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S Arya

Publications and source records attributed to S Arya.

At least 19 recordsLinked to original sources
PubMed2005

Ultrasonographic changes in malignant neck nodes during radiotherapy in head and neck squamous carcinoma.

Limited information is available about the sonomorphological changes in metastatic neck nodes during radiotherapy. The aim of this study was to evaluate the pattern of sonomorphological changes in metastatic neck nodes with radiotherapy. The study population consisted of 16 consecutive patients planned for radical radiotherapy to the head and neck. All patients were subjected to four ultrasound examinations: before therapy, at 46 Gy, at the conclusion of radiation and at first follow up. A total of 59 ultrasound examinations were performed on 16 patients. The difference between the mean number of nodes detected per patient before (10.6) and after (7.8) radiation was significant (P = 0.05). Sixteen nodes were categorized as malignant at first sonography, half of which reverted back to normal by the end of radiation. Changes in the sonomorphology of malignant cervical lymph nodes occur with radiotherapy with more that half demonstrating reversion to normal pattern. Future studies correlating this with histopathology should be considered.

Aged↗
PubMed2004

High prevalence of insulin resistance in postpubertal Asian Indian children is associated with adverse truncal body fat patterning, abdominal adiposity and excess body fat.

OBJECTIVE: The objectives were to study the relationships of insulin resistance with generalized and abdominal obesity, and body fat patterning in urban postpubertal Asian Indian children. DESIGN: Cross-sectional, population-based epidemiological study. SUBJECTS: In all, 250 (155 males and 95 females) healthy urban postpubertal children. MEASUREMENTS: Anthropometric profile, percentage of body fat (%BF), fasting serum insulin, and lipoprotein profile. RESULTS: Fasting insulin correlated significantly with body mass index (BMI), %BF, waist circumference (WC), central and peripheral skinfold thicknesses and sum of four skinfold thicknesses (Sigma 4SF) in both sexes, and with systolic blood pressure and waist-to hip circumference ratio (W-HR) in males only. Consistent increase in fasting insulin was noted with increasing values of central skinfold thickness at each tertile of peripheral skinfold thickness, WC, and %BF. Central skinfold thickness correlated with fasting insulin even after adjusting for WC, W-HR, and %BF. The odds ratios (OR) (95% CI) of hyperinsulinemia (fasting insulin concentrations in the highest quartile) were 4.7 (2.4-9.4) in overweight subjects, 8 (4.1-15.5) with high %BF, 6.4 (3.2-12.9) with high WC, 3.7 (1.9-7.3) with high W-HR, 6.8 (3.3-13.9) with high triceps skinfold thickness, 8 (4.1-15.7) with high subscapular skinfold thickness, and 10.1 (5-20.5) with high Sigma 4SF. In step-wise multiple logistic regression analysis, %BF [OR (95% CI): 3.2 (1.4-7.8)] and Sigma 4SF [OR (95% CI): 4.5 (1.8-11.3)] were independent predictors of hyperinsulinemia, similar to insulin resistance assessed by HOMA (homeostatic model of assessment) in the study. CONCLUSION: A high prevalence of insulin resistance in postpubertal urban Asian Indian children was associated with excess body fat, abdominal adiposity, and excess truncal subcutaneous fat. Primary prevention strategies for coronary heart disease and diabetes mellitus in Asian Indians should focus on the abnormal body composition profile in childhood.

Abdomen↗
PubMed2000

Soft tissue sarcomas: ultrasonographic evaluation of local recurrences.

OBJECTIVE: The diagnosis of early local recurrence of soft tissue sarcomas, especially in those treated with surgery and radiotherapy, is a difficult clinical problem. Financial constraints led us to use ultrasonography instead of CT or MR imaging. The aim of this study was to evaluate the role of ultrasonography (US) in detecting local recurrence. METHODS AND RESULTS: Fifty patients with previous treatment for soft tissue sarcomas were evaluated prospectively for recurrence by US and histopathology. Seven of the 50 patients were clinically suspected to have recurrent tumour. Ultrasonography showed recurrence in 26, no recurrence in 18, benign disease in four and was indeterminate in two cases. Ultrasonography was instrumental in guiding fine needle aspiration biopsies of small local recurrences and indeterminate lesions in 17 patients. In the sonographically tumour positive patients, histopathology confirmed recurrence in 24; one case had benign disease and one patient refused surgery. Thirteen of the 18 sonographically tumour negative patients were operated upon; all were negative for tumour on histopathology. Both the indeterminate cases showed recurrence on histopathology. The benign cases were confirmed by histopathology correlation. Ultrasound guided fine needle aspiration cytology (FNAC) was positive in 14 out of 17 patients (88%). The sensitivity and specificity of US was 92.30% and 94.4% respectively. CONCLUSION: Our study concludes that US is an extremely useful and cost effective method in the detection of early local recurrences of soft tissue sarcomas and should therefore be used for initial routine follow-up and guided biopsies.

Adolescent↗
PubMed1998

A G protein gamma subunit-like domain shared between RGS11 and other RGS proteins specifies binding to Gbeta5 subunits.

Regulators of G protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs) toward the alpha subunits of heterotrimeric, signal-transducing G proteins. RGS11 contains a G protein gamma subunit-like (GGL) domain between its Dishevelled/Egl-10/Pleckstrin and RGS domains. GGL domains are also found in RGS6, RGS7, RGS9, and the Caenorhabditis elegans protein EGL-10. Coexpression of RGS11 with different Gbeta subunits reveals specific interaction between RGS11 and Gbeta5. The expression of mRNA for RGS11 and Gbeta5 in human tissues overlaps. The Gbeta5/RGS11 heterodimer acts as a GAP on Galphao, apparently selectively. RGS proteins that contain GGL domains appear to act as GAPs for Galpha proteins and form complexes with specific Gbeta subunits, adding to the combinatorial complexity of G protein-mediated signaling pathways.

Amino Acid Sequence↗
PubMed1998

Benign metastasizing chondroblastoma: a case report.

BACKGROUND: Metastasis of histologically benign chondroblastoma is a rare event. The authors report a new case, 12th in the literature, wherein multiple lung metastases appeared almost simultaneously with the primary lesion in the right talus bone. METHODS: A histologic evaluation of the primary lesion in the talus and the pulmonary metastasis was performed, and an ultrastructural study of the latter was done. Published literature on metastasizing chondroblastoma was reviewed to identify any consistency in the pattern and the outcome. RESULTS: Metastasis of chondroblastoma is uncommon but well known. Although radiologic and histologic aggressive features have been sought, they do not necessarily correlate with the outcome. CONCLUSIONS: Metastasis in chondroblastoma has been insufficiently stressed in the literature, unlike metastasis in giant cell tumors. The purpose of this case report is not only to document this uncommon event (the 12th case of lung metastasis) but also to emphasize that patients with chondroblastoma may have metastasis at presentation. Hence, all patients need to be evaluated regularly from the onset for possible lung metastasis so that deposits can be detected early for total resection.

Adult↗
PubMed1996

The effect of hematocrit on the efficiency of hemodialysis in cases of chronic renal failure.

Twenty patients of chronic renal failure were evaluated to study the effect of increase in hematocrit (Hct) on the efficiency of hemodialysis. All the patients were subjected to two hemodialysis of identical duration with an interdialytic interval of 48 hours. All were anemic with a mean hemoglobin of 6.73 gm% and a hematocrit of 22.2%. Hematocrit was raised to a mean of 32.02% following transfusion of 2 units (600-700 ml) of whole blood (p < 0.001) in the interdialytic interval. Blood clearances (Kb). Dialysate clearance (Kd), fractional decrement and Kt/V ratio of solutes (urea, creatinine and phosphates) were calculated during both the dialysis and compared with each other. Kt/V of urea decreased from 1.0589 +/- 0.24 to 0.89 +/- 0.15 (p < 0.001), and that of creatinine 1.003 +/- 0.19 to 0.832 +/- 0.009 (p < 0.001) and phosphates 0.992 +/- 0.16 to 0.826 +/- 0.006 (p < 0.001) and it showed a negative correlation with rise in hematocrit. It was significant for creatinine and phosphates and insignificant for urea, suggesting thereby that the efficiency of dialysis decreased with increase in hematocrit. This is important in view of under dialysis in patients of normal or near normal hematocrit and suggests the need for modification of dialysis prescription in such situations.

Adult↗
PubMed1994

C1q binding properties of monomer and polymer forms of mouse IgM mu-chain variants. Pro544Gly and Pro434Ala.

The effect of replacing proline with alanine at position 434 in the C mu 3 domain (P434A) and with glycine at position 544 in the C mu 4 domain (P544G) of the mu-chain of mouse IgM has been studied. The P434A substitution results in the loss of measurable complement-mediated cytolytic activity (CML) and a decrease in the association rate constant at low ionic strength (mu = 0.06), that results in a diminished Ka for C1q binding to P434A IgM bound to haptenated cells (0.4 x 10(9) M-1). Binding of C1(qr2s2) could not be detected. In contrast, replacement of proline at 544 had no measurable effect on the cytolytic or C1q/C1 binding properties of the polymeric molecule, supporting the view that the C mu 3 domain is important in C1q binding and CML. The secreted monomeric subunit of P544G was not able to mediate CML. Also, whereas hapten-bound P544G polymer bound C1q with a functional affinity of 1.5 x 10(9) M-1 at low ionic strength (mu = 0.06), similar to that observed with wild-type polymer (1.7 x 10(9) M-1) and wild-type IgG monomer (4.7 x 10(9) M-1), no C1q binding was detected with the P544G IgM monomer. This could not be attributed to differences in glycosylation. Inasmuch as the P544G mutation per se had no effect on the C1q binding properties of the polymer, we conclude that unlike IgG, aggregation does not sufficiently enhance the avidity of IgM monomer to enable it to activate complement. Augmentation of the site must occur during polymerization or when the IgM binds to Ag.

Animals↗
PubMed1994

Mapping of amino acid residues in the C mu 3 domain of mouse IgM important in macromolecular assembly and complement-dependent cytolysis.

By analyzing the effects of single site mutations of a TNP-binding mouse IgM we have identified amino acid residues clustered in two regions in the C mu 3 domain that are important in the complement-dependent cytolytic activity of polymeric IgM. Some of the mutations also impaired IgM polymerization. For one of these clusters, D432G, P434A, and P436S, which lies on the fy2 and fy3 strands and their connecting loop, polymerization was little affected and the effect on the cytolytic activity of the polymer fraction was taken to imply direct involvement of the residue in C1 binding. The other cluster, involving residues D356A K361A and D417G, is situated at the other end of the C mu 3 domain closer to the center of the Fc mu disc. The D356A K361A and D417G mutations significantly impaired polymer formation, suggesting that these residues are necessary for proper folding or packing of the C mu 3 domains and may affect cytolysis only indirectly. Some other mutations had little or no effect on polymerization or cytolytic activity (E423A, E527G), whereas some mutations impaired only IgM polymerization without affecting cytolytic activity (D344A, K361A, K443A P544G). In others the defect in polymerization was so profound that only the monomer formed (H430A/N/Q and K438G). Our results also suggest that the C1 binding site of IgM is not strictly homologous to the C1 binding site of IgG. Although mutation of E318 of IgG has been shown to reduce its cytolytic activity, mutation of the homologous residue in IgM, E423, was without effect as were mutations of other flanking-charged residues. Proline at 436 in IgM and 331 in IgG may, however, be a common element.

Amino Acid Sequence↗
PubMed1993

The Kensey catheter.

Explore the source record for details and available documents.

Angioplasty, Balloon↗
PubMed1991

Hazards of smoking.

A strong association exists between cigarette smoking and several diseases namely, cancer of the lung, bronchitis and emphysema, cancer of the larynx, oral cavity and oesophagus, gastric and duodenal ulcers, Crohn's disease, cancer of the bladder, coronary artery disease, macrocytosis, polycythaemia, leukaemia, etc. This is due to the harmful constituents of cigarette and other modalities smoking. Smokers not only harm themselves but also harm those around. Foetal malformations, abortions, stillbirths, prematurity and low birth weight are common in smoker mothers. These are the effects of passive smoking. There is no safer cigarette in the market even by lowering its harmful constituents. Mass education about the hazards of smoking with emphasis on complete stoppage of smoking is the only way to prevent its rising incidence.

Humans↗
PubMed1987

A functional, thioester-containing alpha 2-macroglobulin homologue isolated from the hemolymph of the American lobster (Homarus americanus).

An alpha 2-macroglobulin-like protease inhibitor was isolated from the cell-free hemolymph of the american lobster (Homarus americanus) by ion-exchange chromatography and gel filtration. Whereas the undissociated molecule has a molecular weight of 342,000 as determined by ultracentrifugation studies, under reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the protein has a subunit molecular weight of 180,000. On the basis of this and other evidence, we conclude that the lobster protein is a dimer consisting of two disulfide-bonded monomers. The purified protein inhibits proteolytic enzymes but protects the esterolytic activity of trypsin toward low molecular weight substrates from inactivation by soybean trypsin inhibitor. The methylamine sensitivity of this activity suggests the presence of an internal thioester bond. This was confirmed by the covalent incorporation of [14C]methylamine, by the formation of Mr 55,000 and 125,000 autolytic cleavage fragments in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and, more directly, by the amino acid sequence of a tryptic peptide containing the putative thioester region. Whereas the N-terminal amino acid sequence (22 residues) of the protein revealed an overall identity of only 18% when compared with the human protein, the sequence of the thioester-containing peptide was highly conserved, both with respect to human alpha 2-macroglobulin and to other proteins having a thioester bond. The protein showed the "slow to fast" conformational change typical in alpha 2-macroglobulins in nondenaturing gel electrophoresis after treatment with trypsin, but not after incubation with methylamine.

Amino Acid Sequence↗
PubMed1987

Neuronal and vascular disorders of the brain and spinal cord in Menkes kinky hair disease.

A 3 2/12-year-old boy had recurrent seizures, chronic respiratory infection, and delayed physical and mental development. He also had low plasma copper content typical of Menkes syndrome. Autopsy showed marked neuronal loss and gliosis in most areas of the cerebral and cerebellar cortices, midbrain, pons, and medulla. The spinal cord showed severe demyelination in both ascending (spinocerebellar) and descending (lateral corticospinal) tracts from the cervical to the sacral level. In addition to these neuronal lesions, both the meningeal and parenchymal arterial and venous branches were remarkably dilated in the brain and spinal cord. Our previous study of this case showed abnormal perivascular innervation and abnormal axonal swelling of the postganglionic adrenergic fibers elsewhere in the body. The metabolic disorder caused by copper deficiency induces severe neuronal degeneration that is apparently exaggerated by extensive and progressive vascular abnormality.

Brain↗