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N Zafar

Publications and source records attributed to N Zafar.

At least 19 recordsLinked to original sources
PubMed2005

Switchability of neoral and equoral according to Food and Drug Administration rules and regulations.

According to the US Food and Drug Administration (FDA), if a drug product contains a drug substance that is chemically identical and is delivered to the site of action at the same rate and extent as another drug product, then it is equivalent and can be substituted (switchable) for that drug product. Methods used to define bioequivalence as stated by the FDA rules (FDA 21 CFR 320, 24) are (1) pharmacokinetic (PK) studies in healthy volunteers, (2) comparative clinical trials, and (3) pharmacodynamic (PD) studies (bioactivity). We evaluated the switchability of Equoral (IVAX-USA) with Neoral (Novartis Switzerland using all FDA rules. In a single oral dose, we undertook a comparative bioavailability study of Equoral (IVAX, USA) Neoral (Novartis, USA), and Neoral (Novartis UK). The pharmacokinetics of Equoral and Neoral were determined with blood levels at 0, 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 10, 12, 16, 24, 30, 36, 42, and 48 hours. The area under curve (AUC), AUC extrapolated to infinity (AUC0-inf), rate of absorption (Tmax), extent of absorption (Cmax), half time (t1/2) of Equoral and Neoral were all within the 90% confidence interval of 80% to 125% boundaries. A comparative multinational multicenter clinical trial in stable renal transplant patients included 70 patients (22 women and 48 men) of mean age of 33 years (range, 26 to 43) was performed in Turkey, Lebanon, and Pakistan. In this study the ratios of LSM and the 90% confidence intervals for the Nontransformed/Parameters (AUC0-t, AUCinf, Tmax, and Cmax) of Equoral and Neoral SGC were 98% and 95%, respectively, which are within the 80% to 125% FDA acceptance range. For immunosuppressive drugs, the site of action is the lymphocyte and the measurable response is the decrease in lymphocyte count caused by the relative concentration of the drug in the lymphocyte. In a controlled switch, fixed-dose study, both Equoral and Neoral achieved the same concentration in the lymphocytes and caused the same degree of lymphocyte count reduction. The results of the testing (bioavailability-bioequivalence, clinical studies, and pharmacodynamic-bioactivity) required by FDA for interchangeability ("switchability") of immunosuppressive agents suggests that Neoral and Equoral are switchable.

Adult↗
PubMed2003

Genome of Geobacter sulfurreducens: metal reduction in subsurface environments.

The complete genome sequence of Geobacter sulfurreducens, a delta-proteobacterium, reveals unsuspected capabilities, including evidence of aerobic metabolism, one-carbon and complex carbon metabolism, motility, and chemotactic behavior. These characteristics, coupled with the possession of many two-component sensors and many c-type cytochromes, reveal an ability to create alternative, redundant, electron transport networks and offer insights into the process of metal ion reduction in subsurface environments. As well as playing roles in the global cycling of metals and carbon, this organism clearly has the potential for use in bioremediation of radioactive metals and in the generation of electricity.

Acetates↗
PubMed2001

Improving survival of vulnerable infants increases neonatal intensive care unit nosocomial infection rate.

OBJECTIVE: To determine the factors associated with an increasing rate of nosocomial infections in infants with very low birth weights. METHODS: Retrospective review of clinical and nosocomial infection databases for all infants with birth weights of 1500 g or less admitted to an academic neonatal intensive care unit between January 1, 1991, and December 31, 1997 (N = 1184). Two study periods were compared: 1991-1995 and 1996-1997. RESULTS: Among the 1085 infants who survived beyond 48 hours, the proportion who developed nosocomial infections increased from 22% to 31% (P =.001) and the infection rate increased from 0.5 to 0.8 per 100 patient-days (P<.001) during the period from 1996 to 1997. In that same period, the median duration of indwelling vascular access increased from 10 to 16 days (P<.001), and the median duration of mechanical ventilation increased from 7 to 12 days (P<.001). Although the device-specific rate of bloodstream or respiratory infections did not change, the increase in infections was directly attributable to the increasing proportion of infants who required these devices. In both study periods, the peak incidence of initial infection occurred between 10 and 20 days of age. For the entire sample, proportional hazard models identified birth weight, duration of vascular access, and postnatal corticosteroid exposure as significant contributors to the risk of infection. CONCLUSIONS: The increasing number of technology-dependent infants was the primary determinant in the increase of nosocomial infections. Because these infections occur in a small proportion of infants, understanding the host factors that contribute to this vulnerability is necessary to decrease nosocomial infections in neonatal intensive care units.

Catheterization, Central Venous↗
PubMed2001

Comparisons of gene colinearity in genomes using GeneOrder2.0.

Comparative genomics is enhanced by data mining the rapidly expanding DNA sequence databases. Because of the immense amount of data, computational tools and methods are needed to augment traditional manual visualizations and manipulations of these data. GeneOrder2.0, a Java-based interactive software programme, organizes genome sequence data into tabular and graphical visualizations of the extent of colinearity of genes between any two chromosome genomes of < or =250 kilobases. Both GenBank and proprietary data can be analyzed with this tool.

Computational Biology↗
PubMed1997

Embryonal adenoma of the kidney: a report of two cases.

Embryonal (metanephric) adenoma of the kidney, like Wilms' tumor, exhibits small monomorphic, blue cells arranged as vague, tubular rosettes. Unlike Wilms' tumor, which requires chemotherapy or multi-modality therapy for optimal management, the available evidence indicates that embryonal adenoma is most likely cured by simple enucleation or nephrectomy. Two women, age 54 (Case 1) and 78 (Case 2), respectively, underwent needle biopsy for a radiologically well circumscribed renal lesion with associated hematuria. The cellular smears contained vague rosette-like arrangement of small, blue cells with scant cytoplasm and evenly distributed, fine, nuclear chromatin. In cell blocks, these cells were arranged as compact, primitive, tubular rosettes or rare, moresolid clusters. Assuming that the absence of undifferentiated blastema and primitive glomeruli represented a sampling error, a diagnosis suggesting of Wilms' tumor was made in Case 1. At nephrectomy, despite extensive sampling, the typical triphasic Wilms' morphology and anaplastic or necrotic areas were not seen. In the presence of architectural monotony, the diagnosis in Case 1 was amended to embryonal adenoma. Case 2 was cytologically diagnosed as embryonal adenoma of the kidney and is being followed conservatively. In our opinion, the presence of monotypic architecture at cytology/histology is very helpful in differentiating renal embryonal (metanephric) adenoma from Wilms' tumor.

Adenoma↗
PubMed1997

Prediction of renal function recovery in obstructive renal failure due to stones.

Two hundred and thirty-nine patients with renal and ureteric calculi associated with renal failure were evaluated for recovery potential before definitive surgery. Ultrasonography was carried out pre-operatively in all, followed by percutaneous nephrostomy (PCN) as an initial management before definitive surgery. Diethylene triamine penta acetic acid (DTPA) scan was done in 125 patients after percutaneous nephrostomy, findings of pre- operative DTPA scan were correlated with post-operative drop in serum creatinine. Urine pH, urine Na+, initial diuresis, creatinine clearance and serum creatinine were measured serially after 24 hours and then every week for 6 weeks. Patients were re-evaluated with serum creatinine after 3 months of surgery. Ultrasonography was found to be reliable in predicting future recovery of renal functions in 76.5% cases and true obstruction of shorter duration (F4-group) on DTPA scan in 81.9% cases. Urine pH of 6 or less, post-PCN diuresis and natriuresis were good prognostic indicators. PCN was found to be most reliable method of predicting future recovery of renal function after relief of obstruction with 97.8% accuracy.

Adult↗