Rearing mice from birth in an enriched environment leads to a conspicuous acceleration of visual system development appreciable at behavioral, electrophysiological and molecular level. Little is known about the possible mechanisms of action through which enriched environment affects visual system development. It has been suggested that differences in maternal behavior between enriched and non-enriched conditions could contribute to the earliest effects of enriched environment on visual development and that neurotrophins, BDNF in particular, might be involved. Here, we examined Brain Derived Neurotrophic Factor (BDNF) levels in the visual cortex during development and showed that an increase occurs in the first week of life in enriched pups compared to standard reared pups; BDNF levels at birth were equal in the two groups. This suggests a postnatal rather than a prenatal effect of environment on BDNF. A detailed analysis of maternal care behavior showed that pups raised in a condition of social and physical enrichment experienced higher levels of licking behavior and physical contact compared to standard reared pups and that enhanced levels of licking were also provided to pups in an enriched environment where no adult females other than the mother were present. Thus, different levels of maternal care in different environmental conditions could act as indirect mediator for the earliest effects of enrichment on visual system development. Some of the effects of different levels of maternal care on the offspring behavior are long lasting. We measured the visual acuity of differentially reared mice at the end of the period of visual acuity development (postnatal day 45) and at 12 months of age, using a behavioral discrimination task. We found better learning abilities and higher visual acuity in enriched compared to standard reared mice at both ages. 相似文献
OBJECTIVES: Chromosomal rearrangements can lead to infertility or repeated spontaneous or induced abortions. The use of preimplantation genetic diagnosis (PGD) allows the selected transfer of chromosomally balanced embryos. The aim of this study was to carry out detailed analysis of the outcome of 11 PGD cycles for 8 patients carrying various chromosomal rearrangements. METHODS: Patients underwent routine in vitro fertilisation with biopsy of embryos on day 3. Specific fluorescent in situ hybridisation protocols were developed for each couple. Embryo transfer was possible in all 11 cycles. RESULTS: The outcome was four pregnancies, leading to three live births and one biochemical pregnancy. Post-zygotic mosaicism was detected in 75% of untransferred embryos, the majority of which were chaotic. Detailed follow-up and analysis provided evidence for the co-existence of chromosomally balanced and abnormal cells in six embryos. The mechanisms involved included chromosome breakage and loss of material. CONCLUSIONS: Biopsy and analysis of two blastomeres, where possible, reduced the risk of misdiagnosis in cases of balanced/aneuploid mosaics. The three live births achieved for the eight couples treated in this series, despite the poor history in almost all cases, is further proof that a policy of biopsying two cells from embryos consisting of six or more cells and a single cell from four- or five-cell embryos is compatible with a positive outcome. 相似文献
Substantial experimental data suggest that tumour progression is associated with angiogenesis and that increase in microvessel density (MVD) is associated with increase in mast cells density (MCD). Dog mast cell tumour (MCT) is common in dog with an incidence much higher than that found in human and in both species several common biological and clinical characteristics have been demonstrated. To evaluate the role of angiogenesis in progression of this tumour and to correlate MVD and MCD, in this study a series of 78 MCT was investigated. Serial sections obtained from biopsy specimens were processed with toluidine blue staining, specific for MC identification, and by immunohistochemistry using a polyclonal antibody anti factor VIII-related antigen (FVIII-RA), used as an endothelial marker, and MVD and MCD were determined. Results showed that MVD was significantly higher in poorly differentiated (G3) MCTs than in intermediate (G2) and well differentiated (G1) MCTs and that MCD and MVD were significantly correlated in G3, but not in G1 and G2 subgroups. These data indicate that angiogenesis and MCD are significantly correlated in MCTs progression. 相似文献
BACKGROUND: Recent studies have suggested that electroencephalogram bispectral index (BIS) monitoring can improve recovery after anaesthesia and save money by shortening patients postoperative stay. The aim of the study is to evaluate the management of drugs and to measure immediate recovery after anaesthesia with or without BIS monitoring. METHODS: We studied 90 patients undergoing abdominal surgery randomly allocated to one of two groups of 45 each with or without BIS monitoring. Standard monitoring (EKG, arterial oxygen saturation and non-invasive blood pressure) was applied. All groups were monitored with BIS, using electrodes (Zipprep, Aspect Medical Systems) applied to the forehead. In the group 2 the BIS value was blinded to the anaesthesiologist. The BIS value was displayed using Spacelabs Medical BIS Ultraview Monitor. After obtaining baseline values for the BIS index (group 1) and haemodynamic data (all groups) anaesthesia was induced with a bolus dose of remifentanil and TPS, and vecuronium. The anaesthesia was maintained with Remifentanil and Sevoflurane. At standard times BIS, haemodynamic and respiratory parameters were recorded. Recovery times were measured by a study coordinator. Drug consumption was calculated. RESULTS: In group 1 the consumption of Sevoflurane decreased by 40 % while the consumption of remifentanil decreased by 10 % as compared to group 2. The use of vecuronium did not change in the 2 groups. In group 1 the time elapsed from cessation of anaesthetics to orientation decreased significantly. The difference was 5 min, from 11 to 6 min. CONCLUSIONS: BIS monitoring decrease both sevoflurane and remifentanil consumption, when compared to anaesthesia without BIS, with an immediate recovery after sevoflurane and remifentanil anaesthesia. 相似文献
Background: Obesity causes anesthesiologists a broad variety of perioperative theoretical and practical problems. The aim
of this study was to compare two protocols of anesthesia employing Isoflurane and Sevoflurane and evaluate the cardiorespiratory
parameters, postoperative recovery and analgesia. Methods: 90 patients underwent biliopancreatic diversion. 60 patients (group
A) received Isoflurane and 30 patients (group B) were anesthetized with Sevoflurane. Intraoperative monitoring consisted of
EKG, invasive arterial pressure, Sp02, EtCO2, Etanest, Spirometry, urinary output and TOF. Cardiorespiratory parameters and end tidal expiratory concentrations of volatile agents
were collected during specific phases of surgery: 1) before induction of anesthesia, 2) after intubation, 3) after skin incision,
4) after positioning of costal retractors, 5) in the reverse Trendelenburg position, 6) end of surgery. During the postoperative
period the Aldrete test was carried out to evaluate the recovery from anesthesia. VAS was administered for 6 hours after the
end of surgery to set the quality of analgesia. Results: No statistically significant differences in cardiorespiratory parameters
were found between the two groups. Extubation time was significantly less in the Sevoflurane Group than in the Isoflurane
(15 ± 7 min vs 24 ± 5 min, p< 0.05). The Sevoflurane Group showed an Aldrete score significantly higher than the Isoflurane
(8.8 ± 0.3 vs 8.1 ± 0.4, p < 0.05). VAS values did not show statistical differences. Conclusion: The introduction of Sevoflurane,
a volatile agent with rapid pharmacokinetic properties, seems to offer an interesting application in these patients. 相似文献
OBJECTIVE: We tested the hypothesis that subjects randomized to the 6 mL/kg predicted body weight tidal volume study group of the National Institutes of Health Acute Respiratory Distress Syndrome (ARDS) Network study had higher levels of intrinsic positive end-expiratory pressure (PEEP) than subjects randomized to the 12 mL/kg predicted body weight tidal volume study group. DESIGN: Secondary analysis of a subgroup from a randomized controlled trial. SETTING: Hospitals located in San Francisco, CA, and Seattle, WA. PATIENTS: Eighty-four patients enrolled in the ARDS Network tidal volume trial in San Francisco, CA, and Seattle, WA, with records of measurement of intrinsic PEEP. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Intrinsic PEEP was assessed a median of six times over the first 48 hrs of ARDS Network protocol ventilation in study subjects, with no significant difference in number of measurements between subjects randomized to the tidal volume protocol of 6 mL/kg compared with 12 mL/kg. We found that intrinsic PEEP was higher among subjects randomized to the 6 mL/kg protocol, with a median intrinsic PEEP of 1.3 cm H2O (interquartile range, 0-3.1 cm H2O), compared with a median intrinsic PEEP of 0.5 cm H2O (interquartile range, 0-1.5 cm H2O) among subjects randomized to 12 mL/kg (p = .029). There was no difference in total PEEP between the study groups. CONCLUSIONS: In a subgroup of ARDS Network subjects, intrinsic PEEP was statistically significantly higher in subjects randomized to the 6 mL/kg protocol than those in the 12 mL/kg study group. The amount of intrinsic PEEP was very low in both study groups, and difference of median intrinsic PEEP between the groups was <1 cm H2O. It is unlikely that the difference in intrinsic PEEP between the study groups was clinically important in the ARDS Network study of low tidal volume ventilation. 相似文献
No studies analyzing the role of dementia as a risk factor for mortality in patients affected by COVID-19. We assessed the prevalence, clinical presentation and outcomes of dementia among subjects hospitalized for COVID19 infection.
Design
Retrospective study.
Setting
COVID wards in Acute Hospital in Brescia province, Northern Italy.
Participants
We used data from 627 subjects admitted to Acute Medical wards with COVID 19 pneumonia.
Measurements
Clinical records of each patients admitted to the hospital with a diagnosis of COVID19 infection were retrospectively analyzed. Diagnosis of dementia, modalities of onset of the COVID-19 infection, symptoms of presentation at the hospital and outcomes were recorded.
Results
Dementia was diagnosed in 82 patients (13.1%). The mortality rate was 62.2% (51/82) among patients affected by dementia compared to 26.2% (143/545) in subjects without dementia (p<0.001, Chi-Squared test). In a logistic regression model age, and the diagnosis of dementia resulted independently associated with a higher mortality, and patients diagnosed with dementia presented an OR of 1.84 (95% CI: 1.09–3.13, p<0.05). Among patients diagnosed with dementia the most frequent symptoms of onset were delirium, especially in the hypoactive form, and worsening of the functional status.
Conclusion
The diagnosis of dementia, especially in the most advanced stages, represents an important risk factor for mortality in COVID-19 patients. The clinical presentation of COVID-19 in subjects with dementia is atypical, reducing early recognition of symptoms and hospitalization.
In Uganda, public human immunodeficiency virus (HIV) Voluntary Counseling and Testing (VCT) services are mainly provided through
the facility based model, although the home based approach is being promoted as a strategy for improving access to VCT. However
the uptake of VCT varies according to service delivery model and is influenced by a number of factors. The aim of this study
therefore, was to compare predictors for uptake of facility and home based VCT in a rural context. 相似文献