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991.
The movement patterns of three commercially important wrasse (Labridae) species inside a small marine protected area (~ 0.15 km2) on the west coast of Norway were analysed over a period of 21 months. The mean distance between capture and recapture locations varied between 10 and 187 m, and was species and season specific. The extent of movement was not related to body size or sex. These results imply that a network of small strategically located marine protected areas can be used as management tools to protect wrasses from size- and sex-selective fishing mortality.  相似文献   
992.
Probiotics and Antimicrobial Proteins - Bacterial spores of the genus Bacillus are being evaluated as adjuvant molecules capable of improving the immune response to vaccines. In this study, we...  相似文献   
993.
994.
Fish of the genus Selene, known as lookdowns or moonfish, are one of the most morphologically derived groups of the family Carangidae, whose phylogenetic relationships are still largely unknown. In this study, we discuss karyoevolutionary aspects of three representatives of this genus from the Western Atlantic: Selene brownii (2n = 48; FN = 48), Selene setapinnis (2n = 46; FN = 48), and Selene vomer (2n = 48; FN = 50). Their body patterns were also investigated and compared to one another and in relation to two other species of different genera. Two mechanisms of karyotypic evolution seem to have acted in the diversification of this genus, namely pericentric inversions and centric fusions. Mapping of rDNA sequences showed that chromosome pairs bearing 5S rDNA sites are similar, whereas those bearing 18 rDNA sites are morphologically distinct while apparently also exhibiting interspecies synteny. Although the nucleolar organizer-bearing chromosomes are extremely efficient cytotaxonomic markers among Selene species, others cytogenetic patterns of these species are relatively conserved. Hybridization with telomeric probes (TTAGGG)n did not exhibit interstitial telomeric sites (ITS), especially in S. setapinnis, where, along with a reduction in diploid number, a large metacentric pair derived from centric fusion is present. Data obtained by geometric morphometrics enable a clear morphological distinction among the three species, as well as in relation to two other species of the genus Caranx and Oligoplites. Data obtained suggest that morphologic evolution in Selene species was primarily dissociated from visible changes that occurred at the chromosomal level.  相似文献   
995.
One solution to the shortage of human organs available for transplantation envisions growing new organs in situ. This can be accomplished by transplantation of developing organ anlagen/primordia. Allotransplantation of embryonic day 15 metanephroi into the omentum of adult hosts is followed by differentiation, growth, vascularization and function of the implants. Here we show that survival of rats with all native renal mass removed can be increased by prior metanephros transplantation and ureteroureterostomy. Excretion of urine formed by metanephroi is prerequisite for enhanced survival. This is the first demonstration that life can be extended following de novo renal organogenesis.  相似文献   
996.
Although lung disease is the major cause of mortality in cystic fibrosis (CF), gastrointestinal (GI) manifestations are the first hallmarks in 15–20% of affected newborns presenting with meconium ileus, and remain major causes of morbidity throughout life. We have previously shown that cGMP-dependent phosphodiesterase type 5 (PDE5) inhibitors rescue defective CF Transmembrane conductance Regulator (CFTR)-dependent chloride transport across the mouse CF nasal mucosa. Using F508del-CF mice, we examined the transrectal potential difference 1 hour after intraperitoneal injection of the PDE5 inhibitor vardenafil or saline to assess the amiloride-sensitive sodium transport and the chloride gradient and forskolin-dependent chloride transport across the GI tract. In the same conditions, we performed immunohistostaining studies in distal colon to investigate CFTR expression and localization. F508del-CF mice displayed increased sodium transport and reduced chloride transport compared to their wild-type littermates. Vardenafil, applied at a human therapeutic dose (0.14 mg/kg) used to treat erectile dysfunction, increased chloride transport in F508del-CF mice. No effect on sodium transport was detected. In crypt colonocytes of wild-type mice, the immunofluorescence CFTR signal was mostly detected in the apical cell compartment. In F508del-CF mice, a 25% reduced signal was observed, located mostly in the subapical region. Vardenafil increased the peak of intensity of the fluorescence CFTR signal in F508del-CF mice and displaced it towards the apical cell compartment. Our findings point out the intestinal mucosa as a valuable tissue to study CFTR transport function and localization and to evaluate efficacy of therapeutic strategies in CF. From our data we conclude that vardenafil mediates potentiation of the CFTR chloride channel and corrects mislocalization of the mutant protein. The study provides compelling support for targeting the cGMP signaling pathway in CF pharmacotherapy.  相似文献   
997.
998.

Introduction

Buruli Ulcer (BU) is caused by the environmental microbe Mycobacterium ulcerans. Despite unclear transmission, contact with a BU endemic region is the key known risk factor. In Victoria, Australia, where endemic areas have been carefully mapped, we aimed to estimate the Incubation Period (IP) of BU by interviewing patients who reported defined periods of contact with an endemic area prior to BU diagnosis.

Method

A retrospective review was undertaken of 408 notifications of BU in Victoria from 2002 to 2012. Telephone interviews using a structured questionnaire and review of notification records were performed. Patients with a single visit exposure to a defined endemic area were included and the period from exposure to disease onset determined (IP).

Results

We identified 111 of 408 notified patients (27%) who had a residential address outside a known endemic area, of whom 23 (6%) reported a single visit exposure within the previous 24 months. The median age of included patients was 30 years (range: 6 to 73) and 65% were male. 61% had visited the Bellarine Peninsula, currently the most active endemic area. The median time from symptom onset to diagnosis was 71 days (range: 34–204 days). The midpoint of the reported IP range was utilized to calculate a point estimate of the IP for each case. Subsequently, the mean IP for the cohort was calculated at 135 days (IQR: 109–160; CI 95%: 113.9–156), corresponding to 4.5 months or 19.2 weeks. The shortest IP recorded was 32 days and longest 264 days (Figure 1 & 2). IP did not vary for variables investigated.Open in a separate windowFigure 1Geographic representation of Bellarine Peninsula, considered endemic for BU as of 2012.Bellarine Peninsula – east of line from Geelong to Torquay. Mornington and Westernport – southwest of line from Hampton to Tooradin (including Phillip Island).Open in a separate windowFigure 2Geographic representation of East Gippsland, considered endemic for BU as of 2012.East Gippsland: East of Sale and south of the great divide.

Conclusions

The estimated mean IP of BU in Victoria is 135 days (IQR: 109–160 days), 4.5 months. The shortest recorded was IP 34 days and longest 264 days. A greater understanding of BU IP will aid clinical risk assessment and future research.  相似文献   
999.

Objective

This study aimed external validation of a formerly developed prediction model identifying children at risk for hearing loss after bacterial meningitis (BM). Independent risk factors included in the model are: duration of symptoms prior to admission, petechiae, cerebral spinal fluid (CSF) glucose level, Streptococcus pneumoniae and ataxia. Validation helps to evaluate whether the model has potential in clinical practice.

Study design

116 Dutch school-age BM survivors were included in the validation cohort and screened for sensorineural hearing loss (>25 dB). Risk factors were obtained from medical records. The model was applied to the validation cohort and its performance was compared with the development cohort. Validation was performed by application of the model on the validation cohort and by assessment of discrimination and goodness of fit. Calibration was evaluated by testing deviations in intercept and slope. Multiple imputation techniques were used to deal with missing values.

Results

Risk factors were distributed equally between both cohorts. Discriminative ability (Area Under the Curve, AUC) of the model was 0.84 in the development and 0.78 in the validation cohort. Hosmer-Lemeshow test for goodness of fit was not significant in the validation cohort, implying good fit concerning the similarity of expected and observed cases. There were no significant differences in calibration slope and intercept. Sensitivity and negative predicted value were high, while specificity and positive predicted value were low which is comparable with findings in the development cohort.

Conclusions

Performance of the model remained good in the validation cohort. This prediction model might be used as a screening tool and can help to identify those children that need special attention and a long follow-up period or more frequent auditory testing.  相似文献   
1000.

Background

Viral suppression and viral breakthrough impact the humoral immune response to HIV infection. We evaluated the impact of viral suppression and viral breakthrough on results obtained with two cross-sectional HIV incidence assays.

Methods

All samples were collected from adults in the US who were HIV infected for >2 years. Samples were tested with the BED capture enzyme immunoassay (BED-CEIA) which measures the proportion of IgG that is HIV-specific, and with an antibody avidity assay based on the Genetic Systems 1/2+ O ELISA. We tested 281 samples: (1) 30 samples from 18 patients with natural control of HIV-1 infection known as elite controllers or suppressors (2) 72 samples from 18 adults on antiretroviral therapy (ART), with 1 sample before and 2–6 samples after ART initiation, and (3) 179 samples from 20 virally-suppressed adults who had evidence of viral breakthrough receiving ART (>400 copies/ml HIV RNA) and with subsequent viral suppression.

Results

For elite suppressors, 10/18 had BED-CEIA values <0.8 normalized optical density units (OD-n) and these values did not change significantly over time. For patients receiving ART, 14/18 had BED-CEIA values that decreased over time, with a median decrease of 0.42 OD-n (range 0.10 to 0.63)/time point receiving ART. Three patterns of BED-CEIA values were observed during viral breakthrough: (1) values that increased then returned to pre-breakthrough values when viral suppression was re-established, (2) values that increased after viral breakthrough, and (3) values that did not change with viral breakthrough.

Conclusions

Viral suppression and viral breakthrough were associated with changes in BED-CEIA values, reflecting changes in the proportion of HIV-specific IgG. These changes can result in misclassification of patients with long-term HIV infection as recently infected using the BED-CEIA, thereby influencing a falsely high value for cross-sectional incidence estimates.  相似文献   
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