907 resultados para Premature luteolysis


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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In cattle, proestrus begins with the initiation of luteolysis and ends with initiation of estrus and the GnRH/LH surge. This period is marked by a dramatic decrease in circulating progesterone (P4) that reaches a nadir by about 36-48 h in cows undergoing natural or prostaglandin F2 alpha (PGF)-induced luteolysis. Inadequate luteolysis is a cause of reduced fertility particularly in timed AI programs with small elevations in circulating P4 reducing fertility. Increasing circulating estradiol (E2) during proestrus is dependent on presence, size, and function of the dominant follicle and this varies during natural proestrus, due to whether animals have two or three follicular waves, and during PGF-induced proestrus, according to stage of the follicular wave at time of PGF treatment. Inadequate circulating E2 can limit fertility and increase pregnancy loss in some specific circumstances such as in cows with low BCS and in cows during heat stress. Thus, studies to optimize the length of proestrus and the concentrations of E2 and P4 during proestrus could produce substantial improvements in fertility and reductions in pregnancy loss.

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Modern protocols to synchronize ovulations for timed artificial insemination and timed embryo transfer that include manipulations in the proestrus period (i.e., between luteolysis and estrus) affect fertility in cattle. Specifically, stimulating pre-ovulatory follicle growth and exposure to estrogens after CL regression increase the proportion of cows pregnant and decrease late embryo mortality. Such effects may be due to both preovulatory actions of estrogens and post-ovulatory actions of progesterone, as concentrations of the later hormone may be changed in response to manipulations conducted during proestrus. In the first portion of this paper we describe strategies used recently to manipulate the proestrus period in protocols for synchronization of ovulation, and to present evidence of their effects on fertility. Manipulations of timing and prominence of sex steroids during the proestrus and early diestrus that affect fertility may act on targets such as the endometrium. This tissue expresses receptors for both estrogens and progesterone and these hormones change endometrial function to support conceptus growth and pregnancy maintenance. However, specific cellular and molecular mechanisms through which fertility is affected via manipulations of the proestrus are poorly understood. In the second portion of this paper we describe a well-defined animal model to study changes in endometrial function induced by manipulations conducted during the proestrus. Such manipulations induced endometrial changes on sex steroid receptors expression, cell proliferation, oxidative metabolism and eicosanoid synthesis in the uterus, but not on glucose transport to uterine lumen. In summary, evidence is accumulating to support a positive role of increasing duration and estrogen availability during the proestrus on fertility to synchronization protocols. Such positive effects may be through changes in endometrial function to stimulate conceptus growth and survival.

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The modernization of image equipaments associate to the veterinary professionals qualification allowed an advance in diagnosis veterinary medicine, and, consequently, in premature pregnancy diagnosis in bitches. Currently, owners and creators search for information related to pregnancy detection, fetal development and viability and litter size determination. Through diagnosis methods as radiology and ultrasonography, associated to clinics aspects, the diagnosis of early pregnancy become more acurated and precise, allowing more quality in the accompaniment of prenatal of these bitches. Ultrasonographic exams help the accompaniment of these pregnancies through of visuals recourses, which can supply information related to pregnancy detection, embrionary and fetal development, fetal viability e litter size determination through fetals mensurations. The radiographic study has as principal indication the fetal counting, and has been the most acurated for this analyses. It may be done after the da s after the luteini ing hormone surge, when occurs the fetal mineralization. Due to its importance in the present time and in small animals clinic, the objective of this study is to discuss the main radiographics and ultrassonographics aspects of the diagnosis of pregnancy in bitches

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The concern with infant mortality has been a priority in public policies, especially for Brazil to achieve the Millennium Development Goal number four: reducing child mortality by 75% by the year 2015. It is known that prematurity has an intimate relationship with mortality of children under one year and therefore it is necessary an effective intervention in risk factors linked to premature births. To evaluate the profile of mothers and newborn babies living in Botucatu-SP, in the period 2001 to 2009, focusing on prematurity. A quantitative study, retrospective, descriptive, epidemiological, from the Information System Newborn Alive. The prevalence of preterm births was 15.1%, and low birth weight 14.7%. Among infants, the Apgar score below 7 at 1 and at 5 minutes was 13.1% and 2.4% respectively. Considering the total of pregnant women studied, 20.3% were adolescents and 10.3% were aged 35 years or more and most (63.2%) had eight or more years of school approval. The profile of mothers of premature infants shows that 23.6% were teenagers, 14.1% had at least 35 years and 60.4% had at least primary education. With regard to premature deliveries, caesarean sections and 58.4% were between the total newborns, this type of delivery was achieved in 46.6% of cases. Prematurity was associated with an Apgar score below seven in the first and fifth minutes of life, presence of malformation and multiple pregnancy. Among maternal variables, prematurity was associated with extremes of maternal age, maternal education, history of stillbirth, primiparas, white and presence of the mother's partner. With regard to delivery was associated with cesarean section and outside the hospital. This study assessed maternal characteristics associated with prematurity and point out how relevant the pregnancies at the extremes of age and those that occur in women with low education level, indicating the interference... (Complete abstract click electronic access below)

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Some characteristics and behaviors, that are of young, as a tendency to rebel and take risks, deviating from the rules of society, makes it vulnerable to many detrimental aspects, such as may indiscriminate use of alcohol and drugs, practicing unsafe sex and having multiple partners, which cause, among another complications, sexually transmitted diseases (STD). The Chlamydia trachomatis causes chlamydial infection, is one of the most recurrent STD of the world. Several risk factors are already defined for Chlamydial infection, among them, age under 25 years old and sexual behavior of the risk. The objective was to determine the prevalence of Chlamydia infection cervicitis in adolescent females of the Botucatu, São Paulo, and risk factors associated with this infection. It is cross-sectional study, of the populational basis, performed together the nineteen basic health units of the Botucatu, São Paulo. The data were obtained through clinical interviews and gynecological examination on samples collected for laboratory analysis. The research of C. trachomatis was performed by polymerase chain reaction (PCR). This report presents preliminary data, which represent 19% of the sample checked. Were interviewed 37 adolescents with a mean age of 17 years (between 15th and 19th years old), average of years studied of the 8,19, 40% of the families lived on less than a minimum wage by person and 24,3% dosen’t has ownership of the house where they live. Mean age of first sexual intercourse of 14 years (between 12th and 16th years old), 24,3% regularly used condoms, 5,4% had a premature birth and 8,1% reported abortion. 75,7% had any complaints in the gynecological exam, pain in lower abdomen, the most prevalent. The prevalence of vulvovaginitis or vaginal flora altered was 54,1%. The prevalence of infection by C. trachomatis was 58%. Presence content was associated infection chlamydial and age... (Complete abstract click electronic access below)

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Introduction: Preterm Labor (PTL) and Preterm Premature Rupture of Membranes (PPROM) cause severe complications for both mother and fetus. Among the risk factors associated with preterm labor and PPROM, genetic predisposition has been gaining importance. However, the association between polymorphic genes and the pathogenesis of PTL and PPROM remains elusive. A better understanding of the genetic mechanisms underlying these adverse pregnancy outcomes may enable the identification of high risk patients and allow new approaches to minimize the deleterious effects of prematurity. Aim: To determine the association between maternal IL-6 polymorphism gene and the occurrence of PTL and PPROM. Patients and Methods: The study included 109 patients with prior history of PL and/or PPROM that delivered prematurely at the Obstetrical Unit Care of Botucatu Medical School, UNESP between 2003 and 2012. The control group consisted of 68 patients that delivered at term, matched to the case group by age, ethnicity, and sex of the newborn. Oral swabs (Cath-AllTM – Epicentre Biotechnologies) were collected for analysis of genetic polymorphisms by PCR. Statistical tests were performed to compare genotype, clinical and socio-demographic data from the groups. A p-value of <0.05 was considered significant. Results: The sociodemographic characteristics in both groups were homogeneously distributed. The frequency of the polymorphic allele C, associated with less production of IL-6, and therefore thought to be protective against PTL and PPROM, was 32,5% in the study group and 30,9% in the control group, without statistically significant differences. Conclusion: Considering the sample size included in this study, the frequency of the mutated allele is similar in pregnant women who delivered at term and gestational complications as PTL and PPROM

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Current cattlemen must seek methods to maximum reproductive efficiency of their beef herds, making the business competitive and enhancing greater profitability. For the cow-calf producers, efficiency translates into more cows producing one calf every year. Fixed-time artificial insemination (TAI) is one of several technologies that producers utilize to reach this goal. Postpartum anestrus is one of the biggest obstacles to overcome in order to obtain suitable results at the end of the breeding season. The TAI protocols are efficient in re-establishing cyclicity in noncycling cows during the postpartum period, streamlining the use of labor on farms, allowing the use of artificial insemination (AI) on a large scale, and introducing superior genetics to the herd. The protocols that are most commonly used in Brazil are based on progesterone (P4) releasing devices that prevent premature estrus and ovulation; and estradiol (E2) to synchronize the initiation of a new follicular wave. In such protocols, administration of equine chorionic gonadotropin (eCG) helps the development of the follicle, increases ovulation rate, improves the endocrine and uterine environment during proestrus and diestrus, and improves fertility. The use of eCG in TAI protocols for suckled cows, non-lactating cows and heifers increases the pregnancy rate allowing more calves at the end of the breeding season and higher profitability to the cattlemen

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In the last years, the embryo in vitro production for every domestic species and mainly for bovine has attained a notorius status. This reproductive biotechnical procedure associate with ultrasound-guided ovum pick up (OPU) has been more and more incorporated and spread in our cattle herds, ranking up Brazil already at the top of the list in number of in vitro embryo produced. Some significant advantages provided, such as the possibility of using the premature or pregnant animals oocytes, without necessarily requiring the use of hormonal treatment, to make it possible to generate pregnancy at a shorter period of time, the rationalization in the use of semen and optimization in the use of sexed semen were determinant factors for OPU/IVP to reach this outstanding position. Nevertheless, right now the possibility of IVP embryo cryopreservation, just now is the biggest impediment for maximizing the use of this biotechnology, due to both lack of efficient methods and low laboratory produced embryo cryotolerance. Nowadays, the most used methods of IVP embryo cryopreservation are: slow freezing and vitrification. Traditionally, slow freezing is still the most used methods for in vivo and in vitro produced embryo cryopreservation. However, more recently vitrification - although still not commercially used in large scale - has been presenting satisfactory results in IVP embryo cryopreservation, according to searches

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Pneumonia is a respiratory disease that most affects the cattle, especially calves, which according to their anatomical and physiological characteristics are more susceptible to respiratory diseases compared to other large mammals. Therefore, prevention of pneumonia is a key factor to minimize the possible economic losses generated by the early involvement of a calf by these diseases, which can cause a decrease in animal development. Despite the multifactorial etiology and classification on the types of pneumonia is still subject of discussion, most pneumonias are in three categories: bronchopneumonia, interstitial pneumonia and metastatic pneumonia, the first being the most important among them. Clinical signs vary with the cause, but are classified as medical conditions ranging since subclinical to clinically irreversible. Treatment depends on the clinical experience and can associate drugs for alleviating the symptoms with anti-inflammatories and antibiotics. Thus, premature diagnosis is directly linked to prognosis, treatment costs and spread of the disease

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The machining of super alloys resistant to high temperatures such as nickel alloys, inconel 718 specifically, is a very difficult job to obtain improvements in the process, due to the difficulty of machining at high cutting speeds, the use of these alloys in industries showed great developments in recent years, its application in aeronautical industry spread being used in vane turbo, compressor parts, props and set elements. The automotive, chemical, medical and others also took advantage of the great features of inconel 718 and has used the material. The high temperature resistant alloys have high machining difficulty, a fact that is associated with high cutting forces generated during machining which result in high temperatures. High levels of temperatures can cause deterioration of the cutting edge, with subsequent deformation or breakage, wear most common obtained in machining such materials are flank wear the formation of built-up edge for cutting and notch wear. The experimental part of the work consists in machining of nickel-based alloy Inconel 718 heat treated for hardness, using a tool based ceramic silicon nitride Sandvik (Si3N4) in order to compare the best results obtained in the master's thesis of SANTOS (2010) who used a tool ceramics also the basis of silicon nitride which was developed in the doctoral thesis of SOUZA (2005). Assays were performed on a CNC lathe and was noted for each cutting edge results obtained. Tests were made starting from an initial condition of the tool with cutting speed of 200 m/min, feed 0.5 mm and 0.5 mm depth of cut was reduced cutting speed for the subsequent tests with the same conditions of feed and depth of cut. The tool presented wear instant under two 200 m/min and 100 m/min, premature rupture of 50 m/min and finally cut provided with difficulty... (Complete abstract click electronic access below)

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Pós-graduação em Medicina Veterinária - FCAV

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Pós-graduação em Saúde Coletiva - FMB

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)