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Biomedical subjects

K Singh

Publications and source records attributed to K Singh.

At least 19 recordsLinked to original sources

Effects of epidural ketamine-xylazine combination on the clinicophysiological and haematobiochemical parameters of uraemic and healthy goats.

Xylazine-ketamine combination was evaluated for its efficacy and safety after epidural administration in uraemic and healthy goats. The combination (xylazine 0.025 mg/kg and ketamine 2.5 mg/kg) was administered to uraemic (n = 6) and healthy (n = 6) animals in the lumbosacral epidural space. The combination was evaluated in terms of clinical, physiological, haematological and biochemical parameters. The onset of analgesia was faster in healthy animals than in uraemic animals. Xylazine and ketamine produced complete analgesia of tail, perineum, inguinal and thigh regions in all animals of both groups. However, healthy animals showed longer duration of complete analgesia than did uraemic animals. Greater ataxia was recorded in healthy animals than in uraemic animals. The heart rate showed a significant decrease in both groups; however, respiratory rate and rectal temperature did not show any significant changes. Haemoglobin, packed cell volume and total leukocyte count decreased non-significantly in both groups. Total leukocyte count was significantly higher in uraemic animals. A significantly higher value of urea nitrogen and creatinine was recorded in uraemic animals. The blood electrolytes (Na+, K+ and Cl-) and blood gases (PO2 and PCO2) did not show any significant changes in both groups; however, base excess was significantly higher in uraemic animals. The effects produced by the combination on different systems were transient and values normal as the effect of the drugs wore off. The results suggest that the combination when used epidurally in uraemic goats produced effective and safe surgical analgesia.

Analgesia, Epidural↗

The effect of levonorgestrel-releasing intrauterine system use on menstrual blood loss and the hemostatic, fibrinolytic/inhibitor systems in women with menorrhagia.

BACKGROUND: Menorrhagia is known to be associated with uterine fibroids, adenomyosis, pelvic infections, endometrial polyps and clotting defects. A viable alternative therapy to hysterectomy should alleviate heavy menstrual blood flow and consequently improve the quality-of-life measures in women presenting with menorrhagia. The levonorgestrel-releasing intrauterine system (LNG-IUS) ranks higher than medical treatments in terms of efficacy, comparable improvements in quality of life and psychological well-being. OBJECTIVE: The purpose of the study was to determine the effects of 6 months of LNG-IUS use on menstrual blood loss and the hemostatic, fibrinolytic/inhibitor systems in blood and the endometrium in women with menorrhagia with known pathologic causes. PATIENTS AND METHODS: Samples from 41 women were analyzed. Hemoglobin, hematocrit, thrombelastography, tissue-type plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), u-PA receptor (u-PAR), plasminogen activator inhibitor-1/2 (PAI-1/2), D-dimer and von Willebrand factor (VWF) were determined, and t-PA, u-PA and PAI-1/2 were also determined in endometrial tissue extracts. RESULTS: Menorrhagia was reduced in 89% of women by 3 months; by 6 months all women had no menorrhagia, and 39% of women had become amenorrhoeic. Hemoglobin and hematocrit levels showed improvement, and reached normal reference levels by 6 months. There were no systemic changes in the fibrinolytic/inhibitor systems and VWF, except for a decreased u-PAR level. However, in the endometrium, significant elevations in PAI-1/2 together with u-PAR levels were seen at 6 months. CONCLUSIONS: The slow levonorgestrel-release intrauterine device use results in high expression of fibrinolytic inhibitors (PAI-1/2) and upregulated u-PAR expression in the endometrium. Systemic hemostasis was not significantly altered. The study demonstrated that LNG-IUS is highly effective in the treatment of menorrhagia with known pathologic causes.

Adult↗

Anatomic landmarks: their usefulness in safe laparoscopic cholecystectomy.

The incidence of bile duct injury in laparoscopic cholecystectomy is 0.3% to 1.0%. This is higher than the incidence reported for open cholecystectomy (i.e., 0.1-0.2%), and the surgeons all over the world are relentlessly trying to find the ways and means to lower this incidence. Various operating strategies, techniques, and instrumentations such as the 0 degrees telescope, intraoperative cholangiogram, hydrodissection, and peanut gauze dissection have been claimed by various authors to minimize the risk of bile duct injury during cholecystectomy. However, the surgical fraternity agrees that there has been no substitute for meticulous dissection and display of various vital structures near the common bile duct. The authors describe seven anatomic landmarks encountered during laparoscopic cholecystectomy that assist in safe dissection to prevent bile duct and vascular injury. On the basis of their experience, they believe that if surgeons adhere to these landmarks, excellent results can be achieved.

Adult↗

Preemptive, but not reactive, spinal cord stimulation mitigates transient ischemia-induced myocardial infarction via cardiac adrenergic neurons.

Our objective was to determine whether electrical neuromodulation using spinal cord stimulation (SCS) mitigates transient ischemia-induced ventricular infarction and, if so, whether adrenergic neurons are involved in such cardioprotection. The hearts of anesthetized rabbits, subjected to 30 min of left anterior descending coronary arterial occlusion (CAO) followed by 3 h of reperfusion (control), were compared with those with preemptive SCS (starting 15 min before and continuing throughout the 30-min CAO) or reactive SCS (started at 1 or 28 min of CAO). For SCS, the dorsal C8-T2 segments of the spinal cord were stimulated electrically (50 Hz, 0.2 ms, 90% of motor threshold). For preemptive SCS, separate groups of animals were pretreated 15 min before SCS onset with 1) vehicle, 2) prazosin (alpha(1)-adrenoceptor blockade), or 3) timolol (beta-adrenoceptor blockade). Infarct size (IS), measured with tetrazolium, was expressed as a percentage of risk zone. In controls exposed to 30 min of CAO, IS was 36.4 +/- 9.5% (SD). Preemptive SCS reduced IS to 21.8 +/- 6.8% (P < 0.001). Preemptive SCS-mediated infarct reduction was eliminated by prazosin (36.6 +/- 8.8%) and blunted by timolol (29.4 +/- 7.5%). Reactive SCS did not reduce IS. SCS increased phosphorylation of cardiac PKC. SCS did not alter blood pressure or heart rate. We conclude that preemptive SCS reduces the size of infarcts induced by transient CAO; such cardioprotection involves cardiac adrenergic neurons.

Animals↗

Deficiency of beta1 integrins results in increased myocardial dysfunction after myocardial infarction.

OBJECTIVE: To study the role of beta1 integrins in left ventricular (LV) remodelling after myocardial infarction (MI). METHODS AND RESULTS: LV structural and functional alterations were determined in wild-type (WT) and beta1 integrin heterozygous knockout (hKO) mice one month after MI. MI increased beta1 integrin expression in both groups; however, the increase was lower in hKO. Infarct size was similar in WT and hKO mice, whereas lung wet weight to dry weight ratio was increased in the hKO-MI mice (5.17 (SE 0.13) v 4.60 (0.15) in WT-MI, p < 0.01). LV end systolic and end diastolic diameters were significantly higher and percentage fractional shortening was significantly lower in hKO-MI. The ratio of peak velocity of early LV filling (E wave) to that of the late LV filling (A wave) and the isovolumic relaxation time (IVRT) were increased in both MI groups but the increase in IVRT was significantly higher in hKO-MI group than in WT-MI mice. Langendorff perfusion analysis indicated reduced peak LV developed pressure and increased LV end diastolic pressure in both MI groups. The reduction in peak LV developed pressure (36.7 (2.2) v 53.4 (1.9) mm Hg, p < 0.05) and increase in LV end diastolic pressure was higher in hKO-MI than in WT-MI. Increase in fibrosis was not different between the two MI groups. The increase in myocyte circumference was higher in the hKO-MI group (p < 0.001 v WT-MI). The number of apoptotic myocytes was significantly higher in hKO-MI than in WT-MI mice (p < 0.005) three days after MI. The number of necrotic myocytes was not different between the two MI groups. CONCLUSION: beta1 integrins are crucial in post-MI remodelling with effects on LV function, hypertrophy and apoptosis.

Animals↗

Comparison of some trace elements concentration in blood, tumor free breast and tumor tissues of women with benign and malignant breast lesions: an Indian study.

Fifty women residing in and around New Delhi, India and identified to have benign (25 nos.) and malignant (25 nos.) breast lesions were studied for the first time to access the association between environmental exposure to lead and risk of breast cancer and to determine the potential of changes in trace elements concentration as a diagnostic marker and/or its etiological involvement in the disease. Blood, tumor tissue and breast adipose tissue from tumor free area from each patient of the two groups, collected at the time of lumpectomy or mastectomy (only blood sample was collected from disease free control group), were analyzed to determine the concentration of Pb, Zn, Cu, Fe and Ca using Atomic Absorption Spectrometry. Blood lead was significantly higher in malignant cases than in those of benign and control (p<0.05 each). Lead level was also higher in tumor tissue when compared with their respective normal tumor free breast tissue, though non-significant, in both benign and malignant cases. Interestingly, Zn, Fe, and Ca levels were higher in blood of malignant cases than in those of their benign counterparts. Furthermore, these metals were also higher in tumor of malignant and benign cases as compared to normal tumor free breast tissue, many of them statistically significant (p<0.05/0.01/0.001). However, Cu level was insignificantly lower in the blood and tumor tissue of malignant cases when compared with their benign counterparts while it was significantly higher (p<0.05) in tumor of benign cases when compared with those of their respective normal tumor free breast tissue. There were statistically significant correlations between lead and trace element levels only in normal tumor free breast tissue of benign and malignant cases (r=0.41-0.73; p<0.05-0.001) but neither in blood nor tumor tissue of the two groups. These results suggest that in the backdrop of existing experimental and epidemiological evidences exposure to lead may be one of the risk factors for breast lesions; though it warrants further investigation. Further, modulation of trace elements level in both benign and malignant breast diseases patients may be of potential to be used as diagnostic marker of the disease process and its possible relationship etiologically.

Adult↗

Role of N-acetylcysteine in rifampicin-induced hepatic injury of young rats.

AIM: To study the role of N-acetylcysteine (NAC) as a protective agent in rifampicin (RMP)-induced oxidative hepatic injury of young rats. METHODS: Hepatic injury was produced by giving 50 mg/kg body weight/day of RMP for 3 wk. A dose of NAC (100 mg/kg body weight/day) was given in combination with RMP intraperitoneally. Analysis of lipid peroxidation, thiol levels, cytochrome P450, superoxide dismutase (SOD), catalase, glutathione peroxidase, reductase and transferase were estimated in liver along with the body weight, liver weight and histological observations. RESULTS: RMP exposure resulted in no change in body and liver weight while antioxidative enzymes were altered but the non protein thiol (GSH) status was well preserved. Cytochrome P450 system and peroxidation of lipids were induced by RMP exposure. Partial protection was observed with NAC against RMP-induced changes in liver, which was evidenced from the prevention of increase in lipid peroxidation and the reduction in SOD and catalase enzyme levels. CONCLUSION: NAC protects young rats against RMP-induced oxidative hepatic injury.

Acetylcysteine↗

HIDA scan ejection fraction does not predict sphincter of Oddi hypertension or clinical outcome in patients with suspected chronic acalculous cholecystitis.

BACKGROUND: Hepatobiliary iminodiacetic scan with ejection fraction (HIDA EF) is used to evaluate chronic acalculous cholecystitis (CAC). A presumed etiology of CAC is sphincter of Oddi hypertension (SOH). In this study, we evaluated the value of HIDA EF to predict patient response to laparoscopic cholecystectomy and to identify SOH. METHODS: A prospective study of 93 patients with biliary pain but without gallstones (CAC) who underwent preoperative HIDA EF was conducted. At laparoscopic cholecystectomy, transcystic antegrade biliary manometry was performed to determine the SO pressure. Patients were evaluated postoperatively for response to cholecystectomy. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. The outcomes were compared with the clinical impression. RESULTS: Of the 93 patients with both HIDA EF and SOP measurements, 50 had abnormal EF (< 35%); of these, 29 had SOH (SO pressure > or = 40 mmHg). Of the 43 patients with normal HIDA EF, 30 had SOH. The sensitivity was 49%, specificity 38%, PPV 58%, and NPV 30%. Eighty-six of the 93 patients returned for follow-up evaluation. Follow-up ranged from 0 to 99 months, with a mean of 26.4 months. Overall, 73 patients (85%) improved. Of the 46 with abnormal HIDA EF, 42 (91%) improved. Of the 40 patients with normal HIDA EF, 31 (77.5%) improved. The sensitivity was 57.7%, specificity 69.2%, PPV 91.3%, and NPV 22.5%. CONCLUSION: Although the PPV of abnormal HIDA EF is high, it is not much better than the clinical impression. The sensitivity and specificity are marginal. The NPV is poor. Based on the review of these 93 patients, HIDA EF is not reliable for identifying CAC. We recommend that patients with normal HIDA EF have additional testing or consultation before ruling out CAC. HIDA EF does not predict SOH.

Acalculous Cholecystitis↗

Daptomycin for the treatment of vancomycin resistant Enterococcus faecium bacteremia.

The best therapeutic options for serious infections due to vancomyci resistant Enterococcus (VRE) remain unclear. We describe the successful treatment of vancomycin resistant Enterococcus faecium bacteremia in 2 patients using daptomycin. We also briefly review the literature on antibiotic options for VRE infection including the use of daptomycin.

Aged↗

Chordoma: 6 years' experience at a tertiary centre.

Nine patients with a histologically proven diagnosis of chordoma seen at the Department of Radiation Oncology, Maulana Azad Medical College and Lok Nayak Hospital between January 1999 and December 2004 were retrospectively reviewed with respect to age, sex, presentation, location of tumour, treatment, response, recurrence, metastasis and follow up. Chordoma constituted 0.07% of total cancer cases registered over 6 years. Out of nine patients, eight were males and one was female with median age at time of diagnosis 52 years (range 34-68 years). All had sacrococcygeal lesions except one who had a spheno-occipital lesion. Seven patients had undergone either subtotal or gross total resection whereas only biopsy had been carried out in two of them. All patients received radiation therapy, seven in a postoperative setting and two for palliation. Follow-up period ranged from 2 to 50 months. Four patients died--the first after fourth fraction of radiation, second after 10 days of treatment, third of progressive lesion in sphenoidal region despite resection and radiation and fourth of local recurrence in the sacrococcyx. One patient developed distant metastases in the lungs and subcutaneous tissue over the scalp along with local recurrence; he is still alive. Two patients are locally free of disease whereas the other two were lost to follow up. The present analysis was undertaken to review our institutional experience with an aim to provide a practical approach to these tumours. In this report, these cases are discussed and the published works have been reviewed for the optimal management of patients with chordoma.

Adult↗

Terminalia chebula (fruit) prevents liver toxicity caused by sub-chronic administration of rifampicin, isoniazid and pyrazinamide in combination.

Terminalia chebula Gertn. (Combetraceae) is an important herbal drug in Ayurvedic pharmacopea. In the present study, a 95% ethanolic extract of T. chebula (fruit) (TC extract), which was chemically characterized on the basis of chebuloside II as a marker, was investigated for hepatoprotective activity against anti-tuberculosis (anti-TB) drug-induced toxicity. TC extract was found to prevent the hepatotoxicity caused by the administration of rifampicin (RIF), isoniazid (INH) and pyrazinamide (PZA) (in combination) in a sub-chronic mode (12 weeks). The hepatoprotective effect of TC extract could be attributed to its prominent anti-oxidative and membrane stabilizing activities. The changes in biochemical observations were supported by histological profile.

Animals↗

Severe pulmonary disease due to multisystemic eosinophilic epitheliotropic disease in a horse.

Multisystemic eosinophilic epitheliotropic disease was diagnosed histologically in a 17-year-old Quarter Horse intact mare that was presented with a chronic history of respiratory distress. At necropsy, the lungs were poorly collapsed and the pulmonary parenchyma contained innumerable, discrete, spherical nodules in a miliary pattern. A few similar nodules were scattered in the liver and the renal lymph nodes. Histologically, these nodules consisted of fibrosing eosinophilic granulomas. Based on histologic findings and the absence of an etiologic agent, a diagnosis of multisystemic eosinophilic epitheliotropic disease was made.

Animals↗

Fatal systemic phaeohyphomycosis caused by Ochroconis gallopavum in a dog (Canis familaris).

A 5-year-old Shetland Sheepdog was presented with a history of weakness, ataxia, anemia, thrombocytopenia, and occasional seizures. The dog had been treated for 6 months with prednisone for inflammatory bowel disease. A positive titer for Ehrlichia canis was detected 6 months before referral. The initial physical examination revealed a weak, laterally recumbent dog with pale mucous membranes. Neurologic examination revealed multiple neurologic deficits. A complete blood cell count (CBC) revealed normochromic, normocytic, nonregenerative anemia; lymphopenia; thrombocytopenia; and neutrophilic and monocytic leukocytosis. Urinalysis revealed proteinuria, with a specific gravity of 1.045. The dog was unresponsive to treatment and died. At necropsy, there was severe serofibrinous peritonitis and pleuritis, with randomly scattered dark brown necrotic foci present in multiple organs, including liver, spleen, kidney, and pancreatic lymph node. Histologically, there were extensive regions of parenchymal necrosis surrounded by neutrophils admixed with epithelioid macrophages, lymphocytes, and pigmented fungal organisms. Numerous brown, 2 to 6 microm in diameter, septate, branching hyphae, subsequently identified as Ochroconis gallopavum (formerly Dactylaria constricta var. gallopava), were observed.

Animals↗

Quantitative conditions do not guarantee the validity of the adiabatic approximation.

In this Letter, we point out that the widely used quantitative conditions in the adiabatic theorem are insufficient in that they do not guarantee the validity of the adiabatic approximation. We also reexamine the inconsistency issue raised by Marzlin and Sanders [Phys. Rev. Lett. 93, 160408 (2004)] and elucidate the underlying cause.

Comment↗

Increased growth rate of abdominal aortic aneurysms in women. The Tromsø study.

OBJECTIVES: The present study was undertaken in order to assess the effect of gender on the growth rate of abdominal aortic aneurysms (AAAs). METHODS: One hundred and eighty-five men and 49 women with AAAs were studied, mean follow-up 62 months, giving 14,544 patient-months of follow-up. A mean of 16 ultrasound examinations was performed on each patient. RESULTS: The mean growth rate was 1.82; 1.65 and 2.43 mm per year in men and women, respectively. In a weighted linear regression analysis, high initial diameter and female gender were independent and significant (p < 0.001 and p = 0.003, respectively) predictors for increased growth rate of AAAs. None of the other considered risk factors predicted the growth rate. CONCLUSIONS: This is the first study to report a significantly different growth rate of AAAs in females compared to males. It, thus, adds evidence to the view that AAA is a more malignant condition in females than in males and could have implications for the frequency of follow-up in women.

Aged↗