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Biomedical subjects

N Sharma

Publications and source records attributed to N Sharma.

At least 235 records · Page 13Linked to original sources
PubMed1984

Effect of dietary chronic cadmium exposure on cell-mediated immune response in rhesus monkeys (Macaca mulatta): role of calcium deficiency.

The role of Ca deficiency on the immunomodulatory effects of chronic Cd exposure for a period of 10 weeks in male Rhesus monkeys were assessed by the blastogenic capacity of peripheral blood lymphocytes (PBL) in response to T-cell mitogens, phytohemagglutinin (PHA), and concanavalin A (Con A). Calcium deficiency significantly decreased the blastogenic response to PHA (P less than 0.01) and Con A (P less than 0.05). Although Cd exposure in normal monkeys significantly increased the blastogenic response to Con A (P less than 0.05), Cd exposure in Ca-deficient monkeys produced a further significant decrease in the blastogenic response to Con A (P less than 0.001). Total and ionic Ca were also significantly decreased in plasma of Ca deficient monkeys exposed to Cd. It is possible that these two observations may be related to each other. Thus, it is important to assess the nutritional status of the host while evaluating the immunotoxicological effects of an environmental pollutant.

Animals↗
PubMed1984

Prostaglandins and thromboxane in the delayed phase of shock induced by Serratia marcescens endotoxin.

The cardiovascular and metabolic effects of an endotoxin derived from Serratia marcescens were examined in anaesthetized, spontaneously-breathing cats. There was a marked initial elevation of right atrial pressure (the result of pulmonary vasoconstriction) and decreases in systemic arterial pressure and in arterial PO2. The 'delayed' effects of endotoxin shock in this species (1-8 h) consisted of a reduced cardiac output and decreased urinary excretion. Blood pressure and myocardial contractility (assessed from measurement of left ventricular (LV) dP/dt and LV end-diastolic pressure) were maintained throughout this phase. There was evidence of a metabolic (lactic) acidosis largely compensated by hyperventilation. Plasma levels (both arterial and mixed venous blood samples) of prostaglandin (PG)E2, PGF2 alpha, 6-keto PGF1 alpha and thromboxane (TX)B2 were measured by radioimmunoassay techniques. Endotoxin administration caused substantial increases in the plasma levels of all four derivatives of arachidonic acid, especially between 1 and 6 h. Separation of the endotoxin-treated cats into survivors and non-survivors showed that the non-survivors had significantly higher circulating levels of PGE2, TXB2 and PGF2 alpha. It is suggested that TXB2 and PGF2 alpha might contribute to some of the detrimental effects of endotoxin (e.g. pulmonary, mesenteric, renal vasoconstriction; platelet aggregation with resulting organ failure) and that prostacyclin may be beneficial in endotoxin shock in this species.

Animals↗
PubMed1983

Disulfide linking of albumin to the hinge region of immunoglobulin G in normal human serum.

A protein-protein complex from human serum was isolated and characterized as a two-component system, containing albumin and IgG in a 1:1 mole ratio. The observations reported here suggest that the albumin-IgG complex may have formed through intermolecular disulfide bonds between albumin and IgG. Immunoelectrophoretic analysis of papain-digested fragments of albumin-IgG complex revealed that the combining sites for albumin may be located in the hinge region between the Fab and the Fc fragments of IgG.

Adult↗
PubMed1983

A comparison of liquid-holding recovery and photoreactivation in halophilic and non-halophilic bacteria.

The ability of the extreme halophile Halobacterium cutirubrum to recover from the effects of ultraviolet radiation during liquid holding in the dark in non-nutrient medium has been compared with that of (i) a moderately halophilic bacterium (NRC 41227) and (ii) Escherichia coli B. The photoreactivabilities of all three bacteria have also been studied. The extreme halophile was incapable of liquid-holding recovery in these conditions, in marked contrast to both E. coli B and the moderate halophile, and also failed to recover when held in nutrient medium in the dark. These results strongly support the hypothesis that H. cutirubrum lacks DNA excision repair. It was also found that ultraviolet-irradiated H. cutirubrum could be almost completely photoreactivated from any level of survival in the range 10(-4)-80%, provided exposure to visible light was not delayed, whereas the moderate halophile resembled E. coli B and had a comparatively limited capacity for photoreactivation.

Cell Survival↗
PubMedDate not supplied

Fibular shortening in poliomyelitis.

This study arose from observation that in children will leg shortening from paralysis, the relationship between the tibia and fibula is disturbed. This article analyses 76 patients of post polio residual paralysis involving only one lower limb. Sixteen patients had fibular shortening. Several factors that interfere with fibular growth, i.e. anatomical continuity, soleus strength, abnormal forces at distal fibular physis, result in fibular shortening. Early the age at onset of paralysis, more is the fibular shortening which is associated with lateral wedging of distal tibial epiphysis, valgus at ankle, external torsion of tibia and genu valgus.

Child, Preschool↗
PubMedDate not supplied

Management of posterior capsule tears.

Any breach in the continuity of the posterior capsule is defined as a posterior capsule tear. Posterior capsule tears can be preexisting (congenital or traumatic), spontaneous, or intrasurgical. Preexisting/congenital posterior capsule tears have been related to an intrauterine insult. Posterior capsule tears due to trauma may occur as a consequence of direct mechanical impact due to perforation or blunt injury. Depending on the duration of time between the posterior capsular trauma and the cataract surgery, these posterior capsule tears can have different features. Intrasurgical posterior capsule tears are the most common and can occur during any stage of cataract surgery. Also, they may be planned in the form of primary posterior capsulorhexis. The conventional management consists of prevention of mixture of cortical matter with vitreous, dry aspiration, and anterior vitrectomy, if required. In addition, during phacoemulsification low flow rate, high vacuum, and low ultrasound are advocated if a posterior capsule tear occurs. Dislocated nucleus or nuclear fragments require vitrectomy and the use of perfluorocarbon liquids. In the presence of a posterior capsule tear, the IOL can be placed in the sulcus, if the capsular rim is available, or in the bag, if the tear is small. Scleral fixated posterior chamber lenses and anterior chamber IOLs can be implanted when the posterior capsule tear is large.

Eye Injuries↗
PubMedDate not supplied

Age at menarche in relation to adult body size and physique.

The relationship of early and late menarche with adult body dimensions has been studied on a sample of 147 young adult women drawn from an urban Punjabi population of Chandigarh and Ludhiana. The results indicate that girls with early menarche (age 10 to 11) have significantly smaller skeletal dimensions (both longitudinal and transverse) and more subcutaneous fat than those with average or late menarche. The girls with late menarche have on average more height for weight than early maturers. Results indicate that there is a biological determinant of the observed association between menarcheal age and fatness and adult body size.

Adolescent↗
PubMedDate not supplied

Case-control study of Meige's syndrome. Result of a pilot study.

A pilot case-control study was conducted to identify possible risk factors for Meige's syndrome. Patients with Meige's syndrome and age- and sex-matched controls suffering from other neurological diseases were recruited from the Movement Disorders Clinic and Neurology Outpatient Department of the All India Insititute of Medical Sciences. All participants were interviewed and information regarding psychiatric and medical illnesses, use of medications, exposure to fumes, dust and pets, characteristics such as marital status, socio-economic status, alcohol, tea/coffee use, tobacco use, betel nut chewing and family history of neurodegenerative diseases among first-degree relatives was ascertained. We found that betel nut with tobacco chewing was a significant predictor for Meige's syndrome (adjusted odds ratio 7.4, 95% confidence interval = 1.0-59. 82). The role of local irritation or the effect of some chemicals in tobacco and betel nuts needs further evaluation of the pathogenesis of Meige's syndrome.

Adult↗
PubMedDate not supplied

Epikeratoplasty for keratoconus using manually dissected fresh lenticules: 4-year follow-up.

BACKGROUND: Epikeratoplasty for keratoconus, in the absence of apical scarring, aims at reducing high irregular myopic astigmatism and provides an ectatic cornea with mechanical support. METHODS: We performed epikeratoplasty on 11 keratoconic corneas using fresh or McCarey-Kaufman preserved, manually dissected donor lenticules. A disparity of 0.5 mm was maintained between the host and the donor. Patients with keratoconus having a preoperative spectacle-corrected visual acuity of less than 6/60 and intolerance to contact lens wear were included in this prospective study. Spectacle-corrected visual acuity, keratometry, and refraction were analyzed over a 4-year follow-up period. RESULTS: Four year follow-up was completed on 10 eyes. Of these, 80% achieved a postoperative spectacle-corrected visual acuity of 6/12 or better. Average postoperative keratometry was 45.79 +/- 2.07 D and a decrease of 4.60 +/- 0.09 D was observed in refractive cylinder. Spherical equivalent showed a significant decrease in myopia of -4.35 +/- 0.26 D. Mean time to stabilization was 8 +/- 2.3 weeks. Epithelial defects occurred in three eyes; two were successfully treated by patching. One lenticule was removed due to graft infection following a persistent epithelial defect. CONCLUSION: Epikeratoplasty for keratoconus is a useful procedure with good long-term visual acuity results and an early stabilizing period.

Adolescent↗
PubMedDate not supplied

Ruptured globe 10 years after radial keratotomy.

PURPOSE: To report 3 cases (3 eyes) of globe rupture following blunt trauma 10 to 13 years after radial keratotomy. METHODS: Cases of traumatic ruptured globe after radial keratotomy were reviewed from a tertiary eye care center. One eye underwent therapeutic penetrating keratoplasty, the second was treated with a bandage contact lens, and the third developed retinal detachment leading to phthisis bulbi. RESULTS: Ruptured globes occurred through the keratotomy incision during activities of daily living (1 eye), assault (1 eye), and sports (1 eye). Two eyes regained a visual acuity of 20/30 or better; 1 eye was lost. CONCLUSION: Traumatic rupture of the cornea can occur more than 10 years after radial keratotomy.

Adult↗
PubMedDate not supplied

Polymicrobial keratitis after laser in situ keratomileusis.

PURPOSE: To report a case of polymicrobial infectious keratitis in one eye of a patient who had undergone bilateral simultaneous laser in situ keratomileusis (LASIK). METHODS: A 21-year-old healthy female developed infectious keratitis in her right eye after bilateral LASIK surgery. Material obtained from the infective foci was sent for bacterial and fungal cultures and herpes simplex virus antigen detection, and broad spectrum antimicrobial therapy was instituted. RESULTS: Staphylococcus epidermidis and Fusarium solani were detected on culture and herpes simplex virus antigen was found to be positive. The patient did not respond to medical therapy and subsequently the ulcer perforated. A therapeutic keratoplasty was performed and the final best-corrected visual acuity was 20/40, 1 month after keratoplasty. CONCLUSION: Polymicrobial infectious keratitis, although rare, is a potential sight-threatening complication of LASIK.

Adult↗
PubMedDate not supplied

Petalloid phacoemulsification.

Hard grade IV nuclei are difficult to emulsify without causing additional stress on the zonular apparatus. We herein, describe a method to accomplish successful phacoemulsification in hard cataracts. This technique of "petalloid phacoemulsification" consists of partial central debulking, followed by sequential chopping to create petal-shaped nuclear fragments emanating from the partially debulked center. The rim of the petals are emulsified followed by the emulsification of the central disc and the base of the petal. Twenty eyes with grade IV nuclei underwent uncomplicated petalloid phacoemulsification. The mean phaco time was 1.02 +/- 0.06 minutes and mean percentage endothelial loss was 4.2 +/- 0.8%. Petalloid phacoemulsification is a safe and useful technique in cases of hard cataracts.

Humans↗
PubMedDate not supplied

Massive corneal and conjunctival squamous cell carcinoma.

A patient with massive, protuberant squamous cell carcinoma of conjunctiva invading the whole cornea, so as to hang from the surface, was referred with a visual acuity of hand motion near to face. A microscopically-controlled, frozen section guided excision, followed by double-freeze-thaw cryoapplication to the sclera and the edges of the conjunctival bed and lamello-lamellar sclerokeratoplasty, was performed. Three years later the patient's visual acuity was 20/60 with no evidence of recurrence of the lesion. Frozen section guided excision with adjuvant cryotherapy and lamellar sclerokeratoplasty is a viable therapy for massive squamous cell carcinoma of cornea and conjunctiva.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Effect of renal dysfunction in fulminant hepatic failure.

BACKGROUND: Effect of renal dysfunction in fulminant hepatic failure is not studied extensively. METHODS: Fifty consecutive patients of fulminant hepatic failure were studied prospectively to determine the prevalence of renal failure and its effect on survival. RESULTS: The mean age of these patients was 36 +/- 7.2 years and there were 21 males and 29 females. Twenty two patients (44%) were hepatitis B surface antigen (HBsAg) positive. Renal dysfunction was observed in 19 patients (38%). Acute tubular necrosis was seen in 7 patients (38%) while prerenal azotemia and functional renal failure occurred in six patients each (37%). Renal failure occurred more commonly in patients with jaundice. In these patients it occurred in less than four days and prior to onset of encephalopathy, ascites, and gastrointestinal hemorrhage. Histopathological examination of kidney (done in 8 patients) revealed acute tubular necrosis in 4 patients while patients with functional renal failure and prerenal azotemia had normal histology. A good correlation was observed between biochemical parameters and histology of kidney in all the patients. The survival amongst the patients with FHF was 28% (14 of 50 patients). Poor prognostic indicators were a leukocyte count of more than 16.5 x 10(9)/liter, prothrombin index of less than 34%, a peak serum bilirubin of more than 376 mumol/liter and presence of renal failure. Only 3 of 19 patients with renal failure survived. CONCLUSIONS: Renal dysfunction is a major indicator of poor prognosis in patients with FHF.

Acute Kidney Injury↗
PubMedDate not supplied

Abdominal hydatids: a minimally invasive approach.

BACKGROUND: The conventional surgical procedures for managing abdominal hydatids, including those of the liver, have a very high morbidity rate in terms of hospital stay and wound complications. Less invasive procedures may thus be logical alternatives. METHOD: We enrolled 58 patients in the study. Using guided ultrasound aspiration followed by instillation of 15% saline, we were able to manage 16 patients as outpatients. In the remaining 42 patients, saline instillation was combined with laparoscopic aided percutaneous evacuation combined with partial pericystectomy. Omental packing was added in four patients. A pericystic drain tube was left in every patient managed laparoscopically. RESULTS: In the aspiration group, two sittings were required in 12 patients and more than two sittings (3 x) in two patients. Laparoscopic parameters showed an average IV infusion time of 12.3 hrs, drain removal time of 3.2 days, and discharge time of 3.2 days. Short-term complications included prolonged tube drainage for six days in one patient, intracystic bile collection in two, and intracystic pus in four patients. The aspiration group did not have any complications. Conversion to open evacuation was done in one patient. Fifty-four months of follow-up has been recurrence free. CONCLUSION: Minimally invasive management, including aspiration and laparoscopic intervention, appear to be viable alternatives to open surgery because they result in less morbidity.

Abdomen↗
PubMedDate not supplied

Sinus fracture--phacoemulsification technique for dense cataracts.

A method of performing phacofracture of hard nuclei is presented. Following a central horizontal fracture into 2 hemisections, the phacoprobe is plunged into the inferior hemisection to create a sinus within its dense wall. The chopper/second instrument is placed into the sinus and force is applied along the lateral walls of the sinus. The phacoemulsification probe breaks it and splits the inferior hemisection into two quadrants. A similar method is employed for the superior-nuclear hemisection.

Cataract↗
PubMedDate not supplied

Pheochromocytoma: a 10-year experience in a tertiary care North Indian hospital.

BACKGROUND: The study was carried out to highlight the clinical and biochemical profile of patients with pheochromocytoma in a tertiary care center of North India. METHODS AND RESULTS: Thirty consecutive cases of pheochromocytoma admitted over a period of 10 years to our Institute were analyzed. The chief clinical complaints of these 30 patients (17 males and 13 females, mean age 24+/-7 years) were palpitation (80%), headache (77%), sweating (60%), breathlessness (67%) and flushing (56%). The clinical triad of headache, flushing and sweating occurred in 26.7% of cases. On clinical examination, 97% of the patients were hypertensive and 16.6% presented with malignant hypertension. Laboratory measurements showed that the levels of 24-hour urinary vanillylmandelic acid were elevated in 80% of cases. Levels of plasma adrenaline and noradrenaline were raised in 78% and 79% of cases, respectively. Anatomical localization of the tumor on computerized tomographic scan showed the presence of an adrenal tumor in 80% and extra-adrenal tumor in 20%. Surgical removal of the tumor could be carried out in 28 cases following control of the blood pressure with antihypertensive drugs including alpha and beta adrenoreceptor blockers. CONCLUSIONS: Pheochromocytoma should be suspected in all young hypertensive persons. The appropriate therapy for this tumor is surgical removal preceded by adequate blood pressure control including the use of alpha and beta adrenoreceptor antagonists.

Adolescent↗