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PubMed2005

Men's role in emergency obstetric care in Osun State of Nigeria.

This study was conducted among the Yoruba of South-West Nigeria to examine the role of men in emergency obstetric care, as men determine whether and when their spouses visit health clinics in most cultures. Simple random sampling was used to select 900 households from three communities in Osun State, south-west Nigeria. Separate interviewers interviewed the man and his wife in each of the households. In polygamous families, two wives of reproductive age were also interviewed. The quantitative survey was complemented with a number of focus group discussions, in-depth interviews and key informant interviews. There was high level of awareness of emergency obstetric conditions by men, particularly in relation to pregnancy signs and labour pains (53.2%). Respondents reported that men play useful roles during their partner's obstetric conditions (89.2%). Women take decisions on health-seeking behaviour during emergency obstetric conditions in the absence of the male partner. Education is found to be the major determinant of this change in male knowledge and behaviour. There is a need to further promote universal basic education in the country especially in areas where the observable change in this study has not been noted. There is also a need to extend the study to other zones in Nigeria in order to have a national picture.

Adolescent↗

PubMed1989

[Diagnosis and management of habitual reproductive wastage].

Our recent 10 years statistical survey at Keio University indicates that 1,877 spontaneous abortions are recorded in total 9,200 pregnancies, thus showing approximately 16.95 per cent wastages in known conceptions. In the present study, possible statistics on reproductive wastages are collected and summarized, then comprehensive examinations on the causes of habitual abortion were performed on our registered patients. Appropriate therapy was selected and its clinical result was also analysed. Eight hundred and thirty eight couples were registered as repeatedly or habitually aborted patients. Among these, 124 women repeatedly aborted due to congenital uterine anomaly, mainly bicornuate or arcuate uterus. A new method to evaluate uterine deformities related to abortion rate was introduced, while basic research was also performed to elucidate exact mechanism of abortion in these uteri by analysing distribution of arteries in both abnormal and normal control tissues. The results indicate that numbers of uterine arteries were significantly reduced in congenital abnormal uterus as compared to control. An ideal metroplasty was introduced from the research results. Twenty four children were born after 27 metroplasties, while no full term baby was delivered in 96 pregnancies before surgical operation. Fifty four women were suffering from habitual abortions due to chromosomal abnormalities among 639 couples examined. Karyotype analysis indicates that most frequent abnormalities were translocations, inversions as well as other variants. Extremely high incidence of spontaneous abortions were observed in each type of abnormality, suggesting ample time should be payed for genetic consultation. Luteal insufficiency and other diseases including anti-phospholipid syndrome were detected, however other 351 cases showed no significant abnormality except HLA compatible among the couples.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Habitual↗

PubMed2005

Regulation of primordial follicle assembly and development.

The assembly of the primordial follicles early in ovarian development and the subsequent development and transition of the primordial follicle to the primary follicle are critical processes in ovarian biology. These processes directly affect the number of oocytes available to a female throughout her reproductive life. Once the pool of primordial follicles is depleted a series of physiological changes known as menopause occur. The inappropriate coordination of these processes contributes to ovarian pathologies such as premature ovarian failure (POF) and infertility. Primordial follicle assembly and development are coordinated by locally produced paracrine and autocrine growth factors. Endocrine factors such as progesterone have also been identified that influence follicular assembly. Locally produced factors that promote the primordial to primary follicle transition include growth factors such as kit ligand (KL), leukaemia inhibitory factor (LIF), bone morphogenic proteins (BMP's), keratinocyte growth factor (KGF) and basic fibroblast growth factor (bFGF). Factors mediating both precursor theca-granulosa cell interactions and granulosa-oocyte interactions have been identified. A factor produced by preantral and antral follicles, Müllerian inhibitory substance, can act to inhibit the primordial to primary follicle transition. Observations suggest that a complex network of cell-cell interactions is required to control the primordial to primary follicle transition. Elucidation of the molecular and cellular control of primordial follicle assembly and the primordial to primary follicle transition provides therapeutic targets to regulate ovarian function and treat ovarian disease.

Animals↗

PubMed2001

[Assisted reproductive medicine in the next age].

Medicine is going from success to success, but with the ever-increasing expectations of the society, the more it achieves, the less it satisfies. This is also true for reproductive medicine. Indeed, advances in basic research and the practical applications of the research that have been performed since the first successful in vitro fertilisation (IVF) in 1978, have given rise to hitherto unimaginable strategies for achieving human reproduction. Couples, that were considered sterile only a few years ago, can now acquire assistance conceiving. Twenty two years after Louise Brown was born, the reproductive medicine methods have spread all over the world and thousands of children have been born as a result of these techniques. ICSI applied to epididymal or testicular sperm in cases of azoospermia permits infertile men to become fathers. Even if the results of reproductive medicine have improved in terms of numbers of pregnancies, it is still striking that it is necessary to use stimulation which sometimes leads to hyperstimulation and multiple pregnancies, that embryo development in vitro is still limited, that implantation only occurs for 15-20% of embryos and this ratio have not changed in the last 20 years. The pregnancy rates currently obtained with IVF are at the most similar to those occurring in vivo. We still need to improve techniques to gain pregnancy rates approaching 50% per embryo. In order to fullfil this task, we need to introduce less aggressive and much simpler ovarian stimulation, routine culture of embryos to the blastocyst stage, pre-implantation genetic diagnosis, cryopreservation and in vitro maturation of oocytes and finally to improve the implantation rates by our ability to understand and control the dialog between blastocyst and receptive endometrium.

Cryopreservation↗

PubMed1983

[Blood sugar in dairy cows].

Glycemia was found in 1270 cows and high-pregnant heifers fed summer feed rations and in 1981 cows fed winter feed rations, with the known levels of energy-yielding nutrients in feed rations for cows in the first (I) and in the second (II) lactation phases and cows and heifers in the eighth to ninth and a half month of pregnancy (III). The levels of glycemia were significantly lower after the summer feed rations than after the winter feed rations, both in the whole population and in all groups. The basic type of feed rations has a stronger influence on the level of glycemia than the phase of the reproduction cycle. In all groups, hypoglycemic deviations prevail over hyperglycemic ones. Hypoglycemia is most expressive in group I, least expressive in group III. The coefficient of glycemia variability is high (26.5 to 34.6); it is higher after the winter feed rations. Covering of the nutrient need is significantly higher in the summer period than in the winter period, the narrow calorie-protein ratio prevails over the increased ratio and is most obvious in groups II and III. Gaussian character of the glycemia distribution curves suggests a large number of independently acting factors, none of them prevailing over the others; the effects of these factors are mostly additive. This phenomenon limits strongly the employment of glycemic values as indicators of the energy balance in the organism. Glycemia is to be judged within the framework of the metabolic profile and nutritive indicators. Further study of glycemia should be performed by means of multivariate statistical methods.

Animal Feed↗

PubMed2005

Transcriptional regulation of early oogenesis: in search of masters.

Transcription factors in the germline play important roles in ovary formation and folliculogenesis, and control both oocyte development and somatic cell function. Factor in the germline (Figla) and newborn ovary homeobox gene (Nobox) represent a growing number of oocyte-specific transcription factors that regulate genes unique to oocytes. Studies on oocyte-specific transcription factors are important in understanding the genetic pathways essential for oogenesis, pluripotency, and embryonic development. Likely, these genes regulate reproductive life span and represent candidate genes for reproductive disorders, such as premature ovarian failure, and infertility. Therefore, oocyte-specific transcription factors, and oocyte-specific genes regulated by such factors, are attractive tissue-specific pharmacological targets to regulate human fertility.

Animals↗

PubMed1990

[An attempt of introduction to prosthodontics of a non-contact device for measuring small configurations. Determining configurational changes during the individual steps of denture fabrication].

Denture fabrication involves a number of complex operations that have an effect on reproduction accuracy during each step of the process. Traditionally, metal patterns act as the standard for the mechanical properties of the main materials used in denture making. This means that doubts still remain in cases where the mucous membrane, with its complex configurations, is the object of investigation. The non-contact measuring instrument using laser light (known hereafter as "measuring instrument") enabled measuring small configurations. The measuring instrument enabled measurement of physical configurations that up to now were considered impossible to measure. The fabrication process up to creation of a denture base with the mucous membrane as the basic pattern was divided into four steps for measurement: mucous membrane, impression material, plaster and resin. The measuring device simultaneously carried out qualitative and quantitative analysis in three dimensions for all steps. Processing of test materials was unnecessary so that measurements could be accomplished in a very short time. Measurements revealed a variety of features, including those that are not affected by the physical properties of the materials for measurement. It was also possible to systematically investigate the various changes that take place during denture fabrication with the mucous membrane acting as the basic pattern. The following results were obtained: 1. The experiment confirmed possible application in dentistry of a non-contact device that uses laser light to measure extremely small configurations. 2. Results hint at the possibility of quantitative measurement of objects that cannot be directly measured with conventional methods. 3. During fabrication of dentures, it is very easy for changes in the total configuration to occur when taking impressions. Minute changes in the configuration occur on the surface when taking the plaster cast. During the final stage of the resin base, the tiny configurations became flat and resembled the configuration of the impression more than the original configuration of the mucous membrane.

Denture Bases↗

PubMed1982

The fitness of categories and vice versa.

Two basic propositions are developed as useful in an evolutionary analysis of the origins of complex biobehavioral categories: 1. Such categories derive from the gradual accumulation of a very large number of categoric alternatives, each of which is very small, and 2. Fitness considerations provide valuable insight into the ultimate decision process whereby these micro-categories, and thus eventually, all more complex categories, are achieved.

Adaptation, Biological↗

PubMed1970

Electrophysiological aspects of human sphincter function.

In order to investigate the electrophysiology of the human internal anal sphincter and two current concepts of sphincter function, simultaneous manometric and electrical recordings were made from circular smooth muscle of the internal anal sphincter in the resting state and during reflexly induced sphincter relaxation. Three groups were studied: seven normal subjects, 25 patients with functional bowel disease, and seven patients with external sphincter paralysis due to spinal cord lesions. In the resting state slow waves of alternating potential (basic electrical rhythm or BER) were recorded in all subjects. Two types of waves were present, a constant sinusoidal pattern or a spindleshaped pattern. Either pattern was consistent for a given individual. Frequency of BER in the internal sphincter was higher than that recorded in any other gastrointestinal muscle. Our findings indicate that the BER recorded from the internal anal sphincter originates in this muscle. This activity may represent a specialized feature of sphincteric muscle since BER cannot be recorded from isolated nonsphincteric circular muscle. Reproduction of the two patterns of BER by an electronic model suggests that BER, as recorded by this technique, results from a summation of a number of electrically active cells in contact with the recording electrodes. Inhibition of BER occurred when sphincter relaxation was reflexly induced by rectal distension. Both inhibition of BER and degree of sphincter relaxation were proportional to the strength of rectal stimulation, suggesting that strength of stimulus determines the number of active cells which are inhibited. The associations of high frequency of BER with high resting pressure, and of inhibition of BER with sphincter relaxation suggests that maintenance of sphincter tone is an active process that is governed by BER.

Adolescent↗

PubMed1985

Genetics of factors affecting the life history of Drosophila melanogaster. I. Female productivity.

Starting from four basic strains of Drosophila melanogaster, two laboratory strains (cn bw, Tokyo) and two isofemale lines (B-102, B-103) originated from a wild population in Texas, we constructed by repeated backcrosses through females for 20 or more generations a total of 16 strains of all possible combinations between the chromosome sets and cytoplasmic classes. Females from these 16 synthesized strains were then examined for their reproductive performance during their entire life span.---The chromosome set from the cn bw strain was found to associate with the highest female productivity when the age of females was very young, but these females ceased their reproduction and died relatively earlier, resulting in a smaller number of total progeny. The B-102 and B-103 chromosome sets, on the other hand, were associated with the lowest productivity when the females were young, but they lived and continued reproduction longer, resulting in a larger number of total progeny. The Tokyo chromosome set was associated with female productivity intermediate between the other two groups.---Cytoplasmic factors were found to affect the productivity of young females, with the cytoplasm from the cn bw strain associated with the highest productivity. Longevity was not cytoplasmically affected.---There was a clear interaction in female productivity between the Tokyo chromosome set and the cytoplasm from the Texas isofemale lines; the lifetime female productivity, as well as longevity, associated with the Tokyo chromosome set was found to increase considerably when it was substituted into the cytoplasm of the Texas isofemale lines. This chromosome-cytoplasm interaction appeared to be independent of the two systems of hybrid dysgenesis.

Chromosomes↗

PubMed1994

[External control of drug sensitivity determination in mycobacteriologic laboratories in the Czech Republic].

In 1992 and 1993 an external control of sensitivity assessment of coded strains of M. tuberculosis to five basic antituberculotics was made: isoniazide, streptomycin, pyrazinamide, ethambutol and rifampicin. In 1992 from 11 participating laboratories an erroneous result was recorded in 9 (3 laboratories made two mistakes, 6 laboratories one mistake), two laboratories did not provide complete results. Unsatisfactory results were obtained during external controls in 1993. Of 15 participating laboratories four laboratories made one mistake, two laboratories two mistakes, four laboratories three mistakes. Five laboratories (i.e. one third) made more than three mistakes. Analysis of the results revealed a low reproductibility of results of drug sensitivity tests. To eliminate these shortcomings it will be necessary to make systematic external controls with subsequent solution of the shortcomings, restriction of the number of laboratories making these examinations to those who will systematically produce correct results. And it will be also necessary to test the sensitivity tests to antituberculotics in resistant strains in the National reference laboratory for mycobacteria.

Antitubercular Agents↗

PubMed1989

The role of Cayo Santiago in primate field studies.

Cayo Santiago has provided the opportunity to study primate biology in a free-ranging neutral environment free of provocative human influences. Rarely, if ever, does such a situation occur in natural rhesus habitats in Asia. This Cayo Santiago advantage has permitted fine-scale analyses of the details of behavior, ecology, reproduction, genetics, demography, and pathobiology with a greater degree of precision than is possible in the field. At the same time, research on Cayo Santiago has provided valuable baselines for comparative work with natural populations in Asia. Field and laboratory work with the Cayo Santiago colony has produced an impressive number of pioneering studies, from the first investigations of Carpenter in the late 1930's, to the recent demonstrations of Kessler and Rawlins on the demographic role of tetanus in rhesus population ecology and the effectiveness of an inoculation program in eliminating infectious disease. Few, if any, primate colonies have had such a productive interface of naturalistic studies of behavior and ecology with basic biomedical research.

Academies and Institutes↗

PubMedDate not supplied

Women's reproductive health--challenges for the 1990s.

Health policy makers, program planners and donor agencies have paid little attention to issues surrounding women's reproductive health. This paper will look at reproductive health issues surrounding pregnancy and childbirth, the accessibility and safety of contraception, and reproductive tract infections. The gross social injustice caused by high maternal mortality can no longer be ignored. Nor can we ignore the much larger numbers of women who suffer life-long health impairment resulting directly from the health hazards associated with pregnancy and childbirth. The challenge is to reduce maternal mortality by at least 50% by the year 2000. If these challenges are not faced, the 1990s may very well be remembered as the decade that saw the largest numbers of women dying in childbirth and pregnancy. The 1990s will see the addition of some 300 million couples to the reproductive age group. These couples will need access to good sexual health care, including safe and effective contraception, and prevention of reproductive tract infections and sexually transmitted disease. The biomedical consequences of reproductive tract infections are, among others, fetal wastage, low birth weight, carcinoma of the cervix, infertility and ectopic pregnancy. In addition to these consequences, there are the psychological, social and economic costs of these diseases. Some suggestions for meeting these challenges are put forward. These include building on existing programs and expanding available resources to help women to attain health, dignity, and their basic human rights.

Female↗

PubMed2000

Molecular signaling in pathogenicity and host recognition in smut fungi taking Karnal bunt as a model system.

Karnal bunt of wheat, incited by a phytopathogen Tilletia indica (Syn. Neovossia indica) is a floret infecting disease. In the floral tissues fungus proliferates and produces massive amount of black spores. In smut fungi, belonging to order Ustilaginales, communication between cells is necessary to regulate growth, differentiation and monokaryotic to dikaryotic transition during pathogenic and sexual development. Neighbouring cells are able to communicate with each other by direct cell to cell contact through plasma membrane bound signaling molecules or through formation of gap junctions and alternatively through secretion of chemical signals if cells are some distance away. Current research efforts toward understanding of pathogenic and sexual development in phytopathogenic fungi, offer a number of opportunities. These include the analysis of molecular signal(s) for direct contribution of sexual interactions to ability of smut and bunt pathogens to cause disease. These efforts will provide not only to explore the mechanisms of pathogenesis, but also to enhance knowledge of basic cellular biology of an economically important group of fungi.

Cell Communication↗

PubMed1999

Transmission of classical swine fever virus within herds during the 1997-1998 epidemic in The Netherlands.

In this paper, we describe the transmission of Classical Swine Fever virus (CSF virus) within herds during the 1997-1998 epidemic in The Netherlands. In seven herds where the infection started among individually housed breeding stock, all breeding pigs had been tested for antibodies to CSF virus shortly before depopulation. Based upon these data, the transmission of CSF virus between pigs was described as exponential growth in time with a parameter r, that was estimated at 0.108 (95% confidence interval (95% CI) 0.060-0.156). The accompanying per-generation transmission (expressed as the basic reproduction ratio, R0) was estimated at 2.9. Based upon this characterisation, a calculation method was derived with which serological findings at depopulation can be used to calculate the period in which the virus was with a certain probability introduced into that breeding stock. This model was used to estimate the period when the virus had been introduced into 34 herds where the infection started in the breeding section. Of these herds, only a single contact with a herd previously infected had been traced. However, in contrast with the seven previously mentioned herds, only a sample of the breeding pigs had been tested before depopulation (as was the common procedure during the epidemic). The observed number of days between the single contact with an infected herd and the day of sampling of these 34 herds fitted well in the model. Thus, we concluded that the model and transmission parameter was in agreement with the transmission between breeding pigs in these herds. Because of the limited sample size and because it was usually unknown in which specific pen the infection started, we were unable to estimate transmission parameters for weaned piglets and finishing pigs from the data collected during the epidemic. However, from the results of controlled experiments in which R0 was estimated as 81 between weaned piglets and 14 between heavy finishing pigs (Laevens et al., 1998a. Vet. Quart. 20, 41-45; Laevens et al., 1999. Ph.D. Thesis), we constructed a simple model to describe the transmission of CSF virus in compartments (rooms) housing finishing pigs and weaned piglets. From the number of pens per compartment, the number of pigs per pen, the numbers of pigs tested for antibodies to CSF virus and the distribution of the seropositive pigs in the compartment, this model gives again a period in which the virus most probably entered the herd. Using the findings in 41 herds where the infection started in the section of the finishers or weaned piglets of the age of 8 weeks or older, and of which only a single contact with a herd previously infected was known, there was no reason to reject the model. Thus, we concluded that the transmission between weaned piglets and finishing pigs during the epidemic was not significantly different from the transmission observed in the experiments.

Animals↗

PubMed2004

Sex ratio and size structure of Micropogonias furnieri (Desmarest, 1823) (Perciformes, Sciaenidae) in Sepetiba Bay, Rio de Janeiro, Brazil.

Sex ratio and size structure constitute basic information in assessing reproductive potential and estimating stock size in fish populations. One hundred fifty-one individuals of Micropogonias furnieri caught by experimental otter trawls, in three zones (inner, central, and outer) of Sepetiba Bay between October 1998 and September 1999 were examined. Males outnumbered females (1.3:1.0) in all zones but no significant differences were detected. Only in the outer zone (5.0:1.0) were male/female rates significantly different according to the chi-square test. No temporal differences were observed in sex ratio. Fish size ranged from 81 to 244 mm total length (TL) with significant differences in 155 to 185 mm TL size classes, where males predominated, and a slightly higher number of females were observed for the smaller size class (TL = 95-150 mm). Size distribution varied according to the zone, with juveniles predominating in the inner and adults in the outer zone. Spatial difference in size structure observed in this study indicates that the inner bay is a rearing ground during the first life-cycle period, and movement toward the sea occurs as fish increase in size.

Animals↗

PubMed2006

Sperm cryopreservation in oncological patients: a 14-year follow-up study.

OBJECTIVE: Oncologic treatments can destroy spermatogenic dividing cells and cause azoospermia which could be irreversible. Sperm banking is the best option to preserve male fertility after these treatments. It is easy, inexpensive, and safe. To date, few clinical data are available about large series of cancer patients. Our objective was to determine the usefulness of these preventive sperm freezing protocols. DESIGN: Prospective study. SETTING: University-affiliated private fertility center. PATIENT(S): One hundred eighty-six cancer patients who banked sperm samples at our center before surgery or chemo- or radiotherapy treatments from 1991 to 2004. INTERVENTION(S): Conjugal status, age, type of cancer, treatment, and future use (if any) of the cryopreserved sperm samples for assisted reproduction technology (ART), and cycle results were recorded, analyzed, and compared with a control group. MAIN OUTCOME MEASURE(S): Basic sperm analysis of semen samples from cancer patients prior to freezing, after thawing, and after capacitation for ART. RESULT(S): A total of 320 semen samples were frozen before antineoplasic treatment. Six months later, 27% of the males recovered normal sperm production. From all frozen samples, 8.7% were discarded; the reasons were pregnancy achievement (55%), normal sperm production (28%), and patient death (18%). Finally, 5 IUI cycles and 30 ICSI cycles were done from frozen samples, with 1 and 15 pregnancies, respectively; results were comparable with those obtained in a control group. CONCLUSION(S): A significant number of males who cryopreserved semen samples before receiving antitumoral treatments have employed them. The results obtained showed that this is the strategy of choice, aiming to preserve fertility for the future, because the cost/benefit ratio is favorable. Patients should be counseled accordingly.

Adult↗

PubMed2004

Subfertility, uterine hypoplasia, and partial progesterone resistance in mice lacking the Kruppel-like factor 9/basic transcription element-binding protein-1 (Bteb1) gene.

Progesterone receptor (PR), a ligand-activated transcription factor, is a key regulator of cellular proliferation and differentiation in reproductive tissues. The transcriptional activity of PR is influenced by co-regulatory proteins typically expressed in a tissue- and cell-specific fashion. We previously demonstrated that basic transcription element-binding protein-1 (BTEB1), a member of the Sp/Krüppel-like family of transcription factors, functionally interacts with the two PR isoforms, PR-A and PR-B, to mediate progestin sensitivity of target genes in endometrial epithelial cells in vitro. Here we report that ablation of the Bteb1 gene in female mice results in uterine hypoplasia, reduced litter size, and increased incidence of neonatal deaths in offspring. The reduced litter size is solely a maternal genotype effect and results from fewer numbers of implantation sites, rather than defects in ovulation. In the early pregnant uterus, Bteb1 expression in stromal cells temporally coincides with PR-A isoform-dependent decidual formation at the time of implantation. Expression of two implantation-specific genes, Hoxa10 and cyclin D3, was decreased in uteri of early pregnant Bteb1-null mutants, whereas that of Bteb3, a related family member, was increased, the latter possibly compensating for the loss of Bteb1. Progesterone responsiveness of several uterine genes was altered with Bteb1-null mutation. These results identify Bteb1 as a functionally relevant PR-interacting protein and suggest its selective modulation of cellular processes that are regulated by PR-A in the uterine stroma.

Animals↗