Intermale aggression and infanticide in aged C57BL/6J male mice: Behavioral deficits are not related to serum testosterone (T) levels and are not recovered by supplemental T

Healthy aged adul (24–26 months of age) and young adult (2–4 months of age) C57BL/6J male mice were assessed for intermale aggression, pup-killing behavior (infanticide), and circulating levels of testosterone (T). When compared to young adult male mice, aged adult males were highly variable in the exhibition of both androgen-dependent behaviors. Significant numbers of aged males exhibited deficits in aggression and pup-killing while other animals were as behaviorally active as their young male counterparts. Assessment of serum T showed that aging did not produce a reduction in levels of the steroid and individual variability in androgen-dependent behavior of aged males was not related to plasma levels of the hormone. When aged non-aggressive and non-killer males were exposed to supplemental T by way of subcutaneously implanted silastic capsules, circulating levels of the steroid were elevated but T-dependent behavior was not recovered. These findings, in combination with those previously reported for copulatory behavior, indicate that the deficits observed in the androgen-dependent behavior of aged male mice cannot be attributed to a breakdown in the production of testicular androgens. While neural refractoriness to T may account in part for deficits in androgen-dependent behavior of aged males, the variability that is observed in the reproductive behaviors of aged male rodents ultimately may be related to other sources of variation such as perinatal environment.     

Alert surveillance of intensive care unit-acquired Acinetobacter infections in a Sicilian hospital

The epidemiological impact of Acinetobacter baumannii nosocomial infections in a Sicilian intensive care unit (ICU) was investigated to determine the Acinetobacter-specific infection rates, to estimate the preventable proportion of Acinetobacter infections, i.e., those resulting from cross-transmission, and to investigate the molecular epidemiology of antimicrobial resistance in Acinetobacter. The impact of Acinetobacter nosocomial infection in the ICU was determined to be 3.0 new cases per 100 admissions. Site-specific rates confirmed that ICU-acquired pneumonia was the most important infection type. The incidence rate, adjusted by the number of patient-days, was 3.3 infections/1000 patient-days. The estimated preventable proportion of A. baumannii nosocomial infections in the ICU was 66.7%. A class 1 integron, characterised by its gene cassette content, was present in all A. baumannii isolates of four different pulsed-field gel electrophoresis types, and was associated significantly with clones implicated in cross-transmission episodes. Furthermore, the same integron was detected in two genetically distinct isolates responsible for recurrent infection in the same patient, suggesting the occurrence of horizontal gene transfer in vivo. Even in an endemic setting with low infection rates, spread of A. baumannii was caused mainly by infection control shortcomings that require appropriate surveillance and control policies.     

Endoscopic Management of Ureteral Strictures: an Update

Purpose of Review

This review focuses on the role of endoscopic treatment of ureteral stricture disease (USD) in the era of minimally invasive surgery.

Recent Findings

There is a relative paucity of recent literature regarding the endoscopic treatment of USD. Laser endopyelotomy and balloon dilation are associated with good outcomes in treatment-naïve patients with short (<?2 cm), non-ischemic, benign ureteral strictures with a functional renal unit. If stricture recurs, repetitive dilation and laser endopyleotomy is not recommended, as success rates are low in this scenario. Patients with low-complexity ureteroenteric strictures and transplant strictures may benefit from endoscopic treatment options, although formal reconstruction offers higher rates of success.

Summary

Formal ureteral reconstruction remains the gold-standard treatment for ureteral stricture disease as it is associated with higher rates of complete resolution. However, in carefully selected patients, endoscopic treatment modalities provide a low-cost, low-morbidity alternative.

     

Postpubertal isolation decreases infanticide and elevates parental care in C57BL/6J male mice

Postpubertal (60 days of age) but not prepubertal (21 days of age) isolation reduced the normal tendency of C57BL/6J male mice to kill newborn pups (infanticide) and instead dramatically elevated their exhibition of parental care (retrieving of young). These effects were time-dependent in that longer durations of isolation (60 days) were more effective than shorter durations (20 days) of individual housing. Postpubertal isolation of male mice with previous killing experience also resulted in a reduction in infanticide and an elevation in parental care, but these effects were not as dramatic as those observed in naive, nonexperienced animals. The findings are discussed in terms of endocrine and neurochemical changes known to accompany isolation in mice.     

Intrauterine position modulates maternal behaviors in female mice

Intrauterine position (IUP), the proximity of a fetus relative to same and opposite sex fetuses, is a reliable predictor of the direction and intensity of social and regulatory behaviors in adult male and female mice. In the present experiment, female Rockland-Swiss (R-S) mice who had resided in utero between two females (OM) and females who had resided between two males (2M) were compared with respect to five indices of maternal behavior: Spontaneous parental responses exhibited toward neonates; nestbuilding during pregnancy; aggression during pregnancy; aggression during lactation; and reproductive/lactation performance. There was no significant difference between 0M and 2M females in their spontaneous parental responses toward neonates or their level of nestbuilding behavior during pregnancy. However, when tested for aggression during pregnancy and lactation, 2M females exhibited aggression on a greater number of test days during pregnancy than did 0M females. Also, during pregnancy and lactation, 2M females displayed more lunges and attacks toward adult male intruders than 0M females. Although 0M females tended to have larger litters than 2M females, the animals did not differ with respect to any other measure of reproductive/lactation performance. Intrauterine position, therefore, modulates some aspects of maternal behavior but apparently not others.     

Resting metabolic rate: a comparison between different measurement methods used in male university students

Introduction

Resting metabolic rate (RMR) is a widely used method to determine an individual's nutritional need. There are different methods of obtaining the RMR values to identify these needs.

Objective

This study aimed to compare the RMR values using two different indirect calorimetry (IC) devices, bioelectrical impedance analysis (BIA), and two predictive equations in a sample of male university students.

Methods

This cross-sectional study analyzed 65 male university students (aged 23.3?±?2.8 years, body mass index 25.78?±?3.98 kg/m²). RMR was obtained using two IC devices (VO2000® and Fitmate PRO^®) and BIA (InBody 570^®), and two predictive equations by Harris and Benedict (Proc Natl Acad Sci 4:370–373, 1918) and FAO/WHO/UNU (Food Agric Organ 1:103, 2001).

Results

The Bland–Altman (B&A) plot demonstrated considerable differences between the two gold standard methods, VO2000^® and Fitmate PRO^®, and BIA, with a mean difference of 7.8 and 5.7%, respectively. The B&A plot presented the lowest difference between the two IC devices with a mean difference of 2.1%. The B&A plot also showed a low difference between the two IC devices and predictive equations, with values ranging from ?1.3 to ?3.6%. In turn, the B&A plot between BIA and the predictive equations comprised approximately ???9.2% of the mean difference. The analysis of variance (ANOVA) demonstrated no significant differences between the measurements (p?>?0.05).

Conclusion

Based on the results, InBody 570^® underestimates the reference values for RMR in two different IC devices as well as in the predictive equations. Although no significant differences were observed between ANOVA comparisons, the RMR values obtained using BIA should be analyzed with caution. The absence of sophisticated devices for RMR analysis indicates the need to use the FAO/WHO/UNU (Food Agric Organ 1:103, 2001) equation, which presented a lower difference compared with that of the gold standard measurements in male university students.

     

Evaluation of the microscopic observation drug susceptibility assay for detection of Mycobacterium tuberculosis resistance to pyrazinamide

The microscopic observation drug susceptibility assay (MODS) was evaluated to determine susceptibility to pyrazinamide in Mycobacterium tuberculosis, and compared with the broth microdilution method (BMM), absolute concentration method (ACM), and pyrazinamidase (PZase) determination. We tested 34 M. tuberculosis clinical isolates (24 sensitive and eight resistant to pyrazinamide) and the control strains M. tuberculosis H37Rv (ATCC 27294) and Mycobacterium bovis AN5. The MODS, BMM, ACM and PZase determination provided results in average times of 6, 18, 28 and 7 days, respectively. All methods showed excellent sensitivity and specificity (p <0.05). Of the methods studied, the MODS proved to be faster, efficient, inexpensive, and easy to perform. However, additional studies evaluating the MODS in differentiating pyrazinamide-resistant and pyrazinamide-susceptible M. tuberculosis must be conducted with a larger number of clinical isolates.