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1.
Anal Biochem ; 654: 114801, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35803298

RESUMO

We report a novel Fluorescence Resonance Energy Transfer (FRET) immunosensor for sensitive detection of whole cell H. pylori, a causative organism for gastric carcinoma. Highly fluorescent and well-dispersed functionalized carbon dots (FCDs) were synthesized and chemically conjugated with anti-H. pylori antibody to fabricate a fluorescent probe (FCDs-Ab). The fluorescence of FCDs-Ab gets quenched upon interaction with graphene oxide (GO), whereas in presence of H. pylori, the interaction between the FCD-Ab and GO gets interrupted and gradual restoration of fluorescence was observed due to the specific affinity and binding of Ab towards H. pylori. The immunosensor was characterized at each step of fabrication. The assay exhibits a linear detection range of 5-107 cells mL-1 with limit of detection (LOD) of 10 cells mL-1 with high specificity and selectivity to target pathogen. The analytical performance of the developed immunosensor was evaluated with different spiked food samples and the substantial recovery validates its potential for risk assessment in food testing, thus ensuring general safety of public health.


Assuntos
Técnicas Biossensoriais , Grafite , Helicobacter pylori , Pontos Quânticos , Anticorpos Antibacterianos , Carbono/química , Transferência Ressonante de Energia de Fluorescência , Grafite/química , Imunoensaio , Limite de Detecção , Pontos Quânticos/química
2.
Health Technol Assess ; 25(68): 1-114, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34821547

RESUMO

TRIAL DESIGN: A randomised, parallel-group, double-blind, placebo-controlled multicentre study with health economic and nested qualitative studies to determine if mifepristone (Mifegyne®, Exelgyn, Paris, France) plus misoprostol is superior to misoprostol alone for the resolution of missed miscarriage. METHODS: Women diagnosed with missed miscarriage in the first 14 weeks of pregnancy were randomly assigned (1 : 1 ratio) to receive 200 mg of oral mifepristone or matched placebo, followed by 800 µg of misoprostol 2 days later. A web-based randomisation system allocated the women to the two groups, with minimisation for age, body mass index, parity, gestational age, amount of bleeding and randomising centre. The primary outcome was failure to pass the gestational sac within 7 days after randomisation. The prespecified key secondary outcome was requirement for surgery to resolve the miscarriage. A within-trial cost-effectiveness study and a nested qualitative study were also conducted. Women who completed the trial protocol were purposively approached to take part in an interview to explore their satisfaction with and the acceptability of medical management of missed miscarriage. RESULTS: A total of 711 women, from 28 hospitals in the UK, were randomised to receive either mifepristone plus misoprostol (357 women) or placebo plus misoprostol (354 women). The follow-up rate for the primary outcome was 98% (696 out of 711 women). The risk of failure to pass the gestational sac within 7 days was 17% (59 out of 348 women) in the mifepristone plus misoprostol group, compared with 24% (82 out of 348 women) in the placebo plus misoprostol group (risk ratio 0.73, 95% confidence interval 0.54 to 0.98; p = 0.04). Surgical intervention to resolve the miscarriage was needed in 17% (62 out of 355 women) in the mifepristone plus misoprostol group, compared with 25% (87 out of 353 women) in the placebo plus misoprostol group (risk ratio 0.70, 95% confidence interval 0.52 to 0.94; p = 0.02). There was no evidence of a difference in the incidence of adverse events between the two groups. A total of 42 women, 19 in the mifepristone plus misoprostol group and 23 in the placebo plus misoprostol group, took part in an interview. Women appeared to have a preference for active management of their miscarriage. Overall, when women experienced care that supported their psychological well-being throughout the care pathway, and information was delivered in a skilled and sensitive manner such that women felt informed and in control, they were more likely to express satisfaction with medical management. The use of mifepristone and misoprostol showed an absolute effect difference of 6.6% (95% confidence interval 0.7% to 12.5%). The average cost per woman was lower in the mifepristone plus misoprostol group, with a cost saving of £182 (95% confidence interval £26 to £338). Therefore, the use of mifepristone and misoprostol for the medical management of a missed miscarriage dominated the use of misoprostol alone. LIMITATIONS: The results from this trial are not generalisable to women diagnosed with incomplete miscarriage and the study does not allow for a comparison with expectant or surgical management of miscarriage. FUTURE WORK: Future work should use existing data to assess and rank the relative clinical effectiveness and safety profiles for all methods of management of miscarriage. CONCLUSIONS: Our trial showed that pre-treatment with mifepristone followed by misoprostol resulted in a higher rate of resolution of missed miscarriage than misoprostol treatment alone. Women were largely satisfied with medical management of missed miscarriage and would choose it again. The mifepristone and misoprostol intervention was shown to be cost-effective in comparison to misoprostol alone. TRIAL REGISTRATION: Current Controlled Trials ISRCTN17405024. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 68. See the NIHR Journals Library website for further project information.


Miscarriage is a common complication of pregnancy, affecting approximately one in four women. Sometimes, medical treatment (i.e. tablets) may be offered to start or speed up the miscarriage process in order for the womb to empty itself. A drug called misoprostol (a tablet that makes the womb contract) is currently recommended for this treatment. However, the addition of another drug called mifepristone [a tablet that reduces pregnancy hormones (Mifegyne®, Exelgyn, Paris, France)] might help the miscarriage to resolve more quickly. Therefore, we carried out the MifeMiso trial to test if mifepristone plus misoprostol is more effective than misoprostol alone in resolving miscarriage within 7 days. Women were randomly allocated by a computer to receive either mifepristone or placebo, followed by misoprostol 2 days later. Neither the women nor their health-care professionals knew which treatment they received. Some women also talked to the researchers about their experiences of taking part in the study. In total, 711 women were randomised to receive either mifepristone plus misoprostol or placebo plus misoprostol. Overall, 83% of women who received mifepristone plus misoprostol had miscarriage resolution within 7 days, compared with 76% of the women who received a placebo plus misoprostol. Surgery was required less often in women who received mifepristone plus misoprostol: 17% of women who received it required surgery, compared with 25% of women who received the placebo. Treatment with mifepristone did not appear to have any negative effects. Treatment with mifepristone plus misoprostol was more cost-effective than misoprostol alone, with an average saving of £182 per woman. Having taken part in the study, most women would choose medical management again and would recommend it to someone they knew who was experiencing a miscarriage.


Assuntos
Aborto Espontâneo , Misoprostol , Aborto Espontâneo/tratamento farmacológico , Análise Custo-Benefício , Feminino , Humanos , Mifepristona/uso terapêutico , Misoprostol/uso terapêutico , Gravidez , Avaliação da Tecnologia Biomédica
3.
Eur J Obstet Gynecol Reprod Biol ; 261: 211-216, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33971384

RESUMO

OBJECTIVE: To characterise the endometrial transcriptomic profiles of women who suffered recurrent miscarriage and to set the foundation for the development of an endometrial receptivity test that could predict the fate of subsequent pregnancies. STUDY DESIGN: This was a prospective multicentre cohort study performed at the Tommy's National Centre for Miscarriage Research in Birmingham, Saint Mary's Hospital in Manchester and Royal Devon & Exeter Hospital, United Kingdom. The study was conducted between December 2017 and December 2019. Endometrial biopsies were obtained during the window of implantation from 24 women aged 18-35 years, who were not pregnant and regularly menstruating, diagnosed with unexplained recurrent miscarriage by standard investigations as per the ESHRE guidelines. Exclusion criteria included risk factors such as smoking, obesity or hyperprolactinemia. The RNA transcripts abundances were quantified using Kallisto. R packages tximport and DESeq2 were used to summarize count estimates at the gene level and to analyse the differential gene expression. RESULTS: Women who suffered four or more miscarriages had 19 differently expressed genes after adjustment for multiple comparisons. They were related to biological processes such as immunity (HLA-DMA, CCR8, ALOX5), energy production (ATP12A), hormone secretion (CGA), adhesion (CHAD, ADGRF2, AQP5, TBCD, CTNND1, NKD2) and cell proliferation (NCCRP1). Based on 421 differently expressed genes, women who achieved a subsequent live birth displayed an enrichment of processes related to the regulation of cell structure and proliferation, and a depletion of processes related to immunity, trans-membrane transport and coagulation. CONCLUSIONS: Women in the extreme miscarriage cohort had a distinctive endometrial transcriptomic signature compared to women with low order miscarriages. There was a partial overlap with the transcriptome of asynchronous endometrium suggesting the endometrial factor to be a different entity in the context of recurrent miscarriage. Women who achieved a live birth in their subsequent pregnancy displayed an enrichment of genes related to the regulation of cell structure and proliferation, while women who suffered a subsequent miscarriage displayed an enrichment of genes related to immunity, trans-membrane transport and coagulation.


Assuntos
Aborto Habitual , Transcriptoma , Aborto Habitual/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ligação ao Cálcio , Estudos de Coortes , Endométrio , Feminino , ATPase Trocadora de Hidrogênio-Potássio , Humanos , Proteínas Associadas aos Microtúbulos , Gravidez , Estudos Prospectivos , Reino Unido
4.
J Pediatr Adolesc Gynecol ; 34(3): 412-414, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33444778

RESUMO

STUDY OBJECTIVE: To establish the gynecological and reproductive outcomes for girls born with a cloacal anomaly, seen in a pediatric specialist cloaca clinic. DESIGN: Local approval was granted to conduct this review. Outcomes were retrospectively identified using healthcare records. PARTICIPANTS: Girls with known cloacal anomaly, seen in the cloaca clinic between 2009 and 2019, who had attained menarche or received gynecological input. RESULTS: Nine females met the inclusion criteria, who were 12-30 years old. The mean age of menarche was 12 years (SD = 1.29). Two developed obstructed menstruation, requiring surgical intervention. Vaginal stenosis affected all women. Three women underwent revision surgery, and 1 is awaiting surgery. None of the women have attempted a pregnancy, to our knowledge. CONCLUSION: Cloacal anomaly is a rare complex condition. Female individuals with cloacal anomaly require multidisciplinary gynecology specialist care throughout adolescence and adulthood. Provision of a dedicated gynecological service could improve the quality of life of these women.


Assuntos
Cloaca/anormalidades , Qualidade de Vida , Adolescente , Adulto , Criança , Feminino , Ginecologia/métodos , Humanos , Gravidez , Estudos Retrospectivos , Transição para Assistência do Adulto , Adulto Jovem
5.
Hum Fertil (Camb) ; 24(4): 298-303, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31466486

RESUMO

Men with cystic fibrosis are nearly always infertile due to congenital bilateral absence of the vas deferens, but can undergo assisted reproduction. Ill health may influence reproductive choices. This paper reports data on fertility and family formation in CF including the use of assisted reproduction in a total cohort of 205 men (mean age 30.9, range 16.6-64.3 years) studied over a 10-year period. Overall 102 (49.5%) were single, 52 (25.7%) were married, 48 (23.3%) were in long-term heterosexual relationships, and 3 (1.5%) were in same-sex relationships. One (0.5%) was fertile naturally. In total, 30 children were born to 23 (11%) men by assisted reproduction: 4 used donor sperm and 19 had sperm retrieval and intracytoplasmic sperm injection (ICSI). Two men each adopted two children; 15 (7.3%) men were acting as step-fathers to 20 children from their partners' previous relationships. Overall 41 (20%) men had fatherhood roles. ICSI was unsuccessful in 4 men. A further 16 men were referred for fertility treatment but did not proceed. Of the 19 men having children by ICSI, 3 died leaving 4 children. Men with CF face complex decisions when considering their relationships, fertility and fatherhood.


Assuntos
Fibrose Cística , Infertilidade Masculina , Adolescente , Adulto , Criança , Fertilidade , Humanos , Infertilidade Masculina/etiologia , Masculino , Pessoa de Meia-Idade , Injeções de Esperma Intracitoplásmicas , Ducto Deferente , Adulto Jovem
6.
Lancet ; 396(10253): 770-778, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-32853559

RESUMO

BACKGROUND: The anti-progesterone drug mifepristone and the prostaglandin misoprostol can be used to treat missed miscarriage. However, it is unclear whether a combination of mifepristone and misoprostol is more effective than administering misoprostol alone. We investigated whether treatment with mifepristone plus misoprostol would result in a higher rate of completion of missed miscarriage compared with misoprostol alone. METHODS: MifeMiso was a multicentre, double-blind, placebo-controlled, randomised trial in 28 UK hospitals. Women were eligible for enrolment if they were aged 16 years and older, diagnosed with a missed miscarriage by pelvic ultrasound scan in the first 14 weeks of pregnancy, chose to have medical management of miscarriage, and were willing and able to give informed consent. Participants were randomly assigned (1:1) to a single dose of oral mifepristone 200 mg or an oral placebo tablet, both followed by a single dose of vaginal, oral, or sublingual misoprostol 800 µg 2 days later. Randomisation was managed via a secure web-based randomisation program, with minimisation to balance study group assignments according to maternal age (<30 years vs ≥30 years), body-mass index (<35 kg/m2vs ≥35 kg/m2), previous parity (nulliparous women vs parous women), gestational age (<70 days vs ≥70 days), amount of bleeding (Pictorial Blood Assessment Chart score; ≤2 vs ≥3), and randomising centre. Participants, clinicians, pharmacists, trial nurses, and midwives were masked to study group assignment throughout the trial. The primary outcome was failure to spontaneously pass the gestational sac within 7 days after random assignment. Primary analyses were done according to intention-to-treat principles. The trial is registered with the ISRCTN registry, ISRCTN17405024. FINDINGS: Between Oct 3, 2017, and July 22, 2019, 2595 women were identified as being eligible for the MifeMiso trial. 711 women were randomly assigned to receive either mifepristone and misoprostol (357 women) or placebo and misoprostol (354 women). 696 (98%) of 711 women had available data for the primary outcome. 59 (17%) of 348 women in the mifepristone plus misoprostol group did not pass the gestational sac spontaneously within 7 days versus 82 (24%) of 348 women in the placebo plus misoprostol group (risk ratio [RR] 0·73, 95% CI 0·54-0·99; p=0·043). 62 (17%) of 355 women in the mifepristone plus misoprostol group required surgical intervention to complete the miscarriage versus 87 (25%) of 353 women in the placebo plus misoprostol group (0·71, 0·53-0·95; p=0·021). We found no difference in incidence of adverse events between the study groups. INTERPRETATION: Treatment with mifepristone plus misoprostol was more effective than misoprostol alone in the management of missed miscarriage. Women with missed miscarriage should be offered mifepristone pretreatment before misoprostol to increase the chance of successful miscarriage management, while reducing the need for miscarriage surgery. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme.


Assuntos
Aborto Retido/tratamento farmacológico , Mifepristona/uso terapêutico , Misoprostol/uso terapêutico , Ocitócicos/uso terapêutico , Adulto , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Resultado do Tratamento
7.
Health Technol Assess ; 24(33): 1-70, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32609084

RESUMO

BACKGROUND: Progesterone is essential for a healthy pregnancy. Several small trials have suggested that progesterone therapy may rescue a pregnancy in women with early pregnancy bleeding, which is a symptom that is strongly associated with miscarriage. OBJECTIVES: (1) To assess the effects of vaginal micronised progesterone in women with vaginal bleeding in the first 12 weeks of pregnancy. (2) To evaluate the cost-effectiveness of progesterone in women with early pregnancy bleeding. DESIGN: A multicentre, double-blind, placebo-controlled, randomised trial of progesterone in women with early pregnancy vaginal bleeding. SETTING: A total of 48 hospitals in the UK. PARTICIPANTS: Women aged 16-39 years with early pregnancy bleeding. INTERVENTIONS: Women aged 16-39 years were randomly assigned to receive twice-daily vaginal suppositories containing either 400 mg of progesterone or a matched placebo from presentation to 16 weeks of gestation. MAIN OUTCOME MEASURES: The primary outcome was live birth at ≥ 34 weeks. In addition, a within-trial cost-effectiveness analysis was conducted from an NHS and NHS/Personal Social Services perspective. RESULTS: A total of 4153 women from 48 hospitals in the UK received either progesterone (n = 2079) or placebo (n = 2074). The follow-up rate for the primary outcome was 97.2% (4038 out of 4153 participants). The live birth rate was 75% (1513 out of 2025 participants) in the progesterone group and 72% (1459 out of 2013 participants) in the placebo group (relative rate 1.03, 95% confidence interval 1.00 to 1.07; p = 0.08). A significant subgroup effect (interaction test p = 0.007) was identified for prespecified subgroups by the number of previous miscarriages: none (74% in the progesterone group vs. 75% in the placebo group; relative rate 0.99, 95% confidence interval 0.95 to 1.04; p = 0.72); one or two (76% in the progesterone group vs. 72% in the placebo group; relative rate 1.05, 95% confidence interval 1.00 to 1.12; p = 0.07); and three or more (72% in the progesterone group vs. 57% in the placebo group; relative rate 1.28, 95% confidence interval 1.08 to 1.51; p = 0.004). A significant post hoc subgroup effect (interaction test p = 0.01) was identified in the subgroup of participants with early pregnancy bleeding and any number of previous miscarriage(s) (75% in the progesterone group vs. 70% in the placebo group; relative rate 1.09, 95% confidence interval 1.03 to 1.15; p = 0.003). There were no significant differences in the rate of adverse events between the groups. The results of the health economics analysis show that progesterone was more costly than placebo (£7655 vs. £7572), with a mean cost difference of £83 (adjusted mean difference £76, 95% confidence interval -£559 to £711) between the two arms. Thus, the incremental cost-effectiveness ratio of progesterone compared with placebo was estimated as £3305 per additional live birth at ≥ 34 weeks of gestation. CONCLUSIONS: Progesterone therapy in the first trimester of pregnancy did not result in a significantly higher rate of live births among women with threatened miscarriage overall, but an important subgroup effect was identified. A conclusion on the cost-effectiveness of the PRISM trial would depend on the amount that society is willing to pay to increase the chances of an additional live birth at ≥ 34 weeks. For future work, we plan to conduct an individual participant data meta-analysis using all existing data sets. TRIAL REGISTRATION: Current Controlled Trials ISRCTN14163439, EudraCT 2014-002348-42 and Integrated Research Application System (IRAS) 158326. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 33. See the NIHR Journals Library website for further project information.


Miscarriage is a common complication of pregnancy that affects one in five pregnancies. Several small studies have suggested that progesterone, a hormone essential for maintaining a pregnancy, may reduce the risk of miscarriage in women presenting with early pregnancy bleeding. This research was undertaken to test whether or not progesterone given to pregnant women with early pregnancy bleeding would increase the number of live births when compared with placebo (dummy treatment). The women participating in the study had an equal chance of receiving progesterone or placebo, as determined by a computer; one group received progesterone (400 mg twice daily as vaginal pessaries) and the other group received placebo with an identical appearance. Treatment began when women presented with vaginal bleeding, were < 12 weeks of gestation and were found to have at least a pregnancy sac on an ultrasound scan. Treatment was stopped at 16 weeks of gestation, or earlier if the pregnancy ended before 16 weeks. Neither the participants nor their health-care professionals knew which treatment was being received. In total, 23,775 women were screened and 4153 women were randomised to receive either progesterone or placebo pessaries. Altogether, 2972 participants had a live birth after at least 34 weeks of gestation. Overall, the live birth rate in the progesterone group was 75% (1513 out of 2025 participants), compared with 72% (1459 out of 2013 participants) in the placebo group. Although the live birth rate was 3% higher in the progesterone group than in the placebo group, there was statistical uncertainty about this finding. However, it was observed that women with a history of one or more previous miscarriages and vaginal bleeding in their current pregnancy may benefit from progesterone. For women with no previous miscarriages, our analysis showed that the live birth rate was 74% (824 out of 1111 participants) in the progesterone group compared with 75% (840 out of 1127 participants) in the placebo group. For women with one or more previous miscarriages, the live birth rate was 75% (689 out of 914 participants) in the progesterone group compared with 70% (619 out of 886 participants) in the placebo group. The potential benefit appeared to be most strong for women with three or more previous miscarriages, who had a live birth rate of 72% (98 out of 137 participants) in the progesterone group compared with 57% (85 out of 148 participants) in the placebo group. Treatment with progesterone did not appear to have any negative effects.


Assuntos
Aborto Espontâneo/prevenção & controle , Primeiro Trimestre da Gravidez , Progesterona/administração & dosagem , Hemorragia Uterina , Adolescente , Adulto , Análise Custo-Benefício/economia , Método Duplo-Cego , Feminino , Humanos , Parto , Gravidez , Supositórios/administração & dosagem , Reino Unido , Hemorragia Uterina/tratamento farmacológico , Hemorragia Uterina/etiologia , Adulto Jovem
8.
N Engl J Med ; 380(19): 1815-1824, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31067371

RESUMO

BACKGROUND: Bleeding in early pregnancy is strongly associated with pregnancy loss. Progesterone is essential for the maintenance of pregnancy. Several small trials have suggested that progesterone therapy may improve pregnancy outcomes in women who have bleeding in early pregnancy. METHODS: We conducted a multicenter, randomized, double-blind, placebo-controlled trial to evaluate progesterone, as compared with placebo, in women with vaginal bleeding in early pregnancy. Women were randomly assigned to receive vaginal suppositories containing either 400 mg of progesterone or matching placebo twice daily, from the time at which they presented with bleeding through 16 weeks of gestation. The primary outcome was the birth of a live-born baby after at least 34 weeks of gestation. The primary analysis was performed in all participants for whom data on the primary outcome were available. A sensitivity analysis of the primary outcome that included all the participants was performed with the use of multiple imputation to account for missing data. RESULTS: A total of 4153 women, recruited at 48 hospitals in the United Kingdom, were randomly assigned to receive progesterone (2079 women) or placebo (2074 women). The percentage of women with available data for the primary outcome was 97% (4038 of 4153 women). The incidence of live births after at least 34 weeks of gestation was 75% (1513 of 2025 women) in the progesterone group and 72% (1459 of 2013 women) in the placebo group (relative rate, 1.03; 95% confidence interval [CI], 1.00 to 1.07; P = 0.08). The sensitivity analysis, in which missing primary outcome data were imputed, resulted in a similar finding (relative rate, 1.03; 95% CI, 1.00 to 1.07; P = 0.08). The incidence of adverse events did not differ significantly between the groups. CONCLUSIONS: Among women with bleeding in early pregnancy, progesterone therapy administered during the first trimester did not result in a significantly higher incidence of live births than placebo. (Funded by the United Kingdom National Institute for Health Research Health Technology Assessment program; PRISM Current Controlled Trials number, ISRCTN14163439.).


Assuntos
Aborto Espontâneo/prevenção & controle , Complicações na Gravidez/diagnóstico por imagem , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Hemorragia Uterina/tratamento farmacológico , Administração Intravaginal , Adulto , Método Duplo-Cego , Feminino , Humanos , Nascido Vivo , Gravidez , Primeiro Trimestre da Gravidez , Falha de Tratamento
10.
Nature ; 534(7607): 383-6, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27281217

RESUMO

Mitochondrial DNA (mtDNA) mutations are maternally inherited and are associated with a broad range of debilitating and fatal diseases. Reproductive technologies designed to uncouple the inheritance of mtDNA from nuclear DNA may enable affected women to have a genetically related child with a greatly reduced risk of mtDNA disease. Here we report the first preclinical studies on pronuclear transplantation (PNT). Surprisingly, techniques used in proof-of-concept studies involving abnormally fertilized human zygotes were not well tolerated by normally fertilized zygotes. We have therefore developed an alternative approach based on transplanting pronuclei shortly after completion of meiosis rather than shortly before the first mitotic division. This promotes efficient development to the blastocyst stage with no detectable effect on aneuploidy or gene expression. After optimization, mtDNA carryover was reduced to <2% in the majority (79%) of PNT blastocysts. The importance of reducing carryover to the lowest possible levels is highlighted by a progressive increase in heteroplasmy in a stem cell line derived from a PNT blastocyst with 4% mtDNA carryover. We conclude that PNT has the potential to reduce the risk of mtDNA disease, but it may not guarantee prevention.


Assuntos
DNA Mitocondrial/genética , Doenças Mitocondriais/genética , Doenças Mitocondriais/prevenção & controle , Terapia de Substituição Mitocondrial/métodos , Técnicas de Transferência Nuclear , Adulto , Blastocisto/citologia , Blastocisto/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , DNA Mitocondrial/análise , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Meiose , Mitocôndrias/genética , Mitocôndrias/metabolismo , Doenças Mitocondriais/patologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Pesquisa Translacional Biomédica , Adulto Jovem , Zigoto/citologia , Zigoto/metabolismo
11.
Eur J Obstet Gynecol Reprod Biol ; 193: 27-33, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26218557

RESUMO

Endometrial injury to improve implantation for women undergoing assisted reproductive techniques has attracted a lot of attention recently and has rapidly become incorporated into clinical practice. The aim of this study is, thus, to assess the effectiveness and safety of endometrial injury performed in the cycle preceding assisted reproductive techniques in women with recurrent implantation failure. Electronic database searches, including MEDLINE, EMBASE, CENTRAL and grey literature, up to 30th May 2015 were conducted with no restrictions. Randomized controlled trials comparing endometrial injury versus placebo or no treatment in the cycle preceding assisted reproductive techniques in women with recurrent implantation failure were selected. The primary outcome was live birth rate. Secondary outcomes were clinical pregnancy, implantation, miscarriage and procedure-related complication rates. Of the 1115 publications identified, 4 met the inclusion criteria. Meta-analysis was not possible due to significant clinical heterogeneity among the included studies. Patients' characteristics differed, as did the intervention used with endometrial injury being performed at different phases of the preceding menstrual cycle. Moreover, the effect of endometrial injury on live birth and clinical pregnancy rates were inconsistent among the included studies. In summary, there is currently insufficient evidence to support the use of endometrial injury in women with recurrent implantation failure undergoing assisted reproductive techniques while the procedure-associated complication rate has not been assessed. Clinical implementation should, thus, be deferred until robust evidence becomes available.


Assuntos
Perda do Embrião/prevenção & controle , Endométrio/cirurgia , Nascido Vivo , Complicações Pós-Operatórias/epidemiologia , Aborto Espontâneo/epidemiologia , Implantação do Embrião , Transferência Embrionária , Feminino , Humanos , Gravidez , Taxa de Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Prevenção Secundária
12.
Stem Cells ; 33(3): 639-45, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25377180

RESUMO

While the fertilized egg inherits its nuclear DNA from both parents, the mitochondrial DNA is strictly maternally inherited. Cells contain multiple copies of mtDNA, each of which encodes 37 genes, which are essential for energy production by oxidative phosphorylation. Mutations can be present in all, or only in some copies of mtDNA. If present above a certain threshold, pathogenic mtDNA mutations can cause a range of debilitating and fatal diseases. Here, we provide an update of currently available options and new techniques under development to reduce the risk of transmitting mtDNA disease from mother to child. Preimplantation genetic diagnosis (PGD), a commonly used technique to detect mutations in nuclear DNA, is currently being offered to determine the mutation load of embryos produced by women who carry mtDNA mutations. The available evidence indicates that cells removed from an eight-cell embryo are predictive of the mutation load in the entire embryo, indicating that PGD provides an effective risk reduction strategy for women who produce embryos with low mutation loads. For those who do not, research is now focused on meiotic nuclear transplantation techniques to uncouple the inheritance of nuclear and mtDNA. These approaches include transplantation of any one of the products or female meiosis (meiosis II spindle, or either of the polar bodies) between oocytes, or the transplantation of pronuclei between fertilized eggs. In all cases, the transferred genetic material arises from a normal meiosis and should therefore, not be confused with cloning. The scientific progress and associated regulatory issues are discussed.


Assuntos
DNA Mitocondrial/genética , Doenças Mitocondriais/prevenção & controle , Terapia de Substituição Mitocondrial/métodos , Técnicas de Reprodução Assistida , Feminino , Humanos , Doenças Mitocondriais/genética , Gravidez
13.
Appl Biochem Biotechnol ; 174(3): 1188-200, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25024132

RESUMO

A label-free electrochemical bianalyte immunosensor has been designed for simultaneous detection of lung cancer biomarkers (anti-MAGE A2 and anti-MAGE A11) using carbon nanotubes-chitosan (CNT-CHI) composite. To achieve this, acid-functionalized single-walled CNTs were used to prepare CNT-CHI gel and electrodes were fabricated by drop casting method onto graphite surface. Lung cancer biomarkers specific antigens (Ag), i.e., MAGE A2 and MAGE A11, were covalently immobilized onto CNT-CHI/graphite electrode separately for fabrication process. Fabricated immunoelectrodes (MAGE A2/CNT-CHI/graphite and MAGE A11/CNT-CHI/graphite) were characterized at each modification step by cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Both immunoelectrodes showed successful detection of respective analytes (anti-MAGE A2 and anti-MAGE A11) from 5 fg mL(-1) to 50 ng mL(-1) using differential pulse voltammetry (DPV). Both Ag/CNT-CHI/graphite immunoelectrodes (using MAGE A2 and MAGE A11) were independently capable of distinguishing specific and nonspecific analytes like CD59, D-dimers, etc. Response studies of both immunoelectrodes revealed successful demonstration of simultaneous detection of anti-MAGE A2 and A11 independently in a single experimental run when exposed to a mixture of various analyte concentrations in different combinations irrespective of the presence of other analyte present in the same vessel.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Técnicas Biossensoriais , Quitosana/química , Neoplasias Pulmonares/diagnóstico , Proteínas de Neoplasias/isolamento & purificação , Antígenos de Neoplasias/imunologia , Grafite/química , Humanos , Neoplasias Pulmonares/imunologia , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanotubos de Carbono/química , Proteínas de Neoplasias/imunologia , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Dalton Trans ; 43(17): 6396-405, 2014 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-24604337

RESUMO

We report on a bottom up approach for the synthesis of a Pd-polypyrrole nanocomposite material. The composite material was characterized by means of different techniques, such as UV-vis, IR, and Raman spectroscopy, which offered information about the chemical structure of the polymer, whereas electron microscopy images provided information regarding the morphology of the composite material and the distribution of the metal particles in the polymer matrix. During the synthesis of the nanocomposite, the Pd nanoparticles act as a catalyst for a model proton-coupled electron transfer reaction. The Pd-polypyrrole nanocomposite material was also used as a catalyst for the electro-catalytic detection of tryptophan, a precursor for some neurotransmitters.

15.
Indian J Exp Biol ; 49(6): 469-74, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21702227

RESUMO

Helicoverpa armigera, a polyphagous lepidopteron insect pest causes severe yield loss in cotton, legumes, tomato, okra and other crops. Application of chemical pesticides although effective, has human health and environmental safety concerns. Moreover, development of resistance against most of the available pesticides is compelling to look for alternative strategies. Adoption of Bt transgenic crops have resulted in reduction in pesticide consumption and increasing crop productivity. However, sustainability of Bt transgenic crops is threatened by the emergence of insect resistance. In the present study potential insecticidal siRNA were identified in six H. armigera horrhonal pathway genes. Out of over 2000 computationally identified siRNA, 16 most promising siRNA were selected that address the biosafety concerns and have high potential of targeted gene silencing. These siRNA will be useful for chemical synthesis, in insect feeding assays and knockdown the target H. armigera hormone biosynthesis, consequently obstructing the completion of insect life cycle. The siRNA have a great potential of deployment to control H. annrmigera alone as well as with Bt for insect resistance management.


Assuntos
Controle de Insetos/métodos , Lepidópteros/genética , Lepidópteros/patogenicidade , RNA Interferente Pequeno/genética , Animais , Sequência de Bases , Inativação Gênica , Genes de Insetos , Hormônios de Inseto/genética
16.
Stem Cells ; 25(12): 3045-57, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17872502

RESUMO

Human embryonic stem cells (hESC) promise tremendous potential as a developmental and cell therapeutic tool. The combined effort of stimulatory and inhibitory signals regulating gene expression, which drives the tissue differentiation and morphogenetic processes during early embryogenesis, is still very poorly understood. With the scarcity of availability of human embryos for research, hESC can be used as an alternative source to study the early human embryogenesis. Hyaluronan (HA), a simple hydrating sugar, is present abundantly in the female reproductive tract during fertilization, embryo growth, and implantation and plays an important role in early development of the mammalian embryo. HA and its binding protein RHAMM regulate various cellular and hydrodynamic processes from cell migration, proliferation, and signaling to regulation of gene expression, cell differentiation, morphogenesis, and metastasis via both extracellular and intracellular pathways. In this study, we show for the first time that HA synthase gene HAS2 and its binding receptor RHAMM are differentially expressed during all stages of preimplantation human embryos and hESC. RHAMM expression is significantly downregulated during differentiation of hESC, in contrast to HAS2, which is significantly upregulated. Most importantly, RHAMM knockdown results in downregulation of several pluripotency markers in hESC, induction of early extraembryonic lineages, loss of cell viability, and changes in hESC cycle. These data therefore highlight an important role for RHAMM in maintenance of hESC pluripotency, viability, and cell cycle control. Interestingly, HAS2 knockdown results in suppression of hESC differentiation without affecting hESC pluripotency. This suggests an intrinsic role for HAS2 in hESC differentiation process. In accordance with this, addition of exogenous HA to the differentiation medium enhances hESC differentiation to mesodermal and cardiac lineages. Disclosure of potential conflicts of interest is found at the end of this article.


Assuntos
Blastocisto/metabolismo , Desenvolvimento Embrionário/genética , Células-Tronco Embrionárias/fisiologia , Proteínas da Matriz Extracelular/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Glucuronosiltransferase/genética , Receptores de Hialuronatos/genética , Ácido Hialurônico/fisiologia , Blastocisto/citologia , Blastocisto/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Proteínas da Matriz Extracelular/fisiologia , Glucuronosiltransferase/fisiologia , Humanos , Receptores de Hialuronatos/fisiologia , Hialuronan Sintases , Ácido Hialurônico/biossíntese , Ácido Hialurônico/genética , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/fisiologia
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