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Biomedical subjects

M Ray

Publications and source records attributed to M Ray.

At least 19 recordsLinked to original sources
PubMed2007

Platelet and leukocyte activation in salvaged blood and the effect of its reinfusion on the circulating blood.

Postoperative wound drainage reinfusion reduces the frequency of homologous blood transfusion. The salvaged blood is depleted of coagulation factors but may contain platelets and leukocytes which are activated, and therefore potentially procoagulant. We ascertained the degree of activation of platelets and leukocytes in salvaged blood and asked whether their infusion produced any measurable effect on patients' coagulation system. We prospectively randomized 24 patients who had total knee arthroplasties to reinfusion of salvaged autologous blood (n = 12) or a standard drain with no reinfusion (n = 12). Analysis of the salvaged blood showed marked activation of platelets as shown by their expression of P-selectin, CD40 ligand, and Factor V/Va, and as increased numbers of platelet-derived microparticles. After reinfusion there was no measurable effect on activation markers of circulating platelets or leukocytes but there was a decrease in platelet count in the reinfused group compared with the control group. Levels of prothrombin fragment F1 + 2 (suggesting thrombin formation) increased in the reinfused group compared with control group, possibly indicating activation of coagulation systemically. The platelets and leukocytes in salvaged blood are markedly activated and their reinfusion causes a decrease in platelet count in the recipient and a possible increase in thrombin generation potentially favoring thrombosis.

Aged↗
PubMed2005

Shaken baby syndrome masquerading as apparent life threatening event.

A variety of diseases and disorders can present as an acute life-threatening event among which shaken baby syndrome has been recently recognized. A high index of suspicion along with an ophthalmologic evaluation and cranial imaging helps to identify this form of child abuse, which needs multidisciplinary management.

Female↗
PubMed2005

Aprotinin and epsilon aminocaproic acid are effective in reducing blood loss after primary total hip arthroplasty--a prospective randomized double-blind placebo-controlled study.

A prospective randomized double-blind placebo-controlled study was undertaken to determine the efficacy and mechanism of action of two antifibrinolytic drugs aprotinin and epsilon aminocaproic acid (EACA) in reducing blood loss in primary unilateral total hip arthroplasty (THA). Aprotinin was administered as a bolus of 2 x 10(6) kallikrein inhibitor units (KIU) followed by 0.5 x 10(6) KIU h(-1) for 3 h, EACA was given as 10 g over 30 min followed by 5 g over 3 h. The median postoperative blood loss 24 h postoperatively was reduced from 450 mL in the placebo group to 180 mL for aprotinin (60% reduction, P < 0.001) and to 210 mL for EACA (53% reduction, P < 0.01). In this population, there was no reduction in the perioperative transfusion requirements. The mechanism of both drugs was independent of platelets as indicated by flow cytometric measurement of change of their expression of P-selectin, platelet-monocyte aggregates, V/Va and CD40 ligand. There were no thrombotic or infective complications and no adverse events were attributable to use of either drug. Infusion of either aprotinin or EACA at the doses described is a safe and effective means of reducing blood loss after THA. These therapies provide a means of reducing blood loss in THA patients.

Aged↗
PubMed2004

Receptor mechanisms involved in the anticonvulsant effect of melatonin in maximal electroshock seizures.

The present study investigates the mechanisms involved in the anticonvulsant effect of melatonin in maximum electroshock (MES) seizures. Melatonin (25-100 mg/kg) dose-dependently decreased the duration of tonic hindlimb extension (THLE). The anticonvulsant effect of melatonin was blocked by bicuculline, a GABA(A) receptor antagonist, and luzindole, an ML(1) receptor antagonist, while prazosin, an ML(2) receptor antagonist, enhanced the anticonvulsant actions of melatonin in this seizure model. Administration of serotonergic agents, mianserin and ondansetron, along with melatonin, increased the antiseizurogenic activity of melatonin, while buspirone had no effect. Pretreating the animals with diazepam, carbamazepine or lamotrigine enhanced the anticonvulsant effect of melatonin. Melatonin thus appears to be an effective anticonvulsant, and melatonin ML(1) receptors, GABAergic and serotonergic mechanisms may play an important role in mediating the anticonvulsant activity of melatonin in electroshock seizures.

Animals↗
PubMed2004

Evaluation of the role of melatonin in formalin-induced pain response in mice.

BACKGROUND: Melatonin, the major secretory product of pineal gland has been suggested to play a regulatory role in the circadian rhythm of body activities including the pain sensitivity. Three subtypes of melatonin receptors, i.e. ML1, ML2 and ML3 have been identified. AIM: To investigate the antinociceptive activity of melatonin and to unravel the underlying receptor mechanisms involved in this action. MATERIAL AND METHODS: Effect of melatonin (25-100 mg/kg, ip) and its interaction with putative melatonin receptor antagonists and opioidergic and serotoninergic agents have been studied in formalin test, a model of tonic continuous pain. Formalin (0.1 ml of 1% solution) was injected under the plantar surface of right hind paw of mice and the time an animal spent in licking the injected paw was measured. STATISTICAL ANALYSIS: The data were analysed by one-way ANOVA followed by Tukey's test for multiple comparisons. RESULTS: Injection of formalin produced two phases of intense licking, an early phase (0-5 min) and a late phase (20-25 min). Melatonin dose-dependently decreased the licking response in both the phases, effect being more marked in the late phase. Luzindole, a ML1 receptor antagonist did not block but rather enhanced the antinociceptive activity of melatonin. However, prazosin, a ML2 receptor antagonist in the low dose (0.5 mg/kg) significantly attenuated but in higher dose (1 mg/kg) enhanced the analgesic effect of melatonin. Naloxone, an opioid receptor antagonist did not reverse but morphine, an opioid agonist enhanced the antinociceptive activity of melatonin. Both mianserin and ondansetron the 5HT2 and 5HT3 receptor antagonists, respectively increased the analgesic effect of melatonin. CONCLUSION: The present results suggest the involvement of ML2 receptors in mediating the antinociceptive activity of melatonin in formalin-induced pain response. Further an interplay between melatonin, alpha-1 adrenergic and 5HT2 and 5HT3 serotoninergic receptors may also be participating in this action.

Animals↗
PubMed2002

Reversible brain lesions in childhood hypertension.

UNLABELLED: Posterior leukoencephalopathy syndrome is characterized by an acute, usually reversible, encephalopathy with transient occipital lobe abnormalities detected on MRI that occur mostly in association with acute hypertension. The clinical presentation includes seizures, headache, altered mental status and blindness. Disturbed autoregulation of cerebral blood flow and endothelial injury are central to the pathogenesis of this disorder. Prompt control of hypertension results in rapid and complete neurological recovery. In this report we discuss the cases of two children with acute onset hypertension of different aetiologies that presented with the characteristic features of posterior leukoencephalopathy syndrome. CONCLUSION: Early recognition of this readily treatable condition may obviate the need for extensive and invasive investigations. Despite the alarming lesions on the MRI, prompt control of hypertension carries a uniformly favourable prognosis.

Acute Disease↗
PubMed2002

Trypan blue assisted phacoemulsification in corneal opacities.

AIM: To evaluate the efficacy of trypan blue for enhancing visualisation during phacoemulsification and foldable lens implantation in cases of cataract with corneal opacities. METHODS: 11 eyes of 11 patients with nebulomacular corneal opacities involving the visual axis with partially and visually debilitating cataract underwent trypan blue assisted phacoemulsification with foldable intraocular lens implantation. The patients were followed at the first day, first week, first month, and third month postoperatively. Completion of capsulorhexis, phacoemulsification with foldable lens implantation, and postoperative best corrected visual acuity were measured. RESULTS: The dye improved visualisation of the anterior capsule and a complete capsulorhexis could be performed successfully in all eyes. In all but one eye phacoemulsification was accomplished successfully. In one eye with Fuchs' dystrophy penetrating keratoplasty was performed later. Visual acuity was < or = 6/60 preoperatively in all eyes and improved to > or = 6/24 in eight eyes postoperatively. CONCLUSION: Trypan blue assisted phacoemulsification may be performed in selected cases of corneal haze/opacification with cataract. It provides acceptable visual outcome in cases awaiting penetrating keratoplasty or in cases where it is not feasible or promising.

Adult↗
PubMed2001

Perinatal tuberculosis.

Perinatal tuberculosis is insufficiently understood. Its early diagnosis is essential but often difficult as the initial manifestations may be delayed. Improved screening of women at risk and sensitivity of the medical community are necessary. A coherent system of cooperation between the hospital and community services and between pediatricians and adult physicians is indispensable to find the index adult case to break the chain of contagion as well as to offer prophylactic therapy to the children at risk. We hereby report a baby with perinatal tuberculosis who was not offered any prophylactic therapy inspite of the mother being diagnosed to have pulmonary tuberculosis.

Adult↗
PubMed2001

Pseudohypoparathyroidism in a mother and son: phenotypic variability and associated disorder.

A 2-month-old infant with clinical features of hypothyroidism presented with hypocalcemic seizures. The maternal phenotypic features aroused the suspicion of pseudohypoparathyroidism which was confirmed in both by biochemical and endocrinological investigations. Though the child had clinical and radiological features to suggest hypothyroidism he had normal free thyroxine and only slightly elevated thyroid stimulating hormone levels. Special note is made of the intra and interpatient variability of this rare inherited disorder.

Adult↗
PubMed2001

Strangulation injury, a fatal form of child abuse.

Strangulation is a common method of committing murder, though underreported in Indian literature. We managed a girl child, victim of child abuse who later succumbed to its neurological complications. This case report describes the clinical features associated with such injuries and complications which should be anticipated in such cases.

Asphyxia↗
PubMed2001

Hyaline membrane disease in a term neonate.

Hyaline membrane disease is primarily a disorder of preterm infants. Its occurrence in term infants is very uncommon and therefore may escape attention. We describe a term infant who developed severe respiratory distress soon after birth. Diagnosis of hyaline membrane disease was revealed at autopsy.

Anti-Bacterial Agents↗
PubMed2001

A population-based eye survey of older adults in a rural district of Rajasthan: II. Outcomes of cataract surgery.

PURPOSE: To assess the outcomes of cataract surgery in rural northwest India. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: A total of 549 cataract-operated persons (723 operated eyes). METHODS: Cluster sampling was used in randomly selecting a cross-sectional sample of persons 50 years of age or older for visual acuity measurement, refraction, and slit-lamp and direct ophthalmoscope examination early in 1999. Those operated on for cataract were queried as to the date and place of surgery. The principal cause of reduced vision was identified for all examined eyes with presenting visual acuity worse than 6/18. MAIN OUTCOME MEASURES: Presenting and best-corrected visual acuity and cause of vision loss. RESULTS: Presenting visual acuity was less than 6/60 in the better eye in 33.7% of cataract-operated persons and greater than or equal to 6/18 in both eyes in 8.2%; 31.7% were bilaterally operated on. Of cataract-operated eyes, 44.1% initially had visual acuity less than 6/60 and 31.5% greater than or equal to 6/18; with best correction, the corresponding percentages were 14.0% and 61.5%. Intracapsular cataract extraction was used in 92% of cases, and 66% had been operated on in surgery camps. Surgical complications were common and a major cause of vision impairment. In multiple logistic regression modeling, female gender and residence in a rural area were associated negatively with both presenting and best-corrected visual acuity outcomes, and surgery conducted before 1990 was associated negatively with best-corrected visual acuity. Place of surgery and subject schooling were not associated with vision outcomes. CONCLUSIONS: Cataract surgery subjects in rural areas of India that are without adequately equipped facilities and skilled surgeons, and lack of availability of intraocular lenses, are not realizing the full sight-restoring potential of modern-day surgery. Emphasis on the quality of cataract surgery outcomes must be increased to keep pace with that being given to increasing surgical volume.

Aged↗
PubMed2001

Oversized corneal grafts for corneal opacities with iridocorneal adhesions.

OBJECTIVE: To evaluate the efficacy of 1-mm oversized corneal grafts in patients with acquired corneal opacities and extensive peripheral iridocorneal adhesions. DESIGN: Prospective noncomparative case series. PARTICIPANTS: Twenty patients (20 eyes) aged 15 years or older with unilateral or bilateral corneal opacification and a shallow anterior chamber. INTERVENTION: Penetrating keratoplasty was performed with donor corneal buttons oversized by 1 mm. MAIN OUTCOME MEASURES: The various parameters evaluated were visual acuity, graft clarity, keratometry, anterior chamber depth, intraocular pressure, and spherical equivalent refraction 12 months after surgery. RESULTS: The keratoplasties were performed in 15 eyes with a corneo-iridic scar after infectious keratitis (75%) and 5 eyes with failed graft (25%). At the final follow-up, a clear graft was achieved in 17 eyes (85%), and 14 eyes (70%) achieved a best-corrected visual acuity of 6/12 or better. Three of the grafts failed because of rejection. The average keratometry was 44.1 +/- 1.0 diopters (D), and the mean spherical equivalent was -3.23 +/- 2.86 D. The oversized grafts provided a mean anterior chamber depth of 2.36 +/- 0.42 mm, and the mean intraocular pressure at the 12 month follow-up was 16.38 +/- 2.09 mmHg. CONCLUSIONS: Corneal grafts oversized by 1 mm provide adequate anterior chamber depth and reduce the risk of peripheral anterior synechiae and secondary glaucoma in patients with corneal opacities and extensive peripheral iridocorneal adhesions.

Adolescent↗
PubMed2001

Identification of a critical lysine residue at the active site in glyceraldehyde-3-phosphate dehydrogenase of Ehrlich ascites carcinoma cell. Comparison with the rabbit muscle enzyme.

The involvement of the lysine residue present at the active site of Ehrlich ascites carcinoma (EAC) cell glyceraldehyde-3-phosphate dehydrogenase (Gra3PDH) was investigated by using the lysine specific reagents trinitrobenzenesulfonic acid (TNBS) and pyridoxal phosphate (PP). Both TNBS and PP inactivated EAC cell Gra3PDH with pseudo-first-order kinetics with the rate dependent on modifier concentration. Kinetic analysis, including a Tsou plot, indicated that both TNBS and PP apparently react with one lysine residue per enzyme molecule. Two of the substrates, d-glyceraldehyde-3-phosphate and NAD, and also NADH, the product and competitive inhibitor, almost completely protected the enzyme from inactivation by TNBS. A comparative study of Gra3PDH of EAC cell and rabbit muscle indicates that the nature of active site of the enzyme is significantly different in these two cells. A double inhibition study using 5,5'-dithiobis(2-nitrobenzoic acid) and TNBS and subsequent reactivation of only the rabbit muscle enzyme by dithiothreitol suggested that a cysteine residue of this enzyme possibly reacts with TNBS. These studies on the other hand, confirm that an essential lysine residue is involved in the catalytic activity of the EAC cell enzyme. This difference in the nature of the active site of EAC cell Gra3PDH that may be related to the high glycolysis of malignant cells has been discussed.

Amino Acid Sequence↗
PubMed2001

Apoptotic changes in cervical intraepithelial neoplasia.

We examined apoptosis in paraffin-embedded archival cervical tissues from cervical intraepithelial neoplasia (CIN) cases to determine whether the apoptotic process is involved in the cellular changes of CIN. Apoptotic bodies, determined by the Tunel method, were largely found at the surface epithelium in a few tissue specimens with no significant abnormality and in most tissues with CIN. Apoptotic bodies were also found within the stratified epithelium of CIN lesions and were altogether absent in specimens with no significant abnormalities. The apoptotic index was significantly associated with the severity of CIN and not with either age or human papillomavirus infection. Based on the findings of increased numbers of apoptotic bodies and their presence within the stratified epithelium in CIN tissues, we hypothesize that dysregulation in the exfoliation of apoptotic cells and resistance towards apoptosis may be prerequisites for the pathogenesis of CIN.

Adult↗
PubMed2001

Resistance to treatment in Kala-azar: speciation of isolates from northeast India.

Kala-azar in India is becoming increasingly difficult to treat, which may be due to the presence of species other than Leishmania donovani; Leishmania tropica was reported to cause the same clinical syndrome in the area. Over the past 3 years, we have collected samples from 241 patients with visceral leishmaniasis from across the region. Of the 189 isolates that grew on diphasic medium, 159 were successfully transferred to liquid medium for typing. Clinically, 80% of these were resistant to antimony. Lipophosphoglycan-specific monoclonal antibodies were used to distinguish the 2 species by agglutination of promastigotes; all 159 were shown to be L. donovani. Eighty-three isolates were confirmed to be L. donovani by isoenzyme analysis, by amplification of kinetoplast DNA, or both, in comparison with multiple reference strains; none were L. tropica. Thus, the rising incidence of clinical resistance to treatment is unlikely to be due to a different species causing kala-azar in north Bihar.

Adolescent↗
PubMed2001

Visual performance of rigid gas permeable contact lenses in patients with corneal opacity.

PURPOSE: To evaluate the visual performance of rigid gas permeable (RGP) contact lenses in patients with nebular and nebulo-macular corneal opacity and correlate the improvement in visual acuity with other visual parameters. METHODS: In a prospective study, visual performance of RGP contact lenses was evaluated in eyes with corneal opacity involving the pupillary area. The baseline visual acuity and other visual parameters with glasses were compared with those recorded with RGP contact lenses. The visual functions evaluated were visual acuity, contrast sensitivity, glare acuity, and mesopic vision. Binocular status with RGP contact lenses was assessed. All patients were followed up for 3 months. RESULTS: Twenty-eight eyes (26 patients) with nebular or nebulo-macular corneal opacity were included in this study. All eyes (100%) achieved significantly better visual performance with RGP contact lenses than with glasses (P< 0.0020). Visual acuity of 6/9 or better was achieved in 50% of patients with RGP contact lenses compared to none with glasses. RGP contact lenses improved the visual acuity by 0.27 decimals over the baseline value with glasses, butthe improvement for mesopic vision and glare acuity was significantly lower at 0.15 and 0.06 decimals respectively. Similarly, contrast sensitivity did not improve to the same extent as visual acuity. Stereopsis was present only in patients with best corrected visual acuity of 6/9 or better with RGP lenses. CONCLUSION: RGP contact lenses improved the visual acuity and other visual performance in patients with reduced vision due to nebular or nebulo-macular corneal opacity. However, contrast sensitivity, glare acuity, and mesopic vision did not improve to the same extent as visual acuity.

Adolescent↗