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1.
J Assist Reprod Genet ; 38(10): 2663-2670, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34535847

RESUMO

PURPOSE: A deep learning artificial intelligence (AI) algorithm has been demonstrated to outperform embryologists in identifying euploid embryos destined to implant with an accuracy of 75.3% (1). Our aim was to evaluate the performance of highly trained embryologists in selecting top quality day 5 euploid blastocysts with and without the aid of a deep learning algorithm. MATERIALS AND METHODS: A non-overlapping series of 200 sets of day 5 euploid embryo images with known implantation outcomes was distributed to 17 highly trained embryologists. One embryo in each set was known to have implanted and one failed implantation. They were asked to select which embryo to transfer from each set. The same 200 sets of embryos, with indication of which embryo in each set had been identified by the algorithm as more likely to implant was then distributed. Chi-squared, t-test, and receiver operating curves were performed to compare the embryologist performeance with and without AI. RESULTS: Fourteen embryologists completed both assessments. Embryologists provided with AI results selected successfully implanted embryos in 73.6% of cases compared to 65.5% for those selected using visual assessments alone (p < 0.001). All embryologists improved in their ability to select embryos with the aid of the AI algorithm with a mean percent improvement of 11.1% (range 1.4% to 15.5%). There were no differences in degree of improvement by embryologist level of experience (junior, intermediate, senior). CONCLUSIONS: The incorporation of an AI framework for blastocyst selection enhanced the performance of trained embryologists in identifying PGT-A euploid embryos destined to implant.


Assuntos
Algoritmos , Inteligência Artificial , Blastocisto/classificação , Blastocisto/citologia , Técnicas de Apoio para a Decisão , Implantação do Embrião , Fertilização in vitro/métodos , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
2.
J Assist Reprod Genet ; 38(12): 3223-3232, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34704166

RESUMO

PURPOSE: We sought to determine whether pregnancies conceived in those with male factor infertility have unique placental pathology profiles compared to those undergoing infertility treatments for other indications. METHODS: This was a retrospective cohort study of placental pathology from 464 live births conceived from autologous fresh IVF cycles at an academic fertility center from 2004 to 2017. Placental pathology was compared between live births arising from patients with male factor infertility alone and those with another infertility diagnosis. Placental outcomes were compared with parametric or non-parametric tests; logistic regression was performed to account for potential confounders. RESULTS: Compared to cycles performed for a non-male factor diagnosis, male factor infertility cycles had a higher mean paternal age (38.2 years vs. 36.5 years, p < 0.001), a higher female mean BMI (24.3 vs. 23.3 kg/m2, p = 0.01), and a lower day 3 follicle stimulating hormone (FSH) level (6.8 vs. 7.3 IU/mL, p = 0.02). The mean numbers of embryos transferred, and day of transfer were similar between groups, and more cycles used ICSI in the male factor infertility group (90.6% vs. 22.5%, p < 0.001). Placental pathology in our adjusted model was similar between the male factor and non-male factor groups. In our unadjusted subgroup analysis, cycles for male factor using ICSI appeared to lead to more small placentas by weight compared to cycles performed with conventional insemination (45.8% < 10th percentile vs. 18.8%, p = 0.04). CONCLUSION: Male factor infertility is not associated with significantly different placental pathology compared to other infertility diagnoses.


Assuntos
Infertilidade Masculina/patologia , Doenças Placentárias/patologia , Placenta/patologia , Adulto , Peso ao Nascer/fisiologia , Transferência Embrionária/métodos , Feminino , Fertilização/fisiologia , Fertilização in vitro/métodos , Humanos , Nascido Vivo , Masculino , Homens , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
3.
Hum Reprod ; 35(1): 24-31, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31960907

RESUMO

STUDY QUESTION: Is there an effect of male factor infertility (MFI) on either early or late morphokinetic parameters obtained during embryonic culture to blastocyst stage in a time-lapse imaging (TLI) incubator? SUMMARY ANSWER: Neither mild nor severe MFI had an impact on overall time to blastocyst or duration of individual cleavage stages in the total embryo population. WHAT IS KNOWN ALREADY: Prior studies have suggested that paternal DNA and sperm quality affect embryo morphokinetic parameters, but the impact of MFI is not fully understood. STUDY DESIGN, SIZE, DURATION: This retrospective cohort study, at a major academic fertility centre, included 536 couples (women, ≤44 years of age) undergoing IVF between September 2013 and September 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data from 4126 embryos cultured to the blastocyst stage in a TLI-monitored incubator were retrospectively reviewed. Embryos derived from the sperm of men with MFI were compared with those derived from patients with other infertility diagnoses. Generalized fixed and random effects models, t-test and χ2 were used as appropriate. MAIN RESULTS AND THE ROLE OF CHANCE: Couples with MFI had a higher rate of ICSI utilization and fewer usable embryos on average, and the men were older compared with couples with other diagnoses. Additionally, the women in MFI couples were younger and had higher antral follicle counts (AFCs) and higher anti-Müllerian hormone (AMH) levels compared with the other women undergoing IVF. When controlling for maternal and paternal ages, AMH and fertilization method (conventional IVF versus ICSI), neither mild nor severe MFI affected duration of individual cleavage stages or overall time to the blastocyst stage, when all or only usable embryos were examined (coefficient 0.44 hours in all embryos, P = 0.57; coefficient 0.39 hours in usable embryos, P = 0.60). Whether the sperm was surgically extracted similarly had no significant effect on embryo morphokinetic parameters. When the fertilization method was assessed independently, ICSI lengthened the overall time to blastocyst stage by 1.66 hours (P = 0.03) on average, primarily due to an increase in duration of the time from 5-cell embryo stage to early blastulation (P5SB). LIMITATIONS, REASONS FOR CAUTION: This large cohort study avoided embryo selection bias due to random assignment of embryos to the TLI incubators. However, our findings may not be generalizable to groups under-represented in our clinic population. Future studies should also evaluate the impact of male hormonal status and detailed sperm morphology, such as head versus flagellum defects, on embryo morphokinetic development. WIDER IMPLICATIONS OF THE FINDINGS: Our findings suggest that the fertilization method rather than MFI per se impacts time to early blastulation. The clinical implications of this effect on embryo development warrant further investigation. STUDY FUNDING/COMPETING INTEREST(S): There were no sources of funding for this study. There are no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Blastocisto , Técnicas de Cultura Embrionária , Estudos de Coortes , Feminino , Fertilização in vitro , Humanos , Masculino , Estudos Retrospectivos , Imagem com Lapso de Tempo
4.
J Assist Reprod Genet ; 35(5): 879-884, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29589293

RESUMO

PURPOSE: To evaluate the differences in implantation and pregnancy rates when embryo transfer occurs on D2 versus D3 in women with a low yield of fertilized oocytes. METHODS: A total of 156 IVF/ICSI cycles from 141 women at an academic fertility center were analyzed in a retrospective fashion. Women with a low number of fertilized oocytes (≤ 2 two pronuclei (2PN) stage zygotes) who had their fresh embryo transfer on D2 or D3 were included in the study. Positive pregnancy test per IVF cycle (PPT), clinical pregnancy rate (CPR), spontaneous abortion rate (SABR), and implantation rate (IMPR) were the main outcome measures assessed. Mann-Whitney U test and χ2 test were used as appropriate. A generalized linear mixed effect model adjusted for relevant covariates was conducted. P < 0.05 was considered significant. RESULTS: Patients having their embryo transfer on D2, when compared to those who had a D3 embryo transfer, experienced similar PPT [30.8 vs. 28.2%, respectively; adjusted OR (95%CI): 0.49 (0.16, 1.52)], CPR [26.9 vs. 25.6%, respectively; adjusted OR (95%CI): 0.44 (0.12, 1.67)], and IMPR [17.3 vs. 16.7%, respectively; adjusted ß (95%CI) - 5.6% (- 15.0, 3.9)]. CONCLUSION: Our findings suggest that transferring embryos on D2 versus D3 in women with a limited number of 2PN stage zygotes does not affect early pregnancy outcomes. These results indicate that there can be some flexibility in scheduling the day of transfer at the convenience of both the patient and the center.


Assuntos
Transferência Embrionária/métodos , Fertilização in vitro/métodos , Aborto Espontâneo , Adulto , Implantação do Embrião , Feminino , Humanos , Recuperação de Oócitos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Fatores de Tempo
5.
Hum Reprod ; 25(3): 613-22, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20047936

RESUMO

BACKGROUND: Despite advances in in vitro manipulation of preimplantation embryos, there is still a reduction in the quality of embryos produced leading to lower pregnancy rates compared with embryos produced in vivo. We hypothesized that a dynamic microfunnel embryo culture system would enhance outcomes by better mimicking the fluid-mechanical and biochemical stimulation embryos experience in vivo from ciliary currents and oviductal contractions. METHODS AND RESULTS: Mouse embryos were cultured in microdrop-static control, microfunnel-static control or microfunnel-dynamic conditions with microfluidics. All groups tested had greater than 90% total blastocyst development from zygotes after 96 h culture. Blastocyst developmental stage was significantly enhanced (P < 0.01) under dynamic microfunnel culture conditions as evidenced by an increased percentage of hatching or hatched blastocysts (Microdrop-control 31%; Microfunnel-control 23%; Microfunnel-pulsatile 71%) and significantly higher (P < 0.01) average number of cells per blastocyst (Microdrop-control 67 +/- 3; Microfunnel-control 60 +/- 3; Microfunnel-pulsatile 109 +/- 5). Blastocyst cell numbers in dynamic microfunnel cultures (109 +/- 5) more closely matched numbers obtained from in vivo grown blastocysts (144 +/- 9). Importantly, dynamic microfunnel culture significantly improved embryo implantation and ongoing pregnancy rates over static culture to levels approaching that of in utero derived preimplantation embryos. CONCLUSIONS: The improved pregnancy outcomes along with the simple and user-friendly design of the microfluidic/microfunnel system has potential to alleviate many inefficiencies in embryo production for biomedical research, genetic gain in domestic species and assisted reproductive technologies in humans.


Assuntos
Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/fisiologia , Microfluídica , Animais , Feminino , Camundongos , Gravidez , Taxa de Gravidez
6.
J Mol Biol ; 308(4): 765-82, 2001 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-11350173

RESUMO

AFP1 is a recently discovered anti-fungal, chitin-binding protein from Streptomyces tendae Tü901. Mature AFP1 comprises 86 residues and exhibits limited sequence similarity to the cellulose-binding domains of bacterial cellulases and xylanases. No similarity to the Cys and Gly-rich domains of plant chitin-binding proteins (e.g. agglutinins, lectins, hevein) is observed. AFP1 is the first chitin-binding protein from a bacterium for which anti-fungal activity was shown. Here, we report the three-dimensional solution structure of AFP1, determined by nuclear magnetic resonance spectroscopy. The protein contains two antiparallel beta-sheets (five and four beta-strands each), that pack against each other in a parallel beta-sandwich. This type of architecture is conserved in the functionally related family II of cellulose-binding domains, albeit with different connectivity. A similar fold is also observed in other unrelated proteins (spore coat protein from Myxococcus xanthus, beta-B2 and gamma-B crystallins from Bos taurus, canavalin from Jack bean). AFP1 is therefore classified as a new member of the betagamma-crystallin superfamily. The dynamics of the protein was characterized by NMR using amide 15N relaxation and solvent exchange data. We demonstrate that the protein exhibits an axially symmetric (oblate-like) rotational diffusion tensor whose principal axis coincides to within 15 degrees with that of the inertial tensor. After completion of the present structure of AFP1, an identical fold was reported for a Streptomyces killer toxin-like protein. Based on sequence comparisons and clustering of conserved residues on the protein surface for different cellulose and chitin-binding proteins, we postulate a putative sugar-binding site for AFP1. The inability of the protein to bind short chitin fragments suggests that certain particular architectural features of the solid chitin surface are crucial for the interaction.


Assuntos
Antifúngicos/química , Antifúngicos/metabolismo , Proteínas de Bactérias , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Quitina/metabolismo , Streptomyces/química , Sequência de Aminoácidos , Sítios de Ligação , Celulase/química , Quitina/análogos & derivados , Quitina/química , Difusão , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Maleabilidade , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Rotação , Alinhamento de Sequência , Soluções , Eletricidade Estática , Xilano Endo-1,3-beta-Xilosidase , Xilosidases/química
7.
FEMS Microbiol Lett ; 76(1-2): 185-90, 1992 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1427000

RESUMO

Streptomyces tendae Tü901 produces nikkomycins belonging to the nucleoside peptide antibiotics. Mutants defective in histidine catabolism were isolated and characterized with regard to their histidine ammonium-lyase activity and antibiotic synthesis. In the histidine ammonialyase-negative mutant hut-11 which was unimpaired in nikkomycin production histidine aminotransferase activity was detected as an additional histidine metabolizing enzyme. A protein exhibiting histidine aminotransferase activity could be demonstrated on non-denaturing gels of hut-11 crude extracts. Using optimized assay conditions, histidine aminotransferase activity was investigated in the strain hut-11 during growth in nikkomycin production medium. Maximal activity was reached at the end of exponential growth prior to nikkomycin production. In the presence of bromopyruvate, an effective inhibitor of histidine aminotransferase activity in vitro, production of nikkomycin Z and X was markedly reduced in hut-11.


Assuntos
Aminoglicosídeos , Antibacterianos/biossíntese , Streptomyces/metabolismo , Transaminases/metabolismo , Cinética , Mutação , Piruvatos/farmacologia , Streptomyces/genética , Transaminases/antagonistas & inibidores
8.
J Antibiot (Tokyo) ; 52(2): 102-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10344563

RESUMO

The previously described Streptomyces tendae nikC::aph mutant was used to mutasynthesize nikkomycins Bx and Bz. The mutant is deficient in L-lysine 2-aminotransferase, which transaminates lysine to form piperideine 2-carboxylate, the precursor of the peptidyl side chain of the biologically active nikkomycins I, J, X, and Z, and is therefore unable to produce these nikkomycins. The mutant accumulates the biologically inactive biosynthetic nucleoside precursors nikkomycins Cx and Cz. Resting cell cultures of the mutant fed with benzoic acid produced the biologically active nikkomycins Bx and Bz, which contain 2-amino-4-hydroxy-3-methyl-4-(4'-hydroxyphenyl)butanoic acid as the peptidyl side chain. The structures of nikkomycins Bx and Bz were confirmed by mass spectrometry and NMR. Nikkomycins Bx and Bz exhibit significantly higher pH stability than their analogues nikkomycins X and Z.


Assuntos
Aminoglicosídeos , Antibacterianos/biossíntese , Streptomyces/genética , Streptomyces/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Mutação , Transaminases/genética , Transaminases/metabolismo
9.
J Antibiot (Tokyo) ; 53(4): 385-92, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10866220

RESUMO

The nikO gene encoding a putative enolpyruvyl transferase has been identified within the Streptomyces tendae Tü901/8c nikkomycin gene cluster. nikO encodes a deduced protein of 471 amino acid residues which exhibits significant sequence similarity to UDP-N-acetylglucosamine enolpyruvyl transferase and 5-enol-pyruvylshikimate 3-phosphate synthase from various origin. The nikO gene was inactivated by inserting a kanamycin resistance cassette; the mutant did not produce biologically active nikkomycins I, J, X, and Z nor the nucleoside moieties, nikkomycins C(x) and C(z), but accumulated the novel component RT 2.0. RT 2.0 has been isolated from culture filtrate and its structure was determined by using mass spectrometry and NMR analyses as ribofuranosyl-4-formyl-4-imidazolone which represents a novel nucleoside. The putative activity of the nikO gene product in nikkomycin biosynthesis will be discussed.


Assuntos
Alquil e Aril Transferases/genética , Aminoglicosídeos , Antibacterianos/biossíntese , Antifúngicos/biossíntese , Plasmídeos/metabolismo , Sequência de Aminoácidos , Antibacterianos/química , Antifúngicos/química , Clonagem Molecular , Biologia Molecular , Dados de Sequência Molecular , Streptomyces/genética
10.
J Antibiot (Tokyo) ; 42(6): 913-8, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2737950

RESUMO

To isolate Streptomyces tendae mutants blocked in the biosynthesis of the nikkomycin nucleoside base 4-formyl-4-imidazoline-2-one, an assay was developed to detect the formation of nikkomycins containing this base during growth on solid medium. The assay is based on the reaction of the 4-formylimidazolone structure of nikkomycins with the aldehyde reagent barbituric acid leading to red-colored products. Among 18,000 N-methyl-N'-nitro-N-nitrosoguanidine treated clones tested in the barbituric acid assay, we isolated one mutant which was incapable of forming any nikkomycins containing the 4-formylimidazolone base (nikkomycins Cx, X and I) but instead produced nikkomycins containing uracil (nikkomycins C, Z and J). In addition, we isolated strains with mutations affecting the biosynthesis of 2-amino-4-hydroxy-4-(5-hydroxy-2-pyridyl)-3-methylbutyric acid, the unusual amino acid of nikkomycins Z, X, J and I. By analyzing colonies derived from single spores or protoplasts of S. tendae Tü901/395, a mutant producing besides nikkomycins Z, X, J and I, also nikkomycins Kz/Kx and Oz/Ox, we obtained strains which only formed nikkomycins Kz/Kx and Oz/Ox with 2-amino-4-hydroxy-4-(2-pyridyl)butyric acid and 2-amino-4-hydroxy-4-(5-hydroxy-2-pyridyl)-butyric acid as amino acids. Mutation of such a strain (Tü901/395-11) by UV365nm in the presence of 8-methoxypsoralen and selection of S-2-aminoethyl-L-cysteine-resistant clones led to the isolation of Tü901/AEC1 and AEC2 which produced exclusively nikkomycins Kz and Kx. According to their nikkomycin spectrum, these strains were blocked at the hydroxylation step occurring at the pyridyl residue during biosynthesis of the nikkomycin amino acid.


Assuntos
Aminoglicosídeos , Antibacterianos/biossíntese , Antifúngicos/biossíntese , Streptomyces/metabolismo , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Mutação , Streptomyces/genética , Streptomyces/isolamento & purificação
11.
J Antibiot (Tokyo) ; 38(1): 9-16, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3972731

RESUMO

Four new dipeptidyl nikkomycins of the Z- and the X-series with a variation in the amino acid moiety of the molecule were isolated from the mutant Streptomyces tendae 901/395 and characterized. Nikkomycins Kz and Kx contain 2-amino-4-hydroxy-4-(2-pyridyl)butyric acid, and nikkomycins Oz and Ox 2-amino-4-hydroxy-4-(5-hydroxy-2-pyridyl)butyric acid. In contrast to nikkomycins Z and X, nikkomycins Kx and Ox are quite stable at alkaline pH and exhibit a lower biological activity against various test organisms. From the mutant S. tendae 901/C37, which is auxotrophic for methionine and threonine, enhanced amounts of two tripeptidyl nikkomycins, Qz and Qx, were produced which are analogues of nikkomycins J and I and contain a homoserine residue instead of glutamic acid. These nikkomycins exhibit a high pH instability.


Assuntos
Aminoglicosídeos , Antibacterianos , Antifúngicos/biossíntese , Streptomyces/metabolismo , Antifúngicos/farmacologia , Quitina Sintase/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Mutação , Nucleosídeos/biossíntese , Nucleosídeos/farmacologia , Streptomyces/genética
12.
J Antibiot (Tokyo) ; 42(5): 711-7, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2722685

RESUMO

Two new nikkomycins were isolated from the fermentation broth of Streptomyces tendae Tü 901/PF 53+-3. These new metabolites, nikkomycins pseudo-Z (psi-Z,1) and pseudo-J (psi-J, 2) differ from the corresponding nikkomycins Z and J by a C-glycosidic bond between C-5 of uracil and C-1' of 5-amino-5-deoxy-D-allo-furanuronic acid instead of an N-glycosidic bond. The structure elucidation was achieved by two-dimensional NMR techniques and mass spectrometry.


Assuntos
Aminoglicosídeos , Antibacterianos , Antifúngicos , Fenômenos Químicos , Físico-Química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Peso Molecular
13.
J Antibiot (Tokyo) ; 43(1): 43-8, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2137814

RESUMO

Two new dipeptidyl nikkomycins of the Z and X type were isolated from the culture broth of Streptomyces tendae TU 901/395-11/32 and characterized. They show a variation in the amino acid moiety of the molecule. Nikkomycin Wz is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to uracil, whereas nikkomycin Wx is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to 4-formyl-4-imidazolin-2-one. The new nikkomycins are good inhibitors of chitin synthetase from Coprinus cinereus but they did not inhibit growth of fungi and yeasts.


Assuntos
Aminoglicosídeos , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Quitina Sintase/antagonistas & inibidores , Glucosiltransferases/antagonistas & inibidores , Streptomyces/metabolismo , Antibacterianos/análise , Antibacterianos/biossíntese , Antifúngicos/análise , Antifúngicos/biossíntese , Cromatografia Líquida de Alta Pressão , Fermentação , Espectroscopia de Ressonância Magnética , Espectrofotometria Ultravioleta
14.
J Antibiot (Tokyo) ; 42(2): 230-5, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2925514

RESUMO

Two new nikkomycins were isolated from the culture broth of Streptomyces tendae Tü 901/PF 53+-3. The new compounds are the dipeptide nikkomycin pseudo-Z (psi Z) and tripeptide nikkomycin pseudo-J (psi J), which are analogues to nikkomycins Z and J. Nikkomycins pseudo-Z and pseudo-J have a C-glycosidic linkage between uracil and 5-amino-5-deoxy-D-allo-furanuronic acid, which is comparable to the C-glycosidic bond in pseudouridine. The new Cc-nucleoside nikkomycins exhibit a lower biological activity than the CN-nucleoside nikkomycins.


Assuntos
Aminoglicosídeos , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Streptomyces/metabolismo , Antibacterianos/farmacologia , Meios de Cultura/análise , Fermentação , Fungos/efeitos dos fármacos , Leveduras/efeitos dos fármacos
15.
J Antibiot (Tokyo) ; 44(6): 626-34, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1906452

RESUMO

Two brominated nikkomycins were produced by enzymatic halogenation of nikkomycin Z in the presence of a nonheme bromoperoxidase isolated from Streptomyces aureofaciens Tü 24. The monobrominated and dibrominated nikkomycin Z derivatives were substituted at the hydroxypyridyl moiety of the N-terminal amino acid of nikkomycin Z at position C-6"' (ZBr) or C-4"' and C-6"' (ZBr2). The brominated nikkomycin Z derivatives had a decreased affinity to chitin synthase of Coprinus cinereus as compared to nikkomycin Z and exhibited a low inhibitory activity towards various fungi and yeasts.


Assuntos
Aminoglicosídeos , Antibacterianos/metabolismo , Antifúngicos/metabolismo , Peroxidases/metabolismo , Streptomyces aureofaciens/enzimologia , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Quitina Sintase/metabolismo , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Coprinus/enzimologia , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Peroxidases/genética , Plasmídeos , Saccharomyces cerevisiae/efeitos dos fármacos , Espectrofotometria Ultravioleta , Streptomyces/genética , Transformação Bacteriana
16.
J Addict Dis ; 14(4): 87-109, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8929935

RESUMO

A heterogeneous and representative sample of 323 homeless individuals in the metropolitan-Denver area with alcohol or other substance abuse problems received a comprehensive array of substance-abuse treatment services. Following treatment, these individuals showed dramatic improvement on average in their (a) levels of alcohol and drug use, (b) housing status, (c) physical and mental health, (d) employment, and (e) quality of life. Those who received more service improved more than those who received less service. These improvements are attributable, at least partly, to the treatment rather than to alternative hypotheses such as spontaneous remission. However, the rate of improvement generally slowed during the six-month follow-up period. A random half of the clients received intensive case management in addition to the other services. Case management marginally increased clients' contacts with addictions counselors, but had little effect on the level of other services received or on the tailoring of services to client needs. As a result, case management also had little, if any, effect on outcomes.


Assuntos
Alcoolismo/reabilitação , Pessoas Mal Alojadas/psicologia , Equipe de Assistência ao Paciente , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adulto , Alcoolismo/psicologia , Administração de Caso , Colorado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Reabilitação Vocacional/psicologia , Apoio Social , Transtornos Relacionados ao Uso de Substâncias/psicologia , Resultado do Tratamento
17.
Theriogenology ; 56(3): 459-69, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11516125

RESUMO

Porcine embryo development in vitro is relatively inefficient compared to other domestic species. Currently, a single culture medium (NCSU23) is the standard for porcine in vitro systems. However, the G1.2/G2.2 sequential culture system has been beneficial for embryo development in other species. The objective of this study was to compare porcine preimplantation embryo development in vitro and subsequent blastocyst viability and metabolic activity using NCSU23 and G1.2/G2.2 culture media. Oocytes were matured in defined TCM199 base medium for 45 to 47 h and fertilized in mTBM for 4 h. Embryos were cultured in either NCSU23 for 146 h or G1.2 medium for 72 h followed by culture in G2.2 medium for an additional 74 h. Blastocyst substrate use was measured using a modification of the hanging drop technique. Culture in NCSU23 resulted in a higher percentage (P < 0.05) of embryo cleavage (74.0%) and blastocyst development (14.6%) than culture in G1.2/G2.2 (67.8% and 7.8%, respectively). Both NCSU23 and G1.2/G2.2 produced blastocysts with similar mean cell numbers (51.5 +/- 4.3 and 47.1 +/- 4.3, respectively), similar glucose use (10.81 +/- 1.39 and 10.12 +/- 1.72 pmol/embryo/3 h, respectively) and pyruvate use (1.08 +/- 0.056 and 0.88 +/- 0.048 pmol/embryo/3 h, respectively). These data indicate that a sequential culture system can support porcine embryo development in vitro without compromising embryo viability. However, the G1.2/G2.2 system was not as effective as NCSU23 in supporting blastocyst development. Sequential media should be formulated specifically for porcine embryos to improve embryonic cleavage and blastocyst development.


Assuntos
Blastocisto/fisiologia , Fertilização in vitro/veterinária , Suínos/embriologia , Animais , Blastocisto/metabolismo , Meios de Cultura/farmacologia , Feminino , Fertilização in vitro/métodos , Glucose/metabolismo , Masculino , Oócitos/metabolismo , Oócitos/fisiologia , Gravidez , Ácido Pirúvico/metabolismo , Distribuição Aleatória , Estatísticas não Paramétricas , Suínos/metabolismo
18.
Theriogenology ; 55(9): 1933-45, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11414497

RESUMO

Effective activation protocols that can be used during nuclear transfer investigations in goats need to be developed. We compared the development of IVF goat embryos with those of nonfertilized parthogenetically developing oocytes activated by treatment with either ionomycin or ethanol, both followed by immediate exposure to 6-diethylaminopurine (6-DMAP). Cumulus oocyte complexes (COCs) recovered from abattoir goat ovaries were either matured in a conventional laboratory incubator or placed in pre-equilibrated maturation medium and shipped overnight in a battery-operated dry incubator to another laboratory. Mature COCs were allocated randomly to one of three treatment groups. Group 1 oocytes (n=169 shipped, n=253 not shipped) were fertilized in vitro at 24 h postmaturation (hpm). The remaining COCs were activated at 28 hpm in either ionomycin (Group 2: n=362 shipped, n=202 not shipped), or ethanol (Group 3: n=263 shipped, n=249 not shipped). Activated oocytes were immediately incubated in 6-DMAP for 4 h. Blastocyst development was evaluated on Day 8 post-insemination/activation. Percent cleavage was comparable in shipped and nonshipped oocytes and in all treatment groups. In both shipped and nonshipped oocytes, parthenotes developing from ionomycin- and ethanol-activated oocytes had significantly greater blastocyst development (P<0.01) compared to IVF embryos (28.5 +/- 3.0, 27.4 +/- 2.8, 10.3 +/- 3.0, respectively for the nonshipped oocytes and 9.9 +/- 2.1, 10.3 +/- 2.4, 3.7 +/- 4.7 respectively for the shipped oocytes). Shipped oocytes had lower blastocyst development compared to nonshipped oocytes in the three treatment groups. The mean blastocyst cell number was not statistically different between shipped and nonshipped oocytes or among treatment groups, suggesting that all were equally viable.


Assuntos
Fertilização in vitro/veterinária , Cabras/embriologia , Partenogênese , Animais , Blastocisto/efeitos dos fármacos , Etanol/farmacologia , Feminino , Ionomicina/farmacologia , Masculino , Oócitos/efeitos dos fármacos , Partenogênese/efeitos dos fármacos , Manejo de Espécimes/veterinária
19.
J Am Coll Health ; 50(2): 81-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11590987

RESUMO

In fall 1996, the University of Colorado at Boulder instituted a ban on beer sales at football games. To evaluate the effects of the ban, the authors collected two types of data: first, they examined the effects of the ban on game-day security incidents; second, they looked at survey data from season ticket holders and students. They administered the surveys after the first two postban seasons to assess ticket holders' attitudes about the new policy. The incident data they found indicated dramatic decreases in arrests, assaults, ejections from the stadium, and student referrals to the judicial affairs office following the ban. Survey data also indicated moderately negative attitudes about the ban among students and some season ticket holders. However, all fans were likely to renew their tickets regardless of their attitudes toward the policy. The study illustrates what can be achieved when alcohol is eliminated from a setting that frequently fosters disorderly and aggressive behaviors.


Assuntos
Alcoolismo/prevenção & controle , Universidades/legislação & jurisprudência , Violência/estatística & dados numéricos , Adolescente , Adulto , Atitude , Colorado , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Esportes , Inquéritos e Questionários
20.
Soz Praventivmed ; 39(2): 67-74, 1994.
Artigo em Alemão | MEDLINE | ID: mdl-8191793

RESUMO

With the data of the German National Health Survey the question is discussed, if self-reports on diseases, gained in a survey, are useful for estimating prevalences within the German population. Self-reports on myocardial infarction serve as an example for examining the reliability and plausibility of such data. The prevalence rate for myocardial infarction in this survey is compared with prevalence rates of other data sources as the MONICA-register and surveys. Because these other data sources have some problems and deficits according to their validity too, the value of self-reports on diseases from the National Health Survey is seen positively for establishing a health reporting system.


Assuntos
Coleta de Dados/métodos , Infarto do Miocárdio/epidemiologia , Adulto , Idoso , Doença das Coronárias/epidemiologia , Feminino , Alemanha/epidemiologia , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Inquéritos e Questionários
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