102 research outputs found
Resilience to Disturbance Despite Limited Dispersal and Self-Recruitment in Tropical Barrel Sponges: Implications for Conservation and Management
While estimates of connectivity are important for effective management, few such estimates are available for reef invertebrates other than for corals. Barrel sponges are one of the largest and most conspicuous members of the coral reef fauna across the Indo-Pacific and given their large size, longevity and ability to process large volumes of water, they have a major role in reef functioning. Here we used a panel of microsatellite markers to characterise the genetic structure of two barrel sponge species, Xestospongia testudinaria and a currently undescribed Xestospongia species. We sampled across seven populations in the Wakatobi Marine National Park, SE Sulawesi (Indonesia) spanning a spatial scale of approximately 2 to 70 km, and present the first estimates of demographic connectivity for coral reef sponges. Genetic analyses showed high levels of genetic differentiation between all populations for both species, but contrasting patterns of genetic structuring for the two species. Autocorrelation analyses showed the likely dispersal distances of both species to be in the order of 60 and 140 m for Xestopongia sp. and Xestospongia testudinaria, respectively, which was supported by assignment tests that showed high levels of self-recruitment (>80%). We also found consistently high inbreeding coefficients across all populations for both species. Our study highlights the potential susceptibility of barrel sponges to environmental perturbations because they are generally long-lived, slow growing, have small population sizes and are likely to be reliant on self-recruitment. Surprisingly, despite these features we actually found the highest abundance of both barrel sponge species (although they were generally smaller) at a site that has been severely impacted by humans over the last fifty years. This suggests that barrel sponges exhibit environmental adaptation to declining environmental quality and has important implications for the management and conservation of these important reef species. © 2014 Bell et al
The distal fascicle of the anterior inferior tibiofibular ligament as a cause of tibiotalar impingement syndrome: a current concepts review
Impingement syndromes of the ankle involve either osseous or soft tissue impingement and can be anterior, anterolateral, or posterior. Ankle impingement syndromes are painful conditions caused by the friction of joint tissues, which are both the cause and the effect of altered joint biomechanics. The distal fascicle of the anterior inferior tibiofibular ligament (AITFL) is possible cause of anterior impingement. The objective of this article was to review the literature concerning the anatomy, pathogenesis, symptoms and treatment of the AITFL impingement and finally to formulate treatment recommendations. The AITFL starts from the distal tibia, 5Â mm in average above the articular surface, and descends obliquely between the adjacent margins of the tibia and fibula, anterior to the syndesmosis to the anterior aspect of the lateral malleolus. The incidence of the accessory fascicle differs very widely in the several studies. The presence of the distal fascicle of the AITFL and also the contact with the anterolateral talus is probably a normal finding. It may become pathological, due to anatomical variations and/or anterolateral instability of the ankle resulting from an anterior talofibular ligament injury. When observed during an ankle arthroscopy, the surgeon should look for the criteria described to decide whether it is pathological and considering resection of the distal fascicle. The presence of the AITFL and the contact with the talus is a normal finding. An impingement of the AITFL can result from an anatomical variant or anteroposterior instability of the ankle. The diagnosis of ligamentous impingement in the anterior aspect of the ankle should be considered in patients who have chronic ankle pain in the anterolateral aspect of the ankle after an inversion injury and have a stable ankle, normal plain radiographs, and isolated point tenderness on the anterolateral aspect of the talar dome and in the anteroinferior tibiofibular ligament. The impingement syndrome can be treated arthroscopically
Association of HbA1c Values with Mortality and Cardiovascular Events in Diabetic Dialysis Patients. The INVOR Study and Review of the Literature
BACKGROUND: Improved glycemic control reduces complications in patients with diabetes mellitus (DM). However, it is discussed controversially whether patients with diabetes mellitus and end-stage renal disease benefit from strict glycemic control. METHODS: We followed 78 patients with DM initiating dialysis treatment of the region of Vorarlberg in a prospective cohort study applying a time-dependent Cox regression analysis using all measured laboratory values for up to more than seven years. This resulted in 880 HbA(1c) measurements (with one measurement every 3.16 patient months on average) during the entire observation period. Non-linear P-splines were used to allow flexible modeling of the association with mortality and cardiovascular disease (CVD) events. RESULTS: We observed a decreased mortality risk with increasing HbA(1c) values (HR = 0.72 per 1% increase, p = 0.024). Adjustment for age and sex and additional adjustment for other CVD risk factors only slightly attenuated the association (HR = 0.71, p = 0.044). A non-linear P-spline showed that the association did not follow a fully linear pattern with a highly significant non-linear component (p = 0.001) with an increased risk of all-cause mortality for HbA(1c) values up to 6-7%. Causes of death were associated with HbA(1c) values. The risk for CVD events, however, increased with increasing HbA(1c) values (HR = 1.24 per 1% increase, p = 0.048) but vanished after extended adjustments. CONCLUSIONS: This study considered the entire information collected on HbA(1c) over a period of more than seven years. Besides the methodological advantages our data indicate a significant inverse association between HbA(1c) levels and all-cause mortality. However, for CVD events no significant association could be found
Enzymatic capacities of metabolic fuel use in cuttlefish (Sepia officinalis) and responses to food deprivation: insight into the metabolic organization and starvation survival strategy of cephalopods
Food limitation is a common challenge for animals. Cephalopods are sensitive to starvation because of high metabolic rates and growth rates related to their "live fast, die young" life history. We investigated how enzymatic capacities of key metabolic pathways are modulated during starvation in the common cuttlefish (Sepia officinalis) to gain insight into the metabolic organization of cephalopods and their strategies for coping with food limitation. In particular, lipids have traditionally been considered unimportant fuels in cephalopods, yet, puzzlingly, many species (including cuttlefish) mobilize the lipid stores in their digestive gland during starvation. Using a comprehensive multi-tissue assay of enzymatic capacities for energy metabolism, we show that, during long-term starvation (12 days), glycolytic capacity for glucose use is decreased in cuttlefish tissues, while capacities for use of lipid-based fuels (fatty acids and ketone bodies) and amino acid fuels are retained or increased. Specifically, the capacity to use the ketone body acetoacetate as fuel is widespread across tissues and gill has a previously unrecognized capacity for fatty acid catabolism, albeit at low rates. The capacity for de novo glucose synthesis (gluconeogenesis), important for glucose homeostasis, likely is restricted to the digestive gland, contrary to previous reports of widespread gluconeogenesis among cephalopod tissues. Short-term starvation (3-5 days) had few effects on enzymatic capacities. Similar to vertebrates, lipid-based fuels, putatively mobilized from fat stores in the digestive gland, appear to be important energy sources for cephalopods, especially during starvation when glycolytic capacity is decreased perhaps to conserve available glucose
Clinical knee findings in floor layers with focus on meniscal status
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to examine the prevalence of self-reported and clinical knee morbidity among floor layers compared to a group of graphic designers, with special attention to meniscal status.</p> <p>Methods</p> <p>We obtained information about knee complaints by questionnaire and conducted a bilateral clinical and radiographic knee examination in 134 male floor layers and 120 male graphic designers. After the exclusion of subjects with reports of earlier knee injuries the odds ratio (OR) with 95% confidence intervals (CI) of knee complaints and clinical findings were computed among floor layers compared to graphic designers, using logistic regression. Estimates were adjusted for effects of body mass index, age and knee straining sports. Using radiographic evaluations, we conducted side-specific sensitivity analyses regarding clinical signs of meniscal lesions after the exclusion of participants with tibiofemoral (TF) osteoarthritis (OA).</p> <p>Results</p> <p>Reports of knee pain (OR = 2.7, 95% CI = 1.5–4.6), pain during stair walking (OR = 2.2, 95% CI = 1.3–3.9) and symptoms of catching of the knee joint (OR = 2.9, 95% CI = 1.4–5.7) were more prevalent among floor layers compared to graphic designers. Additionally, significant more floor layers than graphic designers had clinical signs suggesting possible meniscal lesions: a positive McMurray test (OR = 2.4, 95% CI = 1.1–5.0) and TF joint line tenderness (OR = 5.4, 95% CI = 2.4–12.0). Excluding floor layers (n = 22) and graphic designers (n = 15) with radiographic TF OA did not alter this trend between the two study groups: a positive McMurray test (OR = 2.2, 95% CI = 1.0–4.9), TF joint line tenderness (OR = 5.0, 95% CI = 2.0–12.5).</p> <p>Conclusion</p> <p>Results indicate that floor layers have a high prevalence of both self-reported and clinical knee morbidity. Clinical knee findings suggesting possible meniscal lesions were significant more prevalent among floor layers compared to a group of low-level exposed graphic designers and an association with occupational kneeling could be possible. However, causality cannot be confirmed due to the cross-sectional study design.</p
Clinical knee findings in floor layers with focus on meniscal status
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to examine the prevalence of self-reported and clinical knee morbidity among floor layers compared to a group of graphic designers, with special attention to meniscal status.</p> <p>Methods</p> <p>We obtained information about knee complaints by questionnaire and conducted a bilateral clinical and radiographic knee examination in 134 male floor layers and 120 male graphic designers. After the exclusion of subjects with reports of earlier knee injuries the odds ratio (OR) with 95% confidence intervals (CI) of knee complaints and clinical findings were computed among floor layers compared to graphic designers, using logistic regression. Estimates were adjusted for effects of body mass index, age and knee straining sports. Using radiographic evaluations, we conducted side-specific sensitivity analyses regarding clinical signs of meniscal lesions after the exclusion of participants with tibiofemoral (TF) osteoarthritis (OA).</p> <p>Results</p> <p>Reports of knee pain (OR = 2.7, 95% CI = 1.5–4.6), pain during stair walking (OR = 2.2, 95% CI = 1.3–3.9) and symptoms of catching of the knee joint (OR = 2.9, 95% CI = 1.4–5.7) were more prevalent among floor layers compared to graphic designers. Additionally, significant more floor layers than graphic designers had clinical signs suggesting possible meniscal lesions: a positive McMurray test (OR = 2.4, 95% CI = 1.1–5.0) and TF joint line tenderness (OR = 5.4, 95% CI = 2.4–12.0). Excluding floor layers (n = 22) and graphic designers (n = 15) with radiographic TF OA did not alter this trend between the two study groups: a positive McMurray test (OR = 2.2, 95% CI = 1.0–4.9), TF joint line tenderness (OR = 5.0, 95% CI = 2.0–12.5).</p> <p>Conclusion</p> <p>Results indicate that floor layers have a high prevalence of both self-reported and clinical knee morbidity. Clinical knee findings suggesting possible meniscal lesions were significant more prevalent among floor layers compared to a group of low-level exposed graphic designers and an association with occupational kneeling could be possible. However, causality cannot be confirmed due to the cross-sectional study design.</p
Association of Ficolin-3 with Severity and Outcome of Chronic Heart Failure
BACKGROUND: Inflammatory mechanisms involving complement activation has been shown to take part in the pathophysiology of congestive heart failure, but the initiating mechanisms are unknown. We hypothesized that the main initiator molecules of the lectin complement pathway mannose-binding lectin (MBL), ficolin-2 and ficolin-3 were related to disease severity and outcome in chronic heart failure. METHODS AND RESULTS: MBL, ficolin-2 and ficolin-3 plasma concentrations were determined in two consecutive cohorts comprising 190 patients from Hungary and 183 patients from Norway as well as controls. Disease severity and clinical parameters were determined at baseline, and all-cause mortality was registered after 5-years follow-up. In univariate analysis a low level of ficolin-3, but not that of MBL or ficolin-2, was significantly associated with advanced heart failure (New York Heart Association Class IV, p<0.001 for both cohorts) and showed inverse correlation with B- type natriuretic peptide (BNP) levels (r = -0.609, p<0.001 and r = -0.467, p<0.001, respectively). In multivariable Cox regression analysis, adjusted for age, gender and BNP, decreased plasma ficolin-3 was a significant predictor of mortality (HR 1.368, 95% CI 1.052-6.210; and HR 1.426, 95% CI 1.013-2.008, respectively). Low ficolin-3 levels were associated with increased complement activation product C3a and correspondingly decreased concentrations of complement factor C3. CONCLUSIONS: This study provides evidence for an association of low ficolin-3 levels with advanced heart failure. Concordant results from two cohorts show that low levels of ficolin-3 are associated with advanced heart failure and outcome. The decrease of ficolin-3 was associated with increased complement activation
Refined human artificial chromosome vectors for gene therapy and animal transgenesis
Human artificial chromosomes (HACs) have several advantages as gene therapy vectors, including stable episomal maintenance, and the ability to carry large gene inserts. We previously developed HAC vectors from the normal human chromosomes using a chromosome engineering technique. However, endogenous genes were remained in these HACs, limiting their therapeutic applications. In this study, we refined a HAC vector without endogenous genes from human chromosome 21 in homologous recombination-proficient chicken DT40 cells. The HAC was physically characterized using a transformation-associated recombination (TAR) cloning strategy followed by sequencing of TAR-bacterial artificial chromosome clones. No endogenous genes were remained in the HAC. We demonstrated that any desired gene can be cloned into the HAC using the Cre-loxP system in Chinese hamster ovary cells, or a homologous recombination system in DT40 cells. The HAC can be efficiently transferred to other type of cells including mouse ES cells via microcell-mediated chromosome transfer. The transferred HAC was stably maintained in vitro and in vivo. Furthermore, tumor cells containing a HAC carrying the suicide gene, herpes simplex virus thymidine kinase (HSV-TK), were selectively killed by ganciclovir in vitro and in vivo. Thus, this novel HAC vector may be useful not only for gene and cell therapy, but also for animal transgenesis
Tolerance of sponge assemblages to temperature anomalies: resilience and proliferation of sponges following the 1997-8 El-Niño southern oscillation.
Coral reefs across the world are under threat from a range of stressors, and while there has been considerable focus on the impacts of these stressors on corals, far less is known about their effect on other reef organisms. The 1997-8 El-Niño Southern Oscillation (ENSO) had notable and severe impacts on coral reefs worldwide, but not all reef organisms were negatively impacted by this large-scale event. Here we describe how the sponge fauna at Bahia, Brazil was influenced by the 1997-8 ENSO event. Sponge assemblages from three contrasting reef habitats (reef tops, walls and shallow banks) at four sites were assessed annually from 1995 to 2011. The within-habitat sponge diversity did not vary significantly across the study period; however, there was a significant increase in density in all habitats. Multivariate analyses revealed no significant difference in sponge assemblage composition (ANOSIM) between pre- and post-ENSO years for any of the habitats, suggesting that neither the 1997-8 nor any subsequent smaller ENSO events have had any measurable impact on the reef sponge assemblage. Importantly, this is in marked contrast to the results previously reported for a suite of other taxa (including corals, echinoderms, bryozoans, and ascidians), which all suffered mass mortalities as a result of the ENSO event. Our results suggest that of all reef taxa, sponges have the potential to be resilient to large-scale thermal stress events and we hypothesize that sponges might be less affected by projected increases in sea surface temperature compared to other major groups of reef organisms
Reduced Diversity and High Sponge Abundance on a Sedimented Indo-Pacific Reef System: Implications for Future Changes in Environmental Quality
Although coral reef health across the globe is declining as a result of anthropogenic impacts, relatively little is known of how environmental variability influences reef organisms other than corals and fish. Sponges are an important component of coral reef fauna that perform many important functional roles and changes in their abundance and diversity as a result of environmental change has the potential to affect overall reef ecosystem functioning. In this study, we examined patterns of sponge biodiversity and abundance across a range of environments to assess the potential key drivers of differences in benthic community structure. We found that sponge assemblages were significantly different across the study sites, but were dominated by one species Lamellodysidea herbacea (42% of all sponges patches recorded) and that the differential rate of sediment deposition was the most important variable driving differences in abundance patterns. Lamellodysidea herbacea abundance was positively associated with sedimentation rates, while total sponge abundance excluding Lamellodysidea herbacea was negatively associated with rates of sedimentation. Overall variation in sponge assemblage composition was correlated with a number of variables although each variable explained only a small amount of the overall variation. Although sponge abundance remained similar across environments, diversity was negatively affected by sedimentation, with the most sedimented sites being dominated by a single sponge species. Our study shows how some sponge species are able to tolerate high levels of sediment and that any transition of coral reefs to more sedimented states may result in a shift to a low diversity sponge dominated system, which is likely to have subsequent effects on ecosystem functioning. © 2014 Powell et al
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