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B Singh

Publications and source records attributed to B Singh.

At least 37 records · Page 2Linked to original sources
PubMed2006

Toll like receptor-4 expression in lipopolysaccharide induced lung inflammation.

Bacterial lipopolysaccharides (LPS) initiate immune response through Toll-like receptor 4 (TLR4). Because many a times host is confronted with secondary bacterial challenges, it is critical to understand TLR4 expression following initial provocation. We studied TLR4 expression in rats at various times after intra-tracheal instillation of LPS. Although TLR4 mRNA was undetectable in normal lungs, it increased at 6h and 12h and declined at 36h post-LPS treatment. Western blots showed TLR4 protein at all time points. Immunohistochemistry localized TLR4 in alveolar septal cells, bronchial epithelium, macrophages and endothelium of large and peribronchial blood vessels. Dual label immunoelectron microscopy showed co-localization of TLR4 and LPS in the cytoplasm and nucleus of various lung and inflammatory cells. Nuclear localization of TLR4 was confirmed with Western blots on lung nuclear extracts. We conclude that TLR4 expression in lung is sustained up to 36 hours and that TLR4 and LPS are localized in the cytoplasm and nuclei of lung cells.

Animals↗
PubMed2005

The surgical anatomy of the parotid fascia.

UNLABELLED: Currently, there are no reports in the literature of the parotid fascia suggesting that this structure is crucial to the identification of the facial nerve trunk (FNT). Traditional surgical and anatomical descriptions of this fascia report it as a collection of connective tissue large enough to be described by the unaided eye. This study was performed to investigate the composition and limit of the fascia surrounding the parotid gland. An appreciation of these on safe and effective parotid surgery was also considered. HISTO-ANATOMICAL STUDY: Microsurgical step-by-step dissection was performed on 18 adult cadavers (n=36) to define the composition, arrangement, and attachment of the parotid fascia. Samples were subjected to the Masson Trichrome Technique (1990). CLINICAL STUDY: A total of 18 patients presented for parotidectomy. Eight patients had a pleomorphic adenoma and ten had lympho-epithelial disease of the parotid gland. Boundaries of parotid fascia were posteriorly-mastoid process, anteriorly--ramus of mandible, superiorly--cartilage of external acoustic meatus, and inferiorly-imaginary line joining tip of mastoid process to ramus of mandible. These landmarks formed a quadrangular space. HISTO-ANATOMICAL STUDY (N=36): Parotid fascia formed a fibrous meshwork over the gland. In the upper two-thirds, fascia was thick and strong; in the lower one-third, fascia was thin. Soft tissue arrangement (from superficial to deep): dermis, subcutaneous fat, superficial cervical fascia, deep cervical fascia. CLINICAL STUDY (N=18): The technique described was applied consistently in all patients. Mean time for localization of FNT was 11 min (range 7-18 min). In two patients (both with an underlying inflammatory disorder of the parotid gland), a transient facial nerve palsy developed postoperatively. In both patients, this settled within 7 weeks of operation. The true surgical potential of the parotid fascia during parotidectomy has been reported.

Adenoma, Pleomorphic↗
PubMed2005

Patterns of expression of steroidogenic enzymes during the first wave of the ovine estrous cycle as compared to the preovulatory follicle.

The expression patterns of steroidogenic enzymes in ovarian antral follicles at various stages of growth in a follicular wave have not been reported for sheep. Ovaries were collected from ewes (n=4-5 per group) when the largest follicle(s) of the first wave of the cycle, as determined by ultrasonography, reached (i) 3 mm, (ii) 4 mm, (iii) > or =5 mm in diameter or when there was a single (iv) preovulatory follicle in the last wave of the cycle, 12h after estrus detection. The expression pattern of steroidogenic enzymes was quantified using immunohistochemistry and grey-scale densitometry. The expression of CYP19 in the granulosa and 3beta-HSD and CYP17 in the theca increased (P<0.01) progressively from 3 to > or =5 mm follicles in the first wave of the cycle and was lower (P<0.01) in the preovulatory follicle compared to > or =5 mm follicles. However, the expression of 3beta-HSD in the granulosa increased (P<0.05) from 3 to > or =5 mm follicles and was maintained (P<0.05) at a high level in the preovulatory follicles. The amount of CYP19 in the granulosa of the growing follicles correlated positively (r=0.5; P<0.03) with the concurrent serum estradiol concentrations. We concluded that the expression pattern of steroidogenic enzymes in theca and granulosa of follicles growing in each wave in the ewe, paralleled with serum estradiol concentrations, with the exception that concentrations of 3beta-HSD in granulosa increased continuously from follicles 3mm in diameter to the preovulatory follicle.

3-Hydroxysteroid Dehydrogenases↗
PubMed2005

Anti-inflammatory activity of alkanoids and triterpenoids from Trichodesma amplexicaule Roth.

The phytochemical investigation of Trichodesma amplexicaule guided by bioassay, to isolation of triterpenoids and aliphatic phytoconstituents. To evaluate the anti-inflammatory activities of isolated phytoconstituents, models with carrageenan-induced acute arthritis and complete Freund's adjuvant (CFA)-induced chronic arthritis in rats were conducted. The investigated results showed that alkanoic acid significantly inhibited the carrageenan-induced acute arthritis. Moreover, alkane also supressed the development of chronic arthritis induced by CFA. It has been reported that alkane was the major phytoconstituent (1.03 +/- 0.00135%) in in vivo studies.

Alkanes↗
PubMed2005

Anatomical variations of the second thoracic ganglion.

In recent years the second thoracic ganglion has gained anatomical significance as an important conduit for sympathetic innervation of the upper extremity. Thoracoscopic excision of the second thoracic ganglion is now widely recognized as affording the most effective treatment option for palmar hyperhidrosis. This study recorded the incidence, location and associated additional neural connections of the second thoracic ganglion. Bilateral dissection of 20 adult cadavers was undertaken, and all neural connections of the second thoracic ganglion were recorded. Nineteen cadavers (95%) demonstrated additional neural connections between the first thoracic ventral ramus and second intercostal nerve. These were classified as either type A (47.5%) or type B (45%) using the intrathoracic ramus (nerve of Kuntz) between the second intercostal nerve and the ventral ramus of the first thoracic nerve as a basis on both right and left sides. The second thoracic ganglion was commonly located (92.5%) in the second intercostal space at the level of the intervertebral disc between the second and third thoracic vertebrae. Fused ganglia between the second thoracic and first thoracic (5%) and stellate (5%) ganglia were noted. These findings should assist the operating surgeon with a clear knowledge of the anatomy of the second thoracic ganglion during thoracoscopic sympathectomy with a view to improving the success rate for upper limb sympathectomy.

Adult↗
PubMed2005

Case of double superior vena cava.

A 23-year-old male patient who had no history of any previous medical illness was noted to have a widened mediastinum on chest X-ray undertaken as part of a routine medical evaluation. A computer tomographic (CT) scan confirmed the widened mediastinum to be due to a double superior vena cava (SVC). No further investigations were undertaken. The patient was noted to be well when re-assessed 3 years later.

Adult↗
PubMed2005

Chemistry and hepatoprotective activity of an active fraction from Barleria prionitis Linn. in experimental animals.

Iridoid enriched fraction IF from the ethanol-water extract of aerial parts (leaves and stems) of Barleria prionitis Linn. was evaluated for hepatoprotective activity in various acute and chronic animal test models of hepatotoxicity. It afforded significant hepatoprotection against carbon tetrachloride, galactosamine and paracetamol induced hepatotoxicity. Silymarin, was used as reference hepatoprotective. In the safety evaluation study the oral LD50 was found to be more than 3000 mg/kg, with no signs of abnormalities or any mortality observed for 15 days period under observation after single dose of drug administration whereas intraperitoneal LD50 was found to be 2530 mg/kg+/-87 mg/kg. SE (n=10) in mice. The studies revealed significant and concentration dependent hepatoprotective potential of 'IF' as it reversed the majority of the altered hepatic parameters in experimental liver damage in rodents.

Acanthaceae↗
PubMed2005

Adaptogenic activity of glyco-peptido-lipid fraction from the alcoholic extract of Trichopus zeylanicus Gaerten (part II).

Anti-stress activity was carried out on glyco-peptido-lipid (AF) fraction from the alcoholic extract of Trichopus zeylanicus Gaerten and demonstrated against a battery of tests in rats and mice. AF exhibited significant anti-stress activity in dose-related manners in all the parameters studied against different models used to induce non-specific stress viz physical and chemically. The major parameters studied were immobilization induced gastric ulceration, adjuvant-induced trauma (Stress); humoral antibody synthesis in normal and immuno-suppressed mice and delayed type of hypersensitivity (DTH) reaction, chemically stress-induced alteration in hepatic function and anti-oxidant activity. The extract of Withania somnifera root (a commercial preparation available locally, Dabur India ltd.) was used to compare the results. In the safety evaluation study the maximum tolerance dose (MTD) and oral LD50 were found to be more than 3000 mg/kg, with no signs of abnormalities or any mortality observed for 15 days period under observation after single dose of drug administration. Feeding behaviour and fecal output were normal.

Animals↗
PubMed2005

Strain-specific differences in perivascular inflammation in lungs in two murine models of allergic airway inflammation.

Histological data show perivascular recruitment of inflammatory cells in lung inflammation. However, the process of perivascular inflammation is yet-to-be characterized in any systematic manner at cell and molecular levels. Therefore, we investigated impact of genetic background on perivascular inflammation in acute or chronic airway inflammation in different strains of mice. Further, to address molecular mechanisms of perivascular inflammation, we examined immunohistochemical expression of vascular adhesion protein-1 (VAP-1) in chronic airway inflammation. Histological scoring revealed time and strain specific differences in perivascular recruitment of inflammatory cells in chronic and acute airway inflammation (P < 0.05). The data show that A/J strain is significantly more susceptible for perivascular inflammation followed by BALB/c and C57BL/6, while C3H/HeJ strain showed no perivascular accumulation of inflammatory cells. Of the two strains examined for perivascular inflammation in acute airway inflammation, BALB/c showed more accumulation of inflammatory cells compared to C57BL/c. VAP-1 expression occurred in the endothelium of pulmonary arteries but not in alveolar septa or airways in the control as well as challenged mice. In the inflamed lungs from A/J mice, the VAP-1 staining in pulmonary arteries was more intense compared to the other strains. VAP-1 staining was generally observed throughout the pulmonary arterial wall in chronic lung inflammation. These data show that periarterial inflammation is influenced by the genetic background, and may be partially regulated by VAP-1.

Acute Disease↗
PubMed2005

Antigens of goat spermatozoa that recognize homologous zona pellucida.

Goat sperm surface proteins obtained from purified plasma membrane (PPM) vesicles (purity of membrane checked by marker enzymes and transmission electron microscopy) were size fractionated on an fast protein liquid chromatography (FPLC) gel filtration column. All the seven surface proteins (129, 100, 46, 28, 27, 18 and 10 kDa) obtained were further fractionated and purified on high-efficiency gel filtration (GFC-HPLC) as well as ion exchange (DEAE-HPLC) columns. Antibodies were generated against the PPM and the protein fractions. Such resolved and purified surface antigens were tested by Dot Blot Immunoassay and homologous in vitro sperm-zona binding assays. It was revealed that the binding of goat spermatozoa to homologous zona pellucida was inhibited by antisera raised against the five lower molecular weight surface antigens. Further, the components of FPLC-AIII (46 kDa; A represents antigenic protein) and IV (28 kDa) were most promising as the antibodies against these fractions inhibited sperm binding to zona pellucida even at a dilution of 1 : 1000 as tested by the sperm-zona binding assays.

Acrosome Reaction↗
PubMed2005

Recognition and optimal management of schizophrenia and related psychoses.

Schizophrenia continues to remain one of the major unsolved conditions of our time, contributing significantly to causes of disability worldwide. Advances in neuroimaging have demonstrated that schizophrenia appears to be primarily a neurodevelopmental disorder. The dopamine theory of schizophrenia continues to hold sway but interest is growing in the role of other neurotransmitters. Genetic linkage studies continue to suggest that specific chromosomes have a role in the aetiology of the condition but the findings are, as yet, inconsistent. A new generation of drug therapies and reforms of the mental health system have meant that it is now possible to treat the majority of those with this condition in the community albeit, in some instances, against their will. The medical complications of both the disorder, the lifestyle changes resulting from the disorder and the new and older medications have come to prominence in recent years. The development of guidelines for treatment has the potential to reduce the variability in clinical practice that currently exists in the management of the condition.

Antipsychotic Agents↗
PubMed2005

Absence of spinocerebellar ataxia type 3/Machado-Joseph disease within ataxic patients in the Czech population.

Although spinocerebellar ataxia type 3 (SCA3)/Machado-Joseph disease is the most common type of SCA worldwide, we did not identify any cases of the disease amongst SCA patients in the Czech population. It has been proposed that the prevalence of large normal alleles correlates with the frequency of various types of SCA. We have therefore attempted to resolve the absence of SCA3 in our population by investigating, within 204 normal chromosomes, the frequency and nature of CAG repeats as well as two intragenic polymorphisms. We found that large normal alleles with more than 33 CAG repeats were observed at a frequency of only 0.49%. Whereas most of the expanded alleles worldwide have the CA haplotype, this was the least common (5.4%) variant observed in our study, although it was associated with a larger mean CAG repeat length (26.9). We postulate that the absence of SCA3 in the Czech population might be explained by the lack of large normal alleles and consequently a relatively small reservoir for aberrant CAG expansions at the SCA3 locus.

Alleles↗
PubMed2005

Chromosomal aberrations in squamous cell carcinomas of the upper aerodigestive tract: biologic insights and clinical opportunities.

Oncogenesis results from a progressive accumulation of genetic aberrations consequent to a complex interplay between carcinogenic factors and innate infidelity of DNA surveillance mechanisms. Although the development of genetic aberrations is random, those conferring survival advantages are selected for in a Darwinian manner, thus allowing continuous adaptation to selection pressures. Chromosomal aberrations are a prominent manifestation of genetic damage, which can be closely linked with tumor behavior and outcome as exemplified by curative treatment of chronic myelogenous leukemia resulting from targeting the BCR-ABL translocation. In the case of head and neck squamous cell carcinomas (HNSCC), chromosomal changes are detectable at all stages of tumor development, providing excellent opportunities for genomic prognostication and therapy. Several studies have shown that the overall genomic profile of HNSCC is highly consistent, but individual tumors vary significantly in their complement of genetic alterations, thereby confounding clinical correlation. The application of modern genetic and bioinformatic analytic approaches has facilitated the identification of critical genomic changes in HNSCC, many of which have been linked to clinical outcome. These genetic aberrations represent excellent targets for novel therapeutics, but require validation. The initiation of phase III trials evaluating the therapeutic utility of genetic aberrations suggests a promising future for genome-based treatment of HNSCC.

Carcinoma, Squamous Cell↗
PubMed2005

Technetium-99m ciprofloxacin imaging in the diagnosis of postsurgical bony infection and evaluation of the response to antibiotic therapy: A case report.

The use of radiolabelled antibiotics is fast emerging as a promising diagnostic test for the detection of infective lesions, because of their specific binding to the bacterial component. Ciprofloxacin is a broad-spectrum antibiotic that has been used as a radiolabelled antibiotic in both the diagnosis of infections in rabbits and in clinical trials on humans. The diagnosis of skeletal microbial infections remains a challenge, especially in orthopaedic patients with implants. We present a case report of a patient with undiagnosed and unrelenting pain in the lower third of the left leg, which had persisted for 6 months. A novel scintigraphy, which was developed in-house using a 99mTC ciprofloxacin single vial kit, was used for diagnosing the active bacterial infection. A 99mTC methylene diphosphonate bone scan was also performed to locate precisely the site of the lesion. Gradually increasing concentrations of both the radiotracers confirmed the presence of active bacterial infection in the distal third of the left tibia. Follow-up scanning after antibiotic therapy showed the disappearance of the pooling of 99mTC ciprofloxacin, indicating a good response. Therefore, 99mTC ciprofloxacin has good diagnostic and prognostic applications in deep-seated covert skeletal microbial infections. However, the persistence of a focal concentration detected by the 99mTC methylene diphosphonate scan was attributed to the inflammatory and not the infective pathology.

Adult↗