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2.
Hum Reprod ; 35(3): 583-594, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32161952

RESUMO

STUDY QUESTION: Does the method of fertilisation improve reproductive outcomes in poor ovarian response (POR) cycles when compared to all other ovarian response categories in the absence of male factor subfertility? SUMMARY ANSWER: ICSI does not confer any benefit in improving the clinical pregnancy or live birth (LB) outcome in autologous ovarian response cycles in the absence of male factor subfertility when compared to IVF. WHAT IS KNOWN ALREADY: ICSI is associated with an improved outcome when compared to IVF in patients with severe male factor subfertility. STUDY DESIGN, SIZE, DURATION: A retrospective study involving 1 376 454 ART cycles, of which 569 605 (41.4%) cycles fulfilled the inclusion and exclusion criteria for all autologous ovarian response categories: 272 433 (47.8%) IVF cycles and 297 172 (52.2%) ICSI cycles. Of these, the POR cohort represented 62 641 stimulated fresh cycles (11.0%): 33 436 (53.4%) IVF cycles and 29 205 (46.6%) ICSI cycles. PARTICIPANTS/MATERIALS, SETTING, METHOD: All cycles recorded on the anonymised Human Fertilisation and Embryology Authority (HFEA) registry database between 1991 and 2016 were analysed. All fresh cycles with normal sperm parameters, performed after 1998 were included: frozen cycles, donor oocyte and sperm usage, intrauterine insemination cycles, preimplantation genetic testing (PGT) for aneuploidies (PGT-A), PGT for monogenic/single gene defects (PGT-M), PGT for chromosomal structural arrangements (PGT-SR) cycles, where the reason for stimulation was for storage and unstimulated cycles were excluded. MAIN RESULTS AND THE ROLE OF CHANCE: ICSI did not confer any benefit in improving the LB outcome when compared to conventional IVF per treatment cycle (PTC), when adjusted for female age, number of previous ART treatment cycles, number of previous live births through ART, oocyte yield, stage of transfer, method of fertilisation and number of embryos transferred in the POR cohort (adjusted odds ratio [a OR] 1.03, 99.5% confidence interval [CI] 0.96-1.11, P = 0.261) and all autologous ovarian response categories (aOR 1.00, 99.5% CI 0.98-1.02, P = 0.900). The mean fertilisation rate was statistically lower for IVF treatment cycles (64.7%) when compared to ICSI treatment cycles (67.2%) in the POR cohort (mean difference -2.5%, 99.5% CI -3.3 to -1.6, P < 0.001). The failed fertilisation rate was marginally higher in IVF treatment cycles (17.3%, 95% binomial exact 16.9 to 17.7%) when compared to ICSI treatment cycles (17.0%, 95% binomial exact 16.6 to 17.4%); however, this did not reach statistical significance (P = 0.199). The results followed a similar trend when analysed for all autologous ovarian response categories with a higher rate of failed fertilisation in IVF treatment cycles (4.8%, 95% binomial exact 4.7 to 4.9%) when compared to ICSI treatment cycles (3.2%, 95% binomial exact 3.1 to 3.3%) (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: The quality of data is reliant on the reporting system. Furthermore, success rates through ART have improved since 1991, with an increased number of blastocyst-stage embryo transfers. The inability to link the treatment cycle to the individual patient meant that we were unable to calculate the cumulative LB outcome per patient. WIDER IMPLICATIONS OF THE FINDINGS: This is the largest study to date which evaluates the impact of method of fertilisation in the POR patient and compares this to all autologous ovarian response categories. The results demonstrate that ICSI does not confer any benefit in improving reproductive outcomes in the absence of male factor subfertility, with no improvement seen in the clinical pregnancy or LB outcomes following a fresh treatment cycle. STUDY FUNDING/COMPETING INTEREST(S): The study received no funding. C.M.B. is a member of the independent data monitoring group for a clinical endometriosis trial by ObsEva. He is on the scientific advisory board for Myovant and medical advisory board for Flo Health. He has received research grants from Bayer AG, MDNA Life Sciences, Volition Rx and Roche Diagnostics as well as from Wellbeing of Women, Medical Research Council UK, the NIH, the UK National Institute for Health Research and the European Union. He is the current Chair of the Endometriosis Guideline Development Group for ESHRE and was a co-opted member of the Endometriosis Guideline Group by the UK National Institute for Health and Care Excellence (NICE). I.G. has received research grants from Bayer AG, Wellbeing of Women, the European Union and Finox. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Infertilidade , Injeções de Esperma Intracitoplásmicas , Coeficiente de Natalidade , Feminino , Fertilização in vitro , Humanos , Nascido Vivo , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
3.
J Environ Sci Eng ; 50(4): 249-54, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19697758

RESUMO

Sorption capacity of different parts of Eichhornia crassipes, such as rhizome, root, lamina and petiole on basic aurophine-o was studied in a batch system. The equilibrium uptake capacity was observed as 13.65 mg/g (using root), 13.5 mg/g (using lamina), 12.9 mg/g (using rhizome) and 12.75 mg/g (using petiole). It was observed that the equilibrium dye uptake capacity using root was found to be more when compared to all other E. crassipes parts used in the present investigation. The shortcut equations developed are accurate and can be used in the place of experimental data. The shortcut equations form the basis for further research. The intra particle diffusion coefficient (K(i)) and effective diffusion coefficient (D(i)) were evaluated for the removal of dye using root, which were found to be more when compared to all other parts of E. crassipes studied such as, lamina, rhizome and petiole.


Assuntos
Corantes/química , Corantes/metabolismo , Eichhornia/química , Eichhornia/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Corantes/isolamento & purificação , Simulação por Computador , Resíduos Industriais/prevenção & controle , Cinética , Taxa de Depuração Metabólica , Modelos Biológicos , Modelos Químicos , Indústria Têxtil/métodos
4.
Lab Invest ; 41(3): 198-205, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-157406

RESUMO

Cardiac myosin was examined during the four pathologic stages of cardiomyopathy in strain BIO 14.6 of Syrian hamsters. It was determined that the Ca2+- and K+-ethylenediaminetetraacetic acid (EDTA)-activated ATPase activities of ventricular myosin were significantly reduced during the final stage of the inherited disease. One- and 2-dimensional gel electrophoresis of myosin samples at all stages failed to yield any evidence for a change in the subunit structure of myosin based on light chain number, molecular weight, and per cent composition. The final stage of the disease was characterized by altered protein metabolism. The rates of synthesis and degradation were both altered in the diseased tissue, and a net loss of myosin resulting from a substantial increase in the rate of degradation.


Assuntos
Cardiomiopatias/metabolismo , Miocárdio/metabolismo , Miosinas/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Cricetinae , Eletroforese em Gel de Poliacrilamida , Espaço Extracelular/metabolismo , Marcação por Isótopo , Cinética , Masculino , Fenilalanina/sangue , Fenilalanina/metabolismo
6.
Proc Natl Acad Sci U S A ; 73(6): 1941-4, 1976 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1064864

RESUMO

A potent polypeptide inhibitor of chymotrypsin has been purified from Russett Burbank potatoes. The inhibitor has no effect on bovine carboxypeptidases A or B but exhibits homology with a carboxypeptidase inhibitor that is also present in potato tubers. The chymotrypsin inhibitor has a molecular weight of approximately 5400 as estimated by gel filtration, amino acid analysis, and titration with chymotrypsin. The polypeptide chain consists of 49 amino acid residues, of which six are half-cystine, forming three disulfide bonds. Its size is similar to that of the carboxypeptidase inhibitor, which contains 39 amino acid residues and also has three disulfide bridges. In immunological double diffusion assays, the chymotrypsin inhibitor and the carboxypeptidase inhibitor do not crossreact; however, automatic Edman degradation of reduced and alkylated derivatives of the chymotrypsin inhibitor, yielding a partial sequence of 18 amino acid residues at the NH2-terminus, reveals a similarity in sequence to that of the carboxypeptidase inhibitor. Thus, inhibitors directed toward two distinct classes of proteases, the serine endopeptidases and the metallocarboxypeptidases, appear to have evolved from a common ancestor.


Assuntos
Evolução Biológica , Carboxipeptidases/antagonistas & inibidores , Quimotripsina/antagonistas & inibidores , Inibidores Enzimáticos/análise , Sequência de Aminoácidos , Aminoácidos/análise , Inibidores Enzimáticos/isolamento & purificação , Cinética , Peso Molecular , Plantas/análise , Inibidores da Tripsina/análise , Inibidores da Tripsina/isolamento & purificação
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