Massive enlargement of gastric pouch as a complication of gastrojejunal anastomotic stenosis following one anastomosis laparoscopic gastric bypass: A case report.

INTRODUCTION AND IMPORTANCE: By 2030 it is predicted that 1 in 5 women and 1 in 7 men will be living with obesity. The only long-term effective strategy for achieving significant weight loss over time is surgical treatment. One Anastomosis Gastric Bypass (OAGB) has been proposed as an effective therapeutic option. Stenosis of Gastro-Jejunal Anastomosis (GJA) is one of the most common long-term complications and its cause recognized as multifactorial. CASE PRESENTATION: We present the case of a patient with a history of progressive postoperative oral intolerance after OAGB with 60 kg weight loss (BMI 20.7 kg/m2). Severe stenosis of the GJA and massive dilation of the gastric remnant was documented, treated multiple times with endoscopic balloon dilation. He was referred to our unit due to persistent symptoms. Revision surgery to a Gastric Bypass was programmed, ultimately performed via an open approach with resection of 80 % of the gastric remnant. CLINICAL DISCUSSION: Endoscopic dilatation and surgical revision are the two primary treatment options for GJA stricture. In refractory cases to pneumatic dilation, laparoscopic revision surgery is indicated, however an open approach is frequently required, as surgeries are technically demanding due to distorted anatomy in this population. CONCLUSION: Operations to correct chronic complications are tailored to the patient's anatomy as well as the symptoms or pathologies they are intended to correct. Whilst revision surgeries are associated with an increased risk of conversion, complications and longer hospital stay, they can be performed safely in experienced centers.

Prolactin reduces the kainic acid-induced increase in intracellular Ca2+ concentration, leading to neuroprotection of hippocampal neurons.

The aim of this study was to determine the effect of prolactin (PRL) on intracellular calcium (Ca2+) concentration and its neuroprotective role in a model of kainic acid (KA) excitotoxicity in primary cultures of hippocampal neurons. Cell viability and intracellular Ca2+ concentrations were determined by MTT and Fura-2 assays, respectively, either after induction by KA as an agonist or after treatment with NBQX antagonist alone or in combination with PRL administration. Expression of ionotropic glutamatergic receptors (iGluRs) subunits in neuronal cells was determined by RT-qPCR. Dose-response treatments with KA or glutamate (Glu), the latter used as endogenous agonist control, induced a significant increase in neuronal intracellular Ca2+ concentration followed by a significant decrease in hippocampal neuronal viability. Administration of PRL induced a significant increase in neuronal viability after treatment with KA. Furthermore, administration of PRL decreased intracellular Ca2+ concentrations induced by KA treatment. Independent administration of the AMPAR-KAR antagonist reversed cell death and reduced intracellular Ca2+ concentration in a similar manner as PRL. Additionally, mRNA expression of AMPAR, KAR and NMDAR subtypes were detected in hippocampal neurons; however, no significant changes in iGluRs subunit expression were observed due to excitotoxicity or PRL treatment. The results suggest that PRL inhibits the increase in intracellular Ca2+ concentration induced by KA, leading to neuroprotection.

Prolactin-induced neuroprotection against excitotoxicity is mediated via PI3K/AKT and GSK3ß/NF-κB in primary cultures of hippocampal neurons.

Prolactin (PRL) is a polypeptide hormone that has been reported to play a significant role in neuroprotection against neuronal excitotoxicity produced by glutamate (Glu) or kainic acid (KA) in both, in vitro and in vivo models. However, the molecular mechanisms involved in PRL's neuroprotective effects in the hippocampus have not been completely elucidated. The aim of the present study was to assess the signaling pathways involved in PRL neuroprotection against excitotoxicity. Primary rat hippocampal neuronal cell cultures were used to assess PRL-induced signaling pathway activation. The effects of PRL on neuronal viability, as well as its effects on activation of key regulatory pathways, phosphoinositide 3-kinases/Protein Kinase B (PI3K/AKT) and glycogen synthase kinase 3ß / nuclear factor kappa B (GSK3ß/NF-κB), were evaluated under conditions of Glutamate-induced excitotoxicity. Additionally, the effect on downstream regulated genes such as Bcl-2 and Nrf2, was assessed. Here, we show that the PI3K/AKT signaling pathway is activated by PRL treatment during excitotoxicity, promoting neuronal survival through upregulation of active AKT and GSK3ß/NF-κB, resulting in induction of Bcl-2 and Nrf2 gene expression. Inhibition of the PI3K/AKT signaling pathway abrogated the protective effect of PRL against Glu-induced neuronal death. Overall, results indicate that the neuroprotective actions of PRL are mediated in part, by the activation of the AKT pathway and survival genes. Our data support the idea that PRL could be useful as a potential neuroprotective agent in different neurological and neurodegenerative diseases.

College student athlete versus nonathlete mental and social health factors during the COVID-19 pandemic.

Objective: This study investigated differences in stress, anxiety, and social support between collegiate student-athletes and nonathletes during the COVID-19 pandemic. Participants: College students enrolled at a NCAA Division III private liberal arts college in the Midwest. Methods: Participants (n = 58) completed a series of surveys each month for 4 months that included the Generalized Anxiety Disorder Questionnaire, Perceived Stress Scale Questionnaire, and Multidimensional Scale of Perceived Social Support Questionnaire. Results: There were significant main effects of time for stress and social support across the 4 months (p < 0.05), but not for anxiety. There was a significant difference in anxiety levels between athletes and nonathletes (p < 0.01), but not for social support or stress (p > 0.05). Conclusions: Nonathletes maintained support networks, or found alternate outlets of support, in addition to coping with anxiety and stress levels when compared to athletes.

Low-cost fabrication of microlasers based on polymeric micropedestals.

Our current work exploits direct laser writing (DLW) and low one-photon absorption (LOPA) in a low-cost three-dimensional optical fabrication system designed to print micrometric polymeric structures. Micropedestals were obtained by focusing a laser beam on a photoresist layer deposited on a silica glass substrate. Subsequent coating with rhodamine 6G dye allows these pedestals to function as microlasers upon optical excitation at 532 nm. Our microlasers, with a diameter of ∼53µm and a height of ∼40µm, exhibit a broad fluorescence peak in the spectral range 540-600 nm, in addition to narrow lasing peaks, exhibiting quality factors Q exceeding 2000 and a lasing threshold of ∼5µJcm-2. The observed free spectral range associated with the lasing peaks of ∼1.3nm is consistent with simulations, which we include in this paper. In addition, we present simulations for the longitudinal shift of the patterning laser spot, which occurs particularly for relatively thick photoresist layers, coupled with a large index contrast at the photoresist top surface. Such a shift could introduce errors in the resulting microfabricated structures if left unaccounted for. We hope that our work will contribute to the development of microlasers for various photonic applications, particularly if dimensions can be reduced, for on-chip optical communications and data processing.

Decoding signaling pathways involved in prolactin-induced neuroprotection: A review.

It has been well recognized that prolactin (PRL), a pleiotropic hormone, has many functions in the brain, such as maternal behavior, neurogenesis, and neuronal plasticity, among others. Recently, it has been reported to have a significant role in neuroprotection against excitotoxicity. Glutamate excitotoxicity is a common alteration in many neurological and neurodegenerative diseases, leading to neuronal death. In this sense, several efforts have been made to decrease the progression of these pathologies. Despite various reports of PRL's neuroprotective effect against excitotoxicity, the signaling pathways that underlie this mechanism remain unclear. This review aims to describe the most recent and relevant studies on the molecular signaling pathways, particularly, PI3K/AKT, NF-κB, and JAK2/STAT5, which are currently under investigation and might be implicated in the molecular mechanisms that explain the PRL effects against excitotoxicity and neuroprotection. Remarkable neuroprotective effects of PRL might be useful in the treatment of some neurological diseases.

Participation of Glutamatergic Ionotropic Receptors in Excitotoxicity: The Neuroprotective Role of Prolactin.

Glutamate (Glu) is known as the main excitatory neurotransmitter in the central nervous system. It can trigger a series of processes ranging from synaptic plasticity to neurophysiological regulation. To carry out its functions, Glu acts via interaction with its cognate receptors, which are ligand-dependent. Glutamatergic receptors include ionotropic and metabotropic categories. The first allows the passage of ions through the postsynaptic membrane, while the metabotropic subtype activates signaling cascades through second messengers. It is well known that an excess of extracellular Glu concentration induces overstimulation of ionotropic glutamatergic receptors (iGluRs), causing the excitotoxicity phenomenon that leads to neuronal damage and cell death. Excitotoxicity plays a crucial role in different brain pathologies such as brain strokes, epilepsy and neurodegenerative disorders. However, until now, there are no effective neuroprotective compounds to prevent or rescue neurons from excitotoxicity. Thus, the continuous elucidation of the molecular mechanisms underlying excitotoxicity in order to prevent damage or neuronal death is necessary. Therefore, the aim of this review was to summarize the current knowledge regarding iGluRs, while describing their structures and molecular mechanisms of action, including their role in excitotoxicity, as well as the current strategies to reduce excitotoxic damage. Particularly, strategies mediated by prolactin, a somatotropin family-related hormone that displays a significant neuroprotective effect against both Glu and kainic acid-induced excitotoxicity in the hippocampus, are described. Finally, the role of prolactin as a possible molecule in the treatment of excitotoxicity in neurological diseases is discussed.

Altered epigenetic features in circulating nucleosomes in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disorder of unknown origin with a highly variable and unpredictable clinical course. Polymorphisms and environmentally induced epigenetic variations seem to determine individual susceptibility to the development of lung fibrosis. METHODS: We have studied circulating epitopes on cell-free nucleosomes (cfnucleosomes) in 50 IPF patients. We have compared untreated IPF (n = 23) with IPF receiving antifibrotic therapy (n = 27) and healthy subjects (HS) (n = 27). We analyzed serum levels of five cfnucleosomes including bound HMGB1 (nucleosomes adducted to high-mobility growth protein B1), mH2A1.1 (nucleosomes containing the histone variant mH2A1.1), 5mC (nucleosomes associated with methylated DNA), and H3K9Ac and H3K27Ac (nucleosomes associated with histone H3 acetylated at lysine 9 or 27 residue). RESULTS: Our findings showed that serum levels of bound HMGB1, mH2A1.1, 5mC, H3K9Ac, and H3K27Ac were significantly lower in IPF patients than in HS (p < 0.001, p < 0.001, p < 0.01, p < 0.001, and p < 0.0001, respectively). Moreover, we found differences in epigenetic profiles between untreated IPF patients and those receiving anti-fibrotic therapy with mH2A1.1 and 5mC being significantly lower in untreated than in treated patients (p < 0.01 and p < 0.05, respectively). Combination of four cfnucleosomes (HMGB1, 5mC, H3K9Ac, and H3K27Ac) allow to discriminate IPF vs HS with a good coefficient of determination (R2 = 0.681). The AUC for the ROC curve computed by this logistic regression was 0.93 (p < 0.001) with 91% sensitivity at 80% specificity. CONCLUSION: Our observations showed that cfnucleosomes (bound HMGB1, mH2A1.1, 5mC, H3K9Ac, and H3K27Ac) might have potential as biomarkers for diagnosis and treatment response. These results deserve further validation in longitudinal cohorts.

Cirugía antiincontinencia en mujeres posmenopáusicas / Anti-incontinence surgery in postmenopausal women

RESUMEN OBJETIVO: comparar la tasa de curación subjetiva y objetiva en mujeres posmenopáusicas después de habérseles realizado cirugía antiincontinencia. MATERIALES Y MÉTODOS: estudio de cohorte, retrospectivo, comparativo, efectuado en pacientes del Instituto Nacional de Perinatología Isidro Espinosa de los Reyes atendidas entre enero de 2009 y diciembre de 2011. Criterios de inclusión: haber sido intervenidas quirúrgicamente para antiincontinencia. Grupo I: menores de 45 años (n=50); grupo II: 45-65 años (n=109); grupo III: mayores de 65 años (n=8). Variables de estudio: curación subjetiva (síntoma) y objetiva (prueba de la tos y estudio de urodinamia). Se analizaron los resultados quirúrgicos, postquirúrgicos y estudio de urodinamia, con estadística descriptiva y análisis bivariado con χ2 y t-Student. RESULTADOS: se estudiaron 167 pacientes con los siguientes resultados: curación subjetiva: 82% en el grupo I y 80.7% en el grupo II, y 100% en el grupo III, con p= no significativa. La curación objetiva se consiguió en: 90% de las pacientes del grupo I, 92.6 del grupo II y 50% en el grupo III, con p no significativa. La cirugía antiincontinencia efectuada fue por vía transobturadora en 52% del grupo I y 48.6% en el grupo II, y vía retropúbica (62.5%) en el grupo III. La estancia hospitalaria fue mayor en el grupo III, de 3 días, con p=0.018. Los cambios en la presión máxima de cierre uretral para el grupo I fueron de 48.8 cmH2O a 43.6 cmH2O, en el grupo II de 46.1 cmH2O a 45.8 cmH2O y en el grupo III de 38.1 cmH2O a 31 cmH2O, valores pre y posquirúrgicos en todos los grupos (p<0.005). CONCLUSIONES: a pesar de la disminución en la curación subjetiva, mayor morbilidad y menor presión máxima de cierre uretral en mujeres mayores de 65 años no existió diferencia clínica en la evolución.

ABSTRACT OBJECTIVE: Compared the rates of objective and subjective cure, in menopause female after incontinence procedures. MATERIALS AND METHODS: Retrospective study, between January 2009 and December 2011, 167 female patients with urinary incontinence who underwent a incontinence procedure, where divided in 3 groups: Group I: under 45 years (n=50), Group II: 45 to 65 years (n=109), Group III: up 65 years (n=8). The sequential outcomes and urodynamic findings were comparing and analyzed. RESULTS: The rates of subjective cure was 82% and 80.7% in Group I and II, 100% in Group 3, p=NS. The rates of objective cure was 90%, 92.6% and 50%, for each group p=NS. The transobturator procedure was the most done in group I and II, 52% and 48.6%, and retropubic procedure in group III 62.5%. The length of hospital stay (3 days) in Group III, p=0.018. The significant lower postoperative maximal urethral closure pressure in all groups, Group I was 48.8 cmH2O to 43.6 cmH2O, Group II was 46.1 cmH2O to 45.8 cmH2O and Group III was 38.1 cmH2O to 31 cmH2O, (p<0.005) CONCLUSION: Despite the decrease in subjective cure, higher morbidity and lower maximum urethral closure pressure in women older than 65 years, there was no clinical difference in the evolution.

Malla para la reparación del prolapso vaginal apical y anterior: resultados subjetivos y complicaciones / Vaginal mesh for repair of apical and anterior vaginal prolapse: subjective outcomes and complications

Resumen Antecedentes: la aplicación de mallas con fijación al ligamento sacroespinoso para corregir el prolapso apical de órganos pélvicos tiene tasas de éxito objetivo de 92%, con 2-12% de eventos adversos. Objetivo: evaluar los resultados clínicos posteriores a la aplicación de la malla UpholdTM en pacientes con prolapso apical, con o sin útero. Materiales y métodos: estudio retrospectivo y descriptivo efectuado en pacientes atendidas en la Clínica de Urología Ginecológica del Instituto Nacionalo de Perinatología Isidro Espinosa de los Reyes entre los meses de noviembre de 2013 a marzo de 2017 con prolapso de órganos pélvicos de la cúpula a quienes se aplicaron mallas que se fijaron al ligamento sacroespinoso. A las pacientes con incontinencia urinaria de esfuerzo se les colocó una cinta mediouretral. Resultados: se estudiaron 22 pacientes de las que 72% (n = 16) tenían histerectomía previa. El estadio del prolapso de órganos pélvicos fue II en 18% (n = 4), III en 41% (n = 9) y IV en 41% (n = 9). El compartimento anterior se encontró afectado en 41% (n = 9) y en 59% (n = 13) el apical. El 54% (n = 12) de las pacientes tenía incontinencia urinaria de esfuerzo. A 9% (n = 2) de las pacientes solo se les colocó la malla UpholdTM, a 45% (n = 10) se les practicó una cirugía concomitante para corrección del prolapso de órganos pélvicos (colpoplastia posterior [n = 5], colpoperineoplastia [ n = 4] y 1 culdoplastia) y para incontinencia urinaria de esfuerzo a 68% (n = 15) se les colocó una cinta mediouretral. El 9% (n = 2) tuvieron lesión vesical, 40% (n = 9) retención urinaria, 4.5% (n = 1) exposición y 4.5% (n = 1) extrusión. El éxito subjetivo y objetivo fue de 100%. Conclusiones: la colocación de la malla Uphold con fines de corrección del prolapso apical tiene buenos resultados, con mínimos efectos adversos. El procedimiento antiincontinencia concomitante incrementa la retención urinaria.

Abstract Introduction: The use of mesh with fixation to sacoespinous ligament (SEL) for correction of pelvic organ prolapse has a success rate of 92% and adverse events are reported in 2-12%. The aim of this study was to evaluate the clinical results after the application of Uphold mesh in women with apical prolapse with or without uterus. Methods: A retrospective and descriptive study, 22 patients with E ≥ II voult pelvic organ prolapse who underwent vault fixation or hysteropexy to SEL and mediourethral tape (CMU) in those with stress urinary incontinence (SUI) from November-2013 to March-2017. Results: 72.7% (n = 16) had previous hysterectomy. The pelvic organ prolapse stage was grade II in 18% (n = 4), III in 41% (n = 9) and IV in 41% (n = 9), the anterior compartment was affected in 40.9% and 59% (n = 13) for apical. 54.5% (n = 12) had SUI. In 9% (n = 2) were placed exclusively Uphold, concomitant surgery was performed for correction of posterior compartment pelvic organ prolapse in 45% (n=10) and at 68% (n = 15) CMU was placed. 9% (n = 2) had bladder injury, 40% (n = 9) urinary retention of patients with CMU application, 4.5% (n = 1) exposure and 4.5% (n = 1) extrusion. Subjective and objective success was 100%. Conclusions: The placement of Uphold has successful results in the correction of apical prolapse. The concomitant anti-incontinence procedure increases the presence of urinary retention.

Reparación de fístula urogenital con interposición de injerto biológico de submucosa intestinal / Urogenital fistula repair with intestinal submucosa biological graft interposition

Resumen ANTECEDENTE: el tratamiento de una fístula genitourinaria compleja es un reto por las múltiples dificultades para conseguir un resultado exitoso; el injerto biológico de intestino porcino puede ser una opción en estos casos. OBJETIVO: describir el diagnóstico de las fístulas genito-urinarias y su reparación con una innovadora interposición de injerto biológico de intestino delgado porcino. MATERIALES Y MÉTODOS: estudio prospectivo de serie de casos con diagnóstico de fístula vésico-vaginal y uretro-vaginal de pacientes atendidas en el Instituto Nacional de Perinatología entre los años 2012 a 2014. Descripción de los datos demográficos de cada paciente, proceso diagnóstico-clínico y estudios de gabinete y laboratorio; características de la fístula, técnica quirúrgica y seguimiento. RESULTADOS: se estudiaron 5 pacientes con fístulas tipo III o vésico-vaginales localizadas en el trígono, 3 de ellas relacionadas con cirugía ginecológica y 2 con un evento obstétrico, y una tipo I o uretrovaginal en la uretra proximal, relacionada con parto instrumentado. En el cierre del segundo plano, para la colocación del injerto biológico, se aplicó la técnica de reparación de Latzko modificada. Una paciente tuvo 4 reparaciones previas, otra una reparación previa y el resto ninguna. El tamaño varió de 0.5 cm a 3 cm. El seguimiento posoperatorio no evidenció recurrencia; una paciente tuvo incontinencia urinaria de esfuerzo un año después. El seguimiento mínimo fue de 1 y el máximo de 2 años. No se registraron complicaciones posoperatorias. CONCLUSIÓN: el injerto de mucosa de intestino delgado porcino para la reparación de fístulas urogenitales complejas y recurrentes fue efectivo en todas las pacientes.

Abstract BACKGROUND: treatment of a complex genitourinary fistula is a challenge given the multiple difficulties to achieve a successful result, the biological grafting of porcine intestine can be an option in these cases. OBJECTIVE: to describe the diagnosis of genitourinary fistulas and their repair with an innovative interposition of small intestine porcine biological graft. MATERIALS AND METHODS: a prospective trial of a series of cases with a diagnosis of vesicovaginal and urethrovaginal fistula in patients of the Instituto Nacional de Perinatología between 2012 to 2014. Description of patient demographics, diagnostic and clinical process, imaging and lab tests; characteristics of the fistula, surgical technique and follow up. RESULTS: 5 patients with type III or vesicovaginal fistulas located in the trigone were studied, 3 of the fistulas are related to gynecological surgery and 2 with an obstetric event and one type 1 or urethrovaginal in the proximal urethra caused by an instrumented delivery. In the closure of the second layer for placement of the biological graft, we applied the modified Latzko repair technique. One patient had 4 previous repairs, another one had one previous repair and the rest had none. The size varied from 0.5 cm to 3 cm. The postoperative follow-up period did not show recurrence; one patient had stress urinary incontinence one year later. The minimum follow-up was 1 year and the maximum 2 years. No postoperative complications were reported. CONCLUSION: the porcine small intestinal submucosa graft for the repair of complex and recurrent urogenital fistulas was effective in all patients.

Seroprevalencia de Sífilis en donantes del banco de sangre del Hospital Universitario de Maracaibo: Periodo 2012- 2014 / Seroprevalence associated with Syphilis in donor blood bank of University Hospital of Maracaibo: Period 2012-2014

La sífilis es una enfermedad infectocontagiosa con afectación sistémica, de evolución aguda o crónica, cuyo agente causal es el Treponema pallidum. Su principal mecanismo de transmisión es el contacto sexual sin protección, seguida de riesgo de contagio por transfusión sanguínea. Objetivo: Determinar la seroprevalencia de sífilis en donantes del banco de sangre del Hospital Universitario de Maracaibo, periodo 2012-2014. Metodología: Se realizó un estudio descriptivo, de corte transversal, no experimental que incluyó encuestas con pruebas serológicas confidenciales basada en el principio de ELISA. Se procesaron un total de 45.356 unidades de sangre. El 84,7% (38.414) de los donantes eran hombres y el 15,3% (6.942) mujeres con una edad promedio de 31,1 años. Durante este periodo se observó que la seroprevalencia general de anticuerpos específicos anti- T. pallidum en estos donantes fue de 2,95% lo que equivale a 1.336 casos de serología positiva, representada por individuos en edades comprendidas entre 29-39 años con un 35,1 % (470). El sexo masculino muestra la mayor frecuencia de donantes positivos con un 87,7% (1.172). Todo esto indica la necesidad de hacer un seguimiento longitudinal a largo plazo y de implementar programas de vigilancia epidemiológica.

Syphilis is an infectious disease with systemic involvement, chronic or acute evolution, whose causal agent is Treponema pallidum. Its main mechanism of transmission is unprotected sexual contact, followed by risk of transmission by blood transfusion. Objective: To determine the seroprevalence associated with syphilis in blood bank donors at the Universitario Hospital of Maracaibo during the period 2012-12014. Methodology: A non-experimental descriptive study, cross-sectional surveys that included confidential serological tests based on the principle of ELISA to detect anti-T. pallidum antibodies was performed. A total of 45,356 units of blood were processed. 84.7% (38,414) of donors were men and 15.3% (6,942) women with an average age of 31.1 years. During this period it was observed that the specific overall seroprevalence of anti- T. pallidum in these donors was 2.95% which is equivalent to 1,336 cases of positive serology, represented by individuals 29-39 aged 35,1% (470). The male shows increased frequency of positive donors with 87.7% (1,172). All this indicates the need for a long-term longitudinal follow and implement epidemiological surveillance programs.

Avaliação da interação biológica entre compósito de quitosana, colágeno e hidroxiapatita e tecido ósseo ovino / Investigation of biological interactions of chitosan-collagen-hydroxyapatite composite with bone tissue in sheep

As lesões em membros de grandes animais são um desafio para médicos veterinários, uma vez que somente a osteossíntese não garante resultados satisfatórios. Muitos pesquisadores vêm se dedicando ao desenvolvimento e estudo de substitutos ósseos produzidos de materiais naturais, como quitosana, colágeno e hidroxiapatita, que auxiliam na regeneração óssea. Seis ovinos fêmeas da raça Santa Inês foram submetidos a ostectomias unicorticais de sete milímetros de diâmetro na região proximal da superfície dorsomedial dos III/IV metacarpianos. Foi implantado compósito de quitosana, colágeno e hidroxiapatita em um membro torácico para avaliação da biocompatibilidade do material ao tecido ósseo ovino, e no membro contralateral foi reproduzida a mesma técnica, porém foi mantido sem preenchimento, como controle. Após 60 dias do procedimento cirúrgico, realizou-se biópsia óssea na área de interface entre biomaterial/osso (membro com compósito) e tecido neoformado/osso (membro controle), para realização de avaliação histológica do material não descalcificado, por meio de microscopia de luz e microscopia eletrônica de varredura. Na análise histomorfométrica, mediante microscopia de luz, foi possível identificar maior porcentagem de tecido neoformado em membro controle, quando comparado ao membro com compósito (80% e 63,5%, respectivamente; P<0,05). Por meio da microscopia eletrônica de varredura, observou-se invasão da estrutura interna do compósito por tecido ósseo neoformado. Não houve formação de tecido cicatricial, reação de corpo estranho ou resposta inflamatória crônica nas amostras analisadas. Conclui-se que o compósito de quitosana, colágeno e hidroxiapatita, quando implantado em tecido ósseo ovino, apresenta biocompatibilidade e perfil osteocondutor.(AU)

Fracture management poses a great challenge to large animal practitioners. Osteosynthesis alone is often insufficient to provide satisfactory outcomes in large animals; therefore, several research efforts have been made to investigate and develop bone substitutes capable of promoting bone regeneration. Chitosan-collagen-hydroxyapatite composites constitute a promising alternative given their similar composition to bone. Six Santa Inês ewes were submitted to the creation of experimental 7mm wide unicortical defects on the dorsomedial aspect of the proximal III/IV metacarpal bone diaphysis. Limbs were randomly selected for treatment with chitosan-collagen-hydroxyapatite composite or to serve as untreated controls. Biopsy fragments were collected from the bone/new bone or the bone/biomaterial interface (control and treated defects respectively) within 60 days of surgery; composite biocompatibility was assessed using light and scanning electron microscopy. Histomorphometric analysis under light microscopy revealed greater percentage of new bone tissue in control compared to treated defects (80% and 63.5% respectively; P<0.05). No scar tissue formation, foreign body or chronic inflammatory reactions were observed. Scanning electron microscopy revealed invasion of the composite by new bone tissue. The chitosan-collagen-hydroxyapatite composite studied is biocompatible with bone and shows osteoconductive properties in sheep.

A pseudo-outbreak of disseminated cryptococcal disease after orthotopic heart transplantation.

Cryptococcal infection is the third most common invasive fungal infection (IFI) among solid-organ transplant (SOT) recipients and is considered an important opportunistic infection due to its significant morbidity and mortality. To determine whether a cluster of cryptococcosis in heart transplant patients was of nosocomial nature, three cases of orthotopic heart transplant recipients with postoperative disseminated cryptococcal infection were investigated and paired with an environmental survey in a tertiary care hospital. The infection prevention department conducted a multidisciplinary investigation, which did not demonstrate any evidence of health care-associated environmental exposure. Moreover, multilocus sequence typing showed that one isolate was unique and the two others, although identical, were not temporally related and belong to the most common type seen in the Southern US. Additionally, all three patients had preexisting abnormalities of the CT chest scan and various degrees of acute and chronic rejection. Reactivation was suggested in all three patients. Screening methods may be useful to identify at risk patients and trigger a prophylactic or preemptive approach. However, more data is needed.

Early detection surveillance for an emerging plant pathogen: a rule of thumb to predict prevalence at first discovery.

Emerging plant pathogens are a significant problem for conservation and food security. Surveillance is often instigated in an attempt to detect an invading epidemic before it gets out of control. Yet in practice many epidemics are not discovered until already at a high prevalence, partly due to a lack of quantitative understanding of how surveillance effort and the dynamics of an invading epidemic relate. We test a simple rule of thumb to determine, for a surveillance programme taking a fixed number of samples at regular intervals, the distribution of the prevalence an epidemic will have reached on first discovery (discovery-prevalence) and its expectation E(q*). We show that E(q*) = r/(N/Δ), i.e. simply the rate of epidemic growth divided by the rate of sampling; where r is the epidemic growth rate, N is the sample size and Δ is the time between sampling rounds. We demonstrate the robustness of this rule of thumb using spatio-temporal epidemic models as well as data from real epidemics. Our work supports the view that, for the purposes of early detection surveillance, simple models can provide useful insights in apparently complex systems. The insight can inform decisions on surveillance resource allocation in plant health and has potential applicability to invasive species generally.

Biosynthesis of silver fine particles and particles decorated with nanoparticles using the extract of Illicium verum (star anise) seeds.

Given the upsurge of new technologies based on nanomaterials, the development of sustainable methods to obtain functional nanostructures has become an imperative task. In this matter, several recent researches have shown that the biodegradable natural antioxidants of several plant extracts can be used simultaneously as reducing and stabilizing agents in the wet chemical synthesis of metallic nanoparticles, opening new opportunities to design greener synthesis. However, the challenge of these new techniques is to produce stable colloidal nanoparticles with controlled particle uniformity, size, shape and aggregation state, in similar manner than the well-established synthetic methods. In the present work, colloidal metallic silver nanoparticles have been synthesized using silver nitrate and extracts of Illicium verum (star anise) seeds at room temperature in a facile one-step procedure. The resulting products were colloidal suspensions of two populations of silver nanoparticles, one of them with particle sizes of few nanometers and the other with particles of tens of nm. Strikingly, the variation of the AgNO3/extract weight ratio in the reaction medium yielded to the variation of the spatial distribution of the nanoparticles: high AgNO3/extract concentration ratios yielded to randomly dispersed particles, whereas for lower AgNO3/extract ratios, the biggest particles appeared coated with the finest nanoparticles. This biosynthesized colloidal system, with controlled particle aggregation states, presents plasmonic and SERS properties with potential applications in molecular sensors and nanophotonic devices.

The effect of the solute on the structure, selected mechanical properties, and biocompatibility of Ti-Zr system alloys for dental applications.

New titanium alloys have been developed with the aim of utilizing materials with better properties for application as biomaterials, and Ti-Zr system alloys are among the more promising of these. In this paper, the influence of zirconium concentrations on the structure, microstructure, and selected mechanical properties of Ti-Zr alloys is analyzed. After melting and swaging, the samples were characterized through chemical analysis, density measurements, X-ray diffraction, optical microscopy, Vickers microhardness, and elasticity modulus. In-vitro cytotoxicity tests were performed on cultured osteogenic cells. The results showed the formation essentially of the α' phase (with hcp structure) and microhardness values greater than cp-Ti. The elasticity modulus of the alloys was sensitive to the zirconium concentrations while remaining within the range of values of conventional titanium alloys. The alloys presented no cytotoxic effects on osteoblastic cells in the studied conditions.

Bis-enoxacin inhibits bone resorption and orthodontic tooth movement.

UNLABELLED: Enoxacin inhibits binding between the B-subunit of vacuolar H(+)-ATPase (V-ATPase) and microfilaments, and also between osteoclast formation and bone resorption in vitro. We hypothesized that a bisphosphonate derivative of enoxacin, bis-enoxacin (BE), which was previously studied as a bone-directed antibiotic, might have similar activities. BE shared a number of characteristics with enoxacin: It blocked binding between the recombinant B-subunit and microfilaments and inhibited osteoclastogenesis in cell culture with IC50s of about 10 µM in each case. BE did not alter the relative expression levels of various osteoclast-specific proteins. Even though tartrate-resistant acid phosphatase 5b was expressed, proteolytic activation of the latent pro-enzyme was inhibited. However, unlike enoxacin, BE stimulated caspase-3 activity. BE bound to bone slices and inhibited bone resorption by osteoclasts on BE-coated bone slices in cell culture. BE reduced the amount of orthodontic tooth movement achieved in rats after 28 days. Analysis of these data suggests that BE is a novel anti-resorptive molecule that is active both in vitro and in vivo and may have clinical uses. ABBREVIATIONS: BE, bis-enoxacin; V-ATPase, vacuolar H(+)-ATPase; TRAP, tartrate-resistant acid phosphatase; αMEM D10, minimal essential media, alpha modification with 10% fetal bovine serum; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; RANKL, receptor activator of nuclear factor kappa B-ligand; NFATc1, nuclear factor of activated T-cells; ADAM, a disintegrin and metalloprotease domain; OTM, orthodontic tooth movement.

Effect of alendronate on endochondral ossification in mandibular condyles of growing rats.

The replacement of the calcified cartilage by bone tissue during the endochondral ossification of the mandibular condyle is dependent of the resorbing activity of osteoclats. After partial resorption, calcified cartilage septa are covered by a primary bone matrix secreted by osteoblasts. Osteoadherin (OSAD) is a small proteoglycan present in bone matrix but absent in cartilage during the endochondral ossification. The aim of this study was to analyze the effect of alendronate, a drug known to inhibit bone resorption by osteoclasts, on the endochondral ossification of the mandibular condyle of young rats, by evaluating the distribution of osteoclasts and the presence of OSAD in the bone matrix deposited. Wistar newborn rats (n=45) received daily injections of alendronate (n=27) or sterile saline solution as control (n=18) from the day of birth until the ages of 4, 14 and 30 days. At the days mentioned, the mandibular condyles were collected and processed for transmission electron microscopy analysis. Specimens were also submitted to tartrate resistant acid phosphatase (TRAP) histochemistry and ultrastructural immunodetection of OSAD. Alendronate treatment did not impede the recruitment and fusion of osteoclasts at the ossification zone during condyle growth, but they presented inactivated phenotype. The trabeculae at the ossification area consisted of cartilage matrix covered by a layer of primary bone matrix that was immunopositive to OSAD at all time points studied. Apparently, alendronate impeded the removal of calcified cartilage and maturation of bone trabeculae in the mandibular ramus, while in controls they occurred normally. These findings highlight for giving attention to the potential side-effects of bisphosphonates administered to young patients once it may represent a risk of disturbing maxillofacial development.

Micro-shear bond strength of different adhesives to human dental enamel.

UNLABELLED: The aim of this study was to evaluate the micro-shear bond strength of 5 adhesive systems to enamel, one single-bottle acid-etch adhesive (O), two self-etching primers (P) and two all-in-one self-etching adhesives (S). METHOD: Sixty premolar enamel surfaces (buccal or lingual) were ground flat with 400- and 600-grit SiC papers and randomly divided into 5 groups (n = 12), according to the adhesive system: SB2--Single Bond 2 (O); CSE--Clearfil SE Bond (P); ADS--AdheSE (P); PLP--Adper Prompt L-Pop (S); XE3--Xeno III (S). Tygon tubing (inner diameter of 0.8 mm) restricted the bonding area to obtain the resin composite (Z250) cylinders. After storage in distilled water at 37 degrees C for 24h and thermocycling, micro-shear testing was performed (crosshead speed of 0.5 mm/min). Data were submitted to one-way ANOVA and Tukey test (a = 5%). Samples were also subjected to stereomicroscopic and SEM evaluations after micro-shear testing. Mean bond strength values (MPa +/- SD) and the results of Tukey test were: SB2: 36.36 (+/- 3.34)a; ADS: 33.03 (17.83)a; XE3: 32.76 (+/- 5.61)a; CSE: 30.61 (+/- 6.68)a; PLP: 22.17 (+/- 6.05)b. Groups with the same letter were not statistically different. It can be concluded that no significant difference was there between SB2, ADS, XE3 and CSE, in spite of different etching patterns of these adhesives. Only PLP presented statistically lower bond strengths compared with others.