Search PubMed⌕ Search

Biomedical subjects

R Gupta

Publications and source records attributed to R Gupta.

At least 325 records · Page 18Linked to original sources
PubMed1999

Hypothyroidism presenting as acute cardiac tamponade with viral pericarditis.

This report describes the case of a young woman who presented to an emergency department with severe abdominal pain and shock. The patient was found to have pericardial tamponade due to a massive pericardial effusion. On further evaluation, the etiology of this effusion was considered to be secondary to hypothyroidism with concominant acute viral pericarditis leading to a fulminant tamponade. The presentation, differential diagnosis, and management of pericardial effusion and tamponade secondary to hypothyroidism and viral pericarditis are discussed. The diagnosis of hypothyroidism in conjunction with acute viral pericarditis should be considered in patients presenting with unexplained pericardial effusion and tamponade.

Adult↗
PubMed1999

Antimicrobial resistance among community-acquired pneumonia isolates in Europe: first results from the SENTRY antimicrobial surveillance program 1997. SENTRY Participants Group.

OBJECTIVE: The SENTRY antimicrobial surveillance program was established to monitor the occurrence and antimicrobial susceptibility of bacterial pathogens via an international network of sentinel hospitals. MATERIAL AND METHODS: Microorganisms were forwarded to the reference laboratory for testing against various antimicrobial agents using broth microdilution. Twenty European hospitals referred 286 Streptococcus pneumoniae, 309 Haemophilus influenzae, and 167 Moraxella catarrhalis isolates during the first 10 months of the study, starting in April 1997. RESULTS: Seven percent of the S. pneumoniae isolates were highly resistant to penicillin, and 21% showed intermediate resistance. The highly resistant pneumococcal isolates came from Coimbra, Barcelona, Athens, and London, whereas the intermediate penicillin-resistant isolates were received from all participating countries. The incidence of intermediate penicillin-resistant pneumococci was lowest in Lausanne, Freiburg and Duesseldorf, London, and Utrecht and highest in southern European countries. Fifty-five percent of the penicillin-resistant S. pneumoniae were also resistant to erythromycin, and 35% to clindamycin. Sparfloxacin, trovafloxacin, levofloxacin, and vancomycin were fully active against pneumococcal isolates. Haemophilus influenzae isolates were generally highly susceptible to most of the antibiotics tested, and 92% of the M. catarrhalis isolates were resistant to penicillin. Susceptibility to cephalosporins, ciprofloxacin, levofloxacin, and rifampicin was 100%. CONCLUSION: Penicillin may no longer be the first-choice drug for empirical treatment of pneumococcal infections. The newer fluoroquinolones may play a role in the empirical treatment of community-acquired pneumonia.

Anti-Bacterial Agents↗
PubMed1999

Comparative evaluation of the inflammatory mediators in patients undergoing laparoscopic versus conventional cholecystectomy.

BACKGROUND: Injury induces systemic inflammatory response. The degree of response is proportionate to the trauma. METHODS: Patients with ultrasound-proven gall stones posted for operation were randomized into two groups. Laparoscopic cholecystectomy was performed in one group while the other group underwent conventional cholecystectomy. Peripheral venous blood samples for inflammatory mediators, namely tumour necrosis factor, C-reactive protein, oxygen release from monocytes and polymorphonuclear leucocytes were drawn 1 day before surgery and repeated on the first and third days after surgery. Partial pressure of arterial oxygen was also measured in both groups. Only patients who met selection criteria and had uncomplicated postoperative courses were included in the study. There was a total of 40 patients for the final analysis, 20 in each group. RESULTS: There was no significant difference (P > 0.1) in age, sex or body mass index in both groups of patients. The level of all of the inflammatory mediators was elevated on the first postoperative day; however, the elevation was significantly less following laparoscopic cholecystectomy compared to conventional cholecystectomy (P < 0.01). Although the values came down on the third postoperative day, they remained above the respective controls. Postoperative hypoxaemia was significantly more in patients of conventional than laparoscopic cholecystectomy (P < 0.001). CONCLUSIONS: Trauma-induced inflammatory response is significantly less following laparoscopic cholecystectomy compared to conventional cholecystectomy. It appears to be related to degree of trauma.

Adult↗
PubMed1999

Magnetic resonance evaluation of idiopathic scoliosis: a prospective study.

The objective of the present study was to determine the incidence of unsuspected intraspinal pathology and to assess the value of atypical clinical features as predictors of these intraspinal pathologies, in patients with idiopathic scoliosis. Twenty-five consecutive patients (13 boys, 12 girls) with idiopathic scoliosis were prospectively evaluated with MRI. Magnetic resonance imaging detected intraspinal pathology in seven patients (28%), which included syringohydromyelia with Chiari I malformation (n = 5), and syringomyelia and dumb-bell neurofibromas in one patient each, respectively. Dural ectasia was also present in five patients. Atypical features, described in the literature as pointers to intraspinal pathologies such as the age < 11 years at presentation, presence of pain, hyperkyphosis, severe curves and the presence of the left thoracic or thoracolumbar curves, were seen to be equally distributed between the two groups (those with and without intraspinal pathologies), thus raising doubts about the importance of these features.

Adolescent↗
PubMed1999

The evaluation of tension in an experimental model of external fixation of distal radius fractures.

A cadavaric model was used to evaluate the previously reported methods of determining excessive tension when applying an external fixator across the wrist. An osteotomy of the distal radius was performed and tension was applied incrementally across the joint in 9 cadaveric specimens. The fingers of each specimen could fully flex to the palm at all levels of tension tested. Although the radiocarpal and midcarpal joint spaces did lengthen with incremental changes in the amount of tension, there was no statistically significant correlation that could be made about the difference between the radiocarpal and midcarpal spaces and tension applied across the wrist. Although the carpal height ratio increased significantly from 0 to 10 lb of traction, the carpal height ratio appeared to plateau after further increases in tension. In conclusion, surgeons need to be careful when using any of these previously reported techniques for determining the optimal tension to be applied with an external fixator across the wrist. These techniques may not reproducibly allow the surgeon to detect whether there is excessive distraction across the distal radius fracture.

External Fixators↗
PubMed1999

EEG abnormalities in survivors of neonatal ECMO: its role as a predictor of neurodevelopmental outcome.

The incidence and site of electroencephalogram (EEG) abnormalities and the efficacy of post-ECMO EEG as a predictor of neurodevelopmental outcome was evaluated in survivors of neonatal extracorporeal membrane oxygenation (ECMO). All survivors of neonatal ECMO with an EEG performed prior to their discharge were included if they had at least 12 months of follow-up. The neurodevelopmental outcome was reported as normal, suspect, and abnormal on the basis of neurological examination and the scores on Bayley Scales of Infant Development or McCarthy Scale of Children's Abilities. EEG abnormalities were noted in 31 (70%) of 44 infants. The distribution of EEG abnormalities was not significantly different for right and left hemispheres. The incidence of abnormal neurodevelopmental outcome was similar in infants with a normal or an abnormal EEG (3 of 13 vs. 7 of 31; p = 0.8). EEG abnormalities had no correlation with neurodevelopmental outcome. We conclude that the high incidence of EEG abnormalities and their lack of correlation with neurodevelopmental outcome would suggest that these abnormalities do not represent permanent brain injury and a single EEG performed after decannulation from ECMO is not helpful in identifying infants at risk of subsequent abnormal neurodevelopmental outcome.

Child Development↗
PubMed1999

Acute pancreatitis with cholestatic hepatitis: an unusual manifestation of hepatitis A.

Acute hepatitis A infection is an uncommon cause of pancreatitis in children. To date, only four cases have been reported in the paediatric literature. We report a 7-year-old girl with acute pancreatitis associated with hepatitis A infection who made a satisfactory recovery. The report highlights the CT findings including focal necrosis not previously reported. Because of the extreme rarity of the complication, the four previous reports have also been single case reports. This paper reviews all these cases with a view to elucidating the aetiopathogenesis of the pancreatitis.

Acute Disease↗
PubMed1999

Evaluation of the pituitary gland in idiopathic hypogonadotropic hypogonadism.

PURPOSE: Evaluation of the pituitary gland has been carried out in idiopathic hypogonadotropic hypogonadism (IHH) to test the potential of MR imaging in differentiating IHH patients from normals. MATERIAL AND METHODS: Thirty-seven patients (aged 18-30 years), and 20 volunteers (aged 20-30 years) were studied by T1-weighted MR imaging. Length (LA and LP), height (H), width (W), area (AA and AP), and volume (V1A, V1B V2A, V2P) of the pituitary gland were determined. (Subscripts P and A refer to measurements made with and without the posterior lobe, respectively.) V1 and V2 were estimated using two different methods. RESULTS: In the control group, LB W and V2A exhibited significant differences between female and male volunteers. While W was the only parameter that did not show significant difference between normals and patients (in both men and women), all other parameters except LB H and AP showed statistically significant differences between normals and IHH patients in both males and females. While LP was significantly different between normals and patients (men), H and AP were significantly different between normals and patients only in the female group. CONCLUSION: Correlation analysis between various parameters has shown that LA can be used for evaluating the pituitary in both the male and female IHH patients.

Adolescent↗
PubMed1999

Scanning the available Dictyostelium discoideum proteome for O-linked GlcNAc glycosylation sites using neural networks.

Dictyostelium discoideum has been suggested as a eukaryotic model organism for glycobiology studies. Presently, the characteristics of acceptor sites for the N-acetylglucosaminyl-transferases in Dictyostelium discoideum, which link GlcNAc in an alpha linkage to hydroxyl residues, are largely unknown. This motivates the development of a species specific method for prediction of O-linked GlcNAc glycosylation sites in secreted and membrane proteins of D. discoideum. The method presented here employs a jury of artificial neural networks. These networks were trained to recognize the sequence context and protein surface accessibility in 39 experimentally determined O-alpha-GlcNAc sites found in D. discoideum glycoproteins expressed in vivo. Cross-validation of the data revealed a correlation in which 97% of the glycosylated and nonglycosylated sites were correctly identified. Based on the currently limited data set, an abundant periodicity of two (positions-3, -1, +1, +3, etc.) in Proline residues alternating with hydroxyl amino acids was observed upstream and downstream of the acceptor site. This was a consequence of the spacing of the glycosylated residues themselves which were peculiarly found to be situated only at even positions with respect to each other, indicating that these may be located within beta-strands. The method has been used for a rapid and ranked scan of the fraction of the Dictyostelium proteome available in public databases, remarkably 25-30% of which were predicted glycosylated. The scan revealed acceptor sites in several proteins known experimentally to be O-glycosylated at unmapped sites. The available proteome was classified into functional and cellular compartments to study any preferential patterns of glycosylation. A sequence based prediction server for GlcNAc O-glycosylations in D. discoideum proteins has been made available through the WWW at http://www.cbs.dtu.dk/services/DictyOGlyc/ and via E-mail to DictyOGlyc@cbs.dtu.dk.

Algorithms↗
PubMed1999

A generic mixing system for achieving conditions suitable for single point representative effluent air sampling.

The U.S. EPA has approved Alternate Reference Methodologies for sampling radionuclide aerosol particles from stacks and ducts of U.S. DOE facilities. The approach allows use of single point sampling with shrouded probes from locations where both fluid momentum and contaminant concentration are well mixed across the flow cross section. For existing stacks and ducts that do not have locations where there is adequate mixing, we have developed a generic mixing system that will generate conditions suitable for single point sampling. The coefficients of variation of the velocity, tracer gas, and 10 microm aerodynamic diameter aerosol particles profiles are all less than 10%, which are well within the EPA limit of 20%. Mixing is affected neither by size of the system nor by flow rate, provided the flow is turbulent.

Air Pollution, Radioactive↗
PubMed1999

Suitability of air sampling locations downstream of bends and static mixing elements.

The revised standard for sampling effluent air from stacks and ducts of the nuclear industry places limits on the non-uniformity of velocity and contaminant profiles at the sampling location; namely, the coefficients of variation must not exceed 20% over an area that encompasses at least the center 2/3 of the cross sectional area. Tests were conducted to characterize the degree of mixing at downstream locations as affected by several types of flow disturbances, including 90 degree elbows and commercial static mixing devices. Flow straighteners were incorporated into the ducting upstream of the mixer to be tested to simulate the dampening of flow turbulence that might occur because of upstream HEPA filters. The coefficients of variation of velocity and tracer gas concentration measured in a straight tube at a distance of 3 diameters downstream from a 90 degree elbow were 17% and 69%, respectively. The mixing is impacted by the upstream flow turbulence. Without a flow straightener, the tracer gas concentration coefficient of variation was reduced to 33% at the 3-diameter location. The use of static mixing elements can greatly enhance the mixing process. A ring placed just downstream of a 90 degree elbow, which blocks the outer 56% of the cross sectional area, results in a coefficient of variation of 19% for tracer gas concentration at the 3-diameter location. Pressure loss across the elbow with the ring is about nine times that of the basic elbow. One of the commercially available static mixers provides coefficients of variation that are less than 10% for both velocity and tracer gas concentration at 4 diameters downstream from the mixer with a pressure loss that is only about 3.5 times as large as that of a 90 degree elbow.

Air Pollutants, Radioactive↗
PubMed1999

Novel protein kinases associated with calcineurin B-like calcium sensors in Arabidopsis.

Members of the Arabidopsis calcineurin B-like Ca(2)+ binding protein (AtCBL) family are differentially regulated by stress conditions. One AtCBL plays a role in salt stress; another is implicated in response to other stress signals, including drought, cold, and wounding. In this study, we identified a group of novel protein kinases specifically associated with AtCBL-type Ca(2)+ sensors. In addition to a typical protein kinase domain, they all contain a unique C-terminal region that is both required and sufficient for interaction with the AtCBL-type but not calmodulin-type Ca(2)+ binding proteins from plants. Interactions between the kinases and AtCBLs require micromolar concentrations of Ca(2)+, suggesting that increases in cellular Ca(2)+ concentrations may trigger the formation of AtCBL-kinase complexes in vivo. Unlike most serine/threonine kinases, the AtCBL-interacting kinase efficiently uses Mn(2)+ to Mg(2)+ as a cofactor and may function as a Mn(2)+ binding protein in the cell. These findings link a new type of Ca(2)+ sensors to a group of novel protein kinases, providing the molecular basis for a unique Ca(2)+ signaling machinery in plant cells.

Amino Acid Sequence↗
PubMed1999

Acute pancreatitis associated with viral hepatitis: a report of six cases with review of literature.

Association of hepatitis viruses with acute pancreatitis in the setting of nonfulminant viral hepatitis is rare. We report six cases of nonfulminant viral hepatitis complicated by acute pancreatitis, including the first documented case of hepatitis E virus (HEV) associated acute pancreatitis. The other five patients had acute viral hepatitis caused by hepatitis A infection. Besides features of viral hepatitis, the presence of typical abdominal pain, high serum amylase, and ultrasound or CT scan features suggested the diagnosis of acute pancreatitis. This complication generally developed in the initial phase of the hepatitic illness. All of the patients had mild to moderate pancreatitis that recovered uneventfully with conservative treatment.

Acute Disease↗
PubMed1999

HESX1: a novel gene implicated in a familial form of septo-optic dysplasia.

The homeobox gene Hesx1, which encodes a pituitary transcription factor, is first expressed at gastrulation in the mouse embryo. Hesx1 expression begins in prospective forebrain tissue but later becomes restricted to Rathke's pouch, the primordium of the anterior pituitary gland. Transgenic mice lacking Hesx1 exhibit a phenotype comprising variable anterior CNS defects, such as a reduced prosencephalon, abnormalities in the corpus callosum and septum pellucidum, anophthalmia or microphthalmia, defective olfactory development and bifurcations in Rathke's pouch with pituitary dysplasia. A comparable and highly variable phenotype in humans is septo-optic dysplasia. We have cloned and sequenced the human homologue HESX1 and screened for mutations in affected individuals using single-stranded conformational polymorphism analysis. Two siblings with septo-optic dysplasia were homozygous for a missense mutation within the HESX1 homeobox. This mutation resulted in the substitution of a highly conserved arginine residue (Arg53) by cysteine and led to a loss of in vitro DNA binding. Hence, a vital role for Hesx1/HESX1 in forebrain and pituitary development in mice and humans is suggested.

Animals↗
PubMed1999

Individualised pulse oximetry limits in neonatal intensive care.

AIM: To determine whether individualised limits for arterial oxyhaemaglobin saturation by pulse oximetry (SpO(2)) are more effective for detecting hypoxia and hyperoxia in sick newborn infants than setting fixed limits. METHODS: Six hundred and ninety two simultaneous measurements of SpO(2) and partial pressure of oxygen in arterial blood (PaO(2)) were made in 95 infants. The sensitivity and specificity for predicting hypoxia and hyperoxia using various fixed SpO(2) limits and also individualised SpO(2) limits, calculated using a standard equation, were determined and compared. RESULTS: None of the fixed limits for SpO(2) was both sensitive and specific for predicting hypoxia and/or hyperoxia. There was no difference between these and individualised limits. CONCLUSION: Individualised SpO(2) limits are no more effective than fixed SpO(2) limits for predicting hypoxia and/or hyperoxia in sick newborn infants. SpO(2) monitoring is not an ideal method for assessing PaO(2).

Female↗
PubMed1999

Small pulmonary nodules: evaluation with repeat CT--preliminary experience.

PURPOSE: To assess the use of early repeat computed tomography (CT) of solitary pulmonary nodules to determine nodule growth. MATERIALS AND METHODS: The authors performed repeat CT of nodule phantoms to assess the accuracy of their measurement technique. They then used this technique to assess nodule growth (nine malignant, six benign) in 15 patients (nine men, six women; age range, 60-79 years; average age, 66 years) who underwent repeat CT as part of their routine clinical protocol. The final diagnosis was established with surgical resection or follow-up for more than 2 years after an indeterminate biopsy. RESULTS: Results of phantom experiments revealed that the method used to determine area change is sensitive enough to help detect nodule growth if one pixel is added around the entire circumference of a nodule. With use of standard exponential growth curves and known tumor growth rates, malignant growth could be detected in vivo within 30 days. All 15 in vivo nodules were correctly classified with early repeat CT. CONCLUSION: Preliminary experience with early repeat CT suggests that a single repeat CT scan obtained 30 days after the first scan can depict growth in most malignant tumors as small as 5 mm.

Adenocarcinoma↗