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1.
Ultrasound Obstet Gynecol ; 62(1): 75-87, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37099500

RESUMO

OBJECTIVE: Fetuses with congenital heart disease (CHD) are at increased risk of pregnancy loss compared with the general population. We aimed to assess the incidence, timing and risk factors of pregnancy loss in cases with major fetal CHD, overall and according to cardiac diagnosis. METHODS: This was a retrospective, population-level cohort study of fetuses and infants diagnosed with major CHD between 1997 and 2018 identified by the Utah Birth Defect Network (UBDN), excluding cases with termination of pregnancy and minor cardiovascular diagnoses (e.g. isolated aortic/pulmonary pathology and isolated septal defects). The incidence and timing of pregnancy loss were recorded, overall and according to CHD diagnosis, with further stratification based on presence of isolated CHD vs additional fetal diagnosis (genetic diagnosis and/or extracardiac malformation). Adjusted risk of pregnancy loss was calculated and risk factors were assessed using multivariable models for the overall cohort and prenatal diagnosis subgroup. RESULTS: Of 9351 UBDN cases with a cardiovascular code, 3251 cases with major CHD were identified, resulting in a study cohort of 3120 following exclusion of cases with pregnancy termination (n = 131). There were 2956 (94.7%) live births and 164 (5.3%) cases of pregnancy loss, which occurred at a median gestational age of 27.3 weeks. Of study cases, 1848 (59.2%) had isolated CHD and 1272 (40.8%) had an additional fetal diagnosis, including 736 (57.9%) with a genetic diagnosis and 536 (42.1%) with an extracardiac malformation. The observed incidence of pregnancy loss was highest in the presence of mitral stenosis (< 13.5%), hypoplastic left heart syndrome (HLHS) (10.7%), double-outlet right ventricle with normally related great vessels or not otherwise specified (10.5%) and Ebstein's anomaly (9.9%). The adjusted risk of pregnancy loss was 5.3% (95% CI, 3.7-7.6%) in the overall CHD population and 1.4% (95% CI, 0.9-2.3%) in cases with isolated CHD (adjusted risk ratio, 9.0 (95% CI, 6.0-13.0) and 2.0 (95% CI, 1.0-6.0), respectively, based on the general population risk of 0.6%). On multivariable analysis, variables associated with pregnancy loss in the overall CHD population included female fetal sex (adjusted odds ratio (aOR), 1.6 (95% CI, 1.1-2.3)), Hispanic ethnicity (aOR, 1.6 (95% CI, 1.0-2.5)), hydrops (aOR, 6.7 (95% CI, 4.3-10.5)) and additional fetal diagnosis (aOR, 6.3 (95% CI, 4.1-10)). On multivariable analysis of the prenatal diagnosis subgroup, years of maternal education (aOR, 1.2 (95% CI, 1.0-1.4)), presence of an additional fetal diagnosis (aOR, 2.7 (95% CI, 1.4-5.6)), atrioventricular valve regurgitation ≥ moderate (aOR, 3.6 (95% CI, 1.3-8.8)) and ventricular dysfunction (aOR, 3.8 (95% CI, 1.2-11.1)) were associated with pregnancy loss. Diagnostic groups associated with pregnancy loss were HLHS and variants (aOR, 3.0 (95% CI, 1.7-5.3)), other single ventricles (aOR, 2.4 (95% CI, 1.1-4.9)) and other (aOR, 0.1 (95% CI, 0-0.97)). Time-to-pregnancy-loss analysis demonstrated a steeper survival curve for cases with an additional fetal diagnosis, indicating a higher rate of pregnancy loss compared to cases with isolated CHD (P < 0.0001). CONCLUSIONS: The risk of pregnancy loss is higher in cases with major fetal CHD compared with the general population and varies according to CHD type and presence of additional fetal diagnoses. Improved understanding of the incidence, risk factors and timing of pregnancy loss in CHD cases should inform patient counseling, antenatal surveillance and delivery planning. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Aborto Induzido , Aborto Espontâneo , Coração Fetal , Cardiopatias Congênitas , Feminino , Humanos , Lactente , Gravidez , Aborto Espontâneo/epidemiologia , Estudos de Coortes , Doenças Fetais , Coração Fetal/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/epidemiologia , Incidência , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia Pré-Natal
2.
Proc Natl Acad Sci U S A ; 116(9): 3919-3928, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808769

RESUMO

Ebola virus disease (EVD) often leads to severe and fatal outcomes in humans with early supportive care increasing the chances of survival. Profiling the human plasma lipidome provides insight into critical illness as well as diseased states, as lipids have essential roles as membrane structural components, signaling molecules, and energy sources. Here we show that the plasma lipidomes of EVD survivors and fatalities from Sierra Leone, infected during the 2014-2016 Ebola virus outbreak, were profoundly altered. Focusing on how lipids are associated in human plasma, while factoring in the state of critical illness, we found that lipidome changes were related to EVD outcome and could identify states of disease and recovery. Specific changes in the lipidome suggested contributions from extracellular vesicles, viremia, liver dysfunction, apoptosis, autophagy, and general critical illness, and we identified possible targets for therapies enhancing EVD survival.


Assuntos
Estado Terminal/epidemiologia , Doença pelo Vírus Ebola/genética , Metabolismo dos Lipídeos/genética , Lipídeos/genética , Adolescente , Adulto , Criança , Surtos de Doenças , Ebolavirus/genética , Ebolavirus/patogenicidade , Feminino , Regulação da Expressão Gênica/genética , Doença pelo Vírus Ebola/sangue , Doença pelo Vírus Ebola/patologia , Doença pelo Vírus Ebola/virologia , Humanos , Lipídeos/sangue , Masculino , Serra Leoa/epidemiologia , Adulto Jovem
3.
Hum Reprod ; 36(5): 1405-1415, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33421071

RESUMO

STUDY QUESTION: Is cannabis use assessed via urinary metabolites and self-report during preconception associated with fecundability, live birth and pregnancy loss? SUMMARY ANSWER: Preconception cannabis use was associated with reduced fecundability among women with a history of pregnancy loss attempting pregnancy despite an increased frequency of intercourse. WHAT IS KNOWN ALREADY: Cannabis use continues to rise despite limited evidence of safety during critical windows of pregnancy establishment. While existing studies suggest that self-reported cannabis use is not associated with fecundability, self-report may not be reliable. STUDY DESIGN, SIZE, DURATION: A prospective cohort study was carried out including 1228 women followed for up to six cycles while attempting pregnancy (2006 to 2012), and throughout pregnancy if they conceived. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women aged 18-40 years with a history of pregnancy loss (n = 1228) were recruited from four clinical centers. Women self-reported preconception cannabis use at baseline and urinary tetrahydrocannabinol metabolites were measured throughout preconception and early pregnancy (up to four times during the study: at baseline, after 6 months of follow-up or at the beginning of the conception cycle, and weeks 4 and 8 of pregnancy). Time to hCG-detected pregnancy, and incidence of live birth and pregnancy loss were prospectively assessed. Fecundability odds ratios (FOR) and 95% CI were estimated using discrete time Cox proportional hazards models, and risk ratios (RRs) and 95% CI using log-binomial regression adjusting for age, race, BMI, education level, baseline urine cotinine, alcohol use and antidepressant use. MAIN RESULTS AND THE ROLE OF CHANCE: Preconception cannabis use was 5% (62/1228), based on combined urinary metabolite measurements and self-report, and 1.3% (11/789) used cannabis during the first 8 weeks of gestation based on urinary metabolites only. Women with preconception cannabis use had reduced fecundability (FOR 0.59; 95% CI 0.38, 0.92). Preconception cannabis use was also associated with increased frequency of intercourse per cycle (9.4 ± 7 versus 7.5 ± 7 days; P = 0.02) and higher LH (percentage change 64%, 95% CI 3, 161) and higher LH:FSH ratio (percentage change 39%, 95% CI 7, 81). There were also suggestive, though imprecise, associations with anovulation (RR 1.92, 95% CI 0.88, 4.18), and live birth (42% (19/45) cannabis users versus 55% (578/1043) nonusers; RR 0.80, 95% CI 0.57, 1.12). No associations were observed between preconception cannabis use and pregnancy loss (RR 0.81, 95% CI 0.46, 1.42). Similar results were observed after additional adjustment for parity, income, employment status and stress. We were unable to estimate associations between cannabis use during early pregnancy and pregnancy loss due to limited sample size. LIMITATIONS, REASONS FOR CAUTION: Owing to the relatively few cannabis users in our study, we had limited ability to make conclusions regarding live birth and pregnancy loss, and were unable to account for male partner use. While results were similar after excluding smokers, alcohol use and any drug use in the past year, some residual confounding may persist due to these potential co-exposures. WIDER IMPLICATIONS OF THE FINDINGS: These findings highlight potential risks on fecundability among women attempting pregnancy with a history of pregnancy loss and the need for expanded evidence regarding the reproductive health effects of cannabis use in the current climate of increasing legalization. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland (Contract numbers: HHSN267200603423, HHSN267200603424, HHSN267200603426, HHSN275201300023I). Jeannie G. Radoc has been funded by the National Institutes of Health Medical Research Scholars Program, a public-private partnership supported jointly by the National Institutes of Health and generous contributions to the Foundation for the National Institutes of Health from the Doris Duke Charitable Foundation (DDCF Grant # 2014194), Genentech, Elsevier, and other private donors. The authors report no conflict of interest in this work and have nothing to disclose. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov NCT00467363.


Assuntos
Aborto Espontâneo , Cannabis , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Adolescente , Adulto , Cannabis/efeitos adversos , Criança , Feminino , Fertilidade , Humanos , Nascido Vivo , Masculino , Gravidez , Estudos Prospectivos , Adulto Jovem
4.
BJOG ; 126(12): 1491-1497, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31334907

RESUMO

OBJECTIVE: To evaluate the association between marijuana use and a composite adverse pregnancy outcome using biological sampling. DESIGN: Retrospective cohort study. SETTING: Single tertiary center. POPULATION: Young women (13-22 years old) with singleton, non-anomalous pregnancies delivered from September 2011 to May 2017. METHODS: Exposure was defined as marijuana detected on universal urine toxicology testing or by self-report. Multivariable logistic regression modelling was used to estimate the effect of any marijuana use on the primary composite outcome. The effect of marijuana exposure was also estimated for self-reported use, toxicology-detected use, and multiple use detected by toxicology. MAIN OUTCOME MEASURE: The primary composite outcome included spontaneous preterm birth, hypertensive disorders of pregnancy, stillbirth, or small for gestational age. RESULTS: Of 1206 pregnant young women, 17.5% (n = 211) used marijuana. Among the women who used marijuana, 8.5% (n = 18) were identified by self-report alone, 63% (n = 133) by urine toxicology alone, and 28.4% (n = 60) by both. Urine toxicology testing results were available for 1092 (90.5%) births. The composite outcome occurred more frequently in pregnancies exposed to marijuana (46 versus 34%, P < 0.001). This remained significant after adjusting for race/ethnicity and tobacco in the multivariable model (adjusted OR 1.50, 95% CI 1.09-2.05). When marijuana exposure was defined by self-report only, the association with adverse pregnancy outcome became non-significant (adjusted OR 1.01, 95% CI 0.62-1.64). CONCLUSION: In a population of young women with nearly universal biological sampling, marijuana exposure was associated with adverse pregnancy outcomes. The heterogeneity of findings in existing studies evaluating the impact of marijuana on mothers and neonates may result from the incomplete ascertainment of exposure. TWEETABLE ABSTRACT: Marijuana use, as detected by universal urine testing, was associated with a composite adverse pregnancy outcome among young mothers.


Assuntos
Uso da Maconha/efeitos adversos , Mães , Complicações na Gravidez/epidemiologia , Assunção de Riscos , Adolescente , Estudos de Coortes , Colorado/epidemiologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Modelos Logísticos , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/urina , Resultado da Gravidez , Cuidado Pré-Natal , Estudos Retrospectivos , Adulto Jovem
7.
Ultrasound Obstet Gynecol ; 44(1): 50-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24357432

RESUMO

OBJECTIVE: The economic implications of strategies to improve prenatal screening for congenital heart disease (CHD) in low-risk mothers have not been explored. The aim was to perform a cost-effectiveness analysis of different screening methods. METHODS: We constructed a decision analytic model of CHD prenatal screening strategies (four-chamber screen (4C), 4C + outflow, nuchal translucency (NT) or fetal echocardiography) populated with probabilities from the literature. The model included whether initial screens were interpreted by a maternal-fetal medicine (MFM) specialist and different referral strategies if they were read by a non-MFM specialist. The primary outcome was the incremental cost per defect detected. Costs were obtained from Medicare National Fee estimates. A probabilistic sensitivity analysis was undertaken on model variables commensurate with their degree of uncertainty. RESULTS: In base-case analysis, 4C + outflow referred to an MFM specialist was the least costly strategy per defect detected. The 4C screen and the NT screen were dominated by other strategies (i.e. were more costly and less effective). Fetal echocardiography was the most effective, but most costly. On simulation of 10 000 low-risk pregnancies, 4C + outflow screen referred to an MFM specialist remained the least costly per defect detected. For an additional $580 per defect detected, referral to cardiology after a 4C + outflow was the most cost-effective for the majority of iterations, increasing CHD detection by 13 percentage points. CONCLUSIONS: The addition of examination of the outflow tracts to second-trimester ultrasound increases detection of CHD in the most cost-effective manner. Strategies to improve outflow-tract imaging and to refer with the most efficiency may be the best way to improve detection at a population level.


Assuntos
Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Custos de Cuidados de Saúde/estatística & dados numéricos , Cardiopatias Congênitas/diagnóstico por imagem , Ultrassonografia Pré-Natal/economia , Ecocardiografia/economia , Feminino , Cardiopatias Congênitas/economia , Humanos , Método de Monte Carlo , Medição da Translucência Nucal/economia , Gravidez , Segundo Trimestre da Gravidez , Sensibilidade e Especificidade , Ultrassonografia Doppler/economia , Ultrassonografia Pré-Natal/métodos , Estados Unidos
8.
Ann Dermatol Venereol ; 141(2): 94-105, 2014 Feb.
Artigo em Francês | MEDLINE | ID: mdl-24507203

RESUMO

BACKGROUND: Superficial acral fibromyxoma (SAFM) is a benign soft tissue tumor located in the acral areas, particularly the peri- and sub-ungueal areas. Sub-matricial localisations have not been reported to date. PATIENTS AND METHODS: We report herein the clinical and pathological presentation of three cases of SAFM located solely under the matrix. The patients presented with pseudo-clubbing, onychogryphosis or triangular macrolunula. The histopathological appearance was characteristic. DISCUSSION: SAFM is a slow-growing, skin-colored, firm nodule, located chiefly on the digits or the toes, and especially in the nail area. It may or may not be painful. Microscopically, it presents as a relatively well-circumscribed but unencapsulated dermal tumor, composed of spindle shaped cells integrated in a myxocollagenic matrix, sometimes invading the subcutis. Tumor cells diffusely express CD34. A conservative surgical approach is recommended. Both clinicians and pathologists should be aware of this entity in order to avoid misdiagnosis, which can lead to unwarranted mutilating surgery. CONCLUSION: Sub-matricial localisation of SAFM is extremely rare and may present as pseudo-clubbing, isolated onychogryphosis or a triangular macrolunula. A conservative surgical approach should be recommended.


Assuntos
Fibroma/diagnóstico , Doenças da Unha/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adulto , Antígenos CD34 , Biomarcadores Tumorais , Diagnóstico Diferencial , Feminino , Fibroma/patologia , Fibroma/cirurgia , Dedos , Humanos , Lipoma/diagnóstico , Masculino , Pessoa de Meia-Idade , Doenças da Unha/patologia , Doenças da Unha/cirurgia , Neurilemoma/diagnóstico , Osteoartropatia Hipertrófica Secundária/etiologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Dedos do Pé
9.
Sci Rep ; 12(1): 1223, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075161

RESUMO

Being able to estimate and predict future microplastic distributions in the environment is one of the major challenges of the rapidly developing field of microplastic research. However, this task can only be achieved if our understanding of the decay of individual microplastic particles is significantly enhanced. Here, we show by using a rate equation model that currently available data of size distributions measured at single times cannot provide useful insights into this process. To analyze what data contains more information we generated more complex artificial data mimicking subsequent measurements using a stochastic simulation algorithm. Applying our model to this data revealed the following minimal requirements for future experimental data: (1) data should be collected as time series at identical spots and (2) size measurements should be combined with mass measurements. In contrast to currently available data, flux rates and decay parameters of individual particles can be extracted from such data.

10.
Science ; 373(6556): 797-801, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34385397

RESUMO

An unconventional superconducting state was recently discovered in uranium ditelluride (UTe2), in which spin-triplet superconductivity emerges from the paramagnetic normal state of a heavy-fermion material. The coexistence of magnetic fluctuations and superconductivity, together with the crystal structure of this material, suggests that a distinctive set of symmetries, magnetic properties, and topology underlie the superconducting state. Here, we report observations of a nonzero polar Kerr effect and of two transitions in the specific heat upon entering the superconducting state, which together suggest that the superconductivity in UTe2 is characterized by a two-component order parameter that breaks time-reversal symmetry. These data place constraints on the symmetries of the order parameter and inform the discussion on the presence of topological superconductivity in UTe2.

11.
Mar Pollut Bull ; 157: 111330, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658694

RESUMO

Inconsistencies in microplastic quantification are a problem in current microplastic research, leading to difficulties in inter-study comparability. This study proposes a guideline for consistent quantification of microplastic distributions. It contains specific recommendations on how to quantify common microplastic particle parameters, such as size or shape. These recommendations are based on how reliably a parameter can be measured and its importance for inter-study comparability. Furthermore, our study proposes a multidimensional vector approach, where one vector contains the information for the microplastic distribution in one sample. In this way geometric and statistical means can be used to quantitatively compare different studies. In particular, in combination with our proposed quantification procedure, a meaningful comparison of microplastic distributions across different studies becomes possible. Ultimately, this allows comparable long-term and global scale assessments, as well as the development of modeling approaches.


Assuntos
Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Microplásticos
12.
Clin Biochem ; 66: 100-102, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30753843

RESUMO

OBJECTIVES: Elevated levels of metabolites such as ammonia and propionylcarnitine in propionic acidemia (PA) lead to an increased reactive oxygen species (ROS) production which could activate and stabilize the epigenetic regulated hypoxia-inducible factor-1α (HIF-1α). In order to evaluate the DNA methylation status of the HIF-1α binding site in PA, we investigated the antioxidant gluthatione peroxidase 3 gene (GPX3) promoter region. DESIGN AND METHODS: Using leukocyte DNA extracted from bloodspots collected 2-4 days after birth from diet free newborns, the cytosine phosphodiester bond guanine (CpG) dinucleotides of a HIF-1α binding site (CGTTTTTTACG) in the promoter region of GPX3 was retrospectively analysed. Patients included 7 PA. and 7 healthy controls (KO) respectively. RESULTS: A demethylated TGTTTTTTATG allele was detected in 3 PA patients with blood ammonia (NH3) concentrations of 500, 595, and 987 umol/L respectively; a demethylated/partial methylated TGTTTTTTAC/TG allele in 4 PA patients (2 PA with blood NH3 = 213, 271 umol/L respectively); a partial methylated C/TGTTTTTTAC/TG allele in 5 healthy controls respectively; a partial methylated/methylated C/TGTTTTTTACG allele in 2 healthy controls. CONCLUSION: Our results suggest that at excess NH3, the DNA methylation status of the HIF-1α binding site of GPX3 in newborns with PA is demethylated (TGTTTTTTATG allele). However, the demethylated allele has to be confirmed as a statistically significant change in more patients.


Assuntos
Amônia/metabolismo , Metilação de DNA/fisiologia , Glutationa Peroxidase/genética , Hiperamonemia/fisiopatologia , Acidemia Propiônica/fisiopatologia , Sítios de Ligação/fisiologia , Desmetilação , Humanos , Recém-Nascido , Regiões Promotoras Genéticas/fisiologia
14.
Nat Biotechnol ; 18(3): 339-42, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700153

RESUMO

Several important crops have been engineered to express toxins of Bacillus thuringiensis (Bt) for insect control. In 1999, US farmers planted nearly 8 million hectares (nearly 20 million acres) of transgenic Bt crops approved by the EPA. Bt-transgenic plants can greatly reduce the use of broader spectrum insecticides, but insect resistance may hinder this technology. Present resistance management strategies rely on a "refuge" composed of non-Bt plants to conserve susceptible alleles. We have used Bt-transgenic broccoli plants and the diamondback moth as a model system to examine resistance management strategies. The higher number of larvae on refuge plants in our field tests indicate that a "separate refuge" will be more effective at conserving susceptible larvae than a "mixed refuge" and would thereby reduce the number of homozygous resistant (RR) offspring. Our field tests also examined the strategy of spraying the refuge to prevent economic loss to the crop while maintaining susceptible alleles in the population. Results indicate that great care must be taken to ensure that refuges, particularly those sprayed with efficacious insecticides, produce adequate numbers of susceptible alleles. Each insect/Bt crop system may have unique management requirements because of the biology of the insect, but our studies validate the need for a refuge. As we learn more about how to refine our present resistance management strategies, it is important to also develop the next generation of technology and implementation strategies.


Assuntos
Bacillus thuringiensis/genética , Imunidade Inata/genética , Plantas Comestíveis/genética , Plantas Geneticamente Modificadas/genética , Animais , Bacillus thuringiensis/metabolismo , Biotecnologia , Brassica/genética , Mariposas/genética , Fatores de Tempo
15.
J Perinatol ; 36(8): 601-5, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27054838

RESUMO

OBJECTIVE: The objective of the study is to evaluate low-dose aspirin (LDA) for pre-eclampsia prevention in twin gestations with elevated maternal serum human chorionic gonadotropin (hCG). STUDY DESIGN: Secondary analysis of the Maternal-Fetal Medicine Units High-Risk Aspirin trial for pre-eclampsia prevention. A threshold hCG level for predicting pre-eclampsia was identified in placebo-randomized patients. Pre-eclampsia incidence and time of onset were compared between treatment groups, overall and by hCG threshold category. RESULTS: Pre-eclampsia incidence was lower with LDA than with placebo (6% vs 16%, OR 0.32, 95% CI 0.12 to 0.82). An hCG threshold of 29.96 IU ml(-1) best predicted pre-eclampsia. In patients with hCG <29.96 IU ml(-1), the differences in pre-eclampsia incidence or time of onset were not significant. In patients with hCG >29.96 IU ml(-1), LDA was associated with lower pre-eclampsia incidence than placebo (6% vs 23%, OR 0.21, 95% CI 0.06 to 0.79) and delayed onset. CONCLUSION: Twin gestations with elevated hCG levels may benefit from LDA for pre-eclampsia prevention.


Assuntos
Aspirina/administração & dosagem , Gonadotropina Coriônica/sangue , Pré-Eclâmpsia/prevenção & controle , Complicações na Gravidez/prevenção & controle , Adulto , Método Duplo-Cego , Feminino , Humanos , Pré-Eclâmpsia/sangue , Gravidez , Complicações na Gravidez/sangue , Gravidez de Gêmeos , Cuidado Pré-Natal , Curva ROC , Estados Unidos , Adulto Jovem
16.
Oncogene ; 7(3): 597-605, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1347919

RESUMO

The nuclear oncogenes v-erbA and v-ets are known to cooperate with other viral oncogenes in the induction of avian erythroleukemia. Thus, in the case of avian erythroblastosis virus (AEV), v-erbA enhances the effect of the tyrosine kinase-encoding v-erbB oncogene by blocking the terminal differentiation of erythroid cells. In the case of E26 virus a fusion of the product from v-ets to that of the nuclear oncogene v-myb is a prerequisite for leukemogenicity. Here we show that an artificial virus carrying both v-erbA and v-ets induces a rapid, acute erythroleukemia phenotypically similar to that induced by AEV. In contrast, virus constructs containing either v-erbA or v-ets alone are non-leukemogenic, although they are capable of transforming erythroid cells in vitro. Analysis of in vitro-transformed cells showed that v-erbA induces a block of differentiation without abrogating dependence on anemic serum, while v-ets predominantly causes anemic serum independence. As expected, cells transformed by both oncogenes exhibit an increased proliferative potential, are blocked in differentiation and are anemic serum independent. These data demonstrate that two separately expressed nuclear oncoproteins can complement each other in vitro and in vivo. They also show that the v-Ets protein on its own can contribute to leukemogenesis.


Assuntos
Transformação Celular Neoplásica/genética , Leucemia Eritroblástica Aguda/genética , Proteínas Nucleares/fisiologia , Oncogenes , Proteínas Oncogênicas de Retroviridae/fisiologia , Animais , Células da Medula Óssea , Divisão Celular , Transformação Celular Viral , Embrião de Galinha , Galinhas , Expressão Gênica , Leucemia Experimental/genética , Proteínas Oncogênicas v-erbA , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-myb
17.
J Psychiatr Res ; 36(3): 119-29, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11886689

RESUMO

Antidepressants are widely used for the treatment of psychiatric disorders, including depression and anxiety. Although they are efficient drugs, there are several unsolved questions regarding their clinical pharmacology. Furthermore, the molecular mechanisms of action of antidepressants are still poorly understood and the molecular targets and pathways remain to be identified. To address these issues, we performed a gene expression analysis in mice treated with two commonly used antidepressants with differing pharmacology (paroxetine or mirtazapine) for 1, 7 or 28 days. We quantified the effects of these treatments on gene expression in the mouse brain with cDNA-microarrays containing 3624 expressed sequence tags (ESTs) representing murine genes expressed in the brain. We found that both drugs led to downregulation of four common genes. In addition, although it was possible to identify common targets for the two drugs, the expression profiles of the drugs differed in a fundamental manner, and the longer the treatment duration, the greater the difference in the profiles. These findings suggest that antidepressants with different pharmacologies can share molecular targets even though the primary pathways at which they act are different.


Assuntos
Antidepressivos de Segunda Geração/farmacologia , Antidepressivos Tricíclicos/farmacologia , Perfilação da Expressão Gênica , Mianserina/análogos & derivados , Mianserina/farmacologia , Paroxetina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , DNA Complementar , Regulação para Baixo , Esquema de Medicação , Masculino , Camundongos , Mirtazapina , Análise de Sequência com Séries de Oligonucleotídeos
18.
Pharmacol Biochem Behav ; 34(4): 681-4, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2516325

RESUMO

In this study we determined if endogenous opioid peptides may contribute to the depression of ventilation seen in dystrophic hamsters. Ventilation of control and dystrophic awake hamsters was determined prior to either naloxone (1 mg/kg) or saline administration and then 5, 15 and 30 minutes postinjection. Subsequently, animals were exposed to a hypercapnic challenge (7% CO2 in O2). Control hamsters increased ventilation significantly (p less than 0.01) after naloxone compared to saline treatment. In contrast, dystrophic hamsters showed no difference in ventilation when they received either naloxone or saline. Both groups increased ventilation significantly (p less than 0.05) after hypercapnic challenge, whether they had received naloxone or saline. Although dystrophic hamsters can respond to a ventilatory stimulant (CO2), naloxone did not increase ventilation, possibly indicating that endogenous opioids are not responsible for their depressed ventilation.


Assuntos
Distrofia Muscular Animal/fisiopatologia , Naloxona/farmacologia , Mecânica Respiratória/efeitos dos fármacos , Animais , Dióxido de Carbono , Cricetinae , Modelos Animais de Doenças , Endorfinas/fisiologia , Masculino , Mesocricetus
19.
J Econ Entomol ; 94(1): 240-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11233120

RESUMO

Experimental evaluation of the effectiveness of resistance management tactics is vital to help provide guidelines for the deployment of transgenic insecticidal crops. Transgenic broccoli expressing a Cry1Ac gene of Bacillus thuringiensis (Bt) and the diamondback moth, Plutella xylostella (L.), were used in greenhouse tests to evaluate the influence of size and placement of nontransgenic refuge plants on changes in resistance allele frequency and pest population growth. In the first test with an initial Cry1Ac-resistance (R) allele frequency of 0.007, P. xylostella were introduced into cages with the following treatments: 0, 3.3, 10, 20, and 100% refuge plants. Results after four generations showed that resistance could be delayed by increasing the proportion of refuge plants in the cage. Population growth was also influenced by refuge size with the highest populations occurring in treatments that had either no refuge plants or all refuge plants. In the second test, we evaluated the effect of refuge placement by comparing 20% separate and 20% mixed refuges. P. xylostella with an initial frequency of resistant alleles at 0.0125 were introduced into cages and allowed to cycle; later generations were evaluated for resistance and population growth. Separating the refuge had a pronounced effect on delaying resistance and slowing establishment of resistant larvae on Bt plants. Combining information from both trials, we found a strong negative correlation between the number of larvae on Bt plants and the mortality of the population in leaf dip bioassays. Results from larval movement studies showed that separate refuges delayed resistance better than mixed refuges because they conserved relatively more susceptible alleles than R alleles and did not increase the effective dominance of resistance.


Assuntos
Bacillus thuringiensis , Proteínas de Bactérias , Toxinas Bacterianas , Brassica , Endotoxinas , Mariposas , Controle Biológico de Vetores , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Comportamento Animal , Brassica/genética , Endotoxinas/genética , Proteínas Hemolisinas , Resistência a Inseticidas , Masculino , Controle Biológico de Vetores/métodos , Plantas Geneticamente Modificadas
20.
Ann Pathol ; 15(1): 38-44, 1995.
Artigo em Francês | MEDLINE | ID: mdl-7702666

RESUMO

Sixty two patients fulfilling the definition established by the Centers for Disease Control in 1982 for persistent lymphadenopathy syndrome, thought to be related to the human immunodeficiency virus (HIV) infection, were selected at the Butare university hospital, in Rwanda, between 1987 and 1988. Forty-five (73%) of them were indeed seropositive. Fifteen patients of sixty two (24%) presented unexpectedly evidence of tuberculous adenitis on biopsy. Three of them, found HIV-1 seronegative, showed a classical follicular adenitis, whereas the twelve other seropositive patients presented unusual histologic features, consisting of more or less immature tuberculoid granulomas with an abundant caseating and often granular necrosis, containing acid fast bacilli. Numerous blood vessels and abundant plasmacytosis were found in non-necrotic areas. Semi-quantitative evaluation of the granulomatous reaction components provided a histological spectrum probably related to the degree of impairment of the cellular immune response, which could be of prognostic significance. In areas where populations are exposed to both HIV and M. tuberculosis, it appears that lymph node biopsy with mycobacterial culture should be recommended in order to detect occult tuberculosis among HIV-seropositive persons, allowing accurate medical care and adequate public health surveillance.


PIP: During 1987-1988 in Burundi, 62 patients presented at Butare University Hospital with chronic lymphadenopathy syndrome. Physicians suspected that the syndrome was a result of HIV infection. 45 (73%) were indeed HIV seropositive. The biopsy of the lymph nodes revealed that 15 of the 62 patients (24%) had histologic characteristics of tuberculosis (TB). 12 of the patients with lymph node TB were HIV seropositive. The other three cases exhibited classical signs of follicular adenitis. All the HIV positive cases with lymph node TB had many enlarged lymph nodes which were superficial, easily palpated, and moveable. They also had little mass. Specifically, they had rather immature granulomas with considerable necrosis which turns the tissue into a dry mass resembling cheese, and, sometimes, granular necrosis. These granulomas had acid fast bacilli. The non-necrotic areas had many blood vessels and considerable excess of plasma cells in the blood. Thus, the lymph nodes of the HIV positive TB cases were different than those of the 3 HIV negative cases. The semi-quantitative evaluation of the components of the granulomatous TB reaction allowed the researchers to rank the lesions in a manner probably parallel to the degree of deterioration of the cellular immune response. This semi-quantitative evaluation could constitute a prognostic value. Lymph node biopsy and mycobacterial culture appear then to be indicated among HIV seropositive persons living where there is a joint HIV-1/TB endemic. This allows clinicians to detect concealed TB among HIV seropositive individuals and to introduce as fast as possible an adequate anti-TB treatment and to enable a fight against the progression of the illness and its propagation in a group of sick persons.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/imunologia , Soropositividade para HIV/patologia , HIV-1/imunologia , Tuberculose dos Linfonodos/imunologia , Infecções Oportunistas Relacionadas com a AIDS/patologia , Adolescente , Adulto , Biópsia , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ruanda , Tuberculose dos Linfonodos/patologia
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