Outcome of tension-free vaginal tape (TVT) procedure in women with stress urinary incontinence--patients' perspective.

This was a subjective review of the success of the tension-free vaginal tape procedure in women with stress urinary incontinence. It was a retrospective study using a postal questionnaire for pre-and postoperative evaluation of symptoms. Ninety-six patients were sent the questionnaire and 71% (n=68) patients filled in the questionnaire. They were asked about pre- and postoperative symptoms. The enquiry was about their satisfaction with the procedure and its cure rate. A visual analogue scale was used to assess results at least 3 months postoperatively. Eighty-three per cent (n = 56) of patients considered their surgery to be successful and were cured without complications; 7% (n = 5) claimed partial success and 10% (n = 7) reported failure. The majority of patients found the TVT procedure to be simple and effective. Hospital stay was short. Their convalescence was short with early return to work. These observations show clear benefit to the patients' health and Health Service economy.

Breaking through artificial selection limits of an adaptive behavior in mice and the consequences for correlated responses.

Previous divergent selection for nest-building behavior at 22 +/- 1 degrees C resulted in a 40-fold difference between the high and the low lines in amount of cotton used to build a nest. Correlated responses to selection indicated positive genetic correlations with body weight, nest-building at 4 +/- 1 degrees C, and litter size and negative genetic correlations with food consumption. At generation 46, the replicate high-selected (High 1 x High 2), randomly bred control (Control 1 x Control 2), and low-selected (Low 1 x Low 2) lines were crossed and the F1 showed significant heterosis for nest-building behavior. Regression of the F3 on the F2 generation gave heritability estimates of 0.16 +/- 0.10 for the high and 0.07 +/- 0.10 for the low cross, revealing a potential to break the selection limit (at least in the high direction), which had been reached at about 20 generations of selection. Indeed, renewed selection resulted in responses in both the high and the low directions of nesting, yielding realized heritabilities of 0.29 +/- 0.02 and 0.30 +/- 0.004, respectively. Replicated renewed selection, using the F3 generation as the base population, in the high direction of nesting resulted in correlated increases in nest-building at 4 +/- 1 degrees C, litter size, and food consumption. Body weight did not change. The positive correlation with food consumption is opposite in sign compared to the original selection experiment. This indicates that the evolutionary potential of a population to adapt to a changing environment not only depends on its current genetic variability in one adaptive trait, but may be constrained by genetic correlations changing over the course of selection.

No evidence for a Y chromosomal effect on alternative behavioral strategies in mice.

This study takes the first step toward testing a Y chromosomal effect on both aggression and thermoregulatory nest-building behavior in mouse lines either bidirectionally selected for short (SAL) and long (LAL) attack latency or high (HIGH) and low (LOW) nest-building behavior. Using reciprocal crosses between SAL and LAL, and between HIGH and LOW, we found no indications for Y chromosomal effects on thermoregulatory nest-building behavior. As for aggression, we confirmed earlier studies on SAL and LAL, i.e., the origin of the Y chromosome influences attack latency, i.e., aggression. However, we did not find indications for a Y chromosomal effect on aggression in the HIGH and LOW lines. Since aggression and nest-building behavior have been shown to be characteristic parameters of two fundamentally different behavioral strategies, the present data underline the improbability of Y chromosomal genes underlying the genetic architecture of alternative behavioral strategies.

Nesting and fitness: lifetime reproductive success in house mice bidirectionally selected for thermoregulatory nest-building behavior.

To test the hypothesis that large, well-built, nests are an important component of fitness, we kept 12 mating pairs of two high-selected, two control, and two low-selected lines, selected for thermoregulatory nest-building behavior, at 22 and 4 degrees C with access to 10 g of cotton to build a nest, for a period of 180 days. Measurements included number of litters born per family, number of young per litter born and surviving up to 40 days of age, nest type built by the parents, and weight gain of the young from weaning (20 days of age) to 40 days of age. In all lines the production and survival of offspring was substantially decreased at 4 degrees C compared to 22 degrees C, but the high-selected lines produced more and better-quality offspring, surviving up to 40 days of age at both temperatures compared to the control and low-selected lines. This indicates that thermoregulatory nest-building behavior and evolutionary fitness are closely associated.

Multiple selection responses in house mice bidirectionally selected for thermoregulatory nest-building behavior: crosses of replicate lines.

Replicate high-selected, control, and low-selected lines were crossed at generation 46 of bidirectional selection for thermoregulatory nest-building behavior. Previous analysis of the lines at their limits had revealed multiple responses to uniform selection, where each of the four selected lines responded differently to reverse selection (Laffan, 1989). The reciprocal F1 crosses showed significant heterosis for nest-building behavior compared to the contemporaneous generations of the parental lines. This pattern of heterosis in all three crosses is consistent with the finding that nest-building behavior in each of the four replicate lines had a different genetic basis, in spite of the phenotypic similarity between the two replicate lines in the high and low direction of nesting. This heterosis effect and the larger number of young weaned in all three crosses compared to their respective contemporaneous generation of the parental lines also support earlier findings that larger nests are closely related to fitness.

A comparison between house mouse lines selected for attack latency or nest-building: evidence for a genetic basis of alternative behavioral strategies.

House mouse lines bidirectionally selected for either nest-building behavior or attack latency were tested for both attack latency and nest-building behavior under identical conditions. Male mice selected for high nest-building behavior had shorter attack latencies, i.e., were more aggressive, than those selected for low nest-building behavior and their randomly bred control lines. Conversely, male wild house mice selected for short attack latency showed more nest-building behavior than those selected for long attack latency when tested at 110 days of age. These findings imply a common genetic basis for control of aggression and nesting and support earlier proposals as to how animals may exhibit fundamentally different responses to environmental challenges, either reacting actively to aversive situations (aggressive and high-nesting animals: active copers) or adopting a passive strategy (nonaggressive and low-nesting animals: passive copers).

Circadian rhythms differ between selected mouse lines: a model to study the role of vasopressin neurons in the suprachiasmatic nuclei.

Mice selected for differences in nest-building behavior differ in the number of arginine-vasopressin (AVP)-immunoreactive neurons in the suprachiasmatic nuclei (SCN). Although previous efforts to link AVP-immunoreactive neurons in the SCN to clock function have failed, we show that differences in several circadian parameters are associated with differences in the number of AVP-immunoreactive neurons between the selected lines. Although an alternative interpretation is discussed, we hypothesize that these neurons may relay timing information from the circadian pacemaker in the SCN for wheel-running activity. In addition, phase-response curves (PRCs) to 15-min light pulses in constant darkness also differ between the selected lines. However, these differences are not associated with the number of the AVP-immunoreactive neurons in the SCN, but are associated with the level of nest-building behavior. Compared to the Brattleboro rat, in which homozygous rats are deficient for AVP in the entire brain, our system, exhibiting a wide range of variability, has more specific utility for studying the role of the output pathways of the SCN in circadian rhythm control.

Differences in the number of arginine-vasopressin-immunoreactive neurons exist in the suprachiasmatic nuclei of house mice selected for differences in nest-building behavior.

Arginine-vasopressin (AVP) is a homeostatic modulator of body temperature during fever and may also be involved in normal body temperature control. In the present study the hypothalamus of mice bi-directionally selected for thermoregulatory nest-building behavior was immunocytochemically labeled for AVP. The low-selected mice had a 1.5-fold higher number of AVP-immunoreactive neurons in the suprachiasmatic nuclei (SCN) compared to the unselected control and the high-selected mice. No differences between the selected lines could be detected in the number of AVP-immunoreactive neurons in the paraventricular nuclei (PVN). The neuroanatomical data suggest a possible role of AVP in the SCN and control of thermoregulatory nest-building behavior. Our selected mice may prove to be a model system to study the role of AVP in the SCN.

Genetic variation for seasonal adaptation in Peromyscus leucopus: nonreciprocal breakdown in a population cross.

The genetic basis for adaptations to the diverse environments encountered by a wide-ranging species should be reflected in the phenotypes of hybrids between differentiated populations. We crossed mice from two ecologically different populations to determine whether adaptations to seasonality in Peromyscus leucopus, the white-footed mouse, display directional dominance or whether they are affected by specific interactions between genes. Connecticut mice (C) have many adaptations to seasonality that are reduced or absent in Georgia mice (G) and that affect both reproductive and thermoregulatory traits. Because these adaptations are cued by photoperiod, temperature, or both, parental and hybrid mice were acclimated to 13 degrees C in either long-day or short-day photoperiod, and several morphological, reproductive, and thermoregulatory traits were measured. Several traits, especially those involved in response to the environment, such as nest size at 13 degrees C, reproductive regression under short-day photoperiod, and molt to winter pelage, showed a non-Mendelian pattern of inheritance. However, there was a pronounced difference between maternal lineages in the F2 generation in that C-maternal F2 mice were less responsive to short-day photoperiod and cold than were the G-maternal F2 mice. Because these two classes of F2 mice are genetically equivalent, this breakdown cannot be explained as a disruption of epistatic gene interactions unless recombination rates are higher in the C-maternal lineage.

Burrowing behavior in wild house mice: variation within and between populations.

Burrowing behavior was assessed on 120 lab-reared house mice (Mus domesticus) derived from five geographic populations representing a north-south cline along the east coast of the United States. Mice were placed individually into Plexiglas containers filled with sand and peat moss, and their burrows were excavated 24 h later. Seven measures were taken and reduced by principal-components analysis to two factors for further analysis. Marked differences existed within, but not between populations, and members of full-sib families built qualitatively and quantitatively similar burrows. The lack of a geographic cline and the apparent high heritability of burrowing behavior do not lend support to its use as a major thermoregulatory adaptation.

Genetic analyses of photoresponsiveness in the Djungarian hamster, Phodopus sungorus.

Endotherms living at temperate and arctic latitudes must adjust their physiology and behavior in order to survive seasonal change. The Djungarian hamster uses photoperiod to cue annual cycles of reproduction and thermoregulation, and its responses to short photoperiod include loss of body weight and change in pelage color. Some individuals do not exhibit these responses when exposed to short days. In this study individual variation in photoresponsiveness is quantified, and four lines of evidence for a genetic component to that variation are provided. First, two separate breeding stocks differed in both the percent of animals responding to a short-day lighting regimen (SD) and in the degree and timing of their response. Second, analysis of variance within and between families of full sibs for a photoresponsive index, PI (body weight loss +2 (molt index -1] following 12 weeks in SD demonstrated a significant family resemblance (intraclass correlation of 0.36 +/- 0.03). Third, heritability estimates from regression of offspring scores on parent scores for body weight loss, molt index and PI after 12 weeks in SD were 0.34 +/- 0.13, 0.36 +/- 0.10 and 0.37 +/- 0.12, respectively, indicating a strong additive genetic component for the three characters. Finally, a significant response occurred after one generation of artificial selection for and against photoresponsiveness.

Photoperiod, temperature and melatonin effects on thermoregulatory behavior in Djungarian hamsters.

Nesting and burrowing activity were measured in hamsters acclimated to either long or short day photoperiod in thermoneutrality and at 10 degrees C. Hamsters build larger nests under short day photoperiod or at 10 degrees C as compared to long day photoperiod or thermoneutrality. Both environmental cues contributed about 50% to a total increase in nest size from 1.8 g cotton/day to 7.7 g cotton/day (long day thermoneutral versus short day at 10 degrees C). Burrowing activity was suppressed by both cold or short day exposure. Daily melatonin injections, effective in inducing physiological short day adjustment under a long day photoperiod, also increased nesting scores. Hamsters which did not respond to short day conditions or to melatonin treatment physiologically lacked behavioral adjustments as well. Collectively, these results demonstrate analogies in the environmental control of physiological thermoregulatory adjustment and nesting behavior. Burrowing activity seems to be more related to reproductive needs than to thermoregulatory requirements in this hamster.

Reproductive responses to variation in temperature and food supply by house mice. I. Mating and pregnancy.

The effects of food restriction upon mating and pregnancy of female house mice were studied at a warm (21 degrees C) and a cold (5 degrees C) temperature to examine the hypothesis that the effects of temperature and food availability are not independent. Analyses of the data showed significant interaction between temperature and food availability for virtually all variables measured, supporting the initial hypothesis. Contingency analysis of mating, fertility, and litter survivorship showed that the interaction influenced not only the percentage of females successfully producing litters, but also the timing of abandonment of reproductive effort by those females that did not have surviving litters. The percentage of females who mated was reduced only in food-restricted females under cold conditions. Both low temperature and food restriction reduced the percentage of mated females that became pregnant. Food-restricted females under cold conditions who did become pregnant tended to kill their litters at birth. The net effect was an interaction between temperature and food restriction that resulted in females reducing or abandoning reproductive effort at progressively earlier stages of the reproductive cycle. The interaction between temperature and food restriction was further displayed in the growth curves of pregnant females, with the reduction of growth by food restriction being greater in the cold.

Reproductive responses to variation in temperature and food supply by house mice: II. Lactation.

Lactating HS/Ibg house mice housed at 21 degrees C and 5 degrees C were assigned to 3 feeding regimes: ad libitum, daily rations of 80% of ad libitum, or 60% of ad libitum beginning on the day that they bore litters. Significant interaction between temperature and food restriction was found for litter survivorship, pup survivorship, litter size, female body weight, and cumulative biomass production. The interaction was due to a magnification of the effects of food restriction at the colder temperature: i.e. mice fed ad libitum were similar at the two temperatures, mice fed the 80% ration differed, and mice fed the 60% ration differed to a greater extent. The dominant response to food restriction was cannibalism by females, which might be associated with the rate of loss in body weight by the female on the days preceding cannibalism of one or more pups. Incidents of cannibalism tended to involve a limited number of pups and to be repeated until a sustainable litter size was reached. In 3 of the food-restricted treatments, females weaned relatively large litters of relatively small pups, but in the most severe treatment (in the group fed the 60% ration at 5 degrees C), the females weaned small litters of large pups. The patterns of cannibalism and variable relative investment in individual pups reflect the aggressive breeding strategy of this classic colonizing species.

Heterosis among lines of mice selected for body weight : 1. Growth.

To examine the effect of selection on levels of heterosis, crosses were made between three groups of six lines of mice, one group unselected (controls) and the other two selected for high (large lines) and low (small lines) 6-week body weight, respectively. The coefficient of inbreeding of each line was about 0.60. Each line was crossed reciprocally to one line from each of the parental groups, as well as producing purebred progeny. Heterosis for 3-week weight, 6-week weight and 3-6 week gain averaged 0.0%, 2.4% and 4.2%, respectively, and was higher for males than for females. Heterosis was more extensive in crosses involving large or control lines than in crosses with small lines. There was no detectable heterosis in several measures of developmental rate, such as age at vaginal opening. Food conversion efficiency and carcass composition were measured on a sample of the animals. Food consumption, gonadal fat pad weight, and hindquarters weight, each expressed as a proportion of body weight, exhibited -4.0%, 5.6%, and 2.3% heterosis, respectively.

Investigation of a common physiological mechanism underlying progesterone-induced and maternal nesting in mice, Mus musculus.

These experiments addressed the possibility that genetic differences in plasma progesterone levels underlie genetic differences observed in maternal nesting (nest building by pregnant mice). Because this hypothesis requires that different circulating levels of progesterone result in a corresponding elevation of nesting, groups of outbred females were treated with varying doses of progesterone, and their nesting was measured. The relation between progesterone dose and nesting was not linear; rather, there appeared to be a threshold dose above which all groups responded similarly. Next, the progesterone levels of four inbred strains and lines selectively bred for differences in nonpregnant (thermoregulatory) nesting were measured directly by radioimmunoassay. The rank order of the inbred strains' and selected lines' progesterone levels did not correspond to the rank order of their nesting. Thus, genetically based differences in maternal nesting are not due to differences in circulating progesterone levels. Other results are presented which suggest a thermo-regulatory mechanism underlying progesterone-mediated maternal nesting which may involve genetic differences in thermal set point.