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S Bansal

Publications and source records attributed to S Bansal.

At least 19 recordsLinked to original sources
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

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↗
PubMed1993

Primary sequence and location of the idiotopes of V-88, a DNA-binding monoclonal autoantibody, determined by idiotope scanning with synthetic peptides on pins.

In this study, the primary sequence and location of the idiotopes of monoclonal antibody (mAb) V-88 have been examined. V-88 was derived from an adult (NZB x NZW)F1 mouse, has been partially defined previously with polyclonal anti-idiotype antisera, and is a member of the 16/6 idiotype (Id) family. From the inferred primary amino acid sequence of the antibody, sets of hexapeptides, overlapping by five residues, were synthesized on pins and used to scan the expression of epitopes (idiotopes) in the V regions of the light and heavy chains. A heterologous rabbit antiserum raised against the native antibody V-88, and absorbed to make it idiotype specific, was found to react with eight major epitopes distributed between the VH and VL regions. Half of these determinants mapped to the complementarity determining regions, with the others in framework sequences. Thus, the idiotype of antibody V-88 comprises, at least in part, continuous linear idiotopes in both hypervariable and framework areas. The process of absorbing the anti-idiotype antiserum on normal mouse immunoglobulin removed much of the background antibody activity against V region peptides, but left the activity against the dominant idiotopes. The sequence of a major idiotope, VATISG, in the FW2/CDR2 VH region is homologous to sequences of human antibodies that express the 16/6 idiotype, suggesting that Id.16/6 is at least in part defined by this region of the antibody. The same VH area is also homologous to sequences in bacterial and mammalian heat-shock proteins (hsp60-65). Thus there may be a functional link through idiotype connections, especially those involving Id.16/6, between anti-bacterial responses and production of autoantibodies, and some bacterial antigens may function indirectly as superantigens for B cells.

Amino Acid Sequence↗
PubMed1992

A peptide from Schumanniophyton magnificum with anti-cobra venom activity.

Using the chick biventer cervicis preparation as a bioassay for antivenom activity, a peptide has been isolated from the aqueous extract of the bark of Schumanniophyton magnificum. The peptide was isolated and purified by a combination of reverse-phase and exclusion column chromatography, preparative TLC, and HPLC. The peptide has a relative molecular mass of about 6000 daltons and is similar in amino acid composition to the cardiotoxins present in snake venom. The isolated peptide showed dose-related inhibitions of the effects of cardiotoxin and total venom of cobra species using the chick biventer cervicis preparation.

Animals↗
PubMed1992

Operational, professional, and business characteristics of radiology groups in the United States.

To learn the main operational, professional, and business characteristics of U.S. radiology group practices, researchers at the American College of Radiology surveyed these groups. Major findings included the following: Approximately 30% of groups provide only diagnostic radiologic services, a similar percentage provides only radiation therapy for oncologic patients, and the remainder provides both types of services. Forty-one percent of groups practice only in hospitals, 11% practice only in an office, and 48% practice in both settings. Diagnostic-only practices average 10,000-12,000 procedures per full-time equivalent radiologist per year. Groups typically require new members to be part of the group for almost 3 years before they become full partners. Formal call schedules are nearly universal among radiology groups. Groups are becoming increasingly involved with health maintenance organizations and other "alternative delivery systems," but fee-for-service remains by far the dominant source of groups' revenue. Most studied characteristics of groups are changing relatively slowly, and trends are generally toward increasing formalization of arrangements.

Age Factors↗
PubMed1992

Hospital and office practices of radiology groups.

To obtain information on the characteristics and practices of radiology groups in the United States, the American College of Radiology conducted a group practice survey in 1989; this report presents the main survey findings about the office and hospital practices of such groups. A questionnaire and one follow-up were mailed to all 2,591 radiology groups in the United States. Responses were weighted to reflect all groups. Hospital practices averaged 0.7 diagnostic radiologic procedures (including outpatient procedures) per patient day, with little variation by hospital type. Magnetic resonance (MR) imaging and angioplasty procedures were concentrated in teaching hospitals, but this was not true of other sophisticated procedures such as computed tomography and nuclear medicine. Offices averaged 15,000 diagnostic examinations annually, with less variation than expected according to group size. In both hospitals and offices, more than 90% of technologists were registered. Outsiders (most often, referring physicians and hospitals) had a financial interest in half of all offices. MR imaging and mammography grew faster than any other examinations, but only 44% of hospital practices accepted nonreferred patients for mammography.

Ambulatory Care↗
PubMed1991

Volunteer bias in a study of male alcoholics' sexual behavior.

Studies on sexual behavior frequently require that subject volunteers engage in intrusive/sensitive assessment procedures. While earlier investigators have found that these demands may result in volunteer bias (volunteers differing from nonvolunteers), these studies were limited to nonclinical samples. The present study involved 182 males admitted to an inpatient alcoholism rehabilitation program. Those patients who volunteered to participate in an intrusive study examining sexual functioning were dissimilar to nonvolunteers. Compared to nonvolunteers, volunteers reported a greater interest in sex, less satisfaction with sex, more concerns about sexual functioning, a greater incidence of premature ejaculation, and a greater incidence of negative sexual experience. Volunteers also had a higher MAST score, used outpatient substance-abuse counseling more often, and more frequently had a diagnosis of cocaine/amphetamine dependence and cannabis dependence. These differences between volunteers and nonvolunteers suggest a need to use caution when generalizing the results of similar studies to the overall population. Procedures that may help to minimize volunteer bias are offered.

Adult↗
PubMed1991

Possible hypothalamic impotence. Male counterpart to hypothalamic amenorrhea?

Twenty-one men with erectile complaints who were found to have a low level of serum testosterone without a reciprocal elevation of the serum levels of luteinizing hormone were evaluated to identify whether the defect was of hypothalamic or of pituitary origin. Patients underwent a luteinizing hormone (LH)-follicle-stimulating hormone (FSH)-releasing hormone stimulation test that showed a normal but sluggish increase in LH and FSH levels, thus ruling out a pituitary defect and suggesting a suprapituitary abnormality. This was confirmed when, in response to clomiphene, patients had a normal increase in gonadotropin and testosterone levels. Although the basal as well as clomiphene and gonadotropin releasing hormone-stimulated levels of total testosterone and gonadotropins were identical in men less than and more than fifty years old, the elevation of free testosterone levels in response to clomiphene was higher in patients younger than fifty. This suggested that although the primary abnormality found in these patients is altered secretion of gonadotropin hormone-releasing hormone from the hypothalamus, an age-related decline in the responsivity of Leydig cells to LH may make it more manifest in older patients. Elevation of testosterone levels from a subnormal to a normal range in response to clomiphene administered for seven days suggests that the defect is functional and reversible and that the drug may be useful in treatment of sexual dysfunction in this group of patients.

Aging↗
PubMed1991

The volume and cost of radiologic services in the United States in 1990.

Knowing the total number of radiologic services provided in the United States and their cost is important. This information can, for example, indicate the opportunities available to a radiology practice considering opening a new office or show whether high-technology radiology is, as is widely assumed, an important factor in United States health costs. However, neither the total number of procedures nor their cost is known. We developed two largely independent estimates of each total (one based principally on surveys of radiologists, the other on Medicare data) to cross-validate the estimates and provide an indication of their uncertainty. We estimate that 260-330 million radiologic procedures were performed in the United States in 1990 (including both diagnostic and therapeutic procedures and radiologic procedures performed by nonradiologists) and that payments for these services totaled $19 to $22 billion (including payments for technical components in the hospital setting). This total was approximately 3.5% of national spending on personal health care; high-technology radiology totaled less than half of this amount. The procedures numbered 1.0-1.3 per capita annually, an increase of some 10-40% since 1980. Of the spending total, $10 to $12 billion was paid to physician practices, with a substantial portion of this amount going ultimately to practice expenses, particularly in the office setting. Our results suggest that spending on high-technology radiology is too small to be a major explanation for the current level of health costs in the United States.

Costs and Cost Analysis↗
PubMed1989

A new TSH assay. Just another technique or a useful test?

The immunoradiometric assay is a sensitive test for diagnosing thyroid dysfunction. It permits greater accuracy by measuring response of thyrotropin-producing cells of the pituitary to thyroxine (T4) as opposed to comparing circulating T4 to a range of values from healthy controls. The assay allows improved precision in establishing replacement and suppressive doses of hormone for thyroid disease.

Humans↗