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Biomedical subjects

S Jayakumar

Publications and source records attributed to S Jayakumar.

10 recordsLinked to original sources
PubMed2025

Multiplex PCR assay for the rapid detection of Klebsiella pneumoniae pathotypes.

Introduction. Klebsiella pneumoniae (Kp) is a major cause of nosocomial infections, with its evolving pathotypes including multidrug-resistant, hypervirulent (hvKp) and convergent strains posing significant diagnostic and treatment challenges due to combined antimicrobial resistance and virulence.Gap Statement. While there is a pressing requirement for thorough detection of Kp pathotypes, current assays in resource-limited environments are unable to effectively focus on essential carbapenemase and hypervirulence genes with the necessary reliability and precision.Aim. To develop and validate a multiplex PCR (m-PCR) assay capable of simultaneously detecting Kp isolates including those carrying partial or full virulence markers, alongside antimicrobial resistance.Methodology. In this study, an m-PCR assay was designed and optimized for the simultaneous detection of key biomarkers associated with hypervirulent (rmpA, rmpA2, iucA, peg344 and iroB), carbapenem-resistant (bla NDM, bla OXA-48-like and bla KPC) and convergent Kp pathotypes in clinical isolates. The assay was evaluated on clinical isolates and validated against whole-genome sequencing (WGS) data for accuracy, specificity and sensitivity.Results. The developed m-PCR assay exhibited 100% specificity when compared to WGS data, successfully detecting all target genes without cross-amplification in ATCC control strains. The assay demonstrated high sensitivity, efficiently amplifying bacterial genomes from minimal DNA input as low as 1 ng µl-1. Additionally, validation through sequencing confirmed the accuracy of detected amplicons.Conclusion. This m-PCR assay offers a rapid, sensitive and specific diagnostic tool for differentiating Kp pathotypes in clinical settings, aiding in timely intervention and improved infection control measures.

Klebsiella pneumoniae↗
PubMed1997

Circulating antioxidants in ulcerative colitis and their relationship to disease severity and activity.

Oxygen free radicals produced by neutrophils are important in the pathogenesis of mucosal damage in ulcerative colitis. Vitamin A, vitamin E and cysteine in the plasma can scavenge free radicals. In the present study, plasma levels of vitamin A, vitamin E, cysteine, cystine and protein-bound cysteine were measured in active ulcerative colitis before and immediately after treatment of the active disease, and correlated with disease severity, extent and activity. Plasma vitamin A and cysteine were significantly reduced in active ulcerative colitis compared with controls. Levels of vitamin E, cystine and protein-bound cysteine were not significantly altered in active ulcerative colitis. Vitamin A and cysteine concentrations returned to normal levels (P < 0.05) within 2 weeks of treating active colitis. There were significant negative correlations between clinical severity and the plasma concentrations of vitamin A and cysteine. Plasma cysteine levels also correlated inversely to disease extent. Depletion of the circulating antioxidants, vitamin A and cysteine, in active ulcerative colitis is likely to be important in the pathophysiology of the disease.

Adolescent↗
PubMed1983

T and B lymphocyte subsets in fenoprofen nephropathy.

Renal failure due to combined acute interstitial nephritis and minimal-change glomerulopathy is reported in two patients after fenoprofen therapy. In the interstitial infiltrates, T lymphocytes predominated over B lymphocytes in a ratio of four to one. The majority of B lymphocytes present were IgE-bearing cells. Among the T cells, the ratio of cytotoxic/suppressor cells to helper-inducer cells was three to one. Repeated renal biopsy in one patient after steroid-induced clinical remission demonstrated resolution of the inflammatory infiltrate and restoration of normal glomerular foot processes. The theoretic and practical implications of these findings are discussed.

Acute Kidney Injury↗
PubMed1983

Talwin addict nephropathy.

Three patients with a 2-3 year history of parenteral abuse of pentazocine hydrochloride (Talwin) developed membranoproliferative glomerulonephritis type I. Clinical presentation included nephrotic syndrome, microscopic hematuria, and hypertension. Tissue studies disclosed 1+ to 4+ mesangial and subendothelial deposits of immunoglobulins (predominantly IgM) and complement components C1Q, C3 and C4 with focal reduplications of glomerular basement membranes. Glomerular C3 receptor studies performed on one patient demonstrated diffuse loss of receptor activity correlating with localization of immune deposits. Serum studies showed decreased levels of C3, elevated levels of IgM (greater than 2 SD) (three patients) and circulating immune complexes (two patients). Repeated blood and urine cultures were negative. Immune mechanisms may be involved in the pathogenesis of Talwin addict nephropathy.

Adult↗
PubMed1980

The use of plastic jackets in the non-operative treatment of idiopathic scoliosis. Preliminary report.

One method of treatment for scoliosis consists of using a custom-made plastic underarm jacket made of Orthoplast. The results of treatment in the first forty-eight patients with idopathic scoliosis to complete the treatment program showed arrest of the progression of the curve in forty-two. Comparisons were made with the Milwaukee brace. The key prognostic factors for success appeared to be the severity and flexibility of the curve at the start of treatment.

Adolescent↗
PubMed1980

Slipped capital femoral epiphysis with hypothyroidism treated by nonoperative method.

Patients receiving growth hormone or thyroid hormone are likely to develop a slipped capital femoral epiphysis during the period of spurt in growth. While pin fixation of these hips has been the popular method of treatment, it is possible to treat Grade I slips successfully by nonoperative methods provided that protection from weight-bearing is maintained until fusion of the epiphysis is complete.

Adolescent↗
PubMed1977

Study of the sites and mechanisms of action of bumetanide in man.

Acute clearance studies were performed in normal subjects to establish the site(s) and mechanism of action of the new diuretic agent, bumetanide (3-n-butylamino-4-phenoxy-5-sulfamylbenzoic acid), in the human kidney. When the drug was administered during water diuresis, solute-free water formation was unchanged associated with a peak increment in fractional sodium excretion of approximately 15% of filtered load. However, studies performed in hydropenic subjects demonstrated a virtual abolition of free water reabsorption. The diuretic caused a mild phosphaturia which did not appear to be related to alterations in parathyroid hormone. Furthermore, whereas net hydrogen ion excretion and urinary pH were unchanged, the excretion of ammonium ion, titratable acidity and bicarbonate all increased mildly. Taken together, the data suggest that the primary site of action of bumetanide is the medullary portion of the ascending limb of the loop of Henle, but that in addition, bumetanide inhibits the transport of sodium in the proximal nephron. Despite the fact that the drug is a sulfonamide derivative, its proximal activity seems unrelated to a carbonic anhydrase inhibitory effect. More likely the agent interferes with proximal reabsorption by impairing sodium-phosphate linked transport.

Administration, Oral↗
PubMedDate not supplied

Rigid flatfoot.

The proper management of the rigid flat-foot requires an accurate diagnosis since the condition is treated on causal or rational basis. Calcaneonavicular coalition best seen on an oblique view of the foot may be treated by resection of the coalition with extensor digitorum brevis interposition. If the diagnosis is made sufficiently early, the resection can lead to an essentially normal foot. Coalition between the talus and the calcaneus may occur in the posterior, middle or anterior facet. The most common coalitions are seen in the middle facet area followed by those in the anterior facet with the posterior facet coalition rarely being seen. Coalitions in the area of the middle facet are usually managed nonoperatively; triple arthrodesis is used only if symptoms are not relieved by nonoperative measures. Resection of a talocalcaneal coalition in the middle facet is rarely indicated but occasionally will give relief when the coalition either presses on the medial plantar nerve or causes a mechanical disturbance of the ankle. Anterior facet coalitions should receive a trial of cast immobilization but frequently require triple arthrodesis. Other conditions such as rheumatoid and post-traumatic arthritis will frequently respond to a period of immobilization in a plaster cast. Triple arthrodesis has not been required in rheumatoid arthritis in the author's series but occasionally is necessary in the post-traumatic rigid flatfoot. Other rare causes of the rigid flatfoot should be kept in mind for a complete diagnostic evaluation since even a neoplasm (fibrosarcoma) has been reported to cause this symptom complex.

Arthrodesis↗