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Manish Gupta

Publications and source records attributed to Manish Gupta.

9 recordsLinked to original sources
PubMed2005

Cavity-enhanced quantum-cascade laser-based instrument for carbon monoxide measurements.

An autonomous instrument based on off-axis integrated cavity output spectroscopy has been developed and successfully deployed for measurements of carbon monoxide in the troposphere and tropopause onboard a NASA DC-8 aircraft. The instrument (Carbon Monoxide Gas Analyzer) consists of a measurement cell comprised of two high-reflectivity mirrors, a continuous-wave quantum-cascade laser, gas sampling system, control and data-acquisition electronics, and data-analysis software. CO measurements were determined from high-resolution CO absorption line shapes obtained by tuning the laser wavelength over the R(7) transition of the fundamental vibration band near 2172.8 cm(-1). The instrument reports CO mixing ratio (mole fraction) at a 1-Hz rate based on measured absorption, gas temperature, and pressure using Beer's Law. During several flights in May-June 2004 and January 2005 that reached altitudes of 41,000 ft (12.5 km), the instrument recorded CO values with a precision of 0.2 ppbv (1-s averaging time) and an accuracy limited by the reference CO gas cylinder (uncertainty < 1.0%). Despite moderate turbulence and measurements of particulate-laden airflows, the instrument operated consistently and did not require any maintenance, mirror cleaning, or optical realignment during the flights.

Journal Article↗
PubMed2005

The clinical pharmacokinetics of phosphodiesterase-5 inhibitors for erectile dysfunction.

Differences in the clinical pharmacology of the 3 currently available oral phosphodiesterase-5 (PDE5) inhibitors, sildenafil, vardenafil, and tadalafil, are largely determined by their clinical pharmacokinetics as well as their PDE inhibitory activity profile. This review comparatively discusses the major characteristics of the pharmacokinetic profile of all 3 PDE5 inhibitors, including bioavailability and rate of absorption, Biopharmaceutical Classification System categorization, elimination mechanisms, and metabolic profile including active metabolites, as well as the drug-drug interaction potential and modification of pharmacokinetic properties under selected physiologic and pathophysiologic conditions. The review is aimed at providing comparative clinical pharmacology data to allow for scientifically rational, evidence-based prescribing and dosing decisions regarding the clinical use of these medications for the treatment of erectile dysfunction.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2004

Quantitative detection of singlet O2 by cavity-enhanced absorption.

A method for the practical determination of the absolute concentration of single (a1delta(g)) oxygen is discussed. The method is based on sensitive off-axis integrated-cavity-output spectroscopy (ICOS). Off-axis ICOS allows narrowband, continuous-wave lasers to be used in conjunction with optical cavities to record sensitive absorption measurements. The details of the method as well as spectroscopic data confirming the first observation of the (1, 0) band of the b1sigma(g)(+) - a1delta(g) Noxon system are presented. The absolute transition probabilities for the b1sigma(g)(+) - a1delta(g) Noxon system, which are not known precisely from experiments, are determined by quantum chemistry theory.

Journal Article↗
PubMed2004

West Nile virus encephalitis in organ transplant recipients: another high-risk group for meningoencephalitis and death.

West Nile virus infection has been spreading westward across the continental United States since 1999. Although it often presents as a mild, self-limiting viral illness, it can result in a devastating meningoencephalitis in some patient populations, particularly the elderly. We report in this article on two immunosuppressed transplant patients who developed a severe meningoencephalitis caused by mosquito-borne West Nile virus infection. Suggestions for the prevention, diagnosis, and treatment of West Nile virus infection in this patient population are described.

Adult↗
PubMed2004

Real-time PCR-based genotyping assay for CXCR2 polymorphisms.

BACKGROUND: The human chemokine receptor CXCR2 (IL8RB) is a high affinity receptor for interleukin-8 as well as other CXC chemokines, and is involved in the chemotaxis of immune cells. Genetic variants of CXCR2 have potential relevance in various inflammatory human disorders. We developed a real-time polymerase chain reaction (PCR)-based allelic discrimination assay for the detection of the CXCR2 single nucleotide polymorphisms (SNPs) C785T, T1208C and G1440A. METHODS: Polymorphisms were delineated using PCR amplification of specific alleles (PASA). Allele-specific primers were developed for both wild-type and mutant alleles. An additional nucleotide mismatch at the third position from the 3' end of each primer was used to improve amplification specificity and to prevent generation of nonspecific products. Genotypes were assigned based on PCR growth curves and melt curve analysis performed on a SmartCycler using SYBR Green I chemistry. RESULTS: Genotyping assignments were successfully performed in a set of 20 human DNA samples, and were validated by comparison with results from direct DNA sequencing and agarose gel electrophoresis of PCR products. CONCLUSIONS: Due to its rapid and relatively inexpensive performance and accuracy, the presented allelic discrimination assay for CXCR2 polymorphisms has wide applicability, especially for high-throughput sample analysis in large population genotyping studies.

Black or African American↗
PubMed2004

Strongyloides hyperinfection syndrome after heart transplantation: case report and review of the literature.

Stronglyoides hyperinfection syndrome (SHS) is an augmentation of the infective life cycle of S stercoralis. Immunosuppressed patients, especially those taking corticosteroid therapy, are at risk. We present a case of fatal SHS with disseminated infection following orthotopic heart transplantation. The patient was treated with increased doses of immunosuppressive medications for graft rejection, including corticosteroids. A review of the literature describing the pathophysiology, host defenses and treatment of SHS is also presented. Diagnostic tests for S stercoralis are reviewed. SHS should be part of the differential diagnosis in immunosuppressed patients presenting with sepsis or gastrointestinal or pulmonary complaints. Pretransplant evaluation for parasitic infections, including strongyloidiasis, should occur in endemic areas or in patients at risk for occult infestation.

Bronchoalveolar Lavage Fluid↗
PubMed2004

An initial experience and evolution of laparoscopic hepatic resectional surgery.

BACKGROUND: The use of minimally invasive procedures has revolutionized modern surgery. Only recently has laparoscopy been introduced for use in hepatic surgery. METHODS: Patient demographics, tumor characteristics, and outcomes were evaluated for all initial cases of laparoscopic hepatic resection. RESULTS: Twenty-one resections were performed in 17 patients; 5 were performed for malignancy, of which 3 had underlying cirrhosis, and the remaining 12 for benign symptomatic disease. Mean patient age was 55.4 (range, 24-82 years). The mean number of lesions was 1.4 (range, 1-5), having an average size of 7.6 cm (range, 2-30 cm). Mean operative time was 2.8 hours (range, 2-5 hours) hours. Most resections involved 1 or more Couinaud segments. Mean blood loss was 288 cc (range, 50-150 cc). Complications included re-operation for hemorrhage (n=2), biliary leakage (n=1), and death from hepatic failure (n=1). Mean length of stay was 2.9 days (range, 1-14). When compared with our series of 100 patients who underwent open hepatic resection for benign tumors, significantly greater means ( P <.05) were noted for blood loss (485 cc), operative time (4.5 hours), and length of stay (6.5 days). CONCLUSIONS: Laparoscopic hepatic surgery, though complex, can be performed safely and efficaciously. Minimally invasive surgery appears to provide several distinct advantages over traditional open hepatic surgery. However, techniques for the laparoscopic control of bleeding and bile leak remain in their infancy.

Adult↗
PubMedDate not supplied

Onychomycosis: a 3-year clinicomycologic hospital-based study.

BACKGROUND: Despite onychomycosis being an established entity, only a few studies are available from the Indian subcontinent. The authors investigated the comprehensive pattern of the condition. AIM: To investigate the epidemiologic, clinical, and mycologic factors associated with onychomycosis in 50 patients using a prospective study design. METHODS: Fifty patients with potassium hydroxide-positive tests were evaluated according to a predetermined protocal recording details of epidemiologic, clinical, and mycologic characteristics. The collected data were analyzed to determine the correlation of various parameters. RESULTS: Distal and lateral subungual onychomycosis, total dystrophic onychomycosis, and superficial white onychomycosis variants of onychomycosis were identified, mostly in men 21-30 years of age (mean age, 34.5 years). Epidemiologic characteristics were instrumental to either initiate, perpetuate, or disseminate the disease process. Trichophyton rubrum and Trichophyton mentagrophytes were the main causative dermatophytes; yeasts and molds were less common. CONCLUSIONS: Recognition of onychomycosis is less difficult providing the clinician is aware of the entity. Should the etiologic diagnosis be made, its eradication is desirable to surmount its implication in the society at large.

Adolescent↗