PubMed Health⌕ Search

Biomedical subjects

L Shah

Publications and source records attributed to L Shah.

14 recordsLinked to original sources

Marie Stopes Society, Pakistan: 1000 cases of quinacrine sterilization (QS).

OBJECTIVES: To evaluate the safety, efficacy and acceptability of QS in Karachi, Pakistan. METHODS: 1000 women who had chosen sterilization during the 4-year period 1994 to 1997 inclusive were offered QS at both stationary clinics and in a mobile van at 23 sites in the outskirts of Karachi. The protocol involved transcervical insertion to the uterine fundus of 252 mg quinacrine in 7 pellets and 55 mg of ibuprofen in 3 pellets through an IUD inserter, during the proliferative phase of the menstrual cycle. Two doses were administered one month apart. A temporary method of contraception was provided for 3 cycles, usually DMPA. Follow-up was scheduled: monthly for 3 months, quarterly for 1 year and then every 6 months for 4 years. RESULTS: The crude pregnancy rate after 4 years was 2.0%. Minor complications and complaints were reported by 59% of the patients. There was one ectopic pregnancy and no major complications. CONCLUSIONS: QS was found to be safe and effective and has become the most popular method of sterilization in our area of Pakistan.

Ambulatory Care Facilities↗

Long acting beta-agonists versus theophylline for maintenance treatment of asthma.

BACKGROUND: Theophylline and long acting beta2-agonists are bronchodilators used for the management of persistent asthma symptoms, especially nocturnal asthma. They represent different classes of drug with differing side-effect profiles. OBJECTIVES: To assess the comparative efficacy, safety and side-effects of long-acting beta-agonists and theophylline in the maintenance treatment of asthma. SEARCH STRATEGY: Randomised, controlled trials (RCTs) were identified using the Cochrane Airways Group register. The register was searched using the following terms: asthma and theophylline and long acting beta-agonist or formoterol or foradile or eformoterol or salmeterol or bambuterol or bitolterol. Titles and abstracts were then screened to identify potentially relevant studies. The bibliography of each RCT was searched for additional RCTs. Authors of identified RCTs were contacted for other relevant published and unpublished studies. SELECTION CRITERIA: All included studies were RCTs involving adults and children with clinical evidence of asthma. These studies must have compared oral sustained release and/or dose adjusted theophylline with an inhaled long-acting beta-agonist. DATA COLLECTION AND ANALYSIS: Potentially relevant trials, identified by screening titles and/or abstracts, were obtained. Two reviewers independently assessed full text versions of these trials to decided whether the trial should be included in the review, and assessed its methodological quality. Where there was disagreement between reviewers, this was resolved by consensus, or reference to a third party. Data were extracted by two independent reviewers. Inter-rater reliability was assessed by simple agreement. Study authors were contacted to clarify randomisation methods, provide missing data, verify the data extracted and identify unpublished studies. Relevant pharmaceutical manufacturers were also contacted. MAIN RESULTS: Six trials met the inclusion criteria. Five used salmeterol and one, biltoterol. They were of varying quality. There was a trend for salmeterol to improve FEV1 more than theophylline in three studies and salmeterol use was associated with more symptom free nights. Bitolterol, used in only one study, was reported to be less effective than theophylline. Subjects taking salmeterol experienced fewer adverse events than those using theophylline (Relative Risk 0.38; 95%Confidence Intervals 0.25, 0.57). Significant reductions were reported for central nervous system adverse events (Relative Risk 0.51; 95%Confidence Intervals 0.30, 0.88) and gastrointestinal adverse events (Relative Risk 0.32; 95%Confidence Intervals 0.17, 0.59). REVIEWER'S CONCLUSIONS: Salmeterol may be more effective than theophylline in reducing asthma symptoms including night waking and improving lung function. More adverse events occurred in subjects using theophylline when compared to salmeterol.

Adrenergic beta-Agonists↗

Comparison of analytical methods for quantitation of isolated porcine hepatocyte yields.

As cell-based therapies receive approval for clinical evaluation and use, the development of reliable methods to quantify cell number and control the dose of therapy delivered is becoming increasingly important. An example is the determination of the number and volume of primary porcine hepatocytes used in an extracorporeal treatment for patients with liver disease. Conventional cell counting using optical microscopy was compared against two alternate methods to quantify isolated porcine hepatocytes: (1) automated cell counting using a commercially available particle characterization instrument, and (2) quantitation by cell mass. Methods were compared based on accuracy, precision, specificity, linear range, and ruggedness. The automated method delivered substantially improved accuracy, precision, and ruggedness when compared to the conventional optical method. It also provided valuable information about the size distribution of cell preparations, which often contained clumps of cells, and showed that processing steps such as cryopreservation can alter the size characteristics of a cell population. The automated method was also faster, and was well suited to use in a commercial manufacturing process. The mass-based method was simple and inexpensive, but suffered from nonlinearity at low cell concentrations. Automated cell quantitation using a commercially available particle characterization instrument proved to be the preferred method for obtaining accurate and consistent porcine hepatocyte counts in a timely manner.

Animals↗

Isolation of primitive human hematopoietic progenitors on the basis of aldehyde dehydrogenase activity.

Because hematopoietic stem cells are rich in aldehyde dehydrogenase (ALDH) activity, we developed a fluorescent substrate for ALDH, termed BODIPY aminoacetaldehyde (BAAA), and tested its potential for isolating primitive human hematopoietic cells. A population of cells with low orthogonal light scattering and bright fluorescence intensity (SSC(lo)ALDH(br) cells) could be readily fractionated from human umbilical cord blood cells costained with BAAA and the multidrug-resistance inhibitor verapamil. The SSC(lo)ALDH(br) population was depleted of lineage-committed cells, 40-90% pure for CD34(+)CD38(lo/-) cells, and enriched 50- to 100-fold for primitive hematopoietic progenitors detected in short- and long-term culture analyses. Together, these observations indicate that fractionating human hematopoietic stem cells on the basis of ALDH activity using BAAA is an effective method for isolating primitive human hematopoietic progenitors. This technique may be useful for isolating stem cells from other tissues as well.

Aldehyde Dehydrogenase↗

Prenatal diagnosis of sirenomelia with bilateral hydrocephalus: report of a previously undocumented form of VACTERL-H association.

Sirenomelia represents a severe developmental field defect of the posterior axis caudal blastema, resulting in partial or complete fusion of the lower limb buds. The VATER association is a combination of morphological defects including vertebral defects, anal atresia, tracheoesophageal fistula, esophageal atresia, radial and renal anomalies. The VACTERL-H association is a rare expanded form of the VATER association that includes cardiac defects, limb defects, and hydrocephalus. It has been suggested that the VATER association may represent a less severe form of sirenomelia. In this report, we document a case in which prenatal ultrasonography detected simultaneously occurring sirenomelia and hydrocephalus. Postmortem radiography and autopsy findings confirmed the prenatal diagnosis. To our knowledge, this is the first report of prenatal diagnosis of a fetus with these two abnormalities. This report supports the hypothesis that VATER association, VACTERL-H association, and sirenomelia may represent pathophysiologically related entities.

Adult↗

The effect of edrophonium chloride on muscle balance in normal subjects and those with nonmyasthenic strabismus.

Because the Lancaster red-green test and the Hess screen are not widely used by most ophthalmologists, we used the alternate prism-cover test to study the effect of intravenous edrophonium chloride (Tensilon) on the ocular alignment of 30 normal subjects and 14 individuals with nonmyasthenic strabismus. After measurement of their baseline phorias and tropias, patients received an intravenous injection of Tensilon via the incremental dose technique until autonomic effects of the drug were noted or until 10 mg was administered. Another set of measurements of muscle balance was taken immediately postinjection and 2 and 5 min later. Apart from a small increase (mean, 2 prism dipoters; p = 0.004) in their exophoria at near, normal subjects exhibited no significant change in their phorias after Tensilon injection. One third to one half of the nonmyasthenic strabismics, however, showed a change in their vertical deviation after Tensilon (46% at distance and 38% at near), with the majority of them increasing their angle of squint. These changes were small (mean, 1.7 prism diopters; maximum, 5 prism diopters). In only one case did reversal of the direction of deviation occur. Tensilon produces a statistically significant increase in near exophorias of normal subjects and in vertical distance deviations of nonmyasthenic strabismics. These changes, however, are clinically insignificant and should not be considered to constitute a positive Tensilon test.

Adolescent↗

Impact of an inner-city, hospital-based preterm prevention program on preterm births in twin gestation.

The objective of this study was to determine the impact of an inner-city, hospital-based preterm-birth prevention program on the outcome of twin pregnancies. A retrospective study of delivery outcomes from 1985 to 1992 of eligible consecutive twin deliveries that were > or = 20 weeks' gestation compared two inner-city hospitals in the Bronx, New York: one with a preterm prevention program for twin births and a comparable site offering conventional prenatal care. A group of patients receiving no prenatal care was also included. Outcomes were evaluated by prenatal-care site, except for those who received no prenatal care and delivered at either site. Data were analyzed by chi-square analysis and analysis of variance. Of the 377 twin pregnancies, 330 pregnancies were eligible deliveries. One hundred thirty-four women received prenatal care from the preterm prevention program, 161 received conventional prenatal care at a comparable site, and 35 received no prenatal care. Maternal age, parity, and mode of delivery were similar in the two delivery sites. There was an increased incidence of complications in the no-prenatal-care group compared with the groups who received the preterm prevention or conventional prenatal care. The percentage of low-birth-weight (< 2500 g) and very-low-birth-weight (< 1000 g) infants was similar in the preterm prevention and the conventional care groups. The percentage of extremely low-birth-weight (< 1000 g) infants was significantly lower in twin births of the preterm prevention site (9.7%) and the conventional site (11.3%) compared with the no-prenatal-care group (28.6%) (P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Enamel rehardening with cheese in irradiated patients.

Radiotherapy of head and neck malignancies results in severe xerostomia which induces radiation caries. Hard cheese has potent anti-cariogenic effects, even with minimal salivary gland function. Eight patients irradiated for neck cancer volunteered for this study. The saliva flow rate varied between 0.0-0.15 ml/minute. In vitro etched enamel slabs, prepared from human teeth, were exposed intraorally to parafilm stimulated salivary secretion for 5 minutes or, alternatively, to cheese compounds and saliva due to masticating 20 gm hard cheese for 5 minutes. Microhardness measurements were carried out on the enamel surface at start (baseline), after etching and after rehardening. Stimulated saliva or cheese compounds and saliva, due to mastication, induced rehardening of surface enamel in both, non-irradiated and irradiated subjects. The rehardening was significantly increased in the irradiated group consuming cheese as compared to rehardening by stimulated saliva only and not significantly less of that achieved in non-irradiated subjects. Rehardening achieved with stimulated saliva in irradiated patients was of a borderline-significant lower degree in comparison to non-irradiated subjects. The reduced rehardening capacity of a decreased saliva flow in irradiated patients may be complemented by cheese compounds. For xerostomic patients, hard cheese consumption may be regarded as effective to keep initial caries under control.

Cariostatic Agents↗

Prevalence of microalbuminuria in diabetic subjects.

Total 193 diabetic patients were investigated to assess the prevalence of microalbuminuria. Urinary albumin excretion rate (UAER) was measured by radioimmunoassay (RIA) on 3 hours urine samples. The prevalence of microalbuminuria (UAER) > 15 micrograms/min was 41%. Microalbuminuria was commonly observed in patients having diabetes for more than 5 years. A significant correlation was found between duration of diabetes and microalbuminuria (p < 0.01). Glycemic control (fasting and postprandial blood sugar) did not show any correlation with UAER, whereas blood urea (r.39, p < 0.01), creatinine (r.26, p < 0.05) and chloride (r.24, p < 0.05) were positively correlated. A significant correlation was found between raised blood pressure and UAER (p < 0.01).

Adult↗

Association of Haemophilus ducreyi with cell-culture lines.

The association of Haemophilus ducreyi with epithelial cell cultures was studied by light microscopy, electronmicroscopy and viable counts. Associated organisms were engulfed by epithelial cells and sequestered from the cell-surface environment. Large numbers of organisms within epithelial cells appeared to induce cell lysis and release of H. ducreyi. Such a mechanism occurring in vivo may assist H. ducreyi to evade the bactericidal action of polymorphonuclear leucocytes and may explain some of the tissue damage seen in genital ulcers caused by H. ducreyi.

Animals↗

A model for the mechanism of optic nerve sheath fenestration.

The mechanism by which optic nerve sheath fenestration relieves papilledema associated with increased intracranial pressure has not been clearly defined. A model was constructed to determine if the induction of fluid flow along the nerve sheath and through the fenestration could account for a reduction in pressure around the optic nerve, as might be expected according to Bernoulli's equation of fluid dynamics. The model states that as the velocity of a fluid increases, the pressure it exerts decreases. The model simulated fluid spaces corresponding to the intracranial vault, chiasm, and optic nerves. The unfenestrated model showed direct transmission of elevated intracranial pressure to the nerves, consistent with the production of papilledema. When one nerve was fenestrated, fluid flow along the nerve was initiated and pressure in that nerve sheath dropped substantially. In addition, pressure in the unfenestrated sheath dropped due to fluid communication across the chiasm. These lower intrasheath pressures were consistent with the bilateral resolution of papilledema after unilateral fenestration. The reduced intrasheath pressures persisted even when the intracranial pressure was again elevated to pathologic levels as long as active fluid flow continued along the nerve sheaths. Thus, induction of cerebrospinal fluid flow along the optic nerve sheath by fenestration appears to locally reduce the pressure around the optic nerve, in spite of persistently elevated intracranial pressure. This is in accordance with what would be predicted by Bernoulli's equation.

Cerebrospinal Fluid↗

Antitoxin activity of human polymorphonuclear leucocytes.

Human polymorphonuclear leucocytes (PMNL) inactivate Clostridium difficile cytotoxin and C. perfringens phospholipase C, but not C. perfringens enterotoxin. Both whole cells and sonicated suspensions possess activity, but mononuclear cell fractions of peripheral blood do not. Antitoxin activity closely correlates with cell concentration. The highest cell concentrations tested completely inactivated C. difficile cytotoxin by 2 min. Sucrose density gradient fractionation of PMNL showed antitoxin activity to be associated with myeloperoxidase, locating it in the primary or azurophil granules. Toxin inactivation was prevented by protease inhibitors suggesting that it is due to one of the neutral proteases present in these granules. PMNL are more active against C. difficile cytotoxin than purified chymotrypsin. PMNL may be a primary defence against certain bacterial exotoxins.

Bacterial Toxins↗

Labor and delivery in nulliparous women who present with an unengaged fetal head.

OBJECTIVE: We assessed the relation of fetal station in early labor to subsequent patterns of dilation and descent and to the probability of cesarean delivery. STUDY DESIGN: We evaluated 132 nulliparous women who were in spontaneous latent-phase labor with singleton, vertex-presenting, term fetuses. For each participant, pertinent variables relating to labor characteristics and mode of delivery and newborn characteristics were recorded. Labor curves were drawn and analyzed. RESULTS: Of the 132 participants, 29 (22%) presented with an engaged fetal head, and 103 (78%) presented with an unengaged fetal head. In the unengaged group, 15 (11%) presented with a floating fetal head (-3 station or above), and 88 (67%) presented with a dipping fetal head (-2 or -1 station). A floating head in latent-phase labor conferred a longer second stage (p = 0.02), a trend to more active-phase labor disorders (p = 0.06), and a greater risk of cesarean delivery. Overall, 12 patients (9%) underwent primary cesarean section: 2 (6.9%) from the engaged group, 6 (6.8%) from the dipping group, and 4 (27%) from the floating group (p = 0.042). CONCLUSION: Most nulliparous women in this study presented in labor with an unengaged fetal head. Those with a floating fetal head demonstrated higher rates of cesarean section than those with dipping or engaged heads in early labor.

Adolescent↗