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Biomedical subjects

S Sharma

Publications and source records attributed to S Sharma.

At least 865 records · Page 48Linked to original sources
PubMed1994

Percutaneous transvenous mitral commissurotomy in 390 cases using the Inoue balloon catheter.

Percutaneous transvenous mitral commissurotomy using the Inoue technique was performed in 390 cases of rheumatic mitral stenosis. There were 220 (56%) females and 170 (44%) males. The age range was 9-47 years [mean +/- S.D., 26 +/- 14) and all were symptomatic (New York Heart Association (NYHA) class II in 23 (6%); class III in 280 (72%); and class IV in 87 (22%) patients]. Mitral valve area increased from 0.6 +/- 0.4 to 2 +/- 0.7 cm2, mean transmitral gradients decreased from 26 +/- 8 to 5 +/- 3 mmHg and cardiac index improved from 2.2 +/- 0.8 to 3.0 +/- 0.7 l/min/m2 (P < 0.001). There were no procedure related deaths. An increase in mitral regurgitation by one grade was observed in 40 (10%) cases, with 8 (2%) cases developing severe mitral regurgitation. Oximetry evidence of left to right atrial shunt (Qp/Qs > or = 1.5:1) was observed in 11 (3%) patients. Four (1.0%) patients developed cardiac tamponade, none had thromboembolism. Follow-up of 290 cases at 26 +/- 5 weeks showed persistent improvement in clinical (NYHA class I in 98%) and echocardiographic mitral valve area. Percutaneous transvenous mitral commissurotomy is safe, easy to perform and provides excellent clinical and hemodynamic benefit in the majority of cases.

Adult↗
PubMed1994

Transient myocardial dysfunction in a patient with subarachnoid haemorrhage.

We report a patient of subarachnoid haemorrhage who presented with severe left ventricular dysfunction and marked electrocardiographic changes indistinguishable from acute myocardial infarction. Coronary arteriography showed normal anatomy and the ventricular regional wall motion abnormalities recovered spontaneously after 3 weeks. The implications of this association are discussed.

Coronary Angiography↗
PubMed1994

Remote sensing of atmospheric aerosol in the nocturnal boundary layer using lidar.

This paper presents the results of the lidar experiments that have been performed during January 1989 through August 1990 to study the aerosol vertical distributions in the nocturnal atmosphere and their comparison with near-simultaneous aerological soundings for environmental monitoring. During the study period, the aerosol distributions showed significant stratified aerosol layer structures in the lower atmosphere throughout the south-west monsoon season (June-September), while these structures appear to be either erratic or absent during remaining months of the year. In addition, the aerosols present in the lowest air layers up to 200 m are found to contribute significantly (about 40%) to the aerosol loading in the nocturnal boundary layer at the lidar site. The pre-monsoon to winter ratio of mixing depth and ventilation coefficient were found to be 1.11 and 1.62, respectively. Thus the height of the mixed layer (around 350 m) and the associated ventilation coefficients suggest that early winter evenings tend to have higher pollution potential at the experimental site. The results indicate that the lidar technique has the potential to yield good information on the structure of the nocturnal atmosphere which is found to be influenced by the atmospheric stability conditions as revealed by aerological observations.

Journal Article↗
PubMed1994

The augmentation of leucocyte adhesion to endothelium by therapeutic ultrasound.

To determine the effects of exposure of endothelial cells to therapeutic ultrasound on leucocyte adhesion to these cells, confluent cultures of bovine aortic endothelial cells in tissue culture flasks and on collagen coated coverslips were exposed to a maximum of 1.6 W/cm2 1 MHz continuous ultrasound for 15 min, then incubated with neutrophil-rich suspensions containing a known number of viable human leucocytes for intervals from 1 to 240 min. After incubation, nonadherent cells were decanted, the number of leucocytes in the eluted suspension determined and the percentage of adhered cells calculated. Endothelial cell viability was not significantly reduced by ultrasound or by incubation with leucocytes. Whereas untreated endothelial cells were flattened and had surface microvilli, those exposed to ultrasound were plump, rounded and more widely separated along their borders. The percentage of leucocytes that adhered to sonicated endothelium was significantly higher, and this proportion increased with the duration of incubation. Thus, exposure of endothelial cells to ultrasound in vitro can cause intercellular separation and increase the adhesion to leucocytes. If such changes were also to occur in vivo, therapeutic ultrasound would potentiate the inflammatory response.

Animals↗
PubMed1994

Early and simple determination of chorionic and amniotic type in multifetal gestations in the first fourteen weeks by high-frequency transvaginal ultrasonography.

OBJECTIVE: Our aim was to determine the chorionic and amniotic types in multifetal pregnancies with transvaginal ultrasonography at > or = 14 weeks' gestation. STUDY DESIGN: Two hundred twelve multifetal pregnancies were scanned transvaginally at or before 14 weeks' gestation. The number of fetuses and the chorionic and amniotic type were determined ultrasonographically. Of the 212 patients, 54 were delivered at our institution, and 43 of these 54 had pathologic evaluation of the placenta. Ultrasonographic and pathologic correlation of the chorionic and amniotic type was assessed in this group. RESULTS: Ultrasonographic evaluation of the 212 pregnancies demonstrated 64 twin, 87 triplet, 41 quadruplet, 18 quintuplet, 1 sextuplet, and 1 septuplet gestation. Nine of the twin pregnancies were monochorionic-diamniotic; two of the triplets were dichorionic-triamniotic, and four of the quadruplets were trichorionic-quadraamniotic. In the 43 patients with both ultrasonographic and pathologic assessment, there were 40 twins, five of which were monochoronic diamniotic type. All three triplets were trichorionic-triamniotic type. In all 43 transvaginal ultrasonography correctly predicted the chorionic and amniotic type as determined by the pathologic findings. CONCLUSIONS: Transvaginal ultrasonography at < or = 14 weeks can easily and accurately determine the chorionic and amniotic type in multifetal pregnancies.

Amnion↗
PubMed1994

Life-threatening arterial haemorrhage: results of treatment by transcatheter embolization using home-made steel coils.

Major arterial haemorrhage can be fatal. Its management by percutaneous embolization using commercially available embolizing agents is well established. We describe the use of home-made steel coils in the treatment of five patients. These coils were designed during the procedure in order to conform to the dimension of the bleeding artery. The group included two patients with life-threatening haemoptysis after surgical correction for tetralogy of Fallot; one patient each with exsanguinating haemorrhage from a branch of the left profunda femoral artery following violent trauma; massive haematuria due to an inoperable hypernephroma; and haemoptysis due to post-tubercular bronchiectasis. The bleeding vessel was evaluated by selective angiography in each patient. After assessing its length and diameter, steel coils of desired dimensions were made by utilizing a conventional 0.032-in wide guidewire and these were released into the bleeding artery. Occlusion of the bleeding vessel was obtained in all patients, without complication. Fabrication of coils of desired length and diameter can be done within a few minutes during the procedure. These coils provide an effective method of treating life-threatening arterial haemorrhage in selected cases.

Adult↗
PubMed1994

Antifertility effects of aqueous extract of Carica papaya seeds in male rats.

The influence of the crude aqueous extract of Carica papaya L. (Caricaceae) seeds has been studied on semen profile, fertility, body and organ weight response, and toxicology in male albino rats. The extract was administered at the dose regimens of 10 and 50 mg/animal/day orally for 30, 60, and 90 days and 0.1 and 1.0 mg/animal/day intramuscularly for 15 and 30 days. Cauda epididymal sperm motility and count was reduced significantly at low and high dose regimens both in the oral as well as the intramuscular groups. The reduced sperm motility was associated with morphological defects. Testicular sperm counts were also reduced in all the treatment groups except the low dose intramuscular group. Fertility tests showed dose- and duration-dependent reduction and zero fertility was observed at high dose regimens of the oral and intramuscular groups following 60 and 30 days of treatment, respectively. Testicular weight was reduced in all the treatment groups, whereas accessory sex organs showed a variable response. Body weight and toxicological observations did not show any untoward response. Fertility and all other associated changes returned to normal within 45 and 30 days of treatment cessation in the oral and intramuscular groups, respectively. The data revealed that reversible sterility could be induced in male rats by papaya seeds aqueous extract treatment without adverse effects on libido and toxicological profile.

Animals↗
PubMed1994

Extra gonadal germ cell tumours: report of two cases.

Extra gonadal germ cell tumours (EGGCT) in women are rare. We report here two such patients. The clinical and laboratory features were--young age, 25 and 22 years, midline location (mediastinum, scalp), elevated tumour marker and normal ovaries on CAT scan. The histological subtype was embryonal carcinoma in both cases. Complete response (CR) was achieved with cisplatin based chemotherapy (CT). Both patients had return of normal ovarian functions and have delivered normal babies (1st patient one, 2nd patient 2 babies). Both remain asymptomatic and disease-free at 30 + and 55 + months follow-up. We conclude that patients with EGGCT after treatment with cisplatin based CT achieve CR with return of normal ovarian functions and prolonged survival.

Adult↗
PubMed1994

Anti-inflammatory and bronchodilator properties of RP 73401, a novel and selective phosphodiesterase type IV inhibitor.

1. We have investigated the effects of RP 73401, a novel, potent and highly selective cyclic nucleotide phosphodiesterase (PDE) type IV inhibitor, in guinea-pig and rat models of bronchoconstriction and allergic inflammation. In some models, the effects of RP 73401 have been compared with those of the standard PDE type IV inhibitor, rolipram. 2. RP 73401 (0.4-400 micrograms kg-1, intratracheally (i.t.) on lactose) inhibited antigen-induced bronchospasm in previously sensitized conscious guinea-pigs (ID50: 7 +/- 1 micrograms kg-1) and in anaesthetized rats (ID50: 100 +/- 25 micrograms kg-1). Rolipram inhibited the antigen-induced bronchospasm in guinea-pigs with an ID50 of 5 +/- 1 micrograms kg-1. In guinea-pig bronchoalveolar lavage (BAL) fluid, total inflammatory cell and eosinophil numbers were reduced by RP 73401 (ID50s: 3.9 +/- 0.8 micrograms kg-1 and 3.2 +/- 0.7 micrograms kg-1, respectively). In the rat, inflammatory cell numbers are less affected. Only the highest dose of RP 73401 (400 micrograms kg-1) significantly inhibited eosinophil influx (41 +/- 16% inhibition). 3. RP 73401 (0.02-100 micrograms kg-1, i.v.) inhibited PAF-induced bronchial hyperreactivity to bombesin in the anaesthetized guinea-pig (ID50: 0.09 +/- 0.03 micrograms kg-1) and inhibited (0.4-40 micrograms kg-1, i.t.) histamine-induced airway microvascular leakage in the anaesthetized guinea-pig by approximately 60% at all doses. 4. RP 73401 relaxed guinea-pig isolated trachea under basal tone (EC50: 9 nM) and when precontracted with histamine (IC50: 2 nM), methacholine (IC50: 29 nM) or leukotriene D4 (LTD4, IC50: 4 nM). 5. RP 73401 (0.4-100 microg kg-1, i.t.) inhibited bronchospasm induced by histamine (ID.%: 34 +/- 6 microg kg-1), methacholine (ID50: 66 +/- 12 pg kg-1) and LTD4 (ID50: <4 microg kg-1) in the anaesthetized guinea pig.Against these same bronchoconstrictors, rolipram (i.t.) had ID5o values of 44 +/- 4, 72 +/- 18 and<4 pg kg- respectively. RP 73401 (4 and 40 pg kg-, i.t.) increased the magnitude and duration of bronchodilatation produced by salbutamol in the anaesthetized guinea-pig. At doses producing significant bronchodilatation, RP 73401 was without effect on heart rate or blood pressure in the anaesthetized guinea-pig. RP 73401 (0.01 -0.25 mg kg-1, i.v.) did not affect heart rate and produced only a small fall in blood pressure in the anaesthetized rat.6. These data demonstrate that RP 73401 and rolipram inhibit antigen- and mediator-induced bronchospasmin guinea-pigs with the same potency. Furthermore, RP 73401 administered directly into the airways, protects against allergic airway inflammation. These results indicate the importance of PDE IV in regulating smooth muscle and inflammatory cell activity. At doses suppressing the inflammatory response in the lung, RP 73401 had little effect in the cardiovascular system. RP 73401 may have a role as a bronchodilator and, more importantly, as a prophylactic anti-inflammatory agent in the treatment of asthma.

Albuterol↗
PubMed1994

Anti-complement activity of oleanolic acid: an inhibitor of C3-convertase of the classical complement pathway.

Oleanolic acid is a naturally occurring compound, isolated from Luffa cylindrica, which inhibits the in-vitro immunohaemolysis of antibody-coated sheep erythrocytes by guinea-pig serum. In further experiments this reduced immunohaemolysis was found to be due to inhibition of the C3-convertase of the classical complement pathway. The threshold concentration for inhibition of C3-convertase was 100 micrograms mL-1. However, higher concentrations of oleanolic acid showed constant inhibitory effects on immunohaemolysis. Oleanolic acid also exhibited weak inhibitory effects on individual components of the complement system.

Animals↗
PubMed1994

Effects of ciprofloxacin, norfloxacin, and ofloxacin on in vitro adhesion and survival of Pseudomonas aeruginosa AK1 on urinary catheters.

Pretreatment of urinary silicone latex catheters in vitro with 0.1 and 0.5 microgram of ciprofloxacin per ml for 1, 24, and 48 h significantly reduced the adhesion and survival of the clinical isolate Pseudomonas aeruginosa AK1. UV spectroscopy and high-performance liquid chromatography confirmed the presence of ciprofloxacin adsorbed onto the catheters and showed that up to 56% of the drug leached into the surrounding fluid within 24 h. Scanning electron microscopy demonstrated that the adherent organisms were malformed and elongated after exposure to ciprofloxacin. Transmission electron microscopy showed the presence of fimbriae on the bacterial surfaces, but there was no conclusive evidence of changes in the fimbriae upon exposure to ciprofloxacin. It was found that a significant eradication of 24-h Pseudomonas biofilms could be achieved with ciprofloxacin as well as with ofloxacin and norfloxacin. Preincubation of catheters with 50- and 100-micrograms/ml concentrations of ciprofloxacin resulted in up to a 99% reduction in the number of adherent bacteria in comparison with the reduction on control catheters. In addition, adherent biofilms were eradicated by 24 h of challenge with 50 and 100 micrograms of ciprofloxacin per ml at pH 7.0 and 5.5. Results of these in vitro studies suggest that there could be a clinical role for fluoroquinolones in preventing and treating urinary tract infections associated with P. aeruginosa adherence to prosthetic devices.

Anti-Infective Agents↗
PubMed1994

Novel proteins of Plasmodium falciparum identified by differential immunoscreening using immune and patient sera.

A differential serological screen of a lambda gt11 cDNA expression library of Plasmodium falciparum was performed in an attempt to identify novel and putative host-protective antigens of the parasite. The screening was done with two categories of sera: (i) acute-phase sera obtained from smear-positive acutely infected P. falciparum patients from various regions in India and (ii) immune sera taken from healthy, permanent adult residents of P. falciparum-endemic rural districts of Orissa in eastern India. These adults had not suffered from any clinical malarial symptoms for at least the previous 3 years at the time of serum collection. Sixty-five clones obtained by screening the lambda gt11 library with two immune serum samples were analyzed extensively with a total of 70 acutely infected patient serum samples. Eight of these clones failed to react with any of the patient sera. Each of these eight clones, when tested individually with 92 serum samples from the immune group, reacted with a minimum of 43% of the samples from this category of sera. Thus, these eight epitopes may encode host-protective elements since they are not recognized by antibodies in the patient sera but react exclusively and extensively with the clinically immune set. Sequence analysis of two of these clones reveals that they are novel Plasmodium genes.

Adult↗
PubMed1994

Growth phase-dependent transcription of the genes that encode the two methyl coenzyme M reductase isoenzymes and N5-methyltetrahydromethanopterin:coenzyme M methyltransferase in Methanobacterium thermoautotrophicum delta H.

The genes encoding the two isoenzymes of methyl coenzyme M reductase (MRI and MRII) in Methanobacterium thermoautotrophicum delta H have been cloned and sequenced. The MRI-encoding mcr operon (mcrBDCGA) has been located immediately upstream from the mtr operon (mtrEDCBA) that encodes N5-methyltetrahydromethanopterin:coenzyme M methyltransferase, the enzyme that catalyzes the step preceding the MR-catalyzed reaction in methanogenesis. The MRII-encoding mrt operon (mrtBDGA) has been located between the operon that encodes the methyl viologen-reducing hydrogenase and an open reading frame (designated pyrC) predicted to encode dihydroorotase. Surprisingly, the mrt operon has been found to contain only four genes (mrtBDGA), lacking the equivalent of the mcrC gene that is present in all mcr operons. A protocol that isolates transcripts intact from M. thermoautotrophicum delta H cells has been developed and used, with primer extension and Northern (RNA) blot procedures, to identify the sites of transcription initiation upstream of the mcr, mrt, and mtr operons and to determine the relative numbers of these transcripts in cells at different growth stages. Transcription of the mrt operon was found to occur only at early times in batch cultures and was then replaced by transcription of the mcr operon. Transcripts of the mtr operon were detectable at all times; however, at early times, all mtr transcripts were initiated at the mtr promoter, whereas at later times, during mcr transcription, approximately 3% of mcr transcripts were extended to generate mcr plus mtr transcripts that constituted approximately 20% of all mtr transcripts present.

Amino Acid Sequence↗
PubMed1994

A central role for Fos in human B- and T-cell NFAT (nuclear factor of activated T cells): an acidic region is required for in vitro assembly.

Nuclear factor of activated T cells (NFAT) is a multicomponent transcription factor that contains Fos and Jun family proteins in addition to a constitutively expressed factor(s). It is important for the production of interleukin 2 (IL-2) by T cells and is also expressed in B cells. Here we show that NFAT complexes in B- and T-cell nuclear extracts can be supershifted prominently with Fos antibodies and to a variable extent with Jun family protein antibodies. Fos and Jun proteins appear to participate in NFAT complexes as heterodimers, since efficient in vitro reconstitution of NFAT in unstimulated B- or T-cell nuclear extracts required both Fos and Jun. Using Fos and Jun deletion derivatives, we found that an acidic Fos region (amino acids 118 to 138), outside the DNA binding and dimerization domains, was necessary for the in vitro reconstitution of the NFAT complex in both B- and T-lymphocyte extracts although it was not required for binding to an AP-1 site. Fos-Jun heterodimers exhibited low-affinity direct binding to the NFAT site in the absence of nuclear extracts. This binding also required the Fos acidic region, amino acids 118 to 138. Mutating a variant AP-1 site in the NFAT oligonucleotide abolished both direct binding of Fos-Jun heterodimers and in vitro reconstitution of NFAT. These results demonstrate a central role of Fos in NFAT complex formation in both B and T lymphocytes and show that NFAT assembly involves direct binding of Fos-Jun heterodimers to a variant AP-1 site within the human NFAT recognition site.

B-Lymphocytes↗
PubMed1994

Clinical predictors of Japanese encephalitis.

Over a 5-year period, virological investigations for Japanese encephalitis (JE) were conducted in children presenting with acute encephalopathic illness. Clinical features of JE-positive patients (n = 116) were compared with patients in whom the diagnosis could be excluded (n = 57). Multivariate analysis by logistic regression revealed that two clinical signs--central hyperpneic breathing pattern and extrapyramidal signs--were significant predictors of the diagnosis. Application of the model yielded a sensitivity of 41.3% and a specificity of 80.7% with positive and negative predictive values of 81.3 and 40.3%, respectively. This indicates that the model may be helpful in making the diagnosis but not in excluding it. The model should be further validated in different areas where the disease is prevalent.

Child↗
PubMed1994

Combined radiotherapeutic and surgical management of a spinal cord compression by extramedullary hematopoiesis in a patient with hemoglobin E beta-thalassemia.

A 22-year-old male with a history of hemoglobin E beta zero-thalassemia presented with thoracic spinal cord compression due to extramedullary hematopoietic tissue in the epidural space. Following decompressive laminectomy, this epidural mass was irradiated to 20.4 Gy in 12 fractions. The patient made a complete recovery from his neurological symptoms following treatment. Follow-up radiographs showed significant reductions in size of the extradural tumor. Results from this case supported by review of the literature suggest that radiation therapy, with or without decompressive surgery, is an effective therapy in treatment of patients with spinal cord compression due to epidural extramedullary hematopoietic tissue.

Adult↗