Caffeine reverses age-related deficits in olfactory discrimination and social recognition memory in rats. Involvement of adenosine A1 and A2A receptors

Caffeine, a non-selective adenosine receptor antagonist, has been suggested as a potential drug to counteract age-related cognitive decline since critical changes in adenosinergic neurotransmission occur with aging. In the present study, olfactory discrimination and short-term social memory of 3, 6, 12 and 18 month-old rats were assessed with the olfactory discrimination and social recognition tasks, respectively. The actions of caffeine (3.0, 10.0 and 30.0 mg/kg, i.p.), the A1 receptor antagonist DPCPX (1.0 and 3.0 mg/kg, i.p.) and the A2A receptor antagonist ZM241385 (0.5 and 1.0 mg/kg, i.p.) in relation to age-related effects on olfactory functions were also studied. The 12 and 18 month-old rats exhibited significantly impaired performance in both models, demonstrating deficits in their odor discrimination and in their ability to recognize a juvenile rat after a short period of time. Acute treatment with caffeine or ZM241385, but not with DPCPX, reversed these age-related olfactory deficits. The present results suggest the participation of adenosine receptors in the control of olfactory functions and confirm the potential of caffeine for the treatment of aged-related cognitive decline.     

Group‐specific component (GC) in curiaú and pacoval,two african‐derived brazilian populations

The group‐specific component (GC) system is of interest in anthropological genetic studies because the distribution of its subtypes distinguishes among major ethnic groups. The GC system was analyzed in Curiaú and Pacoval, two remnant Quilombo populations (African‐derived populations) from the Brazilian Amazon. There was no significant statistical difference in allelic frequencies between the two populations or between them and three other African‐derived Brazilian populations (Mimbó, Sítio Velho, and Gaucinha in Northeastern Brazil). These populations share similarities among themselves and with African populations (high frequencies of GC*1F and lower frequencies of GC*1S), which may reflect the influence of a high level of African contribution to their formation, but there is a clear difference between them and Europeans and South American Indians. It is suggested that the GC system is a useful marker for studying relationships between single populations and major ethnic groups, but does not discriminate between populations which share the same parental stock. Am. J. Hum. Biol. 13:718–720, 2001. © 2001 Wiley‐Liss, Inc.     

How a community-based organization and an academic health center are creating an effective partnership for training and service.

Community-academic partnerships in the training of doctors offer unique learning opportunities of great importance. Such partnerships can induce a paradigm shift such that physicians view community as a teaching resource and partner rather than as a passive recipient of services or solely as a placement site. The authors describe a model of a community-academic partnership in New York City, begun in 1995, in which, for training and service, pediatric residents are integrally involved in a community-based program. Principles adapted from the Community-Campus Partnerships for Health's principles of partnership provide a framework for portraying the essential elements of developing and maintaining the partnership. The authors explain the clashes that may arise between partners and show how the principles of partnership guide partnership members in working and learning within a setting that by its nature entails conflict and inequality. This report is based on the knowledge gained from the structured reflections of both members of this partnership: the residency program at a large academic health center and the community-based social service organization. Such partnerships provide the training ground for the development of physicians who understand the social and cultural determinants of health and constructively use community agencies' input in promoting child health and well-being. Within this framework, community-based organizations are not solely service providers but become educators of physicians-in-training who, with new knowledge gained through the partnership, more effectively contribute to the overall health of the communities they serve.     

Immunohistochemical study on the development of the adenohypophysial cells in the lizard Gallotia galloti

Summary Immunohistochemical methods have been used to study the embryonic and postnatal development of the hormone-producing cells in the adenohypophysis of the lizard Gallotia galloti. In this species, Rathke's pouch is formed between stages 30 to 32 of the embryonic development, although the first sign of immunoreactivity to antisera against adenohypophysial hormones occurs in stage 33 in the pars distalis anlage. These cells derive from the dorsal face of Rathke's pouch and are immunoreactive to anti-ACTH serum. The cytodifferentiation of ACTH and MSH cells occurs in the pars intermedia in stage 34. The TSH cells appear at stage 35 and the gonadotrope cells at stage 37. These cells derive from both the dorsal and ventral face of the Rathke's pouch. The LTH cells are revealed at stage 39 and are only originated from the dorsal face. The STH cells, which come from the dorsal as well as ventral face, are the last secretory cells differentiated just before hatching. During postnatal development an increase and also a redistribution of the immunoreactive cells occur until acquiring the adult distribution.     

Lycium barbarum polysaccharide fraction associated with photobiomodulation protects from epithelium thickness and collagen fragmentation in a model of cutaneous photodamage

Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The...     

Donor Choriocarcinoma Transmission From Solid Organ Transplantation: A Case Report

Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.     

Baccharis trimera: effect on hematological and biochemical parameters and hepatorenal evaluation in pregnant rats

AIM OF THE STUDY: This investigation evaluated the effect of a hydroethanolic extract of Baccharis trimera on pregnant Wistar rats, once the plant is well-known consumed in pregnancy and little is known on its potentially toxic effects on pregnant women. MATERIAL AND METHODS: Thirty-five female rats were distributed into three groups. Those in treatments 1 and 2 were given 8.4 mg/kg of the extract orally from gestational day (GD) 1 to 19 and from GD 6 to 15, respectively, whereas those in the control group received distilled water orally from GD 1 to 19. Body weights were recorded on GD 1, 6, 15, and 20. On GD 20 animals were anesthetized, blood samples were collected and maternal livers, kidneys, and spleens were weighed and processed for histological studies. RESULTS: No clinical signs of maternal toxicity and no changes in hematological parameters were observed. Urea levels and kidney weights differed significantly between animals receiving treatment 1 and controls. Histopathological alterations were found in kidneys and livers in both treatment groups. CONCLUSIONS: The hydroethanolic extract of Baccharis trimera administered to pregnant rats at 8.4 mg/kg was toxic to maternal kidney and liver cells, although such alterations are reversible once administration is discontinued.     

Heart rate variability,exercise capacity and levels of daily physical activity in children and adolescents with mild-to-moderate cystic fibrosis

Background:Autonomic nervous system balance is altered in cystic fibrosis (CF), although its influence on physical fitness has been poorly explored.Objective:This study aimed to evaluate the association of heart rate variability (HRV) with exercise capacity and levels of daily physical activity in children and adolescents with mild-to-moderate CF.Methods:A cross-sectional study including individuals with CF aged 6–18 years, not under CFTR modulator therapy, was performed. Sociodemographic (age, sex) and clinical information (airway colonization, pancreatic insufficiency, and genotyping) were collected. In addition, exercise capacity (modified shuttle test — MST), lung function (spirometry), body composition (bioimpedance), levels of daily physical activity (5-day accelerometer), and HRV (both at rest and during the MST) were evaluated.Results:30 individuals (20 females) aged 11.2±3.7 years, mean FEV162.8±27.6%, were included. A sympathovagal balance (LF/HF) increase (p<0.001) during the MST was shown, indicating a predominance of sympathetic modulation. The standard deviation of all RR intervals (SDNN) and the high frequency (HF) index during exercise correlated significantly with FEV₁ (r=0.45, p=0.01 and r=0.46, p=0.01; respectively). MST distance also correlated positively and significantly with SDNN (r=0.43, p=0.01), square root of the mean of the sums of squares of frequencies between RR intervals greater than 50 ms — RMSSD (r=0.53, p<0.01), low frequency — LF (r=0.48, p<0.01), HF (r=0.64, p<0.01), dispersion of points perpendicular to the short-term identity line — SD1 (r=0.40, p=0.02) and negatively with LF/HF (r=−0.57, p<0.01). Regarding daily physical activity, SDNN at rest (r=0.37, p=0.04) and exercise (r=0.41, p=0.02) showed positive correlations with time in moderate-to-vigorous activities. When normalizing the SDNN and classifying individuals as normal or altered, those presenting altered SDNN showed poorest FEV₁ (p=0.001) and lower exercise capacity (p=0.027).Conclusion:HRV correlates with lung function, exercise capacity and levels of daily physical activity in children and adolescents with CF. The study highlights the influence of CF on autonomic function and suggests HRV measurement as an easy tool to be used in clinical settings as an alternative marker to monitor CF individuals.