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V V Rao

Publications and source records attributed to V V Rao.

At least 19 recordsLinked to original sources
PubMed1996

Possible paleopathological evidence of treponematosis from a megalithic site at Agripalle, India.

An Iron Age (megalithic) skull recovered from a cist burial complex at Agripalle, Andhra Pradesh, India, exhibits extensive erosion of the calvarium, areas of sclerotic diploe, irregular osteitic and periosteitic lesions, and deep ulcerations with a granulomatous appearance of nodular foci due to bone remodeling. These lesions are found over the entire surface, but are less severe in the temporal region and in the occipital region below lambda. There is extensive ulceration and destruction of the orbital roof and the nasopalatine region. A thick bony mass representing a healed lesion is present on the nasal margin. Comparison with the pathologic skeletal series of Ortner and Putschar ([1981] Smithson. Contrib. Anthropol. 28:180-218), Steinbock ([1976] Paleopathology: Diagnosis and Interpretation, pp.86-169), and Calvin ([1964] Bones and Disease: Evidence of Disease and Abnormality in Early Man) indicates that these findings warrant a diagnosis of an advanced stage of treponematosis. The material from Agripalle, together with similar specimens recovered from the sites of Bhimbetka (Iron Age) and Inamgaon (Chalcolithic), furnish additional evidence supporting the hypothesis of the prehistoric antiquity of treponemal disease in both the New and Old Worlds.

Bone Remodeling↗
PubMed1995

Characterization of multidrug resistance P-glycoprotein transport function with an organotechnetium cation.

Multidrug resistance (MDR) in mammalian cells and tumors is associated with overexpression of an approximately 170 kDa integral membrane efflux transporter, the MDR1 P-glycoprotein. Hexakis (2-methoxyisobutyl isonitrile)technetium(I) (Tc-SESTAMIBI), a gamma-emitting lipophilic cationic metallopharmaceutical, has recently been shown to be a P-glycoprotein transport substrate. Exploiting the negligible lipid membrane adsorption properties of this organometallic substrate, we studied the transport kinetics, pharmacology, drug binding, and modulation of P-glycoprotein in cell preparations derived from a variety of species and selection strategies, including SW-1573, V79, Alex, and CHO drug-sensitive cells and in 77A, LZ-8, and Alex/A.5 MDR cells. Rapid cell accumulation (t1/2 approximately 6 min) of the agent to a steady state was observed which was inversely proportional to immunodetectable levels of P-glycoprotein. Many MDR cytotoxic agents inhibited P-glycoprotein-mediated Tc-SESTAMIBI efflux, thereby enhancing organometallic cation accumulation. Median effective concentrations (EC50; microM) were as follows: vinblastine, 13; daunomycin, 55; idarubicin, 65; actinomycin D, 235; colchicine, minimal inhibition; adriamycin, no effect. P-glycoprotein modulators generally demonstrated significantly greater potency (EC50; microM): SDZ PSC 833, 0.08; cyclosporin A, 1.3; verapamil, 4.1; quinidine, 6.4; prazosin, > 300. Modulator-induced enhancement up to 100-fold was observed with Hill coefficients approximately 1, consistent with simple Michaelis-Menten kinetics. Vanadate was an efficacious transport inhibitor, while agents usually not included in the MDR phenotype were without effect. Scatchard analysis showed quinidine to be a noncompetitive inhibitor of P-glycoprotein-mediated Tc-SESTAMIBI transport, indicating allosteric effector sites on P-glycoprotein. The lipid bilayer adsorbing agents tetraphenyl borate and phloretin induced large increases in final Tc-SESTAMIBI accumulation, showing maximal accumulations 2-fold greater than classic MDR modulators and Hill coefficients >> 2. In V79 and 77A cells, modulators of PKC activity altered Tc-SESTAMIBI accumulation, while there was no indication of modulation of P-glycoprotein-mediated Tc-SESTAMIBI transport by hypotonic buffer, extracellular ATP, Cl-, or K+ (membrane potential). While recognized and avidly transported by the P-glycoprotein at buffer concentrations as low as 7 pM, Tc-SESTAMIBI at up to 100 microM only minimally modulated the cytotoxic action of colchicine, doxorubicin, or vinblastine in MDR cells. In conclusion, transport analysis with Tc-SESTAMIBI is a sensitive assay for detecting functional expression of low levels of P-glycoprotein and for the quantitative characterization of transporter modulation and regulation. The biochemical data favor a high Km, high capacity allosterically modulated translocation mechanism for P-glycoprotein-mediated transport of this organometallic cation.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

Partial trisomy 13q identified by sequential fluorescence in situ hybridization.

We report on a 19-month-old boy with partial trisomy 13q resulting from a probable balanced translocation involving chromosomes 1 and 13. The infant presented with omphalocele, malrotation, microcephaly with overriding skull bones, micrognathia, apparently low-set ears, rocker-bottom feet, and congenital heart disease, findings suggestive of trisomy 13. Karyotypic studies from peripheral blood lymphocytes documented an unbalanced karyotype 46,XY,-1,+der(1). The mother's chromosomes were normal, and the father was not available. Conventional cytogenetic techniques were unable to identify the extra material on the terminal 1q. Using fluorescence in situ hybridization (FISH) on the GTL-banded metaphases, the extra material on 1q was identified as the terminal long arm of 13, thus resulting in partial trisomy 13 (q32-qter).

Abnormalities, Multiple↗
PubMed1995

Primary lingual tuberculosis caused by M. bovis infection.

Although tuberculosis of tongue has been previously reported, its infrequent clinical presentation and increased chance of being overlooked during routine examination of the oral cavity, make it worthy of documentation. Lingual tuberculosis is usually associated with tuberculosis of the oropharynx, lungs, lymph nodes, and miliary tuberculosis. Primary tuberculosis of the tongue is extremely rare and is seldom reported. Early diagnosis of tuberculosis elsewhere in body and its effective treatment by antituberculous drugs may be the reason for its uncommon presentation. The relationship between consumption of raw or unboiled milk and tuberculosis of the tongue is ill-understood and has evidently not been reported. We take this opportunity to present the first case of primary lingual tuberculosis caused by Mycobacterium bovis related to consumption of unboiled cow milk.

Adult↗
PubMed1995

Multidrug resistance P-glycoprotein monoclonal antibody JSB-1 crossreacts with pyruvate carboxylase.

Multidrug resistance (MDR) is associated with overexpression of a 170 KD plasma membrane P-glycoprotein (P-gp), a putative energy-dependent efflux transporter that reduces intracellular accumulation of chemotherapeutic agents. For detection of P-gp expression in normal and malignant tissues, an MDR1-specific monoclonal antibody (MAb) JSB-1 has been used extensively. In this report we show that MAb JSB-1 crossreacts with a protein of M(r) approximately 130,000 present in rat liver mitochondrial inner membrane/matrix fractions. Peptide mapping and microsequencing identify this protein as pyruvate carboxylase (PC), an abundant mitochondrial enzyme. MAb JSB-1 also crossreacts with purified PC from bovine liver. Under immunoblotting conditions, this crossreactivity is partially abolished by pre-incubation of MAb JSB-1 with a 1000-fold molar excess of MAb C494 epitope-specific peptide (PNTLEGN), indicating that the epitope of MAb JSB-1 may either overlap with or be in close proximity to that of MAb C494. Immunohistochemical cross-reactivity was also demonstrated in cryosections of human skeletal muscle, a tissue known not to express P-gp. MAb JSB-1 strongly immunostained Type 1 fibers, the subtype known to contain abundant mitochondria. Use of MAb JSB-1 for detection of MDR1 P-gp expression should be approached with caution.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

MDR1 gene-specific monoclonal antibody C494 cross-reacts with pyruvate carboxylase.

Overexpression of P-glycoprotein, the plasma membrane protein product of the MDR1 gene, is a major determinant in the development of resistance to a large number of cancer chemotherapeutic agents. A battery of antibodies, including the MDR1 gene-specific monoclonal antibody (mAb) C494, is used to evaluate human tissues in clinical multidrug resistance surveillance and modulation trials. In rat liver fractions, we report that mAb C494 strongly cross-reacted with a nonmembranous M(r) approximately 130,000 protein, comigrating with core-glycosylated human MDR1 on 7% sodium dodecyl sulfate-polyacrylamide gel electrophoresis. By immunoblotting and microsequence analysis, this protein was identified as pyruvate carboxylase (PC), an abundant mitochondrial enzyme. A search of the National Center for Biotechnology Information data base, using the epitope-specific sequence of mAb C494, revealed that PC (mouse) contains four of the five most reactive amino acids (TLEG), located near the COOH-terminal end of PC at positions 1167-1170. mAb C494 specifically reacted with PC purified from bovine liver; immunoreactivity was completely abolished by preincubating mAb C494 in the presence of excess synthetic C494 epitope-specific peptide. Furthermore, in cryosections of human skeletal muscle, a tissue known not to express P-glycoprotein, peptide-displaceable immunohistochemical staining with mAb C494 showed a distinct mitochondrial pattern specific to type 1 fibers. Variable immunostaining results were obtained with formaldehyde-fixed, paraffin-embedded muscle and isolated liver mitochondrial preparations. In summary, mAb C494 cross-reacted strongly with rat, bovine, and human PC. Caution is warranted in interpretation of immunoblots and immunohistochemical sections with this putative MDR1 gene-specific mAb.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Turpentine poisoning: a case report.

The use of turpentine oil for suicidal and homicidal purposes has become quite infrequent with the increased availability of pesticides and toxic substances. Available literature exhibits few case reports of turpentine poisoning. Such a case is reported here which presented as status epilepticus, unresponsive to the usual line of treatment. Detailed clinical examination and inquiry into the case history revealed turpentine poisoning.

Adolescent↗
PubMed1994

Solid-state 27Al and cross-polarization 13C magic-angle spinning nuclear magnetic resonance characterisation of aluminas derived from basic aluminum succinate.

Solid-state 27Al and cross-polarization (CP) 13C magic-angle spinning nuclear magnetic resonance (MAS NMR) was used to characterise aluminas obtained by calcining basic aluminium succinate at different temperatures. In basic aluminium succinate, aluminium is in the tetrahedral coordination only. However, in both X-ray amorphous and gamma-aluminas aluminium is in the tetrahedral and octahedral coordination. The intensity of the aluminium peaks is at a maximum for samples calcined at 700 degrees C. 13C CP MAS NMR indicates the bonding of Al with carbon of the carboxylate group in basic aluminium succinate. Samples calcined at 400-870 degrees C do not give 13C spectra.

Aluminum↗
PubMed1994

Expression of recombinant human multidrug resistance P-glycoprotein in insect cells confers decreased accumulation of technetium-99m-sestamibi.

UNLABELLED: The multidrug-resistant P-glycoprotein is a M(r) 170,000 plasma membrane protein encoded by the mammalian multidrug resistance gene (MDR) which appears to function as an efflux transporter of a variety of potent chemotherapeutic agents. METHODS: To directly demonstrate that 99mTc-sestamibi is recognized by the human P-glycoprotein, we overexpressed recombinant human MDR1 P-glycoprotein in host Sf9 insect cells using a baculoviral vector and correlated expression of the gene product with 99mTc-sestamibi accumulation. RESULTS: In parental Sf9 cells and in wild-type baculoviral infected (control) cells, 99mTc-sestamibi accumulation asymptotically approached a plateau of 650 fmoles (mg protein)-1 (nMo)-1 and 337 fmoles (mg protein)-1 (nMo)-1, respectively. In MDR1 baculoviral infected cells, P-glycoprotein expression was maximal at 72 hr postinfection, while 99mTc-sestamibi accumulation was reduced to 12 fmole (mg protein)-1 (nMo)-1. Verapamil (500 microM), the classical MDR modulator, produced an approximately 300% enhancement of 99mTc-sestamibi accumulation in Sf9 cells expressing MDR1 P-glycoprotein, but only a 50% enhancement in parental Sf9 cells, consistent with verapamil-induced inhibition of P-glycoprotein-mediated 99mTc-sestamibi efflux. CONCLUSIONS: These data demonstrate that the recombinant protein is transiently expressed in a functional state capable of drug transport in Sf9 cell membranes and that 99mTc-sestamibi is a transport substrate recognized by the human MDR1 P-glycoprotein. Technetium-99m-sestamibi may prove useful for functionally characterizing P-glycoprotein expression in human tumors in vivo.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

L-pipecolic acid oxidation in rat: subcellular localization and developmental study.

By using a sensitive radioactive assay method, we present here evidence that L-pipecolic acid oxidase is localized in both mitochondria and peroxisomes of rat liver. Brain white matter contained a more than 2-fold higher activity of L-pipecolic acid oxidation than the brain cortex. Suborganellar fractionation studies indicate that while the enzyme is a matrix protein in mitochondria, it is membrane-associated in peroxisomes. Both rotenone and antimycin A completely inhibited the enzyme activity in mitochondria but not in peroxisomes. The enzyme was shown to be inducible in mitochondria and peroxisomes of rat liver and brain tissues by glucagon and di-(2-ethylhexyl)phthalate, respectively. We report here for the first time the developmental aspects of L-pipecolic acid oxidation activity in rat liver and brain tissues. L-Pipecolic acid oxidase activity was detectable in whole rat embryo at 10 days of gestation, suggesting active L-pipecolic acid metabolism early during development. In both liver and brain tissues L-pipecolic acid oxidation activity was highest at 15 days of gestation and decreased with age in prenatal and postnatal conditions.

Aging↗
PubMed1993

Cystatin C (CST3), the candidate gene for hereditary cystatin C amyloid angiopathy (HCCAA), and other members of the cystatin gene family are clustered on chromosome 20p11.2.

The cystatin C gene (CST3) encodes a low-molecular-weight cysteine proteinase inhibitor belonging to family II of the cystatin superfamily and is mutated in cases of hereditary cystatin C amyloid angiopathy (HCCAA). CST3, which along with other family II cystatin genes is a member of the cystatin gene family, has been assigned to chromosome 20. To investigate the genomic organization on chromosome 20, the CST3 gene and related sequences were regionally mapped by fluorescence in situ hybridization (FISH), Southern blot, and pulsed-field gel electrophoresis (PFGE) analysis using the cDNA cystatin C probe C6a and three genomic probes, C3E1, C3E2, and C3E2-2. Probe C3E2-2, which like probe C3E2 is specific for CST3, hybridized to only one HindIII and one XbaI fragment on Southern blots and to a 300-kb BssHII PFGE fragment. FISH with probe C3E2 mapped this locus to chromosome 20p11.2, with an FL-pter value of 0.37 +/- 0.07 on the physical map. Probe C3E1 containing the most conserved cystatin gene exon (exon 1) and its flanking sequences hybridized with more fragments, e.g., to eight XbaI and nine HindIII fragments on conventional Southern blots and to eight SmaI, two BssHII (900 and 300 kb), and two NotI fragments after PFGE. FISH with C3E1 revealed only one single site at 20p11.2 with an FL-pter value of 0.37 +/- 0.04, identical to that obtained with C3E2.(ABSTRACT TRUNCATED AT 250 WORDS)

Blotting, Southern↗
PubMed1992

Gene structure of semenogelin I and II. The predominant proteins in human semen are encoded by two homologous genes on chromosome 20.

The genes for semenogelin I and II, the major protein constituents of the human seminal fluid, have been characterized by three overlapping clones in bacteriophage lambda, encompassing 31.5 kilobases (kb) of genomic DNA. The two genes are located 11.5 kb apart in the region q12-q13.1 on chromosome 20. Both genes are relatively compact, spanning only 2.7 and 3.1 kb, respectively. The transcription units are composed of three exons, of which the first encodes the signal peptide, the second encodes the secreted protein, while the third solely contains 3'-noncoding nucleotides. The nucleotide sequences exhibit a similarity of close to 90% in the exons and exceeding 80% in the introns and flanking nucleotides.

Amino Acid Sequence↗
PubMed1992

Assay for L-pipecolate oxidase activity in human liver: detection of enzyme deficiency in hyperpipecolic acidaemia.

A direct assay method is described for L-pipecolate oxidase. The assay uses NaHSO3 to trap the L-alpha-amino [3H]adipate delta-semialdehyde (AAS) formed as a direct reaction product of L-pipecolate oxidase from L-[3H]pipecolic acid. The adduct so formed was separated from the substrate on Dowex 50 (H+) column. The product was identified as [3H]AAS by amino acid analysis after breaking down the adduct by boiling under acidic conditions. The assay is simpler and more specific than fluorometric methods; it is also more sensitive, requiring at most 16 micrograms of liver peroxisome-enriched protein per assay. We have used this assay procedure to detect L-pipecolate oxidase in skin fibroblasts obtained from a control subject and from patients of hyperpipecolic acidaemia and Zellweger syndrome and found that this enzyme activity is present in the control, but absent or decreased in the patients with the peroxisomal disorders.

Humans↗
PubMed1992

The gene for bone morphogenetic protein 2A (BMP2A) is localized to human chromosome 20p12 by radioactive and nonradioactive in situ hybridization.

Bone morphogenetic protein 2A (BMP2A), a member of the decapentaplegic-Vg-related family, belongs to the transforming growth factor beta superfamily and has a striking sequence similarity to the decapentaplegic locus in Drosophila melanogaster, a major determinant of pattern specification during embryogenesis. BMP2A is thought to be involved in cartilage and bone formation during embryogenesis, but may have additional functions in morphogenesis as implied by its expression in various organs and embryonic tissues of mice. Human BMP2A, assigned to chromosome 20 by the use of human-Chinese hamster ovary cell hybrids, is considered to be a reasonable candidate gene for the autosomal dominant disease of fibrodysplasia (myositis) ossificans progressiva. We have confirmed the localization of BMP2A to chromosome 20 and regionally assigned the locus to 20p12 by radioactive and nonradioactive in situ hybridization.

Bone Morphogenetic Proteins↗
PubMed1992

Developmental changes of L-lysine-ketoglutarate reductase in rat brain and liver.

1. Developmental aspects of L-lysine-ketoglutarate reductase, the first enzyme in saccharopine pathway of L-lysine degradation in rat liver and brain tissues were studied. 2. Although the adult rat brain shows negligible activity, the enzyme activity was shown to be highly active during the early stages of development. 3. The enzyme activity gradually decreased through development in the brain, whereas it gradually increased in the liver, establishing the fact that the saccharopine pathway is the major pathway in liver. 4. Our results also show that glucagon stimulated the induction of this enzyme by 2-3-fold in both adult liver and brain tissues.

Aging↗