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V Deshpande

Publications and source records attributed to V Deshpande.

At least 19 recordsLinked to original sources
PubMed1999

A comparative review of the structure and biosynthesis of thyroglobulin.

Thyroglobulin, the major iodoglycoprotein of the thyroid (Mr 669 kDa) has a sedimentation coefficient of 19 S and an isoelectric point (pI) of 4.4-4.7. The protein has been isolated and purified from saline extracts of the gland of several animal species, by methods such as ammonium sulfate fractionation, DEAE-cellulose chromatography and Sepharose 4B/6B gel-filtration. DEAE-cellulose chromatography of thyroglobulin from many species, by linear gradient, yielded a complex elution pattern, while camel thyroglobulin showed only a major and minor peak. As an iodoprotein, the protein has 0.1-2.0% iodine. The amino acid and iodoamino acid composition of thyroglobulins, in general, is similar. However, a high thyroxine content (15 mol/mol protein) has been noted for buffalo species. Asparagine or aspartic acid has been reported as the major N-terminal amino acid for thyroglobulins of several animal species whereas glutamic acid is the sole N-terminal amino acid for buffalo thyroglobulin. As a glycoprotein, thyroglobulin contains 8-10% total carbohydrate with galactose, mannose, fucose, N-acetyl glucosamine and sialic acid residues. The carbohydrate in the protein is distributed as two distinct units, A and B. In addition, human thyroglobulin has carbohydrate unit C. The occurrence of sulfate and phosphate as Gal-3-SO4 and Man-6-PO4, respectively, has been reported in few species. The quaternary structure of native thyroglobulin is comprised of two equal sized subunits of 330 kDa. However, the protein appears to contain 4-8 non-identical units in few species. The synthesis of thyroid hormones occurs in the matrix of the protein and is regulated by pituitary thyrotropin. The role of tyrosine residues 5 and 130 in thyroxine synthesis has been well documented.

Animals↗
PubMed1998

Neuritic Hansen's disease: an unusual presentation and a diagnostic challenge on fine-needle aspirate.

Fine-needle aspiration cytology is now routinely used in the diagnosis of cervical lumps. We report on a case of leprous neuritis which presented as a cervical swelling. A diagnosis of leprosy was suggested on the basis of globi within histiocytes. These histiocytes differed from those classically described in leprosy. Retrospective review demonstrated the presence of occasional nerve fragments, and some of these closely resembled granulomas. The possible close resemblance of this lesion to tuberculosis and a histiocytic proliferative disorder is highlighted. Recognition of nerve fragments along with histiocytes should suggest the diagnosis.

Adult↗
PubMed1998

Fine needle aspiration (FNA) cytology of Rosai Dorfman disease.

Rosai Dorfman disease (sinus histiocytosis with massive lymphadenopathy (SHML)) is a benign self-limiting disorder that commonly involves the lymph nodes. We reviewed eight cases of this entity aiming to document the cytomorphological features. Of the eight cases, a preoperative diagnosis was suggested in seven cases. Pertinent features included: numerous large histiocytes with prominent emperipolesis (documented by a halo around the cell), fine vacuoles in the cytoplasm and lymphocytes and plasma cells in the background. In some cases the histiocytes showed atypia. In one biopsy-proven case a diagnosis of Hodgkin's was suggested, emphasizing the pitfalls associated with the FNA diagnosis of this lesion.

Adult↗
PubMed1998

Giant cell phlebitis as a cause of large intestinal stricture.

Although arteritis of the gastrointestinal tract is well known, an isolated phlebitis without associated arteritis of the colon and cecum is rare. We describe a distinct form of giant cell phlebitis in a 16-year-old girl causing ischemic stricture of the large intestine. She presented with subacute intestinal obstruction and was suspected of suffering from tuberculosis. However, histopathologic examination showed giant cell phlebitis, the arterioles and arteries being spared. Although this is an extremely rare form of nonprogressive vasculitis, it should be considered in the differential diagnosis of strictures in the large intestine, especially in the young.

Adolescent↗
PubMed1997

Unusual computed tomography appearance of Castleman disease.

A case is presented here of Castleman disease in an uncommon location. Ultrasonography demonstrated a large hypoechoic mass with multiple vascular channels. On computed tomography, the lesions with a nodular contour were located lateral to the carotid sheath on the right side, and demonstrated a variegated enhancement pattern.

Adult↗
PubMed1996

Structural environment of an essential cysteine residue of xylanase from Chainia sp. (NCL 82.5.1).

N-(2,4-Dinitroanilino)maleimide (DAM) reacts covalently with the thiol group of the xylanase from Chainia leading to complete inactivation in a manner similar to N-ethylmaleimide, but provides a reporter group at the active site of the enzyme. Increasing amounts of xylan offered enhanced protection against inactivation of the xylanase by DAM. Xylan (5 mg) showed complete protection, providing evidence for the presence of cysteine at the substrate-binding site of the enzyme. Kinetics of chemical modification of the xylanase by DAM indicated the involvement of 1 mol of cysteine residue per mol of enzyme, as reported earlier [Deshpande, Hinge and Rao (1990) Biochim. Biophys. Acta 1041, 172-177]. The second-order rate constant for the reaction of DAM with the enzyme was 3.61 x 10(3) M-1.min-1. The purified xylanase was alkylated with DAM and digested with pepsin. The peptides were separated by gel filtration. The specific modified cysteinyl peptide was further purified by reverse-phase HPLC. The active-site peptide was located visually by its predominant yellow colour and characterized by a higher A340 to A210 ratio. The modified active-site peptide has the sequence: Glu-Thr-Phe-Xaa-Asp. The sequence of the peptide was distinctly different from that of cysteinyl peptide derived from a xylanase from a thermotolerant Streptomyces species, but showed the presence of a conserved aspartic acid residue consistent with the catalytic regions of other glucanases.

Actinomycetales↗
PubMed1996

A serine alkaline protease from the fungus Conidiobolus coronatus with a distinctly different structure than the serine protease subtilisin Carlsberg.

In view of the functional similarities between subtilisin Carlsberg and the alkaline protease from Conidiobolus coronatus, the biochemical and structural properties of the two enzymes were compared. In spite of their similar biochemical properties, e.g., pH optima, heat stability, molecular mass, pI, esterase activity, and inhibition by diisopropyl fluorophosphate and phenylmethlysulfonylfluoride, the proteases were structurally dissimilar as revealed by (1) their amino acid compositions, (2) their inhibition by subtilisin inhibitor, (3) their immunological response to specific anti-Conidiobolus protease antibody, and (4) their tryptic peptide maps. Our results demonstrate that although they are functionally analogous, the Conidiobolus protease is structurally distinct from subtilisin Carlsberg. The Conidiobolus protease was also different from other bacterial and animal proteases (e.g. pronase, protease K, trypsin, and chymotrypsin) as evidenced by their lack of response to anti-Conidiobolus protease antibody in double diffusion and in neutralization assays. The Conidiobolus serine protease fails to obey the general rule that proteins with similar functions have similar primary sequences and, thus, are evolutionarily related. Our results strengthen the concept of convergent evolution for serine proteases and provide basis for research in evolutionary relationships among fungal, bacterial, and animal proteases.

Amino Acids↗
PubMed1996

Preoperative parathyroid localization with sestamibi.

PURPOSE: Results of noninvasive preoperative parathyroid localization with technetium99m-labeled sestamibi are reported in a series of 51 patients. PATIENTS AND METHODS: Forty-four patients had hyperparathyroidism surgically treated for the first time and seven patients underwent reexploration for recurrent or persistent hyperparathyroidism. Preoperative scintigraphy with sestamibi was performed in all patients before surgical exploration. Results of the radionuclide studies were compared with surgical and pathologic findings. RESULTS: Twenty-six patients had solitary adenomas. All 26 were localized preoperatively by the scans. Among 18 patients with multiglandular pathology, 69 pathological glands were found at surgery. Thirty-six of these glands, in 15 patients, were localized by the scans. Among the 7 patients evaluated after failed exploration or recurrent hyperparathyroidism, 7 pathologic glands were found, of which 6 were correctly localized by the scan. Ectopic lesions in 2 patients were correctly localized by the scan. CONCLUSIONS: The authors conclude that sestamibi parathyroid localization is an effective method for preoperative parathyroid localization, with accuracy exceeding that of other noninvasive studies.

Adenoma↗
PubMed1996

Inhalation of single vs multiple metered-dose bronchodilator actuations from reservoir devices. An in vitro study.

UNLABELLED: Differences in inhalation technique with reservoir or spacer devices may affect metered-dose inhaler (MDI) dose availability to a patient. PURPOSE: This study examined the effect of single vs multiple actuations of an MDI into reservoir devices on dose delivery of albuterol, with three clinically available reservoir brands. METHODS: An in vitro lung model simulated inspiration from the MDI reservoir system. Albuterol (Proventil; Schering) was delivered by MDI, with the Monaghan Aerochamber, the Diemolding Healthcare Division (DHD) aerosol cloud enhancer (ACE), and the Schering InspirEase, using standardized volumes and inspiratory flows of 30 L min(-1). The MDI was actuated into each brand of reservoir 1, 2, or 3 times in rapid succession, followed by a single inhalation. Aerosol dose at the reservoir mouthpiece was captured on a cotton filter, dissolved in ethanol, and measured with a spectrophotometer at 278 nm. RESULTS: For all three brands of reservoir, less accumulated dose of drug is delivered with multiple actuations than with multiple single actuations each followed by inhalation. The total dose in milligrams increased significantly with two multiple actuations compared with one actuation in the Aerochamber and ACE (p<0.01), but not in the InspirEase (p>0.05). The Aerochamber, ACE, and InspirEase delivered a mean total dose (SD) of 0.0264 mg (0.012), 0.0271 mg (0.007), and 0.0136 mg (0.006), respectively, with one actuation compared to 0.0485 mg (0.011), 0.0453 mg (0.013), and 0.0218 mg (0.009) with two multiple actuations. The increase in total dose with three multiple actuations was not significant compared to two actuations for any of the brands tested (p>0.05). Although total dose increased with multiple actuations, a decline in efficiency was seen with two and three multiple actuations, compared to single actuation. The dose delivered per actuation decreased for the Aerochamber, ACE, and InspirEase from 0.0264 mg (0.012), 0.0271 mg (0.007), and 0.0136 mg (0.006) with one actuation, to 0.0243 mg (0.006), 0.0226 mg (0.006), and 0.0109 mg (0.005), respectively, with two multiple actuations, for losses of 8.0%, 16.6%, and 19.9% in dose per actuation for each brand. A further decline in delivery per actuation to 0.0164 mg (0.001), 0.0184 mg (0.004), and 0.0097 mg (0.005) for the 3 brands, respectively, was found with 3 multiple actuations before inhalation. This was a loss of 37.9%, 32.1%, and 28.7% of the dose per single actuation in each brand. There was no significant difference between the Aerochamber and the ACE in dose availability with 1, 2, or 3 actuations, but both of these brands provided significantly more drug than the InspirEase. CONCLUSION: Maximal aerosol bronchodilator from an MDI reservoir was given by single actuations each followed by a breath. Two rapid actuations followed by a breath will give a significant accumulation of dose with some loss when compared to two single actuations each followed by inhalation. Three multiple actuations led to a loss of approximately one third of the drug dose obtainable with three single actuations each followed by inhalation, for all three brands.

Administration, Inhalation↗
PubMed1991

Immunoaffinity purification of glucose/xylose isomerase from Streptomyces.

A procedure was developed to purify glucose/xylose isomerase from cell extract of Streptomyces sp. NCIM 2730 using immunoaffinity chromatography. High-titer polyclonal antibodies were raised in rabbit using electrophoretically homogeneous glucose/xylose isomerase as an antigen. The specificity of antibodies was confirmed by double immunodiffusion, rocket electrophoresis, and Western-blot ELISA, which revealed the presence of a single immunoreactive protein with an Mr of 40,000. The antibodies recognized 2-3 antigenic determinants/mol of enzyme and were found to partially neutralize the enzymatic activity in an immunotitration experiment. The affinity gel was prepared by coupling antibodies at pH 10.0 to divinyl sulfone-activated Sepharose CL-4B. The glucose/xylose isomerase purified by immunoaffinity chromatography yielded 75% recovery with a single enzymatically active protein band on gel electrophoresis and showed specific activity of 16 U/mg. The crossreaction of the antibodies with glucose isomerase from other actinomycetes indicated that they share common epitopes.

Aldose-Ketose Isomerases↗
PubMed1991

Buffalo thyroglobulin.

1. Buffalo thyroglobulin is the major iodoprotein of buffalo thyroid with a sedimentation coefficient of 19 S and an apparent molecular mass of 685 kDa. 2. The protein is rich in iodine (1-2%) and thyroxine bound iodine (75%), unlike thyroglobulins of other mammalian species. 3. As a glycoprotein, it has the same sugar residues as noted for other thyroglobulins, and the total carbohydrate content varies from 8.41 to 9.61%. 4. Amino acid composition of buffalo thyroglobulin is similar to other species. However, the protein has 2% more proline than other mammalian thyroglobulins. 5. Glutamic acid is the sole N-terminal amino acid of buffalo thyroglobulin, in contrast to aspartic acid or asparagine for several other species. 6. The quaternary structure of the protein appears to be comprised of eight non-identical subunits.

Amino Acids↗
PubMed1990

Chemical modification of xylanases: evidence for essential tryptophan and cysteine residues at the active site.

N-Bromosuccinimide (NBS) completely inactivated xylanases from Chainia and alkalophilic and thermophilic (AT) Bacillus with a concomittant decrease in absorption at 280 nm and with second-order rate constants of 10,500 and 5000 M-1.min-1, respectively at pH 6.0 and 25 degrees C. The kinetic analysis of inactivation indicated that one and three tryptophan residues were essential for the xylanase activity from Chainia and Bacillus, respectively. The xylanases were also inhibited by 2-hydroxy-5-nitrobenzyl bromide (HNBB). The modification of cysteine residues by p-hydroxymercurybenzoate (PHMB) and N-ethylmaleimide did not cause a loss in activity of the xylanase from Bacillus, whereas that from Chainia was completely inactivated. The kinetics of inactivation revealed the involvement of one cysteine residue for xylanase from Chainia with a second-order rate constant of 50,000 M-1.min-1. The PHMB-modified enzyme failed to show the presence of titrable -SH groups. Xylan afforded complete protection against inactivation by NBS, HNBB and PHMB, indicating the involvement of tryptophan and cysteine residues at the substrate-binding region of the enzyme.

Bacillus↗
PubMed1990

N-terminal groups of buffalo thyroglobulin.

N-Terminal analysis of purified buffalo thyroglobulin by the fluorodinitrobenzene method of Sanger yielded about 1.5 moles of DNP-glutamic acid per mole of buffalo thyroglobulin. No water-soluble DNP-amino acid was detectable as N-terminal. The presence of glutamic acid has been confirmed by Edman degradation and characterization of the PTH-amino acid in different solvent systems, and also after regeneration of free amino acid from PTH-amino acid in butanol-acetic acid-water (4:1:5, v/v) system. This is in contrast to the occurrence of aspartic acid or asparagine as N-terminals for several other mammalian thyroglobulins.

Amino Acids↗
PubMed1988

Induction and catabolite repression of cellulase in Penicillium funiculosum.

The regulation of endoglucanase synthesis in Penicillium funiculosum is investigated using a method based on the viscosity lowering effect on carboxy methyl cellulose (CMC) by endoglucanase. Cellobiose (1 mg/L) causes induction, whereas glucose (5 g/L) does not repress the enzyme formation. Lactose (5 g/L) has no effect on the synthesis of cellulase. Avicel and cellulose powder (CP) are the best inducers of cellulase and xylanase activity. Both endoglucanase and xylanase activity were induced by CMC, whereas xylan induced only xylanase activity. The effect of protease on induction of cellulase activity is discussed.

Caseins↗