Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 29
Filter
1.
Mar Environ Res ; 169: 105399, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34175523

ABSTRACT

Overfishing is a key stressor in many coral reefs, affecting their function and ecosystem services. In the Gulf of California, 50 years of artisanal and recreational fishing have removed most of the largest and most vulnerable fish species, the Espiritu Santo Archipelago (ESA) is a marine protected area (MPA) where artisanal and recreational fishing are allowed in most of the natural reefs, while the artificial reefs (wrecks) are fully protected. An important question under such circumstances is whether artificial reefs can serve as surrogate habitats for the natural reefs. To address this question, we characterized the fish community (species richness, abundance, differences in taxonomic structure) and analyzed the obtained data by multivariate ordination and similarity analysis. The highest species richness was found in the artificial reefs, with total of 83 species, of which 21 species were exclusive. Contrary to the species richness, the total fish abundance was 20% higher at the natural reefs. The fish assemblages of the artificial reefs differ significantly from those of the natural reefs. The natural reefs of the ESA are dominated by few fish species from families of lower trophic levels. In contrast, the studied shipwrecks provide refuge to commercially important fish species (such as Snappers, Triggerfish, Jacks, and Groupers) including threatened species. The different fish compositions on the natural and artificial reefs is likely to be the outcome of differential fishing pressure. The non-fished areas (wrecks) of the ESA may represent a good strategy for reef restoration, enhanced fishing grounds (via spillover) and fishing management. However, the fish community structure of the artificial reefs differs from natural rocky reefs of the ESA, and therefore, should not be considered as surrogate habitats for natural reefs. The results point out the need to reassess the management effectiveness of the natural reefs of the ESA.


Subject(s)
Conservation of Natural Resources , Ecosystem , Animals , Coral Reefs , Fisheries , Fishes , Seafood
2.
Ecology ; 101(2): e02925, 2020 02.
Article in English | MEDLINE | ID: mdl-31660585

ABSTRACT

Climate change and bioinvasions are two facets of global change that can act in tandem to impact native species and ecosystems. However, their combined effects on key species have rarely been studied. The Mediterranean Sea is a hot spot of both ocean warming and bioinvasions, where their impact can be tested together. In recent years, the population of a key herbivore, the European purple sea urchin (Paracentrotus lividus), has virtually collapsed along the Israeli Mediterranean coast (southeastern Levant). Here, we used field and lab experiments to test two complementary hypotheses that may explain the urchin population collapse: (1) resource competition that may lead to competitive exclusion by invasive grazers (two Red Sea rabbitfishes) and (2) reduced performance due to ocean warming. An inclusion-exclusion in situ caging experiment revealed a strong negative impact of fish grazing on algal cover and on the urchin's gut content and gonado-somatic index (GSI). Laboratory experiments revealed a considerable negative impact of both elevated temperature and food deficiency on sea urchin respiration and GSI, and consequently on its energy budget and reproductive potential and, potentially, fitness. Such reduced reproductive capacity must have greatly lowered the sea urchin's population viability, contributing (and possibly even leading) to its collapse in the southeastern Levant in the past two decades. Urchin population declines are expected to spread to the west and north of the Mediterranean Sea following further warming and rabbitfish expansion. This study is the first to demonstrate the potential additive effects of ocean warming and implied competitive exclusion by an invader on a native species at its warm biogeographic distribution edge.


Subject(s)
Ecosystem , Herbivory , Animals , Climate Change , Oceans and Seas , Sea Urchins , Temperature
3.
Conserv Biol ; 30(6): 1182-1191, 2016 12.
Article in English | MEDLINE | ID: mdl-26991947

ABSTRACT

Marine protected areas (MPAs) are a commonly applied solution to coral reef degradation, yet coral reefs continue to decline worldwide. We argue that expanding the range of MPAs to include degraded reefs (DR-MPA) could help reverse this trend. This approach requires new ecological criteria for MPA design, siting, and management. Rather than focusing solely on preserving healthy reefs, our approach focuses on the potential for biodiversity recovery and renewal of ecosystem services. The new criteria would help identify sites with the highest potential for recovery and the greatest resistance to future threats (e.g., increased temperature and acidification) and sites that contribute to MPA connectivity. The DR-MPA approach is a compliment rather than a substitute for traditional MPA design approaches. We believe that the DR-MPA approach can enhance the natural, or restoration-assisted, recovery of DRs and their ecosystem services; increase total reef area available for protection; promote more resilient and better-connected MPA networks; and improve conditions for human communities dependent on MPA ecosystem services.


Subject(s)
Conservation of Natural Resources , Coral Reefs , Animals , Anthozoa , Biodiversity , Ecosystem , Humans
4.
Osteoporos Int ; 24(1): 263-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22736069

ABSTRACT

UNLABELLED: This study aims to estimate bisphosphonate effectiveness by comparing fracture incidence over time on therapy in glucocorticoid-induced osteoporosis (GIO). From this observational study, alendronate and risedronate decreased clinical vertebral and nonvertebral fractures over time. The effectiveness of each bisphosphonate is consistent with their efficacies demonstrated on surrogate markers in randomized controlled trials (RCTs). INTRODUCTION: This study aims to estimate bisphosphonate effectiveness by comparing fracture incidence over time on therapy with fracture incidence during a short period after starting a therapy. METHODS: The study population was a subgroup of a larger cohort study comprising two cohorts of women aged ≥65 years, prescribed with alendronate or risedronate. Within the two study cohorts, 11,007 women were identified as having received glucocorticoids. Within each cohort, the baseline incidence of clinical fractures at nonvertebral and vertebral sites was defined by the initial 3-month period after starting therapy. Relative to these baseline data, we then compared the fracture incidence during the subsequent 12 months on therapy. RESULTS: The baseline incidence of clinical nonvertebral and vertebral fractures was similar in the alendronate cohort (5.22 and 5.79/100 person-years, respectively) and in the risedronate cohort (5.51 and 5.68/100 person-years, respectively). Relative to the baseline incidence, fracture incidence was significantly lower in the subsequent 12 months in both cohorts of alendronate (33 % lower at nonvertebral sites and 59 % at vertebral sites) and risedronate (28 % lower at nonvertebral sites and 54 % at vertebral sites). CONCLUSION: From this observational study not designed to compare drugs, both alendronate and risedronate decreased clinical vertebral and nonvertebral fractures over time. The reductions observed in fracture incidence, within each cohort, suggest that the effectiveness of each bisphosphonate in clinical practice is consistent with their efficacies demonstrated on surrogate markers in randomized controlled trials.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Diphosphonates/therapeutic use , Glucocorticoids/adverse effects , Osteoporosis, Postmenopausal/chemically induced , Osteoporotic Fractures/prevention & control , Administration, Oral , Aged , Alendronate/therapeutic use , Bone Density Conservation Agents/administration & dosage , Diphosphonates/administration & dosage , Etidronic Acid/analogs & derivatives , Etidronic Acid/therapeutic use , Female , Follow-Up Studies , France/epidemiology , Humans , Incidence , Osteoporosis, Postmenopausal/drug therapy , Osteoporosis, Postmenopausal/epidemiology , Osteoporotic Fractures/chemically induced , Osteoporotic Fractures/epidemiology , Risedronic Acid
5.
Osteoporos Int ; 21(6): 1021-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-19722103

ABSTRACT

SUMMARY: There are differences in the risk profile of patients prescribed alendronate, risedronate, or ibandronate. Observed reductions in fracture incidence over time suggest that the effectiveness of each bisphosphonate in clinical practice has been consistent with their efficacies demonstrated in randomized controlled trials. INTRODUCTION: Observational studies of bisphosphonate effectiveness for fracture prevention are subject to bias from unknown characteristics of baseline fracture risk at the start of therapy. The fracture incidence during the short period after starting a bisphosphonate and before any expected clinical benefit likely reflects baseline fracture risk. Bisphosphonate effectiveness may then be estimated by measuring the change in fracture incidence over time on therapy. METHODS: Administrative billing data were used to follow three cohorts of women aged 65 and older (total n = 210,144) after starting therapy either on alendronate, risedronate, or ibandronate in the USA between market introduction and 2006. Within each cohort, the baseline incidence of clinical fractures at the hip, vertebral, and nonvertebral sites was defined by the initial 3-month period after starting therapy. Relative to these baselines, we then compared the fracture incidence during the subsequent 12 months on therapy. RESULTS: At the start of therapy, the ibandronate cohort was younger and had fewer prior fractures than either the risedronate or alendronate cohorts. Accordingly, the baseline incidence of hip fractures was higher in the risedronate cohort (0.90 per 100 person-years) and in the alendronate cohort (0.77) than in the ibandronate cohort (0.64). Relative to the baseline incidence, fracture incidence was significantly lower in the subsequent 12 months in both cohorts of alendronate (18% lower at hip, 28% at nonvertebral sites, and 57% at vertebral sites) and risedronate (27% lower at hip, 21% at nonvertebral sites, and 54% at vertebral sites). In the ibandronate cohort, the fracture incidence was lower (31%) only at vertebral sites. CONCLUSIONS: Differences in the baseline fracture incidence among the cohorts may reflect differences in the risk profile of patients prescribed each bisphosphonate. The reductions observed in fracture incidence over time within each cohort suggest that the effectiveness of each bisphosphonate in clinical practice has been consistent with their efficacies demonstrated in randomized controlled trials.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Diphosphonates/therapeutic use , Osteoporotic Fractures/prevention & control , Age Factors , Aged , Alendronate/therapeutic use , Epidemiologic Methods , Etidronic Acid/analogs & derivatives , Etidronic Acid/therapeutic use , Female , Hip Fractures/epidemiology , Hip Fractures/prevention & control , Humans , Ibandronic Acid , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/drug therapy , Osteoporosis, Postmenopausal/epidemiology , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/etiology , Risedronic Acid , United States/epidemiology
6.
Ann Rheum Dis ; 68(11): 1746-53, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19019891

ABSTRACT

OBJECTIVES: To confirm and define the genetic association of STAT4 and systemic lupus erythematosus (SLE), investigate the possibility of correlations with differential splicing and/or expression levels, and genetic interaction with IRF5. METHODS: 30 tag SNPs were genotyped in an independent set of Spanish cases and controls. SNPs surviving correction for multiple tests were genotyped in five new sets of cases and controls for replication. STAT4 cDNA was analysed by 5'-RACE PCR and sequencing. Expression levels were measured by quantitative PCR. RESULTS: In the fine mapping, four SNPs were significant after correction for multiple testing, with rs3821236 and rs3024866 as the strongest signals, followed by the previously associated rs7574865, and by rs1467199. Association was replicated in all cohorts. After conditional regression analyses, two major independent signals, represented by SNPs rs3821236 and rs7574865, remained significant across the sets. These SNPs belong to separate haplotype blocks. High levels of STAT4 expression correlated with SNPs rs3821236, rs3024866 (both in the same haplotype block) and rs7574865 but not with other SNPs. Transcription of alternative tissue-specific exons 1, indicating the presence of tissue-specific promoters of potential importance in the expression of STAT4, was also detected. No interaction with associated SNPs of IRF5 was observed using regression analysis. CONCLUSIONS: These data confirm STAT4 as a susceptibility gene for SLE and suggest the presence of at least two functional variants affecting levels of STAT4. The results also indicate that the genes STAT4 and IRF5 act additively to increase the risk for SLE.


Subject(s)
Interferon Regulatory Factors/genetics , Lupus Erythematosus, Systemic/genetics , STAT4 Transcription Factor/genetics , Adult , Alternative Splicing , Case-Control Studies , Child , Gene Expression Regulation , Genetic Predisposition to Disease , Genotype , Humans , Lupus Erythematosus, Systemic/blood , Polymorphism, Single Nucleotide , RNA, Messenger/genetics , STAT4 Transcription Factor/blood
7.
Mar Pollut Bull ; 56(3): 430-8, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18155069

ABSTRACT

Coastal marine reserves in general, and coral reef reserves in particular, are typically composed of scattered patches separated by uninhabited areas. Due to the sessile mode of life of adult corals, larval connectivity is often the only agent of gene flow between reef localities. In this study we examined the connectivity between populations of the common scleratinian coral Stylophora pistillata at the northern tip of the Gulf of Aqaba (Red Sea), using the rDNA ITS (internal transcribed spacer) as a molecular marker. Sequence comparisons among recruits indicated very similar, equally-diverse, assemblages of recruits in both the northern (highly affected by anthropogenic disturbances) and southern (less affected) study sites, implying a high larval connectivity or common sources of larval supply. By contrast, sequence diversity observed among adults declined sharply from southern to northern sites, accompanied by genetic differentiation of the respective populations. Based on Fu's Fs-test of selective neutrality, it may be suggested that various post-settlement selective regimes, presumably more intense in the northern sites, provide a reasonable explanation for the observed patterns of genetic diversity. The suggested hypothesis is supported by the sharper decline in sequence diversity found between recruits and adults in the northern sites. This study exemplifies the necessity to consider local selective factors, in addition to larval connectivity, when managing marine reserves.


Subject(s)
Anthozoa/genetics , Ecosystem , Environmental Monitoring , Genetic Structures , Marine Biology , Selection, Genetic , Animals , Anthozoa/physiology , Geography , Indian Ocean , Jordan , Population Dynamics
8.
Genes Immun ; 8(1): 69-74, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17136123

ABSTRACT

PDCD1, an immunoreceptor involved in peripheral tolerance has previously been shown to be genetically associated with systemic lupus erythematosus (SLE). PDCD1 has two ligands whose genes are located in close proximity on chromosome 9p24. Our attention was drawn to these ligands after finding suggestive linkage to a marker (gata62f03, Z=2.27) located close to their genes in a genome scan of Icelandic families multiplex for SLE. Here, we analyse Swedish trios (N=149) for 23 single nucleotide polymorphisms (SNPs) within the genes of the PDCD1 ligands. Initially, indication of association to eight SNPs was observed, and these SNPs were therefore also analysed in Mexican trios (N=90), as well as independent sets of patients and controls from Sweden (152 patients, 448 controls) and Argentina (288 patients, 288 controls). We do not find support for genetic association to SLE. This is the first genetic study of SLE and the PDCD1 ligands and the lack of association in several cohorts implies that these genes are not major risk factors for SLE.


Subject(s)
Antigens, CD/genetics , Antigens, CD/metabolism , Apoptosis Regulatory Proteins/metabolism , Genetic Predisposition to Disease , Intercellular Signaling Peptides and Proteins/genetics , Lupus Erythematosus, Systemic/genetics , Polymorphism, Single Nucleotide , B7-H1 Antigen , Female , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Ligands , Linkage Disequilibrium , Male , Programmed Cell Death 1 Ligand 2 Protein , Programmed Cell Death 1 Receptor
9.
Mar Pollut Bull ; 48(9-10): 954-60, 2004 May.
Article in English | MEDLINE | ID: mdl-15111043

ABSTRACT

The extensive deterioration of coral reefs worldwide highlights the importance of creating efficient monitoring methods to best assess their state of health. At present, several suggested parameters serve such indicators. None of these, however, is well accepted as reliably representing reef community health. In the present study we examine a new approach based on the ratio between mortality and recruitment rates of branching corals, which we term 'Deterioration Index' (DI). It aims at providing a quantitative indication of the state of health of reef-building coral communities. The method was developed and tested on 16 coral communities on artificially laid rocks along the coast of Eilat, Red Sea (Gulf of Aqaba). In contrast to frequently used indices (i.e. mortality rate, abundance and species richness), which did not demonstrate a consistent result in comparing disturbed vs. undisturbed coral communities, the DI revealed significant differences between these communities. Our results suggest that the use of the DI may enable the detection of disturbed coral communities in one instance monitoring, where the other parameters had failed. The DI, therefore, may provide a comparable quantitative assessment of the deterioration process and its intensity in a coral community. We propose the DI approach as an efficient and applicable tool for coral reef monitoring.


Subject(s)
Anthozoa/growth & development , Conservation of Natural Resources/methods , Environmental Monitoring/standards , Animals , Environmental Monitoring/methods , Mortality , Oceans and Seas , Population Dynamics , Reproduction/physiology
10.
Sci Total Environ ; 296(1-3): 139-51, 2002 Sep 16.
Article in English | MEDLINE | ID: mdl-12398332

ABSTRACT

Over the last two centuries, the marine life of the Eastern Mediterranean has been influenced by two major factors: one is beneficial, and concerns species migration, such as the opening of the Suez Canal, which enriched the impoverished eastern Mediterranean Sea with over 300 species of fish and invertebrates of Red Sea origin; while the other, a negative and possibly wider-reaching factor, is that of man-made pollution, which has induced unpredictable changes, destabilizing the biological world in both magnitude and duration. Initially cryptic, the effects caused by pollutants first occur at the biochemical and cellular levels of an organism, causing alterations and deviations from the normal, strongly mobilizing its defense systems. Conventional methodologies of ecological analyses, based on species and specimen numbers, cannot detect such alterations. Studying several mollusk populations from polluted and reference sites of the Red Sea and Mediterranean littoral of Israel, we used specific markers for in vivo and in vitro studies to expose the state of micronucleation; levels of defense transport systems such as membrane transport system of organic anions (SATOA) and organic cations (OCT); the state of the multi-xenobiotic resistance-mediating transporter (MXRtr). Based on fluorescent microscopy and microfluorometry, these markers offer powerful tools to expose cryptic changes in the affected populations and provide data necessary for planning and management to protect animal communities and preserve their biological diversity. Comparative analysis of general gene-expression in polluted and reference sites indicates that stress factors have differentially affected the various biological taxa and separated phenotypic sub-populations, producing a novel type of punctuated selection. Such factors, although negative in their influences, in some instances altering the qualities of organisms, and establishing alterations in their hereditary information, pre-adapt them to survive and succeed in new situations.


Subject(s)
Ecosystem , Fishes , Invertebrates , Water Pollutants/adverse effects , Adaptation, Physiological , Animals , Gene Expression Profiling , Mediterranean Region , Phenotype , Population Dynamics , Survival
11.
Psychol Rep ; 85(3 Pt 1): 880-2, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10672749

ABSTRACT

The study examined the influence of a lack of availability of respite care on the careers of 574 parents having children with disabilities. Among these parents, there was a relationship between age of child, severity of disability, and parents missing hours of work or passing up occupational opportunities. These findings have implications for advocating more available and accessible respite services and more in-depth study of the cost effectiveness of respite care on parental income and career progression.


Subject(s)
Delivery of Health Care/economics , Disabled Children , Respite Care/economics , Adolescent , Adult , Child , Employment , Humans , Middle Aged , Respite Care/standards , Surveys and Questionnaires
12.
Psychol Rep ; 80(3 Pt 2): 1167-70, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9246883

ABSTRACT

This study examined the perceived efficacy of interventions commonly used by teachers of students with behavior disorders. Of 30 interventions used with approximately 1200 students labeled behaviorally disordered, 149 teachers ranked 22 as effective, and 8 were more often ranked as seldom effective. These findings have implications for teachers' preparation and identifying better practices for teaching students with behavior disorders.


Subject(s)
Attitude , Behavior Therapy , Child Behavior Disorders/therapy , Students/psychology , Adolescent , Child , Child Behavior Disorders/psychology , Child, Preschool , Female , Humans , Iowa , Male , Teaching/methods , Treatment Outcome
13.
Biol Bull ; 189(3): 363-369, 1995 Dec.
Article in English | MEDLINE | ID: mdl-29244579

ABSTRACT

Infaunal soft-bottom invertebrates benefit from the presence of sediment, but sedimentation is potentially harmful for hard-bottom dwellers. Most sponges live on hard bottom, but on coral reefs in the Red Sea, the species Biemna ehrenbergi (Keller, 1889) is found exclusively in soft-bottom lagoons, usually in the shallowest part. This location is a sink environment, which increases the deposition of particulate organic matter. Most of the sponge body is covered by sediment, but the chimney-like siphons protrude from the sediment surface. The sponge is attached to the buried beach-rock, which reduces the risk of dislodgment during storms. Dye injected above and into the sediment revealed, for the first time, a sponge pumping interstitial water (rich with particles and nutrients) into its aquiferous system. Visual examination of plastic replicas of the aquiferous system and electron microscopical analysis of sponge tissue revealed that the transcellular ostia are mostly located on the buried surface of the sponge. The oscula, however, are located on top of the siphons; their elevated position and their ability to close combine to prevent the filtering system outflow from clogging. The transcellular ostia presumably remain open due to cellular mobility. The sponge maintains a large population of bacteriocytes, which contains bacteria of several different species. Some of these bacteria disintegrate, and may be consumed by the sponge.

14.
15.
Postgrad Med ; 83(7): 57-8, 61, 1988 May 15.
Article in English | MEDLINE | ID: mdl-2966932

ABSTRACT

Back pain often causes patients great despair, and they expect the primary care physician or orthopedic surgeon to provide a quick, simple solution. Rest and analgesia are the most commonly prescribed treatments, and muscle relaxants, heat, traction, and physiotherapy are also used. If these treatments do not help, the patient may search for relief through faith healing, acupuncture, chiropractic treatment, or other nonconventional forms of treatment. Although chiropractic treatment is a popular alternative, its long-term effect is questionable and the medical literature contains numerous reports of patients whose condition worsened as a result of it. Physicians should be aware of the dangers of chiropractic treatment, particularly in patients with severe spondylitic changes, osteoporosis, fractures, tumors, ankylosing spondylitis, infections, or signs of nerve root pressure.


Subject(s)
Back Pain/therapy , Chiropractic , Manipulation, Orthopedic/adverse effects , Back Pain/etiology , Cysts/complications , Humans , Male , Middle Aged , Spinal Cord Diseases/complications , Thrombosis/complications
18.
Percept Mot Skills ; 57(2): 567-70, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6634340

ABSTRACT

No significant differences in proficiency of reading-listening comprehension among 24 reading-disabled boys in Grades 4, 5, and 6 were noted after hearing "talking book," taped stories, and teacher-read presentations.


Subject(s)
Dyslexia/therapy , Tape Recording , Teaching Materials , Adolescent , Attention , Child , Dyslexia/psychology , Humans , Male , Music , Remedial Teaching
20.
Child Care Health Dev ; 7(6): 347-56, 1981.
Article in English | MEDLINE | ID: mdl-7326841

ABSTRACT

The Michigan Gender Identity Test (MGIT) was administered to 30 autistic children to determine whether autistic children could demonstrate a sense of gender identity. The results of the MGIT were correlated with other developmental indices obtained from the Alpern-Boll Developmental Profile. From this sample of autistics, a significant relationship was found between gender identity and mental age, chronological age, communication skills, physical skills, social skills, self-help skills and academic (cognitive skills.


Subject(s)
Autistic Disorder/psychology , Concept Formation , Gender Identity , Identification, Psychological , Child , Child, Preschool , Communication , Female , Humans , Intelligence , Male , Motor Skills , Self Care , Social Behavior
SELECTION OF CITATIONS
SEARCH DETAIL
...