43 research outputs found

    The Role of the threespot damselfish, Stegastes planifrons, in Contemporary Caribbean Reef Ecology

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    Caribbean reef ecosystems have undergone major ecological changes in the last 30 – 40 years, with the result that ecological systems once dominated by structurally complex Acropora cervicornis and Montastraea annularis corals now consist mainly of flattened carbonate substrates with macroalgal overgrowth. A need for greater understanding of coral reef ecosystems is imperative if we are to attempt to conserve them. The threespot damselfish, Stegastes planifrons, is herbivorous damselfish species ubiquitous to Caribbean reefs, where it has been termed a keystone species. Aggressive in nature, S. planifrons defends territories of around 70 cm in diameter from other roving herbivorous fish and urchins, in apparent effort to maintain the algal resources therein for its own use. The predilection of Stegastes planifrons for basing its territories on the now Critically Endangered staghorn coral, Acropora cervicornis, and the Endangered boulder coral Montastraea annularis is well known, however the likely ecological implications of this fact have not been investigated. Using a combination of experimental and observational methodologies we examine the ecological implications of coral microhabitat choice and use by S. planifrons. We also assess the magnitude of the direct and indirect effects of S. planifrons’ territorial behaviour on macroalgal dynamics both within and outside of territory confines, at the reef-wide level. We find that coral microhabitat is a more important determinant of algal community structure than damselfish presence, and that this can be explained by a previously unrecognised effect of coral microhabitat on the grazing behaviour of roving herbivorous fishes - on which S. planifrons’ territorial behaviour has little effect. In a modification of the space availability hypothesis of Williams et al (2001) we suggest that Acropora cervicornis acts as a grazing fish „exclusion zone‟, and we further hypothesise that the existence of large stands of this coral prior to the Caribbean „phase shift‟ may have acted to concentrate the grazing pressure of excluded roving fish onto the remaining areas of the reef. We further hypothesise that the loss of such „exclusion zones‟ and accompanied effective dilution of grazing pressure may have been on a scale large enough to have been a significant underlying factor in the proliferation of macroalgae seen on modern day Caribbean reefs. In the absence of demonstrable direct or indirect effects on benthic algal communities we question the continued keystone status of S. planifrons, particularly since the status 6 was originally based on interference behaviour involving the important grazing urchin Diadema antillarum, which is now functionally absent from Caribbean reefs. Implications of the context-dependant nature of keystone status are also discussed. We find that the effect of S. planifrons on coral community may be more important than its effects on benthic algal community. In examining the factors involved in habitat coral choice we establish a significant preference for 100% live coral substrate over substrates with a supply of algal food. Territory selection was followed by a high rate of coral biting – a behaviour which has previously been shown to result in coral tissue death and the fast establishment of algal turf communities on which S. planifrons likes to feed (Kaufman 1977). We also demonstrate a novel and significant association between S. planifrons presence and disease incidence its primary habitat coral, the Critically Endangered staghorn coral Acropora cervicornis, and a significant correlation between areas of fish biting and the later onset of disease. Changes to the overall role of damselfish on today's Caribbean reefs are discussed in light of these insights.NER

    Herpetic zoster folliculitis in the immunocompromised host

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    Introduction Exclusive involvement of herpes zoster (HZ) in the follicular epithelium occurs rarely and lacks the typical cutaneous and histopathologic findings associated with herpesvirus. We describe a patient who underwent adjuvant chemotherapy for pancreatic cancer and subsequently had a nonvesicular rash for several weeks, ultimately proving to be herpetic zoster folliculitis. Case report A 78-year-old man with adenocarcinoma of the tail of the pancreas treated with surgical resection and 1 round of adjuvant chemotherapy with gemcitabine, docetaxel, and capecitabine presented with a 3-week history of a right leg rash. He first noticed the rash 5 days after the initiation of his chemotherapy. It initially appeared on his middorsal foot, and over the next couple weeks progressed proximally along the anteromedial leg to the distal knee and medial thigh. It was not painful and was minimally pruritic. Two and a half weeks after the onset of his rash, a fever to 38.5°C developed along with back pain. At this time, he had a nondiagnostic skin biopsy by an outside dermatologist and was given diphenhydramine and topical hydrocortisone with no improvement in his rash. He also had an abdominal computed tomography (CT) performed at an outside hospital, which found a left upper quadrant fluid collection. He was subsequently admitted to Columbia Presbyterian Medical Center for evaluation. On our examination, he had purpuric patches and edematous, purpuric papules along the right dorsal foot, extending proximally up the right anteromedial leg (Fig 1). He also had a few faint pink papules along the right hip and superior buttock (Fig 2). There were no vesicles. A comprehensive metabolic panel and liver function test results were normal. Noted were a leukocytosis level of 14,400/μL with 76% neutrophils and 1% bands, an elevated lipase level of 194 U/L (3-43 U/L), and an amylase level of 95 U/L (20-96 U/L). A CT scan of the abdomen confirmed an 8.0- × 7.0-cm fluid collection of the left upper quadrant of the abdomen. A skin biopsy of the right anteromedial leg found only alteration of the basal layer epidermis with a perivascular mononuclear cell infiltrate and extravasated erythrocytes. However, deeper sections had necrotic keratinocytes and multinucleated epithelial-type giant cells with ground-glass nuclei restricted to the follicular epithelium, confirming a diagnosis of follicular herpetic infection (Fig 3, A and B). A diagnosis of HZ in the L4 and L5 dermatomes was made, and the eruption promptly resolved with a 7-day course of valganciclovir (1-g tablet 3 times a day)

    Resolution of urticarial vasculitis after treatment of neurocysticercosis

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    Urticarial vasculitis is most often idiopathic, but may occur in association with autoimmune disease, malignancy, drugs, or infection. Parasitic infection is a rare cause of urticarial vasculitis. We report a case of urticarial vasculitis that resolved after the diagnosis and treatment of neurocysticercosis

    Clinical, Radiological, and Pathological Diagnosis of Fibro-Osseous Lesions of the Oral and Maxillofacial Region: A Retrospective Study

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    BACKGROUND: Fibro-osseous lesions (FOL) of the jaw represent a rare, benign group of lesions that share similar clinical, radiological, and histopathological features and are characterized by progressive, variable replacement of healthy bone tissue by fibrous connective tissue. METHODS: This retrospective study aimed to evaluate the incidence of fibro-osseous lesions and to reassess the efficacy of case-specific treatment management from a clinical, radiological, and histopathological perspective based on 14 years of data. RESULTS: Forty-four patients with a radiological and/or histopathological diagnosis of benign FOLs were identified and re-evaluated. Cemento-osseous dysplasia was the most common group of FOLs present in our patient cohort (45%), followed by ossifying fibroma (39%) and fibrous dysplasia (16%). The diagnostic imaging technique of choice was CBCT (68%), followed by PAN (18%), with most patients (95 %) additionally undergoing biopsy. The mean age of the patients at the time of diagnosis was 40.54 ± 13.7 years, with most lesions being located in the mandible (86%), with females being predominantly affected (73%). CONCLUSION: An interdisciplinary approach that analyzes all case-specific factors, including demographic data, medical history, intraoperative findings, and, most importantly, histopathological and radiological features, is essential for an accurate diagnosis and key to avoiding inappropriate treatment

    Caribbean Corals in Crisis: Record Thermal Stress, Bleaching, and Mortality in 2005

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    BACKGROUND The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin. METHODOLOGY/PRINCIPAL FINDINGS Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles. CONCLUSIONS/SIGNIFICANCE Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate.This work was partially supported by salaries from the NOAA Coral Reef Conservation Program to the NOAA Coral Reef Conservation Program authors. NOAA provided funding to Caribbean ReefCheck investigators to undertake surveys of bleaching and mortality. Otherwise, no funding from outside authors' institutions was necessary for the undertaking of this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    The political, research, programmatic, and social responses to adolescent sexual and reproductive health and rights in the 25 years since the International Conference on Population and Development

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    Among the ground-breaking achievements of the International Conference on Population and Development (ICPD) was its call to place adolescent sexual and reproductive health (ASRH) on global health and development agendas. This article reviews progressmade in low- and middle-income countries in the 25 years since the ICPD in six areas central to ASRH-adolescent pregnancy, HIV, child marriage, violence against women and girls, female genital mutilation, and menstrual hygiene and health. It also examines the ICPD's contribution to the progress made. The article presents epidemiologic levels and trends; political, research, programmatic and social responses; and factors that helped or hindered progress. To do so, it draws on research evidence and programmatic experience and the expertise and experiences of a wide number of individuals, including youth leaders, in numerous countries and organizations. Overall, looking across the six health topics over a 25-year trajectory, there has been great progress at the global and regional levels in putting adolescent health, and especially adolescent sexual and reproductive health and rights, higher on the agenda, raising investment in this area, building the epidemiologic and evidence-base, and setting norms to guide investment and action. At the national level, too, there has been progress in formulating laws and policies, developing strategies and programs and executing them, and engaging communities and societies in moving the agenda forward. Still, progress has been uneven across issues and geography. Furthermore, it has raced ahead sometimes and has stalled at others. The ICPD's Plan of Action contributed to the progress made in ASRH not just because of its bold call in 1994 but also because it provided a springboard for advocacy, investment, action, and research that remains important to this day. (C) 2019 Published by Elsevier Inc. on behalf of Society for Adolescent Health and Medicine

    Genotypic diversity and phenotypic spectrum of infantile liver failure syndrome type 1 due to variants inLARS1

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    Purpose: Biallelic variants in LARS1, coding for the cytosolic leucyl-tRNA synthetase, cause infantile liver failure syndrome 1 (ILFS1). Since its description in 2012, there has been no systematic analysis of the clinical spectrum and genetic findings. Methods: Individuals with biallelic variants in LARS1 were included through an international, multicenter collaboration including novel and previously published patients. Clinical variables were analyzed and functional studies were performed in patient-derived fibroblasts. Results: Twenty-five individuals from 15 families were ascertained including 12 novel patients with eight previously unreported variants. The most prominent clinical findings are recurrent elevation of liver transaminases up to liver failure and encephalopathic episodes, both triggered by febrile illness. Magnetic resonance image (MRI) changes during an encephalopathic episode can be consistent with metabolic stroke. Furthermore, growth retardation, microcytic anemia, neurodevelopmental delay, muscular hypotonia, and infection-related seizures are prevalent. Aminoacylation activity is significantly decreased in all patient cells studied upon temperature elevation in vitro. Conclusion: ILFS1 is characterized by recurrent elevation of liver transaminases up to liver failure in conjunction with abnormalities of growth, blood, nervous system, and musculature. Encephalopathic episodes with seizures can occur independently from liver crises and may present with metabolic stroke

    Older women, breast cancer, and social support

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    One in ten women over the age of 65 will develop breast cancer. Despite this high incidence of breast cancer among older women, social support for them is often inadequate. This paper describes a qualitative study of the impact of a breast cancer diagnosis on older women from racially/ethnically diverse populations and their subsequent need for social support. Forty-seven older African American, Asian American, Caucasian and Latina women between the ages of 65 to 83 participated in a larger study examining the impact of breast cancer on women from racially/ethnically diverse populations and the meaning and nature of social support. The women completed an in-depth qualitative interview on the psychosocial impact of breast cancer and the meaning and nature of social support. The results indicate that there are variations in reactions to a breast cancer diagnosis among older women, and that these reactions impact their experiences with seeking social support at diagnosis and during treatment. Respondents were concerned about their aging bodies, potential dependency on others, and loss of autonomy. At the same time, the severity of cancer treatment and existing co-morbidities often meant they needed to learn to receive support, and to reach out if they had no support. The implications of these findings underscore the older cancer patient’s need to strengthen her supportive networks at the time of diagnosis, during treatment, and post-treatment
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