Whether seismic rupture propagates over large distances to generate mega-earthquakes or is rapidly aborted mainly depends on the slip processes within the fault core, including particularly frictional melting or intense grain-size reduction and amorphization. The record of seismic slip in exhumed fault zones consists in many instances in Black Faults Rocks, dark and glass-like-filled aphanitic veins that have been interpreted as resulting from the quenching of frictional melts, i.e.
View Article and Find Full Text PDFIn order to clarify the link between Ar/Ar record in white mica and deformation, we performed in situ and bulkwise Ar/Ar dating over the East Tenda Shear Zone (Tenda massif, Alpine Corsica). White micas from 11 samples were selected and extensively analyzed using in situ techniques across nested scales of strain-intensity gradients developed at the expense of a late-Variscan protolith. Ar/Ar systematics are unaffected by inherited Ar and directly linked to deformation with little or no Ar lattice (volume) diffusion.
View Article and Find Full Text PDFObjective: To determine physicians' knowledge of cardiopulmonary resuscitation (CPR) guidelines at the University Hospital of the West Indies (UHWI), Jamaica, and their current certification status in basic life support (BLS), advanced cardiac life support (ACLS), paediatric advanced life support (PALS) and advanced trauma life support (ATLS).
Methods: This was a cross-sectional study. A 23-item self-administered questionnaire was used to assess physicians practising at the UHWI, from the Departments of Anaesthesia, Surgery, Internal Medicine, Accident and Emergency, Obstetrics and Gynaecology and Oncology.
Background And Objectives: Emergence delirium is a distressing complication of the use of sevoflurane for general anesthesia. This study sought to determine the incidence of emergence delirium and risk factors in patients at a specialist pediatric hospital in Kingston, Jamaica.
Methods: This was a cross-sectional, observational study including pediatric patients aged 3-10 years, ASA I and II, undergoing general anesthesia with sevoflurane for elective day-case procedures.
Objectives: The aim of this survey was to establish the pain management approaches to acute painful crisis (APC) in sickle cell patients at two healthcare facilities and to compare with available guidelines.
Methods: A multi-centre observational survey of the management of APC in sickle cell patients was conducted. Data were collected at the Sickle Cell Unit (SCU), Tropical Medicine Research Institute (TMRI) and Accident and Emergency Department (A&E), University Hospital of the West Indies.
West Indian Med J
January 2014
Objective: Many neurosurgical cases are done without the need for blood transfusion, yet blood is unnecessarily cross-matched, resulting in wasted resources. This study was undertaken to document and compare the number of units of blood components requested, cross-matched and transfused in neurosurgical cases at the University Hospital of the West Indies (UHWI).
Methods: A prospective, observational study was undertaken over one year.
Objectives: To determine if a single preoperative dose of ketamine hydrochloride reduces the narcotic analgesic requirements and/or pain scores reported by patients in the first 24 hours postoperatively.
Methods: A single-centred, prospective, case-control study was conducted on 84 patients aged 18-65 years, American Society of Anaesthesiologists (ASA) I and II, undergoing elective gynaecological procedures at the University Hospital of the West Indies (UHWI). Patients were randomly assigned to one of two treatment groups: (a) ketamine group, where patients received intravenous ketamine 0.
Background And Objectives: Minor postoperative anesthetic complications may increase patient discomfort and dissatisfaction and delay recovery. This paper sought to determine the frequency of minor complications in the first 48 hours postoperatively reported by elective gynecological and orthopedic surgical patients at the University Hospital of the West Indies, Jamaica. Overall satisfaction with anesthetic care and possible risk factors for developing complications were also assessed.
View Article and Find Full Text PDFWest Indian Med J
November 2009
Objective: There is little information on adverse anaesthetic outcomes from the Caribbean. The aim of this study was to investigate the occurrence of anaesthetic morbidity and mortality at the University Hospital of the West Indies (UHWI) and to identify possible risk factors.
Methods: All anaesthetic procedures at the UHWI were monitored for adverse events and patient outcomes for the 12-month period from March 2004 to February 2005.
A cross-sectional, descriptive study utilizing data collected in the 'Trauma Registry' of the Department of Surgery, Radiology, Anaesthesia and Intensive Care at the University Hospital of the West Indies (UHWI) was undertaken to document injury severity, surgical requirements and intensive care needs of head-injured patients transferred to the UHWI over a three-year period Of 144 patients studied, the majority (71%) were young males. Overall, injury tended to be mild Twenty-three patients (16.0%) had severe head injury and 27 patients (18.
View Article and Find Full Text PDFThe worldwide scarcity of intensive care therapy leads to the rationing of this expensive resource. This prospective study investigates the rationing of intensive therapy at the University Hospital of the West Indies (UHWI) by recording triage decisions for intensive care unit (ICU) admission and the impact of these decisions on patient outcome. Between June 2001 and May 2002, all patients triaged for admission to a multidisciplinary ICU were studied For each patient, data were collected including APACHE II score, ICU resource availability and patient survival.
View Article and Find Full Text PDFAlthough adult neurogenesis has now been demonstrated in many different species, the functional role of newborn neurons still remains unclear. In the house cricket, a cluster of neuroblasts, located in the main associative center of the insect brain, keeps producing new interneurons throughout the animal's life. Here we address the functional significance of adult neurogenesis by specific suppression of neuroblast proliferation using gamma irradiation of the insect's head and by examining the impact on the insect's learning ability.
View Article and Find Full Text PDFAm J Physiol Renal Physiol
September 2003
Polyamines are involved in the control of the cell cycle and cell growth. In murine kidney, testosterone enhances gene expression of ornithine decarboxylase (ODC), the first enzyme in polyamine biosynthesis. In this study, we document the time course effect of testosterone on 1) gene expression of ODC, antizyme 1 (AZ1), and spermidine/spermine-N1-acetyltransferase (N1-SSAT); 2) ODC activity in proximal convoluted tubules (PCT) and cortical proximal straight tubules (CPST); and 3) renal polyamine levels.
View Article and Find Full Text PDFWe investigated the nitric oxide (NO) synthase and arginase pathways in resident peritoneal macrophages of mice infected with the tropical parasite Schistosoma mansoni. The two enzymes may have opposite effects, insofar as NO may be involved in the killing of the parasite whereas arginase may stimulate parasite growth via polyamine synthesis. We determined the effects of the infection on the expression and activity of the two enzymes in macrophages, before and after cytokine activation.
View Article and Find Full Text PDFFos-related antigens (Fra) were detected in the nuclei of neurones in young adult Acheta domesticus female crickets by immunohistochemical analysis, using an antibody that recognizes the amino-acid sequence 127-152 of c-Fos protein. Specificity of Fra immunoreactivity was confirmed by Western blot analysis of nuclear extracts from neural tissues. A major immunoreactive doublet with an apparent molecular mass of 52,000/54,000 Da was detected in nuclear extracts.
View Article and Find Full Text PDFWest Indian Med J
September 2000
Mushroom bodies are the main integrative structures of insect brain. They receive sensory information from the eyes, the palps, and the antennae. In the house cricket, Acheta domesticus, a cluster of mushroom body neuroblasts keeps producing new interneurons during an insect's life span.
View Article and Find Full Text PDFThe distribution of putative RDL-like GABA receptors and of gamma-aminobutyric acid (GABA) in the brain of the adult house cricket Acheta domesticus was studied using specific antisera. Special attention was given to brain structures known to be related to learning and memory. The main immunostaining for the RDL-like GABA receptor was observed in mushroom bodies, in particular the upper part of mushroom body peduncle and the two arms of the posterior calyx.
View Article and Find Full Text PDFPersistent neurogenesis in an adult insect brain was recently shown to be stimulated by juvenile hormone (JH). This morphogenetic hormone was also shown to act on polyamine biosynthesis. To analyze the possible involvement of polyamines in the neurogenic action of JH, two series of experiments were carried out with adult female crickets, Acheta domesticus: (i) inhibition of the first key enzyme in polyamine biosynthesis, ornithine decarboxylase, with alpha-difluoromethylornithine (alpha-DFMO), and examination of the effects of this treatment on the neuroblast proliferation response to JH; and (ii) examination of the effects of putrescine supplementation on the mitotic index of JH-deprived and alpha-DFMO-treated females.
View Article and Find Full Text PDFThe role of polyamines in the expression of cricket oviposition, a juvenile hormone-dependent behavior, was investigated using a specific inhibitor of ornithine decarboxylase, alpha-difluoromethylornithine (alpha-DFMO). The fat body of treated female house crickets (Acheta domesticus) did not show any putrescine and presented reduced levels of spermidine, whereas spermine titres were significantly enhanced. In nervous tissue, alpha-DFMO did not affect spermine titres but induced a severe drop in spermidine levels.
View Article and Find Full Text PDFThe occurrence of neurogenesis in mushroom bodies of adult insects belonging to several orthopteroid and coleopteran families is described. Using injections of 5-bromo, T2'-deoxyuridine, we showed that neuroblasts, which are progenitors of Kenyon cells during preimaginal instars, continue to divide in adult Acheta domesticus. Their progeny constitute a central column in mushroom body cortices of 3-week-old females.
View Article and Find Full Text PDFA study was performed on females Acheta domesticus to examine the effects of various experimental conditions on the ovarian physiology. Using a radioimmunoassay to determine juvenile hormone (JH) titers as well as in vitro JH biosynthesis, we observed that retention of mature follicles in egg-retaining females, i.e.
View Article and Find Full Text PDFJ Neurosci Methods
February 1986
Solid HRP pellets prepared with a 2.5% Triton X-100 aqueous solution were implanted either into corpora allata or applied onto neurohemal organs of a cricket. The method presents two advantages: it allows one to perform "in vivo" instead of "in vitro" experiments, and detergent HRP pellets are easy to manipulate.
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