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1.
BJS Open ; 3(5): 722-732, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31592517

RESUMEN

Background: Emergency and essential surgical, obstetric and anaesthesia (SOA) care are now recognized components of universal health coverage, necessary for a functional health system. To improve surgical care at a national level, strategic planning addressing the six domains of a surgical system is needed. This paper details a process for development of a national surgical, obstetric and anaesthesia plan (NSOAP) based on the experiences of frontline providers, Ministry of Health officials, WHO leaders, and consultants. Methods: Development of a NSOAP involves eight key steps: Ministry support and ownership; situation analysis and baseline assessments; stakeholder engagement and priority setting; drafting and validation; monitoring and evaluation; costing; governance; and implementation. Drafting a NSOAP involves defining the current gaps in care, synthesizing and prioritizing solutions, and providing an implementation and monitoring plan with a projected cost for the six domains of a surgical system: infrastructure, service delivery, workforce, information management, finance and governance. Results: To date, four countries have completed NSOAPs and 23 more have committed to development. Lessons learned from these previous NSOAP processes are described in detail. Conclusion: There is global movement to address the burden of surgical disease, improving quality and access to SOA care. The development of a strategic plan to address gaps across the SOA system systematically is a critical first step to ensuring countrywide scale-up of surgical system-strengthening activities.


Antecedentes: En la actualidad, se reconoce que la atención quirúrgica, obstétrica y anestésica urgente y esencial (surgical, obstetric, and anaesthesia, SOA) es uno de los componentes de la cobertura sanitaria universal y un elemento necesario para el funcionamiento de un sistema de salud. Para mejorar la atención quirúrgica a nivel nacional, se necesita una planificación estratégica que aborde los seis dominios de un sistema quirúrgico. En este artículo, se detalla el proceso para el desarrollo de un plan nacional de cirugía, obstetricia y anestesia (national surgical, obstetric, and anaesthesia plan, NSOAP) basado en las experiencias de los principales proveedores, los funcionarios del Ministerio de Salud, los líderes de la Organización Mundial de la Salud y consultores. Métodos: El desarrollo de un NSOAP incluye ocho pasos clave: (1) apoyo y dependencia del ministerio, (2) análisis de la situación y evaluaciones de referencia, (3) compromiso de los agentes implicados y establecimiento de prioridades, (4) redacción y validación, (5) seguimiento y evaluación, (6) análisis de costes, (7) gobernanza y (8) implementación. Redactar un NSOAP implica definir los déficits actuales en la atención, sintetizar y priorizar soluciones, y proporcionar un plan de implementación y seguimiento con unos costes proyectados para los seis dominios de un sistema quirúrgico: infraestructura, prestación de servicios, personal, gestión de la información, finanzas y gobernanza. Resultados: Hasta la fecha, cuatro países han completado un NSOAP y 23 más se han comprometido con su desarrollo. Las lecciones aprendidas de estos procesos previos de NSOAP se describen con detalle. Conclusiones: Existe un movimiento global para abordar la carga de las enfermedades que precisan cirugía, mejorar la calidad y el acceso a la atención SOA. El desarrollo de un plan estratégico para la aproximación sistemáticamente los déficits en todo el sistema SOA es un primer paso crítico para garantizar la ampliación a nivel nacional de las actividades de fortalecimiento del sistema quirúrgico.


Asunto(s)
Anestesia/métodos , Servicios Médicos de Urgencia/normas , Obstetricia/organización & administración , Procedimientos Quirúrgicos Operativos/métodos , Anestesia/economía , Anestesia/normas , Atención a la Salud/economía , Atención a la Salud/organización & administración , Femenino , Implementación de Plan de Salud/métodos , Fuerza Laboral en Salud/organización & administración , Humanos , Gestión de la Información , Liderazgo , Programas Nacionales de Salud/organización & administración , Obstetricia/economía , Obstetricia/normas , Participación de los Interesados , Procedimientos Quirúrgicos Operativos/economía , Procedimientos Quirúrgicos Operativos/normas , Atención de Salud Universal , Organización Mundial de la Salud/economía , Organización Mundial de la Salud/organización & administración
2.
J Public Health (Oxf) ; 40(4): 813-819, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29385489

RESUMEN

Background: Local authorities (LAs) have statutory responsibility to reduce health inequalities and improve public health. Place-based approaches may positively influence service provision yet little is known about their implementation and potential for reducing inequality through health and wellbeing improvements. An English LA implemented a place-based working (PBW) pilot in a small geography during austerity measures in the north of England. This involved three strands (early intervention, estate services and community intelligence) which were introduced separately and covered overlapping geographies. Predominantly focusing on early intervention, this qualitative study investigates stakeholders' perceptions of the pilot and its potential to improve health and wellbeing by reducing inequality. Methods: In total, 15 face-to-face qualitative interviews with stakeholders were completed. Thematic analysis produced context, mechanism and outcome configurations in a process adapted from realist evaluation methodology. Results: Stakeholders described PBW as holistic, upstream and cutting across departmental boundaries to engage staff and the community. Collaborative working was considered important and was aided by PBW in our study. Conclusions: PBW has the potential to reduce health inequalities by improving health and wellbeing. LAs deliver services that affect health and wellbeing and PBW may help develop a more coordinated response to improve outcomes and potentially save money.


Asunto(s)
Disparidades en el Estado de Salud , Práctica de Salud Pública , Servicios de Salud Comunitaria/métodos , Servicios de Salud Comunitaria/organización & administración , Participación de la Comunidad/métodos , Inglaterra , Humanos , Entrevistas como Asunto , Gobierno Local , Desarrollo de Programa , Investigación Cualitativa
3.
Am J Physiol Gastrointest Liver Physiol ; 304(5): G516-26, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23275617

RESUMEN

Pancreatic acinar cells express proteinase-activated receptor-2 (PAR2) that is activated by trypsin-like serine proteases and has been shown to exert model-specific effects on the severity of experimental pancreatitis, i.e., PAR2(-/-) mice are protected from experimental acute biliary pancreatitis but develop more severe secretagogue-induced pancreatitis. P2pal-18S is a novel pepducin lipopeptide that targets and inhibits PAR2. In studies monitoring PAR2-stimulated intracellular Ca(2+) concentration changes, we show that P2pal-18S is a full PAR2 inhibitor in acinar cells. Our in vivo studies show that P2pal-18S significantly reduces the severity of experimental biliary pancreatitis induced by retrograde intraductal bile acid infusion, which mimics injury induced by endoscopic retrograde cholangiopancreatography (ERCP). This reduction in pancreatitis severity is observed when the pepducin is given before or 2 h after bile acid infusion but not when it is given 5 h after bile acid infusion. Conversely, P2pal-18S increases the severity of secretagogue-induced pancreatitis. In vitro studies indicate that P2pal-18S protects acinar cells against bile acid-induced injury/death, but it does not alter bile acid-induced intracellular zymogen activation. These studies are the first to report the effects of an effective PAR2 pharmacological inhibitor on pancreatic acinar cells and on the severity of experimental pancreatitis. They raise the possibility that a pepducin such as P2pal-18S might prove useful in the clinical management of patients at risk for developing severe biliary pancreatitis such as occurs following ERCP.


Asunto(s)
Enfermedades de las Vías Biliares/prevención & control , Lipopéptidos/farmacología , Pancreatitis/prevención & control , Receptor PAR-2/antagonistas & inhibidores , Células Acinares/efectos de los fármacos , Animales , Ácidos y Sales Biliares/metabolismo , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Ceruletida/farmacología , Colangiopancreatografia Retrógrada Endoscópica , Quimotripsinógeno/metabolismo , Colorantes , Activación Enzimática/efectos de los fármacos , Precursores Enzimáticos/metabolismo , Cálculos Biliares/prevención & control , Indicadores y Reactivos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Propidio , Tripsinógeno/metabolismo
4.
J Fish Biol ; 78(1): 166-82, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21235553

RESUMEN

Southern garfish Hyporhamphus melanochir were examined for metazoan parasites from nine sites in three regions (Spencer Gulf, Gulf St Vincent and northern Kangaroo Island) in South Australia to document parasite assemblages, identify candidate species suitable for use as biological tags and investigate spatial variation in parasite abundance. Four ectoparasite and 10 endoparasite species were identified representing Cestoda, Trematoda, Monogenea, Nematoda, Acanthocephala, Copepoda and Isopoda. Lernaeenicus hemirhamphi, Micracanthorhynchina hemirhamphi, Mothocya halei and Philometra sp. were suggested for 'permanent' biological markers. Multivariate discriminant function analysis showed that most sites could be distinguished based on differences in parasite abundance. Four endoparasites (Conohelmins sp., Hysterothylacium sp., M. hemirhamphi and Philometra sp.) were most important for site characterization. Limited spatial variation in permanent endoparasite abundance among localities in northern Spencer Gulf provided evidence for a distinct northern Spencer Gulf population with little interregional mixing. In contrast, considerable spatial variation in permanent endoparasite abundance between localities sampled off Kangaroo Island implied limited local movement and suggested H. melanochir may comprise a metapopulation structure. These results largely align with recent evidence from otolith chemistry that indicates fine-scale geographical population structuring in South Australian waters.


Asunto(s)
Biodiversidad , Peces/parasitología , Geografía , Animales , Biomarcadores , Femenino , Masculino , Australia del Sur
5.
Diabetologia ; 50(4): 764-73, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17318626

RESUMEN

AIMS/HYPOTHESIS: Pancreatic islets have evolved remarkable, though poorly understood mechanisms to modify beta cell mass when nutrient intake fluctuates or cells are damaged. We hypothesised that appropriate and timely adjustments in cell number occur because beta cells release proliferative signals to surrounding cells when stimulated by nutrients and 'bleed' these growth factors upon injury. MATERIALS AND METHODS: In rat pancreatic islets, we measured DNA content, insulin content, insulin secretion after treatment, immunoblots of apoptotic proteins and the uptake of nucleoside analogues to assess the ability of gamma-aminobutyric acid (GABA), which is highly concentrated in beta cells, to act as a growth and survival factor. This focus is supported by work from others demonstrating that GABA increases cell proliferation in the developing nervous system, acts as a survival factor for differentiated neurons and, interestingly, protects plants under stress. RESULTS: Our results show that DNA, insulin content and insulin secretion are higher in freshly isolated islets treated with GABA or GABA B receptor agonists. Exposure to GABA upregulated the anti-apoptotic protein B-cell chronic lymphocytic leukaemia XL and limited activation of caspase 3 in islets. The cellular proliferation rate in GABA-treated islets was twice that of untreated controls. CONCLUSIONS/INTERPRETATION: We conclude that GABA serves diverse purposes in the islet, meeting a number of functional criteria to act as an endogenous co-regulator of beta cell mass.


Asunto(s)
Células Secretoras de Insulina/patología , Ácido gamma-Aminobutírico/metabolismo , Animales , Proliferación Celular , Supervivencia Celular , ADN/metabolismo , Inmunohistoquímica , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Masculino , Microscopía Confocal , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/metabolismo , Receptores de GABA-B/metabolismo , Timidina/química , Regulación hacia Arriba
6.
Parasitology ; 133(Pt 4): 477-83, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16817996

RESUMEN

The size and fecundity of parasitic nematodes are constrained by the host immune response. For the parasitic nematode of rats, Strongyloides ratti, parasitic females infecting immunized rats are smaller and less fecund than those infecting naïve rats. Here, we investigated whether these constraints on size and fecundity are life-long. This was done by comparison of worms from different immunization and immunosuppression regimes. It was found that the per capita fecundity of parasitic females of S. ratti is fully reversed, but that their size is only partially reversed, if previously immunized hosts are subsequently immunosuppressed, suggesting that fecundity is not subject to life-long constraints. The host immune response also resulted in allometric changes in the parasitic females. The significance of these results with respect to the growth and control of nematode fecundity are discussed.


Asunto(s)
Inmunización/veterinaria , Strongyloides ratti/fisiología , Estrongiloidiasis/inmunología , Estrongiloidiasis/parasitología , Animales , Femenino , Fertilidad/fisiología , Interacciones Huésped-Parásitos/inmunología , Inmunosupresores/farmacología , Masculino , Ratas , Strongyloides ratti/anatomía & histología , Strongyloides ratti/crecimiento & desarrollo , Factores de Tiempo
7.
Am J Physiol Gastrointest Liver Physiol ; 289(4): G713-21, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15920015

RESUMEN

Supramaximal stimulation of the rat pancreas with CCK, or its analog caerulein, triggers acute pancreatitis and a number of pancreatitis-associated acinar cell changes including intracellular activation of digestive enzyme zymogens and acinar cell injury. It is generally believed that some of these various acinar cell responses to supramaximal secretagogue stimulation are interrelated and interdependent. In a recent report, Lu et al. showed that secretin, by causing generation of cAMP and activation of PKA, sensitizes acinar cells to secretagogue-induced zymogen activation, and, as a result, submaximally stimulating concentrations of caerulein can, in the presence of secretin, trigger intracellular zymogen activation. We found that secretin also sensitizes acinar cells to secretagogue-induced cell injury and to subapical F-actin redistribution but that it did not alter the caerulein concentration dependence of other pancreatitis-associated changes such as the induction of a peak plateau intracellular [Ca(2+)] rise, inhibition of secretion, activation of ERK1/2, and activation of NF-kappaB. The finding that secretin sensitizes acinar cells to both intracellular zymogen activation and cell injury is consistent with the concept that these two early events in pancreatitis are closely interrelated and, possibly, interdependent. On the other hand, the finding that, in the presence of secretin, caerulein can trigger subapical F-actin redistribution without inhibiting secretion challenges the concept that disruption of the subapical F-actin web is causally related to high-dose secretagogue-induced inhibition of secretion in pancreatic acinar cells.


Asunto(s)
Ceruletida/farmacología , Páncreas/efectos de los fármacos , Secretina/farmacología , Actinas/metabolismo , Amilasas/antagonistas & inhibidores , Amilasas/metabolismo , Animales , Muerte Celular/efectos de los fármacos , AMP Cíclico/fisiología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Precursores Enzimáticos/farmacología , Isoquinolinas/farmacología , MAP Quinasa Quinasa 2/fisiología , Masculino , Proteína Quinasa 1 Activada por Mitógenos/fisiología , FN-kappa B/fisiología , Ratas , Ratas Sprague-Dawley , Estimulación Química , Sulfonamidas/farmacología
8.
Gut ; 54(10): 1461-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15870229

RESUMEN

BACKGROUND AND AIMS: The majority of patients with chronic pancreatitis are alcoholics. Our goal was to develop a mouse model of alcohol dependent chronic pancreatitis. METHODS: Mice were fed either the non-alcohol containing Lieber-DeCarli diet or the Lieber-DeCarli diet containing 24% of calories as ethanol. After eight weeks and while on their respective diets, mice were subjected to repeated episodes of acute pancreatitis elicited by administration of caerulein. They were sacrificed 1, 3, and 5 weeks after the last dose of caerulein. Pancreatic morphology and collagen deposition were evaluated in samples stained with haematoxylin-eosin and Sirius red. Collagen content was quantitated by measuring OH-proline. Gene expression was determined by quantitative polymerase chain reaction. RESULTS: Both groups of mice gained weight at the same rate. Those receiving the alcohol containing diet had serum alcohol levels of approximately 100 mM. No histological or gene expression differences were found in mice that were not subjected to acute pancreatitis, regardless of their diet. Necrosis, Sirius red staining, OH-proline content, and expression of alpha-1 collagen I, alpha-smooth muscle actin, transforming growth factor beta1, and tissue inhibitor of metalloproteinase 1 were all increased in mice fed the alcohol containing diet and given caerulein compared with those fed the control diet and given caerulein. Matrix metalloproteinase 9 expression was transiently decreased in mice fed ethanol and given caerulein compared with the group given caerulein but not fed ethanol. CONCLUSION: We have developed a mouse model of alcohol dependent chronic pancreatic fibrosis. This mouse model may be useful in studies examining the effects of genetic manipulation on chronic pancreatitis.


Asunto(s)
Modelos Animales de Enfermedad , Etanol , Pancreatitis/inducido químicamente , Animales , Ceruletida/administración & dosificación , Enfermedad Crónica , Colágeno/análisis , Dieta , Etanol/administración & dosificación , Etanol/sangre , Fibrosis/genética , Regulación de la Expresión Génica , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Endogámicos C3H , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Páncreas/patología , Pancreatitis/sangre , Pancreatitis/fisiopatología , Aumento de Peso/fisiología
9.
Phys Rev Lett ; 93(5): 057401, 2004 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-15323729

RESUMEN

The temperature dependence of spin coherence in InGaAs quantum dots is obtained from quantum beats observed in polarization-resolved pump-probe experiments. Within the same sample we clearly distinguish between coherent spin dynamics leading to quantum beats and incoherent long-lived spin-memory effects. Analysis of the coherent data using a theoretical model reveals approximately 10 times greater stability of the spin coherence at high temperature compared to that found previously for exciton states in four-wave-mixing experiments by Borri et al. [Phys. Rev. Lett. 87, 157401 (2001)]]. The data on incoherent polarization reveal a new form of spin memory based on charged quantum dots.

10.
Gut ; 50(1): 78-83, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11772971

RESUMEN

BACKGROUND AND AIM: Recent studies have indicated that prior thermal stress causes upregulation of heat shock protein 70 (HSP70) expression in the pancreas and protects against secretagogue induced pancreatitis. The mechanisms responsible for the protective effect are not known. Similarly, the effects of prior non-thermal stress on HSP70 expression and pancreatitis are not known. The current studies were designed to specifically address these issues. METHODS: In the current studies pancreatitis was induced by administration of a supramaximally stimulating dose of caerulein 12 hours after thermal stress and 24 hours after non-thermal (that is, beta adrenergic stimulation) stress. RESULTS: Both thermal and non-thermal stresses caused pancreatic HSP70 levels to rise and resulted in increased expression of HSP70 in acinar cells. Both forms of stresses protected against caerulein induced pancreatitis and prevented the early intrapancreatic activation of trypsinogen which occurs in this model of pancreatitis. CONCLUSIONS: These results suggest that both thermal and non-thermal stresses protect against pancreatitis by preventing intrapancreatic digestive enzyme activation and that HSP70 may mediate this protective effect.


Asunto(s)
Hipertermia Inducida/métodos , Pancreatitis/enzimología , Estrés Fisiológico/fisiopatología , Tripsinógeno/fisiología , Amilasas/fisiología , Análisis de Varianza , Animales , Western Blotting , Ceruletida , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Proteínas HSP70 de Choque Térmico/fisiología , Mediciones Luminiscentes , Masculino , Pancreatitis/inducido químicamente , Peroxidasa/fisiología , Ratas , Ratas Wistar
11.
Protoplasma ; 215(1-4): 140-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11732053

RESUMEN

In this review we integrate the information available on the cell biology of root hair formation with recent findings from the analysis of root hair mutants of Arabidopsis thaliana. The mature Arabidopsis root epidermis consists of root-hair-producing cells and non-root-hair-producing cells. Root hair growth begins with a swelling of the outer epidermal wall. It has been postulated that this is due to a pH-mediated localised cell wall loosening. From the bulge a single root hair emerges which grows by tip growth. The root hair tip consists of a vesicle-rich zone and an organelle-rich subapical zone. The vesicles supply new plasma membrane and cell wall material for elongation. The cytoskeleton and its associated regulatory proteins such as profilin and spectrin are proposed to be involved in the targeting of vesicles. Ca2+ influxes and gradients are present in hair tips, but their function is still unclear. Mutants have been isolated with lesions in various parts of the root hair developmental pathway from bulge identity and initiation to control of tip diameter and extent and polarity of elongation.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Raíces de Plantas/crecimiento & desarrollo , Actinas/metabolismo , Citoesqueleto/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Iones/metabolismo , Proteínas de Microfilamentos/metabolismo , Microtúbulos/metabolismo , Modelos Biológicos , Fenotipo , Proteínas de Plantas/metabolismo , Raíces de Plantas/ultraestructura , Transporte de Proteínas/fisiología
12.
J Clin Invest ; 108(9): 1387-95, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11696584

RESUMEN

Intra-acinar cell activation of digestive enzyme zymogens including trypsinogen is generally believed to be an early and critical event in acute pancreatitis. We have found that the phosphatidylinositol 3-kinase inhibitor wortmannin can reduce the intrapancreatic activation of trypsinogen that occurs during two dissimilar experimental models of rodent acute pancreatitis, secretagogue- and duct injection-induced pancreatitis. The severity of both models was also reduced by wortmannin administration. In contrast, the NF-kappa B activation that occurs during the early stages of secretagogue-induced pancreatitis is not altered by administration of wortmannin. Ex vivo, caerulein-induced trypsinogen activation is inhibited by wortmannin and LY294002. However, the cytoskeletal changes induced by caerulein were not affected by wortmannin. Concentrations of caerulein that induced ex vivo trypsinogen activation do not significantly increase phosphatidylinositol-3,4-bisphosphate or phosphatidylinositol 3,4,5-trisphosphate levels or induce phosphorylation of Akt/PKB, suggesting that class I phosphatidylinositol 3-kinases are not involved. The concentration of wortmannin that inhibits trypsinogen activation causes a 75% decrease in phosphatidylinositol 3-phosphate, which is implicated in vesicle trafficking and fusion. We conclude that a wortmannin-inhibitable phosphatidylinositol 3-kinase is necessary for intrapancreatic activation of trypsinogen and regulating the severity of acute pancreatitis. Our observations suggest that phosphatidylinositol 3-kinase inhibition might be of benefit in preventing acute pancreatitis.


Asunto(s)
Pancreatitis/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/fisiología , Tripsinógeno/metabolismo , Enfermedad Aguda , Androstadienos/farmacología , Animales , Células Cultivadas , Ceruletida/metabolismo , Cromonas/farmacología , Citoesqueleto/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Lisosomas/metabolismo , Masculino , Ratones , Morfolinas/farmacología , FN-kappa B/metabolismo , Necrosis , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilación , Ratas , Factores de Tiempo , Wortmanina
13.
Respir Physiol ; 128(1): 13-6, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11535257

RESUMEN

Patients with acute pancreatitis may develop acute lung injury, manifest clinically as the adult respiratory distress syndrome. Most patients who die during the early stages of severe acute pancreatitis die either with or as a result of this lung injury. To explore the events which couple acute pancreatitis to lung injury, a number of recent studies have been performed in the author's laboratory using a variety of experimental models and interventions including gene-targeted deletion of chemokines, cytokines, specific receptors, and adhesion molecules. These studies have indicated that adhesion molecules such as intracellular adhesion molecule-1 (ICAM-1), neutrophils, platelet activating factor (PAF), substance P, and chemokines acting via the CCR-1 chemokine receptor play a pro-inflammatory role while complement factor C5a plays an anti-inflammatory role in pancreatitis and lung injury. Future studies will build on these observations to expand the list of pro- and anti-inflammatory coupling factors and explore the mechanisms by which they act to cause or prevent lung injury in acute pancreatitis.


Asunto(s)
Enfermedades Pulmonares/etiología , Pancreatitis/complicaciones , Enfermedad Aguda , Animales , Complemento C5a/genética , Complemento C5a/fisiología , Modelos Animales de Enfermedad , Femenino , Humanos , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/fisiología , Ratones , Ratones Noqueados , Neutrófilos/fisiología , Factor de Activación Plaquetaria/fisiología , Ratas , Receptores CCR1 , Receptores de Quimiocina/genética , Receptores de Quimiocina/fisiología , Sustancia P/fisiología
14.
Gastroenterology ; 120(7): 1818-27, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11375962

RESUMEN

BACKGROUND & AIMS: The present study was undertaken to evaluate the role of serine proteases in regulating digestive enzyme secretion in pancreatic acinar cells. METHODS: Isolated acini were stimulated by various secretagogues in the presence or absence of cell-permeant serine protease inhibitors 4-(2-aminoethyl)-benzenesulfonyl fluoride and N(alpha)-p-tosyl-L-phenylalanine chloromethyl ketone. F-actin distribution was studied after staining with rhodamine phalloidin. RESULTS: Both cell-permeant serine protease inhibitors blocked amylase secretion in response to secretagogues that use calcium as a second messenger (e.g., cerulein, carbamylcholine, and bombesin) but not to those that use adenosine 3',5'-cyclic monophosphate (cAMP) as a second messenger (e.g., secretin and vasoactive intestinal polypeptide). Incubation of the acini with these inhibitors also resulted in a dramatic redistribution of the F-actin cytoskeleton. This redistribution was energy dependent. Similar redistribution of F-actin from the apical to the basolateral region was also observed when acini were incubated with a supramaximally stimulating concentration of cerulein, which is known to inhibit secretion. CONCLUSIONS: These results suggest that a serine protease activity is essential for maintaining the normal apical F-actin distribution; its inhibition redistributes F-actin from the apical to the basolateral region and blocks secretion induced by secretagogues that act via calcium. cAMP reverses the F-actin redistribution and hence cAMP-mediated secretion is not affected.


Asunto(s)
Actinas/metabolismo , Calcio/fisiología , Páncreas/efectos de los fármacos , Inhibidores de Serina Proteinasa/farmacología , Sulfonas/farmacología , Adenosina Trifosfato/fisiología , Animales , Bucladesina/farmacología , Calcineurina/metabolismo , Calpaína/metabolismo , Ceruletida/farmacología , AMP Cíclico/fisiología , Masculino , Páncreas/enzimología , Páncreas/ultraestructura , Proteína Quinasa C/metabolismo , Ratas , Ratas Wistar
15.
J Ultrasound Med ; 20(5): 481-90, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11345105

RESUMEN

OBJECTIVE: To compare the ability of state-of-the-art ultrasonography with that of helical computed tomography and computed tomographic angiography in detecting unresectable periampullary cancer. In most patients periampullary cancer is unresectable because of either distant metastasis or local vascular involvement. The advent of gray scale and color Doppler ultrasonography has improved the ability of ultrasonography to detect vascular involvement. METHODS: Twenty-three consecutive patients with periampullary cancer were enrolled for prospective staging of their disease by comparing helical computed tomography and computed tomographic angiography with gray scale and color Doppler ultrasonography of the abdomen. Portal vein, superior mesenteric vein, splenic vein, and superior mesenteric artery involvement was graded 0 to 4, grade 0 being no vascular involvement and grade 4 being total occlusion of the vessel. Agreement between ultrasonography and computed tomographic angiography for determining vascular involvement was measured by chi2 analysis. RESULTS: Two patients (9%) were excluded because excessive overlying bowel gas hampered the ability of ultrasonography to visualize the pancreas. For the remaining 21 patients, there was significant agreement between ultrasonography and computed tomographic angiography for detecting vascular involvement in all vessels (P < .001; portal vein, kappa = 0.67; superior mesenteric vein, kappa = 0.67; splenic vein, kappa = 0.85; and superior mesenteric artery, kappa = 0.59). Ultrasonography was in agreement with computed tomographic angiography in all cases of unresectability. Both modalities were equally poor in preoperatively showing lymphadenopathy and metastases. CONCLUSIONS: Provided that there is adequate visualization on ultrasonography of the head of the pancreas in the periampullary region, then state-of-the-art gray scale and color Doppler ultrasonography are as accurate as helical computed tomography and computed tomographic angiography for detecting the unresectability of periampullary cancer. If performed as the initial investigation and the region of the pancreatic head is clearly shown, and if vascular encasement or occlusion or distant metastasis is identified, further investigations are unnecessary.


Asunto(s)
Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Angiografía/métodos , Femenino , Humanos , Neoplasias Hepáticas/secundario , Enfermedades Linfáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/irrigación sanguínea , Neoplasias Pancreáticas/cirugía , Valor Predictivo de las Pruebas , Estudios Prospectivos , Ultrasonografía
16.
Am J Physiol Gastrointest Liver Physiol ; 280(5): G974-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11292607

RESUMEN

Complement factor C5a acting via C5a receptors (C5aR) is recognized as an anaphylotoxin and chemoattractant that exerts proinflammatory effects in many pathological states. The effects of C5a and C5aR in acute pancreatitis and in pancreatitis-associated lung injury were evaluated using genetically altered mice that either lack C5aR or do not express C5. Pancreatitis was induced by administration of 12 hourly injections of cerulein (50 microg/kg ip). The severity of pancreatitis was determined by measuring serum amylase, neutrophil sequestration in the pancreas, and acinar cell necrosis. The severity of lung injury was evaluated by measuring neutrophil sequestration in the lung and pulmonary microvascular permeability. In both strains of genetically altered mice, the severity of pancreatitis and pancreatitis-associated lung injury was greater than that noted in the comparison wild-type strains of C5aR- and C5-sufficient animals. This exacerbation of injury in the absence of C5a function indicates that, in pancreatitis, C5a exerts an anti-inflammatory effect. Potentially, C5a and its receptor are capable of both promoting and reducing the extent of acute inflammation.


Asunto(s)
Antígenos CD/fisiología , Complemento C5a/fisiología , Pulmón/fisiopatología , Pancreatitis/fisiopatología , Receptores de Complemento/fisiología , Enfermedad Aguda , Animales , Antiinflamatorios , Antígenos CD/genética , Capilares/patología , Capilares/fisiopatología , Ceruletida , Complemento C5a/deficiencia , Complemento C5a/genética , Cruzamientos Genéticos , Inflamación , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Pancreatitis/inducido químicamente , Pancreatitis/patología , Peroxidasa/análisis , Receptor de Anafilatoxina C5a , Receptores de Complemento/deficiencia , Receptores de Complemento/genética
17.
J Biol Chem ; 276(22): 18742-7, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11278554

RESUMEN

Prior stress ameliorates caerulein-induced pancreatitis in rats. NF-kappaB is a proinflammatory transcription factor activated during caerulein pancreatitis. However, the effects of prior stress on pancreatic NF-kappaB activation are unknown. In the current study, the effect of prior water immersion stress on caerulein and tumor necrosis factor-alpha (TNF-alpha)-induced NF-kappaB activation in the pancreas was evaluated. Water immersion of rats for up to 6 h prevents supramaximal caerulein-induced pancreatic IkappaB-alpha degradation and NF-kappaB activation in vivo. NF-kappaB activity is also inhibited in vitro in pancreatic acini prepared from water-immersed animals. TNF-alpha-induced NF-kappaB activation in pancreas or in pancreatic acini is unaffected by prior water immersion. Chelation of intracellular Ca(2+) by 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetate/acetoxymethyl ester has similar effects to water immersion in preventing caerulein but not TNF-alpha-induced NF-kappaB activation in pancreas. Both the spike response and the sustained rise in [Ca(2+)](i) in response to supramaximal caerulein stimulation are reduced markedly in acini prepared from water-immersed animals as compared with normal animals. Our findings indicate that, in addition to Ca(2+)-dependent mechanisms, Ca(2+)-independent signaling events also may lead to NF-kappaB activation in pancreatic acinar cells. Water immersion stress prevents supramaximal caerulein-induced NF-kappaB activation in pancreas in vivo and in vitro by affecting intracellular Ca(2+) homeostasis.


Asunto(s)
Calcio/metabolismo , Ceruletida/metabolismo , Proteínas I-kappa B , FN-kappa B/metabolismo , Páncreas/metabolismo , Agua/metabolismo , Animales , Western Blotting , Quelantes/farmacología , Citoplasma/metabolismo , Proteínas de Unión al ADN/metabolismo , Electroforesis en Gel de Poliacrilamida , Masculino , Inhibidor NF-kappaB alfa , Ratas , Ratas Wistar , Transducción de Señal , Estrés Fisiológico , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo
18.
Biochem Biophys Res Commun ; 280(1): 388-95, 2001 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-11162528

RESUMEN

Intra-acinar cell nuclear factor-kappaB (NF-kappaB) and trypsinogen activation are early events in secretagogue-induced acute pancreatitis. We have studied the relationship between NF-kappaB and trypsinogen activation in rat pancreas. CCK analogue caerulein induces early (within 15 min) parallel activation of both NF-kappaB and trypsinogen in pancreas in vivo as well as in pancreatic acini in vitro. However, NF-kappaB activation can be induced without trypsinogen activation by lipopolysaccharide in pancreas in vivo and by phorbol ester in pancreatic acini in vitro. Stimulation of acini with caerulein after 6 h of culture results in NF-kappaB but not trypsinogen activation. Protease inhibitors (AEBSF, TLCK, and E64d) inhibit both intracellular trypsin activity and NF-kappaB activation in caerulein stimulated acini. A chymotrypsin inhibitor (TPCK) inhibits NF-kappaB activation but not trypsin activity. The proteasome inhibitor MG-132 prevents caerulein-induced NF-kappaB activation but does not prevent trypsinogen activation. These findings indicate that although caerulein-induced NF-kappaB and trypsinogen activation are temporally closely related, they are independent events in pancreatic acinar cells. NF-kappaB activation per se is not required for the development of early acinar cell injury by supramaximal secretagogue stimulation.


Asunto(s)
Ceruletida/farmacología , FN-kappa B/metabolismo , Páncreas/metabolismo , Tripsinógeno/metabolismo , Animales , Células Cultivadas , Cisteína Endopeptidasas/metabolismo , ADN/metabolismo , Activación Enzimática , Cinética , Leupeptinas/farmacología , Masculino , Complejos Multienzimáticos/metabolismo , Páncreas/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal , Ratas , Ratas Wistar , Acetato de Tetradecanoilforbol/farmacología , Clorometilcetona de Tosilfenilalanila/farmacología , Tripsina/metabolismo
19.
Genes Dev ; 15(1): 79-89, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11156607

RESUMEN

The cell wall is an important determinant of plant cell form. Here we define a class of Arabidopsis root hair mutants with defective cell walls. Plants homozygous for kojak (kjk) mutations initiate root hairs that rupture at their tip soon after initiation. The KJK gene was isolated by positional cloning, and its identity was confirmed by the molecular complementation of the Kjk(-) phenotype and the sequence of three kjk mutant alleles. KOJAK encodes a cellulose synthase-like protein, AtCSLD3. KOJAK/AtCSLD3 is the first member of this subfamily of proteins to be shown to have a function in cell growth. Subcellular localization of the KOJAK/AtCSLD3 protein using a GFP fusion shows that KOJAK/AtCSLD3 is located on the endoplasmic reticulum, indicating that KOJAK/AtCSLD3 is required for the synthesis of a noncellulosic wall polysaccharide. Consistent with the cell specific defect in the roots of kjk mutants, KOJAK/AtCSDL3 is preferentially expressed in hair cells of the epidermis. The Kjk(-) phenotype and the pattern of KOJAK/AtCSLD3 expression suggest that this gene acts early in the process of root hair outgrowth. These results suggest that KOJAK/AtCSLD3 is involved in the biosynthesis of beta-glucan-containing polysaccharides that are required during root hair elongation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis/fisiología , Mutación , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/fisiología , Secuencia de Aminoácidos , Arabidopsis/citología , Arabidopsis/genética , División Celular , Clonación Molecular , Secuencia Conservada , Genes Reporteros , Prueba de Complementación Genética , Homocigoto , Datos de Secuencia Molecular , Morfogénesis , Raíces de Plantas/citología , Plantas Modificadas Genéticamente
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