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Biomedical subjects

P Gupta

Publications and source records attributed to P Gupta.

At least 91 records · Page 5Linked to original sources
PubMed2000

Longitudinal quantitative measures of the natural course of low back pain recovery.

STUDY DESIGN: A prospective study was developed to quantify acute low back pain recovery. OBJECTIVE: To compare traditional self-report measures of low back pain recovery with a quantitative measure of recovery. SUMMARY OF BACKGROUND DATA: The magnitude of low back disorders in society continues to be a problem. To prevent secondary injuries, an understanding of recovery must be gained by comparing the natural course of recovery using several outcome measures. METHODS: For this study, 16 occupational and 16 nonoccupational patients with low back pain were recruited. Recovery was monitored prospectively every 2 weeks for 3 to 6 months, using subjective work status, pain symptoms, activities of daily living, and objective functional performance probability (trunk kinematics). RESULTS: Return to work underestimated the percentage of subjects impaired, as compared with all other outcome measures. Symptoms, activities of daily living, and functional performance probability all showed similar patterns of recovery for 0 to 12 weeks. At 14 weeks, there was a lag in functional performance recovery. Both symptoms and activities of daily living indicated that 80% of the population was recovered, whereas functional performance indicated the figure to be 68%. CONCLUSION: This prospective study demonstrates the natural course of recovery using several outcome measures. The objective kinematic functional performance measure of recovery quantifies a different aspect of impairment not evaluated by traditional subjective measures. Use of several outcome measures may lead to a better understanding of low back pain recovery or residual impairment, which may minimize the risk of recurrent injury.

Activities of Daily Living↗
PubMed2000

Human immunodeficiency virus type 1 shedding pattern in semen correlates with the compartmentalization of viral Quasi species between blood and semen.

High levels of human immunodeficiency virus (HIV) type 1 have been detected in semen at all stages of disease. However, it is not clear whether HIV-1 is shed in semen continuously or intermittently. In a prospective longitudinal study, viral RNA was measured weekly for 10 weeks in semen and blood of HIV-seropositive subjects. Results showed three different patterns of HIV-1 shedding in semen: none (28%), continuous (28%), and intermittent (44%). In contrast, there was no change in blood plasma virus load during the study period. Phylogenetic analysis of the envelope sequences of HIV-1 RNA in semen and blood revealed distinct virus populations in semen and blood of intermittent shedders but similar virus populations in the semen and blood of continuous shedder. These results indicate for the first time that HIV-1 is shed primarily in an intermittent manner and that shedding patterns of HIV-1 in semen are related to compartmentalization of HIV-1 between semen and blood.

Cell Compartmentation↗
PubMed2000

The in vivo pharmacological profile of eletriptan (UK-116,044): a potent and novel 5-HT(1B/1D) receptor agonist.

The anti-migraine drug, eletriptan [(R)-3-(1-methyl-2-pyrrolidinylmethyl)-5-[2-(phenylsulphonyl )ethyl]-1 H-indole; UK-116,044], is a novel 5-HT(1B/1D) receptor agonist. In this paper, the regional vasoconstrictor profile of eletriptan, in comparison with sumatriptan, was examined in the anaesthetised dog. The inhibitory actions of eletriptan on neurogenic inflammation in rat dura mater were also assessed. In the anaesthetised dog, eletriptan (1-1000 microg kg(-1) i.v.) produced a dose-dependent reduction of carotid arterial blood flow with a similar potency and maximum effect to sumatriptan (ED(50) values: eletriptan and sumatriptan, 12 and 9 microg kg(-1), i.v., respectively). However, eletriptan exhibited a significantly lower potency than sumatriptan in reducing coronary artery diameter (ED(50) values: 63 and 19 microg kg(-1), i.v., respectively, P<0.05). In the femoral circulation, sumatriptan caused a significant reduction in arterial blood flow (ED(50) 35 microg kg(-1) i.v.) whereas eletriptan (1-1000 microg kg(-1) i.v.) had no significant effect upon femoral arterial blood flow when compared to vehicle-treated animals. In rats, eletriptan (30-300 microg kg(-1) i.v.) administered prior to electrical stimulation of the trigeminal ganglion produced a dose-related and complete inhibition of plasma protein extravasation in the dura mater (mean extravasation ratio: control 1.9; eletriptan 1.0, minimum effective dose 100 microg kg(-1), P<0.05). The potency and maximum effect of eletriptan was identical to that of sumatriptan in this model. When administered during a period of continual stimulation of the trigeminal nerve, eletriptan (100 microg kg(-1) i.v.) produced a complete inhibition of plasma protein extravasation. The ability to reduce canine carotid arterial blood flow and inhibit neurogenic inflammation in rat dura mater suggests that vascular and neurogenic mechanisms may contribute to eletriptan's clinical efficacy in migraine patients. In addition, eletriptan exhibits some selectivity for reducing carotid arterial blood flow when compared with femoral arterial blood flow and coronary artery diameter, in the anaesthetised dog.

Anesthesia↗
PubMed2000

Dependence of CD8+ T-cell-mediated suppression of HIV type 1 on viral phenotypes and mediation of phenotype-dependent suppression by viral envelope gene and not by beta-chemokines.

CD8+ T-cell-mediated HIV-1 suppressive activity has been shown against a number of strains of HIV-1 and HIV-2. In this study using a semiquantitative assay, we showed that CD8+ T cells from seropositive subjects and herpes virus saimiri transformed CD8+ T-cell clones from HIV-1-infected subjects exhibited 5 to 100-fold higher suppressive activity against slow replicating nonsyncytia-inducing strains (Slow/NSI) as compared to fast replicating syncytia-inducing strains (Fast/SI) of HIV-1. Such differential suppressive activity was not due to beta-chemokines as evidenced by the lack of blocking activity of antibodies to RANTES, MIP-1beta, and MIP-1alpha on the antiviral activities of CD8+ T cells. Moreover, there was no correlation between the level of CD8+ T-cell suppression and the level of these beta-chemokines in culture supernatant. Results from the CD8+ T-cell-mediated suppressive activity against two molecular cloned virus ME1 (Slow/NSI), ME46 (Fast/SI), and their interstrain recombinants indicate that the envelope gene carries a major genetic determinant responsible for this phenotypic-dependent differential suppressive activity.

CD4-Positive T-Lymphocytes↗
PubMed2000

Human LTC-IC can be maintained for at least 5 weeks in vitro when interleukin-3 and a single chemokine are combined with O-sulfated heparan sulfates: requirement for optimal binding interactions of heparan sulfate with early-acting cytokines and matrix proteins.

We have shown that stromal O-sulfated heparan sulfate glycosaminoglycans (O-S-GAGs) regulate primitive human hematopoietic progenitor cell (HPC) growth and differentiation by colocalizing heparin-binding cytokines and matrix proteins with HPC in stem cell "niches" in the marrow microenvironment. We now show that long-term culture-initiating cells (LTC-IC) are maintained for 5 weeks in the absence of stroma when O-S-GAGs are added to IL-3 and either MIP-1alpha or PF4 (LTC-IC maintenance without GAGs, 32 +/- 2%; with GAGs, 95 +/- 7%; P <.001). When cultured with 5 additional cytokines, O-S-GAGs, IL-3, and MIP-1alpha, LTC-IC expanded 2- to 4-fold at 2 weeks, and 92 +/- 8% LTC-IC were maintained at 5 weeks. Similar results were seen when PF4 replaced MIP-1alpha. Although O-S-GAG omission did not affect 2-week expansion, only 20% LTC-IC were maintained for 5 weeks. When O-S-heparin was replaced by completely desulfated-, N-sulfated (O-desulfated), or unmodified heparins, LTC-IC maintenance at week 5 was not better than with cytokines alone. Unmodified- and O-S-heparin, but not desulfated- or N-sulfated heparin, bound to MIP-1alpha, IL-3, PF4, VEGF, thrombospondin, and fibronectin. However, the affinity of heparin for thrombospondin and PF4, and the association and dissociation rates of heparin for PF4, were higher than those of O-S-heparin. We conclude that (i) although cytokines may suffice to induce early expansion, adult human LTC-IC maintenance for longer than 1 month requires O-S-GAGs, and (ii) HPC support may depend not only on the ability of GAGs to bind proteins, but also on optimal affinity and kinetics of interactions that affect presentation of proteins in a biologically active manner to progenitors. (Blood. 2000;95:147-155)

Adult↗
PubMed2000

Potential pitfalls in nuclear medicine: a paediatric teaching case.

An infant with complex cardiac defects and isomerism had a persistent pyrexia of undetermined aetiology following cardiac surgery. Radionuclide leucocyte scan showed a focus of increased uptake in the right upper quadrant (RUQ) felt to be compatible with an abscess. However, correlation with clinical data and multimodality imaging allowed the correct diagnosis of ectopic splenic tissue in the RUQ to be made. This report emphasises the need for an integrated approach to imaging. Patients with abnormalities of viscero-atrial situs require careful assessment of their splenic status. Visceral heterotaxy may result in confusing imaging appearances unless the anatomy has been accurately documented.

Abdomen↗
PubMed2000

Genes involved in senescence and immortalization.

Senescence is now understood to be the final phenotypic state adopted by a cell in response to several distinct cell physiological processes, including proliferation, oncogene activation and oxygen free radical toxicity. The role of telomere maintenance in immortalization and the roles of p16(INK4A), p19(ARF), p53 and other genes in senescence are being further elucidated. Significant progress continues to be made in our understanding of cellular senescence and immortalization.

Animals↗
PubMed2000

Modern immunosuppression.

The current treatment of posttransplant lymphoproliferative disease (PTLD) includes prophylaxis at the time of transplant, decreasing or stopping immunosuppresion and initiation of antiviral therapy in patients with polymerase chain reaction or clinical evidence of PTLD, and judicial reintroduction of immunosuppression in patients who have cleared their PTLD and have begun to have rejection. The pharmacology, pharmacokinetics, notable side effects, and toxicities of the immunosuppressive agents are described in this article. At the conclusion of each section the author's current practice with these agents and treatment strategies are described.

Antibodies↗
PubMed2000

Combinatorial synthesis of unsymmetrical secondary amines. Application to arylethanolamines, arylpropanolamines and aryloxypropanolamines.

Combinatorial libraries of unsymmetrical secondary amines: arylethanolamine, arylpropanolamines and aryloxypropanolamines [1], in particular have been synthesized by four different routes using styrenes, aldehydes, hydroxyaromatic acids and bromoaliphatic acids. The structurally diverse libraries were generated in parallel format using solid phase methodology. The compounds corresponding to prototype I-IV were obtained in high yields and purities.

Amines↗
PubMed2000

Diagnostic value of lymph node fine needle aspiration cytology: an institutional experience of 387 cases observed over a 5-year period.

Lymph node fine needle aspiration (LNFNA) cytology is valuable in solving the diagnostic problems of clinical adenopathy. The usefulness of the procedure in the staging and diagnosis of various malignant and lymphoproliferative tumours, as well as its role in distinguishing reactive hyperplastic lymph nodes from lymphoma, has been documented in the literature generally on an individual basis. We report our cumulative 5 year experience of LNFNA representing 387 cases. Approximately half (n = 182) were diagnosed as either metastatic carcinoma or melanoma; in 54 cases (30%) excisional biopsy or tissue study was performed to confirm the diagnosis; there was only one false-positive diagnosis of a metastatic squamous carcinoma rendered on a submandibular lymph node. Sixty-one lymphoma cases were successfully diagnosed via LNFNA with no false positives; concurrent flow cytometry was utilized in 51% (n = 31) of the 61 cases and supported the cytologic diagnosis of lymphoma in 27 of the 31 cases (87%). A benign or reactive lymph node process was also diagnosed via LNFNA alone or in combination with flow cytometry in 48 cases with only five false negatives, which included four cases of mantle cell lymphoma and one case of melanoma. Unsatisfactory cases accounted for 12%, and represented specimens obtained by 'Wang needle' or other emerging techniques. Our study demonstrates that LNFNA can be an accurate, economical and rapid diagnostic procedure.

Adult↗
PubMed2000

Prospective functional evaluation of the surgical treatment of neurogenic claudication in patients with lumbar spinal stenosis.

A prospective evaluation of patients with lumbar spinal stenosis undergoing operative treatment was performed using treadmill-bicycle functional testing as well as Oswestry and Visual Analog Pain scales for self-assessment. Thirty-two patients undergoing spinal stenosis decompression with and without a concomitant spinal fusion were prospectively evaluated, preoperatively and a minimum of 2 years postoperatively. Surgical treatment was demonstrated to produce significant improvement in walking ability, and to a lesser degree, in the ability to bicycle 2 years postoperatively. Improvement in patient function demonstrated on the Oswestry questionnaire correlated with decreased pain observed on the Visual Analog Pain scale. The treadmill-bicycle test appears to be a useful tool for the differential diagnosis of neurogenic claudication and may be used as an objective test of postoperative outcome.

Adult↗
PubMed2000

Is lactobacillus GG helpful in children with Crohn's disease? Results of a preliminary, open-label study.

BACKGROUND: Lactobacillus GG is a safe probiotic bacterium known to transiently colonize the human intestine. It has been found to be useful in treatment of several gastrointestinal conditions characterized by increased gut permeability. In the current study, the efficacy of Lactobacillus GG was investigated in children with Crohn's disease. METHODS: In this open-label pilot evaluation viewed as a necessary preliminary step for a possible subsequent randomized placebo-controlled trial, four children with mildly to moderately active Crohn's disease were given Lactobacillus GG (10(10) colony-forming units [CFU]) in enterocoated tablets twice a day for 6 months. Changes in intestinal permeability were measured by a double sugar permeability test. Clinical activity was determined by measuring the pediatric Crohn's disease activity index. RESULTS: There was a significant improvement in clinical activity 1 week after starting Lactobacillus GG, which was sustained throughout the study period. Median pediatric Crohn's disease activity index scores at 4 weeks were 73% lower than baseline. Intestinal permeability improved in an almost parallel fashion. CONCLUSIONS: Findings in this pilot study show that Lactobacillus GG may improve gut barrier function and clinical status in children with mildly to moderately active, stable Crohn's disease. Randomized, double-blind, placebo-controlled trials are warranted for a final assessment of the efficacy of Lactobacillus GG in Crohn's disease.

Adolescent↗
PubMed2000

Bioadhesives for intraocular use.

BACKGROUND/PURPOSE: A safe, effective adhesive could be useful in the management of retinal holes or tears and selected complicated retinal detachments, as well as for attaching a small electronic device (retinal prosthesis) to the retina. In this study, we examined nine commercially available compounds for their suitability as intraocular adhesives. METHODS: The following materials were studied: commercial fibrin sealant, autologous fibrin, Cell-Tak, three photocurable glues, and three different polyethylene glycol hydrogels. An electronic strain gauge measured the adherence forces between different glues and the retina. The stability of hydrogels at body temperature and the impermeability of the hydrogel adhesive to dextran blue were examined. Long-term biocompatibility testing of the most promising glues in terms of adhesive force, consistency, and short-term safety (hydrogels) were done in rabbits. Funduscopy, electroretinogram, and histology of the retina were performed. RESULTS: Hydrogels had 2 to 39 times more adhesive force (measured in mN) than the other glues tested. They liquefied at body temperature after 3 days to a few months. Hydrogels were impermeable to dextran blue. One type of hydrogel proved to be nontoxic to the retina. CONCLUSIONS: Hydrogels proved to be superior for intraocular use in terms of consistency, adhesiveness, stability, impermeability, and safety.

Adhesiveness↗