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1.
Inj Prev ; 25(5): 414-420, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-29778992

RESUMEN

PURPOSE: To determine the impact of a paediatric road traffic injury (RTI) prevention programme in urban Sub-Saharan Africa. SETTING: Dares Salaam, Republic of Tanzania. METHODS: Household surveys were conducted in catchment areas around 18 primary schools in Dar es Salaam, Republic of Tanzania; the catchment areas were divided into control and intervention groups. Collected data included basic demographic information on all school-aged household members and whether or not they had been involved in an RTI in the previous 12 months, and, if so, what the characteristics of that RTI were. Based on these findings, a separate road safety engineering site analysis and consultation with the communities and other stakeholders, an injury-prevention programme was developed and implemented, consisting of infrastructure enhancements and a site-specific educational programme. The programme was initially implemented at the intervention schools. After 1 year, data were collected in the same manner. The control group received the same intervention after follow-up data were collected. RESULTS: Data were collected on 12 957 school-aged children in the baseline period and 13 555 school-aged children in the post-intervention period, in both the control and intervention communities. There was a statistically significant reduction in RTIs in the intervention group and a non-significant increase in RTI in the control group. The greatest reduction was in motorcycle-pedestrian RTI, private vehicle-pedestrian RTI and morning RTI. CONCLUSION: The programme demonstrated a significant reduction in paediatric RTI after its implementation, in very specific ways. This study demonstrates that for a reasonable investment, scientifically driven injury-prevention programmes are feasible in resource-limited settings with high paediatric RTI rates.


Asunto(s)
Prevención de Accidentes/métodos , Accidentes de Tránsito/prevención & control , Heridas y Lesiones/prevención & control , Adolescente , Entorno Construido , Niño , Femenino , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , Instituciones Académicas , Tanzanía
2.
Nurs Res ; 68(2): E11-E20, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30829926

RESUMEN

BACKGROUND: Precision health relies on large sample sizes to ensure adequate power, generalizability, and replicability; however, a critical first step to any study is the successful recruitment of participants. OBJECTIVES: This study seeks to explore how the enrollment strategies used in a parent study contributed to the high consent rates, establish current best practices that can be used in future studies, and identify additional factors that contribute to consent into pediatric traumatic brain injury biobanks. METHODS: Retrospective secondary analysis of data from a parent study with high consent rates was examined to explore factors affecting consent into biobanking studies. RESULTS: Of the 76 subjects who were approached, met the eligibility criteria, and reviewed the consent form, only 16 (21.1%) declined to participate. The consented group (n = 60) represents 64.5% of those who met the eligibility criteria upon initial screening (n = 93) and 78.9% of those with confirmed eligibility (n = 76). Analysis of screening data suggested there were no major barriers to consenting individuals into this pediatric traumatic brain injury biobank. DISCUSSION: There were no demographic or research-related characteristics that significantly explained enrollment. Ethically, to obtain true informed consent, parents need to understand only their child's diagnosis, prognosis, and medical care, as well as the purpose of the proposed research and its risks and benefits. Researchers need to implement best practices, including a comprehensive review of census data to identify eligible participants to approach, a prescreening protocol, and effective consenting process to obtain informed consent so that precision care initiatives can be pursued.


Asunto(s)
Bancos de Muestras Biológicas/ética , Lesiones Traumáticas del Encéfalo , Consentimiento Paterno/ética , Padres/psicología , Pediatría/ética , Niño , Toma de Decisiones , Femenino , Humanos , Masculino , Relaciones Médico-Paciente/ética , Estudios Retrospectivos
3.
Cell Rep ; 43(4): 114121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38615320

RESUMEN

Metabolic reprogramming is a hallmark of cancer, enabling cancer cells to rapidly proliferate, invade, and metastasize. We show that creatine levels in metastatic breast cancer cell lines and secondary metastatic tumors are driven by the ubiquitous mitochondrial creatine kinase (CKMT1). We discover that, while CKMT1 is highly expressed in primary tumors and promotes cell viability, it is downregulated in metastasis. We further show that CKMT1 downregulation, as seen in breast cancer metastasis, drives up mitochondrial reactive oxygen species (ROS) levels. CKMT1 downregulation contributes to the migratory and invasive potential of cells by ROS-induced upregulation of adhesion and degradative factors, which can be reversed by antioxidant treatment. Our study thus reconciles conflicting evidence about the roles of metabolites in the creatine metabolic pathway in breast cancer progression and reveals that tight, context-dependent regulation of CKMT1 expression facilitates cell viability, cell migration, and cell invasion, which are hallmarks of metastatic spread.


Asunto(s)
Neoplasias de la Mama , Forma Mitocondrial de la Creatina-Quinasa , Especies Reactivas de Oxígeno , Animales , Femenino , Humanos , Ratones , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Línea Celular Tumoral , Movimiento Celular , Supervivencia Celular , Creatina Quinasa , Forma Mitocondrial de la Creatina-Quinasa/metabolismo , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Mitocondrias/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Especies Reactivas de Oxígeno/metabolismo
4.
World J Surg ; 36(3): 548-55, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22270987

RESUMEN

BACKGROUND: The World Health Assembly recently adopted a resolution to urge improved competency in the provision of injury care through medical education. This survey sought to investigate trauma education experience and competency among final year medical students worldwide. METHODS: An Internet survey was distributed to medical students and conducted from March 2008 to January 2009. Demographic data and questions pertaining to both instruction and attainment of specific skills in burn and trauma care were assessed. RESULTS: There were 776 responses from final year medical students in 77 countries, with at least 10 countries from each economic stratum. Over 93% of final year students reported receiving some form of trauma or burn training, with 79% reporting a minimum compulsory requirement. Students received theoretical instruction without practical exposure. Few felt prepared to undertake basic procedures, such as laceration repair (19%), vascular access (8%), or endotracheal intubation (21%). Over 99% agreed that trauma education should be mandatory, but only half felt prepared to provide basic care. Those from low income and low middle income countries felt better prepared to provide trauma care than students from high middle and high income countries. CONCLUSIONS: Trauma education and experience varies among medical students in different countries. Many critical concepts are not formally taught and practical experience with many basic procedures is often lacking. The present study confirms that the trauma care training received by medical students needs to be strengthened in countries at all economic levels.


Asunto(s)
Quemaduras/cirugía , Competencia Clínica , Educación de Pregrado en Medicina , Cirugía General/educación , Heridas y Lesiones/cirugía , Curriculum , Educación de Pregrado en Medicina/normas , Salud Global , Encuestas de Atención de la Salud , Humanos , Laceraciones/cirugía
5.
Inj Prev ; 17(5): 309-12, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21422026

RESUMEN

OBJECTIVE/SETTING: To provide a population-based analysis of childhood road traffic injuries (RTI) in two communities of the greater Accra region of Ghana, with the goal of establishing an RTI incidence baseline in these communities and to identify RTI characteristics in order to model a targeted injury prevention programme. STUDY DESIGN: Geographical cluster sampling was performed in two separate communities with household surveys administered in person to determine a denominator. The guardian responsible for any household members below the age of 15 years involved in an RTI within the previous 12 months received an in-depth questionnaire. Demographics, incident characteristics, medical attention, injuries and disability days were noted. These are described and compared with injury severity and age-specific tendencies. RESULTS: 5128 children were interviewed in 60 clusters. Of them, 172 were involved in an RTI within the previous 12 months. This resulted in a rate of 34 RTI/1000 person-years, and 43 RTI/1000 person-years in the 5-14-year-old age group. RTI involving a mini-bus taxi, as a pedestrian, correlated with a disability of greater than 30 days, as did fractures. 35.8% of injuries occurred at sunset. Most RTI occurred on a highway and involved the lower extremities. There were two deaths resulting in an incidence of 39.0/100,000 person-years. CONCLUSION: Childhood RTI in this urban west African setting are a major source of disability. Specific injury circumstances are reviewed in detail. This study provides baseline incidence data that may be used to measure injury prevention efforts and to validate secondary data sources.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Adolescente , Niño , Preescolar , Femenino , Ghana/epidemiología , Humanos , Incidencia , Masculino , Salud Urbana/estadística & datos numéricos
6.
J Med Case Rep ; 15(1): 307, 2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-34049568

RESUMEN

BACKGROUND: We report our findings in a patient who developed central retinal vein occlusion (CRVO) and was a chronic user of olanzapine, an antipsychotic medication. CASE PRESENTATION: A 50-year-old Caucasian man, non-smoker, was referred to our clinic with the chief complaint of floater appearance in his left eye for the past 3 days. His past medical history indicated that he had been taking antipsychotic drugs (olanzapine) for about 3 years, with no other systemic disease or risk factors for CRVO. In the examination, his best-corrected visual acuity (BCVA) was 0.7 in the left eye. The fundus showed signs of nonischemic CRVO with subhyaloid hemorrhage and intraretinal hemorrhage in the posterior pole and superior and inferior retina, without macular edema, confirmed by optical coherence tomography (OCT). We ruled out other probable differential diagnoses and risk factors which lead to CRVO through a complete physical exam and blood analysis (complete blood count, glucose, urea, creatinine, lipid profile, erythrocyte sedimentation rate, C-reactive protein, prothrombin time, partial thromboplastin time, Bleeding time (BT), fibrinogen level, proteins, antiphospholipid antibodies, homocysteine blood level, antithrombin III, protein C and S, factor V Leiden, prothrombin mutation, angiotensin-converting enzyme level, other autoantibodies, and human leukocyte antigen [HLA]-B51). Finally, we confirmed the probable side effect of olanzapine in CRVO, which has not been previously reported. A possible pro-thrombogenic mechanism of olanzapine at the molecular level is an affinity for 5-HT2Aserotonin receptors. Blocking these receptors results in increased platelet aggregation and increased blood coagulability. CONCLUSIONS: These results indicate that CRVO can be a complication of chronic use of antipsychotic medications such as olanzapine, as shown for the first time in our case report. Clinicians should question patients who develop a sudden CRVO whether they are using antipsychotic medications such as olanzapine.


Asunto(s)
Antipsicóticos , Edema Macular , Oclusión de la Vena Retiniana , Antipsicóticos/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Olanzapina/efectos adversos , Oclusión de la Vena Retiniana/inducido químicamente , Agudeza Visual
7.
Am J Forensic Med Pathol ; 31(4): 388-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21063199

RESUMEN

We present a case from the Johannesburg General Hospital of a zone II low-velocity penetrating neck injury with involvement of the ipsilateral subclavian artery. When the "bullet" was retrieved, it was noted not to be an actual bullet but rather a cartridge casing. We speculate that this injury represents one of several possible misfiring scenarios from a homemade firearm. Injuries from homemade firearms are infrequent in the literature, and only one other similar case of a cartridge casing causing a penetrating injury was found. A brief review of homemade handheld firearms is offered.


Asunto(s)
Venas Yugulares/lesiones , Traumatismos del Cuello/etiología , Arteria Subclavia/lesiones , Armas , Heridas Penetrantes/etiología , Adulto , Diseño de Equipo , Humanos , Venas Yugulares/patología , Venas Yugulares/cirugía , Masculino , Traumatismos del Cuello/patología , Sudáfrica , Arteria Subclavia/patología , Arteria Subclavia/cirugía , Heridas Penetrantes/patología
8.
Rev Med Inst Mex Seguro Soc ; 48(2): 205-8, 2010.
Artículo en Español | MEDLINE | ID: mdl-20929626

RESUMEN

The calcifying epithelial odontogenic tumor known as Pindborg's tumor, is a rare odontogenic neoplasm of the jaws. One of their characteristics is the cortical expansion and the relationship with a non erupted tooth. Since the original description in 1955, only 200 cases approximately have been described in the world literature. This article reviews the literature and describes a case of patient who presented calcifying epithelial odontogenic tumor in the jaw undergoing surgical excision treatment with an evolution without complications.


Asunto(s)
Neoplasias Mandibulares , Tumores Odontogénicos , Adulto , Calcinosis/complicaciones , Calcinosis/diagnóstico , Calcinosis/cirugía , Femenino , Humanos , Enfermedades Mandibulares/complicaciones , Enfermedades Mandibulares/diagnóstico , Enfermedades Mandibulares/cirugía , Neoplasias Mandibulares/complicaciones , Neoplasias Mandibulares/diagnóstico , Neoplasias Mandibulares/cirugía , Tumores Odontogénicos/complicaciones , Tumores Odontogénicos/diagnóstico , Tumores Odontogénicos/cirugía
9.
Front Immunol ; 11: 2142, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33072077

RESUMEN

Human herpesvirus-6A (HHV-6A) and -6B (HHV-6B) might be involved in the etiopathogenesis of multiple sclerosis (MS), especially the HHV-6A. We aim at assessing, for the first time in the scientific literature, the HHV-6A/B microRNAs in MS patients. We analyzed the miRNAs of HHV-6A: miR-U86, and -6B: hhv6b-miR-Ro6-1, -2, -3-3p, -3-5p, and -4 in paired samples of serum and CSF of 42 untreated MS patients and 23 patients with other neurological diseases (OND), using Taqman MicroRNA Assays. Intrathecal HHV-6A/B antibody production and anti-HHV-6A/B IgG/IgM levels in serum were measured. MS clinical data were available. We detected the following miRNAs: hhv6b-miR-Ro6-2 (serum: MS:97.7%, OND:95.7%; CSF: MS:81%, OND:86.4%), 3-3p (serum: MS:4.8%, OND:0%; CSF: MS:2.4%, OND:4.5%), -3-5p (serum: MS:95.2%, OND:91.3%; CSF: MS:50%, OND:54.5%), and miR-U86 (serum: MS:54.8%, OND:47.8%; CSF: MS:11.9%, OND:9.1%). In the serum of the whole population (MS and OND patients) we found a significant correlation between the levels of hhv6b-miR-Ro6-2 and -3-5p (Spearman r = 0.839, pcorr = 3E-13), -2 and miR-U86 (Spearman r = 0.578, pcorr = 0.001) and -3-5p and miR-U86 (Spearman r = 0.698, pcorr = 1.34E-5); also in the CSF, between hhv6b-miR-Ro6-2 and -3-5p (Spearman r = 0.626, pcorr = 8.52E-4). These correlations remained statistically significant when both populations were considered separately. The anti-HHV-6A/B IgG levels in CSF and the intrathecal antibody production in positive MS patients for hhv6b-miR-Ro6-3-5p were statistically significant higher than in the negative ones (pcorr = 0.006 and pcorr = 0.036). The prevalence of miR-U86 (30.8%) in the CSF of individuals without gadolinium-enhancing lesions was higher (p = 0.035) than in the ones with these lesions (0%); however, the difference did not withstand Bonferroni correction (pcorr = 0.105). We propose a role of HHV-6A/B miRNAs in the maintenance of the viral latency state. Further investigations are warranted to validate these results and clarify the function of these viral miRNAs.


Asunto(s)
Herpesvirus Humano 6/aislamiento & purificación , MicroARNs/sangre , MicroARNs/líquido cefalorraquídeo , Esclerosis Múltiple/virología , ARN Viral/sangre , Adulto , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/líquido cefalorraquídeo , Estudios de Casos y Controles , Femenino , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/líquido cefalorraquídeo , Inmunoglobulina M/sangre , Inmunoglobulina M/líquido cefalorraquídeo , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/sangre , Esclerosis Múltiple/líquido cefalorraquídeo , Esclerosis Múltiple/diagnóstico por imagen , Enfermedades del Sistema Nervioso/sangre , Enfermedades del Sistema Nervioso/líquido cefalorraquídeo , ARN Viral/líquido cefalorraquídeo , Estudios Retrospectivos , Latencia del Virus/genética
10.
Dis Aquat Organ ; 78(2): 173-7, 2007 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-18286815

RESUMEN

This is the first description of a dorsoventral transposition of the heart chambers in sturgeons Acipenser naccarii. The affected individuals were 2 farmed alevins aged 9 and 10 d posthatching, respectively. One was examined by light microscopy and the other by scanning electron microscopy. In both cases, the atrium and sinus venosus occupied a left ventrolateral position, the ventricle, conus arteriosus and bulbus arteriosus were located dorsally, and the transverse septum was incomplete. The anomalous heart examined by light microscopy did not differ histologically from normal hearts of similar developmental stages. The abnormal dorsoventral arrangement of the heart chambers was presumably due to a distortion of the morphogenetic movements that bring the ventricle to the ventral and the atrium to the dorsal position. The present findings, together with genetic data reported in the literature, suggest that the defective cardiac phenotype detected in the present specimens might result from a mutation affecting the sturgeon ortholog of the zebrafish overlooped (olp) gene.


Asunto(s)
Enfermedades de los Peces/congénito , Enfermedades de los Peces/patología , Peces/anomalías , Cardiopatías Congénitas/veterinaria , Animales , Cardiopatías Congénitas/patología , Microscopía Electrónica de Rastreo/veterinaria
11.
Materials (Basel) ; 10(2)2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28772536

RESUMEN

The effect of porosity on the thermal conductivity and the coefficient of thermal expansion of composites obtained by infiltration of Al-12 wt % Si alloy into graphite particulate preforms has been determined. Highly irregular graphite particles were used to fabricate the preforms. The thermal conductivity of these composites gradually increases with the applied infiltration pressure given the inherent reduction in porosity. A simple application of the Hasselman-Johnson model in a two-step procedure (that accounts for the presence of both graphite particles and voids randomly dispersed in a metallic matrix) offers a good estimation of the experimental results. As concerns the coefficient of thermal expansion, the results show a slight increase with saturation being approximately in the range 14.6-15.2 × 10-6 K-1 for a saturation varying from 86% up to 100%. Results lie within the standard Hashin-Strikman bounds.

12.
Traffic Inj Prev ; 16(5): 456-60, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25356935

RESUMEN

OBJECTIVE: Road traffic injuries (RTIs) are a major public health burden, especially in low- and middle-income countries. There is limited data on RTIs in low-volume, rural African settings. This study attempted to survey all individuals living in households within 200 m of two low-volume rural roads in Tanzania and to collect data on RTIs. METHODS: Local communities and users of the Bago to Talawanda road (intervention site) and Kikaro to Mihuga road (control site) were targeted and received an intensive program of road safety measures tailored using the crash characteristics of the baseline sample. Demographic data on all household members were collected, and those individuals who suffered an RTI in the previous 3 months had comprehensive information collected about the crash characteristics and the socioeconomic impact. The follow-up data collection occurred nine months after the baseline data were collected. RESULTS: The majority of crashes that caused an RTI involved a motorcycle (71%) and the majority of victims were male (82%) with an average age of 27. Injuries to the legs (55%) were most common and the average length of time away from normal activity was 27 (±33) days. RTI incidence at the intervention site increased during the course of the study (incidence before vs. incidence after) and was unchanged in the community control (incidence before vs. incidence after). CONCLUSION: The incidence of RTIs in the low-volume rural setting is unacceptably high and most commonly associated with motorcycles. The change in incidence is unreliable due to logistic restraints of the project and more research is needed to quantify the impact of various RTI prevention strategies in this setting. This study provides insight into road traffic injuries on low-volume rural roads, areas where very little research has been captured. Additionally, it provides a replicable study design for those interested in collecting similar data on low-volume rural roads.


Asunto(s)
Accidentes de Tránsito/prevención & control , Accidentes de Tránsito/estadística & datos numéricos , Población Rural , Heridas y Lesiones/epidemiología , Heridas y Lesiones/prevención & control , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Motocicletas/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud , Seguridad , Tanzanía/epidemiología , Adulto Joven
13.
Rev Med Inst Mex Seguro Soc ; 53(6): 728-31, 2015.
Artículo en Español | MEDLINE | ID: mdl-26506491

RESUMEN

BACKGROUND: The aim of this study is to compare two different preparations in patients undergoing transrectal prostate biopsies samples (TPBS) and assess the prevalence of genitourinary infections (GUI). METHODS: A historical cohort of patients undergoing TBPS for suspected prostate cancer. Two groups were compared: one with endorectal lubricant jelly and another with the addition of a povidone-iodine lubricating jelly. Complications were evaluated at three weeks. A bivariate analysis was performed by calculating the OR (95 % CI) to determine if the additional endorectal povidone-iodine pre-TBPS reduced GUI and other complications. RESULTS: 185 patients (Group I n = 86, Group II n = 96) were evaluated. 45 and 25 % had genitourinary tract infection (OR: 0.4, CI: 0.2-0.9, p = 0.004); fever was presented in 21 and 10 % respectively (OR: 0.42, CI: 0.1-0.9, p = 0.04). CONCLUSIONS: A reduction was observed in the presence of genitourinary infections in patients who had intrarectal povidone-iodine preparation applied.


Introducción: el objetivo de este estudio es comparar dos preparaciones distintas en pacientes sometidos a la toma de biopsias prostáticas transrectales (BPTR) y evaluar la prevalencia de infecciones genitourinarias (IGU). Métodos: se compararon dos grupos de pacientes con sospecha de cáncer de próstata sometidos a Biopsia Prostática Transrectal (BPTR): Con jalea lubricante endorrectal (grupo l, cohorte histórica) y con jalea lubricante más iodopovidona (grupo II, cohorte prospectiva). Se evaluaron las complicaciones a las tres semanas. Se realizó un análisis bivariado, calculando su OR (IC: 95 %) para determinar si la iodopovidona endorrectal adicional previa a la BPTR disminuye las IGU y otras complicaciones. Resultados: Se evaluaron 185 pacientes (Grupo I n = 86; grupo II n = 96). Tuvieron infección del tracto genitourinario el 45 y 25 % (OR: 0.4, IC: 0.2-0.9, p = 0.004); la fiebre se presentó en el 21 y 10 % respectivamente (OR: 0.42, IC: 0.1-0.9, p = 0.04). Conclusiones: Se observó una reducción en la presencia de infecciones genitourinarias en pacientes a quienes se aplicó en su preparación iodopovidona intrarrectal.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Enfermedades de los Genitales Masculinos/prevención & control , Povidona Yodada/administración & dosificación , Próstata/patología , Infecciones Urinarias/prevención & control , Administración Rectal , Anciano , Antiinfecciosos Locales/uso terapéutico , Biopsia , Enfermedades de los Genitales Masculinos/epidemiología , Enfermedades de los Genitales Masculinos/etiología , Humanos , Masculino , Persona de Mediana Edad , Povidona Yodada/uso terapéutico , Estudios Prospectivos , Neoplasias de la Próstata/patología , Resultado del Tratamiento , Infecciones Urinarias/epidemiología , Infecciones Urinarias/etiología
14.
J Morphol ; 258(1): 97-105, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12905537

RESUMEN

Cartilaginous deposits are regularly present in the heart of several reptilian, avian, and mammalian species. The formation of these extraskeletal cartilages has been studied in birds and mammals, but not in reptiles. The aim here was to elucidate this question in the Spanish terrapin. Hearts from 23 embryos belonging to Yntema (1968) developmental stages 17 to 26 and eight terrapins age 3 months to 10 years were examined using histological, histochemical, and immunohistochemical techniques. In the heart of the Spanish terrapin (Mauremys leprosa), chondrogenesis can start during embryonic life. Cartilaginous tissue develops from a mesenchymal cellular condensation that extends along the aorticopulmonary septum and the incipient pars fibrosa of the ventricular horizontal septum. This cellular condensation, which is smooth muscle alpha-actin (SMalpha-actin)-negative and type II collagen-negative during stages 17 to 22, acts as a prechondrogenic condensation. In stage 23, production of type II collagen begins in the central core of the condensation and gradually spreads toward its periphery. The type II collagen-positive (chondrogenic) cellular condensation remains devoid of perichondrium prior to birth. Thereafter, it converts into hyaline cartilage that extends along the proximal part of the aorticopulmonary septum and the pars fibrosa of the horizontal septum. Our findings are consistent with the assumption that, as in birds and mammals, the precursors of the cardiac chondrocytes in chelonians are neural crest-derived cells of nonmuscular nature. In addition, they point to the possibility that cells from the neural crest populate the embryonic pars fibrosa of the horizontal septum, thereby contributing to its alignment with the aorticopulmonary septum. In the present species, a second cartilaginous deposit of a hyaline nature extends along the sinus wall of the right semilunar valve of the right aorta, penetrating the fibrous cushion that constitutes the proximal support of the corresponding valve leaflet. This cartilage develops after birth, between the third and eighteenth month of life; its morphogenetic origin is unclear. The cartilaginous foci occurring in hearts of Spanish terrapin appear to act as pivots resisting mechanical tensions generated during the cardiac cycle. In the specimens examined there was no sign of replacement of the cardiac cartilages by bone tissue.


Asunto(s)
Cartílago/fisiología , Corazón/anatomía & histología , Corazón/crecimiento & desarrollo , Tortugas , Envejecimiento , Animales , Femenino , Tortugas/anatomía & histología , Tortugas/embriología , Tortugas/crecimiento & desarrollo
15.
J Morphol ; 260(2): 172-83, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15108157

RESUMEN

Previous work showed that in the adult sturgeon an intrapericardial, nonmyocardial segment is interposed between the conus arteriosus of the heart and the ventral aorta. The present report illustrates the ontogeny of this intermediate segment in Acipenser naccarii. The sample studied consisted of 178 alevins between 1 and 24 days posthatching. They were examined using light and electron microscopy. Our observations indicate that the entire cardiac outflow tract displays a myocardial character during early development. Between the fourth and sixth days posthatching, the distal portion of the cardiac outflow tract undergoes a phenotypical transition, from a myocardial to a smooth muscle-like phenotype. The length of this region with regard to the whole outflow tract increases only moderately during subsequent developmental stages, becoming more and more cellularized. The cells soon organize into a pattern that resembles that of the arterial wall. Elastin appears at this site by the seventh day posthatching. Therefore, two distinct components, proximal and distal, can be recognized from the fourth day posthatching in the cardiac outflow tract of A. naccarii. The proximal component is the conus arteriosus, characterized by its myocardial nature and the presence of endocardial cushions. The distal component transforms into the intrapericardial, nonmyocardial segment mentioned above, which is unequivocally of cardiac origin. We propose to designate this segment the "bulbus arteriosus" because it is morphogenetically equivalent to the bulbus arteriosus of teleosts. The present findings, together with data from the literature, point to the possibility that cells from the cardiac neural crest are involved in the phenotypical transition that takes place at the distal portion of the cardiac outflow tract, resulting in the appearance of the bulbus arteriosus. Moreover, they suggest that the cardiac outflow tract came to be formed by a bulbus arteriosus and a conus arteriosus from an early period of the vertebrate evolutionary story. Finally, we hypothesize that the embryonic truncus of birds and mammals is homologous to the bulbus arteriosus of fish.


Asunto(s)
Evolución Biológica , Peces/embriología , Tronco Arterial/embriología , Animales , Peces/anatomía & histología , Microscopía Electrónica de Rastreo , Tronco Arterial/ultraestructura
16.
Anat Embryol (Berl) ; 208(6): 439-49, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15322872

RESUMEN

This paper presents a sequential analysis of the development of the sturgeon (Acipenser naccarii) heart from the end of gastrulation to the early juvenile stages. At late neurulation, the heart appears as a straight, short tube located over the endoderm that forms the wall of the yolk sac, in front of the developing head. The heart axis is aligned with the axis of the developing head. Subsequently, the heart elongates and adopts a C-shape, and its axis becomes perpendicular to that of the head. Around the time of hatching, the heart loses the loop and appears as a mostly straight tube with the chambers arranged in a craniocaudal sequence: outflow tract, ventricle, atrium, and a small sinus venosus. During the first 4 days post-hatching (dph), the heart starts looping again, adopts a C-shape, and undergoes a counterclockwise movement that brings the atrium to the left of the outflow tract and the ventricle to a caudal position. Thus, a primary and a secondary cardiac loop occur in the sturgeon. Later, the atria come to occupy a middle position behind the outflow tract, and the sinus venosus shifts from a caudal to a dorsal position. A morphological arrangement similar to that found in adult sturgeons is attained in all specimens at days 7-9 dph. The external changes are accompanied by a series of internal modifications that include trabeculation (3-4 dph), development of endocardial cushions in the atrioventricular canal (4 dph) and in the conus arteriosus (3-4 dph), conus (22-24 dph) and atrioventricular (18-20 dph) valve formation, and development of the epicardium (4 dph) and the coronary vessels (10 dph). The main developmental features of the heart have been registered, and a basic body of information, which should be very useful in future developmental studies, has been established. Similarities and dissimilarities between the development of the sturgeon heart and that of other vertebrates are underscored.


Asunto(s)
Peces/embriología , Corazón/embriología , Organogénesis/fisiología , Animales , Peces/anatomía & histología , Corazón/anatomía & histología , Microscopía Electrónica de Rastreo , Morfogénesis , Miocardio/ultraestructura
17.
Rev. colomb. cardiol ; 26(1): 17-23, ene.-feb. 2019. tab, graf
Artículo en Español | LILACS, COLNAL | ID: biblio-1058375

RESUMEN

Resumen Objetivo: Estimar la razón de costo-efectividad de la reanimación cardiopulmonar con el uso del desfibrilador externo automático (DEA), comparado con la reanimación cardiopulmonar básica, para la reanimación de personas con pérdida de conciencia en espacios de afluencia masiva de público en Colombia. Métodos: Para estimar los costos y desenlaces de las dos alternativas de comparación, se diseñó un árbol de decisiones en el cual se reflejan los principales desenlaces posterior a la pérdida de conciencia y la reanimación con cualquiera de las dos alternativas. Se asumió la perspectiva del sistema de salud colombiano en un horizonte temporal comprendido entre el momento de la pérdida de conciencia de la persona hasta el ingreso al hospital. Las probabilidades de los eventos se obtuvieron de un meta-análisis de ensayos clínicos y la información de costos de fuentes oficiales y consulta directa a proveedores de DEA en Colombia. Los costos fueron expresados en pesos colombianos de 2016 y la efectividad en muertes evitadas. Se realizaron análisis de sensibilidad determinísticos y probabilísticos para estimar el impacto de la incertidumbre sobre las conclusiones. Resultados: La razón de costo-efectividad de la reanimación cardiopulmonar con DEA fue de $3.267.777 por muerte evitada. La probabilidad de que esta intervención sea costo-efectiva es superior al 90% para un umbral de costo-efectividad superior a 10 millones de pesos. Conclusión: Un programa de reanimación cardiopulmonar con desfibrilación temprana mediante el uso de DEA, en espacios de afluencia masiva de público, es una alternativa costo-efectiva para el sistema de salud colombiano.


Abstract Objective: To estimate the cost-effectiveness of cardiopulmonary resuscitation using an automated external defibrillator (AED) compared with basic cardiopulmonary resuscitation, for the resuscitation of unconscious patients in crowded public spaces in Colombia. Methods: A decision tree was designed in order to estimate the costs and outcomes of the two alternatives. This included the main outcomes after the loss of consciousness and resuscitation by any of the two alternatives. The perspective of the Colombian Health System was adopted in a time scale consisting of the time of loss of consciousness until hospital admission. The probabilities of the events were obtained from a meta-analysis of clinical trials, and the information on costs from official sources and direct consultations with AED providers in Colombia. The costs were expressed in Colombian pesos of 2016, and the effectiveness in deaths prevented. Deterministic and probabilistic sensitivity analyses were performed to estimate the impact of uncertainty on the conclusions. Results: The cost-effectiveness of cardiopulmonary resuscitation with AED was COP $3,267,777 per death avoided. The probability that this intervention would be cost-effective is greater than 90% for cost-effectiveness threshold greater than 10 million Colombian pesos. Conclusion: A cardiopulmonary resuscitation program with early defibrillation using an AED in crowded public spaces is a cost-effective alternative for the Colombian Health System.


Asunto(s)
Humanos , Costos y Análisis de Costo , Desfibriladores , Análisis de Costo-Efectividad , Inconsciencia , Reanimación Cardiopulmonar , Participación de la Comunidad
18.
Mar Pollut Bull ; 69(1-2): 165-71, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23465569

RESUMEN

Marine fish farms could cause environmental disturbances on the sediment due to uneaten food and fish faeces that impact the marine benthos. Polychaete assemblages are considered good indicators of environmental perturbations. The present study aimed to establish groups of polychaetes as potential indicators of fish farm pollution. This study was carried out in ten fish farms along the Spanish coast. Changes in polychaete assemblage were analyzed with meta-analysis and multivariate techniques. Abundance, richness and diversity showed significant decreases under fish farm conditions. Distribution patterns of polychaetes responded to combinations of physicochemical variables. The main ones are sulfide concentration, silt and clays percentage, and stable nitrogen isotope ratio. The results showed that some families are tolerant, Capitellidae, Dorvilleidae, Glyceridae, Nereididae, Oweniidae and Spionidae; while others are sensitive to fish farm pollution, Magelonidae, Maldanidae, Nephtyidae, Onuphidae, Paralacydoniidae, Paraonide, Sabellidae and also Cirratulidae in spite of being reported as a tolerant family.


Asunto(s)
Acuicultura , Sedimentos Geológicos/química , Metaanálisis como Asunto , Poliquetos/clasificación , Contaminantes del Agua/análisis , Contaminación del Agua/estadística & datos numéricos , Animales , Biodiversidad , Monitoreo del Ambiente , Peces , Poliquetos/crecimiento & desarrollo , España
20.
Accid Anal Prev ; 45: 204-10, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22269502

RESUMEN

Road traffic injuries (RTI) are a public health threat and a major source of disability in developing countries. A population-based analysis of RTIs in a testimonially high-risk area of Dar es Salaam, the largest city in the East African country of Tanzania, was carried out with the goal of establishing an RTI incidence and to identify RTI characteristics that may be used for a targeted injury prevention program in these communities. Geographic cluster sampling was completed in 2 adjacent wards of Dar es Salaam with household surveys administered in person to determine a denominator. Any household members involved in an RTI within the previous 12 months received an in-depth questionnaire. Demographics, incident characteristics, medical attention, injuries and disability days were noted. These are described and compared to injury severity and age specific tendencies. Within the 30 clusters, 6001 individuals were interviewed. Of them, 196 were involved in non-fatal RTIs within the previous 12 months, resulting in a non-fatal incidence rate of 32.7 RTIs per 1000 person years. There were 4 deaths noted. Injuries resulting in a fracture correlated with a disability of more than 30 days. Children were injured as pedestrians 93% of the time and were more likely to be injured on small, unpaved side streets than adults. Most RTIs occurred on a highway and affected the lower extremities, required treatment at a hospital, and resulted in a police report being filed 50.2% of the time. In conclusion, RTIs in this urban East African setting are a major source of disability. This study provides incidence data and crash characteristics that may be used to construct prevention programs and could validate secondary data sources.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Países en Desarrollo , Heridas y Lesiones/epidemiología , Accidentes de Tránsito/prevención & control , Adolescente , Adulto , Factores de Edad , Causalidad , Niño , Preescolar , Estudios Transversales , Femenino , Sistemas de Información Geográfica , Humanos , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Encuestas y Cuestionarios , Tanzanía , Heridas y Lesiones/prevención & control , Adulto Joven
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