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1.
J Indian Assoc Pediatr Surg ; 26(3): 208-209, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34321799
2.
Andrologia ; 46(2): 191-3, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23163819

RESUMEN

Ovotesticular disorder of sexual differentiation (OTDSD) is a rare cause of disorder of sexual differentiation predominantly having 46,XX karyotype, female phenotype and ambiguous genitalia. We report a 15-year-old having male body habitus, axillary and pubic hair, well-developed penis and right-descended testis with history of penoscrotal hypospadias correction, presenting with three episodes of cyclical haematuria, who biochemically had normal serum testosterone (338 ng dl(-1) ) which increased following hCG stimulation (614 ng dl(-1) ), elevated estradiol (17.35 pg ml(-1) ) along with elevated luteinising hormone (11.3 mIU l(-1) ) and follicle-stimulating hormone (31 mIU l(-1) ). Ultrasonography followed by micturating cystourethrogram and cystoscopy confirmed the presence of prostate, uterus, cervix and vagina draining into the urogenital sinus continuing till the penile urethra and left intra-abdominal gonad. Patient underwent hysterectomy and left gonadectomy. Histopathologic study of resected gonad confirmed presence of ovotestis. Low estradiol (1.2 pg ml(-1) ) following gonadectomy confirmed the ovotestis origin of estradiol. Chromosomal analysis revealed complex karyotype predominant being 47,XYY (50%) followed by 46,XY (26%) and 45,X (24%). This is perhaps the first report of 47,XYY/46,XY/45,X causing OTDSD in a phenotypic male.


Asunto(s)
Disgenesia Gonadal Mixta/diagnóstico , Hematuria/diagnóstico , Trastornos Ovotesticulares del Desarrollo Sexual/diagnóstico , Adolescente , Gonadotropina Coriónica , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Disgenesia Gonadal Mixta/patología , Humanos , Cariotipo , Hormona Luteinizante/sangre , Masculino , Trastornos Ovotesticulares del Desarrollo Sexual/patología , Testículo/patología , Testosterona/sangre
5.
Proc Natl Acad Sci U S A ; 106(23): 9191-6, 2009 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-19458258

RESUMEN

The amyloid-beta peptide (Abeta) can generate cytotoxic oligomers, and their accumulation is thought to underlie the neuropathologic changes found in Alzheimer's disease. Known inhibitors of Abeta polymerization bind to undefined structures and can work as nonspecific aggregators, and inhibitors that target conformations that also occur in larger Abeta assemblies may even increase oligomer-derived toxicity. Here we report on an alternative approach whereby ligands are designed to bind and stabilize the 13-26 region of Abeta in an alpha-helical conformation, inspired by the postulated Abeta native structure. This is achieved with 2 different classes of compounds that also reduce Abeta toxicity to cells in culture and to hippocampal slice preparations, and that do not show any nonspecific aggregatory properties. In addition, when these inhibitors are administered to Drosophila melanogaster expressing human Abeta(1-42) in the central nervous system, a prolonged lifespan, increased locomotor activity, and reduced neurodegeneration is observed. We conclude that stabilization of the central Abeta alpha-helix counteracts polymerization into toxic assemblies and provides a strategy for development of specific inhibitors of Abeta polymerization.


Asunto(s)
Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/química , Amiloide/metabolismo , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/química , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Animales , Animales Modificados Genéticamente , Drosophila melanogaster , Humanos , Modelos Moleculares , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Estructura Secundaria de Proteína
8.
J Mater Sci Mater Med ; 22(4): 797-807, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21442191

RESUMEN

The corrosion behaviour of heat treated Ti-13Zr-13Nb (TZN) and Ti-13Zr-13Nb-0.5B (TZNB) alloys in Hank's solution has been investigated. The microstructure of the heat treated TZN alloy consisted of α, ß or martensite. Addition of boron to TZN alloy led to the formation of dispersed TiB particles and modification of microstructure. In general, the furnace cooled TZN sample showed lower corrosion potential (E(corr)) than the air cooled sample. Aging of water quenched samples decreased the E(corr) value. The passive current density of TZN samples varied within a narrow range. Presence of boron in TZN alloy decreased the corrosion potential and substantially increased the passive current density. Results showed that boron deteriorated the corrosion resistance of TZN alloy.


Asunto(s)
Líquidos Corporales/química , Boro/química , Niobio/química , Titanio/química , Circonio/química , Aleaciones , Materiales Biocompatibles/química , Corrosión , Aleaciones Dentales/química , Electroquímica/métodos , Electrólitos , Calor , Ensayo de Materiales , Microscopía Electrónica de Rastreo/métodos , Propiedades de Superficie , Temperatura , Agua/química
9.
Opt Lett ; 34(23): 3644-6, 2009 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-19953148

RESUMEN

Three-photon-induced four-photon absorption via excited-state absorption and self-defocusing nonlinear refraction are reported for the first time, to our knowledge, in ZnO quantum dots with average sizes of 2.0+/-0.1 nm with 1064 nm radiation from a Q-switched Nd:YAG laser at a peak intensity of 2.5 GW/cm(2). By employing the three-level two-step model, the experimental results can be explained quite satisfactorily.

10.
Indian J Pathol Microbiol ; 51(1): 17-21, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18417843

RESUMEN

To evaluate the role of proliferative marker, proliferating cell nuclear antigen (PCNA) and microvessel density (MVD) as prognostic markers in renal cell carcinoma (RCC) and to see their relationship with the clinical stage and nuclear grades, we studied 30 cases of RCC for nuclear grading (Fuhrman's nuclear grade), MVD (using anti CD-34 antibody), and PCNA labeling index (using anti-PCNA antibody) over a period of 2.5 years. Staging was assessed by peroperative and radiologic findings. The area of highest MVD within the tumor was selected for microvessel count (MVC) per high-power field (0.1885 mm 2 area). PCNA labeling index was determined by counting percentage of positively stained tumor cell nuclei. PCNA labeling index above 60% was taken as high PCNA index and up to 60% was considered low. There was significant positive correlation between PCNA labeling index with both nuclear grade and clinical stage using Spearman's correlation coefficient. No association was noted between MVC with PCNA, nuclear grade, and clinical stages. Evaluation of proliferative status of RCC is a useful adjunct as a prognostic parameter as it is seen to correlate well with both clinical stage and nuclear grade. In our study, MVD was not seen to correlate with either of these.


Asunto(s)
Biomarcadores de Tumor , Carcinoma de Células Renales/diagnóstico , Carcinoma de Células Renales/patología , Adulto , Anciano , Antígenos CD34/análisis , Núcleo Celular/patología , Femenino , Humanos , Riñón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neovascularización Patológica , Pronóstico , Antígeno Nuclear de Célula en Proliferación/análisis , Radiografía , Índice de Severidad de la Enfermedad , Estadística como Asunto
11.
Nat Commun ; 7: 11875, 2016 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-27312569

RESUMEN

In the traditional Bardeen-Cooper-Schrieffer theory of superconductivity, the amplitude for the propagation of a pair of electrons with momentum k and -k has a log singularity as the temperature decreases. This so-called Cooper instability arises from the presence of an electron Fermi sea. It means that an attractive interaction, no matter how weak, will eventually lead to a pairing instability. However, in the pseudogap regime of the cuprate superconductors, where parts of the Fermi surface are destroyed, this log singularity is suppressed, raising the question of how pairing occurs in the absence of a Fermi sea. Here we report Hubbard model numerical results and the analysis of angular-resolved photoemission experiments on a cuprate superconductor. In contrast to the traditional theory, we find that in the pseudogap regime the pairing instability arises from an increase in the strength of the spin-fluctuation pairing interaction as the temperature decreases rather than the Cooper log instability.

12.
Nat Commun ; 6: 6313, 2015 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-25687135

RESUMEN

A charge-density wave (CDW) state has a broken symmetry described by a complex order parameter with an amplitude and a phase. The conventional view, based on clean, weak-coupling systems, is that a finite amplitude and long-range phase coherence set in simultaneously at the CDW transition temperature T(cdw). Here we investigate, using photoemission, X-ray scattering and scanning tunnelling microscopy, the canonical CDW compound 2H-NbSe2 intercalated with Mn and Co, and show that the conventional view is untenable. We find that, either at high temperature or at large intercalation, CDW order becomes short-ranged with a well-defined amplitude, which has impacts on the electronic dispersion, giving rise to an energy gap. The phase transition at T(cdw) marks the onset of long-range order with global phase coherence, leading to sharp electronic excitations. Our observations emphasize the importance of phase fluctuations in strongly coupled CDW systems and provide insights into the significance of phase incoherence in 'pseudogap' states.

13.
Indian J Biochem Biophys ; 26(3): 140-7, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2620909

RESUMEN

Goat liver catalase (EC 1.11.1.6) has been purified to homogeneity using the techniques of ammonium sulfate fractionation, DEAE-cellulose chromatography and gel-filtration through Ultrogel AcA-34 involving two alternating steps of column chromatography. The homogeneity of the purified enzyme was tested by native and sodium dodecyl sulfate polyacrylamide gel electrophoresis, immunodiffusion and immunoelectrophoresis. The enzyme is a tetramer having a subunit molecular weight of 58,000 +/- 3000, contains six sulfhydryl groups per mole of the enzyme and shows pH optima at pH 6.8 and 7.7. The kinetic data show no cooperativity between the substrate binding sites. Tryptophan, indoleacetic acid, cysteine, formaldehyde and sodium azide inhibit the enzyme non-competitively with Ki values of 4 +/- 1, 2.5 +/- 0.8, 6 +/- 1.5, 0.48 +/- 0.15 and 0.0013 +/- 0.0003 mM, respectively. Sulfhydryl group binding agents as well as thiol reagents inhibit the enzyme activity.


Asunto(s)
Catalasa/aislamiento & purificación , Hígado/enzimología , Animales , Catalasa/metabolismo , Cromatografía , Cabras , Concentración de Iones de Hidrógeno , Cinética
14.
Indian J Biochem Biophys ; 34(4): 354-64, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9491645

RESUMEN

Carboxymethylcellulase (CMCase) was extracted and purified from an angiosperm parasite Cuscuta reflexa free from beta-glucosidase and other enzyme activities. The molecular mass and Stokes' radius of the purified enzyme are 144 kDa and 44 A, respectively. The diffusion coefficient and frictional ratio of the enzyme were 5.15 x 10(-7) cm2/sec and 1.27. The SDS-PAGE revealed homotetrameric nature of the enzyme with a subunit molecular mass of 35 +/- 1 kDa. Titration against DTNB and NBS revealed 19 sulfhydryl groups and 8 tryptophan groups, respectively, per mole of the enzyme. A sharp pH optimum at 5.0 was obtained. Cuscuta CMCase activity is unique amongst plant endoglucanases in being stimulated by Mg2+ and Mn2+ ions and by various thiols. Reaction product analysis, mode of enzyme action and substrate specificity test suggest the endo- nature of the purified CMCase. The enzyme showed K(m) value of 26 +/- 1 mg/ml for carboxymethylcellulose (sodium salt).


Asunto(s)
Celulasa , Glicósido Hidrolasas/química , Magnoliopsida/parasitología , Plantas/enzimología , Fenómenos Químicos , Química Física , Glicósido Hidrolasas/fisiología , Peso Molecular
15.
Indian J Pathol Microbiol ; 44(3): 297-300, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12024916

RESUMEN

Twenty-five cases of Ductal carcinoma in situ(DCIS), of breast with an associated invasive component were selected for this study. The aim was to identify the percentage of malignant cases having DCIS component, to analyse the distribution of DCIS according to architecture and cytonuclear grading and evaluate the correlation between grade of DCIS with that of associated invasive component. The DCIS component was classified according to traditional architectural classification and Van-Nuys cytonuclear classification. The grading of the invasive component was done according to Nottingham's modification of Bloom-Richardson system. Architecturally 72% of DCIS components were of pure form, 28% were of mixed pattern. According to cytonuclear grading 24% cases had grade-I, 28% grade-II and 48% grade-III DCIS. The invasive component showed 16% cases in grade-III. After correlating the grade of DCIS and invasive component 91% positive correlation was found in grade-III cases followed by 66.6% in grade-I and 57.1% in grade-II cases.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/patología , Femenino , Humanos , Invasividad Neoplásica/patología
16.
Aliment Pharmacol Ther ; 39(10): 1225-34, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24666381

RESUMEN

BACKGROUND: Antepartum anti-viral therapy (AVT) is often administered to prevent perinatal transmission of hepatitis B virus (HBV) infection. Little is known about the effect of AVT on post-partum flare rates and severity. AIM: To examine whether extending AVT beyond birth influences the post-partum course. METHODS: One hundred and one pregnancies in 91 women with HBV DNA levels ≥log 7 IU/mL were included. AVT (initially lamivudine, later tenofovir disoproxil fumarate) was commenced from 32 weeks gestation and stopped soon after birth and at 12 weeks post-partum. Outcomes according to post-partum treatment duration were examined: Group 1 = AVT ≤4 weeks (n = 44), Group 2 = AVT >4 weeks (n = 43), Group 3 = no AVT (n = 14). RESULTS: The majority of women were HBeAg+ (97%), median age 29 years, baseline HBV DNA log 8.0 IU/mL and follow-up 48 weeks post-partum. Post-partum treatment duration was 2 weeks for Group 1 and 12 weeks for Group 2, P < 0.01. Flare rates were not significantly different: Group 1 = 22/44 (50%), Group 2 = 17/43 (40%) and Group 3 = 4/14 (29%), P = 0.32. Onset of flare was similar at 8/10/9 weeks post-partum for Groups 1/2/3 respectively, P = 0.34. The majority of flares spontaneously resolved. HBeAg seroconversion (n = 1/5/1 in Groups 1/2/3, P = 0.27) was not associated with treatment duration or the occurrence of a post-partum flare. CONCLUSIONS: Post-partum flares are common and usually arise early after delivery. They are often mild in severity and most spontaneously resolve. Extending anti-viral therapy does not protect against post-partum flares or affect HBeAg seroconversion rates.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Adenina/administración & dosificación , Adenina/análogos & derivados , Adenina/uso terapéutico , Adulto , Antivirales/administración & dosificación , Femenino , Estudios de Seguimiento , Antígenos e de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/transmisión , Humanos , Lamivudine/administración & dosificación , Lamivudine/uso terapéutico , Masculino , Organofosfonatos/administración & dosificación , Organofosfonatos/uso terapéutico , Periodo Posparto , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/virología , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Tenofovir , Factores de Tiempo , Adulto Joven
17.
Cell Death Dis ; 4: e543, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-23492774

RESUMEN

Protein kinase CK2 (also known as Caseine Kinase II) is an ubiquitous Ser/Thr protein kinase present in both the nucleus and cytoplasm of cells, targeting several key enzymes, growth factor receptors, transcription factors and cytoskeletal proteins. It is not only a key player in regulating cellular growth and proliferation, but also behaves as a potent suppressor of apoptosis. CK2 has been frequently found to be deregulated (mostly hyperactivated) in all cancers, prostate cancer being prominent of them. In the recent past, tumor suppressor PML (promyelocytic leukemia) has been shown to be a target of phosphorylation by CK2. This phosphorylation promotes the ubiquitin-mediated proteasomal degradation of PML thereby effectively curbing its role as a tumor suppressor. Among many others, PML has also been established to mediate its tumor suppressive role by mitigating the inactivation of active AKT (pAKT) inside the nucleus by assembling a dephosphorylating platform for nuclear pAKT. One of the immediate consequences, of this inactivation is the stabilization of FOXO3a, another well-established tumor suppressor, inside the nucleus and its downstream activities. Here, we propose a novel signaling axis apexed by deregulated CK2, dismantling the association of PML and PHLPP2 (we also report PHLPP2 to be a novel interacting partner of PML inside the nucleus), ultimately leading to the inactivation and nuclear exclusion of FOXO3a, thereby downregulating p21/p27/Bim in which degradation of PML and the concomitant stabilization of pAKT plays a cardinal part.


Asunto(s)
Carcinoma/genética , Quinasa de la Caseína II/genética , Factores de Transcripción Forkhead/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Nucleares/genética , Neoplasias de la Próstata/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Carcinoma/metabolismo , Carcinoma/patología , Quinasa de la Caseína II/metabolismo , Línea Celular Tumoral , Movimiento Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/metabolismo , Humanos , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Proteína de la Leucemia Promielocítica , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/genética , Transducción de Señal , Factores de Transcripción/metabolismo , Transcripción Genética , Proteínas Supresoras de Tumor/metabolismo , Quinasas p21 Activadas/genética , Quinasas p21 Activadas/metabolismo
19.
Phys Rev Lett ; 101(13): 137002, 2008 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-18851483

RESUMEN

In the underdoped high temperature superconductors, instead of a complete Fermi surface above Tc, only disconnected Fermi arcs appear, separated by regions that still exhibit an energy gap. We show that in this pseudogap phase, the energy-momentum relation of electronic excitations near EF behaves like the dispersion of a normal metal on the Fermi arcs, but like that of a superconductor in the gapped regions. We argue that this dichotomy in the dispersion is difficult to reconcile with a competing order parameter, but is consistent with pairing without condensation.

20.
Phys Rev Lett ; 99(15): 157001, 2007 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-17995204

RESUMEN

Angle resolved photoemission on underdoped Bi2Sr2CaCu2O8 reveals that the magnitude and d-wave anisotropy of the superconducting state energy gap are independent of temperature all the way up to T{c}. This lack of T variation of the entire k-dependent gap is in marked contrast to mean field theory. At T{c} the point nodes of the d-wave gap abruptly expand into finite length "Fermi arcs." This change occurs within the width of the resistive transition, and thus the Fermi arcs are not simply thermally broadened nodes but rather a unique signature of the pseudogap phase.

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