Long-term day-and-night rotating shift work poses a barrier to the normalization of alanine transaminase

To evaluate the impact of day-and-night rotating shift work (RSW) on liver health, we performed a retrospective analysis of the association between long-term RSW exposure and the normalization of plasma alanine transaminase (ALT) levels over a five-year period. The data from physical examinations, blood tests, abdominal sonographic examinations, personal histories, and occupational records were collected from a cohort of workers in a semiconductor manufacturing company. The sample population was divided into three subgroups for analysis, according to self-reported shift work status over the five-year interval: persistent daytime workers, workers exposed intermittently to RSW (i-RSW), and workers exposed persistently to RSW (p-RSW). Records were analyzed for 1196 male workers with an initial mean age of 32.5 years (SD 6.0 years), of whom 821 (68.7%) were identified as rotating shift workers, including 374 i-RSW (31.3%) and 447 p-RSW workers (37.4%). At the beginning of the follow-up, 275 were found to have elevated ALT (e-ALT): 25.1% daytime workers, 23.0% i-RSW workers, and 21.3% p-RSW workers (p?=?0.098). Of those with e-ALT at the beginning, 101 workers showed normalized serum ALT levels at the end of five-year follow-up: 40 (10.7%) of 375 daytime workers, 32 (8.6%) of 374 i-RSW workers, and 29 (6.5%) of 447 p-RSW workers (p?=?0.016). Compared with the workers having persistent e-ALT at the end of follow-up, the workers normalized serum ALT levels had significantly lesser exposures to RSW during follow-up. By performing multivariate logistic regression analyses, and comparing with the persistent daytime co-workers, after controlling for confounding variables (age, occupational factors, educational levels, lifestyle factors, metabolic syndrome, hepatovirus infection, and fatty liver), analysis indicated that the workers exposed to p-RSW were 46% less likely (OR, 0.54; 95% CI, 0.30–0.95; p?=?0.03) to attain normal ALT levels within a five-year interval. These observations demonstrate that persistent day-and-night RSW pose a vigorous obstacle to the normalization of e-ALT among workers with preexisting abnormal liver function. We suggest that workers and managers approach with caution the consideration of assigning or accepting long-term day-and-night RSW when an employee health screening shows evidence of abnormal liver function.     

Influence of male presence on clutch size in Schistocerca vaga Scudder (Orthoptera: Acrididae)

Male Schistocerca vaga produce a pheromonal factor that causes increase in clutch size. Females exposed to males, but prevented from physically contacting or copulating with them, produce significantly more eggs (P < 0.01) than virgins not exposed to any males at all. There is no significant difference between the clutch sizes of such exposed females and those of females which are allowed both physical contact and copulation. Castration does not abolish this effect of male presence on clutch size. Visual exposure alone does not enhance clutch size, whereas olfactory exposure, with or without concomitant physical contact, leads to increased clutch size.     

A revision of the ant genus Mystrium in the Malagasy region with description of six new species and remarks on Amblyopone and Stigmatomma (Hymenoptera,Formicidae, Amblyoponinae)

The genus Mystrium is revised for the Malagasy region. Six species, Mystrium barrybressleri sp. n., Mystrium labyrinth sp. n., Mystrium eques sp. n., Mystrium mirror sp. n., Mystrium shadow sp. n., and Mystrium janovitzi sp. n. are described as new. Two existing names, Mystrium fallax Forel and Mystrium stadelmanni Forel, are synonymized with Mystrium voeltzkowi Forel and Mystrium mysticum Roger, respectively. All recognized species, including species outside of the Malagasy region, are assigned to one of the three newly proposed species groups. The associations between existing names and males are reexamined, and males of eight of the ten Malagasy species are described or redescribed. The taxonomic history of Mystrium highlights the importance of using unique identifiers when designating type specimens and the use of deposited vouchers in phylogenetic and ecological studies. Keys to species for workers, queens, and males are provided. Furthermore, a neotype for Mystrium mysticum is designated, as well as lectotypes for Mystrium camillae Emery, Mystrium rogeri Forel, Mystrium fallax Forel, Mystrium oberthueri Forel, Mystrium stadelmanni Forel, and Mystrium voeltzkowi Forel. Stigmatomma gingivale (Brown) is reassigned to Amblyopone as comb. rev. and Amblyopone awa Xu & Chu, Amblyopone kangba Xu & Chu, Amblyopone meiliana Xu & Chu, and Amblyopone zomae Xu & Chu are transferred to the genus Stigmatomma as comb. n.     

THE EFFECT OF AEROBIC CONTINUOUS AND INTERVAL TRAINING ON LEFT VENTRICULAR STRUCTURE AND FUNCTION IN MALE NON-ATHLETES

Exercise plays an important role to improve cardiovascular performance. The aim of this study was to compare the effect of aerobic continuous and interval training on the left ventricular structure and function. Twenty untrained healthy male students (aged 18-22 years) were randomly divided into two groups: continuous (C; n = 10) and interval (I; n = 10). The training programme consisted of countryside jogging for 45 min during 8 weeks three times a week at 70% of maximum heart rate (MHR). In each session group C was jogging for 45 min and in group I jogging was performed in 5 nine-minute stages with a four-minute inactive rest between them. M-mode, 2-dimensional, colour and Doppler transthoracic echocardiography were performed, during resting conditions, before and after the training period. After 8-week training the end diastolic diameter, systolic blood pressure and diastolic blood pressure in groups C and I, and the posterior wall thickness and the end systolic diameter in group I showed no significant difference (P > 0.05). On the other hand, the percentage of ejection fraction and shortening fraction in groups C and I, the end systolic diameter and the posterior wall thickness in group C and the interventricular septum thickness in group I demonstrated a significant difference (P ≤ 0.05). Comparing the two groups, only the value of the interventricular septum thickness was significant (P ≤ 0.05). In general, eight-week aerobic continuous and interval training can affect left ventricular structure and function.     

Determination of adenosine triphosphate in human semen to estimate the fertilizing potential and to quantify sperm antibodies

The measurement of the ATP content of fresh semen is as accurate as the estimation of sperm motility by conventional methods in discriminating between semen of fertile versus subfertile men. The ATP content of frozen thawed donor semen is correlated with the probability of conception per cycle of insemination. Exact quantification of cytotoxic sperm antibodies in serum is possible with the adenosine-triphosphate-release-cytotoxicity test, since measurement is free of the bias of microscopic examination. The procedure has been simplified by testing only one serum dilution and calculating the ‘sperm toxicity index’.     

Age differences in social interactions of young males in a chimpanzee unit-group at the Mahale Mountains National Park,Tanzania

The behavior and social interactions of young male chimpanzees were studied in relation to their age change. The data were obtained at the Mahale Mountains National Park, during a four-month period in 1986. Early adolescent males, becoming independent of their mothers, spend a long time near adults of both sexes. Late adolescent males are not tolerated by the senior males. Although such animals do not stop traveling together with their seniors, they are separated from the other members including the males of their own age class, and each of them lives a relatively lonely life. Where seniors are not nearby, they perform charging displays in front of estrous females. Young adult males tend to remain in the proximity of the alpha male, and can associate with their seniors without pant-grunting. Although some young adult males dominate over some senior males, increasingly performing charging displays, they do not appear to be permitted to associate intimately with their seniors; they are not yet considered to have attained social maturity. Prime and senior males are strongly bonded with one another, being able to associate intimately with those of their own or senior age classes including the alpha male. A young adult male's rise in rank is not connected with joining the “adult male-cluster,” nor does a senior male's decline necessarily means his dropping out from the cluster: the social position of male chimpanzees cannot be understood solely from their agonistic dominance rank. The alpha male plays a leading part in integrating the males of the unit-group. Young adult males and their seniors tend to associate most frequently with him, and all the males of the early adolescent or senior age classes pay attention to his movements.     

Advanced weathering cracks as an improvement on split-line preparations for analysis of structural orientation in compact bone.

Weathering cracks have been demonstrated to be equivalent to split-lines in compact bone. The amount of cracking becomes more extensive with time. Advanced weathering cracks have the potential for giving more complete information on orientation patterns than split-lines. They can also be superior in accuracy and objectivity of results obtained, in preserving the original condition of the bone, and in elimination of much of the work involved in making split-line preparations.     

Metabolic divergence between sibling species of cichlids Pundamilia nyererei and Pundamilia pundamilia

This study compared Pundamilia nyererei and Pundamilia pundamilia males in routine metabolic rate (R_R) and in the metabolic costs males pay during territorial interactions (active metabolic rate, R_A). Pundamilia nyererei and P. pundamilia males housed in social isolation did not differ in R_R. In contrast to expectation, however, P. nyererei males used less oxygen than P. pundamilia males, for a given mass and level of agonistic activity. This increased metabolic efficiency may be an adaptation to limit the metabolic cost that P. nyererei males pay for their higher rate of aggressiveness compared to P. pundamilia males. Thus, the divergence between the species in agonistic behaviour is correlated with metabolic differentiation. Such concerted divergence in physiology and behaviour might be widespread in the dramatically diverse cichlid radiations in East African lakes and may be an important factor in the remarkably rapid speciation of these fishes. The results did not support the hypothesis that higher metabolic rates caused a physiological cost to P. nyererei males that would offset their dominance advantage.     

A comparison of in vitro and in vivo estimates of the viability of Taenia pisiformis eggs aged under controlled conditions, and their ability to immunise against a challenge infection

Storing the eggs of T. pisiformis for periods of 0 to 9 days at a temperature of 36–38°C and relative humidity of 87–93 % revealed at least 4 stages in the ageing process. Firstly, a stage in which eggs hatched and activated in vitro and were also fully infective for rabbits. Secondly, a stage in which eggs hatched and activated in vitro but underwent only partial development in rabbits. Thirdly, a stage in which eggs hatched and activated in vitro, and presumably therefore in vivo, but no evidence of infection could be found when they were fed to rabbits. Fourthly, a stage in which eggs either did not hatch, or if they did hatch, the oncosphere was rapidly digested. In vitro techniques for assessing viability of T. pisiformis eggs were not a reliable guide to their infectivity for rabbits. ‘Senescent’ eggs, that is eggs which produced evidence of early infection in rabbits but did not complete their development to cysticerci, failed to produce immunity to challenge infection with T. pisiformis eggs.