Twelve-month resistance and impact exercise program or risedronate provides a relative benefit to hip bone structure in postmenopausal women: results from a randomized controlled trial.

Bone strength estimates are important for fracture prevention. This study compared bone strength changes in postmenopausal women with low bone mass who were assigned to 12 months of exercise, a bone medication, or control. Exercise and bone medications benefited structure at the hip. Structure should be considered in fracture prevention research. PURPOSE: Exercise and bisphosphonates reduce fracture risk, but their impact on estimates of bone strength remains uncertain. This study compared changes in tibial bone strength using peripheral quantitative computed tomography (pQCT) and hip structure analysis (HSA) outcomes from dual-energy X-ray absorptiometry (DXA) scans in postmenopausal women with low bone mass assigned to 12 months of exercise, risedronate, or control. METHODS: In this RCT, 276 postmenopausal women within 6 years of menopause were randomly assigned to three groups: exercise (92), risedronate (91), or control (93). Exercise included weighted jogging and progressive resistance exercises; risedronate treatment was 150 mg monthly; all groups received calcium and vitamin D. pQCT and DXA images were obtained at baseline and 6 and 12 months and compared between groups over time. RESULTS: Participants had a mean (± SD) age of 54.5 (± 3.2) years with an average of 36.7 (± 40.7) months postmenopause. No significant differences were found between groups for the change in pQCT outcomes (volumetric bone mineral density, area, and strength estimates). At 12 months, mean percent differences (95% CI) in HSA measures between exercise and controls were as follows: intertrochanteric, cross-sectional area 2.25% (0.28, 4.12) (p = .03), cross-sectional moment of inertia (CSMI) 5.67% (1.47, 9.87) (p < .01), and section modulus (SM) 4.38% (1.02, 7.74) (p = .01), and narrow neck, average cortical thickness 2.37% (-0.08, 4.83) (p = .031). Mean percent differences (95% CI) in HSA measures between risedronate and control were as follows: intertrochanteric, CSMI 4.28% (-0.24, 8.81) (p = .03) and SM 3.35% (-0.21, 6.91) (p = .03), and shaft, subperiosteal width 0.82% (0.05, 1.58) (p = .047), CSMI 2.53% (0.88, 4.18) (p = .004), and SM 1.57% (0.34, 2.8) (p = .008). Exercise maintained neck-shaft angle compared to both control 1.27% (0.13, 2.41) (p = .04) and risedronate 1.31% (0.23, 2.39) (p = .03). All other differences for changes in HSA outcomes over time were not significantly different between the exercise and risedronate groups. CONCLUSION: Exercise and bisphosphonates may influence structural and strength estimates at the hip, but not at peripheral sites (tibia). Neither exercise nor bisphosphonates were found to be superior in improving estimates of hip bone strength.

Blood Variation Implicates Respiratory Limits on Elevational Ranges of Andean Birds.

AbstractThe extent to which species ranges reflect intrinsic physiological tolerances is a major question in evolutionary ecology. To date, consensus has been hindered by the limited tractability of experimental approaches across most of the tree of life. Here, we apply a macrophysiological approach to understand how hematological traits related to oxygen transport shape elevational ranges in a tropical biodiversity hot spot. Along Andean elevational gradients, we measured traits that affect blood oxygen-carrying capacity-total and cellular hemoglobin concentration and hematocrit, the volume percentage of red blood cells-for 2,355 individuals of 136 bird species. We used these data to evaluate the influence of hematological traits on elevational ranges. First, we asked whether the sensitivity of hematological traits to changes in elevation is predictive of elevational range breadth. Second, we asked whether variance in hematological traits changed as a function of distance to the nearest elevational range limit. We found that birds showing greater hematological sensitivity had broader elevational ranges, consistent with the idea that a greater acclimatization capacity facilitates elevational range expansion. We further found reduced variation in hematological traits in birds sampled near their elevational range limits and at high absolute elevations, patterns consistent with intensified natural selection, reduced effective population size, or compensatory changes in other cardiorespiratory traits. Our findings suggest that constraints on hematological sensitivity and local genetic adaptation to oxygen availability promote the evolution of the narrow elevational ranges that underpin tropical montane biodiversity.

Examining effects of habitual physical activity and body composition on bone structure in early post-menopausal women: a pQCT analysis.

After menopause, bones decline in structure and can break more easily. Physical activity can strengthen bones. This study investigated how activity and body composition can impact bone structure in post-menopausal women. Higher levels of physical activity were positively associated with bone structure at the lower leg. PURPOSE: The menopausal transition is characterized by dramatic bone loss, leading to an increased risk of fracture. Few studies have examined how modifiable risk factors influence bone structure. Thus, the objective of this cross-sectional study was to examine the relationship between habitual physical activity (PA), body composition, and bone structure in post-menopausal women with low bone mass. METHODS: Data was analyzed from 276 post-menopausal women with low bone mass enrolled in the Heartland Osteoporosis Prevention Study. Body composition and bone structure measures were collected using dual X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) at the tibia. Habitual PA was collected using the Human Activity Profile questionnaire. Multiple regression analysis was used to determine the relative impact of habitual PA and body composition on bone structure measures (density, area, and strength). Direct and/or indirect effects of PA on bone outcomes were assessed by path analysis. RESULTS: Mean (± SD) age of participants was 54.5 (± 3.2) years and average BMI was 25.7 (± 4.7). Mean T-score of the total lumber spine and hip were - 1.5 (± .6) and - 0.8 (± .59), respectively, with all women classified with low bone mass. Habitual PA had a significant positive effect on bone area and strength measures at the 66% site, and trend effects at the 4% site. Lean mass had a significant positive effect on area and strength at the 66% site and 4% site. Fat mass showed no effect at the 66% site, with a positive effect on density and strength at the 4% site. CONCLUSION: Increased habitual activity was related to improved bone structure of the tibia. Our results in post-menopausal women emphasize that PA and lean mass preservation are important for maintaining bone structure in the years following menopause.

Macrocystis pyrifera source of nutrients for the production of carotenoids by a marine yeast Rhodotorula mucilaginosa.

AIMS: To evaluate an aqueous extract of Macrocystis pyrifera as a nutrient source for the production of carotenoids by a marine Rhodotorula mucilaginosa isolated from seaweed samples. MATERIALS AND RESULTS: The effect of different culture conditions on the concentration of biomass and total pigments was evaluated using a Box-Behnken experimental design. The seaweed extract contained 15% w w-1 of protein and 20% w w-1 of carbohydrate; the main sugar in this fraction was trehalose (78%). The culture conditions that maximize the total pigment concentration (1·84 ± 0·03 mg l-1 ) were initial pH equal to 7, yeast extract as nitrogen source at a concentration of 4 g l-1 , seaweed extract concentration at 25% v v-1 , incubation performed at 25°C and 150 rev min-1 during 6 days. Under optimal growth conditions, three carotenoids were identified among the pigments produced by R. mucilaginosa, lycopene (38·4 ± 9·4%), ß-carotene (21·8 ± 1·5%) and astaxanthin (1·8 ± 0·3%). CONCLUSIONS: Carotenoids of commercial interest (lycopene, ß-carotene and astaxanthin) can be produced using a marine R. mucilaginosa cultivated with an aqueous extract of M. pyrifera as nutrient source. The total pigment concentration in the culture ranged between 0·82 and 1·84 mg l-1 , and was significantly affected by the concentration of the seaweed extract, and yeast extract. SIGNIFICANCE AND IMPACT OF THE STUDY: This work demonstrates that M. pyrifera can be used as a nutrient source for the production of carotenoids by the marine yeast.

Determination of the fundamental absorption and optical bandgap of dielectric thin films from single optical transmittance measurements.

In this work, we propose a method to retrieve the thickness and optical constants of dielectric thin films from single optical transmittance measurements. The method is based on the envelope method and requires a simple dispersion model for the real part of the refractive index with few fitting parameters, while the absorption coefficient can be determined without the aid of a dispersion model. The wavelength-dependent optical constants can be obtained even from spectra that exhibit few interference fringes. We have tested the method with simulated and real transmittance data from thin films in the spectral range covering the fundamental absorption. In order to assess the method's reliability to retrieve the optical constants and optical bandgap, a comparison is performed with the method by Chambouleyron, known as the Pointwise Unconstrained Minimization Approach, and a fit using the Cody-Lorentz dispersion model. We evaluate the methods' capability to retrieve the fundamental absorption and optical bandgap, and their compromise with film thickness accuracy. Finally, the methods are tested and contrasted using optical transmittance of three different semiconductor material thin films.

[Rate of readmissions of patients with heart failure: effects of multifactorial educational interventions]. / Efectividad de las intervenciones educativas con enfoque multifactorial y seguimiento vía telefónica sobre la rehospitalización en pacientes con insuficiencia cardiaca: revisión sistemática y meta-análisis.

We performed a systematic review of the literature to analyze the effect on readmission rates of multifactorial educational interventions at the moment of discharge from the hospital and telephone follow up for patients with heart failure. The quality of reports was analyzed using the CONSORT verification list and the GRADE guide. Using Rev Manager 5.3, the relative risk heterogeneity (RR) of readmission was assessed using I2 and Q statistics, and those considered as homogeneous were combined into a single RR as the confidence interval. We included four reports in the review and three were meta-analyzed. The RR for readmission was 1.01 (95% confidence interval (CI): 0.73-1.40; p = 0.96) with educational interventions and telephone follow-up among patients who visited an emergency room (ER). When studies that included readmission (without ER visit) were combined, the RR was 0.83 (95% CI:0.58-1.17). When studies with visits to ER and readmissions were combined, the RR was 0.91 (95% CI:0.73-1.14). We conclude that educational interventions did not have a significant effect on the rate of readmissions of patients with heart failure.

The 6-hydroxydopamine model and parkinsonian pathophysiology: Novel findings in an older model. / El modelo de 6-hidroxidopamina y la fisiopatología parkinsoniana: nuevos hallazgos en un viejo modelo.

The neurotoxin 6-hydroxydopamine (6-OHDA) is widely used to induce models of Parkinson's disease (PD). We now know that the model induced by 6-OHDA does not include all PD symptoms, although it does reproduce the main cellular processes involved in PD, such as oxidative stress, neurodegeneration, neuroinflammation, and neuronal death by apoptosis. In this review we analyse the factors affecting the vulnerability of dopaminergic neurons as well as the close relationships between neuroinflammation, neurodegeneration, and apoptosis in the 6-OHDA model. Knowledge of the mechanisms involved in neurodegeneration and cell death in this model is the key to identifying potential therapeutic targets for PD.

Transanal Hartmann reversal: a new technique.

BACKGROUND: Hartmann procedure consists in a sigmoidectomy followed by a terminal colostomy. However, the stoma is associated with complications and suboptimal quality of life, so the restoration of colonic continuity should be, at least, considered in any case. Open restoration has been associated with significant morbidity and mortality; therefore, many authors have described the advantages of laparoscopic Hartmann reversal. We want to go a step further showing our experience using a combined laparoscopic and transanal approach in an attempt to improve the surgical technique. METHODS: Patients with an end colostomy due to an emergency Hartmann procedure are selected for this intervention. This approach is performed simultaneously laparoscopically and transanally, with single-port devices, through the colostomy wound in the first case and trough anal canal in the second one. The previous stapler line is resected transanally and the proximal rectum and mesorectum are dissected until the peritoneal reflexion, where both teams work together to complete the adhesiolysis. Finally an end-to-end anastomosis is performed under laparoscopic control. RESULTS: As in patients with rectal cancer, dissection of the stump in Hartmann reversal procedure may be better and associated with shorter operative time. CONCLUSIONS: As with any new surgical procedure, it is probably too early to draw conclusions, but nowadays transanal combined with laparoscopic approach seems to be a safe and feasible technique to perform a Hartmann reversal.

Telocyte Behaviour During Inflammation, Repair and Tumour Stroma Formation.

In this chapter, we outline the role of human CD34+ stromal cells/telocytes (CD34+ SC/TCs) as progenitor cells during repair. The in vivo activation phenomena of CD34+ SC/TCs in this process include increased size; separation from the neighbouring structures (mainly of the vascular walls); association with inflammatory cells, predominantly macrophages; development of the organelles of synthesis (rough endoplasmic reticulum and Golgi apparatus); cell proliferation with presence of mitosis and high proliferative index (transit-amplifying cells); and fibroblastic and myofibroblastic differentiation. A procedure to study these tissue-resident cells, comparison of their behaviour in vivo and in vitro and different behaviour depending on location, time, type of injury (including tumour stroma) and greater or lesser proximity to the injury are also considered.

Bacteria Present in Comadia redtenbacheri Larvae (Lepidoptera: Cossidae).

The external and internal culturable bacterial community present in the larvae of Comadia redtenbacheri Hammerschmidt, an edible insect, was studied. Characterization of the isolates determined the existence of 18 morphotypes and phylogenetic analysis of the 16S rRNA gene revealed the existence of Paenibacillus sp., Bacillus safensis, Pseudomonas sp., Bacillus pseudomycoides, Corynebacterium variabile, Enterococcus sp., Gordonia sp., Acinetobacter calcoaceticus, Arthrobacter sp., Micrococcus sp., and Bacillus cereus. Greater diversity of bacteria was found in those larvae obtained from vendors than in those directly taken from Agave plants in nature. Many of the larvae obtained from vendors presented signs of potential disease, and after the analysis, results showed a greater bacterial community compared with the larvae with a healthy appearance. This indicates that bacterial flora can vary in accordance with how the larvae are handled during extraction, collection, and transport.

"Vascular tuft sign" in neuroendocrine tumors of the pancreas.

The often well-developed microvasculature in pancreatic neuroendocrine tumors (PanNETs) has been studied from different perspectives. However, some detailed structural findings have received less attention. Our objective is to study an overlooked event in PanNETs: "enclosed vascular tufts" (EVTs). For this purpose, 39 cases of PanNETs were examined with conventional (including serial sections) and immunochemistry procedures. In typical EVTs, the results show: 1) an insulated terminal vascular area, with a globular (glomeruloid) aspect, formed by a cluster of coiled microvessels, presenting CD31-, CD34-positive endothelial cells, αSMA-positive pericytes, and perivascular CD34-positive stromal cells/telocytes, separated by a pseudoglandular space from the surrounding trabeculae of tumor neuroendocrine cells; and 2) a pedicle joining the insulated terminal vascular area, with connective tissue tracts around the enclosing tumor trabeculae. EVTs predominate in the trabecular and nested gyriform pattern of PanNETs, with tumor trabeculae that follow a ribbon coil (winding ribbon pattern) around small vessels, which acquire a tufted image. In EVTs, secondary modifications may occur (fibrosis, hyalinization, myxoid changes, and calcification), coinciding or not with those of the connective tracts. In conclusion, the typical characteristics of unnoticed EVTs allow them to be considered as a morphological sign of PanNETs (a vascular tuft sign). Further in-depth studies are required, mainly to assess the molecular pathways that participate in vascular tuft formation and its pathophysiological implications.

Anhedonia in adolescents at transdiagnostic familial risk for severe mental illness: Clustering by symptoms and mechanisms of association with behavior.

BACKGROUND: Anhedonia is a transdiagnostic symptom of severe mental illness (SMI) and emerges during adolescence. Possible subphenotypes and neural mechanisms of anhedonia in adolescents at risk for SMI are understudied. METHODS: Adolescents at familial risk for SMI (N = 81) completed anhedonia (e.g., consummatory, anticipatory, social), demographic, and clinical measures and one year prior, a subsample (N = 46) completed fMRI scanning during a monetary reward task. Profiles were identified using k-means clustering of anhedonia type and differences in demographics, suicidal ideation, impulsivity, and emotional processes were examined. Moderation analyses were conducted to investigate whether levels of brain activation of reward regions moderated the relationships between anhedonia type and behaviors. RESULTS: Two-clusters emerged: a high anhedonia profile (high-anhedonia), characterized by high levels of all types of anhedonia, (N = 32) and a low anhedonia profile (low-anhedonia), characterized by low levels of anhedonia types (N = 49). Adolescents in the high-anhedonia profile reported more suicidal ideation and negative affect, and less positive affect and desire for emotional closeness than low-anhedonia profile. Furthermore, more suicidal ideation, less positive affect, and less desire for emotional closeness differentiated the familial high-risk, high-anhedonia profile adolescents from the familial high-risk, low-anhedonia profile adolescents. Across anhedonia profiles, moderation analyses revealed that adolescents with high dmPFC neural activation in response to reward had positive relationships between social, anticipatory, and consummatory anhedonia and suicidal ideation. LIMITATIONS: Small subsample with fMRI data. CONCLUSION: Profiles of anhedonia emerge transdiagnostically and vary on clinical features. Anhedonia severity and activation in frontostriatal reward areas have value for clinically important outcomes such as suicidal ideation.

Maintenance of permanent sexual activity throughout the year in seasonal bucks using short photoperiodic cycles in open barns.

Seasonality of reproductive activity in rams and bucks is the major constraint in temperate and subtropical zones. Rapid alternation between 1 month of short days and 1 month of long days (LD) over three years in lightproof buildings eliminates this seasonality. We examined if this would also work in open barns, using only supplementary light. Over two years, one group of bucks (n = 7) was subjected to alternate 1 month of LD and 1 month of permanent light (LD-LL) and another group (n = 7) to alternate 1 month of LD and 1 month of natural light (LD-NL). A simultaneous control group, used for both experiments (CG1, n = 6; CG2, n = 6), remained under natural photoperiod. BW, testis weight (TW), plasma testosterone (T) and cortisol (C) were evaluated in all bucks. CG1 and CG2 bucks showed identical dramatic seasonal variations in BW (stable or decreasing in summer), TW (from 85 ± 12 g in February to 127 ± 7 g in July) and T (from 2.7 ± 1.2 ng/mL in January-April to 24.3 ± 3.2 ng/mL in June-October). By contrast, BW of LD-LL and LD-NL bucks increased regularly during the experiment. From 5 and 9 months after the experiment onset, LD-LL and LD-NL bucks, respectively, maintained constant TW of 115 ± 5 g until the experiment end. After the first 3 months <5 ng/mL, T of LD-LL bucks remained constant (5-10 ng/mL) until the experiment end. By contrast, T of LD-NL bucks showed four periods of low (<5 ng/mL) and two periods of high concentrations (18.1 ± 2.6 and 11.9 ± 3.4 ng/mL). Plasma C remained low (5-8 ng/mL) and did not change with group or light treatment. These results show for the first time in any seasonal photoperiodic species that it is possible to maintain the sexual activity of males all year round in open buildings using alternating periods of LD and LL. By contrast, return to NL instead of LL every other month does not prevent seasonality in T concentration. These results raise interesting questions about the photoperiodic control of neuroendocrine regulation of seasonal sexual activity and suggest that these treatments can be used to manage males in open barns in farms and in artificial insemination centres. (Spanish and French versions of the full text are available as Supplementary Materials S1 and S2).

Correction: Emerging pollutants in the Esmeraldas watershed in Ecuador: discharge and attenuation of emerging organic pollutants along the San Pedro-Guayllabamba-Esmeraldas rivers.

Correction for 'Emerging pollutants in the Esmeraldas watershed in Ecuador: discharge and attenuation of emerging organic pollutants along the San Pedro-Guayllabamba-Esmeraldas rivers' by A. Voloshenko-Rossin et al., Environ. Sci.: Processes Impacts, 2015, 17, 41-53, https://doi.org/10.1039/C4EM00394B.

First Report of Meloidogyne marylandi Infecting Bermudagrass in Costa Rica.

Bermudagrass plants (Cynodon dactylon cv. 419) from a soccer field in Santa Ana, San Jose Province, Costa Rica, were found with symptoms of decline with dried leaves and leaf yellowing in patches in February 2012. Roots of the affected plants presented small and smooth galls and protruding egg masses similar to those associated with root-knot nematodes (RKN), Meloidogyne spp. Morphometric and molecular analyses were conducted to identify the species present. Morphological measurements from 30 second-stage juveniles and perineal patterns from 10 adult females matched the description of Meloidogyne marylandi Jepson and Golden. Body length averaged 429.5 ± 18.5 (range: 392 to 459) µm, mean width averaged 16.0 ± 1.3 (range: 13.2 to 18.0) µm, stylet lengths averaged 10.7 ± 1.0 (range: 9.1 to 13.4) µm, dorsal gland orifice from stylet base averaged 2.8 ± 0.3 (range: 2.4 to 3.4) µm, tail lengths averaged 60.9 ± 4.9 (range: 45.5 to 74.7) µm, and the hyaline region of the tails averaged 12.4 ± 1.4 (range: 8.6 to 14.8) µm. Lower average tail length and hyaline tail terminal differentiate M. marylandi from the closely related species M. graminis, the grass root-knot nematode, that can also parasitize bermudagrass (1). Hemizonid position was posterior to the excretory pore. The overall shape of the perineal patterns was ovoid, and the dorsal arch was medium high with lateral lines and coarse striae. Males were rarely observed. DNA was extracted from 10 single mature females. Amplification and sequencing of the mitochondrial DNA region between COII and the lRNA gene was accomplished with primers C2F3 (5'-GGTCAATGTTCAGAAATTTGTGG-3') and 1108 (5'-TACCTTTGACCAATCACGCT-3') (2). A PCR product approximately 520 bp in length was obtained and the sequence (GenBank Accession Nos. KC473862 and KC473863) was compared with those in GenBank using BLAST and showed 99 to 100% identity with known sequences of M. marylandi (JN241916.1, JN241905.1, JN241917.1, JN241921.1, and JN241955.1) (3). Phylogenetic analysis with maximum likelihood (MEGA v.5.0) (4) of those sequences placed the Meloidogyne sp. from Costa Rica in a clade (100% bootstrap support) that included only M. marylandi sequences available from the GenBank database, thus confirming its identity. In addition, digestion of the PCR product with SspI restriction enzyme produced a four band pattern similar to what has been reported for M. marylandi from Israel and United States (Maryland) and this approach is considered useful for the separation of M. marylandi from M. graminis (3). To our knowledge, this is the first report of the root-knot nematode M. marylandi in Costa Rica. References: (1) A. M. Golden. J. Nematol. 21:453, 1989. (2) T. O. Powers and T. S. Harris. J. Nematol. 25:1, 1993. (3) M. A. McClure et al. Plant Dis. 96:635, 2012. (4) K. Tamura et al. Mol Biol Evol. 28:2731, 2011.

Use of transcranial low-intensity focused ultrasound for targeted delivery of stem cell-derived exosomes to the brain.

The blood-brain barrier (BBB) presents a significant challenge for targeted drug delivery. A proposed method to improve drug delivery across the BBB is focused ultrasound (fUS), which delivers ultrasound waves to a targeted location in the brain and is hypothesized to open the BBB. Furthermore, stem cell-derived exosomes have been suggested as a possible anti-inflammatory molecule that may have neural benefits, if able to pass the BBB. In the present study, transcranial low-intensity focused ultrasound (LIFU), without the use of intravenous microbubbles, was assessed for both (1) its ability to influence the BBB, as well as (2) its ability to increase the localization of intravenously administered small molecules to a specific region in the brain. In vivo rat studies were conducted with a rodent-customized 2 MHz LIFU probe (peak pressure = 1.5 MPa), and injection of labeled stem cell-derived exosomes. The results suggested that LIFU (without microbubbles) did not appear to open the BBB after exposure times of 20, 40, or 60 min; instead, there appeared to be an increase in transcytosis of the dextran tracer. Furthermore, the imaging results of the exosome study showed an increase in exosome localization in the right hippocampus following 60 min of targeted LIFU.

Ultrastructure of myopericytoma: a continuum of transitional phenotypes of myopericytes.

The authors report the ultrastructural characteristics of myopericytoma, a recently described variant of perivascular (pericytic) tumors, mainly with regard to their myopericytic cells and vessels. Myopericytes range between pericytes and vascular smooth muscle cells (SMCs) in a morphologic continuum. The principal findings of the intermediate phenotypes are (1) elongated or annular morphology with processes of varying length and thickness (usually long and thin); (2) a continuous, irregularly thickened and zonally duplicated basement membrane; (3) heterocellular "peg and socket" junctions with neighboring endothelial cells, and scarce specialized junctions between myopericytes; (4) numerous micropinocytotic vesicles, whether continuous or forming focal rows; (5) abundant thin microfilaments, grouped in bundles with dense bodies and adhesion plaques; (6) poorly developed synthetic system (RER and Golgi); (7) pseudointracellular bodies formed by invagination of basement and plasma membranes, with numerous endocytic vesicles; and (8) zones of cytoplasmic rarefaction near micropinocytotic vesicles and intracellular organelles. The ultrastructure of myopericytes therefore makes it possible to distinguish them from pericytes, SMCs, and fibroblast/myofibroblasts, which is useful for myopericytoma diagnosis. The main pattern of the vessels, with perivascular concentric and multilayered growth of myopericytes (a thick wall in contrast to a small lumen) and lack of elastic material, also supports an intermediate form between pericytic and muscular microvasculature. The presence of myopericytes more similar to SMCs and of hemangiopericytoma-like vessels concurs with transitional forms with angioleyomyoma and true hemangiopericytoma, histogenetically representing a morphologic continuum for the perivascular tumors.

Sexually active male goats stimulate the endocrine and sexual activities of other males in seasonal sexual rest through the "buck-to-buck effect".

Male goats rendered sexually active by exposure to a photoperiodic treatment are more efficient than untreated goats in stimulating LH secretion and ovulation in seasonally anestrous goats. This phenomenon is called the "male effect." Here, we determined whether sexually active bucks are able to stimulate the endocrine and sexual activities of other bucks in seasonal sexual rest through the phenomenon that we called the "buck-to-buck effect." We used bucks rendered sexually active (SA) during sexual rest by exposure to 2.5 mo of artificial long days (16 h of light per d) and untreated, sexually inactive (SI) bucks. In Experiment 1, we determined the short-term (21 d) LH and testosterone responses of sexually inactive bucks joined with a SA or SI buck. In Experiment 2, we determined the long-term (60 d) testosterone and sexual behavior responses of sexually inactive bucks joined with 2 SA or SI bucks. In Experiment 3, we determined the efficacy of bucks initially exposed to the buck-to-buck effect, the SABB bucks, to thereafter induce a "classical" male effect in seasonally anestrous goats. In Experiments 1 and 2, there was an interaction between time and groups in LH and testosterone plasma concentrations (P < 0.01). In Experiment 1, plasma LH concentrations were greater in bucks joined with a SA buck than in those joined with an SI buck (P < 0.05). In Experiments 1 and 2, testosterone concentrations were greater in bucks joined with SA bucks than in those joined with SI bucks (P < 0.05). In addition, in Experiment 2, the sexually inactive bucks joined with SA bucks displayed more nudging than those joined with SI bucks (P < 0.001). In Experiment 3, kidding rates did not differ between females joined with SA (34 of 40: 85%) or SABB bucks (32 of 40: 80%; P > 0.05). We concluded that the endocrine and sexual activities of bucks during sexual rest can be stimulated by SA bucks. In addition, SABB bucks are able to stimulate the reproductive activity of seasonally anestrous goats.