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T Singh

Publications and source records attributed to T Singh.

At least 19 recordsLinked to original sources
PubMed2006

Interactions of the fucose-specific Pseudomonas aeruginosa lectin, PA-IIL, with mammalian glycoconjugates bearing polyvalent Lewis(a) and ABH blood group glycotopes.

Pseudomonas aeruginosa Fuc > Man specific lectin, PA-IIL, is an important microbial agglutinin that might be involved in P. aeruginosa infections in humans. In order to delineate the structures of these lectin receptors, its detailed carbohydrate recognition profile was studied both by microtiter plate biotin/avidin-mediated enzyme-lectin-glycan binding assay (ELLSA) and by inhibition of the lectin-glycan interaction. Among 40 glycans tested for binding, PA-IIL reacted well with all human blood group ABH and Le(a)/Le(b) active glycoproteins (gps), but weakly or not at all with their precursor gps and N-linked gps. Among the sugar ligands tested by the inhibition assay, the Le(a) pentasaccharide lacto-N-fucopentaose II (LNFP II, Galbeta1-3[Fucalpha1-4]GlcNAcbeta1-3Galbeta1-4Glc) was the most potent one, being 10 and 38 times more active than the Le(x) pentasaccharide (LNFP III, Galbeta1-4 [Fucalpha1-3]GlcNAcbeta1-3Galbeta1-4Glc) and sialyl Le(x) (Neu5Acalpha2-3Galbeta1-4[Fucalpha1-3] GlcNAc), respectively. It was 120 times more active than Man, while Gal and GalNAc were inactive. The decreasing order of PA-IIL affinity for the oligosaccharides tested was: Le(a) pentaose > or = sialyl Le(a) tetraose > methyl alphaFuc > Fuc and Fucalpha1-2Gal (H disaccharide)>2'-fucosyllactose (H trisaccharide), Le(x) pentaose, Le(b) hexaose (LNDFH I) and gluco-analogue of Le(y) tetraose (LDFT)>H type I determinant (LNFP I)>Le(x) trisaccharide (Galbeta1-4[Fucalpha1-3]GlcNAc) > sialyl Le(x) trisaccharide >> Man >>> Gal, GalNAc, and Glc (inactive). The results presented here, in accordance with the crystal 3D structural data, imply that the combining site of PA-IIL is a small cavity-type best fitting Fucalpha1- with a specific shallow groove subsite for the remainder part of the Le(a) saccharides, and that polyvalent glycotopes enhance the reactivity. The Fuc > Man Ralstonia solanacearum lectin RSL, which resembles PA-IIL in sugar specificity, differs from it in it's better fit to the B and A followed by H oligosaccharides vs. Fuc, whereas, the second R. solanacearum lectin RS-IIL (the structural homologue of PA-IIL) binds Man > Fuc. These results provide a valuable information on PA-IIL interactions with mammalian glycoforms and the possible spectrum of attachment sites for the homing of this aggressive bacterium onto the target molecules. Such information might be useful for the antiadhesive therapy of P. aeruginosa infections.

ABO Blood-Group System↗
PubMed2005

Isolation of pathogenic Legionella species and legionella-laden amoebae in dental unit waterlines.

Legionella released into the air during treatment are a potential source of infection. Water stagnation in dental unit waterlines (DUWLs) creates biofilms and promotes the proliferation of these micro-organisms. This study investigated the presence of amoeba infected with legionella, L. pneumophila and other pathogenic Legionella species in a dental teaching hospital. Water samples were collected in the morning and afternoon from 99 dental units and 16 taps connected to the municipal water supply. Samples were plated on selective media and tested for legionella using the direct immunofluorescent antibody technique and the latex agglutination test. Legionella were found in 33% of the DUWLs and in 47% of the mains taps supplying these units. Legionella-laden amoebae occurred in one mains tap sample and in 20% of DUWLs in a clinic of the teaching hospital. L. micdadei was the predominant species isolated from this clinic. L. pneumophila serogroups 2-14 predominated in the mains water, whereas L. pneumophila serogroup 1 was found in approximately half of the contaminated DUWLs and mains taps irrespective of the time of sampling. Pathogenic Legionella species seeded by municipal water into DUWLs is a potential source of legionella infection for both dental personnel and patients during prolonged dental treatment. This problem is compounded by the presence of legionella-laden amoebae which may contain levels of organism well within the infective dose. The interaction of legionella with amoebae is an important ecological factor that may significantly increase the risk of legionellosis, and thus should be given further consideration in the refinement of risk assessment models.

Amoeba↗
PubMed2005

Cardiovascular response in anemia.

OBJECTIVE: To study the functional consequences of nutritional anemia by evaluating the exercise performance in these children. METHODS: The study was conducted on 30 each of anemic and normal children of both sexes aged between 7 and 14 years. Relevant history was taken, and detailed examination was done. These children were classified according to severity of anemia based on hemoglobin estimation as mild (10-11.9 g/dl), moderate (7-9.9 g/dl) and normal (>12 g/dl). Children with severe anemia (Hb < 7g/dl), heart disease, non-nutritional anemia, acute febrile or respiratory illness were excluded. The subjects were tested on Mortara X Scribe colour stress treadmill using the modified Bruce protocol. Continuous computerised electrocardiographic analysis was done. The parameters studied included heart rate, systolic blood pressure, double product (DP = HRxSBP), ECG changes, metabolic equivalents (METS) and exercise duration. The end point of the test was a HR of 170/min (non-fatigue group) or inability to perform further (fatigue group). Statistical analysis was done by appropriate tests. RESULTS: Fifteen children each with mild and moderate anemia and 30 age-matched controls were enrolled in the study. There was no significant difference in the resting HR, exercise duration or DP between the cases and controls. Thirty-one children reached the target HR (non-fatigue group). The end-point HR was significantly lesser among the anemic children in the fatigue group (P 0.04). The percent gain of SBP, at peak exercise (P 0.0007) and recovery SBP as percent of resting SBP (p 0.006) were significantly more in the anemic children, more so in the mildly anemic ones. Lesser METS was achieved by anemics as compared to controls (P 0.04). ECG changes occurred significantly more often in anemic children, 53.8% of those with changes being moderately anemic, the main abnormality being ST depression. None developed arrhythmia during exercise testing. CONCLUSION: The cardiovascular response to physical exercise is compromised in children with nutritional anemia and hence these children may never attain their full potential in various school activities. Prevention of anemia should be a priority in school going children.

Adolescent↗
PubMed2005

Oral versus high dose parenteral iron supplementation in pregnancy.

OBJECTIVE: To compare the effect of daily oral iron supplementation with two injections of high dose parenteral iron. METHOD: A total of 220 pregnant women with a singleton pregnancy and hemoglobin between 8 to 11 g% at 16-24 weeks gestation were identified and randomly divided into two groups. Group A was started on daily oral iron therapy of 100 mg of elemental iron. Group B was given 250 mg of iron sorbitol intramuscularly and repeated at an interval of 4-6 weeks. Blood indices were evaluated at the beginning of study and at 36 weeks to see the effect after iron supplementation in the two groups. The data were analyzed using SPSS software, version 10.1. RESULTS: Definitive and comparable improvement in hemoglobin and all the blood indices (hematocrit, MCH, MCHC, MCV, Serum iron and TIBC) was observed. The absolute change in hemoglobin and hematocrit was 1.18+/-0.68 g% and 4.02+/-2.59% in oral group, 1.34+/-0.77 g% and 4.93+/-3.65% in parenteral group, respectively. Serum ferritin showed statistically significant absolute rise (10.43+/-7.92 microg/dl) after parenteral iron supplementation as compared to oral iron supplementation (9.76+/-4.78 microg/dl). Obstetric outcome was comparable in two groups. CONCLUSION: Two treatment regimens are biologically equivalent in terms of hematological response. Two high doses of intramuscular iron can be a good substitute to meet iron requirement in pregnancy.

Administration, Oral↗
PubMed2005

Spontaneous common bile duct rupture in pregnancy.

This report describes how a rare condition in pregnancy can present with features resembling more common diagnoses in the unwell obstetric patient. Our patient presented in late pregnancy initially with clinical features similar to mild preeclampsia, with proteinuric hypertension, epigastric pain and mildly deranged liver function tests. She went on to develop signs of acute abdomen associated with a persistent tachycardia and hypotension; there was evidence of fetal compromise. Following resuscitation, emergency caesarean section was performed and evolved into a laparotomy. The diagnosis was not clear clinically at this stage, but a retrospective amylase sample suggested acute pancreatitis. There was no clinical evidence of biliary perforation, but ongoing clinical suspicion prompted a CT of the abdomen. This proved unhelpful and our diagnostic dilemma was only resolved by endoscopic retrograde cholangiopancreatography, which demonstrated a biliary leak. A stent was placed with subsequent improvement in the patient's condition. With anaesthetists increasingly involved in the multi-disciplinary management of acutely sick obstetric patients, our case highlights the need for every practitioner involved in such cases to assess each individual fully, and be constantly aware that the diagnosis might not be obvious.

Adult↗
PubMed2005

Haematological effect of iron supplementation in breast fed term low birth weight infants.

AIMS: To determine the haematological effects of iron supplementation in predominantly breast fed term low birth weight (LBW) infants. METHODS: Seventy three healthy term LBW (<2500 g), predominantly breast fed infants aged 50-80 days were randomised into two groups to receive either iron (3 mg/kg/day) (iron supplemented (IS) group; n = 37) or placebo drops (placebo (P) group; n = 36). Haematological parameters and anthropometry were measured at baseline and repeated after four and eight weeks. RESULTS: A total of 62 subjects (32 in the IS group and 30 in the P group) came for the first follow up and 26 (13 in the IS group and 13 in the P group) reported for the second visit. There were no significant differences in serum ferritin and anthropometry. However, covariates (infant age, haemoglobin, and ferritin, and maternal haemoglobin) adjusted haemoglobin change was significantly higher in the IS group after four weeks (4.6 g/l; 95% CI 0.5 to 8.8) and eight weeks (8.6 g/l; 95% CI 1.8 to 15.4). CONCLUSIONS: Iron supplementation in a therapeutic dose in term breast fed LBW infants results in a marginal increase in haemoglobin. The functional benefit of this haemoglobin rise requires further evaluation.

Adult↗
PubMed2005

Gelatinous transformation of bone marrow: a study of 43 cases.

Gelatinous marrow transformation (GMT) is an uncommon and poorly recognized condition characterized by deposition of seromucinous gelatinous material in the bone marrow stroma. Forty-three cases of GMT were studied in a period of 4 years. There was male preponderance. Fourteen cases were in pediatric age group (less than 12 years). Majority of patients had a preceding history of anorexia, malnutrition and chronic debility. All the patients had anemia. Bone marrow biopsy revealed focal or diffuse GMT. Bone marrow aspirate showed metachromatic dense mucoid material with a few entrapped hematopoietic cells on Giemsa staining. The gelatinous material stained with alcian blue at pH 2.5.

Adolescent↗
PubMed2004

An audit on trends of vaginal delivery after one previous caesarean section.

An audit of 197 patients with one previous caesarean section was undertaken over a 1-year period to determine the rates of vaginal delivery and main indications for repeat caesarean section. Trial of labour was attempted in 51.3% of women, of whom 65.3% had had a successful vaginal delivery. Vaginal birth after caesarean, however, was successful in only 33.5% of women. This low rate of vaginal birth following a previous section was due to a large number of elective caesarean sections. Maternal request was the most common indication for repeat elective caesarean section. The answer to the rising caesarean rates seems to lie in reducing the primary caesarean section rates, rigorous auditing of the unit's caesarean rates and a change in the attitude of doctors, midwives and patients towards vaginal birth after caesarean. The last might prove to be the most difficult target to achieve.

Adult↗
PubMed2002

Sensorineural hearing loss following acute bacterial meningitis in non-neonates.

OBJECTIVE: Sensorineural hearing loss (SNHL) is an important sequelae of acute bacterial meningitis (ABM) in children. This study was undertaken to determine the incidence of SNHL following meningitis in non-neonates and its correlation with various factors. METHODS: Children between the ages of 1 month and 12 years with ABM admitted in a teaching hospital over a period of 18 months were enrolled. Detailed history was taken, clinical examination performed and cerebrospinal fluid analyzed at commencement of therapy, 48 hours later and at the end of treatment. On discharge brainstem evoked response audiometry (BERA) was recorded. Data were analyzed using appropriate statistical tests. RESULTS: Out of 32 children enrolled, 9 (28.1%) developed SNHL, bilateral in 21.9% and unilateral in 6.2%. Among hearing impaired subjects, 11.2% had mild while 44.4% each had moderate and profound hearing loss. Age, presence of vomiting, altered sensorium seizures and aminoglycoside usage were not significantly different in those with and without SNHL, but the total duration of fever was (p<0.05). There was significantly higher protein content and neutrophils in the second CSF sample of those with SNHL. CONCLUSION: There is a greater than 50% probability of the child developing SNHL if neutrophil percentage in the second CSF is 80% or more. Since the overall risk of SNHL is significant in children with meningitis, it is recommended that BERA be recorded in all, so that early intervention may be possible.

Child↗
PubMed2002

Dural sinus thrombosis presenting as unilateral lobar haematomas with mass effect: an easily misdiagnosed cause of cerebral haemorrhage.

Dural sinus thrombosis has protean clinical and radiological manifestations ranging from minimal effacement of sulci with no symptoms to severe haemorrhagic infarcts associated with focal deficits, coma and even death. An uncommon form of presentation is characterized by unilateral lobar haemorrhage associated with extensive oedema and parenchymal distortion. In an acute presentation, this might resemble haemorrhage into a tumour. In delayed presentations, the haematoma, being iso- or hypodense and showing peripheral ring-like enhancement, can mimic aggressive tumours or infective processes. As this is an uncommon condition, misdiagnosis is common with the potential for mismanagement and adverse outcomes. We present five such consecutive cases that were initially misdiagnosed as other entities. Each of these cases on closer inspection show features observed on CT and MRI that should have suggested a diagnosis of dural venous sinus thrombosis. One of these cases progressed to not only extensively involve the superficial sinuses but also the deep veins, with a significant adverse outcome. The imaging features of this interesting variant of dural sinus thrombosis are reviewed. The haemodynamic basis for haemorrhage and anatomical basis for the lateralization of the lesions are discussed.

Adult↗
PubMed2002

Development and validation of hydroxy ethyl starch kits for instant use in gastroesophageal reflux and gastric motility studies.

A reduction method based on stannous chloride is described to prepare hydroxy ethyl starch kits for gastrointestinal reflux and gastric motility studies. Following verification of the consistency of radiolabelling, in vitro experiments were carried out to validate 99mTc hydroxy ethyl starch as a liquid phase and solid phase gastric motility imaging radiotracer. Gastroesophageal reflux, liquid phase and solid phase studies were then conducted in 13 adult volunteers to examine the in vivo stability of the radiotracer. High labelling efficiency (>95% when prepared at neutral pH) was consistently achieved, which remained stable in conditions simulating gastric environment. Twelve of the 13 volunteers did not show absorption of any radioactivity from the gastro-intestinal tract. 99mTc hydroxy ethyl starch is a new agent suitable for gastroesophageal reflux and gastric motility studies. It is available in kit form and is a more 'physiological' agent than 99mTc sulphur colloid for preparing a solid radioactive meal. 99mTc hydroxy ethyl starch represents a true carbohydrate meal, and unlike 99mTc sulphur colloid, is easy to prepare and can easily be standardized to produce a standard vegetarian meal.

Adult↗
PubMed2001

Oral cysticercosis--report of six cases.

BACKGROUND: Cysticercosis cellulosae rarely involves the oral region in humans. METHODS: Six cases of oral cysticercosis were diagnosed, three each in lips and buccal mucosa. Diagnosis was made by characteristic gross and histopathologic appearances. RESULTS: Of 146 cases of cysticercosis, 6 (4.1%) were of the oral cavity. All 6 cases were initially seen with painless swellings. Clinical differential diagnosis ranged from retention cyst, lipoma, fibroma, neurofibroma, and angular stomatitis. Histopathologic examination revealed cysticercus larvae. CONCLUSIONS: The oral cavity is a rare site of involvement by cysticercosis, even in an endemic area. Histopathologic findings of the excised cyst are diagnostic of the lesion.

Adolescent↗
PubMed2001

Prevalence of behavioral problems in school going children.

The study was conducted on 957 school children using Rutter B scale which was to be completed by the class teachers in Ludhiana, India. One hundred and forty-one children (14.6%) scored more than 9 points and were included in the second part of the study. An equal number of sex matched children scoring less than 9 points served as controls. Both these groups were called for an interview with a child psychiatrist along with their parents. Only 117 and 124 children turned up and were included in the analysis. Based on the screening instrument results and parental interview, 45.6% of the children were estimated to have behavioural problems, of which 36.5% had significant problems. It was noticed that neither the screening instrument nor the interview was able to detect all the problems. Scholastic under-achievement was found to be associated with maximum problems. Scholastic under-achievement can be a useful starting point of identifying children with behavioural problems. Close cooperation between school teachers, parents, and health care providers is essential to ensure healthy development of children.

Child↗
PubMed2001

Encounters with pseudoaneurysms in orthopaedic practice.

Thirteen pseudoaneurysms are presented of which five were caused as a complication of pin/wire placement of external fixators (one conventional and four Ilizarov frames). The most common symptom was the presence of profuse persistent bleeding from either the wound or the pin/wire site. In nine patients the pseudoaneurysm was directly caused by a fracture or subsequent fracture stabilisation. Pre-operative evaluation included radiography, arteriography, Doppler and computed tomography (CT) angiography. Depending on the site and size of the pseudoaneurysm management consisted of either ligation, resection and end-to-end anastamosis/vein grafting, lateral suture, endoaneurysmorrhaphy or selective embolisation.A high index of suspicion needs to be maintained following penetrating injury in the vicinity of a major vessel, particularly in the presence of persisting symptoms. External fixators are widely used to treat complex orthopaedic problems. The procedure is technically demanding, requiring a sound knowledge of cross-sectional limb anatomy. Injudicious use may result in potentially life/limb threatening complication of pseudoaneurysm.

Adolescent↗