Ovarian senescence in the rhesus monkey (Macaca mulatta)

BACKGROUND: A decline in fertility is evident in human females past their middle thirties. This 'reproductive senescence', marked by a sharp decline in pregnancy rates, may be attributed to reductions in numbers of available oocytes and their quality. Because Old World primates exhibit ovarian morphology and physiological control and timing of menstrual cycles closely resembling those of humans, the current study investigated the rhesus macaque as a potential model for human reproductive senescence. METHODS: Ovaries collected from females aged 1-25 years and divided into five age groups were analysed histologically. RESULTS: General ovarian morphology demonstrated significant changes as the females approached menopause. The proportions of primordial and primary follicles all demonstrated significant differences across age groups (primordial: 77.1, 79.9, 69.7, 62.9, 55.1%; primary: 21.5, 18.8, 28.5, 35.2, 43.1% for age groups 1 to 5 respectively; P<0.0001 for both). Samples from females approaching or undergoing the menopausal transition (aged 20-25 years) demonstrated evidence of ovarian senescence, having scattered and atretic follicles, low numbers of primordial follicles and reduced stromal tissue. CONCLUSION: This study supports the value of the rhesus monkey as a model for reproductive ageing because its ovary undergoes follicular reservoir depletion similar to that seen in humans.     

Deprivation of sensory inputs to the olfactory bulb up-regulates cell death and proliferation in the subventricular zone of adult mice

The main olfactory bulb (MOB) is the first relay on the olfactory sensory pathway and the target of the neural progenitor cells generated in the subventricular zone (SVZ) lining the lateral ventricles and which migrate along the rostral extension of the SVZ, also called the rostral migratory stream (RMS). Within the MOB, the neuroblasts differentiate into granular and periglomerular interneurons. A reduction in the number of granule cells during sensory deprivation suggests that neurogenesis may be influenced by afferent activity. Here, we show that unilateral sensory deafferentation of the MOB by axotomy of the olfactory receptor neurons increases apoptotic cell death in the SVZ and along the rostro-caudal extent of the RMS. The vast majority of dying cells in the RMS are migrating neuroblasts as indicated by double Terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick-end labeling/PSA-NCAM labeling. Counting bromodeoxyuridine-labeled cells in animals killed immediately or 4 days after tracer administration showed a bilateral increase in proliferation in the SVZ and RMS which was balanced by cell death on the operated side. These data suggest that olfactory inputs are required for the survival of newborn neural progenitors. The greatest enhancement in proliferation occurred in the extension of the RMS located in the MOB, revealing a population of local precursors mitotically stimulated following axotomy. Together, these findings indicate that olfactory inputs may strongly modulate the balance between neurogenesis and apoptosis in the SVZ and RMS and provide a model for further investigation of the underlying molecular mechanisms of this activity-dependent neuronal plasticity.     

Central hemodynamic changes in experimental muscle crush injury in pigs

To investigate central and pulmonary hemodynamics in a standardized normovolemic experimental muscle injury model, 8 anesthetized and mechanically ventilated test pigs were intracavally infused with 100 ml of autologous muscle extract over a period of 100 min; 8 control pigs received Ringer's solution. The cardiac index decreased 20% and the heart rate decreased 10% within 30 min of starting the infusion in the muscle extract group and remained depressed. Mean arterial pressure increased significantly in both groups. The pulmonary capillary wedge pressure and central venous pressure remained relatively unchanged during the 5-hour study. A 2-fold increase in mean pulmonary arterial pressure and a nearly 4-fold increase in the pulmonary vascular resistance index was seen in the muscle extract infusion group, which however returned to normal. Arterial hemoglobin concentration and systemic vascular resistance index remained fairly stationary in both groups. Immediate significant decreases in both arterial oxygen saturation and arterial oxygen tension were observed in the muscle extract group, however both variables recovered towards the end of the experiment. A slight increase in arterial blood pH value was noted during the experiment. In conclusion, autologous muscle extract infusion causes decreases in heart rate and cardiac index, as well as a significant increase in pulmonary vascular tone and systemic hypoxemia, emphasizing the detrimental effects of skeletal muscle injury following severe trauma.     

Visual distortions and dissociation

Visual distortions may be a frightening experience. They are often incorrectly diagnosed and easily dismissed. The causes of visual distortions are poorly understood. The aim of this study was to investigate the link between visual distortions and dissociative experiences in a nonclinical population. A total of 297 nonclinical volunteers completed the Dissociative Experience Scale and answered questions concerning visual distortions. Our study suggests that visual distortions are quite common and that there is a clear link between visual distortions and dissociative phenomena. Literature indicates that this may be caused by disturbances in brain lateralization. Bilateral language capacity may interfere with abilities usually associated with the nondominant hemisphere. Research efforts attempting to shed light on the above matter may benefit our knowledge for dissociative phenomena. An interdisciplinary approach is needed.     

Measles history and atopic diseases: a population-based cross-sectional study

Context  Many recent cross-sectional studies have suggested that lack of early exposure to communicable diseases, including measles, in affluent countries may have increased rates of atopic disease. Objective  To study the association between natural measles infection and atopy. Design and Setting  Cross-sectional nationwide study in Finland using data gathered between November 1, 1982, and June 30, 1986. Subjects  A total of 547,910 individuals aged 14 months to 19 years who at the time of measles-mumps-rubella (MMR) vaccination had relevant information collected on the occurrence of measles and allergic rhinitis, eczema, and asthma. Main Outcome Measures  Lifetime occurrence of atopic manifestations in subjects who had had measles compared with those who had not, expressed as age-specific and age-adjusted prevalence ratios. Results  The age-adjusted prevalence ratio of atopic manifestations among those who had had measles (n = 20,690) compared with those who had not (n = 527,220) was 1.32 (95% confidence interval [CI], 1.27-1.36) for eczema, 1.41 (95% CI, 1.33-1.49) for rhinitis, and 1.67 (95% CI, 1.54-1.79) for asthma. The positive association between measles and atopy was evident at all ages, in both urban and rural dwellers, and among subjects with many or few contacts at home or in day care. Conclusions  Based on our data, measles and atopy occur more frequently together than expected, which does not support the hypothesis that experiencing natural measles infection offers protection against atopic disease.      

Efficacy of salbutamol via Easyhaler unaffected by low inspiratory flow

The fine particle dose delivered via dry powder inhalers (DPIs) is often affected by the inspiratory flow rate generated during inhalation. This has clinical implications, since the fine particle dose determines the amount of drug reaching the lungs. With Easyhaler DPI the fine particle dose remains relatively constant over the range of inspiratory flow rates from 30-60 l min(-1). The aim of this study was to confirm that clinical efficacy is maintained even at low flow rates by comparing the bronchodilating effect of salbutamol (100 microg) delivered via Easyhaler at a target inspiratory flow of 30 l min(-1) with the same dose of salbutamol via pressurised metered-dose inhaler (pMDI) plus spacer. This was a double-blind, randomized, cross-over study with double-dummy technique. Twenty-one paediatric and adult asthmatic patients completed the study, which was conducted over 2 study days. The main outcome parameter was forced expiratory volume in 1 sec (FEV1). The patients were trained to generate a low peak inspiratory flow rate (PIFR) of 30 l min(-1), and the actual PIFR through Easyhaler was recorded. The average PIFR through Easyhaler was 28.7 l min(-1). The difference in the maximum value of FEV1 (FEV1max) between the treatments after drug inhalation was 0.01 l. The mean of FEV1max was 2.67 l after pMDI plus spacer compared to 2.69 l after Easyhaler. Improvements in FEV1 were clinically significant. No significant differences between treatments were found. A reasonably low inspiratory flow rate through Easyhaler produces an equivalent improvement in lung function to a correctly used pMDI plus spacer. Hence, Easyhaler can be used with confidence in patients who may have difficulty in generating a high inspiratory flow rate, such as children and the elderly.     

Persistence of measles, mumps, and rubella antibodies in an MMR-vaccinated cohort: a 20-year follow-up

BACKGROUND: The persistence of antibodies against measles, mumps, and rubella induced by the measles-mumps-rubella (MMR) vaccine and the kinetics of antibody decline after the second MMR vaccine dose were studied in the same cohort for 20 years. METHODS: Measles, mumps, and rubella antibodies were measured by enzyme immunoassay in 20-year follow-up serum samples (n= 183) of twice-vaccinated individuals, and measles antibodies were also measured in oral fluids (n = 177). Antibody decay was determined in a group (n = 58) with subsequent samples collected 1, 8, and 15 years after the second MMR dose. RESULTS: In total, 95%, 74%, and 100% of 183 vaccinees were still seropositive for measles, mumps, and rubella, respectively, and 85% of 177 vaccinees had measurable measles antibodies in their oral fluids. The antibody levels declined significantly after the second dose, but subsequently the rate of decline was slower. CONCLUSIONS: A high rate of seropositivity was found 20 years after the first MMR dose, particularly for rubella and measles. Our results show that MMR vaccine-induced antibodies wane significantly after the second dose. According to epidemiological data, the protection induced by MMR vaccination in Finland seems to persist at least until early adulthood. However, the situation requires constant vigilance.     

Drainage of the inferior vena cava to the left atrium

Drainage of the inferior vena cava to the left atrium is an extremely unusual congenital heart disease. We describe a 54-year-old woman, in whom the diagnosis was suggested by transthoracic echocardiography, and then confirmed by a transesophageal exam and magnetic resonance imaging, which also revealed an associated secundum atrial septal defect. Surgical management involved reconstruction of the interatrial septum to include the inferior vena cava in the right atrium. The few previously reported cases in the literature are reviewed.     

Encephalitozoon cuniculi strain III is a cause of encephalitozoonosis in both humans and dogs

Microsporidia are obligate intracellular eukaryotic organisms found in a wide range of vertebrate and invertebrate hosts. Encephalitozoon cuniculi is commonly found in domestic rabbits and rodents and also occurs in dogs, other canids, and primates, including humans. DNA sequencing of the ribosomal RNA genes has been used to identify these parasites to a species level and to define E. cuniculi strains I, II, and III. Eight new dog isolates were characterized as E. cuniculi strain III by use of molecular methods. This strain has also been identified in isolates from immunocompromised humans, suggesting the zoonotic potential of this parasite species. Prolonged microsporidial spore shedding from asymptomatic dogs is also reported.     

Shortened hospital stay for childhood bone and joint infections: Analysis of 265 prospectively collected culture-positive cases in 1983-2005

Abstract Background: In recent decades the treatment of childhood acute bone and joint infections has shifted towards shorter antibiotic courses and rapid transition to oral therapy. Methods: We prospectively collected 265 culture-positive cases of non-neonatal bone and joint infections in Finnish children during 1983-2005. The duration of antimicrobial treatment and the extent of surgery were defined in the study protocol, but for ethical reasons, the liaison clinician determined the time of discharge using normalization of the serum C-reactive protein (CRP) level as a yardstick. We examined changes during the study in the distribution of causative organisms, severity of disease, and length of hospital stay. Results: Staphylococcus aureus was overwhelmingly the most common causative agent throughout the study, whereas Haemophilus influenzae type b was eliminated soon after the introduction of vaccination. The mean time from initial symptoms to presentation remained the same at 4 days, and no significant change was observed in the severity of disease, CRP, or the rate of sequelae. The mean duration of intravenous antibiotic administration was only 4 days. The average hospital stay shortened significantly from 13 days to 9 days (p =?0.0001). Conclusions: The shortened hospital stay was not due to a change in the anatomical site of these infections, but to simplified treatment. Considerable savings in hospital stay, and thus costs, are feasible in osteoarticular infections of childhood by using CRP in monitoring the disease and shortening intravenous treatment by a swift move to per oral administration.