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[The involutional age from the viewpoint of the gynecologist].

Besides the normal aging processes, which affect all human beings, regardless of their gender the involutional years of women have a number of special characteristics. These are based on the fact, that one group of organs-the reproductive system - hold their function earlier than the others. Because of this fact the involution of women ist basically different from that of men. During these years she often require therapeutic help by a physician not only for drug therapy but also psychologically. The drug-therapy seems to be relatively simple: balance of the oestrogen deficit. But today the oestrogen therapy became more difficult and has to be adjusted individually. The decision has to be made in regard to the type of hormone, the dose, the time sequence, the question of the gestagen component, the risk for malignancy, the effect on clothing and vessels etc. Old and new types of therapy including diet, tea, climate and bathing cures, tranquilizers, drugs for the autonomic nervous system, homeopathic therapy, acupuncture etc. also have their place. We will discuss these questions in the afternoon session extensively since the involutional years of women from the view of the gynaecologists are a very interesting and important field of medicine still for therapy and research.

Blood Pressure

Impact of genomic selection for disease resistance on the spread of infection in a simulated aquaculture population.

BACKGROUND: In aquaculture, selection for disease resistance is typically based on mortality records from challenge tests performed on relatives of selection candidates. However, commercial success depends on limiting disease transmission, particularly the incidence and severity of outbreaks. It remains unclear whether selecting for lower mortality also reduces disease transmission. Both these outcomes are influenced by three underlying epidemiological host traits: susceptibility, infectivity, and infection-induced mortality. This simulation study evaluated the impact of genomic selection against mortality on disease transmission in a salmon population exposed to a pathogen with a fast transmission rate. METHODS: Mortality was assumed to be recorded on sibs of selection candidate, either as binary dead/alive status or as time to death during cohabitation/bath challenge tests. Phenotypes were simulated using a stochastic compartmental Susceptible-Infected-Removed epidemiological model, with genetic variation for the three underlying traits. Scenarios were explored by varying the genetic correlations between the three underlying traits. Challenge test designs varied in the number of groups, group sizes, and family distribution across groups. For comparison, a reference scenario with direct selection on the underlying traits was included. Genomic selection was applied over 10 discrete generations, and its impact on disease transmission was assessed using the basic reproductive ratio (R0). RESULTS: When selection was based on dead/alive status, R0 was highly sensitive to both the genetic correlations between the three underlying traits and the challenge test design. In contrast, selection based on time to death consistently reduced R0 across all scenarios (often to below 1 within four generations), regardless of trait correlations or test design. Selection on time to death primarily produced fish with reduced susceptibility to infection, while selection on dead/alive status produced fish with increased resistance and endurance to infection, delaying onset of infection or death without necessarily limiting transmission. Direct selection on the underlying epidemiological traits was the most efficient approach to reduce both mortality and transmission. CONCLUSIONS: Genomic selection for disease resistance, when measured as time to death in cohabitation or bath challenge tests conducted until mortality naturally levels off, reduces both mortality and disease spread. Breeding programs may benefit from challenge test designs that enable estimation of genetic parameters for the underlying traits affecting disease transmission and survival.

Animals

The evolution of sexual reproduction as a repair mechanism. Part I. A model for self-repair and its biological implications.

The theory is presented that the sexual process is a repair mechanism which maintains redundancy within the sub-structure of hierarchical, self-reproducing organisms. In order to keep the problems within mathematically tractable limits (see Part II), a simple model is introduced: a wheel with 6 spokes, 3 of them vital and 3 redundant, symbolizes the individual (cell or organism). Random accidents destroy spokes; the wheels replicate at regular cycles and engage periodically in pairing and repair phases during which missing spokes are copy-reproduced along the intact spokes of the partner wheel. The hierarchical structure of such a system is analysed and an 'autonomous unit' is defined: this is the unit of minimal hierarchical complexity which is capable of perpetuating autonomously all higher and all lower levels of the hierarchy; this is the central unit of selection. Four basic, physical parameters are isolated which determine the essential features of any eucaryotic life cycle: 1. The number of levels of the hierarchy (unicellular, multicellular, colonial, etc.); 2. the relation between the phases of replication (asexual generations) and repair (sexual generations); 3. the duration of potential repair (haplo-diplo-phase); 4. the position of the sexual partners within the hierarchy (selfing, monecy, dioecy, reproductive individuals within colonies, etc.). The evaluation of fitness components is considered in relation to trends of reproductive patterns in evolution.

Animals

[Effect of glycosides of Tripterygium wilfordii Hook on the reproductive system and major organs of male rats].

Spermatogenesis and turnover of basic nuclear protein synthesis in late elongated spermatids of rat testis were found to be significantly inhibited by glycosides of Tripterygium wilfordii Hook (T II) at a daily dosage of 10 mg/kg for 7 or 13 weeks and 20 mg/kg for 4 or 10 weeks. The number of spermatozoa in the epididymis was found to be reduced and the remaining spermatozoa deformed, showing head swelling, head and tail separation and severe curling of the middle piece. These changes differed from those effected by gossypol treatment. The formazan deposits of sperm mitochondrial enzyme reactions were also reduced. Activities of several enzymes in the heart, liver and kidney were not obviously affected, except for an enhancement of SDH activity in tissues of all 3 organs and ALP in renal tubules, with a slight decrease of ALP in the brush-borders of proximal renal tubules arising as an adaptation to T II toxicity.

Animals

Model fitting and projection of the AIDS epidemic.

Previously it was possible to fit detailed models to incidence data (for example, of AIDS) only by trial and error and good judgment; the large number of parameters obstructed optimization of, for example, the (approximate) likelihood. Here, we analyze a model for the spread of AIDS in a homosexual population and identify a minimal set of primary components that dictate the dynamics of the Model: the initial growth rate theta, the basic reproductive ratio R0, and the heterogeneity coefficient S. It is then shown that it is sufficient to maximize the likelihood over these three primary components; further maximization over the remaining secondary parameters does not produce a significant improvement in the fit or affect the projection of the epidemic. This method also allows construction of confidence limits for the projected incidence curve, allowing us to quantify the uncertainties associated with such model fitting procedures. The method is tested on simulation data to analyze how the accuracy of estimates and projections changes as we gain more data.

Acquired Immunodeficiency Syndrome

Numbers and diameters of motoneurons and myelinated axons in the facial nucleus and nerve of the albino rat.

The number and diameter of the motoneurons in serial sections of the facial nucleus in the albino rat were estimated using a photograph-camera lucida technique for counting and measuring cells in conjunction with a systematic section method for sampling the population. The mean diameter of facial motoneuron nucleoli was also estimated. Total cell counts were estimated using two formulas, one a basic count and the other the basic count corrected for split nucleoli errors. The mean motoneuron diameter is 33-93 micronm (+/- 6-18 micronm S.D.). The number and diameter of myelinated axons in both the facial nerve and its cutaneous auricular branch at the level of the stylomastoid foramen were estimated. There are 5353 myelinated axons in the facial nerve, with a mean diameter of 2-74 micronm, and 627 myelinated axons in the cutaneous auricular branch with a mean diameter of 1-47 micronm. The accuracy and reproductibility of results using the photograph-camera lucida technique for counting and measuring cells and the systematic section method of sampling are compared with those of the methods used by previous investigators. The accuracy of results obtained for estimates of the total cell count using the formulas for the basic count and the basic count corrected for split nucleoli are also compared.

Animals

Mechanisms regulating the ovarian cycle in the frog Rana cyanophlyctis: effect of unilateral ovariectomy, season, feeding, human chorionic gonadotrophin, and estradiol-17 beta.

Effects of 30-day unilateral ovariectomy (ULO) on compensatory ovarian hypertrophy (COH) was studied in adult frog Rana cyanophlyctis in relation to reproductive phase/season, feeding, and treatment with human chorionic gonadotrophin (HCG) or estradiol-17 beta. Compensatory growth of the remaining ovary was assessed in terms of weight as well as changes in the dynamics of the pool sizes of different oocytes viz., first growth phase (FGP), medium-sized second growth phase (MSGP), large-sized second growth phase (LSGP), and atretic oocytes. The frogs were fed with live guppies 6 days a week. The effect of underfeeding on COH was studied in the frogs fed once a week. The ovaries removed at operation and those of the sham-operated frogs were used for comparison (controls). COH occurred in both pre- and postbreeding phases (February and November, respectively). In both instances follicular atresia was greatly reduced. In February, COH was due to recruitment of both MSGP and LSGP oocytes. The number of these oocytes increased significantly over controls, and the ovarian weight nearly doubled. However, in November COH occurred because of an increase in FGP oocytes and therefore total oocytes, but there were no changes in the ovarian weights. Administration of 20 IU HCG (6 days a week) had no influence on the basic pattern of COH-response exhibited by the remaining ovary in relation to reproductive phase/season, but it increased the recruitment of oocytes, i.e., FGP oocytes in November and SGP oocytes in February. Follicular atresia was drastically reduced with HCG. Underfeeding or treatment with estradiol-17 beta abolished the COH in both February and November.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Population dynamics of mosquito-borne disease: persistence in a completely heterogeneous environment.

We investigate the persistence of a mosquito-borne disease (malaria) in a system where mosquitoes and hosts are grouped in patches containing any number of individuals. A mosquito from any one of vector patches can bite, and take blood meals, in any one of m host patches. We confirm our earlier result (C. Dye and G. Hasibeder, 1986, Trans. R. Soc. Trop. Med. Hyg. 80, 69-77) that nonhomogeneous host selection by mosquitoes leads to basic reproductive rates (which measure the persistence of infection in the system) greater than or equal to those obtained under uniform host selection. We find, in addition, that strong associations between particular groups of mosquitoes and hosts lead to still higher basic reproductive rates. Exacting fieldwork would be required to find out how much higher.

Animals

Estimation of the dynamics and rate of transmission of classical swine fever (hog cholera) in wild pigs.

Infectious diseases establish in a population of wildlife hosts when the number of secondary infections is greater than or equal to one. To estimate whether establishment will occur requires extensive experience or a mathematical model of disease dynamics and estimates of the parameters of the disease model. The latter approach is explored here. Methods for estimating key model parameters, the transmission coefficient (beta) and the basic reproductive rate (RDRS), are described using classical swine fever (hog cholera) in wild pigs as an example. The tentative results indicate that an acute infection of classical swine fever will establish in a small population of wild pigs. Data required for estimation of disease transmission rates are reviewed and sources of bias and alternative methods discussed. A comprehensive evaluation of the biases and efficiencies of the methods is needed.

Animals

Cytologic features of oocytes in the adult human ovary.

A broad survey of the cytologic features of follicular oocytes from sections of adult ovaries from donors with normal menstrual cycles, from patients with polycystic ovarian disease, and from patients treated with estrogen and progesterone for gynecologic disorders with no apparent ovarian pathology has been made in this study. On the basis of light microscopic observations, four basic types of oocytes could be recognized: (1) oocytes with nuclei containing diffused or filamentous chromatin, (2) oocytes with metaphase I chromosomes or an extruded polar body, (3) oocytes with nuclei possessing massive clumps of chromatin frequently associated with the nucleolus, and (4) degenerating oocytes with no distinguishing cytologic features. The numbers of oocytes in these different groups varied with the reproductive state of the donors: 34 to 35% were type 1 during proliferative and secretory phases; mature oocytes type 2 were 3.3%, and were found only during the late proliferative phase; and 41 to 46% were type 3 during both phases of the menstrucal cycle. Large numbers of oocytes from polycystic ovaries (77%) and from ovaries of patients treated with steroids (86%) were degenerating and frequently contained massive clumps of chromatin material associated with the nucleolus.

Adult

[Pregnancy, labor, and puerperium: concepts and practices of midwives in the state of Morelos].

In Mexico a combined type of care for the health-sickness phenomenon exists, where three systems interact: domestic, academic and traditional medicine. In relation to reproductive health, in the state of Morelos approximately 50 per cent of women in rural areas receive attention from traditional birth attendants, who make up one of the principal resources of traditional medicine. The goal of this study was to gather knowledge about and describe the concepts, resources and practices used by traditional birth attendants in their care during pregnancy, birth and puerperium; and likewise to determine their socio-demographic characteristics, their geographic distribution, their number and the level of training which they possess. A census based on three sources was carried out in which information about seven basic variables was sought. This information was completed with structured interviews with key informants which allowed the definition of a profile of the different types of traditional birth attendants according to the population they care for and the resources they use. The most relevant results indicate that 630 traditional birth attendants are distributed throughout the 32 municipalities of the state, with an average age of 52 years and 50 per cent having attended training courses. 17.5 per cent fall within the category of traditional birth attendant, 50 per cent are trained empiricists and 11.6 per cent are non-trained empiricists. The 20 per cent did not fit this typology. The strong social and cultural identification that exists between traditional birth attendants and their patients indicates the need to incorporate this valuable resource in rural reproductive health programs.

Adult

The invasion, persistence and spread of infectious diseases within animal and plant communities.

Recent theoretical and empirical studies of the population biology of infectious diseases have helped to improve our understanding of the major factors that influence the three phases of a successful invasion, namely initial establishment, persistence in the longer term and spread to other host communities. Of central importance in all three phases is the magnitude of the basic reproductive rate or transmission potential of the parasite. The value of this parameter is determined by a variety of biological properties of the association between an individual parasite and its host and the interaction between their populations. The recent epidemic of acquired immunodeficiency syndrome (AIDS) in North America and Europe is employed to illustrate the factors that promote disease establishment and spread. The frequency distribution of the number of different sexual partners per unit of time within homosexual communities is shown to be of central importance with respect to future trends in the incidence of AIDS. Broader aspects of pathogen invasion are examined by reference to simple mathematical models of three species associations, which mirror parasite introduction into resident predator-prey, host-parasite and competitive interactions. Many outcomes are possible, depending on the values of the numerous parameters that influence multi-species population interactions. Pathogen invasion is shown to have far-reaching implications for the structure and stability of ecological communities.

Acquired Immunodeficiency Syndrome

[Variations in reproductive capacity, gonotrophic cycle and longevity of Anopheles sinensis infected by Brugia malayi larvae].

Under the experimental conditions of 26 +/- 10 degrees C, relative humidity 70-80%, 100 +/- 20 Lux and photoperiod 16 hours/day and using a membrane feeding method, the development of filarial larvae and the variations in reproductive capacity, gonotrophic cycle and longevity of An. sinensis infected with microfilariae of Brugia malayi were observed. The infection rate and infection intensity of filarial larvae in An. sinensis increased with the microfilarial density in the blood meal from 50 to 150 mf/20 microliters. The mature rate and IEI decreased when the density rose to 200 mg/20 microliters. The concentration ratio of mf in blood by An. sinensis was 1.2-1.4. In the 3rd gonotrophic cycle, the feeding ratio of infected mosquitoes became lower when the mf density rose to 150 mf/20 microliters, but the infection of filarial did not affect the number of oviposition, the regularity of egg-production activity and the hatching rate of eggs, while the quantity of egg-production increased when the mf density was 150 mf/20 microliters. The egg-production rate, and gonotrophic cycle were not basically influenced by filarial larvae infection. The multifeeding ratio was 16.7-48.4% in An. sinensis. The longevity of An. sinensis was extended by infection with mf density of 100 mf/20 microliters and shortened in infection with mf density of 200 mf/20 microliters. The authors conclude that "Brugia malayi-Anopheles sinensis" is a highly adapted "pathogen-vector" system.

Animals

[Progress and change in geriatric gynecological surgery (author's transl)].

Two periods of geriatric gynecological surgery (1947-1959 and 1960-1972) at the University Women's Hospital in Hamburg-Eppendorf were compared in regard to the age of the patient, surgical indications, surgical procedure, anesthetic technique, preoperative and postoperative morbidity, length of hospitalization and mortality rate. During a period of 26 years, 1514 women over the age of 60 were treated surgically. During the first period, 489 women were treated, and in the second period, 1,025. This 109.6% increase has been confirmed statistically. The increase in geriatric surgical cases stems basically from the increase in the number of surgical patients over the age of 70. The increase in breast carcinoma during the second period (from 43 to 348 operations) is most conspicuous. This is an increase of 809.3%. On the basis of this disproportionately large increase in breast surgery, more women were treated surgically in the University Women's Hospital in Hamburg-Eppendorf for breast carcinoma during the second period, than for carcinoma of the reproductive organs. Vulva carcinoma and craurosis vulvae were also more frequently considered to be an indication for surgical treatment. The total number of women who were surgically treated for prolapsed uterus and vagina remained more or less constant. In the analyzing the surgical records, it should be emphasized that, in the second observation period, two-thirds of these cases were treated by performing a vaginal hysterectomy with anterior and posterior vaginoplasty. For older patients, palliative surgical measures for prolapsed uterus and vagina were abandoned in favor of more definitive methods. The postoperative morbidity and mortality rate remained more or less constant for both periods. The postoperative period of hospitalization was slightly longer while the preoperative period was slightly shorter. The statistically confirmed increase in geriatric surgery during the last 13 years at the University Women's Hospital in Hamburg-Eppendorf clearly shows how important geriatric surgery has become. The immediate consequences are an increased workload for physicians, nursing staff and physical therapists.

Age Factors

Box-Jenkins modeling of chronological series of twin births and single births.

A time-series analysis by Box-Jenkins modeling of the monthly observations of twin births and singleton births was attempted. The study is population based. The single-birth series has been matched to the twin-birth series for maternal birth cohort, parity of the twin birth, and residence of the parents. Three-hundred forty-one twin pairs and 340 singleton births were grouped into chronological series spanning 72 months of observation. Univariate and bivariate time-series analyses were used. Box-Jenkins modeling shows that both series share the same basic demographic and reproductive risk factors, such as ovulation and conception rates, abortions, sexual intercourse, and the less well-known random events that determine the time of delivery. These factors are randomly related to both birth processes but exert a more important influence on twin births. Beyond these crude features, twin- and single-birth series differ by the frequency of their seasonal cycle. Twin births show low-frequency variations because of a rather limited number of factors that impinge markedly on the twinning process. Single births are subjected to higher frequency variations that can be ascribed to a greater number of structuring factors, the action of which is less pervasive. Only the January peak is common to both types of births. Aside from the common features, the bivariate analysis shows that both series of births are independent, neither being related to the other. It is concluded that the subtle structuring of both processes is largely distinct. The large fraction of the unaccounted variation of each birth process (about 70%) suggests that most of the variation is due to as yet unidentified factors. The search for environmental and geocosmic factors at the origin of conception and confinement should be considered in future undertakings.

Birth Order

Proteinases and their inhibitors in cells and tissues.

A large body of evidence has been assembled to indicate the substantial importance of proteolytic processes in various physiological functions. It has recently become clear too that endo-acting peptide bond hydrolases provisionally characterized and classified at present as serine, cysteine, aspartic and metallo together with unknown catalytic mechanism proteinases sometimes act in cascades. They are controlled by natural proteinase inhibitors present in cells and body fluids. In the first part of the present monograph the author was concerned to present an overview on the morphological and physiological approach to localization, surveying reaction principles and methods suitable for visualization of proteolytic enzymes and their natural and synthetic inhibitors. In the second part the roles played by proteinases have been summarized from the point of view of cell biology. The selection of earlier and recent data reviewed on the involvement of proteolysis in the behavior of individual cells reveals that enzymes, whether they be exogeneous or intrinsic, can be effective and sensitive modulators of cellular growth and morphology. There exists a close correlation between malignant growth and degradation of cells. It appears likely that as yet unknown or at least so far inadequately characterized factors that influence the survival or the death of cells may turn out to be proteinases. The causal role of extracellular proteolysis in cancer cell metastases, in stopping cancer cell growth and in cytolysis remains for further investigated. Ovulation, fertilization and implantation are basic biological functions in which proteolytic enzymes play a key role. The emergence of new approaches in reproductive biology and a growing factual basis will inevitably necessitate a reevaluation of present knowledge of proteolytic processes involved. The molecular aspects of intracellular protein catabolism have been discussed in terms of the inhibition of lysosomal and/or non-lysosomal protein breakdown. Peptide and protein hormone biosynthesis and inactivation are still at the centre of interest in cell biology, and a number of proteinases have been implicated in both processes. A number of conjectures partly based on the author's own work have been discussed which suggest the possibility of the involvement of proteolysis in exocytosis and endocytosis. The author's optimistic conclusion is that through the common action of biochemists, cell biologists, cytochemists, and pharmacologists the mystery of cellular proteolysis is beginning to be solved.

Animals

A general model for the African trypanosomiases.

A general mathematical model of a vector-borne disease involving two vertebrate host species and one insect vector species is described. The model is easily extended to other situations involving more than two hosts and one vector species. The model, which was developed from the single-host model for malaria described by Aron & May (1982), is applied to the African trypanosomiases and allows for incubation and immune periods in the two host species and for variable efficiency of transmission of different trypanosome species from the vertebrates to the vectors and vice versa. Equations are derived for equilibrium disease prevalence in each of the species involved. Model predictions are examined by 3-dimensional phase-plane analysis, which is presented as a simple extension of the 2-dimensional phase-plane analysis of the malaria model. Parameter values appropriate for the African trypanosomiases are derived from the literature, and a typical West African village situation is considered, with 300 humans, 50 domestic animals and an average population of 5000 tsetse flies. The model predicts equilibrium prevalences of Trypanosoma vivax, T. congolense and T. brucei of 47.0, 45.8 and 28.7% respectively in the animal hosts, 24.2, 3.4 and 0.15% in the tsetse vectors, and a 7.0% infection of humans with human-infective T. brucei. The contribution to the basic rate of reproduction of the human-infective T. brucei is only 0.11 from the human hosts and 2.54 from the animal hosts, indicating that in the situation modelled human sleeping sickness cannot be maintained in the human hosts alone. The animal reservoir is therefore crucial in determining not only the continued occurrence of the disease in humans, but its prevalence in these hosts as well. The effect of changing average fly density on equilibrium disease prevalences is examined, together with the effect of seasonal changes in fly numbers on disease incidence. In a seasonal situation changes in fly mortality rates affect both future population size and infection rate. Peak disease incidence lags behind peak fly numbers, and that in the less favoured host lags behind that in the more favoured host. Near the threshold fly density for disease transmission disease incidence is more changeable than at higher fly densities and may even exceed equilibrium prevalence at the same average fly density (because most hosts are susceptible at the time that fly numbers begin their annual increase).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals

Perinatal mortality and morbidity in rural West-Java, Indonesia. Part I: Vital statistics based on cross-sectional surveys.

The first part of this article gives the summary result of 4 cross-sectional surveys conducted in 3 rural villages in West Java. It is expected that these surveys provide the researchers with more precise data on perinatal mortality and its associated causes in order to plan and implement the Tanjungsari Intervention Study (1986-1990). This comprises a mapping and numbering survey, and a census survey. Based on a sampling frame of 7964 houses, a systematic sample (one in eleven) was drawn for the Household and for the Married Women Surveys. The survey results yield some basic demographic indicators, occupational information and data on education. Also data on environmental health and vital statistics are presented. It is shown that the crude birth rate is 40 per thousand and that the estimated infant mortality rate reaches a figure of 120%. Furthermore, during individual interviews data was collected on characteristics, attitudes habits as well as on reproductive behaviour, of all married women under 50 years of age.

Adolescent