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Background: Self-harm (any self-injury or -poisoning regardless of intent) is highly prevalent in transgender and gender diverse (TGD) populations. It is strongly associated with various adverse health and wellbeing outcomes, including suicide. Despite increased risk, TGD individuals' unique self-harm pathways are not well understood. Following PRISMA guidelines we conducted the first systematic review of risk and protective factors for self-harm in TGD people to identify targets for prevention and intervention. Methods: We searched five electronic databases (PubMed, PsychInfo, Scopus, MEDLINE, and Web of Science) published from database inception to November 2023 for primary and secondary studies of risk and/or protective factors for self-harm thoughts and behaviours in TGD people. Data was extracted and study quality assessed using Newcastle-Ottawa Scales. Findings: Overall, 78 studies published between 2007 and 2023 from 16 countries (N = 322,144) were eligible for inclusion. Narrative analysis identified six key risk factors for self-harm in TGD people (aged 7-98years) were identified. These are younger age, being assigned female at birth, illicit drug and alcohol use, sexual and physical assault, gender minority stressors (especially discrimination and victimisation), and depression or depressive symptomology. Three important protective factors were identified: social support, connectedness, and school safety. Other possible unique TGD protective factors against self-harm included: chosen name use, gender-identity concordant documentation, and protective state policies. Some evidence of publication bias regarding sample size, non-responders, and confounding variables was identified. Interpretation: This systematic review indicates TGD people may experience a unique self-harm pathway. Importantly, the risk and protective factors we identified provide meaningful targets for intervention. TGD youth and those assigned female at birth are at increased risk. Encouraging TGD people to utilise and foster existing support networks, family/parent and peer support groups, and creating safe, supportive school environments may be critical for self-harm and suicide prevention strategies. Efforts to reduce drug and alcohol use and experiences of gender-based victimisation and discrimination are recommended to reduce self-harm in this high-risk group. Addressing depressive symptoms may reduce gender dysphoria and self-harm. The new evidence presented in this systematic review also indicates TGD people may experience unique pathways to self-harm related to the lack of social acceptance of their gender identity. However, robust longitudinal research which examines gender-specific factors is now necessary to establish this pathway.
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PURPOSE: The purpose of this study was to explore the immediate effects of heavy isometric plantar flexor exercise on sensory output (pain during a functional task and mechanical pain sensitivity) and motor output (plantar flexor torque) in individuals with Achilles tendinopathy. METHODS: Sixteen subjects with Achilles tendinopathy participated in the study, mean (SD) age 48.6 (8.9) years and Victorian institute assessment-Achilles (VISA-A) score 61.3 (23.0). Sensory testing assessing pain during a functional task, mechanical pain sensitivity and motor output, and plantar flexor peak torque was completed prior to the intervention. All subjects completed a 45-s heavy isometric plantar flexor contraction and were then re-tested using the same sensory and motor tests. Motor output was assessed using isokinetic dynamometry at speeds previously identified as of interest in subjects with Achilles tendinopathy. RESULTS: Only 9 of the 16 subjects experienced pain during a functional task, self-reported pain was 4.2 (1.9) numerical rating scale (NRS) pre-intervention and 4.9 (3.2) NRS postintervention (n.s.). Mechanical pressure sensitivity was 446.5 (± 248.5) g/mm2 pre-intervention and 411.8 (± 211.8) g/mm2 post-intervention (n.s.). Mean concentric plantar flexor torque at 90 and 225°/s was 47.1 (14.5) and 33.6 (11.6) Nm, respectively, pre-intervention and 53.0 (18.5) and 33.4 (6.6) Nm post-intervention (p = 0.039 and n.s.). Eccentric torque at 90°/s was 98.5 (34.2) Nm preintervention versus 106.0 (41.4) Nm post-intervention (n.s.). CONCLUSION: In this exploratory study, patients with Achilles tendinopathy had a varied sensory and motor output response to heavy isometric contractions. Using the recommended approach of heavy 45-s isometric contractions did not offer a meaningful acute benefit for sensory or motor output for subjects with Achilles tendinopathy. Based on this study, heavy 45-s isometric contractions cannot be recommended for immediate pain relief or improved motor output for patients with Achilles tendinopathy. LEVEL OF EVIDENCE: IV, prospective cohort study.
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Tendón Calcáneo/fisiopatología , Terapia por Ejercicio/métodos , Contracción Isométrica , Dolor/fisiopatología , Tendinopatía/fisiopatología , Tendinopatía/terapia , Adulto , Anciano , Estudios de Cohortes , Femenino , Pie/fisiología , Humanos , Masculino , Persona de Mediana Edad , Manejo del Dolor , Dimensión del Dolor , Modalidades de Fisioterapia , Estudios Prospectivos , Autoinforme , Encuestas y Cuestionarios , TorqueRESUMEN
This paper describes high-resolution in situ observations of temperature and, for the first time, of salinity in the uppermost skin layer of the ocean, including the influence of large surface blooms of cyanobacteria on those skin properties. In the presence of the blooms, large anomalies of skin temperature and salinity of 0.95°C and -0.49 practical salinity unit were found, but a substantially cooler (-0.22°C) and saltier skin layer (0.19 practical salinity unit) was found in the absence of surface blooms. The results suggest that biologically controlled warming and inhibition of salinization of the ocean's surface occur. Less saline skin layers form during precipitation, but our observations also show that surface blooms of Trichodesmium sp. inhibit evaporation decreasing the salinity at the ocean's surface. This study has important implications in the assessment of precipitation over the ocean using remotely sensed salinity, but also for a better understanding of heat exchange and the hydrologic cycle on a regional scale.
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A 2-year-old girl presented to the emergency department at 3:00 h with severe pain in her right eye and a rust coloured, blood stained frothy discharge that had woken her. An examination of her eye revealed a shiny metallic looking foreign body, which was immediately removed by the on-call ophthalmologist. That morning the patient underwent ocular examination under anaesthesia and was found to have severe tissue necrosis resulting from an electrochemical burn. She was treated with daily rodding for 3 days and betamethasone ointment four times a day, which was gradually tapered. At 3 months her only eye pathology was a mild symblepharon between the bulbar and tarsal conjunctiva. This is the first case of delayed symptoms after placement of a button battery into the conjunctival fornix. This case highlights the serious nature of button battery injuries to the eye and the potential to miss the diagnosis owing to a delayed onset of symptoms.
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Quemaduras Químicas , Conjuntiva/patología , Enfermedades de la Conjuntiva , Suministros de Energía Eléctrica , Lesiones Oculares , Cuerpos Extraños , Betametasona/uso terapéutico , Quemaduras Químicas/diagnóstico , Quemaduras Químicas/tratamiento farmacológico , Quemaduras Químicas/etiología , Preescolar , Enfermedades de la Conjuntiva/diagnóstico , Enfermedades de la Conjuntiva/tratamiento farmacológico , Enfermedades de la Conjuntiva/etiología , Lesiones Oculares/diagnóstico , Lesiones Oculares/tratamiento farmacológico , Lesiones Oculares/etiología , Femenino , HumanosRESUMEN
WHAT IS KNOWN AND OBJECTIVE: It is known that adverse drug reactions (ADRs) cause admission to hospital in adults and children. A recent adult study showed that ADRs are an important and frequent cause of hospital admission. The objective of this study is to develop methodology to ascertain the current burden of ADRs through a prospective analysis of all unplanned admissions to a paediatric hospital. METHODS: Prospective observational study over a 2-week period. RESULTS AND DISCUSSION: There were 19 admissions to the main hospital wards related to an ADR, giving an estimated incidence of 4%, with the ADR directly leading to the admission in 71% of cases. There were no deaths attributable to ADR. 33% of the reactions were possibly avoidable. The drugs most commonly implicated in causing admissions were anti-neoplastic agents. The most common reactions were neutropenia, vomiting and diarrhoea. The health burden of ADRs in the paediatric population is likely to be significant. This pilot study will be used to inform a much larger prospective study providing more detailed evidence of the burden of ill-health from ADRs in children. This larger study will add to a body of research aiming to identify drug-related problems within children to aid paediatric pharmacovigilance. WHAT IS NEW AND CONCLUSION: This study provides knowledge regarding the methodology to be used for a larger study investigating ADRs in children. The study will allow authors who wish to replicate the study in their own populations (internationally) to avoid some of the pitfalls in planning a large epidemiological study of paediatric ADRs. The study also provides an estimate of the incidence and problem of admissions caused by ADRs in a UK paediatric population.
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Sistemas de Registro de Reacción Adversa a Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Hospitalización , Hospitales Pediátricos , Niño , Bases de Datos Factuales , Departamentos de Hospitales , Humanos , Incidencia , Proyectos Piloto , Estudios Prospectivos , Reino UnidoRESUMEN
We previously developed an immunohistochemical method for estimating cell cycle state and phase in tissue samples, including biopsies that are too small for flow cytometry. We have used our technique to examine whether primary abnormalities of the cell cycle exist in laryngeal neoplasia. Antibodies against the markers of cell cycle entry, minichromosome maintenance protein-2 (Mcm-2) and Ki67, and putative markers of cell cycle phase, cyclin D1 (G1-phase), cyclin A (S-phase), cyclin B1 (G2-phase) and phosphohistone H3 (Mitosis) were applied to paraffin-embedded sections of normal larynx (n = 8), laryngeal dysplasia (n = 10) and laryngeal squamous cell carcinoma (n = 10). Cells expressing each marker were determined as a percentage of total cells, termed the labelling index (LI), and as a percentage of Mcm-2-positive cells, termed the labelling fraction (LF). The frequency of coexpression of each putative phase marker was investigated by confocal microscopy. There was a correlation between Mcm-2 and Ki67 LIs (rho = 0.93) but Mcm-2 LIs were consistently higher. All cells expressing a phase marker coexpressed Mcm-2, whereas Ki67 was not expressed in a proportion of these cells. The putative phase markers showed little coexpression. Labelling index values increased on progression from normal larynx through laryngeal dysplasia to squamous cell carcinoma for Mcm-2 (P = 0.001), Ki67 (P = 0.0002), cyclin D1 (P = 0.015), cyclin A (P = 0.0001) and cyclin B1 (P = 0.0004). There was no evidence of an increase in the LF for any phase marker. Immunohistochemistry can be used to estimate cell cycle state and phase in laryngeal biopsies. Our data argues against primary cell cycle phase abnormalities in laryngeal neoplasia.
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Carcinoma de Células Escamosas/patología , Neoplasias Laríngeas/patología , Biomarcadores de Tumor/biosíntesis , Ciclo Celular , Proteínas de Ciclo Celular/biosíntesis , Fase G1 , Fase G2 , Humanos , Inmunohistoquímica , Antígeno Ki-67/biosíntesis , Microscopía Confocal/métodos , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Mitosis , Proteínas Nucleares/biosíntesis , Adhesión en Parafina , Fase S , Sensibilidad y EspecificidadRESUMEN
Heparin was modified with adipic dihydrazide and covalently linked to surface-activated silica wafers. X-ray photoelectron spectroscopy was used at each stage of derivatization and showed that successful immobilization had taken place. Surfaces were imaged with atomic force microscopy to determine the uniformity of the heparin layer as well as its thickness. In situ ellipsometry was used to estimate layer thickness as well, and to study protein concentration and adsorption time effects on the adsorption and elution kinetics exhibited by human plasma fibrinogen. The adsorbed amount of fibrinogen increased with time and concentration on each type of surface. Under all experimental conditions, fibrinogen adsorbed at a lower rate and to a lower extent on heparinized as compared to unheparinized silica. In addition, buffer elution experiments showed that fibrinogen was less tightly bound to heparinized silica. In order to examine behavior relative to fibrinogen mobility at these interfaces, the sequential adsorption of fibrinogen was recorded. The difference in adsorption rates between the first and second adsorption cycles, evaluated at identical mass density, indicated that post-adsorptive molecular rearrangements had taken place. In general, higher solution concentration and longer adsorption time in the first adsorption step led to more rearrangement, and these history dependent effects were more pronounced on the heparinized silica. These rearrangements are suggested to involve clustering of adsorbed fibrinogen, in this way increasing the amount of unoccupied area at the interface. These rearrangements were presumably facilitated on the heparinized silica by enhanced lateral mobility of fibrinogen at this negatively charged, highly hydrophilic interface.
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Adipatos/química , Anticoagulantes/química , Fibrinógeno/química , Heparina/química , Dióxido de Silicio/química , Adipatos/metabolismo , Adsorción , Anticoagulantes/metabolismo , Secuencia de Carbohidratos , Heparina/metabolismo , Cinética , Microscopía de Fuerza Atómica , Datos de Secuencia Molecular , Propiedades de Superficie , Factores de TiempoRESUMEN
We have investigated whether immunohistochemical markers can identify differences in cell cycle phase distribution in ovarian serous neoplasms, including borderline tumours of different grades. Sections of normal ovary (n=18), serous cystadenoma (n=21), borderline serous tumours (n=21) and serous cystadenocarcinoma (n=15) were analysed by immunohistochemistry using markers of cell cycle entry (Mcm-2) and cell cycle phase, including cyclin D1 (mid-to-late G1), cyclin A (S phase), cyclin B1 (G2 phase) and phosphohistone H3 (mitosis). Double-labelling confocal microscopy confirmed marker phase specificity and phase estimations were corroborated by flow cytometry. On progression from normal ovary through serous cystadenoma and borderline tumours to cystadenocarcinomas, expression of Mcm-2 (P<0.0001), cyclin D1 (P=0.002), cyclin A (P<0.0001), cyclin B1 (P<0.0001) and phosphohistone H3 (P<0.0001) increased, paralleled by an increase in the S-phase fraction (cyclin A : Mcm-2 ratio; P=0.002). Borderline tumours of increasing grade also showed increased Mcm-2 and cyclin A expression, together with an increase in the S-phase fraction. Immunohistochemistry can be used to estimate cell cycle phase distribution in ovarian serous neoplasms, giving results similar to flow cytometric analysis and enabling direct assessment of tumour heterogeneity. Immunohistochemical estimates of the S-phase fraction may identify serous borderline tumours likely to exhibit malignant progression and/or select serous cystadenocarcinomas likely to respond to adjuvant therapy.
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Biomarcadores de Tumor/análisis , Proteínas de Ciclo Celular/análisis , Ciclo Celular , Cistadenocarcinoma Seroso/patología , Neoplasias Ováricas/patología , Proteínas de Ciclo Celular/biosíntesis , Transformación Celular Neoplásica , Progresión de la Enfermedad , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica/métodos , Microscopía Confocal , Lesiones Precancerosas , Manejo de EspecímenesRESUMEN
OBJECTIVE: Minichromosome maintenance protein 2 (Mcm2) is an accurate indicator of cell cycle entry in tissue samples, but its expression in inflammatory bowel disease (IBD) has not previously been investigated. We have used immunohistochemistry to assess the expression of Mcm2, in comparison to the existing proliferation marker Ki-67, in active IBD and IBD without inflammatory activity. MATERIALS AND METHODS: For this experimental study, sections from colonic biopsy and resection specimens of 48 patients with IBD (5 inactive/quiescent Crohn's disease (CD), 13 active CD, 19 inactive/quiescent ulcerative colitis (UC) and 11 active UC) and 15 normal controls were immunostained with antibodies to Mcm2 and Ki-67. The percentage of immunopositive epithelial nuclei was determined by calculating a labelling index (LI) for entire glands and for gland thirds (superficial, middle and basal). RESULTS: The Mcm2 LI was significantly increased in the superficial third of glands in active vs. inactive/quiescent UC (P < 0.0001) and active vs. inactive/quiescent CD (P = 0.001). The Mcm2 LI was significantly greater than the Ki-67 LI in active IBD, both in entire glands (P < 0.0001) and in the superficial third of glands (UC, P = 0.001; CD, P = 0.0002). Mcm2 LIs for entire glands were significantly higher in UC (all cases) compared to CD (all cases) (P = 0.032). CONCLUSIONS: There is increased cell cycle entry, as indicated by expression of Mcm2 and to a lesser extent Ki-67, in the superficial third of colonic glands in active IBD compared to inactive/quiescent IBD. Detection of Mcm2 may contribute to improved histological assessment of small tissue biopsies and may enable the development of a direct stool-based test for detection of active IBD and potentially for assessment of disease activity.
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Proteínas de Ciclo Celular/biosíntesis , Colon/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Mucosa Intestinal/metabolismo , Colitis Ulcerosa/metabolismo , Enfermedad de Crohn/metabolismo , Humanos , Antígeno Ki-67/biosíntesisRESUMEN
Histological classification of laryngeal epithelial lesions is highly subjective, and methods of cytological detection are not well developed. Improved determination of aberrant cell cycle entry may allow increased objectivity in histological assessment and enable the development of less invasive diagnostic cytology tests. Sections of normal larynx (n=10), laryngeal dysplasia (n=20) and laryngeal squamous cell carcinoma (SCC) (n=10) were classified according to the Ljubljana classification and stained for markers of cell cycle entry, minichromosome maintenance protein-2 (Mcm-2) and Ki67. Expression patterns were compared using double labelling confocal microscopy. There was a correlation between Mcm-2 and Ki67 labelling indices (rho=0.93; 95% CI [0.84, 0.97]) and both markers showed increased expression from normal epithelium to SCC (Mcm-2, P=0.001; Ki67, P=0.0002). Importantly, there was minimal expression of Mcm-2 or Ki67 in the most superficial layers of normal larynx and abnormal or atypical hyperplasia, in contrast to carcinoma in situ and SCC. Clusters of Mcm-2/5-positive cells were present in cytological preparations from SCC, but not from those showing atypical hyperplasia or inflammation in non-neoplastic tissue. Minichromosome maintenance protein-2 staining may increase the objectivity and reliability of histological grading of laryngeal epithelial lesions. Laryngeal brushings, combined with immuno-enhanced liquid-based cytology, could be useful, as a less invasive approach, to the detection of laryngeal malignant and premalignant lesions.
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Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Antígeno Ki-67/metabolismo , Neoplasias Laríngeas/metabolismo , Proteínas Nucleares/metabolismo , Antígenos de Neoplasias/metabolismo , Biopsia , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Carcinoma de Células Escamosas/patología , Ciclo Celular , Replicación del ADN , Humanos , Hiperplasia/metabolismo , Hiperplasia/patología , Técnicas para Inmunoenzimas , Neoplasias Laríngeas/patología , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patologíaRESUMEN
Vulval intraepithelial neoplasia (VIN) is defined histopathologically by distinctive abnormalities of cellular maturation and differentiation. To investigate the functional properties of VIN, the expression of several proteins involved in the regulation of the cell cycle as well as in situ DNA replication competence was analysed by immunohistochemistry. Snap-frozen vulval biopsies were graded as normal squamous epithelium (n=6), undifferentiated HPV positive VIN 1 (n=3), VIN 2 (n=8) and VIN 3 (n=20). Immunohistochemistry was performed using the following markers: cyclin D1 (expressed in middle/late G1), cyclin B1 (expressed in G2/early M), phosphorylated histone H3 (expressed during mitosis) and minichromosome maintenance (Mcm) proteins 2 and 5 (expressed during the cell cycle, but not in differentiated or quiescent cells). In situ DNA replication competence was used to identify S-phase cells. The percentage of positively stained nuclei in three representative microscopic fields was calculated per biopsy. In normal vulva, the expression of all markers was restricted to the proliferative compartment of the basal layer of the epithelium. In contrast in high-grade VIN, the majority of epithelial cells expressed the Mcm proteins from basal to superficial layer. The detection of cyclins B1 and D1, phospho-histone H3 and in situ DNA replication was also found through the full thickness of these lesions but by a lower proportion of the cells. This is consistent with these markers providing a series of 'snapshots' of the cell cycle status of individual cells. The low-grade VIN showed reduced expression of the cell cycle markers in relation to the level of dysplasia. The combination of these analyses establishes that the majority of VIN cells remain in a functional replicative or prereplicative state of the cell cycle. Clinical application of these analyses may provide a basis for improved diagnosis of VIN.
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Biomarcadores de Tumor/metabolismo , Carcinoma in Situ/genética , Carcinoma in Situ/metabolismo , Replicación del ADN , ADN de Neoplasias/metabolismo , Neoplasias de la Vulva/genética , Neoplasias de la Vulva/metabolismo , Biopsia , Carcinoma in Situ/patología , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Ciclina B/metabolismo , Ciclina B1 , Ciclina D1/genética , Ciclina D1/metabolismo , Proteínas de Unión al ADN , Femenino , Histonas/genética , Humanos , Técnicas para Inmunoenzimas , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Proteínas Nucleares/metabolismo , Proteínas de Schizosaccharomyces pombe , Neoplasias de la Vulva/patologíaRESUMEN
We have investigated the potential utility of monoclonal antibodies against mini-chromosome maintenance-2 protein (Mcm2) in predicting meningioma recurrence. MCM proteins are members of the DNA-binding prereplicative complex and are essential for eukaryotic DNA replication. They are present throughout the cell cycle, but are down-regulated in quiescence and cell differentiation, making them specific markers of proliferating cells. We analysed 10 benign meningiomas that subsequently recurred within a 5-year period, together with 20 matched non-recurrent benign meningiomas. There was no significant correlation between histological subtype, mitotic count or Ki-67 labelling index and tumour recurrence. We observed that whilst the average Mcm2 labelling index (LI) of the tumour section as a whole (LI(Ave)) is not significantly different between recurrent and nonrecurrent meningiomas, the Mcm2 labelling index in the area of highest proliferative activity within the tumour section (LI(Max)) is significantly higher in recurrent meningiomas (p < 0.0001). Seven out of the 10 recurrent meningiomas displayed a Mcm2 LI((Max) greater than 30%, compared to 0 out of 20 for non-recurrent tumours. In conclusion, these results suggest that analysis of Mcm2 expression may facilitate identification of patients with a high risk of meningioma recurrence, for whom adjuvant radiotherapy may be of benefit.
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Biomarcadores de Tumor/análisis , Meningioma/química , Proteínas de Neoplasias/análisis , Recurrencia Local de Neoplasia/química , Proteínas Nucleares/análisis , Adulto , Anciano , Anticuerpos Monoclonales/inmunología , Replicación del ADN , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Masculino , Meningioma/patología , Persona de Mediana Edad , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Índice Mitótico , Recurrencia Local de Neoplasia/patología , Proteínas Nucleares/inmunología , PronósticoRESUMEN
OBJECTIVE: To evaluate plasma taurine concentrations (PTC), whole blood taurine concentrations (WBTC), and echocardiographic findings in dogs fed 1 of 3 protein-restricted diets that varied in fat and L-carnitine content. ANIMALS: 17 healthy Beagles. DESIGN: Baseline PTC and WBTC were determined, and echocardiography was performed in all dogs consuming a maintenance diet. Dogs were then fed 1 of 3 protein-restricted diets for 48 months: a low-fat (LF) diet, a high-fat and L-carnitine supplemented (HF + C) diet, or a high-fat (HF) diet. All diets contained methionine and cystine concentrations at or above recommended Association of American Feed Control Officials (AAFCO) minimum requirements. Echocardiographic findings, PTC, and WBTC were evaluated every 6 months. RESULTS: The PTC and WBTC were not significantly different among the 3 groups after 12 months. All groups had significant decreases in WBTC from baseline concentrations, and the HF group also had a significant decrease in PTC. One dog with PT and WBT deficiency developed dilated cardiomyopathy (DCM). Taurine supplementation resulted in significant improvement in cardiac function. Another dog with decreased WBTC developed changes compatible with early DCM. CONCLUSIONS AND CLINICAL RELEVANCE: Results revealed that dogs fed protein-restricted diets can develop decreased taurine concentrations; therefore, protein-restricted diets should be supplemented with taurine. Dietary methionine and cystine concentrations at or above AAFCO recommended minimum requirements did not prevent decreased taurine concentrations. The possibility exists that AAFCO recommended minimum requirements are not adequate for dogs consuming protein-restricted diets. Our results also revealed that, similar to cats, dogs can develop DCM secondary to taurine deficiency, and taurine supplementation can result in substantial improvement in cardiac function.
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Carnitina/farmacología , Dieta con Restricción de Proteínas/veterinaria , Grasas de la Dieta/farmacología , Perros/sangre , Corazón/efectos de los fármacos , Taurina/sangre , Animales , Biopsia/veterinaria , Carnitina/sangre , Carnitina/metabolismo , Dieta con Restricción de Proteínas/efectos adversos , Grasas de la Dieta/metabolismo , Perros/fisiología , Ecocardiografía/efectos de los fármacos , Electrocardiografía/veterinaria , Femenino , Corazón/fisiología , Masculino , Distribución Aleatoria , Análisis de Regresión , Taurina/biosíntesisRESUMEN
Five client owned dogs with cystinuria were diagnosed with carnitine and taurine deficiency while participating in a clinical trial that used dietary management of their urolithiasis. Stored 24-hour urine samples collected from the cystinuric dogs before enrollment in the clinical diet trial were quantitatively evaluated for carnitine and taurine. These results were compared to those obtained from 18 healthy Beagles. Both groups of dogs were fed the same maintenance diet for a minimum of 2 weeks before 24-hour urine collection. The protocol used for 24-hour urine collections was the same for cystinuric dogs and healthy Beagles except that cystinuric dogs were catheterized at baseline, 8 hours, 12 hours, and at the end of the collection, whereas Beagles were catheterized at baseline, 8 hours, and at the end of the collection. Three of 5 dogs with cystinuria had increased renal excretion of carnitine. None of the cystinuric dogs had increased renal excretion of taurine, but cystinuric dogs excreted significantly less (P < .05) taurine in their urine than the healthy Beagles. Carnitinuria has not been recognized previously in either humans or dogs with cystinuria, and it may be 1 risk factor for developing carnitine deficiency. Cystinuric dogs in this study were not taurinuric; however, cystine is a precursor amino acid for taurine synthesis. Therefore, cystinuria may be 1 risk factor for developing taurine deficiency in dogs. We suggest that dogs with cystinuria be monitored for carnitine and taurine deficiency or supplemented with carnitine and taurine.
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Carnitina/deficiencia , Carnitina/orina , Cistinuria/veterinaria , Enfermedades de los Perros/orina , Taurina/deficiencia , Taurina/orina , Animales , Estudios de Casos y Controles , Cistinuria/orina , Perros , Femenino , MasculinoRESUMEN
Skeletal muscle samples from 38 draft horse-related animals 1-23 years of age were evaluated for evidence of aggregates of glycogen and complex polysaccharide characteristic of equine polysaccharide storage myopathy (EPSSM). Cardiac muscle from 12 of these horses was also examined. Antemortem serum levels of creatine kinase (CK) and aspartate aminotransferase (AST) from 9 horses with EPSSM and 5 horses without EPSSM were compared. Skeletal muscle from 17 horses contained inclusions of periodic acid-Schiff (PAS)-positive, amylase-resistant complex polysaccharide. Similar inclusions were also present in the cardiac muscle of 1 horse. A vacuolar myopathy with aggregates of PAS-positive, amylase-sensitive glycogen was seen in 8 other horses, and these findings are also considered diagnostic for EPSSM. Antemortem serum activities of CK and AST were often higher in EPSSM horses than in horses without EPSSM. Using the presence of amylase-resistant complex polysaccharide as the criterion for diagnosis of EPSSM, the incidence in this population was 45%. Inclusion of horses with aggregates of glycogen but no amylase-resistant complex polysaccharide as representative of the range of pathologic findings in horses with EPSSM resulted in a 66% incidence in this population.
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Errores Innatos del Metabolismo de los Carbohidratos/veterinaria , Metabolismo de los Hidratos de Carbono , Enfermedades de los Caballos/patología , Músculo Esquelético/patología , Amilasas/análisis , Amilasas/metabolismo , Animales , Autopsia/veterinaria , Errores Innatos del Metabolismo de los Carbohidratos/epidemiología , Errores Innatos del Metabolismo de los Carbohidratos/patología , Femenino , Glucógeno/análisis , Glucógeno/metabolismo , Caballos , Incidencia , Masculino , Enfermedades MuscularesRESUMEN
PURPOSE: Heparin binds to human platelets and can cause activation and aggregation, although the mechanisms are unknown. To determine how heparin alters platelet function, we identified platelet-binding sites for heparin and measured heparin's influence on the function of platelet integrin alpha(IIb)beta(3) (glycoprotein IIb/IIIa). METHODS: Photoaffinity cross-linking and affinity chromatography experiments were performed to identify platelet membrane proteins that bind heparin. Heparin's effect on fibrinogen binding to platelets was measured with a radioligand-binding assay. The translocation to the cytoskeleton of Rap2, a guanosine triphosphate-binding protein, was measured from platelets aggregating in response to heparin and other agonists. RESULTS: Cross-linking and affinity chromatographic experiments positively identified the integrin alpha(IIb)beta(3) as a heparin-binding site. Heparin aggregation was calcium dependent. Low concentrations of unfractionated porcine mucosal heparin (2-5 U/mL) significantly increased fibrinogen I 125 binding to activated platelets, whereas higher doses did not. Heparin-mediated platelet aggregation was completely blocked by GRGDS peptide (5 mmol/L), a competitive inhibitor of fibrinogen binding, and was blocked by EDTA (2 mmol/L), which dissociates the functional integrin complex. Aggregation was associated with Rap2 translocation to the cytoskeleton, a sign of outside-in signaling. CONCLUSIONS: Heparin binds to the alpha(IIb)beta(3) integrin in vitro and ex vivo, and heparin increases fibrinogen binding to the integrin. Heparin-mediated aggregation requires an intact integrin and ligand and leads to Rap2 translocation to the cytoskeleton-an outside-in signal of ligand engagement. Heparin may directly modulate platelet integrin function, most likely through direct binding and modulation of integrin function.
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Plaquetas/efectos de los fármacos , Heparina/farmacología , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Sitios de Unión , Células Cultivadas , Fibrinógeno/metabolismo , Humanos , Receptores de Superficie Celular/metabolismoRESUMEN
Turnover of carnitine in the body is primarily the result of renal excretion, and high-fat (HF) diets have been shown to increase urine carnitine excretion in healthy people. Recently, increased renal excretion of carnitine was observed in dogs diagnosed with cystinuria and carnitine deficiency. Carnitine deficiency has been linked to dilated cardiomyopathy and lipid storage myopathies in dogs and humans, and low-fat (LF) diets have been beneficial in some human patients with carnitine deficiency. In addition, HF, protein-restricted diets are often recommended for management of cystinuria in dogs. However, whether HF diets increase renal carnitine excretion in dogs or whether dogs with carnitine deficiency would benefit from LF diets remains unknown. Therefore, the purpose of this study was to determine the influence of dietary fat and carnitine on renal carnitine excretion in healthy dogs. Results from this study revealed that an HF diet increased urine carnitine excretion in dogs; however, carnitine excretion with the HF diet was not significantly different from that in dogs consuming an LF diet. Nonetheless, these results raise the possibility that increased renal carnitine excretion associated with HF diets could be one risk factor for development of carnitine deficiency in dogs with an underlying disorder in carnitine metabolism, and some dogs with carnitine deficiency may benefit from an LF diet. Another important observation in this study was that renal excretion of carnitine exceeded dietary intake in all diet groups, confirming previous reports that concluded that canine renal tubular cells reabsorb carnitine poorly when compared with those of humans.
Asunto(s)
Carnitina/farmacología , Carnitina/orina , Dieta/veterinaria , Grasas de la Dieta/farmacología , Perros/orina , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Carnitina/administración & dosificación , Grasas de la Dieta/administración & dosificación , Quimioterapia Combinada , Femenino , MasculinoRESUMEN
Path analysis was used to examine the antecedents of posttraumatic stress (PTS) symptoms in Tamil asylum-seekers, refugees, and immigrants in Australia. The Harvard Trauma Questionnaire and a postmigration living difficulties questionnaire were completed by 62 asylum-seekers, 30 refugees, and 104 immigrants who responded to a mail-out. Demographic characteristics, residency status, and measures of trauma and postmigration stress were fitted to a structural model in PTS symptoms. Premigration trauma exposure accounted for 20% of the variance of PTS symptoms. Postmigration stress contributed 14% of the variance. Although limited by sampling constraints and retrospective measurement, the study supports the notion that both traumatic and posttraumatic events contribute to the expression of PTS symptoms.
Asunto(s)
Emigración e Inmigración , Refugiados/psicología , Trastornos por Estrés Postraumático/etnología , Trastornos por Estrés Postraumático/psicología , Guerra , Adulto , Análisis de Varianza , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Gales del Sur , Análisis de Regresión , Características de la Residencia/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Sri Lanka/etnología , Trastornos por Estrés Postraumático/diagnóstico , Encuestas y CuestionariosRESUMEN
A new hetero-bifunctional photo crosslinking reagent, 2-(4-azidoanilyl)-4-(4-azabicyclo-[2,2, 2]hexylammonio)-6-morpholino-1,3,5-triazine chloride, was designed to detect and isolate heparin-binding protein(s) that may act as heparin-receptor(s) on the platelet surface. In a preliminary study using ethanol as a model substrate, the reagent was shown to react with the alcoholic hydroxy group under mild conditions and its crosslinking photoreactivity was high. The reagent effectively formed similar covalent bonds with heparin, while preserving its anticoagulant anti-Xa activity. [3H]Heparin labeled with this reagent crosslinked to antithrombin III very specifically but not to ovalbumin, as analyzed by the Bio-imaging Analyzer System (BAS, Fuji Photo Film, Tokyo). Affinity crosslinking of [3H]heparin was then used to detect heparin-binding proteins on the surface of intact platelets. Several discrete protein bands were detected by the BAS-imaging of SDS-PAGE.
Asunto(s)
Plaquetas/química , Proteínas Sanguíneas/aislamiento & purificación , Proteínas Portadoras/aislamiento & purificación , Reactivos de Enlaces Cruzados , Proteínas de la Membrana/aislamiento & purificación , Alcoholes , Antitrombina III , Plaquetas/metabolismo , Proteínas Sanguíneas/metabolismo , Proteínas Portadoras/sangre , Reactivos de Enlaces Cruzados/síntesis química , Heparina/metabolismo , Humanos , Técnicas In Vitro , Proteínas de la Membrana/sangre , Morfolinas/síntesis química , OvalbúminaRESUMEN
OBJECTIVE: To evaluate the reliability of taurine concentrations measured in a single urine sample obtained from dogs 8 hours after eating, compared with taurine concentrations measured in 24-hour urine samples. ANIMALS: 18 healthy Beagles. PROCEDURE: After emptying the urinary bladder by transurethral catheterization, dogs were fed a canned maintenance diet. Approximately 8 hours later, urine, plasma, and serum samples were obtained for determination of fractional urinary excretion of taurine and urine taurine-to-creatinine concentration ratios (Utaur:Ucr). Results were compared with 24-hour urinary taurine excretion rate. RESULTS: Unbound and total fractional urinary taurine excretion correlated well with unbound and total 24-hour urinary taurine excretion. However, bound fractional urinary taurine excretion correlated poorly with bound 24-hour urinary taurine excretion. Unbound and total Utaur:Ucr correlated well with unbound and total 24-hour urinary taurine excretion. However, bound Utaur:Ucr correlated poorly with bound 24-hour urinary taurine excretion. CONCLUSION AND CLINICAL RELEVANCE: Fractional urinary excretion of unbound and total taurine, and unbound and total Utaur:Ucr are reliable indicators of 24-hour urinary unbound and total taurine excretion in healthy dogs. However, determination of 24-hour urinary taurine excretion is recommended for evaluating urinary bound taurine concentrations of dogs.