Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
1.
PLoS Pathog ; 20(5): e1012148, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728367

RESUMO

Previously, we found that Mycobacterium tuberculosis (Mtb) infection in type 2 diabetes mellitus (T2DM) mice enhances inflammatory cytokine production which drives pathological immune responses and mortality. In the current study, using a T2DM Mtb infection mice model, we determined the mechanisms that make T2DM mice alveolar macrophages (AMs) more inflammatory upon Mtb infection. Among various cell death pathways, necroptosis is a major pathway involved in inflammatory cytokine production by T2DM mice AMs. Anti-TNFR1 antibody treatment of Mtb-infected AMs from T2DM mice significantly reduced expression of receptor interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like (MLKL) (necroptosis markers) and IL-6 production. Metabolic profile comparison of Mtb-infected AMs from T2DM mice and Mtb-infected AMs of nondiabetic control mice indicated that 2-ketohexanoic acid and deoxyadenosine monophosphate were significantly abundant, and acetylcholine and pyridoxine (Vitamin B6) were significantly less abundant in T2DM mice AMs infected with Mtb. 2-Ketohexanoic acid enhanced expression of TNFR1, RIPK3, MLKL and inflammatory cytokine production in the lungs of Mtb-infected nondiabetic mice. In contrast, pyridoxine inhibited RIPK3, MLKL and enhanced expression of Caspase 3 (apoptosis marker) in the lungs of Mtb-infected T2DM mice. Our findings demonstrate that metabolic changes in Mtb-infected T2DM mice enhance TNFR1-mediated necroptosis of AMs, which leads to excess inflammation and lung pathology.


Assuntos
Diabetes Mellitus Tipo 2 , Mycobacterium tuberculosis , Necroptose , Animais , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/microbiologia , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/microbiologia , Camundongos Endogâmicos C57BL , Tuberculose/imunologia , Tuberculose/metabolismo , Tuberculose/microbiologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/microbiologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Masculino , Citocinas/metabolismo
2.
Blood ; 143(16): 1670-1675, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38427750

RESUMO

ABSTRACT: Activated protein C (APC) was shown to release extracellular vesicles (EVs). APC bound to the EVs was thought to be responsible for cytoprotection. Our study demonstrates that the cytoprotective effects of APC-released EVs are independent of APC. APC-released EVs carry anti-inflammatory microRNAs in their cargo.


Assuntos
Citoproteção , Vesículas Extracelulares , Proteína C , Comunicação Celular , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , Proteína C/metabolismo , Humanos
3.
J Immunol ; 213(5): 669-677, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39007739

RESUMO

Tissue-resident immune cells play important roles in local tissue homeostasis and infection control. There is no information on the functional role of lung-resident CD3-NK1.1+CD69+CD103+ cells in intranasal Bacillus Calmette-Guérin (BCG)-vaccinated and/or Mycobacterium tuberculosis (Mtb)-infected mice. Therefore, we phenotypically and functionally characterized these cells in mice vaccinated intranasally with BCG. We found that intranasal BCG vaccination increased CD3-NK1.1+ cells with a tissue-resident phenotype (CD69+CD103+) in the lungs during the first 7 d after BCG vaccination. Three months post-BCG vaccination, Mtb infection induced the expansion of CD3-NK1.1+CD69+CD103+ (lung-resident) cells in the lung. Adoptive transfer of lung-resident CD3-NK1.1+CD69+CD103+ cells from the lungs of BCG-vaccinated mice to Mtb-infected naive mice resulted in a lower bacterial burden and reduced inflammation in the lungs. Our findings demonstrated that intranasal BCG vaccination induces the expansion of CD3-NK1.1+CD69+CD103+ (lung-resident) cells to provide protection against Mtb infection.


Assuntos
Antígenos CD , Vacina BCG , Cadeias alfa de Integrinas , Pulmão , Mycobacterium tuberculosis , Animais , Vacina BCG/imunologia , Camundongos , Pulmão/imunologia , Mycobacterium tuberculosis/imunologia , Antígenos CD/imunologia , Cadeias alfa de Integrinas/imunologia , Camundongos Endogâmicos C57BL , Complexo CD3/imunologia , Lectinas Tipo C/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Feminino , Vacinação , Transferência Adotiva , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/prevenção & controle , Antígenos de Diferenciação de Linfócitos T
4.
Reprod Biomed Online ; 49(3): 104105, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38986195

RESUMO

RESEARCH QUESTION: Do the various forms of hormonal and non-hormonal contraceptives have any association with ovarian stimulation outcomes, such as oocyte yield and maturation, in patients undergoing planned oocyte cryopreservation (POC)? DESIGN: This retrospective cohort study included all patients who underwent POC cycles between 2011 and 2023. The use of types of contraception before a POC cycle was recorded. The study evaluated the median number of cumulus-oocyte complexes obtained after vaginal oocyte retrieval and the proportion of metaphase II oocytes that underwent vitrification among all the cohorts. RESULTS: A total of 4059 oocyte freezing cycles were included in the analysis. Eight types of contraceptive method were recognized in patients undergoing ovarian stimulation: intrauterine device (IUD), copper (n = 84); IUD, levonorgestrel low dose (<52 mg) (n = 37); IUD, levonorgestrel (n = 192); subdermal etonogestrel implant (n = 14); injectable medroxyprogesterone acetate (n = 11); etonogestrel vaginal ring (n = 142); combined oral contraceptive pills (n = 2349); and norelgestromin transdermal patch (n = 10). The control group included patients not using contraceptives or using barrier or calendar methods (n = 1220). Among all the cohorts the median number of cumulus-oocyte complexes retrieved during oocyte retrieval was comparable (P = 0.054), and a significant difference in oocyte maturity rate with median number of vitrified oocytes was found (P = 0.03, P < 0.001, respectively). After adjusting for confounders a multivariate analysis found no association between the type of contraceptive and proportion of metaphase II oocytes available for cryopreservation. CONCLUSIONS: Among the various forms of contraception, none was shown to have an adverse association with oocyte yield or maturation rate in patients undergoing POC.


Assuntos
Criopreservação , Recuperação de Oócitos , Oócitos , Humanos , Feminino , Estudos Retrospectivos , Adulto , Oócitos/efeitos dos fármacos , Indução da Ovulação/métodos , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/farmacologia , Preservação da Fertilidade/métodos
5.
Am J Gastroenterol ; 118(12): 2184-2190, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36940434

RESUMO

INTRODUCTION: There is a need for evidence-based counseling for women with chronic liver disease (LD) who may experience impaired fertility. Currently, the literature on assisted reproductive technology (ART) treatment in women with LD has been limited to a single European case series. We evaluated ART treatment outcomes in patients with LD and compared with controls. METHODS: The retrospective study evaluated women with and without LD who had normal ovarian reserve and underwent ART treatment in a high-volume fertility practice from 2002 to 2021. RESULTS: We identified 295 women with LD (mean age 37.8 ± 5.2 years) who underwent 1,033 ART treatment cycles; of these women, 115 underwent 186 in vitro fertilization (IVF) cycles. Six women (2.0%) had cirrhosis, 8 (2.7%) were postliver transplantation, and 281 (95.3%) had chronic LD, with viral hepatitis (B and C) being the most prevalent. In the subgroup who underwent IVF and embryo biopsy, the median fibrosis-4 score was 0.81 (0.58-1.03), and there were no statistically significant differences in response to controlled ovarian stimulation, embryo fertilization rate, or ploidy outcome in patients with LD compared with controls. In those who subsequently underwent a single thawed euploid embryo transfer to achieve pregnancy, there were no statistically significant differences in rates of clinical pregnancy, clinical pregnancy loss, or live birth in patients with LD compared with controls. DISCUSSION: To the best of our knowledge, this study is the largest to date to evaluate IVF efficacy in women with LD. Our study demonstrates that patients with LD have similar ART treatment outcomes compared with those without LD.


Assuntos
Doenças do Sistema Digestório , Hepatopatias , Gravidez , Humanos , Feminino , Adulto , Estudos Retrospectivos , Técnicas de Reprodução Assistida , Fertilização in vitro , Nascido Vivo , Hepatopatias/terapia , Resultado do Tratamento , Taxa de Gravidez
6.
Hum Reprod ; 38(6): 1151-1161, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37075318

RESUMO

STUDY QUESTION: Do infertile couples who recently utilized clomiphene citrate (CC) for ovulation induction or ovarian stimulation (<90 days previously) followed by a single euploid embryo transfer (SEET) have lower implantation potential compared with patients who were not exposed to CC within 90 days before embryo transfer (ET)? SUMMARY ANSWER: There does not appear to be an association between recent CC exposure and lower implantation potential in patients who undergo a frozen embryo transfer (FET) of euploid embryos. WHAT IS KNOWN ALREADY: Clomiphene has been found to be associated with lower pregnancy rates when compared against other ovarian stimulation medications. The majority of published research about the effects of CC on implantation potential suggest an anti-estrogenic effect on the endometrium. Quality evidence and information about utilization of CC and its effect on implantation potential after euploid ETs is lacking in the literature. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study with propensity score matching was carried out. We included all patients that underwent an autologous SEET from September 2016 to September 2022 at a single academic-private ART center. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study group included patients that had utilized CC during either ovulation induction cycles and/or controlled ovarian stimulation at least 90 days before FET. A propensity score-matched control group of patients that were unexposed to CC within 90 days prior to SEET was used for comparisons. The primary outcome was positive pregnancy test (defined as a positive serum ß-hCG measured 9 days after ET), with other outcomes including clinical pregnancy, ongoing pregnancy, biochemical pregnancy loss, and clinical pregnancy loss rates per SEET. Multivariate regression analyses fitted with generalized estimating equations were utilized to analyze if there was an association between CC utilization and IVF outcomes. Furthermore, the study evaluated the cumulative effect of CC and endometrial receptivity in vivo and subsequent IVF outcomes. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 593 patients with utilization of CC in <90 days before ET were compared with 1779 matched controls. Positive pregnancy test rates were comparable among the control group and the CC exposed groups, respectively (74.3% versus 75.7%, P = 0.79), as were clinical pregnancy (64.0% versus 65.0%, P = 0.60), ongoing pregnancy (51.8% versus 53.2%, P = 0.74), biochemical pregnancy loss (15.7% versus 14.03%, P = 0.45), and clinical pregnancy loss rates were also comparable among cohorts (17.1% versus 18.1%, P = 0.71). No association was found between utilization of clomiphene and lower implantation rates (adjusted odds ratio 0.95, 95% CI 0.76-1.18). Also, no differences were observed in sub-analyses based on multiple CC utilization periods. Finally, no association was found between the number of consecutive cumulative clomiphene cycles and sub-optimal IVF outcomes. LIMITATIONS, REASONS FOR CAUTION: The study has inherent bias that originated from its retrospective design. Serum levels of CC were not measured and sample size for the sub-analyses was small. WIDER IMPLICATIONS OF THE FINDINGS: There does not appear to be an association between recent CC exposure and lower implantation potential in patients who undergo a FET of euploid embryos. This finding remains consistent, even in patients who undergo multiple, consecutive clomiphene cycles prior to ET. There were no long-term effects of CC on endometrial development and clinical characteristics examined in this study. Patients that utilized CC medication prior to a SEET cycle for either ovarian stimulation or ovulation induction, can be assured that there is no evidence of a residual effect of recent CC administration that could jeopardize their pregnancy probability. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for the realization of this study. A.C. is advisor and/or board member of Sema4 (stakeholder in data) and Progyny. The other authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Aborto Espontâneo , Transferência Embrionária , Feminino , Gravidez , Humanos , Estudos Retrospectivos , Transferência Embrionária/métodos , Clomifeno/uso terapêutico , Taxa de Gravidez , Transferência de Embrião Único/métodos , Indução da Ovulação/métodos , Fertilização in vitro/métodos
7.
Int J Mol Sci ; 24(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37108430

RESUMO

Mycobacterium tuberculosis (Mtb) has latently infected over two billion people worldwide (LTBI) and caused ~1.6 million deaths in 2021. Human immunodeficiency virus (HIV) co-infection with Mtb will affect the Mtb progression and increase the risk of developing active tuberculosis by 10-20 times compared with HIV- LTBI+ patients. It is crucial to understand how HIV can dysregulate immune responses in LTBI+ individuals. Plasma samples collected from healthy and HIV-infected individuals were investigated using liquid chromatography-mass spectrometry (LC-MS), and the metabolic data were analyzed using the online platform Metabo-Analyst. ELISA, surface and intracellular staining, flow cytometry, and quantitative reverse-transcription PCR (qRT-PCR) were performed using standard procedures to determine the surface markers, cytokines, and other signaling molecule expressions. Seahorse extra-cellular flux assays were used to measure mitochondrial oxidative phosphorylation and glycolysis. Six metabolites were significantly less abundant, and two were significantly higher in abundance in HIV+ individuals compared with healthy donors. One of the HIV-upregulated metabolites, N-acetyl-L-alanine (ALA), inhibits pro-inflammatory cytokine IFN-γ production by the NK cells of LTBI+ individuals. ALA inhibits the glycolysis of LTBI+ individuals' NK cells in response to Mtb. Our findings demonstrate that HIV infection enhances plasma ALA levels to inhibit NK-cell-mediated immune responses to Mtb infection, offering a new understanding of the HIV-Mtb interaction and providing insights into the implication of nutrition intervention and therapy for HIV-Mtb co-infected patients.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Humanos , Células Matadoras Naturais
8.
J Assist Reprod Genet ; 39(9): 2051-2059, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35751829

RESUMO

OBJECTIVE: To analyze the correlation between TE grading and initial ß-hCG serum level after single euploid embryo transfer. Secondarily, to explore the association between TE grading with subsequent IVF outcomes. DESIGN: Retrospective cohort analysis. SETTING: Single, academic, private infertility and assisted reproductive care institute. PATIENTS OR OTHER PARTICIPANTS: Infertility patients who underwent a single euploid embryo transfer that resulted in a positive pregnancy test. INTERVENTION(S): ß-hCG measurements. MAIN OUTCOME MEASURE(S): Correlation between TE grade with first ß-hCG measurement. Second outcome measurements included ongoing pregnancy, biochemical pregnancy loss, and clinical pregnancy loss rates. RESULTS: 2,798 cases were analyzed. A significant difference in initial ß-hCG measurement among groups (TE A: median 143.4 mIU/mL IQR 79.2-211.2; TE B: 119 mIU/mL IQR 57.1-177.8; TE C: 82.4 mIU/mL IQR 36.3-136.4, p ≤ 0.0001) was observed. There was a significant correlation found between the TE grade and ß-hCG measurements (p ≤ 0.0001, r2 = 0.10). TE grade was not associated with higher odds of biochemical pregnancy loss (TE A vs. TE B: aOR 1.01 CI95% 0.97-1.05; TE A vs. TE C: aOR 1.03 CI95% 0.98-1.08), or higher odds of clinical pregnancy loss (TE A vs. TE B: aOR 1.02 CI95% 0.98-1.05; TE A vs. TE C: aOR 1.03 CI95% 0.98-1.07). CONCLUSIONS: In patients with euploid embryos, TE grade correlates with the first pregnancy test measurement of ß-hCG. We propose this finding helps to appoint a relevant link between morphology assessment and early embryo development in vivo.


Assuntos
Aborto Espontâneo , Infertilidade , Blastocisto , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/métodos , Humanos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
9.
Hum Reprod ; 35(8): 1889-1899, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32649755

RESUMO

STUDY QUESTION: What is the impact of a late follicular phase progesterone elevation (LFPE) during controlled ovarian hyperstimulation (COH) on embryonic competence and reproductive potential in thaw cycles of preimplantation genetic testing for aneuploidy (PGT-A) screened embryos? SUMMARY ANSWER: Our study findings suggest that LFPE, utilizing a progesterone cutoff value of 2.0 ng/ml, is neither associated with impaired embryonic development, increased rate of embryonic aneuploidy, nor compromised implantation and pregnancy outcomes following a euploid frozen embryo transfer (FET) cycle. WHAT IS KNOWN ALREADY: Premature progesterone elevation during COH has been associated with lower pregnancy rates due to altered endometrial receptivity in fresh IVF cycles. Also, increased levels of progesterone (P) have been suggested to be a marker for ovarian dysfunction, with some evidence to show an association between LFPE and suboptimal embryonic development. However, the effect of LFPE on embryonic competence is still controversial. STUDY DESIGN, SIZE, DURATION: Retrospective cohort analysis in a single, academic ART center from September 2016 to March 2020. In total, 5244 COH cycles for IVF/PGT-A were analyzed, of those 5141 were included in the analysis. A total of 23 991 blastocysts underwent trophectoderm biopsy and PGT analysis. Additionally, the clinical IVF outcomes of 5806 single euploid FET cycles were evaluated. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cohorts were separated in two groups: Group 1: oocytes retrieved from cycles with normal P levels during ovulation trigger (P ≤ 2.0 ng/ml); Group 2: oocytes retrieved after cycles in which LFPE was noted (P > 2.0 ng/ml). Extended culture and PGT-A was performed. Secondly, IVF outcomes after a single euploid FET were evaluated for each cohort. MAIN RESULTS AND THE ROLE OF CHANCE: Four thousand nine hundred and twenty-five cycles in Group 1 were compared with 216 cycles on Group 2. Oocyte maturity rates, fertilization rates and blastulation rates were comparable among groups. A 65.3% (n = 22 654) rate of utilizable blastocysts was found in patients with normal P levels and were comparable to the 62.4% (n = 1337) observed in those with LFPE (P = 0.19). The euploidy rates were 52.8% (n = 11 964) and 53.4% (n = 714), respectively, albeit this difference was not statistically significant (P = 0.81). Our multivariate analysis was fitted with a generalized estimating equation (GEE) and no association was found with LFPE and an increased odds of embryo aneuploidy (adjusted odds ratio 1.04 95% CI 0.86-1.27, P = 0.62). A sub-analysis of subsequent 5806 euploid FET cycles (normal P: n = 5617 cycles and elevated P: n = 189 cycles) showed no differences among groups in patient's BMI, Anti-Müllerian hormone (AMH), endometrial thickness at FET and number of prior IVF cycles. However, a significant difference was found in patient's age and oocyte age. The number of good quality embryos transferred, implantation rate, clinical pregnancy rate, ongoing pregnancy rate, multiple pregnancy rate and clinical pregnancy loss rates were comparable among groups. Of the registered live births (normal P group: n = 2198; elevated P group: n = 52), there were no significant differences in gestational age weeks (39.0 ± 1.89 versus 39.24 ± 1.53, P = 0.25) and birth weight (3317 ± 571.9 versus 3 266 ± 455.8 g, P = 0.26) at delivery, respectively. LIMITATIONS, REASONS FOR CAUTION: The retrospective nature of the study and probable variability in the study center's laboratory protocol(s), selected progesterone cutoff value and progesterone assay techniques compared to other ART centers may limit the external validity of our findings. WIDER IMPLICATIONS OF THE FINDINGS: Based on robust sequencing data from a large cohort of embryos, we conclude that premature P elevation during IVF stimulation does not predict embryonic competence. Our study results show that LFPE is neither associated with impaired embryonic development nor increased rates of aneuploidy. Embryos obtained from cycles with LFPE can be selected for transfer, and patients can be reassured that the odds of achieving a healthy pregnancy are similar to the embryos exposed during COH cycles to physiologically normal P levels. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for the realization of this study. Dr A.B.C. is advisor and/or board member of Sema 4 (Stakeholder in data), Progyny and Celmatix. The other authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: NA.


Assuntos
Fase Folicular , Progesterona , Implantação do Embrião , Feminino , Fertilização in vitro , Humanos , Indução da Ovulação , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
10.
Biophys J ; 116(8): 1527-1537, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30975454

RESUMO

Chemotaxis, together with motility, helps bacteria foraging in their habitat. Motile bacteria exhibit a variety of motility patterns, often controlled by chemotaxis, to promote dispersal. Motility in many bacteria is powered by a bidirectional flagellar motor. The flagellar motor has been known to briefly pause during rotation because of incomplete reversals or stator detachment. Transient pauses were previously observed in bacterial strains lacking CheY, and these events could not be explained by incomplete motor reversals or stator detachment. Here, we systematically analyzed swimming trajectories of various chemotaxis mutants of the monotrichous soil bacterium, Azospirillum brasilense. Like other polar flagellated bacterium, the main swimming pattern in A. brasilense is run and reverse. A. brasilense also uses run-pauses and putative run-reverse-flick-like swimming patterns, although these are rare events. A. brasilense mutant derivatives lacking the chemotaxis master histidine kinase, CheA4, or the central response regulator, CheY7, also showed transient pauses. Strikingly, the frequency of transient pauses increased dramatically in the absence of CheY4. Our findings collectively suggest that reversals and pauses are controlled through signaling by distinct CheY homologs, and thus are likely to be functionally important in the lifestyle of this soil organism.


Assuntos
Azospirillum brasilense/citologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Quimiotaxia , Homologia de Sequência de Aminoácidos , Sequência de Aminoácidos , Azospirillum brasilense/metabolismo , Rotação , Natação
11.
J Bacteriol ; 198(12): 1764-1772, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27068592

RESUMO

UNLABELLED: The genomes of most motile bacteria encode two or more chemotaxis (Che) systems, but their functions have been characterized in only a few model systems. Azospirillum brasilense is a motile soil alphaproteobacterium able to colonize the rhizosphere of cereals. In response to an attractant, motile A. brasilense cells transiently increase swimming speed and suppress reversals. The Che1 chemotaxis pathway was previously shown to regulate changes in the swimming speed, but it has a minor role in chemotaxis and root surface colonization. Here, we show that a second chemotaxis system, named Che4, regulates the probability of swimming reversals and is the major signaling pathway for chemotaxis and wheat root surface colonization. Experimental evidence indicates that Che1 and Che4 are functionally linked to coordinate changes in the swimming motility pattern in response to attractants. The effect of Che1 on swimming speed is shown to enhance the aerotactic response of A. brasilense in gradients, likely providing the cells with a competitive advantage in the rhizosphere. Together, the results illustrate a novel mechanism by which motile bacteria utilize two chemotaxis pathways regulating distinct motility parameters to alter movement in gradients and enhance the chemotactic advantage. IMPORTANCE: Chemotaxis provides motile bacteria with a competitive advantage in the colonization of diverse niches and is a function enriched in rhizosphere bacterial communities, with most species possessing at least two chemotaxis systems. Here, we identify the mechanism by which cells may derive a significant chemotactic advantage using two chemotaxis pathways that ultimately regulate distinct motility parameters.


Assuntos
Azospirillum brasilense/fisiologia , Quimiotaxia , Transdução de Sinais , Azospirillum brasilense/citologia , Azospirillum brasilense/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Raízes de Plantas/microbiologia , Triticum/microbiologia
12.
J Reprod Med ; 61(9-10): 425-430, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30383939

RESUMO

OBJECTIVE: To evaluate outcomes of patients with unexplained infertility who underwent letrozole (LET)- stimulated controlled ovarian stimulation (COS) with timed sexual intercourse (IC) as compared to patients treated with clomiphene citrate (CC) and intrauterine insemination (IUI). STUDY DESIGN: A non- randomized, retrospective study where unexplained in- fertility patients (n=7,764). underwent a COS cycle with both LET and timed IC or with CC and IUI from January 2010-June 2014. One group consisted of patients who completed a COS cycle with LET and were instructed to have sexual IC. The other included patients were treated with CC and underwent IUI. Pregnancy rates (PRs) were compared between groups. RESULTS: No statistical difference was observed in each group's age or serum follicule-stimulating hor- mone levels. A statistical significance in LET versus CC-stimulated groups was observed for mean endome- trial thickness (8.3 ± 1.7 vs. 7.9 ± 1.8 mm) and follicular response (2.0 ± 1.0 vs. 2.3 ± 1.3), respectively. Clinical PRs after timed IC were significantly higher in the LET versus CC-stimulated group (15.0% vs 11.8%). Clinical PRs after timed IUI were also significantly higher in the LET versus CC-stimulated group (12.3% vs. 11.5%). Moreover, clinical PRs in LET with IC were significant- ly higher than CC with IUI (15.0% vs. 11.5%). CONCLUSION: Unexplained infertility patients who underwent LET stimulation with IC werefound to have better pregnancy out- comes as compared to those who underwent timed IC.or IUI with CC stimulation.


Assuntos
Clomifeno/uso terapêutico , Coito , Fármacos para a Fertilidade Feminina/uso terapêutico , Inseminação Artificial , Letrozol/uso terapêutico , Adulto , Endométrio/diagnóstico por imagem , Feminino , Humanos , Infertilidade Feminina/terapia , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Ultrassonografia
13.
J Assist Reprod Genet ; 33(3): 401-412, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26768140

RESUMO

PURPOSE: The aim of this study is to compare implantation and live birth rates (LBR) between fresh euploid embryo transfers versus cryo-all cycles with a subsequent embryo transfer into a prepared endometrium. MATERIAL AND METHODS: This is a retrospective cohort study. Patients who underwent an IVF cycle with PGS with trophectoderm biopsy from January 2011 to July 2015 were included. Patients were divided into three groups: "Fresh Only," "Frozen Embryo Transfer ('FET) Only," and "Fresh ET then FET." For "Fresh Only" group (n = 345), PGS results were received within 24 h. For "FET Only" group (n = 514), results were expected after 24 h, and embryos were cryopreserved after biopsy; only FET was performed in this group (no fresh transfer). For "FET with a previous fresh ET" (n = 139) group, patients underwent a fresh ET with a subsequent FET, in which the same cohort of embryos was utilized. The main outcome measures were pregnancy rate (PR), clinical PR, implantation rate (IR), LBR, and early pregnancy loss rate. RESULTS: IRs were statistically higher in the "FET Only" group when compared to the "Fresh Only" group (59.5 vs. 50.6%, p < 0.01) and the "FET with a previous fresh ET" (59.5 vs. 50.6%, p < 0.05). LBR was statistically significant in the "FET Only" group when compared to the "Fresh Only" group (57.6 vs. 46.5 %, p < 0.005) but not when compared to "FET with a previous fresh ET" group (57.6 vs. 47.7%, p = 0.07). CONCLUSIONS: This analysis suggests euploid embryos to be more likely to implant and achieve a LBR in a synthetic FET cycle than in a fresh cycle.


Assuntos
Blastocisto/fisiologia , Criopreservação/métodos , Transferência Embrionária/métodos , Endométrio/fisiologia , Diagnóstico Pré-Implantação/métodos , Adulto , Aneuploidia , Estudos de Coortes , Implantação do Embrião/genética , Feminino , Fertilização in vitro , Humanos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento
14.
Appl Environ Microbiol ; 81(24): 8346-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26407887

RESUMO

The ability of bacteria to monitor their metabolism and adjust their behavior accordingly is critical to maintain competitiveness in the environment. The motile microaerophilic bacterium Azospirillum brasilense navigates oxygen gradients by aerotaxis in order to locate low oxygen concentrations that can support metabolism. When cells are exposed to elevated levels of oxygen in their surroundings, motile A. brasilense cells implement an alternative response to aerotaxis and form transient clumps by cell-to-cell interactions. Clumping was suggested to represent a behavior protecting motile cells from transiently elevated levels of aeration. Using the proteomics of wild-type and mutant strains affected in the extent of their clumping abilities, we show that cell-to-cell clumping represents a metabolic scavenging strategy that likely prepares the cells for further metabolic stresses. Analysis of mutants affected in carbon or nitrogen metabolism confirmed this assumption. The metabolic changes experienced as clumping progresses prime cells for flocculation, a morphological and metabolic shift of cells triggered under elevated-aeration conditions and nitrogen limitation. The analysis of various mutants during clumping and flocculation characterized an ordered set of changes in cell envelope properties accompanying the metabolic changes. These data also identify clumping and early flocculation to be behaviors compatible with the expression of nitrogen fixation genes, despite the elevated-aeration conditions. Cell-to-cell clumping may thus license diazotrophy to microaerophilic A. brasilense cells under elevated oxygen conditions and prime them for long-term survival via flocculation if metabolic stress persists.


Assuntos
Adaptação Fisiológica/fisiologia , Azospirillum brasilense/metabolismo , Aderência Bacteriana/fisiologia , Oxigênio/metabolismo , Estresse Fisiológico/fisiologia , Azospirillum brasilense/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Cromatografia Líquida , Elementos de DNA Transponíveis/genética , Floculação , Reação em Cadeia da Polimerase , Espectrometria de Massas em Tandem
15.
Reprod Biol Endocrinol ; 13: 91, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26272081

RESUMO

BACKGROUND: Elevated follicle stimulating hormone (FSH) is associated with poor vaginal oocyte retrieval (VOR) outcomes and cycle cancellations but intercycle variability in basal FSH reportedly does not predict ovarian response. METHODS: We conducted a retrospective cohort study of basal FSH (n = 15573 cycles) in couples (n = 9132) who initiated IVF cycle(s) with basal estradiol (E2) <100 pg/mL between 2002 and 2014 to reevaluate this hypothesis. The most recent (current) FSH, maximum FSH (Max FSH) and prior cycle maximum basal FSH (PMax FSH) were computed for each cycle. Metaphase II (MII) oocyte counts were modeled by age, stimulation type, prior peak E2 level, prior MII count, Max FSH, PMax FSH and current FSH. Antral follicle counts, pregnancy, clinical pregnancy and live birth rates were modeled as secondary outcomes. RESULTS: Max FSH level distinguished completed cycles from cancelled cycles better than PMax FSH or current FSH (AUC of 0.72, 0.71 and 0.61, respectively, p < 0.001). Fewer MIIs were retrieved (5.7 ± 3.8) in cycles with Max FSH >13 mIU/mL (n = 1475) than those with ≤13 mIU/mL (n = 11978) (11.6 ± 7.1) (p < 0.001). Max FSH was a better predictor of MII count than PMax FSH or current FSH after controlling for age, stimulation type, prior peak E2 level and prior MII count. Additional MIIs were retrieved on average in cycles with PMax FSH >13 mIU/mL (n = 1930) whose current FSH was ≤13 mIU/ml rather than >13 mIU/ml (p < 0.01) after controlling for age, cycle number and stimulation type. However, no improvement in pregnancy or live birth rate was detected. CONCLUSIONS: Max FSH is the best FSH-based predictor of ovarian reserve. Retrieval benefits from waiting for a "better" month appear to exist but are limited.


Assuntos
Hormônio Foliculoestimulante/sangue , Reserva Ovariana/fisiologia , Indução da Ovulação/métodos , Taxa de Gravidez , Reprodução/fisiologia , Adulto , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Recuperação de Oócitos/métodos , Recuperação de Oócitos/tendências , Indução da Ovulação/tendências , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez/tendências , Estudos Retrospectivos , Fatores de Tempo
16.
Indian J Microbiol ; 55(2): 140-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25805900

RESUMO

Diversity analysis of Clostridium botulinum strains is complicated by high microheterogeneity caused by the presence of 9-22 copies of rrs (16S rRNA gene). The need is to mine genetic markers to identify very closely related strains. Multiple alignments of the nucleotide sequences of the 212 rrs of 13 C. botulinum strains revealed intra- and inter-genomic heterogeneity. Low intragenomic heterogeneity in rrs was evident in strains 230613, Alaska E43, Okra, Eklund 17B, Langeland, 657, Kyoto, BKT015925, and Loch Maree. The most heterogenous rrs sequences were those of C. botulinum strains ATCC 19397, Hall, H04402065, and ATCC 3502. In silico restriction mapping of these rrs sequences was observable with 137 type II Restriction endonucleases (REs). Nucleotide changes (NC) at these RE sites resulted in appearance of distinct and additional sites, and loss in certain others. De novo appearances of RE sites due to NC were recorded at different positions in rrs gene. A nucleotide transition A>G in rrs of C. botulinum Loch Maree and 657 resulted in the generation of 4 and 10 distinct RE sites, respectively. Transitions A>G, G>A, and T>C led to the loss of RE sites. A perusal of the entire NC and in silico RE mapping of rrs of C. botulinum strains provided insights into their evolution. Segregation of strains on the basis of RE digestion patterns of rrs was validated by the cladistic analysis involving six house keeping genes: dnaN, gyrB, metG, prfA, pyrG, and Rho.

17.
Cancers (Basel) ; 16(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38672649

RESUMO

Blood coagulation and cancer are intrinsically connected, hypercoagulation-associated thrombotic complications are commonly observed in certain types of cancer, often leading to decreased survival in cancer patients. Apart from the common role in coagulation, coagulation proteases often trigger intracellular signaling in various cancers via the activation of a G protein-coupled receptor superfamily protease: protease-activated receptors (PARs). Although the role of PARs is well-established in the development and progression of certain types of cancer, their impact on cancer immune response is only just emerging. The present review highlights how coagulation protease-driven PAR signaling plays a key role in modulating innate and adaptive immune responses. This is followed by a detailed discussion on the contribution of coagulation protease-induced signaling in cancer immune evasion, thereby supporting the growth and development of certain tumors. A special section of the review demonstrates the role of coagulation proteases, thrombin, factor VIIa, and factor Xa in cancer immune evasion. Targeting coagulation protease-induced signaling might be a potential therapeutic strategy to boost the immune surveillance mechanism of a host fighting against cancer, thereby augmenting the clinical consequences of targeted immunotherapeutic regimens.

18.
Cell Signal ; 121: 111263, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38897529

RESUMO

Intercellular communication, an essential biological process in multicellular organisms, is mediated by direct cell-to-cell contact and cell secretary molecules. Emerging evidence identifies a third mechanism of intercellular communication- the release of extracellular vesicles (EVs). EVs are membrane-enclosed nanosized bodies, released from cells into the extracellular environment, often found in all biofluids. The growing body of research indicates that EVs carry bioactive molecules in the form of proteins, DNA, RNAs, microRNAs (miRNAs), lipids, metabolites, etc., and upon transferring them, alter the phenotypes of the target recipient cells. Interestingly, the abundance of EVs is found to be significantly higher in different diseased conditions, most importantly cancer. In the past few decades, numerous studies have identified EV miRNAs as an important contributor in the pathogenesis of different types of cancer. However, the underlying mechanism behind EV miRNA-associated cancer progression and how it could be used as a targeted therapy remain ill-defined. The present review highlights how EV miRNAs influence essential processes in cancer, such as growth, proliferation, metastasis, angiogenesis, apoptosis, stemness, immune evasion, resistance to therapy, etc. A special emphasis has been given to the potential role of EV miRNAs as cancer biomarkers. The final section of the review delineates the ongoing clinical trials on the role of miRNAs in the progression of different types of cancer. Targeting EV miRNAs could be a potential therapeutic means in the treatment of different forms of cancer alongside conventional therapeutic approaches.


Assuntos
Vesículas Extracelulares , MicroRNAs , Neoplasias , Humanos , Vesículas Extracelulares/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/genética , MicroRNAs/metabolismo , MicroRNAs/genética , Progressão da Doença , Animais , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética
19.
Med Image Anal ; 94: 103107, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38401269

RESUMO

We propose a novel semi-supervised learning method to leverage unlabeled data alongside minimal annotated data and improve medical imaging classification performance in realistic scenarios with limited labeling budgets to afford data annotations. Our method introduces distance correlation to minimize correlations between feature representations from different views of the same image encoded with non-coupled deep neural networks architectures. In addition, it incorporates a data-driven graph-attention based regularization strategy to model affinities among images within the unlabeled data by exploiting their inherent relational information in the feature space. We conduct extensive experiments on four medical imaging benchmark data sets involving X-ray, dermoscopic, magnetic resonance, and computer tomography imaging on single and multi-label medical imaging classification scenarios. Our experiments demonstrate the effectiveness of our method in achieving very competitive performance and outperforming several state-of-the-art semi-supervised learning methods. Furthermore, they confirm the suitability of distance correlation as a versatile dependence measure and the benefits of the proposed graph-attention based regularization for semi-supervised learning in medical imaging analysis.


Assuntos
Benchmarking , Redes Neurais de Computação , Humanos , Aprendizado de Máquina Supervisionado
20.
Front Oncol ; 14: 1477610, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39391238

RESUMO

Gynecological cancer, the most common form of cancers in women worldwide, initiates in the reproductive organs of females. More often, the common treatment measures, i.e. surgery, radiation, and medical oncology are found to be unsuccessful in the treatment of gynecological tumors. Emerging evidence indicates that extracellular vesicles (EVs) play a significant role in the pathogenesis of gynecological cancers by distinct mechanisms. The present review highlights how EVs contribute to the progression of different types of gynecological cancers such as cervical cancer, endometrial cancer, ovarian cancer, vaginal cancer, uterine sarcoma, gestational trophoblastic disease (GTD), and vulvar cancer. The primary focus is to understand how EVs' cargo alters the phenotypic response of the recipient cells, thereby contributing to the progression of the disease, thus can be considered as a prognostic and diagnostic biomarker. A brief discussion on the role of EVs in the diagnosis and prognosis of different gynecological cancer types is also highlighted. Targeting the biogenesis of the EVs, their inside cargo, and EVs uptake by the recipient cells could be a potential therapeutic approach in the treatment of gynecological cancer beside conventional therapeutic means.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA