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1.
Eur J Obstet Gynecol Reprod Biol ; 294: 76-78, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218162

RESUMO

While cesarean deliveries performed for health indications can save lives, unnecessary cesareans cause unjustifiable health risks for the mother, newborn, and for future pregnancies. Previous recommendations for cesarean delivery rates at a country level in the 10-15% range are currently unrealistic, and the proposed concept that striving to achieve specific rates is not important has resulted in a confusing message reaching healthcare professionals and the public. It is important to have a clear understanding of when cesarean delivery rates are deviating from internationally acceptable ranges, to trigger the implementation of healthcare policies needed to correct this problem. Based on currently existing scientific evidence, we recommend that cesarean delivery rates at a country level should be in the 15-20% range. This advice is based on the demonstration of decreased maternal and neonatal mortalities when national cesarean delivery rates rise to circa 15%, but values exceeding 20% are not associated with further benefits. It is also based on real-world experiences from northern European countries, where cesarean delivery rates in the 15-20% range are associated with some of the best maternal and perinatal quality indicators in the world. With the increase in cesarean delivery rates projected for the coming years, experience in provision of intrapartum care may come under threat in many hospitals, and recovering from this situation is likely to be a major challenge. Professional and scientific societies, together with healthcare authorities and governments need to prioritize actions to reverse the upward trend in cesarean delivery rates observed in many countries, and to strive to achieve values as close as possible to the recommended range.


Assuntos
Tocologia , Gravidez , Feminino , Recém-Nascido , Humanos , Cesárea , Mães , Mortalidade Infantil , Hospitais
2.
Mol Cancer Res ; 17(7): 1480-1492, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31043491

RESUMO

Dyskeratosis congenita is a telomere DNA damage syndrome characterized by defective telomere maintenance, bone marrow failure, and increased head and neck cancer risk. The Pot1b-/-;Terc+/- mouse exhibits some features of dyskeratosis congenita, but head and neck cancer was not reported in this model. To model the head and neck cancer phenotype, we created unique Pot1b- and p53-null-mutant models which allow genetic lineage tracing of two distinct stem cell populations. Loss of Pot1b expression depleted stem cells via ATR/Chk1/p53 signaling. Tumorigenesis was inhibited in Pot1b-/-;p53+/+ mice due to cellular senescence. Pot1b-/-;p53-/- tumors also exhibited senescence, but proliferated and metastasized with expansion of Lgr6+ stem cells indicative of senescence-associated secretory phenotype. Selective depletion of the small K15+ stem cell fraction resulted in reduction of Lgr6+ cells and inhibition of tumorigenesis via senescence. Gene expression studies revealed that K15+ cancer stem cells regulate Lgr6+ cancer stem cell expansion via chemokine signaling. Genetic ablation of the chemokine receptor Cxcr2 inhibited cancer stem cell expansion and tumorigenesis via senescence. The effects of chemokines were primarily mediated by PI3K signaling, which is a therapeutic target in head and neck cancer. IMPLICATIONS: Paracrine interactions of cancer stem cell populations impact therapeutic options and patient outcomes.


Assuntos
Proteínas de Ligação a DNA/genética , Neoplasias de Cabeça e Pescoço/genética , Receptores Acoplados a Proteínas G/genética , Proteína Supressora de Tumor p53/genética , Animais , Carcinogênese/genética , Linhagem da Célula/genética , Proliferação de Células/genética , Senescência Celular/genética , Dano ao DNA/genética , Disceratose Congênita/complicações , Disceratose Congênita/genética , Disceratose Congênita/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Comunicação Parácrina/genética , RNA/genética , Receptores de Interleucina-8B/genética , Telomerase/genética , Telômero/genética , Homeostase do Telômero/genética
3.
Pract Midwife ; 18(2): 22-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26333248

RESUMO

Historically antenatal education has been seen as an important part of antenatal care and a mechanism to provide women with close to realistic interpretations of childbirth and motherhood. Through the years, the main themes and emphases of parenting education have changed, sometimes to reflect the new socio-economic structure and sometimes forced by the women themselves seeking specific information and knowledge. Yet again, this time the invasion of online information and social media is about to change the perception and the philosophy of antenatal education from an informative opportunity to a powerful and effective intervention.


Assuntos
Instrução por Computador/métodos , Mães/educação , Cuidado Pré-Natal/organização & administração , Educação Pré-Natal/organização & administração , Feminino , Humanos , Internet , Comportamento Materno , Educação de Pacientes como Assunto , Gravidez
4.
Beilstein J Org Chem ; 4: 12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18941484

RESUMO

BACKGROUND: Sphingolipids belong to the most important constituents of the membranes of eukaryotic cells. As intermediates in sphingolipid metabolism, sphingosine and its N-octadecanoyl-derivative, ceramide, exhibit a variety of biological functions. These compounds play a crucial role in many essential biological processes such as cell growth, cell differentiation, cell recognition and apoptosis. More specifically, sphingolipids are crucial e.g. for the function of the skin because they contribute to the formation of the water permeability barrier consisting of a highly organized multilaminar lipid matrix of free fatty acids, cholesterol and ceramides containing additional hydroxyl groups in the sphingosin part and longer fatty acid amide functions. RESULTS: In a short synthetic route (2S,3S)-4-fluorosphingosine and 4-fluoroceramide, the fluorinated analogues of the natural products, D-erythro-sphingosine and ceramide, have been prepared. The key step of the synthetic sequence is an asymmetric aldol reaction of (Z)-2-fluorohexadec-2-enal, prepared in three steps from tetradecanal, with an enantiopure N-protected iminoglycinate. Deprotection of the imino function and reduction of the ester group led to the 4-fluorosphingosine, which on acetylation with stearoyl chloride gave 4-fluoroceramide. After careful HPLC purification of the latter compound its phase behavior was investigated by Langmuir film balance technique and compared to that of natural ceramide. While the isotherms are quite similar in shape, they differ significantly in the starting point of increasing film pressure (56 or 67 A(2)/molecule) and in the film collapse pressure (38 or 56 mN/m) for ceramide and 4-fluoroceramide, respectively. Moreover, the hysteresis curves are very different. While consecutive isothermic compression - expansion cycles are reversible for the 4-fluoro derivative, substantial substance loss into the subphase or irreversible formation of multi-layers was observed for natural ceramide. CONCLUSIONS: Asymmetric aldol reaction proved to be successful for the preparation of enantiopure 4-fluoroceramide. Surface/pressure isotherms and hysteresis curves of ceramide and its 4-fluoro derivative showed that the presence of fluorine leads to stronger intermolecular interactions between the hydrophobic chains of neighboring molecules, and therefore to increasing stability of the monolayer of 4-fluoroceramide at the air water interface.

5.
Acta Bioeng Biomech ; 10(1): 3-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18634348

RESUMO

On the basis of a representative anthropological investigation of 5290 individuals (2435 males and 2855 females) of the Bulgarian population at the age of 30-40 years (Yordanov et al. [1]) we proposed a 3D biomechanical model of human body of the average Bulgarian male and female and compared two different possible approaches to calculate analytically and to evaluate numerically the corresponding geometric and inertial characteristics of all the segments of the body. In the framework of the first approach, we calculated the positions of the centres of mass of the segments of human body as well as their inertial characteristics merely by using the initial original anthropometrical data, while in the second approach we adjusted the data by using the method based on regression equations. Wherever possible, we presented a comparison of our data with those available in the literature on other Caucasians and determined in which cases the use of which approach is more reliable.


Assuntos
Aceleração , Constituição Corporal/fisiologia , Movimento/fisiologia , Adulto , Fenômenos Biomecânicos/métodos , Bulgária/epidemiologia , Simulação por Computador , Feminino , Gravitação , Corpo Humano , Humanos , Masculino , Modelos Biológicos , Grupos Populacionais , Análise de Regressão
6.
J Biomech ; 40(16): 3700-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17662989

RESUMO

Based on a large-scale anthropometric measurements of 5290 individuals (2435 males and 2855 females) of the Bulgarian population aged between 30 and 40 years, we present 16-segmental 3D geometrical model of the human body of the average Bulgarian male and female and calculate mass, volume, location of the mass center and moments of inertia for all the segments for both genders. This study extends current anthropometrical data pool of Caucasian. Wherever possible, the comparison between our model results and data reported in literature for other Caucasian shows an overall good agreement, thus supporting the validity of the described method.


Assuntos
Antropometria/métodos , Tamanho Corporal/fisiologia , Modelos Anatômicos , Modelos Biológicos , Projetos Ser Humano Visível , Adulto , Bulgária , Simulação por Computador , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Distribuição por Sexo , Fatores Sexuais
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