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1.
Hum Reprod ; 31(4): 854-65, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26851602

RESUMO

STUDY QUESTION: Does investigation of metabolic perturbations in endometrial tissue of women with dormant genital tuberculosis (GTB) during the window of implantation (WOI) assist in improving the understanding of endometrial receptivity? SUMMARY ANSWER: In dormant GTB cases significant alterations in endometrial tissue metabolites occur, largely related to energy metabolism and amino acid biosynthesis in dormant GTB cases. WHAT IS KNOWN ALREADY: As an intracellular pathogen, Mycobacterium tuberculosis strongly influences the metabolism of host cells causing metabolic dysregulation. It is also accepted that dormant GTB impairs the receptive status of the endometrium. Global metabolic profiling is useful for an understanding of disease progression and distinguishing between diseased and non-diseased groups. STUDY DESIGN, SIZE, DURATION: Endometrial tissue samples were collected from patients reporting at the tertiary infertility care center during the period September 2011-March 2013. Women having tested positive for GTB were considered as the study group (n = 24). Normal healthy women undergoing sterilization (n = 26) and unexplained infertile women with repeated IVF failure (n = 21) volunteered to participate as controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: Endometrial tissue samples were collected 6-10 days after confirmation of ovulation. PCR and BACTEC-460 culture were used for diagnosing GTB. Proton nuclear magnetic resonance (1H NMR) spectra of tissue were recorded using a 700 MHz Bruker Avance AV III spectrometer. Following phase and baseline correction of all NMR spectra by Bruker Topspin 2.1 software, spectral peak alignment of the data was performed. Multivariate analysis was applied to all spectra and individual metabolites identified and multiple correlation analysis was performed. MAIN RESULTS AND THE ROLE OF CHANCE: Leucine, isoleucine, acetate, lactate, glutamate, glutamine, methionine, lysine, creatine, glycogen, glycine, proline and choline were found to be significantly increased (P < 0.05) in endometrial tissue of women with dormant GTB compared with unexplained infertile women with repeated implantation failure. Valine, citrate, succinate and aspartate were also observed to be significantly up-regulated (P < 0.01). Furthermore, a significant decrease in glucose (P < 0.05), threonine (P < 0.05), tyrosine (P < 0.01) and phenylalanine (P < 0.0001) was observed in women with dormant GTB. Pearson's correlation analysis between the expression of various endometrial receptivity markers and metabolites showed a significant negative correlation (-0.236 to -0.545, P < 0.05). Also, the metabolites were positively correlated with endometrial receptivity markers (0.207 to 0.618, P < 0.05). LIMITATIONS, REASONS FOR CAUTION: It is often difficult to diagnose dormant GTB because it tends to exist without any clinical signs or symptoms. In addition, the diagnosis of GTB by culture remains a challenge due to low detection rates and its paucibacillary nature. Testing for prostate-specific antigen or the Y chromosome in order to account for the possible influences of recent exposure to semen on endometrial metabolism would be important. WIDER IMPLICATIONS OF THE FINDINGS: The metabolic changes associated with the dormant tubercle infection are of potential relevance to clinicians for the treatment of dormant GTB-related infertility. STUDY FUNDING/COMPETING INTERESTS: Government of India, Indian Council of Medical Research. There are no conflicts of interest.


Assuntos
Infecções Assintomáticas , Endométrio/metabolismo , Interações Hospedeiro-Patógeno , Metabolômica/métodos , Mycobacterium tuberculosis/fisiologia , Tuberculose dos Genitais Femininos/metabolismo , Adulto , Aminoácidos/biossíntese , Biomarcadores/metabolismo , Biópsia , Endométrio/microbiologia , Endométrio/patologia , Metabolismo Energético , Feminino , Humanos , Índia , Infertilidade Feminina/etiologia , Mycobacterium tuberculosis/isolamento & purificação , Ressonância Magnética Nuclear Biomolecular , Centros de Atenção Terciária , Tuberculose dos Genitais Femininos/microbiologia , Tuberculose dos Genitais Femininos/patologia , Tuberculose dos Genitais Femininos/fisiopatologia
2.
J Phys Chem B ; 110(42): 20917-21, 2006 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17048908

RESUMO

Zinc nanoparticles were grown within gel-derived silica films by applying a direct current voltage. Pattern formation of metallic Zn was studied as a function of applied voltage and metal-silica ratio. Average particle size varied from 5.2 to 20.2 nm by changing the applied voltage and silica concentration. It was found that the transition from fractal to dendritic morphology was possible due to crystalline anisotropy. From high-resolution transmission electron microscopy images and X-ray diffraction pattern a possible model is proposed to explain this observation.

3.
Indian J Pediatr ; 73(2): 157-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16514228

RESUMO

A nine-year-old Nepalese girl developed hemiconvulsion, hemiplegia, epilepsy syndrome (HHE syndrome) after an episode of right-sided focal status epilepticus following acute gastroenteritis. She had left middle cerebral artery (MCA) territory infracts due to inherited protein S deficiency.


Assuntos
Epilepsia/etiologia , Hemiplegia/etiologia , Deficiência de Proteína S/complicações , Criança , Feminino , Gastroenterite/complicações , Humanos , Infarto da Artéria Cerebral Média/etiologia , Deficiência de Proteína S/diagnóstico , Convulsões/etiologia , Síndrome
4.
J Chem Phys ; 122(21): 214703, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15974758

RESUMO

Complex electrical-conductivity experimental data sets for the interfacial amorphous phase in copper-core-copper-oxide-shell nanostructured composites have been analyzed using two Kohlrausch-related frequency response models recently developed for analysis of the dispersive electrical response of conductive materials. Such analysis has been carried out for both the precursor (herein referred to as the reference) glass as well as the glass in which the core-shell nanostructure was developed after suitable heat treatment. Complex nonlinear-least-squares data fitting at each temperature employed composite Kohlrausch models that included electrode effects. Because of the lack of sufficient high-frequency data, it was necessary to use fixed, rather than free, values of the shape parameter beta1 of the model. On the basis of topological considerations, its values were set at 13 and 23 for the reference glass and the core-shell structured glass, respectively. The activation energies of resistivity for the reference and the treated glasses were found to have values of about 2 and 0.4 eV, respectively, indicating two different mechanisms of electrical conduction. A blocking-electrode measurement on the reference glass indicated the presence of an electronic as well as an ionic component of the electrical conductivity, with the ionic part dominating at the temperatures for which the present analyses were carried out.

5.
J Nanosci Nanotechnol ; 4(7): 849-54, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15570971

RESUMO

Nanocomposites containing Fe3O4 and alpha-Fe, respectively, in a SiO2 gel were prepared by subjecting a suitably chosen gel with iron ions to a reduction treatment at 923 K, followed by wet oxidation at the same temperature for 1 hour. The particle sizes of the two phases were estimated to have values in the range of 18 to 25 nm. The dc conductivity of the composites was found to arise due to a variable range hopping mechanism with a density of states calculated as approximately 10(18) eV(-1) cc(-1). The nanoparticles of alpha-Fe are believed to contribute to the latter. The ac conductivity variation as a function of frequency and temperature could be explained because of an overlapping small polaron tunneling mechanism in the Fe3O4 nanoparticles. The density of states estimated in the latter case was approximately 10(18) eV(-1) cc(-1). From the dielectric modulus spectra of the nanocomposites, a Kohlrausch-Williams-Watts (KWW) exponent of approximately 0.30 was extracted. This indicated the presence of a wide distribution of relaxation times in the system.


Assuntos
Ferro/química , Nanotecnologia/métodos , Óxidos/química , Dióxido de Silício/química , Condutividade Elétrica , Eletricidade , Compostos Férricos/química , Óxido Ferroso-Férrico , Modelos Químicos , Modelos Estatísticos , Espectrofotometria , Eletricidade Estática , Temperatura , Difração de Raios X
6.
Phys Rev B Condens Matter ; 48(8): 5167-5171, 1993 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10009030
7.
Phys Rev B Condens Matter ; 47(24): 16242-16246, 1993 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10006047
8.
Phys Rev B Condens Matter ; 47(6): 3089-3096, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10006389
9.
Phys Rev B Condens Matter ; 45(21): 12222-12226, 1992 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10001257
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