.375 g of tazobactam was evaluated in 26 subjects with various degrees of renal impairment. Participants in the study were 18 subjects with creatinine clearances (ClCR) ranging from 7.4-41.8 mL/min, 4 subjects maintained on continuous ambulatory peritoneal dialysis (CAPD), and 4 subjects undergoing chronic hemodialysis (HD). The pharmacokinetic parameters of piperacillin and tazobactam were evaluated and were similar to previous reports. Tazobactam M1 metabolite maximum plasma concentration increased as renal function declined. The terminal elimination half-life and area under the plasma concentration-time curve of the tazobactam M1 metabolite increased as renal function declined. The mean rate of recovery of the tazobactam M1 metabolite in hemodialysate during a 3- to 4.2-hour HD session 1 hour after the i.v. infusion of piperacillin/tazobactam was 25.3%. However, when HD was performed at 36-48 hours after the i.v. infusion, 57.6% of the tazobactam dose was recovered as M1 metabolite, suggesting further conversion of tazobactam to M1 metabolite. Peritoneal dialysis removed 15.8% (n = 2) of the tazobactam dose as the M1 metabolite. Using a dose of 3 g of piperacillin/0.375 g of tazobactam, the predicted maximum steady-state plasma concentrations of the tazobactam M1 metabolite are 14.6 micrograms/mL, 34.8 micrograms/mL, and 48.8 micrograms/mL for subjects with ClCR 20-40 mL/min (every 6 hour dosing), ClCR < 20 mL/min (every 8 hour dosing), and on CAPD (every 12 hour dosing), respectively.

Adult↗
PubMed1994

Operational characteristics of radiology groups in the United States in 1992.

PURPOSE: To determine the operational characteristics of radiology groups in the United States in 1992. MATERIALS AND METHODS: The American College of Radiology surveyed a stratified random sample of 695 radiology groups, including academic departments, units in multispecialty groups, and staff of government facilities. After intensive follow-up, a 69% response rate was achieved for in-scope groups. The responses were weighted to show what findings would have been if all radiology groups in the country had responded. RESULTS: Thirteen percent of groups practiced in a university or teaching hospital; 59%, in a nonprofit hospital; and 18%, in a proprietary hospital; 42% routinely read images obtained by other practices; and 15% were involved with mobile vans. Radiologists in diagnostic-only practices averaged 11,100 procedures per year per full-time equivalent. However, the average was about one-third lower in office-only practices and primarily academic practices. Most groups had no female radiologists. CONCLUSION: Workload data show a great deal of variability and means should not be taken as standards.

Female↗
PubMed1994

Basic characteristics of radiology groups in the United States: results of a 1991-1992 census.

OBJECTIVE: The American College of Radiology (ACR), the principal professional organization of United States radiologists, receives numerous requests for information on the characteristics of radiology groups. This report describes the basic characteristics of radiology groups in the United States. We defined radiology groups as any practice with two or more radiologists or radiation oncologists, including academic departments, units in multispecialty groups, and staff of government facilities. MATERIALS AND METHODS: To collect basic information on radiology groups, the ACR conducted a mail census of all identified radiology groups in the United States during late 1991 and early 1992. Follow-up was conducted by mail and telephone. To make the responses accurately representative of all radiology groups, we weighted the approximately 2000 responses to correspond to known control totals for the number of groups of each of seven size categories in each of the four census regions (Northeast, Midwest, South, and West). These control totals were obtained from the ACR's 1990 Manpower Survey, which showed a total of approximately 3200 radiology groups. RESULTS: Approximately one fourth of all groups have two radiologists, one fourth have three or four radiologists, one fourth have five to seven radiologists, and one fourth have eight or more radiologists. Academic groups were relatively large; almost 50% had 11 or more radiologists. Nonmetropolitan areas had very few large groups, and metropolitan center cities had relatively few small groups. Ninety-two percent of all groups practiced at hospitals, and 73% of all groups practiced at nonhospital offices or centers. The median number of practice sites for all groups was three, including both hospital and nonhospital sites. Eighty-eight percent of all groups provided diagnostic radiology services, 23% provided radiation oncology, 12% offered both, and 11% were oncology-only groups. Relatively many academic groups (25%) were oncology-only groups; very few radiology groups (2%) in multispecialty practices were oncology-only groups. The diagnostic radiology techniques available from the largest percentages of groups were general radiography (plain film), sonography, mammography, and CT. One eighth of academic groups that provided diagnostic services did not report providing mammography, compared with only a few percent of all groups in the United States that provided diagnostic services. CONCLUSION: Half of all groups have two to four radiologists, and this has not changed since at least 1986. A substantial percentage of groups that perform diagnostic radiology do not provide MR, interventional, or nuclear medicine services. This is particularly true of relatively small groups. These characteristics may become the source of some problems as managed care becomes more prominent and larger groups, offering a full range of services and practicing at several sites, are favored by managed care organizations that seek to contract with one group for all their radiology services.

Data Collection↗
PubMed1993

Sexual arousal in diabetic females: physiological and self-report measures.

Diabetes mellitus, a major health problem afflicting 500,000 Americans each year, is a leading cause of male erectile difficulties. Diabetic women may be susceptible to a similar diabetic pathogenesis for sexual problems but information about the effect of diabetes on female sexual response is sparse and conflicting. Past research has been based upon self-report measures, a methodology flawed by susceptibility to response bias. Whether diabetic women differed from a matched nondiabetic control group in their physiological as well as subjective response to erotic stimulus exposures was investigated. Vaginal photoplethysmographic measures of capillary engorgement were taken while subjects individually viewed counterbalanced erotic and non-erotic videotape presentations. Graphically and statistically analyzed results indicated that diabetic women demonstrated significantly less physiological arousal to erotic stimuli than controls, whereas their subjective responses were comparable. These objective, physiological findings support and extend previous subjectively based research which found potential diabetes-related sexual dysfunction in female diabetics. The groups did not differ, however, in the reported occurrence of sexual difficulties.

Adolescent↗