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1.
Genes Dev ; 37(19-20): 901-912, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37914351

RESUMO

Fertilization in mammals is accompanied by an intense period of chromatin remodeling and major changes in nuclear organization. How the earliest events in embryogenesis, including zygotic genome activation (ZGA) during maternal-to-zygotic transition, influence such remodeling remains unknown. Here, we have investigated the establishment of nuclear architecture, focusing on the remodeling of lamina-associated domains (LADs) during this transition. We report that LADs reorganize gradually in two-cell embryos and that blocking ZGA leads to major changes in nuclear organization, including altered chromatin and genomic features of LADs and redistribution of H3K4me3 toward the nuclear lamina. Our data indicate that the rearrangement of LADs is an integral component of the maternal-to-zygotic transition and that transcription contributes to shaping nuclear organization at the beginning of mammalian development.


Assuntos
RNA Polimerase II , Transcrição Gênica , Animais , Camundongos , RNA Polimerase II/genética , Desenvolvimento Embrionário/genética , Zigoto , Mamíferos/genética , Regulação da Expressão Gênica no Desenvolvimento , Cromatina
2.
Nature ; 625(7994): 401-409, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123678

RESUMO

DNA replication enables genetic inheritance across the kingdoms of life. Replication occurs with a defined temporal order known as the replication timing (RT) programme, leading to organization of the genome into early- or late-replicating regions. RT is cell-type specific, is tightly linked to the three-dimensional nuclear organization of the genome1,2 and is considered an epigenetic fingerprint3. In spite of its importance in maintaining the epigenome4, the developmental regulation of RT in mammals in vivo has not been explored. Here, using single-cell Repli-seq5, we generated genome-wide RT maps of mouse embryos from the zygote to the blastocyst stage. Our data show that RT is initially not well defined but becomes defined progressively from the 4-cell stage, coinciding with strengthening of the A and B compartments. We show that transcription contributes to the precision of the RT programme and that the difference in RT between the A and B compartments depends on RNA polymerase II at zygotic genome activation. Our data indicate that the establishment of nuclear organization precedes the acquisition of defined RT features and primes the partitioning of the genome into early- and late-replicating domains. Our work sheds light on the establishment of the epigenome at the beginning of mammalian development and reveals the organizing principles of genome organization.


Assuntos
Período de Replicação do DNA , Embrião de Mamíferos , Genoma , Animais , Camundongos , Blastocisto/citologia , Blastocisto/metabolismo , Cromatina/genética , Epigenoma/genética , Genoma/genética , RNA Polimerase II/metabolismo , Zigoto/citologia , Zigoto/crescimento & desenvolvimento , Zigoto/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo
3.
N Engl J Med ; 388(15): 1365-1375, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37043652

RESUMO

BACKGROUND: Prophylactic use of tranexamic acid at the time of cesarean delivery has been shown to decrease the calculated blood loss, but the effect on the need for blood transfusions is unclear. METHODS: We randomly assigned patients undergoing cesarean delivery at 31 U.S. hospitals to receive either tranexamic acid or placebo after umbilical-cord clamping. The primary outcome was a composite of maternal death or blood transfusion by hospital discharge or 7 days post partum, whichever came first. Key secondary outcomes were estimated intraoperative blood loss of more than 1 liter (prespecified as a major secondary outcome), interventions for bleeding and related complications, the preoperative-to-postoperative change in the hemoglobin level, and postpartum infectious complications. Adverse events were assessed. RESULTS: A total of 11,000 participants underwent randomization (5529 to the tranexamic acid group and 5471 to the placebo group); scheduled cesarean delivery accounted for 50.1% and 49.2% of the deliveries in the respective groups. A primary-outcome event occurred in 201 of 5525 participants (3.6%) in the tranexamic acid group and in 233 of 5470 (4.3%) in the placebo group (adjusted relative risk, 0.89; 95.26% confidence interval [CI], 0.74 to 1.07; P = 0.19). Estimated intraoperative blood loss of more than 1 liter occurred in 7.3% of the participants in the tranexamic acid group and in 8.0% of those in the placebo group (relative risk, 0.91; 95% CI, 0.79 to 1.05). Interventions for bleeding complications occurred in 16.1% of the participants in the tranexamic acid group and in 18.0% of those in the placebo group (relative risk, 0.90; 95% CI, 0.82 to 0.97); the change in the hemoglobin level was -1.8 g per deciliter and -1.9 g per deciliter, respectively (mean difference, -0.1 g per deciliter; 95% CI, -0.2 to -0.1); and postpartum infectious complications occurred in 3.2% and 2.5% of the participants, respectively (relative risk, 1.28; 95% CI, 1.02 to 1.61). The frequencies of thromboembolic events and other adverse events were similar in the two groups. CONCLUSIONS: Prophylactic use of tranexamic acid during cesarean delivery did not lead to a significantly lower risk of a composite outcome of maternal death or blood transfusion than placebo. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT03364491.).


Assuntos
Antifibrinolíticos , Cesárea , Hemorragia Pós-Parto , Ácido Tranexâmico , Criança , Feminino , Humanos , Gravidez , Antifibrinolíticos/efeitos adversos , Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica/mortalidade , Perda Sanguínea Cirúrgica/prevenção & controle , Hemoglobinas/análise , Morte Materna , Ácido Tranexâmico/efeitos adversos , Ácido Tranexâmico/uso terapêutico , Hemorragia Pós-Parto/sangue , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/mortalidade , Hemorragia Pós-Parto/prevenção & controle , Cesárea/efeitos adversos , Transfusão de Sangue , Quimioprevenção
4.
EMBO Rep ; 24(1): e56075, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36330771

RESUMO

Mitosis leads to global downregulation of transcription that then needs to be efficiently resumed. In somatic cells, this is mediated by a transient hyper-active state that first reactivates housekeeping and then cell identity genes. Here, we show that mouse embryonic stem cells, which display rapid cell cycles and spend little time in G1, also display accelerated reactivation dynamics. This uniquely fast global reactivation lacks specificity towards functional gene families, enabling the restoration of all regulatory functions before DNA replication. Genes displaying the fastest reactivation are bound by CTCF, a mitotic bookmarking transcription factor. In spite of this, the post-mitotic global burst is robust and largely insensitive to CTCF depletion. There are, however, around 350 genes that respond to CTCF depletion rapidly after mitotic exit. Remarkably, these are characterised by promoter-proximal mitotic bookmarking by CTCF. We propose that the structure of the cell cycle imposes distinct constrains to post-mitotic gene reactivation dynamics in different cell types, via mechanisms that are yet to be identified but that can be modulated by mitotic bookmarking factors.


Assuntos
Células-Tronco Embrionárias Murinas , Fatores de Transcrição , Animais , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica , Ciclo Celular , Células-Tronco Embrionárias/metabolismo , Mitose/genética , Cromatina
5.
Am J Obstet Gynecol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969197

RESUMO

Fluid management in obstetric care is crucial due to the complex physiological conditions of pregnancy, which complicate clinical manifestations and fluid balance management. This expert review examines the use of point-of-care ultrasound (POCUS) to evaluate and monitor the response to fluid therapy in pregnant patients. Pregnancy induces significant physiological changes, including increased cardiac output and glomerular filtration rate, decreased systemic vascular resistance, and plasma oncotic pressure. Conditions like preeclampsia further complicate fluid management due to decreased intravascular volume and increased capillary permeability. Traditional methods of assessing fluid volume status, such as physical examination and invasive monitoring, are often unreliable or inappropriate. POCUS provides a non-invasive, rapid, and reliable means to assess fluid responsiveness, which is essential in managing fluid therapy in pregnant patients. This review details various POCUS modalities used to measure dynamic changes in fluid status, focusing on the evaluation of the inferior vena cava (IVC), lung ultrasound (Lung US), and the left ventricular outflow tract (LVOT). IVC ultrasound in spontaneously breathing patients determines diameter variability, predicting fluid responsiveness and being feasible even late in pregnancy. Lung ultrasound is critical for detecting early signs of pulmonary edema before clinical symptoms arise and is more accurate than traditional radiography. The LVOT velocity-time integral (VTI) assesses stroke volume response to fluid challenges, providing a quantifiable measure of cardiac function, especially beneficial in critical care settings where rapid and accurate fluid management is essential. The expert review synthesizes current evidence and practice guidelines, suggesting integrating POCUS as a fundamental aspect of fluid management in obstetrics. It calls for ongoing research to enhance techniques and validate their use in broader clinical settings, aiming to improve outcomes for pregnant patients and their babies by preventing complications associated with both under- and over-resuscitation.

6.
Am J Obstet Gynecol ; 230(5): 567.e1-567.e11, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38367749

RESUMO

BACKGROUND: The optimal timing of amniotomy during labor induction is a topic of ongoing debate due to the potential risks associated with both amniotomy and prolonged labor. As such, individuals in the field of obstetrics and gynecology must carefully evaluate the associated benefits and drawbacks of this procedure. While amniotomy can expedite the labor process, it may also lead to complications such as umbilical cord prolapse, fetal distress, and infection. Therefore, a careful and thorough examination of the risks and benefits of amniotomy during labor induction is essential in making an informed decision regarding the optimal timing of this procedure. OBJECTIVE: This study aimed to determine if an amniotomy within 2 hours after Foley balloon removal reduced the duration of active labor and time taken to achieve vaginal delivery when compared with an amniotomy ≥4 hours after balloon removal among term pregnant women who underwent labor induction. STUDY DESIGN: This was an open-label, randomized controlled trial that was conducted at a single academic center from October 2020 to March 2023. Term participants who were eligible for preinduction cervical ripening with a Foley balloon were randomized into 2 groups, namely the early amniotomy (rupture of membranes within 2 hours after Foley balloon removal) and delayed amniotomy (rupture of membranes performed more than 4 hours after Foley balloon removal) groups. Randomization was stratified by parity. The primary outcome was time from Foley balloon insertion to active phase of labor. Secondary outcomes, including time to delivery, cesarean delivery rates, and maternal and neonatal complications, were analyzed using intention-to-treat and per-protocol analyses. RESULTS: Of the 150 participants who consented and were enrolled, 149 were included in the analysis. In the intention-to-treat population, an early amniotomy did not significantly shorten the time between Foley balloon insertion and active labor when compared with a delayed amniotomy (885 vs 975 minutes; P=.08). An early amniotomy was associated with a significantly shorter time from Foley balloon placement to active labor in nulliparous individuals (1211; 584-2340 vs 1585; 683-2760; P=.02). When evaluating the secondary outcomes, an early amniotomy was associated with a significantly shorter time to active labor onset (312.5 vs 442.5 minutes; P=.02) and delivery (484 vs 587 minutes; P=.03) from Foley balloon removal with a higher rate of delivery within 36 hours (96% vs 85%; P=.03). Individuals in the early amniotomy group reached active labor 1.5 times faster after Foley balloon insertion than those in the delayed group (hazard ratio, 1.5; 95% confidence interval, 1.1-2.2; P=.02). Those with an early amniotomy also reached vaginal delivery 1.5 times faster after Foley balloon removal than those in the delayed group (hazard ratio, 1.5; 95% confidence interval, 1-2.2; P=.03). A delayed amniotomy was associated with a higher rate of postpartum hemorrhage (0% vs 9.5%; P=.01). No significant differences were observed in the cesarean delivery rates, length of hospital stay, maternal infection, or neonatal outcomes. CONCLUSION: Although an early amniotomy does not shorten the time from Foley balloon insertion to active labor, it shortens time from Foley balloon removal to active labor and delivery without increasing complications. The increased postpartum hemorrhage rate in the delayed amniotomy group suggests increased risks with delayed amniotomy.


Assuntos
Amniotomia , Maturidade Cervical , Trabalho de Parto Induzido , Humanos , Feminino , Trabalho de Parto Induzido/métodos , Gravidez , Adulto , Amniotomia/métodos , Fatores de Tempo , Cateterismo/métodos , Parto Obstétrico/métodos
7.
Am J Perinatol ; 41(S 01): e3391-e3400, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38134939

RESUMO

OBJECTIVE: Prediction of blood transfusion during delivery admission allows for clinical preparedness and risk mitigation. Although prediction models have been developed and adopted into practice, their external validation is limited. We aimed to evaluate the performance of three blood transfusion prediction models in a U.S. cohort of individuals undergoing cesarean delivery. STUDY DESIGN: This was a secondary analysis of a multicenter randomized trial of tranexamic acid for prevention of hemorrhage at time of cesarean delivery. Three models were considered: a categorical risk tool (California Maternal Quality Care Collaborative [CMQCC]) and two regression models (Ahmadzia et al and Albright et al). The primary outcome was intrapartum or postpartum red blood cell transfusion. The CMQCC algorithm was applied to the cohort with frequency of risk category (low, medium, high) and associated transfusion rates reported. For the regression models, the area under the receiver-operating curve (AUC) was calculated and a calibration curve plotted to evaluate each model's capacity to predict receipt of transfusion. The regression model outputs were statistically compared. RESULTS: Of 10,785 analyzed individuals, 3.9% received a red blood cell transfusion during delivery admission. The CMQCC risk tool categorized 1,970 (18.3%) individuals as low risk, 5,259 (48.8%) as medium risk, and 3,556 (33.0%) as high risk with corresponding transfusion rates of 2.1% (95% confidence interval [CI]: 1.5-2.9%), 2.2% (95% CI: 1.8-2.6%), and 7.5% (95% CI: 6.6-8.4%), respectively. The AUC for prediction of blood transfusion using the Ahmadzia and Albright models was 0.78 (95% CI: 0.76-0.81) and 0.79 (95% CI: 0.77-0.82), respectively (p = 0.38 for difference). Calibration curves demonstrated overall agreement between the predicted probability and observed likelihood of blood transfusion. CONCLUSION: Three models were externally validated for prediction of blood transfusion during cesarean delivery admission in this U.S. COHORT: Overall, performance was moderate; model selection should be based on ease of application until a specific model with superior predictive ability is developed. KEY POINTS: · A total of 3.9% of individuals received a blood transfusion during cesarean delivery admission.. · Three models used in clinical practice are externally valid for blood transfusion prediction.. · Institutional model selection should be based on ease of application until further research identifies the optimal approach..


Assuntos
Transfusão de Sangue , Cesárea , Adulto , Feminino , Humanos , Gravidez , Algoritmos , Antifibrinolíticos/uso terapêutico , Área Sob a Curva , Transfusão de Sangue/estatística & dados numéricos , Transfusão de Eritrócitos , Hemorragia Pós-Parto/terapia , Medição de Risco/métodos , Curva ROC , Ácido Tranexâmico/uso terapêutico , Estados Unidos
8.
Sensors (Basel) ; 24(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38894396

RESUMO

The growing use of Unmanned Aerial Vehicles (UAVs) raises the need to improve their autonomous navigation capabilities. Visual odometry allows for dispensing positioning systems, such as GPS, especially on indoor flights. This paper reports an effort toward UAV autonomous navigation by proposing a translational velocity observer based on inertial and visual measurements for a quadrotor. The proposed observer complementarily fuses available measurements from different domains and is synthesized following the Immersion and Invariance observer design technique. A formal Lyapunov-based observer error convergence to zero is provided. The proposed observer algorithm is evaluated using numerical simulations in the Parrot Mambo Minidrone App from Simulink-Matlab.

9.
Clin Exp Allergy ; 53(2): 198-209, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36176209

RESUMO

BACKGROUND: Allergen-specific immunotherapy (AIT) is the only clinical approach that can potentially cure some allergic diseases by inducing immunological tolerance. Dermatophagoides pteronyssinus is considered as the most important source of mite allergens worldwide, with high sensitization rates for the major allergens Der p 1, Der p 2 and Der p 23. The aim of this work is to generate a hypoallergenic hybrid molecule containing T-cell epitopes from these three major allergens. METHODS: The hybrid protein termed Der p 2231 containing T-cell epitopes was purified by affinity chromatography. The human IgE reactivity was verified by comparing those with the parental allergens. The hybrid was also characterized immunologically through an in vivo mice model. RESULTS: The hybrid rDer p 2231 stimulated in peripheral blood mononuclear cells (PBMCs) isolated from allergic patients with higher levels of IL- 2, IL-10, IL-15 and IFN-γ, as well as lower levels of IL-4, IL-5, IL-13, TNF-α and GM-CSF. The use of hybrid molecules as a therapeutic model in D. pteronyssinus allergic mice led to the reduction of IgE production and lower eosinophilic peroxidase activity in the airways. We found increased levels of IgG antibodies that blocked the IgE binding to the parental allergens in the serum of allergic patients. Furthermore, the stimulation of splenocytes from mice treated with rDer p 2231 induced higher levels of IL-10 and IFN-γ and decreased the secretion of IL-4 and IL-5, when compared with parental allergens and D. pteronyssinus extract. CONCLUSIONS: rDer p 2231 has the potential to be used in AIT in patients co-sensitized with D. pteronyssinus major allergens, once it was able to reduce IgE production, inducing allergen-specific blocking antibodies, restoring and balancing Th1/Th2 immune responses, and inducing regulatory T-cells.


Assuntos
Antígenos de Dermatophagoides , Epitopos de Linfócito T , Hipersensibilidade , Animais , Humanos , Camundongos , Alérgenos , Antígenos de Dermatophagoides/imunologia , Antígenos de Dermatophagoides/farmacologia , Antígenos de Dermatophagoides/uso terapêutico , Proteínas de Artrópodes , Dermatophagoides pteronyssinus , Epitopos de Linfócito T/química , Epitopos de Linfócito T/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Imunoglobulina E , Interleucina-10 , Interleucina-4 , Interleucina-5 , Leucócitos Mononucleares , Pyroglyphidae , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Imunoterapia/métodos
10.
Clin Exp Allergy ; 53(8): 821-832, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36779555

RESUMO

BACKGROUND: Allergen-specific immunotherapy (AIT) is the only disease-modifying treatment approach to change disease-causing allergens. Hypoallergenic derivatives show promise as potential therapeutics, amongst which BTH2 was designed to induce tolerance against Blomia tropicalis allergy. Our aim was to investigate the hypoallergenicity and immunoregulatory activity of BTH2 in vitro and its therapeutic potential in a mouse model of AIT. METHODS: Recombinant Blo t 5 and Blo t 21 allergens and their hybrid derivatives (BTH1 and BTH2) were expressed and purified. IgE binding capacity was tested by ELISA using sera from Brazilian, Colombian, and Ecuadorian subjects. Secretion of cytokines in supernatants from human cell cultures was measured following stimulation with the four recombinants and controls. The capacity of BTH2 to ameliorate allergic airway inflammation induced by B. tropicalis extract was evaluated in a murine model of AIT. RESULTS: rBlo t 5 and rBlo t 21 were identified as major allergens in Latin American patients, and BTH2 had the lowest IgE binding. In vitro stimulation of human cells induced greater levels of IL-10 and IFN-γ and reduced the secretion of Th2 cytokines. BTH2 ameliorated allergic airway inflammation in B. tropicalis-challenged A/J mice, as evidenced by the histopathological and humoral biomarkers: decreased Th2 cytokines and cellular infiltration (especially eosinophils), lower activity of eosinophil peroxidase, an increase in IgG blocking antibodies and strong reduction of mucus production by goblet cells. CONCLUSIONS: Our study shows that BTH2 represents a promising candidate for the treatment of B. tropicalis allergy with hypoallergenic, immune regulatory and therapeutic properties. Further pre-clinical studies are required in murine models of chronic asthma to further address the efficacy and safety of BTH2 as a vaccine against B. tropicalis-induced allergy.


Assuntos
Hipersensibilidade , Humanos , Camundongos , Animais , Modelos Animais de Doenças , Hipersensibilidade/terapia , Alérgenos , Inflamação , Citocinas , Dessensibilização Imunológica , Imunoglobulina E
11.
Am J Obstet Gynecol ; 229(3): B2-B19, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37236495

RESUMO

Maternal sepsis is a significant cause of maternal morbidity and mortality, and is a potentially preventable cause of maternal death. This Consult aims to summarize what is known about sepsis and provide guidance for the management of sepsis during pregnancy and the postpartum period. Most studies cited are from the nonpregnant population, but where available, pregnancy data are included. The following are the Society for Maternal-Fetal Medicine recommendations: (1) we recommend that clinicians consider the diagnosis of sepsis in pregnant or postpartum patients with otherwise unexplained end-organ damage in the presence of a suspected or confirmed infectious process, regardless of the presence of fever (GRADE 1C); (2) we recommend that sepsis and septic shock in pregnancy be considered medical emergencies and that treatment and resuscitation begin immediately (Best Practice); (3) we recommend that hospitals and health systems use a performance improvement program for sepsis in pregnancy with sepsis screening tools and metrics (GRADE 1B); (4) we recommend that institutions develop their own procedures and protocols for the detection of maternal sepsis, avoiding the use of a single screening tool alone (GRADE 1B); (5) we recommend obtaining tests to evaluate for infectious and noninfectious causes of life-threatening organ dysfunction in pregnant and postpartum patients with possible sepsis (Best Practice); (6) we recommend that an evaluation for infectious causes in pregnant or postpartum patients in whom sepsis is suspected or identified includes appropriate microbiologic cultures, including blood, before starting antimicrobial therapy, as long as there are no substantial delays in timely administration of antibiotics (Best Practice); (7) we recommend obtaining a serum lactate level in pregnant or postpartum patients in whom sepsis is suspected or identified (GRADE 1B); (8) in pregnant or postpartum patients with septic shock or a high likelihood of sepsis, we recommend administration of empiric broad-spectrum antimicrobial therapy, ideally within 1 hour of recognition (GRADE 1C); (9) after a diagnosis of sepsis in pregnancy is made, we recommend rapid identification or exclusion of an anatomic source of infection and emergency source control when indicated (Best Practice); (10) we recommend early intravenous administration (within the first 3 hours) of 1 to 2 L of balanced crystalloid solutions in sepsis complicated by hypotension or suspected organ hypoperfusion (GRADE 1C); (11) we recommend the use of a balanced crystalloid solution as a first-line fluid for resuscitation in pregnant and postpartum patients with sepsis or septic shock (GRADE 1B); (12) we recommend against the use of starches or gelatin for resuscitation in pregnant and postpartum patients with sepsis or septic shock (GRADE 1A); (13) we recommend ongoing, detailed evaluation of the patient's response to fluid resuscitation guided by dynamic measures of preload (GRADE 1B); (14) we recommend the use of norepinephrine as the first-line vasopressor during pregnancy and the postpartum period with septic shock (GRADE 1C); (15) we suggest using intravenous corticosteroids in pregnant or postpartum patients with septic shock who continue to require vasopressor therapy (GRADE 2B); (16) because of an increased risk of venous thromboembolism in sepsis and septic shock, we recommend the use of pharmacologic venous thromboembolism prophylaxis in pregnant and postpartum patients in septic shock (GRADE 1B); (17) we suggest initiating insulin therapy at a glucose level >180 mg/dL in critically ill pregnant patients with sepsis (GRADE 2C); (18) if a uterine source for sepsis is suspected or confirmed, we recommend prompt delivery or evacuation of uterine contents to achieve source control, regardless of gestational age (GRADE 1C); and (19) because of an increased risk of physical, cognitive, and emotional problems in survivors of sepsis and septic shock, we recommend ongoing comprehensive support for pregnant and postpartum sepsis survivors and their families (Best Practice).


Assuntos
Pré-Eclâmpsia , Complicações Infecciosas na Gravidez , Sepse , Choque Séptico , Tromboembolia Venosa , Gravidez , Feminino , Humanos , Choque Séptico/diagnóstico , Choque Séptico/terapia , Perinatologia , Sepse/diagnóstico , Sepse/terapia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/terapia
12.
Am J Obstet Gynecol ; 228(1): 22-35.e2, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35932873

RESUMO

OBJECTIVE: This study aimed to evaluate the risk of endometrial carcinoma and atypical endometrial hyperplasia in asymptomatic postmenopausal women concerning the endometrial thickness measured by stratified threshold categories used for performing subsequent endometrial sampling and histologic evaluation. DATA SOURCES: MEDLINE, Scopus, ClinicalTrials.gov, SciELO, Embase, the Cochrane Central Register of Controlled Trials, LILACS, conference proceedings, and international controlled trials registries were searched without temporal, geographic, or language restrictions. STUDY ELIGIBILITY CRITERIA: Studies were selected if they had a crossover design evaluating the risk of atypical endometrial hyperplasia and endometrial carcinoma in postmenopausal asymptomatic women and calculated the diagnostic accuracy of transvaginal ultrasonography thresholds (at least 3.0 mm) confirmed by histopathologic diagnosis. METHODS: This was a systematic review and diagnostic test accuracy meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy and Synthesizing Evidence from Diagnostic Accuracy Tests guidelines. Endometrial thickness thresholds were grouped as follows: from 3.0 to 5.9 mm; between 6.0 and 9.9 mm; between 10.0 and 13.9 mm; and ≥14.0 mm. Quality assessment was performed using the Quality Assessment Tool for Diagnostic Accuracy Studies 2 tool. Publication bias was quantified using the Deek funnel plot test. Coprimary outcomes were the risk of atypical endometrial hyperplasia or endometrial carcinoma according to the endometrial thickness and diagnostic accuracy of each threshold group. RESULTS: A total of 18 studies provided the data of 10,334 women who were all included in the final analysis. Overall, at an endometrial thickness threshold of at least 3.0 mm, the risk of atypical endometrial hyperplasia or endometrial carcinoma was increased 3-fold relative to women below the cutoff (relative risk, 3.77; 95% confidence interval, 2.26-6.32; I2=74%). Similar degrees of risk were reported for thresholds between 3.0 and 5.9 mm (relative risk, 5.08; 95% confidence interval, 2.26-11.41; I2=0%), 6.0 and 9.9 mm (relative risk, 4.34; 95% confidence interval, 1.68-11.23; I2=0%), 10.0 and 13.9 mm (relative risk, 4.11; 95% confidence interval, 1.55-10.87; I2=86%), and ≥14.0 mm (relative risk, 2.53; 95% confidence interval, 1.04-6.16; I2=78%) with no significant difference among subgroups (P=.885). Regarding diagnostic accuracy, the pooled sensitivity decreased from thresholds below 5.9 mm (relative risk, 0.81; 95% confidence interval, 0.49-0.85) to above 14.0 mm (relative risk, 0.28; 95% confidence interval, 0.18-0.40). Furthermore, the specificity increased from 0.70 (95% confidence interval, 0.61-0.78) for endometrial thickness between 3.0 and 5.9 mm to 0.86 (95% confidence interval, 0.71-0.94) when the endometrial thickness is ≥14.0 mm. For 3.0 to 5.9 mm and 10.0 to 13.9 mm thresholds, the highest diagnostic odds ratios of 10 (95% confidence interval, 3-41) and 11 (95% confidence interval, 2-49), with areas under the curve of 0.81 (95% confidence interval, 0.77-0.84) and 0.82 (95% confidence interval, 0.79-0.86), respectively, were retrieved. The summary point analysis revealed that the 3.0 to 5.9 mm cutoff point was placed higher in the summary receiver operator curve space than the other subgroups, indicating increased endometrial carcinoma or atypical endometrial hyperplasia diagnosis using these cutoffs. CONCLUSION: Both low and high endometrial thickness thresholds in postmenopausal asymptomatic women seem equally effective in detecting endometrial carcinoma and atypical endometrial hyperplasia. However, although using a 3.0 to 5.9 mm cutoff results in a lower specificity, the offsetting improvement in sensitivity may justify using this cutoff for further endometrial evaluation in patients with suspected endometrial malignancy.


Assuntos
Hiperplasia Endometrial , Neoplasias do Endométrio , Feminino , Humanos , Testes Diagnósticos de Rotina , Hiperplasia Endometrial/diagnóstico por imagem , Hiperplasia Endometrial/patologia , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/patologia , Pós-Menopausa , Sensibilidade e Especificidade , Ultrassonografia/métodos
13.
Clin Obstet Gynecol ; 66(1): 151-162, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36044634

RESUMO

In the last 2 decades, the use of venovenous (VV) and venoarterial (VA) extracorporeal membrane oxygenation (ECMO) during pregnancy and the postpartum period has increased, mirroring the increased utilization in nonpregnant individuals worldwide. VV ECMO provides respiratory support for patients with acute respiratory distress syndrome (ARDS) who fail conventional mechanical ventilation. With the COVID-19 pandemic, the use of VV ECMO has increased dramatically and data during pregnancy and the postpartum period are overall reassuring. In contrast, VA ECMO provides both respiratory and cardiovascular support. Data on the use of VA ECMO during pregnancy are extremely limited.


Assuntos
Oxigenação por Membrana Extracorpórea , Feminino , Humanos , Gravidez , COVID-19/epidemiologia , COVID-19/terapia , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Pandemias , Respiração Artificial , Falha de Tratamento , Síndrome do Desconforto Respiratório/terapia
14.
Clin Obstet Gynecol ; 66(1): 163-175, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162092

RESUMO

Cardiac disease is the most common cause of maternal mortality in developed nations. Cardiac arrhythmias are frequent among patients with structural heart disease and may require immediate treatment to prevent hemodynamic instability leading to acute maternal and fetal decompensation. Antiarrhythmic therapy during pregnancy should follow the same principles recommended for nonpregnant individuals. Although multidisciplinary management is recommended, obstetricians, and maternal-fetal medicine specialists may sometimes need to emergently recognize and treat rhythm anomalies before support services become available.


Assuntos
Antiarrítmicos , Arritmias Cardíacas , Gravidez , Feminino , Humanos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/terapia , Antiarrítmicos/uso terapêutico , Cuidado Pré-Natal , Perinatologia , Feto
15.
Gynecol Obstet Invest ; 88(6): 336-348, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37899034

RESUMO

INTRODUCTION: Usefulness of hysteroscopy before assisted reproductive technique (ART) was considered debatable. However, over the last decade, several new trials have been added to available literature. We aimed to assess the impact of diagnostic and operative hysteroscopy on reproductive outcomes of infertile women with and without intrauterine abnormalities. MATERIALS AND METHODS: MEDLINE, Scopus, SciELO, Embase, Cochrane Library at CENTRAL, PROSPERO, CINAHL, grey literature, conference proceedings, and international controlled trials registries were searched without temporal, geographical, or language restrictions. Randomized controlled trials (RCTs) of infertile women comparing hysteroscopy versus no hysteroscopy prior to the first ART or after at least one failed attempt were included. RCTs of infertile women with intrauterine pathology comparing diagnostic versus operative hysteroscopy were included in separate analysis. Random-effect meta-analysis was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Grading of Recommendations, Assessment, Development and Evaluation and Cochrane criteria were used for quality of evidence and risk of bias assessment. Primary outcome was live birth rate (LBR). Secondary outcomes were clinical pregnancy (CPR) and pregnancy loss rate. RESULTS: Fifteen studies (5,038 women) were included. Compared to no hysteroscopy before first or after failed ART attempts, moderate-quality evidence showed that hysteroscopy increased the LBR (relative risk [RR] 1.24, 95% confidence interval [CI] 1.09-1.43, I2 = 21%), confirmed by subgroup analysis for women with failure after one or more ART cycles (RR 1.43, 95% CI: 1.19-1.72, I2 = 0%) but not before the first ART. Moderate-quality evidence showed that it increased the CPR (RR 1.36, 95% CI: 1.18-1.57; I2 = 51%), confirmed in subgroup analysis for both implantation failure (RR 1.40, 95% CI: 1.12-1.74, I2 = 52%) and before first ART (RR 1.32, 95% CI: 1.11-1.57, I2 = 42%). Low-quality data suggest that operative hysteroscopy increases CPR when used to treat intrauterine pathologies (RR 2.13, 95% CI: 1.56-2.92, I2 = 0%). CONCLUSIONS: Although moderate-quality evidence supports performing hysteroscopy before ART in women with history of implantation failure, hysteroscopic evaluation of uterine cavity should be considered a first-line technique in all infertile women undergoing ART. Additional high-quality RCTs are still needed, particularly to assess yield during couple's initial evaluation even before ART is considered.


Assuntos
Histeroscopia , Infertilidade Feminina , Gravidez , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Infertilidade Feminina/cirurgia , Útero , Taxa de Gravidez , Técnicas de Reprodução Assistida , Fertilidade , Nascido Vivo
16.
Funct Integr Genomics ; 23(1): 5, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36534203

RESUMO

Corynebacterium striatum, a common constituent of the human skin microbiome, is now considered an emerging multidrug-resistant pathogen of immunocompromised and chronically ill patients. However, little is known about the molecular mechanisms in the transition from colonization to the multidrug-resistant (MDR) invasive phenotype in clinical isolates. This study performed a comprehensive pan-genomic analysis of C. striatum, including isolates from "normal skin microbiome" and from MDR infections, to gain insights into genetic factors contributing to pathogenicity and multidrug resistance in this species. For this, three novel genome sequences were obtained from clinical isolates of C. striatum of patients from Brazil, and other 24 complete or draft C. striatum genomes were retrieved from GenBank, including the ATCC6940 isolate from the Human Microbiome Project. Analysis of C. striatum strains demonstrated the presence of an open pan-genome (α = 0.852803) containing 3816 gene families, including 15 antimicrobial resistance (AMR) genes and 32 putative virulence factors. The core and accessory genomes included 1297 and 1307 genes, respectively. The identified AMR genes are primarily associated with resistance to aminoglycosides and tetracyclines. Of these, 66.6% are present in genomic islands, and four AMR genes, including aac(6')-ib7, are located in a class 1-integron. In conclusion, our data indicated that C. striatum possesses genomic characteristics favorable to the invasive phenotype, with high genomic plasticity, a robust genetic arsenal for iron acquisition, and important virulence determinants and AMR genes present in mobile genetic elements.


Assuntos
Antibacterianos , Corynebacterium , Humanos , Fenótipo , Fatores de Virulência/genética , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana
17.
Protein Expr Purif ; 199: 106150, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35944614

RESUMO

Common strategies to improve recombinant protein production in Escherichia coli often involve the test and optimization of several different variables, when using traditional expression vectors that are commercially available. Now, modern synthetic biology-based strategies allow for extensive modifications of these traditional vectors, or even construction of entirely new modular vectors, so as to permit tunable production of the recombinant proteins of interest. Herein, we describe the engineering of a new expression operating unit (EOU; 938 bp) for producing recombinant proteins in E. coli, through the combinatorial assembly of standardized and well-characterized genetic elements required for transcription and translation (promoter, operator site, RBS, junction RBS-CDS, cloning module, transcriptional terminator). We also constructed a novel T7 promoter variant with increased transcriptional activity (1.7-fold higher), when compared to the canonical wild type T7 promoter sequence. This new EOU yielded an improved production of the reporter protein superfolder GFP (sfGFP) in E. coli BL21(DE3) (relative fluorescence units/RFU = 70.62 ± 1.62 A U.) when compared to a high-producing control expression vector (plasmid BBa_I746909; RFU = 59.68 ± 1.82 A U.). The yields of purified soluble recombinant sfGFP were also higher when using the new EOU (188 mg L-1 culture vs. 108 mg L-1 in the control) and it performed similarly well when inserted into different plasmid backbones (pOPT1.0/AmpR and pOPT2.0/CmR).


Assuntos
Escherichia coli , Vetores Genéticos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
Am J Obstet Gynecol ; 227(2): B28-B43, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35337804

RESUMO

Pregnancy in individuals with a mechanical heart valve has been classified as very high risk because of a substantially increased risk of maternal mortality or severe morbidity. Lifelong therapeutic anticoagulation is a principal component of the medical management of mechanical heart valves to prevent valve thrombosis. Anticoagulation regimens indicated outside of pregnancy for patients with mechanical valves should be continued during pregnancy with the possibility of modifications based on the type of valve, the trimester of pregnancy, individual risk tolerance, and circumstances around the time of delivery. The purpose of this document is to provide recommendations regarding the management of anticoagulation for common cardiac conditions complicating pregnancy, including mechanical heart valves, atrial fibrillation, systolic heart failure, and congenital heart disease.


Assuntos
Complicações Cardiovasculares na Gravidez , Tromboembolia , Anticoagulantes/uso terapêutico , Arritmias Cardíacas , Feminino , Humanos , Perinatologia , Gravidez , Complicações Cardiovasculares na Gravidez/induzido quimicamente , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/prevenção & controle , Tromboembolia/prevenção & controle
19.
Am J Obstet Gynecol ; 226(4): 487-498.e8, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34555319

RESUMO

OBJECTIVE: To assess the efficacy of mechanical strategies to avoid the recurrence of intrauterine adhesions, to evaluate the impact on subsequent fertility after hysteroscopic adhesiolysis and to rank the available antiadhesive options. DATA SOURCES: MEDLINE, Scopus, ClinicalTrials.gov, CINAHL, Scielo, EMBASE, PROSPERO, Cochrane Library, conference proceedings, and international controlled trials registries were searched without temporal, geographic, and language restrictions. STUDY ELIGIBILITY CRITERIA: Randomized trials that analyzed the recurrence, reproductive outcomes, or both in women undergoing hysteroscopic adhesiolysis followed by mechanical prevention of intrauterine adhesions were included. The exclusion criteria included the following: quasi-randomized trials and trials without randomization and studies including patients undergoing hysteroscopic surgery that was different from adhesiolysis. STUDY APPRAISAL AND SYNTHESIS METHODS: The Preferred Reporting Items for Systematic reviews and Meta-Analyses extension statement for network meta-analyses guidelines were followed. We performed a network meta-analysis based on the random effects model for mixed multiple treatment comparisons to rank the antiadhesive strategies by surface under the cumulative ranking curve area. Quality assessment was performed using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions. The primary outcome was the recurrent presence of intrauterine adhesions. RESULTS: Eleven studies with data for 1596 women were identified as applicable. A copper intrauterine device together with an intrauterine balloon (surface under the cumulative ranking curve area=46.4%) or with cross-linked hyaluronic acid gel (surface under the cumulative ranking curve area=21.3%) seemed effective in preventing adhesions recurrence. Regarding the fecundity, hyaluronic acid gel demonstrated the highest pregnancy rates (surface under the cumulative ranking curve area=79.8%). The greatest degrees of change in the mean adhesions scores were found with the use of hyaluronic acid gel plus an intrauterine device (surface under the cumulative ranking curve area=38.9%). For postsurgical adhesion severity, hyaluronic acid gel plus intrauterine device (surface under the cumulative ranking curve area=49.9%) followed by intrauterine device alone (surface under the cumulative ranking curve area=30.8%) was ranked the highest. Dried amnion graft (surface under the cumulative ranking curve area=53.8%) and uterine balloon (surface under the cumulative ranking curve area=45%) showed the greatest menstrual pattern improvement. CONCLUSION: Cross-linked hyaluronic acid gel, with or without insertion of a copper intrauterine device, seems to be the most effective approach. However, the lack of a clear best therapy suggests the need for further studies to draw firm conclusions.


Assuntos
Doenças Uterinas , Feminino , Humanos , Histeroscopia , Metanálise em Rede , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Aderências Teciduais/prevenção & controle , Aderências Teciduais/cirurgia , Doenças Uterinas/prevenção & controle , Doenças Uterinas/cirurgia
20.
Am J Perinatol ; 39(9): 930-936, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33242907

RESUMO

Maternal mortality has increased in the last decades in the United States as a result of increased prevalence of coexisting medical diseases such as hypertension, diabetes, and both acquired and congenital heart diseases. Obstetricians and maternal-fetal medicine physicians should have the basic medical knowledge to initiate appropriate diagnostic and early therapeutic interventions since they may be the only provider available at the time of presentation. The goal of this article is not to extensively discuss the management of complex medical diseases during pregnancy, rather we provide a concise review of key early medical interventions that will likely result in improved clinical outcomes. KEY POINTS: · Obstetricians and maternal-fetal medicine physicians must be familiar with initial basic management of common medical emergencies.. · Management of these complex cases is ideally multidisciplinary.. · Residency/fellowship programs should include common disease management to improve maternal outcomes..


Assuntos
Emergências , Mortalidade Materna , Feminino , Humanos , Gravidez , Estados Unidos
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