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1.
Front Microbiol ; 14: 1223717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533825

RESUMO

Introduction: High quality corn silage depends on factors such as corn type, stage of crop development at harvest time, fermentation time, in addition to use or not of inoculants. This study aimed to investigate the impact of maturity stage, bacterial inoculation, and storage time on fermentation, aerobic stability, and nutritional characteristics of flint corn silage and their implications for corn silage management. Methods: A flint corn hybrid was harvested very early, early, and medium (at 250, 300 and 350 g dry matter (DM)/kg as fed, respectively) and ensiled in mini-silos without (control) or with Lentilactobacillus buchneri CNCM I-4323 at 1 × 105 cfu/g for 120, 240 and 360 d to investigate how these factors interact with each other. Results and discussion: There was only a small increase (7 g/kg starch; p = 0.003) in starch digestibility (starch-D) in the silages stored for 360 d when compared to that stored for 240 d, but with no difference for 120 d. Despite the reduced starch-D (526 vs. 694 g/kg starch; p < 0.001), silages produced from medium harvest had higher (p < 0.001) starch content (317 vs. 137 g/kg DM) and higher amount of digestible starch (169 vs. 98.5 g/kg DM; p < 0.001) compared to very early harvest. The 2-way interactions (inoculation × storage time and maturity × storage time) showed that inoculation of corn silage with L. buchneri increased (p < 0.001) the aerobic stability, and that more mature crop silage had higher aerobic stability (140 h; p = 0.036) than the others (118 and 48.5 h for those silages from very early and early harvest). Conclusion: The storage for a longer time (>120 d) with the goal of increasing silage digestibility did not occur. Harvesting whole-crop flint corn with 300 to 350 g/kg DM is desirable to have higher DM yield and starch accumulation. Inoculation with L. buchneri is recommended to preserve the silage against aerobic deterioration. This study has shown the importance of harvesting flint corn at the right time, and the need for inoculation with L. buchneri to ensure greater yield, starch accumulation, and silage preservation, if 120 days of storage are not exceeded.

2.
J Phys Chem A ; 121(33): 6336-6340, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28758745

RESUMO

Melding quantum and classical mechanics is an abiding quest of physical chemists who strive for heuristic insights and useful tools. We present a surprisingly simple and accurate treatment of ground-state two-electron atoms. It makes use of only the dimensional dependence of a hydrogen atom, together with the exactly known first-order perturbation value of the electron-electron interaction, both quintessentially quantum, and the D → ∞ limit, entirely classical. The result is an analytic formula for D-dimensional two-electron atoms with Z ≥ 2. For D = 3 helium, it gives accuracy better than 2 millihartrees, which is better than current density functional theory. A kindred explicit formula for correlation energy exploits interpolation between D → ∞ and D = 1 or 2; when added to the Hartree-Fock energy, it improves accuracy for D = 3 helium to better than 0.1 millihartrees.

3.
AIDS Behav ; 18(8): 1548-59, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24523006

RESUMO

We used baseline data from a study of Black MSM/MSMW in 6 US cities to examine the association of female partnership types with disease prevalence and sexual behaviors among the 555 MSMW participants. MSMW reported more than three times as many total and unprotected sex acts with each primary as they did with each non-primary female partner. We compared MSMW whose recent female partners were: (1) all primary ("PF only", n = 156), (2) both primary and non-primary ("PF & NPF", n = 186), and (3) all non-primary ("NPF only", n = 213). HIV/STI prevalence did not differ significantly across groups but sexual behaviors did. The PF only group had the fewest male partners and was the most likely to have only primary male partners; the PF & NPF group was the most likely to have transgender partners. PF & NPF men reported the most sex acts (total and unprotected) with females; NPF only men reported the fewest. Implications for HIV risk and prevention are discussed.


Assuntos
Bissexualidade , Negro ou Afro-Americano , Soropositividade para HIV/psicologia , Comportamento Sexual/psicologia , Infecções Sexualmente Transmissíveis/psicologia , Sexo sem Proteção/psicologia , Adulto , Negro ou Afro-Americano/psicologia , Bissexualidade/psicologia , Coito , Preservativos , Feminino , Soropositividade para HIV/transmissão , Humanos , Masculino , Prevalência , Assunção de Riscos , Parceiros Sexuais/psicologia , Infecções Sexualmente Transmissíveis/transmissão , Inquéritos e Questionários , Sexo sem Proteção/prevenção & controle
4.
AIDS Behav ; 18(7): 1272-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24569888

RESUMO

In HPTN 061, a study of Black men who have sex with men (MSM), we evaluated the association of healthcare-specific racial discrimination with healthcare utilization and HIV testing among 1167 HIV-negative participants. Median age was 38 years, 41 % were uninsured, and 38 % had an annual household income <$10,000. Overall, 19 % reported healthcare-specific racial discrimination directed toward family, friend, or self; 61 % saw a healthcare provider in the previous 6 months and 81 % HIV tested within the past year. Healthcare-specific racial discrimination was positively associated with seeing a provider [adjusted odds ratio (AOR) = 1.4 (1.0, 2.0)] and HIV testing [AOR = 1.6 (1.1, 2.4)] suggesting that barriers other than racial discrimination may be driving health disparities related to access to medical care and HIV testing among Black MSM. These results contrast with previous studies, possibly due to measurement or cohort differences, strategies to overcome discrimination, or because of greater exposure to healthcare.


Assuntos
Negro ou Afro-Americano , Infecções por HIV/prevenção & controle , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde , Homossexualidade Masculina , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Racismo/estatística & dados numéricos , Adolescente , Adulto , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Razão de Chances , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Racismo/psicologia , Comportamento Sexual , Percepção Social , Fatores Socioeconômicos , Inquéritos e Questionários
5.
Hum Reprod ; 28(1): 256-64, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23054067

RESUMO

STUDY QUESTION: What are the aneuploidy rates and incidence of mosaicism in good-quality human preimplantation embryos. SUMMARY ANSWER: High-level mosaicism and structural aberrations are not restricted to arrested or poorly developing embryos but are also common in good-quality IVF embryos. WHAT IS KNOWN ALREADY: Humans, compared with other mammals, have a poor fertility rate, and even IVF treatments have a relatively low success rate. It is known that human gametes and early preimplantation embryos carry chromosomal abnormalities that are thought to lower their developmental potential. STUDY DESIGN, SIZE AND DURATION: The embryos studied came from nine young (age <35 years old) IVF patients and were part of a cohort of embryos that all resulted in healthy births. These 14 embryos inseminated by ICSI and cryopreserved on Day 2 of development were thawed, cultured overnight and allowed to succumb by being left at room temperature for 24 h. Following removal of the zona pellucida, blastomeres were disaggregated and collected. PARTICIPANTS/MATERIALS, SETTING AND METHODS: There were 91 single blastomeres collected and amplified by multiple displacement amplification. Array-comparative genomic hybridization was performed on the amplified DNA. Array-data were normalized and aneuploidy was detected by the circular binary segmentation method. MAIN RESULTS AND THE ROLE OF CHANCE: The good-quality embryos exhibited high rates of aneuploidy, 10 of 14 (71.4%) of the embryos being mosaic. While none of the embryos had the same aneuploidy pattern in all cells, 4 of 14 (28.6%) were uniformly diploid. Of the 70 analysed blastomeres, 55.7% were diploid and 44.3% had chromosomal abnormalities, while 29% of the abnormal cells carried structural aberrations. WIDER IMPLICATIONS OF THE FINDINGS: Finding such a high rate of aneuploidy and mosaicism in excellent quality embryos from cycles with a high implantation rate warrants further research on the origin and significance of chromosomal abnormalities in human preimplantation embryos. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the Instituut voor de aanmoediging van innovatie door Wetenschap en Technologie in Vlaanderen (IWT-Vlaanderen). A.M. is a PhD student at the IWT-Vlaanderen. C.S. is a postdoctoral fellow at the FWO Vlaanderen. There are no competing interests.


Assuntos
Blastômeros/patologia , Instabilidade Cromossômica , Aberrações Cromossômicas/embriologia , Mosaicismo/embriologia , Adulto , Aneuploidia , Estudos de Coortes , Hibridização Genômica Comparativa , Criopreservação , Diploide , Ectogênese , Feminino , Humanos , Infertilidade Feminina/patologia , Infertilidade Feminina/terapia , Análise de Sequência com Séries de Oligonucleotídeos , Diagnóstico Pré-Implantação , Reprodutibilidade dos Testes , Injeções de Esperma Intracitoplásmicas , Zigoto
6.
Reprod Sci ; 19(12): 1302-14, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22886285

RESUMO

Mesenchymal stromal cells (MSCs) from gestational tissues represent promising cell populations with stem cell-like properties for use in regenerative medicine. Previously, we reported that MSCs in the chorionic villi of the human placenta reside in a vascular niche. However, the niche(s) in which MSCs reside in the fetal membranes, another rich source of MSCs, remains to be determined. The cell surface markers STRO-1 and 3G5 were previously employed to identify niches in a variety of tissues and here we use these markers to report the location of the MSC niche in the human decidua parietalis. The cultured decidua parietalis MSCs (DPMSCs) isolated from the choriodecidua component of the fetal membranes possessed stem cell-like properties such as adherence to plastic, colony forming ability, and multipotent differentiation potential. Fluorescence in situ hybridization analysis showed cultured DPMSCs were of maternal origin. Immunocytochemistry demonstrated that cultured DPMSCs stained positively with stem cell surface markers 3G5, CD105, CD106, STRO-1, CD146, CD49a, and α-SMA but were negative for hematopoietic markers (CD117, CD34) and vascular markers (CD34, von Willebrand factor [vWF]). Immunohistochemistry with antibodies to stem cell surface markers and the endothelial markers on term fetal membranes revealed a vascular niche for DPMSCs, which was confirmed by immunofluorescence analysis. Both STRO-1 and vWF fluorescence signals showed substantial overlap, while CD146 and vWF signals showed partial overlap. These observations were consistent with a vascular niche.


Assuntos
Vilosidades Coriônicas/irrigação sanguínea , Decídua/irrigação sanguínea , Decídua/citologia , Células-Tronco Mesenquimais/citologia , Nicho de Células-Tronco/fisiologia , Antígenos de Superfície/análise , Biomarcadores/análise , Diferenciação Celular , Células Cultivadas , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Células-Tronco Mesenquimais/química , Gravidez
7.
Hum Reprod Update ; 18(3): 234-47, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22343781

RESUMO

BACKGROUND: Since it was established in 1997, the ESHRE PGD Consortium has been collecting data from international preimplantation genetic diagnosis (PGD) centres. Ten papers have been published, including data from January 1997 to December 2007. METHODS: The data collection originally used a hard-copy format, then an excel database and finally a FileMaker Pro database. The indications are divided into five categories: PGD for chromosome abnormalities, sexing for X-linked disease, PGD for single gene defects, preimplantation genetic screening (PGS) and PGD for social sexing. The main end-points are pregnancy outcome and follow-up of deliveries. RESULTS: In data collection I, 16 centres contributed data, which increased to 57 centres by data X (average of 39 centres per data collection). These centres contributed data on over 27 000 cycles that reached oocyte retrieval. Of these cycles, 61% were for aneuploidy screening, 17% for single gene disorders, 16% for chromosomal abnormalities, 4% for sexing of X-linked disease and 2% for social sexing. Cumulatively, 5187 clinical pregnancies gave rise to 4140 deliveries and 5135 newborns (singletons: 3182, twins: 921, triplets: 37). CONCLUSIONS: In this paper, we present an overview of the first 10 years of PGD data, highlighting trends. These include the introduction of laser-assisted biopsy, an increase in polar body and trophectoderm biopsy, new strategies, methodologies and technologies for diagnosis, including recently arrays, and the more frequent use of freezing biopsied embryos. The Consortium data reports represent a valuable resource for information about the practice of PGD.


Assuntos
Aberrações Cromossômicas , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Diagnóstico Pré-Implantação/métodos , Aneuploidia , Coleta de Dados , Bases de Dados Factuais , Feminino , Genes Ligados ao Cromossomo X , Testes Genéticos , Humanos , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Implantação/estatística & dados numéricos
8.
J Phys Chem A ; 115(43): 11921-43, 2011 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-21913705

RESUMO

We review recent research on the acetylene S(1) state that illustrates how mechanistic rather than phenomenological information about intersystem crossing (ISC) may be obtained directly from frequency-domain spectra. The focus is on the dynamically rich "doorway-mediated" ISC domain that lies between isolated spectroscopic spin-orbit perturbations and statistical-limit interactions between one singlet "bright state" and a quasi-continuum of triplet "dark states". New and improved experimental and data processing techniques permit the statistical-model curtain to be drawn back to reveal mechanistically explicit pathways via one or more identifiable, hence, manipulatable, doorway states, between a user-selected bright state and the undifferentiated bath of dark states.

9.
Bratisl Lek Listy ; 112(3): 140-2, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21452766

RESUMO

OBJECTIVES: The aim of our study was to analyse analgesic risk perception and then to compare analgesic drug choice among general practitioners. METHOD: The structured questionnaire was used and completed during continuous medical education lectures. Series of targeted open or close questions and visual analog scale (VAS) to determine drug risk perception were used. Slovak general practitioners attending continuous medical education lectures during 2004-2005 were invited to participate in the study. Group 1 consisted of respodents from Bratislava (capital city of Slovakia, n = 245) and group 2 consisted of general practitioners from 3 other cities (middle and eastern Slovakia, n = 325). Data were compared to reported adverse drug reactions. RESULTS: Quarter of doctors 25.3% (n = 62), (25.2% (n = 82) respectively), considered non-steroidal anti-inflammatory drugs to be the safest group of analgesics. Gastrointestinal damage in general was perceived as most common adverse drug reaction. 72.41% (75.94% respectively) of respondents considered analgesics as exactly or probably danger. Perceived drug risk labeled on VAS was 4.23 (SD 1.52), (3.22 (SD 2.19) respectively) (p < 0.05). Total number of reported adverse drug reactions in years 1998-2002 was 3249, 412 were related to analgesic use. Specific organotoxic adverse drug reactions (nephrotoxicity, etc.) were reported rarely. CONCLUSION: The actual perception of analgesic risk in Slovakia seems to be generally inadequate. We found only a low support of spontaneous adverse drug reactions reporting to the national monitoring system (Tab. 1, Fig. 2, Ref. 11).


Assuntos
Analgésicos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Atitude do Pessoal de Saúde , Clínicos Gerais/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Inquéritos e Questionários
10.
Hum Reprod ; 26(1): 14-24, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20966460

RESUMO

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) PGD Consortium published a set of Guidelines for Best Practice PGD to give information, support and guidance to potential, existing and fledgling PGD programmes. Subsequent years have seen the introduction of new technologies as well as the evolution of current techniques. Additionally, in light of recent advice from ESHRE on how practice guidelines should be written/formulated, the Consortium believed it was timely to update the PGD guidelines. Rather than one document that covers all of PGD, the new guidelines are separated into four documents, including one relating to organization of the PGD centre and three relating to the methods used: DNA amplification, fluorescence in situ hybridization and biopsy/embryology. Here, we have updated the sections on organization of the PGD centre. One area that has continued to expand is Transport PGD, in which patients are treated at one IVF centre, whereas their gametes/embryos are tested elsewhere, at an independent PGD centre. Transport PGD/preimplantation genetic screening (PGS) has a unique set of challenges with respect to the nature of the sample and the rapid turn-around time required. PGS is currently controversial. Opinions of laboratory specialists and clinicians interested in PGD and PGS have been taken into account here. Current evidence suggests that PGS at cleavage stages is ineffective, but whether PGS at the blastocyst stage or on polar bodies might show improved delivery rates is still unclear. Thus, in this revision, PGS has been included. This document should assist everyone interested in PGD/PGS in developing the best laboratory and clinical practice possible.


Assuntos
Administração de Instituições de Saúde/métodos , Diagnóstico Pré-Implantação , Acreditação/organização & administração , Aconselhamento Genético/organização & administração , Humanos , Gestão de Recursos Humanos/métodos , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Encaminhamento e Consulta/organização & administração , Manejo de Espécimes/normas
11.
Hum Reprod ; 26(1): 25-32, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20966461

RESUMO

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) PGD Consortium published a set of Guidelines for Best Practice PGD to give information, support and guidance to potential, existing and fledgling PGD programmes. The subsequent years have seen the introduction of new technologies as well as evolution of current techniques. Additionally, in light of recent advice from ESHRE on how practice guidelines should be written and formulated, the Consortium believed it was timely to revise and update the PGD guidelines. Rather than one document that covers all of PGD, the new guidelines are separated into four new documents that apply to different aspects of a PGD programme, i.e. organization of a PGD centre, fluorescence in situ hybridization (FISH)-based testing, amplification-based testing and polar body and embryo biopsy for PGD/preimplantation genetic screening (PGS). Here, we have updated the sections that pertain to FISH-based PGD. PGS has become a highly controversial technique. Opinions of laboratory specialists and clinicians interested in PGD and PGS have been taken into account here. Whereas some believe that PGS does not have a place in clinical medicine, others disagree; therefore, PGS has been included. This document should assist everyone interested in PGD/PGS in developing the best laboratory and clinical practice possible. Topics covered in this guideline include inclusion/exclusion criteria for FISH-based PGD testing, referrals and genetic counselling, preclinical validation of tests, FISH-based testing methods, spreading of cells for analysis, set-up of local IVF centre and transport PGD centres, quality control/ quality assurance and diagnostic confirmation of untransferred embryos.


Assuntos
Transtornos Cromossômicos/diagnóstico , Hibridização in Situ Fluorescente/métodos , Diagnóstico Pré-Implantação/métodos , Blastocisto , Aberrações Cromossômicas , Humanos , Controle de Qualidade , Análise para Determinação do Sexo , Manejo de Espécimes/normas
12.
Hum Reprod ; 24(5): 1221-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19155287

RESUMO

The European Society of Human Reproduction and Embryology PGD Consortium has collected data on PGD cycles and deliveries since 1997. From 15,158 cycles, 24 misdiagnoses and adverse outcomes have been reported; 12/2538 cycles after polymerase chain reaction and 12/12,620 cycles after fluorescence in situ hybridization. The causes of misdiagnosis include confusion of embryo and cell number, transfer of the wrong embryo, maternal or paternal contamination, allele dropout, use of incorrect and inappropriate probes or primers, probe or primer failure and chromosomal mosaicism. Unprotected sex has been mentioned as a cause of adverse outcome not related to technical and human errors. The majority of these causes can be prevented by using robust diagnostic methods within laboratories working to appropriate quality standards. However, diagnosis from a single cell remains a technically challenging procedure, and the risk of misdiagnosis cannot be eliminated.


Assuntos
Erros de Diagnóstico/normas , Diagnóstico Pré-Implantação/normas , Erros de Diagnóstico/prevenção & controle , Feminino , Humanos , Hibridização in Situ Fluorescente/normas , Mosaicismo , Reação em Cadeia da Polimerase/normas , Gravidez , Controle de Qualidade , Sociedades Médicas
13.
Hum Reprod ; 23(4): 741-55, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18238908

RESUMO

The seventh report of the ESHRE PGD Consortium is presented documenting cycles collected for the calendar year 2004 and follow-up of the pregnancies and babies born subsequent to these cycles up to October 2005. Since the beginning of the data collections, there has been a steady increase in the number of cycles, pregnancies and babies reported. For data collection VII, 45 centres have participated, reporting on 3358 cycles to oocyte retrieval (OR), 679 pregnancies and 528 babies born. Five hundred and fifty nine OR were reported for chromosomal abnormalities, 113 OR for sexing for X-linked diseases, 520 OR for monogenic diseases, 2087 OR for PGS, and 79 OR for social sexing. Data VII is compared with the cumulative data for data collections I-VI.


Assuntos
Aberrações Cromossômicas , Doenças Genéticas Inatas/diagnóstico , Taxa de Gravidez , Diagnóstico Pré-Implantação , Aborto Espontâneo/diagnóstico , Coleta de Dados , Feminino , Seguimentos , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Humanos , Masculino , Recuperação de Oócitos , Gravidez , Resultado da Gravidez , Pré-Seleção do Sexo
14.
Brain Res ; 1190: 1-14, 2008 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18093574

RESUMO

We have investigated using single channel patch-clamp methods potassium channel prevalence in hippocampal neurones from two animal models of AD. Experiments have been carried out on transgenic mice (Tg2576) carrying the Swedish mutation (K670N/M671L) and rats receiving ventricular infusions of okadaic acid. In cell-attached patches from hippocampal neurones from the Tg2576 and control littermate mice there were three principal unitary conductance - 22 pS, 111 pS and 178 pS. The two channels of intermediate and large conductance were voltage-dependent, highly active in cell-attached patches, activity decreasing markedly on hyperpolarisation. The large conductance channel was sensitive to TEA, iberiotoxin, was activated in excised inside-out patches by Ca 2+(i) and is the type I maxi-K+ channel. Significantly, there was a reduction in the prevalence of a TEA-sensitive 113 pS channel in neurones from TG2576 mice with a corresponding increase in prevalence of the maxi-K+ channel. There was no difference in the characteristics of maxi-K+ between patches in neurones from the transgenic and littermate controls. In the rat model single channel analysis was performed on hippocampal neurons from three groups of animals i.e. non-operated, and these receiving an infusion of vehicle or vehicle with okadaic acid. Three principal unitary conductances of around 18 pS, 118 pS and 185 pS were also observed in cell-attached recordings from these three groups. The intermediate and high conductance channels were blocked by TEA or 4-AP or 140 mM RbCl. There were no statistically significant differences in the channel prevalence or channel density between the control and test groups.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Canais de Potássio/metabolismo , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Inibidores Enzimáticos , Hipocampo/citologia , Masculino , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Ácido Okadáico , Técnicas de Patch-Clamp , Canais de Potássio/classificação , Ratos , Ratos Endogâmicos , Ratos Sprague-Dawley
15.
J Phys Chem A ; 111(49): 12534-7, 2007 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-17918920

RESUMO

Surface electron ejection by laser-excited metastables (SEELEM) and LIF spectra of acetylene were simultaneously recorded in the regions of the A1Au-X1Sigmag+ nominal 2(1)3(1)4(2) Ka=1<--00 and 2(1)3(1)6(2) Ka=1<--00 bands near 46,140 cm(-1). The upper states of these two bands are separated by only approximately 100 cm(-1), and the two S1 vibrational levels are known to be strongly mixed by anharmonic and Coriolis interactions. Strikingly different patterns were observed in the SEELEM spectra in the regions of the 2(1)3(1)4(2) and 2(1)3(1)6(2) vibrational levels. Because the equilibrium structure of the T3 electronic state is known to be nonplanar, excitation of nu4 (torsion) and nu6 (antisymmetric in-plane bend) are expected respectively to promote and suppress vibrational overlap between low-lying S1 and T3 vibrational levels. The nearly 50:50 mixed 2(1)3(1)4(2)-2(1)3(1)6(2) character of the S1 vibrational levels rules out this simple Franck-Condon explanation for the different appearance of the SEELEM spectra. A simple model is applied to the SEELEM/LIF spectra to explain the differences between spectral patterns in terms of a T3 doorway-mediated singlet-triplet coupling model.

16.
J Chem Phys ; 127(12): 124302, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17902898

RESUMO

High resolution optical spectroscopy has been used to study a molecular beam of molybdenum monocarbide (MoC). The Stark effect of the R(e)(0) and Q(fe)(1) branch features of the [18.6] (3)Pi(1)-X (3)Sigma(-)(0,0) band system of (98)MoC were analyzed to determine the permanent electric dipole moments mu(e) of 2.68(2) and 6.07(18) D for the [18.6] (3)Pi(1)(nu=0) and X (3)Sigma(-)(nu=0) states, respectively. The dipole moments are compared with the experimental value for ruthenium monocarbide [T. C. Steimle et al., J. Chem. Phys. 118, 2620 (2003)] and with theoretical predictions. A molecular orbital correlation diagram is used to interpret the observed and predicted trends of ground state mu(e) values for the 4d-metal monocarbides series.

17.
Acta Diabetol ; 44(4): 233-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17874223

RESUMO

Nateglinide (Starlix((R))) is licensed for the treatment of Type 2 diabetes in patients inadequately controlled with metformin. The study objective was to monitor the safety and use of nateglinide prescribed by primary care physicians (GPs) in England, using the observational cohort technique, Prescription-Event Monitoring. Exposure data were derived from dispensed nateglinide prescriptions issued October 2001-June 2004; demographic and outcome data, from questionnaires sent to patients' GPs at least 6 months after patients' first prescription. Incidence densities (IDs; number of first reports of an event/1,000 patient-months exposure) were calculated for month 1 (ID(1)), months 2-6 (ID(2-6)); rate differences [ID(1)-ID(2-6) (+99% CI)] were examined. Cohort comprised 4,557 patients, median age 60 (IQR 51, 68 years); 2,439 (53.5%) male; 3,463 (76.0%) received nateglinide in combination with metformin. GPs reported 1,625 reasons for stopping in 1,474 (32.3%) patients and 80 events as adverse drug reactions in 66 (1.5%) patients. Events associated with starting treatment included nausea/vomiting [ID(1)-ID(2-6) 9.6 (99% CI 5.3, 13.9)], malaise/lassitude [ID(1)-ID(2-6) 6.03 (99% CI 2.2, 9.9)]. No serious hypersensitivity reactions were reported. Two pregnancies (< 0.1%) and 73 deaths (1.6%) were reported. Nateglinide appeared to be generally well tolerated when used in combination with metformin for the treatment of Type 2 diabetes.


Assuntos
Cicloexanos/normas , Cicloexanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicina de Família e Comunidade , Hipoglicemiantes/normas , Hipoglicemiantes/uso terapêutico , Fenilalanina/análogos & derivados , Idoso , Confidencialidade , Cicloexanos/efeitos adversos , Monitoramento de Medicamentos/métodos , Monitoramento de Medicamentos/normas , Prescrições de Medicamentos , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nateglinida , Fenilalanina/efeitos adversos , Fenilalanina/normas , Fenilalanina/uso terapêutico , Segurança
18.
Hum Reprod ; 22(2): 323-36, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17132677

RESUMO

The sixth report of the ESHRE PGD Consortium is presented, relating to cycles collected for the calendar year 2003 and follow-up of the pregnancies and babies born up to October 2004. Since the beginning of the data collections, there has been a steady rise in the number of cycles, pregnancies and babies reported. For this report, 50 centres participated, reporting on 2984 cycles, 501 pregnancies and 373 babies born. Five hundred and twenty-nine cycles were reported for chromosomal abnormalities, 516 cycles were reported for monogenic diseases, 137 cycles were reported for sexing for X-linked diseases, 1722 cycles were reported for preimplantation genetic screening (PGS) and 80 cycles were reported for social sexing. Data VI is compared to the cumulative data for data collections I-V.


Assuntos
Doenças Genéticas Inatas/diagnóstico , Taxa de Gravidez , Diagnóstico Pré-Implantação , Aborto Espontâneo/diagnóstico , Aberrações Cromossômicas , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Humanos , Recém-Nascido , Masculino , Gravidez , Resultado da Gravidez , Pré-Seleção do Sexo
19.
Hum Reprod ; 22(4): 905-11, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17178746

RESUMO

This paper defines a human embryo from a biological standpoint that takes into account emerging technologies in reproductive science. The paper does not consider legal, moral, religious or social views. As the definition of a human embryo must reflect the multifactorial processes of development, an approach has been adopted which combines recognition of observed events with potential for further development. This acknowledges that fertilization and development are not static processes, and as such embryo status can only be defined by observation of specific markers. The following biological definition of 'human embryo' is proposed. A human embryo is a discrete entity that has arisen from either: the first mitotic division when fertilization of a human oocyte by a human sperm is complete or any other process that initiates organized development of a biological entity with a human nuclear genome or altered human nuclear genome that has the potential to develop up to, or beyond, the stage at which the primitive streak appears, and has not yet reached 8 weeks of development since the first mitotic division.


Assuntos
Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário , Fertilização in vitro , Fertilização , Vida , Terminologia como Assunto , Início da Vida Humana , DNA/metabolismo , Feto , Humanos , Fatores de Tempo
20.
Acta Diabetol ; 43(1): 6-13, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16710643

RESUMO

Repaglinide is a prandial glucose regulator indicated for management of type 2 diabetes. This post-marketing study used the observational cohort technique of prescription-event monitoring (PEM) to monitor safety of repaglinide prescribed in primary care in England. Patients were identified from dispensed prescriptions issued by general practitioners (GPs) between December 1998 and January 2001. Demographic and clinical event data were collected from questionnaires posted to GPs at least six months after the date of first prescription for each patient. The cohort consisted of 5731 patients [median age 60 (IQR 51-68), 49.9% male]. Event incidence densities (IDs) [no. 1st reports/1000 patient-months of exposure] were calculated for all events reported. The most frequently recorded clinical events in the first month were diarrhoea (ID(1) 10.3), malaise/lassitude (ID(1) 8.1) and nausea/vomiting (ID(1) 7.9). The most frequently reported reason for stopping was 'not effective' (647), with the most common clinical reasons being diarrhoea (60), malaise/lassitude (55) and intolerance (54). One hundred and thirteen adverse drug reactions (ADRs) were reported, with the most frequently specified being diarrhoea (10), abdominal pain (10) and nausea/vomiting (9). We concluded that repaglinide is generally well tolerated when used in general practice in England and did not identify any serious unrecognised adverse events.


Assuntos
Carbamatos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Prescrições de Medicamentos/normas , Medicina de Família e Comunidade , Hipoglicemiantes/uso terapêutico , Piperidinas/uso terapêutico , Idoso , Carbamatos/efeitos adversos , Causas de Morte , Estudos de Coortes , Diabetes Mellitus Tipo 2/mortalidade , Inglaterra , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Lactente , Pessoa de Meia-Idade , Piperidinas/efeitos adversos , Gravidez , Segurança , Medicina Estatal , Análise de Sobrevida , Transtornos da Visão/induzido quimicamente
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