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1.
Mol Reprod Dev ; 90(6): 369-377, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37486100

RESUMO

Throughout the reproductive life of women, cumulus cells (CC) protect the dormant oocyte from damage, act as sensors of the follicular microenvironment, and act as a gatekeeper for oocyte developmental potential. One such mechanism relies on the hypoxia-tolerance response, which, with age, decreases systematically, including in the ovary. We aimed to evaluate the association between gene expression related to hypoxia and aging in CC and reproductive results in in vitro fertilization cycles. We recruited 94 women undergoing controlled ovarian stimulation. Total RNA was extracted from pooled CCs collected after oocyte pick-up (OPU) and reverse-transcribed to complementary DNA using random hexamers to test 14 genes related to hypoxia response via HIF1α activation, oxidative stress, and angiogenic responses. The expression of CLU, NOS2, and TXNIP had a positive correlation with age (rs = 0.25, rs = 0.24, and rs = 0.35, respectively). Additionally, NOS2 and HMOX1 expression correlated positively with the retrieval of immature oocytes (rs = 0.22 and rs = 0.40, respectively). Moreover, VEGFC levels decreased overall with increasing fertilization rate, independently of age (rs = -0.29). We found that the fertilization potential of a cohort of oocytes is related to the ability of CC to respond to oxidative stress and hypoxia with age, pointing at NOS2, HMOX1, and VEGFC expression as markers for oocyte maturation and fertilization success.


Assuntos
Células do Cúmulo , Oogênese , Feminino , Humanos , Células do Cúmulo/metabolismo , Fertilização/fisiologia , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Técnicas de Maturação in Vitro de Oócitos , Óxido Nítrico Sintase Tipo II/metabolismo , Oócitos/metabolismo , Oogênese/fisiologia
2.
Comput Struct Biotechnol J ; 21: 1473-1486, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36851916

RESUMO

Human complement is the first line of defence against invading pathogens and is involved in tissue homeostasis. Complement-targeted therapies to treat several diseases caused by a dysregulated complement are highly desirable. Despite huge efforts invested in their development, only very few are currently available, and a deeper understanding of the numerous interactions and complement regulation mechanisms is indispensable. Two important complement regulators are human Factor H (FH) and Factor H-related protein 1 (FHR1). MFHR1 and MFHR13, two promising therapeutic candidates based on these regulators, combine the dimerization and C5-regulatory domains of FHR1 with the central C3-regulatory and cell surface-recognition domains of FH. Here, we used AlphaFold2 to model the structure of these two synthetic regulators. Moreover, we used AlphaFold-Multimer (AFM) to study possible interactions of C3 fragments and membrane attack complex (MAC) components C5, C7 and C9 in complex with FHR1, MFHR1, MFHR13 as well as the best-known MAC regulators vitronectin (Vn), clusterin and CD59, whose experimental structures remain undetermined. AFM successfully predicted the binding interfaces of FHR1 and the synthetic regulators with C3 fragments and suggested binding to C3. The models revealed structural differences in binding to these ligands through different interfaces. Additionally, AFM predictions of Vn, clusterin or CD59 with C7 or C9 agreed with previously published experimental results. Because the role of FHR1 as MAC regulator has been controversial, we analysed possible interactions with C5, C7 and C9. AFM predicted interactions of FHR1 with proteins of the terminal complement complex (TCC) as indicated by experimental observations, and located the interfaces in FHR11-2 and FHR14-5. According to AFM prediction, FHR1 might partially block the C3b binding site in C5, inhibiting C5 activation, and block C5b-7 complex formation and C9 polymerization, with similar mechanisms of action as clusterin and vitronectin. Here, we generate hypotheses and give the basis for the design of rational approaches to understand the molecular mechanism of MAC inhibition, which will facilitate the development of further complement therapeutics.

3.
Front Bioeng Biotechnol ; 10: 837965, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252145

RESUMO

The moss Physcomitrella is an interesting production host for recombinant biopharmaceuticals. Here we produced MFHR1, a synthetic complement regulator which has been proposed for the treatment of diseases associated to the complement system as part of human innate immunity. We studied the impact of different operation modes for the production process in 5 L stirred-tank photobioreactors. The total amount of recombinant protein was doubled by using fed-batch or batch compared to semi-continuous operation, although the maximum specific productivity (mg MFHR1/g FW) increased just by 35%. We proposed an unstructured kinetic model which fits accurately with the experimental data in batch and semi-continuous operation under autotrophic conditions with 2% CO2 enrichment. The model is able to predict recombinant protein production, nitrate uptake and biomass growth, which is useful for process control and optimization. We investigated strategies to further increase MFHR1 production. While mixotrophic and heterotrophic conditions decreased the MFHR1-specific productivity compared to autotrophic conditions, addition of the phytohormone auxin (NAA, 10 µM) to the medium enhanced it by 470% in shaken flasks and up to 230% and 260%, in batch and fed-batch bioreactors, respectively. Supporting this finding, the auxin-synthesis inhibitor L-kynurenine (100 µM) decreased MFHR1 production significantly by 110% and 580% at day 7 and 18, respectively. Expression analysis revealed that the MFHR1 transgene, driven by the Physcomitrella actin5 (PpAct5) promoter, was upregulated 16 h after NAA addition and remained enhanced over the whole process, whereas the auxin-responsive gene PpIAA1A was upregulated within the first 2 hours, indicating that the effect of auxin on PpAct5 promoter-driven expression is indirect. Furthermore, the day of NAA supplementation was crucial, leading to an up to 8-fold increase of MFHR1-specific productivity (0.82 mg MFHR1/g fresh weight, 150 mg accumulated over 7 days) compared to the productivity reported previously. Our findings are likely to be applicable to other plant-based expression systems to increase biopharmaceutical production and yields.

4.
Cancers (Basel) ; 14(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35158957

RESUMO

Colorectal cancer liver metastases (CRC-LM) present differential histologic growth patterns (HGP) that determine the interaction between immune and tumor cells. We explored the spatial distribution of lymphocytic infiltrates in CRC-LM in the context of the HGP using multispectral digital pathology. We did not find statistically significant differences of immune cell densities in the central regions of desmoplastic (dHGP) and non-desmoplastic (ndHGP) metastases. The spatial evaluation reported that dHGP-metastases displayed higher infiltration by CD8+ and CD20+ cells in peripheral regions as well as CD4+ and CD45RO+ cells in ndHGP-metastases. However, the reactive stroma regions at the invasive margin (IM) of ndHGP-metastases displayed higher density of CD4+, CD20+, and CD45RO+ cells. The antitumor status of the TIL infiltrates measured as CD8/CD4 reported higher values in the IM of encapsulated metastases up to 400 µm towards the tumor center (p < 0.05). Remarkably, the IM of dHGP-metastases was characterized by higher infiltration of CD8+ cells in the epithelial compartment parameter assessed with the ratio CD8epithelial/CD8stromal, suggesting anti-tumoral activity in the encapsulating lesions. Taking together, the amount of CD8+ cells is comparable in the IM of both HGP metastases types. However, in dHGP-metastases some cytotoxic cells reach the tumor nests while remaining retained in the stromal areas in ndHGP-metastases.

5.
Commun Biol ; 5(1): 152, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35194132

RESUMO

The complement system constitutes the innate defense against pathogens. Its dysregulation leads to diseases and is a critical determinant in many viral infections, e.g., COVID-19. Factor H (FH) is the main regulator of the alternative pathway of complement activation and could be a therapy to restore homeostasis. However, recombinant FH is not available. Engineered FH versions may be alternative therapeutics. Here, we designed a synthetic protein, MFHR13, as a multitarget complement regulator. It combines the dimerization and C5-regulatory domains of human FH-related protein 1 (FHR1) with the C3-regulatory and cell surface recognition domains of human FH, including SCR 13. In summary, the fusion protein MFHR13 comprises SCRs FHR11-2:FH1-4:FH13:FH19-20. It protects sheep erythrocytes from complement attack exhibiting 26 and 4-fold the regulatory activity of eculizumab and human FH, respectively. Furthermore, we demonstrate that MFHR13 and FHR1 bind to all proteins forming the membrane attack complex, which contributes to the mechanistic understanding of FHR1. We consider MFHR13 a promising candidate as therapeutic for complement-associated diseases.


Assuntos
Proteínas Sanguíneas/metabolismo , Ativação do Complemento , Fator H do Complemento/metabolismo , Proteínas do Sistema Complemento/metabolismo , Eritrócitos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Sequência de Aminoácidos , Animais , Bryopsida/genética , Bryopsida/metabolismo , COVID-19/epidemiologia , COVID-19/metabolismo , COVID-19/virologia , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Humanos , Modelos Moleculares , Pandemias/prevenção & controle , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , SARS-CoV-2/fisiologia , Ovinos
6.
Polymers (Basel) ; 13(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34771169

RESUMO

The latest advances in green alternatives are being addressed with bio-based solutions, with uses and applications in new areas due to their wide potential, low cost, lightness, renewability, biodegradability, impact toughness, fatigue resistance, and other specific properties. Natural fibers are sustainable materials that have led researchers to test their viability as alternative reinforcements in residual polymers to meet required engineering specifications; therefore, it is essential to continue making progress in replacing conventional materials. This review is expected to provide an overview of the current scopes and future prospects of biocomposites from polymers reinforced with natural fibers with a focus on the following: i. recycling of residual polymers; ii. available natural fibers and their components in the context of engineering applications; iii. the behavior of the structural modifications of the natural fibers with the physical and chemical treatments in the matrix interaction as reinforcements of the residual polymers; and iv. applications for the development of innovative, efficient, and sustainable solutions for successful, environmentally responsible products.

7.
Int J Surg Case Rep ; 88: 106565, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34741863

RESUMO

INTRODUCTION AND IMPORTANCE: Vascular smooth muscle sarcomas are rare neoplasms that comprise less than 2% of all leiomyosarcomas. These malignancies usually originate in the inferior vena cava, with a limited number of cases affecting the great saphenous vein. Due to the limited reports on these sarcomas, epidemiologic data remains insufficient. CASE PRESENTATION: We report the case of a 67-year-old Hispanic female that presented with an asymptomatic growing mass in her right thigh. She was managed with an En bloc resection under the impression of a smooth muscle vascular sarcoma. The diagnosis was confirmed after histopathologic evaluation. CLINICAL DISCUSSION: Vascular leiomyosarcomas remain a rare and challenging diagnosis. They usually present as a slowly growing mass that is initially asymptomatic. High clinical suspicion and a comprehensive radiologic evaluation, including magnetic resonance imaging, are crucial. Histopathological evaluation is essential for diagnostic confirmation. Surgical excision remains the treatment of choice, with radiation therapy mostly considered for local disease control. Postsurgical surveillance is necessary every three months to monitor for signs of recurrence. CONCLUSION: Physicians should remain aware of the nonspecific presentation of leiomyosarcomas and the importance of a comprehensive diagnostic approach. Early diagnosis and adequate management are fundamental elements in the treatment of these aggressive tumors.

8.
Acta bioquím. clín. latinoam ; 54(4): 437-453, jul. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1149033

RESUMO

Resumen El sistema del complemento juega un papel central en la inmunidad innata, es una línea de defensa contra patógenos y participa en la homeostasis. La activación anormal del complemento contribuye al desarrollo de patologías de variable severidad, tanto inmunológicas y hematológicas como renales. Entre ellas, las microangiopatías trombóticas (MAT) representan un grupo de enfermedades raras con manifestaciones clínicas comunes caracterizadas por anemia hemolítica no inmune, trombocitopenia y daño de órgano(s) blanco. Si bien la clasificación de las MAT sigue siendo desafiante y no ha sido internacionalmente estandarizada, la descripción de entidades asociadas a anomalías del complemento fue comprobada con la eficiencia de la terapia anticomplemento en los pacientes. Las herramientas de diagnóstico desarrolladas en las últimas décadas son esenciales actualmente para diferenciar las MAT más características del grupo; esto es, la púrpura trombótica trombocitopénica (PTT) y el síndrome urémico hemolítico (SUH). En el presente trabajo se presenta una revisión del funcionamiento del sistema del complemento en condiciones fisiológicas, para poder explicar luego cuáles son las alteraciones del sistema implicadas en el desarrollo de las MAT y describir las herramientas disponibles para detectarlas en el laboratorio.


Abstract The complement system plays a crucial role in the innate immune response, being the first-line defense against pathogens and regulating homeostasis. Uncontrolled complement activation can cause immunologic, hematologic as well as renal syndromes of variable severity. Among them, thrombotic microangiopathies (TMA) represent a group of rare diseases characterised by similar clinical manifestations such as microangiopathic hemolytic anemia (MAHA), peripheral thrombocytopenia and organ injury. Although TMA classification is still challenging and no international consensus has been reached, complement-associated disorders have been described thanks to the efficiency of anti-complement therapy in patients. Diagnostic tools developed in the last decades are essential to differentiate the two most well characterized TMA: thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). This review will describe how the complement system works in physiological conditions in order to explain how complement abnormalities are involved in TMA, and finally how to detect those anomalies using laboratory tests.


Resumo O sistema do complemento desempenha um papel central na imunidade inata, sendo uma linha de defesa contra patógenos e participando da homeostase. A ativação anormal do complemento contribui para o desenvolvimento de patologias de gravidade variável, como imunológicas, hematológicas e renais. Entre elas, as microangiopatias trombóticas (MAT) representam um grupo de doenças raras com manifestações clínicas comuns caracterizadas por anemia hemolítica não imune, trombocitopenia e lesão de órgão(s) alvo. Embora a classificação das MAT continue sendo desafiadora e não tenha sido padronizada internacionalmente, a descrição de entidades associadas a anomalias do complemento foi comprovada com a eficiência da terapia anticomplemento nos pacientes. As ferramentas de diagnóstico desenvolvidas nas últimas décadas são atualmente essenciais para diferenciar as MAT mais características do grupo, que são a púrpura trombocitopênica trombótica (PTT) e a síndrome hemolítica urêmica atípica (SHU). Neste trabalho, é apresentada uma revisão do funcionamento do sistema de complemento em condições fisiológicas, a fim de explicar posteriormente quais são as alterações do sistema compreendidas no desenvolvimento das MAT, e descrever as ferramentas disponíveis para detectá-las em laboratório.


Assuntos
Humanos , Biomarcadores/análise , Ativação do Complemento/fisiologia , Microangiopatias Trombóticas/diagnóstico , Trombocitopenia/diagnóstico , Síndrome Hemolítico-Urêmica Atípica/diagnóstico , Homeostase , Anemia Hemolítica/diagnóstico
9.
Front Plant Sci ; 11: 610032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391325

RESUMO

Recombinantly produced proteins are indispensable tools for medical applications. Since the majority of them are glycoproteins, their N-glycosylation profiles are major determinants for their activity, structural properties and safety. For therapeutical applications, a glycosylation pattern adapted to product and treatment requirements is advantageous. Physcomitrium patens (Physcomitrella, moss) is able to perform highly homogeneous complex-type N-glycosylation. Additionally, it has been glyco-engineered to eliminate plant-specific sugar residues by knock-out of the ß1,2-xylosyltransferase and α1,3-fucosyltransferase genes (Δxt/ft). Furthermore, Physcomitrella meets wide-ranging biopharmaceutical requirements such as GMP compliance, product safety, scalability and outstanding possibilities for precise genome engineering. However, all plants, in contrast to mammals, lack the capability to perform N-glycan sialylation. Since sialic acids are a common terminal modification on human N-glycans, the property to perform N-glycan sialylation is highly desired within the plant-based biopharmaceutical sector. In this study, we present the successful achievement of protein N-glycan sialylation in stably transformed Physcomitrella. The sialylation ability was achieved in a Δxt/ft moss line by stable expression of seven mammalian coding sequences combined with targeted organelle-specific localization of the encoded enzymes responsible for the generation of ß1,4-galactosylated acceptor N-glycans as well as the synthesis, activation, transport and transfer of sialic acid. Production of free (Neu5Ac) and activated (CMP-Neu5Ac) sialic acid was proven. The glycosidic anchor for the attachment of terminal sialic acid was generated by the introduction of a chimeric human ß1,4-galactosyltransferase gene under the simultaneous knock-out of the gene encoding the endogenous ß1,3-galactosyltransferase. Functional complex-type N-glycan sialylation was confirmed via mass spectrometric analysis of a stably co-expressed recombinant human protein.

10.
Ciudad Autónoma de Buenos Aires; Argentina. Ministerio de Salud de la Nación. Dirección de Investigación en Salud; 2020. 1-31 p. tab, graf.
Não convencional em Espanhol | ARGMSAL, BINACIS | ID: biblio-1379515

RESUMO

El suicidio representa un grave problema creciente de la salud pública en todo el planeta, y constituye la segunda causa de muerte en jóvenes y adolescente. Este estudio indaga el comportamiento de aspectos psicosociales de la suicidalidad en contexto de pandemia, en un conjunto de poblaciones rurales andinas. El objetivo general consiste en explorar los efectos del ASPO por COVID-19 en factores de riesgo y factores protectores de la suicidalidad adolescente del Departamento Calingassta (Provincia de San Juan (durante el año 2020. Mediante un diseño cuali-cuantitativo flexible, que considera emergentes, se administraron técnicas remotas de producción de datos -formularios digitales y entrevvistas semiestructuradas telefónicas- a referentes de instituciones comunitarias; y se accedió a registros oficiales de casos, así como a información originada en dispositivos virtuaes implementados en pandemia. El análisis incorporó elementos de la teoría fundamentada para elaborar categorías y comparó cifras oficiales, a fin de producir conocimientos situados. Los principales resutados obtenidos indican una disminución de casos de intentos de suicidio y suicidio consumado, aunque no es posible dimensionar con precisión la suicidalidad calingastina durante el ASPO debido a que los registros de ideación suicida y autolesiones no se encuentran sistematizados; si bien se advierten mejores condiciones de formación para su pesquisa y abordaje en agentes de la salud mental de salud pública. Se pusieron en visibilidad carencias de recursos de larga data, que conducen a centrarse en las demandas más urgentes en detrimento del desarrollo de actividades comunitarias de prevención y promoción de la saluld; y se evidenciaron necesidades de capacitación ante el desconocimiento de la Ley Nacional 27.130, y de refuerzo en redes entre dispositivos comunitarios departamentales, formales e informales.


Assuntos
Pesquisa Qualitativa
11.
Rev Med Chil ; 146(7): 862-868, 2018 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-30534885

RESUMO

BACKGROUND: Detecting patients at risk of falls during hospital stay is of utmost importance to implement preventive measures. AIM: To determine the frequency of patients with a high risk of falls admitted to a medical-surgical ward. To assess the preventive measures implemented. MATERIALS AND METHODS: Review of medical records of 376 patients aged 20 to 97 years (28% older than 70 years) admitted to a clinical hospital in a period of four months. RESULTS: Eleven percent of patients had a history of falls, 50% had a sensory deficit, 68% had unstable gait, 8% had a neurological risk condition, 8% had drowsiness or disorientation, 4% had psychomotor agitation or delirium, 86 % used high risk medications, 73% used 2 or more high risk drugs and 72% were using devices that decrease mobility. One hundred forty-one patients (38%) had a high risk of falling. The mean age of the latter was 77 years, 89% had a sensory deficit, 96% had unstable gait, 4% had psychomotor agitation or delirium and 98% used high risk drugs. Less than 1% had a medical prescription of a caregiver, physical restraints or antipsychotics, however, 21% of patients had a caregiver. CONCLUSIONS: The percentage of patients with a high risk of falling is important. The main risk factors were sensory deficit, unstable gait and the use of high risk medications. The low frequency of preventive measures prescriptions is striking.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Pacientes Internados/estatística & dados numéricos , Acidentes por Quedas/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Chile , Humanos , Incidência , Tempo de Internação , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
12.
Rev. méd. Chile ; 146(7): 862-868, jul. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-961472

RESUMO

Background: Detecting patients at risk of falls during hospital stay is of utmost importance to implement preventive measures. Aim: To determine the frequency of patients with a high risk of falls admitted to a medical-surgical ward. To assess the preventive measures implemented. Materials and Methods: Review of medical records of 376 patients aged 20 to 97 years (28% older than 70 years) admitted to a clinical hospital in a period of four months. Results: Eleven percent of patients had a history of falls, 50% had a sensory deficit, 68% had unstable gait, 8% had a neurological risk condition, 8% had drowsiness or disorientation, 4% had psychomotor agitation or delirium, 86 % used high risk medications, 73% used 2 or more high risk drugs and 72% were using devices that decrease mobility. One hundred forty-one patients (38%) had a high risk of falling. The mean age of the latter was 77 years, 89% had a sensory deficit, 96% had unstable gait, 4% had psychomotor agitation or delirium and 98% used high risk drugs. Less than 1% had a medical prescription of a caregiver, physical restraints or antipsychotics, however, 21% of patients had a caregiver. Conclusions: The percentage of patients with a high risk of falling is important. The main risk factors were sensory deficit, unstable gait and the use of high risk medications. The low frequency of preventive measures prescriptions is striking.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Acidentes por Quedas/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Pacientes Internados/estatística & dados numéricos , Acidentes por Quedas/prevenção & controle , Chile , Incidência , Fatores de Risco , Tempo de Internação
13.
Front Public Health ; 6: 141, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29876339

RESUMO

Sex hormones significantly impact women's lives. Throughout the different stages of life, from menarche to menopause and all stages in between, women experience dramatic fluctuations in the levels of progesterone and estradiol, among other hormones. These fluctuations affect the body as a whole, including the central nervous system (CNS). In the CNS, sex hormones act via steroid receptors. They also have an effect on different neurotransmitters such as GABA, serotonin, dopamine, and glutamate. Additionally, studies show that sex hormones and their metabolites influence brain areas that regulate mood, behavior, and cognitive abilities. This review emphasizes the benefits a proper hormonal balance during the different stages of life has in the CNS. To achieve this goal, it is essential that hormone levels are evaluated considering a woman's age and ovulatory status, so that a correct diagnosis and treatment can be made. Knowledge of steroid hormone activity in the brain will give women and health providers an important tool for improving their health and well-being.

14.
Acta biol. colomb ; 23(1): 115-123, Jan.-Apr. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-886091

RESUMO

RESUMEN Se midieron los flujos de materia orgánica aportados por la hojarasca al manantial de Cañaverales (La Guajira, Colombia), durante un período de seis meses (seco y lluvioso). La caída mensual fue de 0,17 t-ha-1mes-1, que extrapolada a un año representó 2,08 t-ha-1-año-1, valor intermedio a los registrados en otros bosques secos tropicales. Se evidenció una correlación significativa entre la caída de hojarasca y la precipitación. Los aportes orgánicos fueron dominados por la fracción foliar (66,61 %), seguidos del material reproductivo (15,92 %), el material leñoso (11,12 %) y misceláneo (6,36 %). La mayor caída de hojarasca foliar se registró para Prosopisjuliflora (1,31 t-ha-1-año1) y la menor caída la presentó Brosimum alicastrum (0,46 t-ha^-año1). Las especies P. juliflora y Anacardium excelsum presentaron los mayores aportes de hojarasca foliar, lo que sugiere que podrían ser especies potenciales para su inclusión en actividades de restauración de zonas con corrientes de agua. P. juliflora fue la especie que presentó mayores tasas de descomposición de hojarasca (0,242 año-1), mientras que la Sterculia apetala fue la más persistente (0,079 año1). Los resultados indican que la caída de hojarasca está condicionada por la composición del bosque y las variaciones climáticas.


ABSTRACT We analyzed the contribution of particulate organic matter to the spring Cañaverales (La Guajira, Colombia) over a period of six months (dry and rainy). The monthly litterfall was 0.17 t-ha-1-month-1, which represented 2.08 t-ha-1-year-1 when extrapolated to one year. This is an intermediate value with respect to others reported from tropical dry forests. The correlation between litter production and precipitation was statistically significant. Litterfall was dominated by the leaf fraction (66.61 %), followed by the reproductive material (15.92 %), the woody (11.12 %) and miscellaneous materials (6.36 %). The highest production of leaf litter was registered for Prosopis juliflora (1.31 t-ha-1 year1) and the lowest for Brosimum alicastrum (0.46 t-ha^year1). P. juliflora and Anacardium excelsum, presented the major contributions of foliar leaf litter, what suggests they could be potential species for inclusion in restoration activities in riparian areas. P. juliflora was the species that presented the highest rates of litter decomposition (0.242 year1), while the Sterculia apetala was the most persistent (0.079 year-1). The results indicate that litterfall and litter decomposition rates depend on forest composition and climatic variations.

15.
rev. udca actual. divulg. cient ; 20(2): 435-444, jul.-dic. 2017. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1094692

RESUMO

La presencia de metales pesados, como el plomo (Pb+2), en los cuerpos de agua genera alteraciones sobre la calidad ambiental y la salud pública, debido a su solubilidad y su capacidad de acumulación en la cadena trófica, problemática que se puede incrementar por la acumulación de Eichhornia crassipes, una maleza acuática con alta capacidad invasora, cuya presencia en los ecosistemas acuáticos favorece los procesos de eutrofización y crecimiento de microorganismos patógenos, vectores de enfermedades. Como alternativa para la eliminación de metales pesados y el aprovechamiento de tallos TEC y hojas HEC de E. crassipes, se evaluó la capacidad de adsorción y de eficiencia de remoción de Pb+2 en solución acuosa, de dicha biomasa. Inicialmente, se realizaron ensayos batch, para analizar la influencia de la dosis de adsorbente, tiempo de contacto y pH de la solución. Como método de disposición final, se analizó la calcinación, a temperaturas de 700 y 800°C. Los datos experimentales de equilibrio fueron correlacionados, utilizando los modelos de Langmuir y Freundlich. El modelo que mejor se ajustó fue el de Langmuir, con R² = 0,9816 TEC y R² = 0,9854 HEC, lográndose una máxima capacidad de adsorción de 172,41mg/g TEC y 131,58mg/g HEC, con 0,2g de biomasa/200mL, pH 5,5 y 3h de contacto. En todos los ensayos, se lograron remociones de Pb+2 superiores al 97%. Los ensayos de calcinación indican que, a temperaturas ≥800°C, es posible estabilizar la biomasa residual, impidiendo que los cationes metálicos removidos sean liberados de la matriz biológica, por efectos de soluciones lixiviantes de bajo pH.


The presence of heavy metals such as lead (Pb+2) in water bodies causes alterations in environmental quality and public health due to their solubility and capacity of accumulation in the food chain. Problems that can be increased by the accumulation of Eichhornia crassipes an aquatic weed with high invasive capacity whose presence in the aquatic ecosystems favors the processes of eutrophication and growth of pathogenic microorganisms vectors of diseases. As an alternative for the removal of heavy metals and the use of TEC stems and HEC leaves of E. crassipes, the adsorption capacity and removal efficiency of Pb+2 in aqueous solution of this biomass were evaluated. Initially batch tests were performed to analyze the influence of the adsorbent dose, contact time and solution pH. As final disposal method, the calcination was analyzed at temperatures of 700 and 800°C. The equilibrium experimental data were correlated using the Langmuir and Freundlich models. The best fit model was the Langmuir model with R²=0.9816 TEC and R²=0.9854 HEC, achieving a maximum adsorption capacity of 172.41mg/g TEC and 131.58mg/g HEC with 0.2 g Of biomass/200mL, pH 5.5 and 3h of contact. Pb+2 removals above 97% were achieved in all tests. Calcination tests indicate that at temperatures ≥800°C it is possible to stabilize the residual biomass by preventing the removed metal cations from being released from the biological matrix by the effects of low pH leaching solutions.

16.
Zootaxa ; 4175(4): 377-389, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27811749

RESUMO

A reference 535 bp barcode sequence from a fragment of the mitochondrial gene cytochrome oxidase I (COI), acquired from specimens of An. neivai Howard, Dyar & Knab, 1913 from its type locality in Panama, was used as a tool for distinguishing this species from others in the subgenus Kerteszia. Comparisons with corresponding regions of COI between An. neivai and other species in the subgenus (An. bellator Dyar & Knab 1906, An. homunculus Komp 1937, An cruzii Dyar & Knab, 1908 and An. laneanus Corrêa & Cerqueira, 1944) produced K2P genetic distances of 8.3-12.6%, values well above those associated with intraspecific variation. In contrast, genetic distances among 55 specimens from five municipalities in the Colombian Pacific coastal state of Chocó were all within the range of 0-2.5%, with an optimized barcode threshold of 1.3%, the limit for unambiguous differentiation of An. neivai. Among specimens from the Chocó region, 18 haplotypes were detected, two of which were widely distributed over the municipalities sampled. The barcode sequence permits discrimination of An. neivai from sympatric species and indicates genetic variability within the species; aspects key to malaria surveillance and control as well as defining geographic distribution and dispersion patterns.


Assuntos
Anopheles/genética , Código de Barras de DNA Taxonômico , Malária Falciparum/transmissão , Animais , Anopheles/parasitologia , Colômbia , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Variação Genética/genética , Masculino , Plasmodium falciparum
17.
Rev. estomat. salud ; 24(1): 18-23, 20160000.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-878295

RESUMO

Introducción: El sistema cráneo-cervico- mandibular necesita de factores genéticos, ambientales y funcionales para su desarro- llo. La ausencia de estímulos funcionales genera alteración en el crecimiento y mal oclusiones. Objetivo: Evaluar los cambios en las di- mensiones de los arcos en pacientes con dentición primaria y mordida profunda entre 3 y 5 años, como resultado del trata - miento temprano con ortopedia funcional. Materiales y Métodos: Muestra de 20 niños, entre 3 y 5 años de edad, con denti - ción decidua completa, mordida profunda, arcos estrechos y relación molar con plano terminal recto o escalón distal, que acudie - ron a la Universidad del Valle. Se midió en modelos en yeso: Longitud, ancho interca - nino, ancho intermolar, perímetro, overbite y overjet. Posteriormente a todos los pa- cientes se les colocaron pistas directas de Planas elaboradas de forma indirecta, se les realizó desgaste selectivo y reorientación masticatoria. Pasados 6 meses de tratamien - to se realizaron las segundas mediciones. Resultados: En promedio el Overbite inicial de los participantes fue de 87,95%. Se encontró que el Overbite final de los pacientes fue en promedio del 25%. Se encontró diferencias entre los dos tiempos de medición para todas las variables, aun- que para el perímetro superior no fueron estadísticamente significativas. La longitud superior y el ancho intermolar tuvieron el mayor porcentaje de cambio. Conclusiones: Las pistas directas de Planas contribuyen a cambios significativos en las dimensiones de los arcos dentales, cuando se implementa como tratamiento temprano para la mordida profunda y/o distoclusión en la dentición decidua...(Au)


Introduction: The skull cervico mandibu - lar system needs of genetic, environmental and functional factors for development. The absence of funcionals stimuli gene - rate change in growth and malocclusions. Objective: To evaluate the changes in the dimensions of the archs in patients with primary dentition and deep bite between 3 and 5 years, as a result of early treatment with functional orthopedic. Materials and Methods: Sample 20 chil- dren, between 3 and 5 years old, with com- plete primary dentition, deep bite, narrow arches, molar ratio straight terminal plane or distal step, who attended the Universi- dad del Valle. It was measured in plaster casts: Length, width intercanine, intermo - lar width, perimeter, overbite and overjet. Subsequently all patients were placed Pla- nas direct Tracks elaborate indirectly, He underwent selective grinding and chewing orientation. After 6 months of treatment the second measurements were made. Results: The average initial overbite of the participants was 87.95%. It was found that the final overbite of patients was in average 25%. Differences between the two measurement times for all variables was found, although the upper perimeter were not statistically significant. The upper length and width intermolar had the highest percentage of change. Conclusions: Direct Planas tracks con - tributing to significant changes in the dimensions of the dental arches, when it implemented as early treatment for deep bite and/or distoclusion in the primary dentition.


Assuntos
Odontologia , Má Oclusão , Arco Dental , Maxila , Ortopedia , Odontopediatria
18.
Acta biol. colomb ; 17(1): 51-66, Jan.-Apr. 2012. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-649938

RESUMO

En tres formaciones vegetales representativos de la ribera del río Gaira, (bosque muy húmedo subtropical (bmh-ST), bosque húmedo subtropical (bh-ST) y monte espinoso tropical (me-T)), fueron medidos durante un período de seis meses (lluvioso y seco) los flujos de los nutrientes nitrógeno (N) y fósforo (P) a través de la hojarasca. Las concentraciones de estos nutrientes fueron semejantes en las tres formaciones vegetales (1,71% N y 0,12% P para el bh-ST; seguidos por el me-T con 1,50% N y 0,10% P y el bmh-ST con 1,39% N y 0,08% P), presentándose las diferencias más notorias para N, siendo el bh-ST establecidos en el tramo medio de la cuenca el que presentó las concentraciones más elevadas. Los mayores retornos de biomasa y nutrientes se presentaron en el bh-ST y el me-T establecidos en el tramo medio y bajo de la cuenca. La hojarasca mostró alta concentración de N y consecuentemente, dados los altos valores de producción de las diferentes fracciones, un retorno potencial alto de N ( 78,6 kg ha-1 año-1). P presentó una concentración foliar con un retorno potencial de 4,9 kgha1año-1y altos valores en los índices de eficiencia de uso (IEV: 2888,5) y la reabsorción foliar (ERN: 98,2), fue el nutriente más limitante.


In three representative forests along the river Gaira, (subtropical wet forest, subtropical moist forest and tropical thorn mount), were measured over six months (wet and dry seasons) fluxes of nitrogen and phosphorus through the litter. Concentrations of nutrients (nitrogen and phosphorus) in the litter were relatively similar in the three Nevada de Santa Marta Colombia. Fuentes, Rodríguez. vegetation types (1.71% N and 0.12% P for the subtropical moist forest, followed by the tropical thorn mount with 1.50% N and 0.10% P and the subtropical wet forest with 1.39% N and 0.08% P), with the most significant differences found for nitrogen, which is the major nutrient with the absolute maximum in the subtropical rain forest set in the middle stretch of the basin. The greatest returns on biomass and nutrients occurred in the subtropical moist forest and tropical thorn mount set in the middle and lower reaches of the basin. The leaves showed high concentration of N and consequently, given the high production values of the different fractions, a high potential return of N ( 78.6 kg ha-1 yr-1). The foliar P concentration showed a potential return of 4.9 kgha1año-1 and high values of the indices of efficiency in their use (IEV:2888.5) and foliar resorption (ERN: 98.2), was the nutrient most limiting.

19.
Am J Public Health ; 101(6): 1024-31, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21493932

RESUMO

Throughout the 20th century, US public health and immigration policies intersected with and informed one another in the country's response to Mexican immigration. Three historical episodes illustrate how perceived racial differences influenced disease diagnosis: a 1916 typhus outbreak, the midcentury Bracero Program, and medical deportations that are taking place today. Disease, or just the threat of it, marked Mexicans as foreign, just as much as phenotype, native language, accent, or clothing. A focus on race rendered other factors and structures, such as poor working conditions or structural inequalities in health care, invisible. This attitude had long-term effects on immigration policy, as well as on how Mexicans were received in the United States.


Assuntos
Emigração e Imigração/história , Prática de Saúde Pública/história , Política Pública/história , Emigração e Imigração/legislação & jurisprudência , Emprego/história , Disparidades nos Níveis de Saúde , História do Século XX , Humanos , México/etnologia , Preconceito , Estados Unidos
20.
Arch. pediatr. Urug ; 80(4): 269-275, 2009. tab
Artigo em Espanhol | LILACS | ID: lil-588059

RESUMO

El paro cardiorrespiratorio en niños es un evento clínico de poca frecuencia pero de alto riesgo, por lo que la formación del posgrado en reanimación cardiopulmonar (RCP) es un aspecto prioritario. Objetivo: describir el grado de formación en RCP de los posgrados y residentes de pediatría y vincularlo con el año curricular y su actividad laboral. Material y método: estudio descriptivo, transversal, a través de una encuesta personal, anónima y presenciada a posgrados y residentes de pediatría. El formulario contenía ocho preguntas de tipo múltiple opción. Fueron indagados aspectos de RCP básica y avanzada. Se autoevaluó además el grado de seguridad y formación sobre RCP pediátrica así como el tipo de actividad laboral que desempeñaban. Los datos fueron analizados con el programa EPI-INFO 2002. Resultados: fueron encuestados 106 médicos. El 5,7% de los encuestados obtuvo más de 80% de respuestas correctas. No se observaron diferencias estadísticamente significativas entre la calidad de las repuestas cuando fue correlacionada con el año en curso y con la realización previa de cursos de RCP. El 34,9% de los encuestados trabaja en puestos fijos de emergencia o en urgencias prehospitalarias. Conclusión: el grado de conocimiento y entrenamiento en RCP de los pediatras en formación está muy lejos de ser satisfactorio. Frente a los resultados obtenidos es fundamental enfatizar en la formación teórico-práctica sobre RCP durante el curso del posgrado de pediatría.


Cardiac respiratory arrest in children is an unfrequent clinical event but of high risk, for that reason, getting a postgraduate qualification in cardiopulmonary resuscitation (CPR) is a priority. Objective: evaluate the level of pediatrics postgraduates and residents regarding CPR, and relate it to the curricular year and work activity.Material and method: transverse descriptive study through a personal, anonymous survey to pediatrics postgraduates and residents. The form had 8 multiple choice questions; the topics were CPR basic and advanced. There was also a self-evaluation on training on pediatrics CPR, it’s level of safety, and the kind of working activity developed. The data was analized with the program EPI-INFO 2002. Results: 106 doctors were polled. 5,7% got more than 80% correct answers. There were no meaningful statistic differences in the quality of the answers when correlated to the year of training and the fact of having assisted to CPR courses. 34,9% of those polled work permanently in emergency or prehospital emergencies. Conclusion: the amount of knowledge and training when it comes to CPR in future pediatrics is far from the desired. Considering the results obtained it is necessary to emphasize the CPR theory practice training during the pediatrics postgraduate course.


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Educação de Pós-Graduação , Avaliação de Recursos Humanos em Saúde , Reanimação Cardiopulmonar/educação , Reanimação Cardiopulmonar/métodos , Desenvolvimento de Pessoal , Capacitação de Recursos Humanos em Saúde
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