Borrelia chilensis, a new member of the Borrelia burgdorferi sensu lato complex that extends the range of this genospecies in the Southern Hemisphere.

Borrelia burgdorferi sensu lato (s.l.), transmitted by Ixodes spp. ticks, is the causative agent of Lyme disease. Although Ixodes spp. ticks are distributed in both Northern and Southern Hemispheres, evidence for the presence of B. burgdorferi s.l. in South America apart from Uruguay is lacking. We now report the presence of culturable spirochetes with flat-wave morphology and borrelial DNA in endemic Ixodes stilesi ticks collected in Chile from environmental vegetation and long-tailed rice rats (Oligoryzomys longicaudatus). Cultured spirochetes and borrelial DNA in ticks were characterized by multilocus sequence typing and by sequencing five other loci (16S and 23S ribosomal genes, 5S-23S intergenic spacer, flaB, ospC). Phylogenetic analysis placed this spirochete as a new genospecies within the Lyme borreliosis group. Its plasmid profile determined by polymerase chain reaction and pulsed-field gel electrophoresis differed from that of B. burgdorferi B31A3. We propose naming this new South American member of the Lyme borreliosis group B. chilensis VA1 in honor of its country of origin.

Activation of the WNT-BMP-FGF Regulatory Network Induces the Onset of Cell Death in Anterior Mesodermal Cells to Establish the ANZ.

The spatiotemporal control of programmed cell death (PCD) plays a significant role in sculpting the limb. In the early avian limb bud, the anterior necrotic zone (ANZ) and the posterior necrotic zone are two cell death regions associated with digit number reduction. In this study, we evaluated the first events triggered by the FGF, BMP, and WNT signaling interactions to initiate cell death in the anterior margin of the limb to establish the ANZ. This study demonstrates that in a period of two to 8 h after the inhibition of WNT or FGF signaling or the activation of BMP signaling, cell death was induced in the anterior margin of the limb concomitantly with the regulation of Dkk, Fgf8, and Bmp4 expression. Comparing the gene expression profile between the ANZ and the undifferentiated zone at 22HH and 25HH and between the ANZ of 22HH and 25HH stages correlates with functional programs controlled by the regulatory network FGF, BMP, and WNT signaling in the anterior margin of the limb. This work provides novel insights to recognize a negative feedback loop between FGF8, BMP4, and DKK to control the onset of cell death in the anterior margin of the limb to the establishment of the ANZ.

Strategies for Effective Use of Genomic Information in Crop Breeding Programs Serving Africa and South Asia.

Much of the world's population growth will occur in regions where food insecurity is prevalent, with large increases in food demand projected in regions of Africa and South Asia. While improving food security in these regions will require a multi-faceted approach, improved performance of crop varieties in these regions will play a critical role. Current rates of genetic gain in breeding programs serving Africa and South Asia fall below rates achieved in other regions of the world. Given resource constraints, increased genetic gain in these regions cannot be achieved by simply expanding the size of breeding programs. New approaches to breeding are required. The Genomic Open-source Breeding informatics initiative (GOBii) and Excellence in Breeding Platform (EiB) are working with public sector breeding programs to build capacity, develop breeding strategies, and build breeding informatics capabilities to enable routine use of new technologies that can improve the efficiency of breeding programs and increase genetic gains. Simulations evaluating breeding strategies indicate cost-effective implementations of genomic selection (GS) are feasible using relatively small training sets, and proof-of-concept implementations have been validated in the International Maize and Wheat Improvement Center (CIMMYT) maize breeding program. Progress on GOBii, EiB, and implementation of GS in CIMMYT and International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) breeding programs are discussed, as well as strategies for routine implementation of GS in breeding programs serving Africa and South Asia.

Stereological Quantification of Cell-Cycle Kinetics and Mobilization of Epithelial Stem Cells during Wound Healing.

We describe a stereology method to obtain reliable estimates of the total number of proliferative and migratory epithelial cells after wounding. Using pulse and chase experiments with halogenated thymidine analogs such as iododeoxyuridine (IdU) and chlorodeoxyuridine (CldU), it is possible to track epithelial populations with heterogeneous proliferative characteristics through skin compartments. The stereological and tissue processing methods described here apply widely to address important questions of skin stem-cell biology.

Irx1 and Irx2 are coordinately expressed and regulated by retinoic acid, TGFß and FGF signaling during chick hindlimb development.

The Iroquois homeobox (Irx) genes play a crucial role in the regionalization and patterning of tissues and organs during metazoan development. The Irx1 and Irx2 gene expression pattern during hindlimb development has been investigated in different species, but its regulation during hindlimb morphogenesis has not been explored yet. The aim of this study was to evaluate the gene expression pattern of Irx1 and Irx2 as well as their regulation by important regulators of hindlimb development such as retinoic acid (RA), transforming growth factor ß (TGFß) and fibroblast growth factor (FGF) signaling during chick hindlimb development. Irx1 and Irx2 were coordinately expressed in the interdigital tissue, digital primordia, joints and in the boundary between cartilage and non-cartilage tissue. Down-regulation of Irx1 and Irx2 expression at the interdigital tissue coincided with the onset of cell death. RA was found to down-regulate their expression by a bone morphogenetic protein-independent mechanism before any evidence of cell death. Furthermore, TGFß protein regulated Irx1 and Irx2 in a stage-dependent manner at the interdigital tissue, it inhibited their expression when it was administered to the interdigital tissue at developing stages before their normal down-regulation. TGFß administered to the interdigital tissue at developing stages after normal down-regulation of Irx1 and Irx2 evidenced that expression of these genes marked the boundary between cartilage tissue and non-cartilage tissue. It was also found that at early stages of hindlimb development FGF signaling inhibited the expression of Irx2. In conclusion, the present study demonstrates that Irx1 and Irx2 are coordinately expressed and regulated during chick embryo hindlimb development as occurs in other species of vertebrates supporting the notion that the genomic architecture of Irx clusters is conserved in vertebrates.

Modulatory role of sensory innervation on hair follicle stem cell progeny during wound healing of the rat skin.

BACKGROUND: The bulge region of the hair follicle contains resident epithelial stem cells (SCs) that are activated and mobilized during hair growth and after epidermal wounding. However, little is known about the signals that modulate these processes. Clinical and experimental observations show that a reduced supply of sensory innervation is associated with delayed wound healing. Since axon terminals of sensory neurons are among the components of the bulge SC niche, we investigated whether these neurons are involved in the activation and mobilization of the hair stem cells during wound healing. METHODOLOGY/PRINCIPAL FINDINGS: We used neonatal capsaicin treatment to reduce sensory terminals in the rat skin and performed morphometric analyses using design-based stereological methods. Epithelial proliferation was analyzed by quantifying the number of bromodeoxyuridine-labeled (BrdU(+)) nuclei in the epidermis and hair follicles. After wounding, the epidermis of capsaicin-treated rats presented fewer BrdU(+) nuclei than in control rats. To assess SC progeny migration, we employed a double labeling protocol with iododeoxyuridine and chlorodeoxyuridine (IdU(+)/CldU(+)). The proportion of double-labeled cells was similar in the hair follicles of both groups at 32 h postwounding. IdU(+)/CldU(+) cell proportion increased in the epidermis of control rats and decreased in treated rats at 61 h postwounding. The epidermal volume immunostained for keratin 6 was greater in treated rats at 61 h. Confocal microscopy analysis revealed that substance P (SP) and calcitonin gene-related peptide (CGRP) receptor immunoreactivity were both present in CD34(+) and BrdU-retaining cells of the hair follicles. CONCLUSIONS/SIGNIFICANCE: Our results suggest that capsaicin denervation impairs SC progeny egress from the hair follicles, a circumstance associated with a greater epidermal activation. Altogether, these phenomena would explain the longer times for healing in denervated skin. Thus, sensory innervation may play a functional role in the modulation of hair SC physiology during wound healing.

[Practice recommendation for administering mechanical restraint during acute psychiatric hospitalization]. / Eine Empfehlung zur Durchführungspraxis von Fixierungen im Rahmen der stationären psychiatrischen Akutbehandlung.

OBJECTIVE: One aim of the multi-site EUNOMIA-project was to establish a European recommendation for the best clinical practice of administering coercive measures. This article reports the results on mechanical restraint. METHODS: Local expert groups in 11 countries worked out their recommendations mostly in semi-structured group discussions. By use of a system of categories developed with a content-analytical method, these national documents were comparatively assessed, and integrated into a common clinical recommendation. RESULTS: Legal and clinical pre-conditions for the use of mechanical restraint, specific instructions for the clinical behaviour of different professional groups, ethical issues, and procedural aspects of quality assurance are reported in detail. CONCLUSIONS: Compared with established clinical guidelines, similarities concerning basic principles of clinical use appear to be higher than similarities concerning practical details. Future development of guidelines for the best practice of coercive measures urgently needs the use of advanced methodology.

Tratamiento quirurgico de la hernia hiatal: analisis de tres anos. / Surgical treatment of hiatal hernia: analysis of 3 years

La hernia hiatal es un padecimiento frecuente, con manifestaciones clinicas variables; generalmente su tratamiento es medico-dietetico, pero cuando este fracasa o aparecen complicaciones el tratamiento debe ser quirurgico. En un lapso de tres anos se atendieron 92 enfermos con hernia hiatal, a quienes se les efectuaron 97 intervenciones quirurgicas. En 74 pacientes la hernia fue por deslizamiento, en seis paraesofagico, en tres mixta y en nueve enfermos se establecio el diagnostico de esofago de Barret. La via de abordaje fue abdominal en 80, toracica en 14 y toraco-abdominal en tres, los procedimientos quirurgicos realizados fueron: cierre de pilares 84, funduplastia posterior 62, funduplastia completa 29, dilataciones transoperatorias 19, gastrostomia seis, plastia tipo Belsey tres, anastomosis esofago gastrica dos y parche de Thal uno.Los resultados fueron buenos en 80 enfermos, regulares en ocho y malos en cuatro que fallecieron, dos por complicaciones quirurgicas inmediatas y dos por complicaciones cardiovasculares. Concluimos que el tratamiento quirurgico oportuno, antes de que aparezcan complicaciones, eligiendo la tecnica mas adecuada de acuerdo con las condiciones particulares de cada enfermo, mejora el pronostico, en cambio la mayor edad, obesidad, recidiva y estenosis, favorecen la aparicion de complicaciones

Resultados con el tratamiento quirúrgico en 51 pacientes con cáncer de esófago / Surgical results in 51 patients coursing with cancer of the esophagus

Antecedentes: Frecuentemente el diagnóstico del cáncer de esófago se hace cuando ya no se puede ofrecer posibilidades de curación a los pacientes. Objetivo: analizar la experiencia con el tratamiento quirúrgico del cáncer de esófago en el Hospital de Especialidades del Centro Médico "La Raza". Metodología: Análisis retrospectivo, transversal y abierto de la información contenida en 51 expedientes de pacientes con cáncer de esófago, dividos en tres grupos de acuerdo a la estirpe histológica (carcinoma epidermoide, adenocarcinoma y esófago de Barrett con adenocarcinoma). Análisis estadístico: Se utilizó la prueba de chi cuadrada y la probabilidad exacta de Fisher para las variables no paramétricas, mientras que para las variables numéricas se utilizó la prueba t de Student y el análisis de varianza. Se hicieron curvas de sobrevida actuarial de Kaplan-Meier. Resultados: Se corroboraron algunos factores de riesgo para el desarrollo del cáncer de esófago. De los pacientes estudiados ninguno pudo clasificarse dentro de la etapa I. No se encontró diferencia en la sobrevida, morbilidad o mortalidad operatoria en función del tipo de operación realizada (p<0.05), sin embargo, si hubo diferencia significativa en la sobrevida de los pacientes en etapa II respecto a los de la III (p=0.003). Conclusiones: La mayoría de los pacientes se diagnosticaron en etapas avanzadas de la enfermedad. No existió diferencia en la sobrevida de los pacientes en función del tipo histológico del tumor o la operación efectuda, sin embargo sí se demostró que los pacientes diagnosticados en etapa II vivieron algunos meses más que los de la etapa III. Estos resultados sugieren que en la mayor parte de los enfermos analizados el tratamiento quirúrgico estuvo limitado a un papel paliativo

Enfermedad de Hirschprung en el adulto joven / Hirscgprung's disease in the young adult

Objetivo: Describir los resultados obtenidos en 5 pacientes con enfermedad de Hirschprung, diagnosticados y operados en la edad adulta. Sede: Servicios de Cirugía General y Proctología del Hospital de Especialidades del Centro Médico Nacional La Raza del IMSS en México, D.F. Diseño: Estudio retrospectivo, longitudinal, con descripción de casos. Resultados: Cinco pacientes jóvenes, 3 hombres y 2 mujeres, con edades de 18 a 33 años, media de 23, fueron diagnosticados, mediante estudio clínico, radiológico, manométrico e histopatológico, de ser portadores de la enfermedad de hirschprung. Los principales datos clínicos fueron: constipación crónica, desnutrición y empleo frecuente de laxantes. En todos se corroboró radiológicamente megacolon; manométricamente, en 3 de ellos no se obtuvo el reflejo de la defecación al insuflar el balón rectal con 200 ml de aire (respuesta normal a los 90 ml), y en todos se demostró, mediante biopsia rectal, ausencia total de plexos sub-mucosos (Meissner y Henle) y mientéricos (Auerbach). Todos fueron operados, en 3 se realizó la operación se Soave, en 1 esfinterectomía rectal y en el otro, resección del sigmoides y de la unión recto-sigmoidea, no hubo mortalidad. Conclusión: A un cuando la enfermedad de Hischprug es rara en el adulto, debe pensarse en ella cuando se trate de adultos jóvenes, con constipación crónica y dilatación del colon.

Tratamiento quirúrgico de la estenosis esofágica por reflujo / Surgical treatment of the reflux esophageal stenosis

Se presentan los resultados de las operaciones de 70 pacientes con estenosis esofágica benigna por reflujo gastroesofágico. El tratamiento quirúrgico se dividió en cuatro categorías: a) Procedimientos reconstructivos (64.2 por ciento) b) procedimientos resectivos (17.2 por cinto) c) Procedimientos derivativos (14.2 por ciento) d) Procedimientos alternos (4.2 por ciento). La morbilidad perioperatoria fue de 4.2 por ciento y la mortalidad de 1.4 por ciento. La evaluación postoperatoria se hizo a 12.6 meses en promedio y 7/70 pacientes tuvieron que reintervenirse por persistencia del reflujo y la estenosis. Consideramos que el paciente con estenosis esofágica por reflujo debe estudiarse cuidadosamente. Es deseable rehabilitar el esófago hasta donde sea posible y dejar los procedimientos resectivos como último recursos. El seguimiento postoperatorio necesariamente debe hacerse a largo plazo.