Search PubMed⌕ Search

Biomedical subjects

S Singh

Publications and source records attributed to S Singh.

At least 253 records · Page 14Linked to original sources
PubMed2001

Serum amyloid P-component-induced colony-stimulating factors production by macrophages.

Purified mouse serum amyloid P-component (SAP; 0.5-50 microg/kg), injected intravenously into Swiss mice, induced the production of serum colony-stimulating factors (CSFs); the maximum induction was observed at 10.0 microg/kg. Further, in vitro purified mouse SAP (0.1-50 microg/ml) stimulated the mouse elicited peritoneal macrophages to elaborate CSFs in the conditioned medium (CM); 5.0 microg/ml SAP appeared to be the optimum. Both in vivo and in vitro the maximum production of CSFs occurred 6 h after initiation of stimulation, and returned to the background levels by 48 h. Mannose 6-P, mannose 1-P and mannose, and not other sugars inhibited the SAP-induced production of CSFs by macrophages which suggests that SAP interaction with macrophages was mediated by specific glycoprotein-receptors. A neutralizing (100%) concentration of rabbit antimouse interleukin (IL)-1 polyclonal antibody had no effect on the SAP-induced CSF production, indicating that it would be IL-1-independent. SAP-induced CSFs, both in serum and CM, were functionally similar as they supported the formation of granulocyte (G), macrophage (M) and GM colonies in similar proportions. The production of CSFs appeared to be lipopolysaccharide (LPS)-independent as it was not inhibited by polymyxin B sulfate (25.0 microg/ml), and heat-inactivated (80 degrees C, 1 h, pH 7.0) SAP did not induce the production of CSFs. The CSFs were produced de novo because cycloheximide (50.0 microg/ml) completely inhibited their production. These results demonstrate that purified mouse SAP, in a dose-dependent manner, can induce the production of serum CSFs in mice, and can induce LPS-independent de novo production of CSFs by elicited macrophages in vitro.

Acute-Phase Reaction↗
PubMed2001

Magnetic resonance imaging signal characteristics in hydatid cysts.

The MRI features of hydatid cysts were retrospectively studied in 12 patients to look for specific signal characteristics. Twelve patients in the series included eight with abdominal, two with abdominal-pelvic, one with a sacral and one with a lung hydatid cyst. The T1-, T2- and proton density (PD)-weighted images of spin-echo sequence were used for imaging. The signal characteristics of the hydatid parent cyst capsule and fluid, daughter cyst fluid, detached germinal membrane and surrounding soft tissue reaction were noted. Observations revealed that the capsule is best seen on T2- and PD-weighted images. The daughter cysts are best demonstrated on T1-weighted images, whereas the difference in the signal intensities of parent cyst and daughter cyst fluid is better demonstrated on T2-weighted and T1-weighted images, and the detached germinal membrane is best seen on T2- and PD-weighted images. The signal characteristics of hydatid cyst morphology can help distinguish it from other entities.

Abdomen↗
PubMed2001

Pituitary tuberculoma mimicking adenoma: magnetic resonance imaging.

A case of a pituitary mass with clinical and MRI findings consistent with adenoma is presented. Transnasal transphenoidal excision biopsy showed it to be a pituitary tuberculoma. The patient was treated with antituberculous drugs, and a follow-up MRI 18 months later showed good response. MRI features and a review of published reports of the sellar tuberculoma are briefly discussed.

Adenoma↗
PubMed2001

Squamous cell carcinoma arising from a congenital duplication cyst of the esophagus in a young adult.

Squamous cell carcinomas arising from the congenital anomalies in the esophagus are rare. One such case of an 18-year-old man, with an associated history of ventricular septal defect, who developed an epithelial malignancy within the duplication cyst extending to involve the lower third of esophagus is presented here. He responded well to radical treatment using concurrent chemo-irradiation, and continues to be free of disease after a follow-up of 14 months.

Abnormalities, Multiple↗
PubMed2001

NPB-75: A portable quantitative microstream capnometer.

A portable quantitative microstream capnometer (NPB-75) was tested in intubated children. The end-tidal CO(2) values measured by this device showed good agreement with concomitantly measured values of a stationary mainstream capnometer (N-6000). This lightweight device, with a 4-hour battery life, graphic capnogram display, and audiovisual alarms is well suited for the prehospital setting.

Age Factors↗
PubMed2001

An evaluation of Polaroid photographic imaging for cutaneous-lesion referrals to an outpatient clinic: a pilot study.

A pilot study consisted of 65 patient referrals to a Regional Plastic Surgery Department in which the referral letter, accompanied by a high-quality Polaroid photograph, was assessed by four consultants. The diagnosis, degree of urgency of treatment, grade of surgeon (to undertake the operation) and anticipated time for the procedure were recorded. The results were statistically analysed. Our aim was to evaluate the diagnostic accuracy and consistency of the four observers. The majority of malignant skin lesions were detected accurately; those that were missed received urgent attention due to a high degree of suspicion. This study supports the view that 'triage' of referrals using high-quality photographic images in association with an accurate referral letter can offer a significant reduction in pressure on waiting time and inconvenience for patients by avoiding an additional outpatient visit. Advantages to purchasers in terms of cost savings on outpatient visits and travelling reimbursement can result from this initiative.

Algorithms↗
PubMed2001

Serum lipase, C-reactive protein, and interleukin-6 levels in ERCP-induced pancreatitis.

BACKGROUND: C-reactive protein (CRP) and interleukin-6 (IL-6) are elevated in acute pancreatitis. Limited studies have evaluated their role in ERCP-induced pancreatitis. The aim of this study was to assess the role of serum lipase, CRP, and IL-6 in ERCP-induced pancreatitis. METHODS: Eighty-five patients (62 women, 23 men; mean age 43 years; range 16-85 years) who underwent ERCP were entered in a prospective trial. ERCP-induced pancreatitis was classified as mild, moderate, or severe. Serum levels of lipase, CRP, and IL-6 were measured before ERCP and at 12 to 24 hours and 36 to 48 hours after ERCP. RESULTS: Mild, moderate, and severe pancreatitis occurred, respectively, in 9, 7, and 4 patients after ERCP. There were significant differences in levels of CRP and IL-6 but not lipase for patients with mild versus moderate and moderate versus severe pancreatitis. The mean CRP levels (mg/dL) at 12 to 24 hours were 0.98 +/- 0.24 in mild pancreatitis, 3.89 +/- 0.32 in moderate pancreatitis, and 12.0 +/- 1.60 in severe pancreatitis. The levels, respectively, at 36 to 48 hours were 1.60 +/- 0.31, 7.60 +/- 0.74, and 25.0 +/- 2.9. The mean IL-6 levels (pg/mL) at 12 to 24 hours were 16.6 +/- 2.06 in mild pancreatitis, 73.0 +/- 15.60 in moderate pancreatitis, and 235.5 +/- 26.31 in severe pancreatitis. The levels at 36 to 48 hours were, respectively, 18.92 +/- 3.28, 100.17 +/- 11.56, and 438.2 +/- 71.50. CONCLUSIONS: Serum CRP and IL-6 levels may be useful early markers for predicting the severity of ERCP-induced pancreatitis.

Acute Disease↗
PubMed2001

Sera from lupus patients inhibit growth of P. falciparum in culture.

A large number of malaria immune persons from Eastern India were found to possess antibodies to the ribosomal phosphoprotein P0 (PfP0) of the human malarial parasite Plasmodium falciparum. The characterization of PfP0 has been reported recently, and it has been shown that antibodies against PfP0 inhibit P. falciparum in vitro. About 10-15% of the patients suffering from the autoimmune disorder Systemic Lupus Erythematosus (SLE) possess autoantibodies to the human ribosomal P proteins. In order to test the cross-reactivity of the human and Plasmodium falciparum P0 proteins and to compare the SLE patients' and malaria immune persons' response, sera from 41 Indian SLE patients were tested against the P. falciparum PfP0 by Western blot analysis. Four of these samples (9.75%) were found to be cross-reactive to the carboxy-terminal domain of PfP0, but not to the amino-terminal domain of PfP0. The PfP0 reactive SLE sera inhibited the growth of Plasmodiumfalciparum in vitro. IgG purified from one such cross-reactive serum sample inhibited the growth of P. falciparum. Depletion of anti-P0 antibodies from this IgG preparation resulted in the removal of growth inhibition. Sera samples were collected from one of the PfP0 positive SLE patient from Mumbai, India, at different stages of the disease progression, and screened for the presence of anti-PfP0 antibodies. This patient's serum inhibited the parasite growth in vitro only during the phase in which anti-PfP0 antibodies were detected.

Amino Acid Sequence↗
PubMed2001

Laparoscopic management of abdominal complications in ventriculoperitoneal shunt surgery.

Ventriculoperitoneal (VP) shunts are among the most frequently performed operations in the management of hydrocephalus. Abdominal complications, though rare, are reported to occur in 5-47%. VP shunt obstruction or malfunction leads to raised intracranial pressure, which requires immediate intervention. Recently we have used the laparoscope to manage abdominal complications of VP shunt in two patients. The first patient had hydrocephalus secondary to tubercular meningitis. She developed recurrent intraabdominal cerebrospinal fluid (CSF) pseudocysts, possibly due to subtle peritoneal infection. In the second patient, who developed hydrocephalus following subarachnoid haemorrhage, the lower end of the shunt was malfunctioning due to retraction into the extraperitoneal tissues. The distal end of the VP shunt was revised in both patients with the help of a laparoscopically assisted technique. Thus, a conventional laparotomy, along with its various associated postoperative problems, was avoided without compromising the quality of surgery.

Abdomen↗
PubMed2001

Are the dominant and recessive plant disease resistance genes similar? A case study of rice R genes and Xanthomonas oryzae pv. oryzae races.

The resistance of rice to its bacterial blight pathogen Xanthomonas oryzae pv. oryzae (Xoo) has both qualitative and quantitative components that were investigated using three near-isogenic line sets for four resistance (R) genes (Xa4, xa5, xa13, and Xa21) and 12 Xoo races. Our results indicate that these two resistance components of rice plants were associated with the properties of the R genes. The qualitative component of the R genes was reflected by their large effects against corresponding avirulent Xoo races. The quantitative component of the R genes was their residual effects against corresponding virulent races and their epistatic effects, which together could lead to high-level resistance in a race-specific manner. Our results revealed important differences between the different types of R genes. Two R genes, Xa4 and Xa21, showed complete dominance against the avirulent Xoo races and had large residual effects against virulent ones. They acted independently and cumulatively, suggesting they are involved in different pathways of the rice defensive system. The third R gene, xa5, showed partial dominance or additivity to the avirulent Xoo races and had relatively small but significant residual effects against the virulent races. In contrast, xa13 was completely recessive, had no residual effects against the virulent races, and showed more pronounced race specificity. There was a strong interaction leading to increased resistance between xa13 and xa5 and between either of them and Xa4 or Xa21, suggesting their regulatory roles in the rice defensive pathway(s). Our results indicated that high-level and durable resistance to Xoo should be more efficiently achieved by pyramiding different types of R genes.

Genes, Dominant↗
PubMed2001

Comparison of results of skin prick tests, enzyme-linked immunosorbent assays and food challenges in children with respiratory allergy.

The present study was undertaken to investigate if enzyme-linked immunosorbent assays (ELISA) alone or in combination with skin tests could provide a better indicator of clinical food hypersensitivity in children with respiratory allergy. Skin prick tests (SPT) were performed on 64 children with crude antigenic food extracts. Oral food challenges were administered to children to confirm or rule out allergenicity of the food(s) incriminated, on the basis of the clinical history and/or a positive skin test. ELISA tests were then performed on the serum samples of all 64 children of study group as well as 32 children of the control group. SPT was found to be more sensitive as it detected a greater number of food challenge positive patients as compared to ELISA (92.85 vs 28.57 per cent). However, ELISA was found to have better specificity than SPT (88.04 vs 64.30 per cent). Clinically significant in our patients were 18.86 per cent of positive SPT and 4.81 per cent of positive ELISA. Our study shows that an ELISA value within the normal range is a reliable predictor of non-allergy, whereas IgE determination as a screening test for allergy is not reliable. Moreover, ELISA in itself or in combination with SPT had no advantage over SPT alone in correctly diagnosing food hypersensitivity.

Allergens↗
PubMed2001

Evidence for susceptibility to malignant hyperthermia in patients with exercise-induced rhabdomyolysis.

BACKGROUND: Malignant hyperthermia (MH), heat stroke, and exercise-induced rhabdomyolysis (ER) were suspected to be related syndromes. However, it is not known whether individuals with history of ER have an increased incidence of susceptibility to MH. To establish an association between ER and susceptibility to MH, the authors determined the MH status in patients with a history of MH-like episodes induced by physical stress. METHODS: Twelve unrelated patients with ER, 18 patients with anesthesia-induced MH, and 28 controls were investigated with the in vitro contracture test (IVCT) according to the European MH Group protocol and the ryanodine contracture test. In addition, all patients were screened for genetic mutations, and histology was performed on muscle specimens. RESULTS: Ten ER patients had positive IVCT results, one patient had a negative test result, and one patient showed equivocal responses. Samples from patients with positive IVCT results showed pronounced contractures after exposition to ryanodine, as opposed to specimens from patients with negative IVCT results, which developed contractures slowly. Three ER patients had mutations at the ryanodine receptor gene. All anesthesia-induced MH patients had positive IVCT results, two of them presented the C1840T mutation. The control patients had normal contracture test results and no typical MH mutations. Histologic examination determined no specific myopathies in any patient. CONCLUSIONS: Regarding these results, the authors recommend performing muscle biopsies for histologic examination and IVCT in patients with ER. In addition, the patient should be seen by a neurologist and screened for genetic abnormalities to shed light on the genetics of MH.

Adolescent↗
PubMed2001

Use of distally based superficial sural island artery flaps in acute open fractures of the lower leg.

The reverse sural artery flap is a fasciocutaneous flap based on the median superficial sural artery and its communication with the perforating branch of the peroneal artery situated in the region of the lateral malleolar gutter. Reverse flow is established after elevation of the flap and with division of the sural artery and the nerve proximally. The authors present resurfacing of acute open fractures of the lower third of the leg in 7 patients immediately after the acute phase of injury. Reconstruction was carried out within an average of 3 days after injury. All 7 patients sustained low-velocity injuries. Although 2 patients had partial necrosis of the distal tip of the flap, all patients had excellent recovery with minimal donor site morbidity.

Adolescent↗
PubMed2001

Complementary and alternative medicine use in children.

OBJECTIVE: Adults frequently use complementary and alternative medicines (CAM). Few studies have reported how often CAM therapies are used to treat children. The purpose of this study is to describe the use of alternative therapies by children visiting an emergency department (ED) and to identify sociodemographic factors that may influence the decision to use such therapies. DESIGN: Survey of families using a self-administered questionnaire. SETTING: An urban, tertiary care pediatric emergency department. PARTICIPANTS: Convenience sample of families presenting to the ED for acute care. MAIN OUTCOME MEASURE: Use of CAM therapies to treat children. Secondary measures include the type of therapies used, types of medical problems the therapies were used for, reasons for using such therapies, use of such therapies by the child's caretakers, and sociodemographic characteristics of the children and families. RESULTS: A review of 525 completed surveys identified 63 caretakers (12%) who acknowledged that they had used at least one form of CAM therapy to treat any of their children. Homeopathic and naturopathic remedies were the most common therapies used. Parents most often used CAM therapies to treat respiratory problems in their children and were most influenced by word-of-mouth. Children who were treated with CAM therapies were more likely to have a caretaker who used such therapies. Twelve (40%) of 30 families who reported using either an herbal or homeopathic remedy, also used a prescription or over-the-counter medication at the same time to treat their child. Thirty-nine of 55 families (70.9%) reported informing their child's physician of their use of CAM therapies. CONCLUSION: CAM therapies are frequently used to treat children. Most parents who use CAM therapies to treat their children use such therapies themselves. Large proportions of children who are taking herbal supplements are also taking prescription or over-the-counter medications concurrently.

Adolescent↗
PubMed2001

Delayed presentations of congenital diaphragmatic hernia.

The delayed presentation of a congenital diaphragmatic hernia may include symptoms of acute respiratory distress or gastrointestinal obstruction. We review the presentation and management of the different types of diaphragmatic hernias. In addition, we present a case of twins with a left-sided congenital diaphragmatic hernia through the foramen of Morgagni and an associated malrotation of the gastrointestinal tract.

Diseases in Twins↗