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1.
Gesundheitswesen ; 86(1): 18-27, 2024 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-38081207

RESUMO

INTRODUCTION: Unplanned out-of-hospital births are very rare in the ambulance service and there is evidence that emergency paramedics do not feel comfortable with this operational picture. At the same time, there is an increased of morbidity and mortality for both the mother and the newborn. The aims of the present cross-sectional study were to identify insecurities of emergency paramedics in connection with unplanned out-of-hospital births, to analyse the reasons for this and to derive possible support measures to be implemented. MATERIAL AND METHODS: This study is a quantitative cross-sectional study examining management of unplanned out-of-hospital births by paramedics using a self-designed questionnaire. 65 participants took part in the online survey during the period from April 6, 2022 to April 30, 2022. SPSS was used for statistical data analysis. The central tendency of various influencing variables was examined with the help of the Mann-Whitney U test, the significance level was α<0.05. RESULTS: On average, preparation Median (IQR): 2.0 (1.0) and safety with the measures to be performed 3.0 (01.0), as well as knowledge about unplanned out-of-hospital births 2.0 (1.0) were rated moderately well. The participating paramedics had particular difficulties with the documentation of the birth process 3.0 (1.0). There was a great deal of respect for out-of-hospital birth attendance among participants 1.0 (1.0). Participation in an interdisciplinary simulation session appeared to have had a positive influence on the handling and preparation for safety in the measures to be taken (p=0.016). CONCLUSION: Insecurites as well as possible reasons for them could be identified. Possible suggestions for improvement for emergency paramedics in unplanned out-of-hospital births were developed. For example, specific birth protocols and participation in a simulation are good ways to help.


Assuntos
Serviços Médicos de Emergência , Paramédico , Recém-Nascido , Feminino , Humanos , Estudos Transversais , Alemanha/epidemiologia , Inquéritos e Questionários , Hospitais
2.
BMC Pregnancy Childbirth ; 22(1): 214, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35300616

RESUMO

BACKGROUND: Optimal mode of birth for twins, in particular monochorionic twins, has been the subject of much debate. This retrospective study compared maternal and newborn outcomes after vaginal birth in monochorionic and dichorionic twins, utilizing a large institutional database. METHODS: Retrospective analysis focusing on 98 monochorionic-diamniotic (MC-DA) and 540 dichorionic-diamniotic (DC-DA) twin births extracted from the perinatal database of a large German hospital. Pregnancies ≥36 weeks of gestation with two viable foetuses born between 2004 and 2014 divided into planned vaginal and planned caesarean delivery were included. Descriptive analysis was performed for maternal characteristics. Odds ratios (OR) with 95% confidences intervals (CI) tested the predictive effect of vaginal birth on neonatal and maternal outcomes. RESULTS: 51.0% MC-DA and 46.7% DC-DA twin pregnancies were planned vaginal births and 44.0% MC-DA mothers and 43.7% DC-DA mothers actually gave birth vaginally. The overall rate of caesarean section (CS) during the years under observation was 79.6% for MC-DA and 77.0% for DC-DA pregnancies. There were no significant differences in neonatal outcome between the subsamples, although acidosis was observed more often in the second DC-DA twin and Apgar scores < 7 were observed more often in MC-DA twins. CONCLUSION: Vaginal birth may be recommended as an option to women with monochorionic twins as no significant differences in outcomes were found between MC-DA and DC-DA twins. However, over half of planned vaginal twin births resulted in CS.


Assuntos
Parto Obstétrico/métodos , Gravidez de Gêmeos , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Índice de Apgar , Parto Obstétrico/estatística & dados numéricos , Feminino , Alemanha , Humanos , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Centros de Atenção Terciária
3.
Z Gastroenterol ; 60(7): 1111-1117, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34781388

RESUMO

PURPOSE: Budd-Chiari syndrome (BCS) is a rare disease characterized by hepatic venous outflow tract obstruction. The study aimed to evaluate the diagnostic utility of ultrasound in confirming the diagnosis of BCS and to provide an overview of the clinical picture. MATERIALS AND METHOD: In this retrospective single-center study, patients with an initial diagnosis of BCS were included. The files were analyzed concerning the ultrasound images and compared to computed tomography (CT) and magnetic resonance imaging (MRI). Main clinical signs of BCS were collected. RESULTS: Data of 25 patients were analyzed. Doppler sonography showed the highest sensitivity (78.9%) with the highest specificity 97.4 (%) in confirming the correct diagnosis of BCS. Main imaging signs were obstruction in the hepatic veins (68.0%, 17/25 thrombotic), collaterals (91.7%, 11/12 intrahepatic), inhomogeneous liver parenchyma (7/21), and a hypertrophied lobus caudatus (18/21) (p < 0.01). All imaging signs could be detected with sonography. Hypertrophied lobus caudatus was seen exclusively in BCS. Furthermore, portal hypertension (9/25), liver cirrhosis (9/25), and ascites (19/25) can be diagnosed as non-specific signs of BCS (p < 0.01).The main clinical findings were elevated γ-GT levels in the laboratory (92.0%, 23/25, p < 0.01) and esophageal varices in endoscopy (12/25 p < 0.01). An association with myeloproliferative neoplasia (MPN) was frequently seen (10/25) (p < 0.01). CONCLUSION: The present study demonstrates that sonography is an appropriate tool for the diagnosis of BCS and should be used as the first imaging procedure.


Assuntos
Síndrome de Budd-Chiari , Síndrome de Budd-Chiari/diagnóstico por imagem , Síndrome de Budd-Chiari/patologia , Veias Hepáticas/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Ultrassonografia , Veia Cava Inferior/patologia
4.
Cell Commun Signal ; 19(1): 44, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33832488

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent and represents a growing challenge in terms of prevention and treatment. A minority of affected patients develops inflammation, subsequently fibrosis, cirrhosis and hepatocellular carcinoma (HCC). HCC is a leading cause of cancer-related death. An increased number of senescent cells correlate with age-related tissue degeneration during NAFLD-induced HCC. Senolytics are promising agents that target selectively senescent cells. Previous studies showed that whereas a combination of the senolytic drugs dasatinib and quercetin (D + Q) reduced NAFLD in mice, D + Q lacked efficacy in removing doxorubicin-induced ß-gal-positive senescent cells in human HCC xenografted mice. Whether D + Q has an effect on the age-associated spectrum of NAFLD-inflammation-HCC remains unknown. METHODS: Here, we utilized an established model of age- and obesity-associated HCC, the low dose diethylnitrosamine (DEN)/high fat diet (HFD), a regimen promoting liver inflammation and tumorigenesis over a long period of 9 months. Four groups of mice each were created: group 1 included control untreated mice; group 2 included mice treated with D + Q; group 3 included mice undergoing the DEN/HFD protocol; group 4 included mice undergoing the DEN/HFD protocol with the administration of D + Q. At the end of the chemical/dietary regimen, we analyzed liver damage and cell senescence by histopathology, qPCR and immunoblotting approaches. RESULTS: Unexpectedly, D + Q worsened liver disease progression in the DEN/HFD mouse model, slightly increasing histological damage and tumorigenesis, while having no effect on senescent cells removal. CONCLUSIONS: In summary, using an animal model that fully recapitulates NAFLD, we demonstrate that these compounds are ineffective against age-associated NAFLD-induced HCC. Video Abstract.


Assuntos
Envelhecimento/patologia , Dasatinibe/efeitos adversos , Progressão da Doença , Hepatopatias/patologia , Obesidade/patologia , Quercetina/efeitos adversos , Senoterapia/efeitos adversos , Envelhecimento/genética , Animais , Dieta Hiperlipídica , Dietilnitrosamina , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hepatopatias/sangue , Hepatopatias/genética , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/sangue , Obesidade/genética
5.
BMC Pediatr ; 21(1): 111, 2021 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-33676430

RESUMO

BACKGROUND: Offspring of mothers with gestational diabetes mellitus (GDM) have an increased risk of neonatal complications like birth trauma due to macrosomia or postnatal hypoglycemia, as well as long-term metabolic sequelae. Neonatal body composition may be a sensitive marker of metabolic effects on the fetus caused by suboptimal glycemic control during pregnancy. OBJECTIVE: To determine body composition in offspring of mothers with GDM compared to a reference cohort of healthy term neonates and to assess whether increased body fat would be associated with postnatal hypoglycemia. METHODS: This prospective, observational, cross-sectional study included 311 full-term, singleton infants born between June 2014 and July 2015. Body composition was measured within 96 h of birth using air displacement plethysmography. Results are indicated as median (1st Quartile - 3rd Quartile). RESULTS: Of 311 infants, 40 (12.9%) were born to mothers with GDM. Birth weight standard deviation scores (SDS) (0.24 vs. - 0.07, p = 0.04), fat mass (370 g vs. 333 g, p = 0.02) as well as fat mass/total body mass (BF%; 11.4% vs. 10.8%, p = 0.03) were significantly higher in infants following maternal GDM than in controls. In GDM offspring, anthropometric parameters, fat mass or BF% did not differ between infants with or without postnatal hypoglycemia. In this cohort, SDS for birth weight, fat mass, fat free mass, BF% or postnatal hypoglycemia were not associated with maternal blood glucose levels measured at an oral glucose tolerance test. CONCLUSIONS: SDS for birth weight, neonatal fat mass, and BF% were significantly higher in newborns following maternal GDM. In these infants born to mothers with GDM, body composition did not differ between those with or without postnatal hypoglycemia.


Assuntos
Diabetes Gestacional , Hipoglicemia , Peso ao Nascer , Composição Corporal , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Hipoglicemia/diagnóstico , Hipoglicemia/etiologia , Lactente , Recém-Nascido , Gravidez , Estudos Prospectivos
6.
Int J Mol Sci ; 22(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923652

RESUMO

Studies over the past 30 years have revealed that adipose tissue is the major endocrine and paracrine organ of the human body. Arguably, adiopobiology has taken its reasonable place in studying obesity and related cardiometabolic diseases (CMDs), including Alzheimer's disease (AD), which is viewed herein as a neurometabolic disorder. The pathogenesis and therapy of these diseases are multiplex at basic, clinical and translational levels. Our present goal is to describe new developments in cardiometabolic and neurometabolic adipobiology. Accordingly, we focus on adipose- and/or skeletal muscle-derived signaling proteins (adipsin, adiponectin, nerve growth factor, brain-derived neuroptrophic factor, neurotrophin-3, irisin, sirtuins, Klotho, neprilysin, follistatin-like protein-1, meteorin-like (metrnl), as well as growth differentiation factor 11) as examples of metabotrophic factors (MTFs) implicated in the pathogenesis and therapy of obesity and related CMDs. We argue that these pathologies are MTF-deficient diseases. In 1993 the "vascular hypothesis of AD" was published and in the present review we propose the "vasculometabolic hypothesis of AD." We discuss how MTFs could bridge CMDs and neurodegenerative diseases, such as AD. Greater insights on how to manage the MTF network would provide benefits to the quality of human life.


Assuntos
Adipocinas/metabolismo , Síndrome Metabólica/metabolismo , Doenças Neurodegenerativas/metabolismo , Animais , Humanos , Síndrome Metabólica/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Fatores de Crescimento Neural/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Neuropeptídeos/metabolismo , Transdução de Sinais
7.
Ultraschall Med ; 41(3): 308-316, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31026863

RESUMO

PURPOSE: The aim of the current study was to evaluate point of care ultrasound (POCUS) in geriatric patients by echoscopy using a handheld ultrasound device (HHUSD, VScan) at bedside in comparison to a high-end ultrasound system (HEUS) as the gold standard. MATERIALS AND METHODS: Prospective observational study with a total of 112 geriatric patients. The ultrasound examinations were independently performed by two experienced blinded examiners with a portable handheld device and a high-end ultrasound device. The findings were compared with respect to diagnostic findings and therapeutic implications. RESULTS: The main indications for the ultrasound examinations were dyspnea (44.6 %), fall (frailty) (24.1 %) and fever (21.4 %). The most frequently found diagnoses were cystic lesions 32.1 % (35/109), hepatic vein congestion 19.3 % (21/109) and ascites 13.6 % (15/110). HHUSD delivered 13 false-negative findings in the abdomen resulting in an "overall sensitivity" of 89.5 %. The respective "overall specificity" was 99.6 % (7 false-positive diagnoses). HHUSD (versus HEUS data) resulted in 13.6 % (17.3 %) diagnostically relevant procedures in the abdomen and 0.9 % (0.9 %) in the thorax. Without HHUSD (HEUS) 95.7 % (100 %) of important pathological findings would have been missed. CONCLUSION: The small HHUSD tool improves clinical decision-making in immobile geriatric patients at the point of care (geriatric ward). In most cases, HHUSD allows sufficiently accurate yes/no diagnoses already at the bedside, thereby clarifying the leading symptoms for early clinical decision-making.


Assuntos
Abdome , Sistemas Automatizados de Assistência Junto ao Leito , Ultrassonografia , Abdome/diagnóstico por imagem , Idoso , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade
8.
Cytogenet Genome Res ; 159(2): 88-96, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31593945

RESUMO

The bush dog (Speothos venaticus, 2n = 74) is a near threatened species taxonomically classified among South American canids. We revised the bush dog karyotype and performed a comparative sequence analysis of satellite and satellite-like DNAs in 6 canids: the bush dog, domestic dog (Canis familiaris, 2n = 78), grey wolf (C. lupus, 2n = 78), Chinese raccoon dog (Nyctereutes procyonoides procyonoides, 2n = 54+B), red fox (Vulpes vulpes, 2n = 34+B), and arctic fox (V. lagopus, 2n = 48-50) to specify the species position among Canidae. Using FISH with painting and BAC probes, we found that the distribution of canid evolutionarily conserved chromosome segments in the bush dog karyotype is similar to that of the domestic dog and grey wolf. The bush dog karyotype differs by 2 acrocentric chromosome pairs formed by tandem fusions of the canine (29;34) and (26;35) orthologues. An interstitial signal of the telomeric probe was observed in the (26;35) fusion site in the bush dog indicating a recent evolutionary origin of this rearrangement. Sequences and hybridisation patterns of satellite DNAs were compared, and a phylogenetic tree of the 6 canid species was constructed which confirmed the bush dog position close to the wolf-like canids, and apart from the raccoon dog and foxes.


Assuntos
Cromossomos/genética , DNA Satélite/genética , Animais , Bandeamento Cromossômico/métodos , Cães , Evolução Molecular , Raposas/genética , Cariótipo , Cariotipagem/métodos , Filogenia , Lobos/genética
9.
BMC Pediatr ; 19(1): 488, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31830928

RESUMO

BACKGROUND: During pregnancy, a variety of factors can influence fetal growth and development. Intrauterine growth may impact on later life and health. Neonatal body composition may be a more sensitive marker for the intrauterine environment than established anthropometric parameters at birth. METHODS: To study neonatal body composition determined by air displacement plethysmography in healthy, term singletons as national reference data, and to establish factors impacting on neonatal body composition in this population. This prospective cross-sectional observational study included 271 healthy, full-term, singletons born between June 2014 and July 2015. Body composition was measured within 96 h of birth using air displacement plethysmography. RESULTS: Median (Q1, Q2) fat mass / total body mass (BF%) in German singletons was 10.8% (7.7-13.4) and fat free mass (FFM) 2843 g (2606-3099). Female infants had significantly increased BF% compared to male infants (11.2% (8.7-14.0) vs. 9.6% (7.2-12.1)). On multiple regression analysis, BF% and fat mass increased with female gender, maternal pre-pregnancy body mass index, non-smoking mother and parity, whereas FFM increased with male gender and increasing gestational age at birth. Gestational weight gain category, birth mode, and postnatal age at measurement were not associated with BF%, FFM or fat mass. CONCLUSIONS: We generated BF% and FFM centiles for healthy, term, singletons born in Germany; these are similar to those found in other European countries. Infant body composition at birth was associated with modifiable (pre-pregnancy body mass index, smoking), and given factors (gender, gestational age at birth, parity).


Assuntos
Composição Corporal , Estudos Transversais , Feminino , Alemanha , Humanos , Recém-Nascido , Masculino , Estudos Prospectivos , Valores de Referência
10.
Z Gastroenterol ; 57(6): 753-766, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30986884

RESUMO

PURPOSE: The purpose of this study was to analyze imaging findings in hepatic epithelioid hemangioendothelioma (HEHE) with a particular focus on contrast-enhanced ultrasound (CEUS). MATERIALS AND METHODS: This retrospective multicenter study included 10 patients with histologically proven HEHE from 5 European centers. All existing ultrasound images/videos were independently analyzed by 2 experienced examiners (DEGUM level III, internal medicine) using a standardized evaluation form. Patterns of contrast enhancement were correlated with computed tomography (CT), magnetic resonance imaging (MRI), and pathological findings. RESULTS: B-mode ultrasound, CEUS, CT, and MRI were performed in 90 %, 70 %, 100 %, and 90 % of patients, respectively. Multifocal HEHE could be observed in 80 % with affection of both liver lobes in 70 %. Analysis of CEUS revealed 3 characteristic patterns that correlated well with contrast patterns on CT and MRI: (a) peripheral nodular enhancement with centripetal fill-in and wash-out in the portal venous and late venous phase (PVLP), (b) rim-like arterial enhancement with wash-out in the PVLP, and (c) inversed target sign with/without wash-out in the PVLP. Wash-out in the PVLP as a sign suspicious of malignancy was observed in 6/7 patients (85.7 %). CONCLUSIONS: Knowledge of the different characteristic CEUS patterns is of importance to avoid misdiagnosis due to resemblance of patterns A and B to the much more common focal liver lesions hemangioma and intrahepatic cholangiocarcinoma. Of importance, sonographers should be aware that wash-out in the PVLP might be absent in some patients.


Assuntos
Neoplasias dos Ductos Biliares , Ductos Biliares Intra-Hepáticos , Hemangioendotelioma Epitelioide/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler em Cores/métodos , Adulto , Meios de Contraste/metabolismo , Humanos , Estudos Retrospectivos , Ultrassonografia
11.
BMC Med Educ ; 19(1): 125, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046757

RESUMO

BACKGROUND: In order to provide faculty-wide undergraduate ultrasound training in times of scarce resources, many medical faculties employ trained peer-student tutors to oversee the hands-on training. However, data to guide the training of ultrasound peer-student tutors are scarce. We conducted a prospective quasi-randomized study to assess the gain in theoretical knowledge and practical scanning skills of peer-student tutors who were trained with a course only, an internship only, or the combination of a course and an internship. METHODS: A total of 44 peer-student tutors were trained by a one-week course only (C-Group, n = 21), by an internship only (I-Group, n = 10) or by a course and an internship (CI-Group, n = 13). Prior to and after the completion of the training the peer-student tutors completed an MC-test (theoretical knowledge) and an OSCE (practical scanning skills). RESULTS: With all three education concepts, the peer-student tutors had significant and comparable gains in theoretical knowledge (C-group + 90%, I-group + 61.5%, CI-group + 114.0%) and practical scanning skills (C-group + 112.0%, I-group + 155.0% and CI-group + 123.5%), all p < 0.001. CONCLUSION: Peer-student tutors, who were trained with a course or an internship or a course and internship improved their theoretical knowledge and their practical scanning skills significantly and to a comparable degree.


Assuntos
Competência Clínica/normas , Educação de Graduação em Medicina/métodos , Avaliação Educacional/métodos , Medicina Interna/educação , Estudantes de Medicina , Ensino/normas , Ultrassonografia , Adulto , Difusão de Inovações , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Internato e Residência , Masculino , Modelos Educacionais , Grupo Associado , Estudos Prospectivos , Técnicas Psicológicas , Adulto Jovem
12.
BMC Med Educ ; 19(1): 170, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138197

RESUMO

BACKGROUND: Ultrasound is one of the most important imaging techniques in clinical medicine with unique advantages. Skills in ultrasound imaging are very usefull for physicians including novices and thus also mandated by the Task Force "National Competence-Based Learning Objectives for Undergraduate Medical Education" (NKLM) in Germany and as well as by the German Ultrasound Society (Deutsche Gesellschaft für Ultraschall in der Medizin, DEGUM). Since ultrasound is best learned hands-on in very small supervised groups, we developed and implemented a comprehensive ultrasound-curriculum for all undergraduate medical students of our faculty using a peer-teaching concept. METHODS: We used Kern's six-step model of curricular development comprising (1) problem identification and general needs assessment, (2) needs assessment of the targeted learners, (3) goals and objectives, (4) educational stategies, (5) implementation, and (6) evaluation and feedback. RESULTS: The developed curriculum covers basic ultrasound of the abdomen and the throat, eFAST (Extended Focused Assessment with Sonography for Trauma), lung-ultrasound, FEEL (Focused Echocardiography in Emergency Life Support) and compression duplex sonography of the thigh deep vein system. All 5th year medical students receive a 90 min lecture on ultrasound basics by a faculty member and then a 12.5 h hands-on course divided into three sessions with one student tutor for every 4 students. The students are provided with a script (PDF-File) that covers all the learning goals, including example images of pathologies. The student tutors are trained during a 1 week ultrasound course and a 21-day rotation through seven different ultrasound laboratories. In addition, they undergo a standardized 1.5 day didactical training. Prior to the implementation for all students, the overall course was tested on 27 volunteer students. These students rated (on a 6-point Likert scale from 1 = excellent to 6 = very poor) the satisfaction with the student tutors and the faculty members as 1.4 ± .9 (mean ± stddev) and 1.3 ± .5 respectively. CONCLUSION: A comprehensive ultrasound curriculum for all undergraduate medical students using a peer-teaching concept is feasible. Further studies are needed to evaluate in detail the learning outcomes for students and student tutors.


Assuntos
Currículo , Educação de Graduação em Medicina , Desenvolvimento de Programas , Ultrassonografia , Educação Baseada em Competências , Estudos de Viabilidade , Alemanha , Humanos , Avaliação de Programas e Projetos de Saúde
14.
Chromosoma ; 126(5): 615-631, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28101670

RESUMO

Homologous chromosomes exchange genetic information through recombination during meiosis, a process that increases genetic diversity, and is fundamental to sexual reproduction. In an attempt to shed light on the dynamics of mammalian recombination and its implications for genome organization, we have studied the recombination characteristics of 112 individuals belonging to 28 different species in the family Bovidae. In particular, we analyzed the distribution of RAD51 and MLH1 foci during the meiotic prophase I that serve, respectively, as proxies for double-strand breaks (DSBs) which form in early stages of meiosis and for crossovers. In addition, synaptonemal complex length and meiotic DNA loop size were estimated to explore how genome organization determines DSBs and crossover patterns. We show that although the number of meiotic DSBs per cell and recombination rates observed vary between individuals of the same species, these are correlated with diploid number as well as with synaptonemal complex and DNA loop sizes. Our results illustrate that genome packaging, DSB frequencies, and crossover rates tend to be correlated, while meiotic chromosomal axis length and DNA loop size are inversely correlated in mammals. Moreover, axis length, DSB frequency, and crossover frequencies all covary, suggesting that these correlations are established in the early stages of meiosis.


Assuntos
Cromossomos de Mamíferos/ultraestrutura , Meiose , Recombinação Genética , Ruminantes/genética , Complexo Sinaptonêmico/ultraestrutura , Animais , Cromossomos de Mamíferos/metabolismo , Quebras de DNA de Cadeia Dupla , Masculino , Camundongos , Proteína 1 Homóloga a MutL , Rad51 Recombinase , Ruminantes/metabolismo , Complexo Sinaptonêmico/metabolismo
15.
Cytogenet Genome Res ; 152(2): 73-80, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28723680

RESUMO

Recently, the reticulated giraffe (G. reticulata) was identified as a distinct species, which emphasized the need for intensive research in this interesting animal. To shed light on the meiotic process as a source of biodiversity, we analysed the frequency and distribution of meiotic recombination in 2 reticulated giraffe males. We used immunofluorescence detection of synaptonemal complex protein (SYCP3), meiotic double strand breaks (DSB, marked as RAD51 foci) in leptonema, and crossovers (COs, as MLH1 foci) in pachynema. The mean number of autosomal MLH1 foci per cell (27), which resulted from a single, distally located MLH1 focus observed on most chromosome arms, is one of the lowest among mammalian species analysed so far. The CO/DSB conversion ratio was 0.32. The pseudoautosomal region was localised in the Xq and Yp termini by FISH and showed an MLH1 focus in 83% of the pachytene cells. Chromatin structures corresponding to the nucleolus organiser regions were observed in the pachytene spermatocytes. The results are discussed in the context of known data on meiosis in Cetartiodactyla, depicting that the variation in CO frequency among species of this taxonomic group is mostly associated with their diploid chromosome number.


Assuntos
Girafas/genética , Meiose/genética , Recombinação Genética , Animais , Imunofluorescência , Hibridização in Situ Fluorescente , Masculino , Proteína 1 Homóloga a MutL/genética , Região Organizadora do Nucléolo/genética , Rad51 Recombinase/genética , Complexo Sinaptonêmico/genética
16.
Chromosome Res ; 24(3): 325-38, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27136937

RESUMO

The recurrent occurrence of sex-autosome translocations during mammalian evolution suggests common mechanisms enabling a precise control of meiotic synapsis, recombination and inactivation of sex chromosomes. We used immunofluorescence and FISH to study the meiotic behaviour of sex chromosomes in six species of Bovidae with evolutionary sex-autosome translocations (Tragelaphus strepsiceros, Taurotragus oryx, Tragelaphus imberbis, Tragelaphus spekii, Gazella leptoceros and Nanger dama ruficollis). The autosomal regions of fused sex chromosomes showed normal synapsis with their homologous counterparts. Synapsis in the pseudoautosomal region (PAR) leads to the formation of characteristic bivalent (in T. imberbis and T. spekii with X;BTA13/Y;BTA13), trivalent (in T. strepsiceros and T. oryx with X/Y;BTA13 and G. leptoceros with X;BTA5/Y) and quadrivalent (in N. dama ruficollis with X;BTA5/Y;BTA16) structures at pachynema. However, when compared with other mammals, the number of pachynema lacking MLH1 foci in the PAR was relatively high, especially in T. imberbis and T. spekii, species with both sex chromosomes involved in sex autosome translocations. Meiotic transcriptional inactivation of the sex-autosome translocations assessed by γH2AX staining was restricted to their gonosomal regions. Despite intraspecies differences, the evolutionary fixation of sex-autosome translocations among bovids appears to involve general mechanisms ensuring sex chromosome pairing, synapsis, recombination and inactivation.


Assuntos
Pareamento Cromossômico/genética , Segregação de Cromossomos/genética , Meiose/genética , Ruminantes/genética , Cromossomos Sexuais/genética , Translocação Genética , Animais , Coloração Cromossômica , Imunofluorescência , Hibridização in Situ Fluorescente
17.
Cytogenet Genome Res ; 150(2): 118-127, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28122375

RESUMO

Satellite DNA is a characteristic component of mammalian centromeric heterochromatin, and a comparative analysis of its evolutionary dynamics can be used for phylogenetic studies. We analysed satellite and satellite-like DNA sequences available in NCBI for 4 species of the family Canidae (red fox, Vulpes vulpes, VVU; domestic dog, Canis familiaris, CFA; arctic fox, Vulpes lagopus, VLA; raccoon dog, Nyctereutes procyonoides procyonoides, NPR) by comparative sequence analysis, which revealed 86-90% intraspecies and 76-79% interspecies similarity. Comparative fluorescence in situ hybridisation in the red fox and dog showed signals of the red fox satellite probe in canine and vulpine autosomal centromeres, on VVUY, B chromosomes, and in the distal parts of VVU9q and VVU10p which were shown to contain nucleolus organiser regions. The CFA satellite probe stained autosomal centromeres only in the dog. The CFA satellite-like DNA did not show any significant sequence similarity with the satellite DNA of any species analysed and was localised to the centromeres of 9 canine chromosome pairs. No significant heterochromatin block was detected on the B chromosomes of the red fox. Our results show extensive heterogeneity of satellite sequences among Canidae and prove close evolutionary relationships between the red and arctic fox.


Assuntos
DNA Satélite/genética , Cães/genética , Raposas/genética , Animais , Feminino , Hibridização in Situ Fluorescente , Masculino , Região Organizadora do Nucléolo/genética , Filogenia , Especificidade da Espécie
18.
Arch Gynecol Obstet ; 294(5): 937-944, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27084763

RESUMO

PURPOSE: To analyze the current proportions and characteristics of women using Internet (eHealth) and smartphone (mHealth) based sources of information during pregnancy and to investigate the influence, this information-seeking behavior has on decision-making. METHODS: A cross-sectional study was conducted at two major German university hospitals. Questionnaires covering socio-demographic data, medical data and details of Internet, and smartphone application use were administered to 220 pregnant women. Data analysis utilized descriptive statistics and multiple regression analysis. RESULTS: 50.7 % of pregnant women were online information seekers. 22.4 % used an mHealth pregnancy application. Women using eHealth information showed no specific profile, while women using mHealth applications proved to be younger, were more likely to be in their first pregnancy, felt less healthy, and were more likely to be influenced by the retrieved information. Stepwise backward regression analysis explained 25.8 % of the variance of mHealth use. 80.5 % of cases were classified correctly by the identified predictors. All types of Web-based information correlated significantly with decision-making during pregnancy. CONCLUSIONS: Pregnant women frequently use the Internet and smartphone applications as a source of information. While Web usage was a common phenomenon, this study revealed specific characteristics of mHealth users during pregnancy. Improved, medically accurate smartphone applications might provide a way to specifically target the mHealth user group. As user influenceability was of major relevance to all types of information, all medical content should be carefully reviewed by a multidisciplinary board of medical specialists.


Assuntos
Internet , Gravidez/estatística & dados numéricos , Gestantes/psicologia , Smartphone , Telemedicina/métodos , Adulto , Estudos Transversais , Tomada de Decisões , Feminino , Alemanha/epidemiologia , Humanos , Smartphone/estatística & dados numéricos , Inquéritos e Questionários , Telemedicina/estatística & dados numéricos
19.
Cytogenet Genome Res ; 146(3): 211-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406935

RESUMO

Despite similar genome sizes, a great variability in recombination rates is observed in mammals. We used antibodies against SYCP3, MLH1 and centromeres to compare crossover frequency, position along chromosome arms and the effect of crossover interference in spermatocytes of 4 species from the family Bovidae (Bos taurus, 2n = 60, tribe Bovini; Ovis aries, 2n = 54, Capra hircus, 2n = 60 and Ammotragus lervia, 2n = 58, tribe Caprini). Despite significant individual variability, our results also show significant differences in both recombination rates and the total length of autosomal synaptonemal complexes (SC) between cattle (47.53 MLH1 foci/cell, 244.59 µm) and members of the tribe Caprini (61.83 MLH1 foci, 296.19 µm) which can be explained by the length of time that has passed since their evolutionary divergence. Sheep displayed the highest number of MLH1 foci per cell and recombination density, although they have a lower diploid chromosome number caused by centric fusions corresponding to cattle chromosomes 1;3, 2;8 and 5;11. However, the proportion of MLH1 foci observed on the fused chromosomes in sheep (26.14%) was significantly lower than on the orthologous acrocentrics in cattle (27.6%) and goats (28.2%), and their distribution along the SC arms differed significantly. The reduced recombination rate in metacentrics is probably caused by interference acting across the centromere.


Assuntos
Bovinos/genética , Cabras/genética , Meiose/genética , Proteínas Nucleares/metabolismo , Recombinação Genética , Ovinos/genética , Espermatócitos/metabolismo , Animais , Hibridização in Situ Fluorescente , Masculino
20.
Int J Gynaecol Obstet ; 164(2): 778-785, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37571878

RESUMO

OBJECTIVE: To investigate how often antenatal corticosteroids (ACS) were administered within the optimal time frame in women at risk of preterm birth (PTB) in relation to several diagnoses and risk factors. METHOD: The study was designed as a retrospective cohort trial, in which the data of all births taking place in 2016 in the German federal state of Rhineland-Palatinate were evaluated. Frequency analyses, subgroup analyses, and logistic regression were performed. RESULTS: Birth occurred within the ideal time frame (≥24 h, ≤7 days) in only 15.2% of all pregnant women who were treated with ACS because of an increased risk of PTB (N = 1544). The ideal time frame after ACS administration was reached in less than 25% of all cases in each subgroup, with little difference between the different diagnoses and risk factors for PTB (range 11.3%-22.2%). Patients with multiple pregnancy had a significantly higher chance for delivery within the ideal time frame. There was an odds ratio greater than 1 for a birth event within the ideal time frame in patients with preterm prelabor rupture of membranes, pre-eclampsia, oligohydramnios, amniotic infection syndrome, and in patients with multiple diagnoses. In most diagnoses, the average time between ACS administration and birth was significantly shorter compared with patients without the diagnosis or risk factor. CONCLUSION: In women at risk of PTB, the individual risk profile should first be identified before ACS management begins. The likelihood of achieving the ideal time frame additionally depends on the diagnosis.


Assuntos
Complicações na Gravidez , Nascimento Prematuro , Feminino , Gravidez , Humanos , Recém-Nascido , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Estudos Retrospectivos , Corticosteroides/efeitos adversos , Gravidez Múltipla
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