Carotid Artery Resection and Reconstruction due to Benign and Malignant Head and Neck Tumors.

OBJECTIVE: Carotid resection for head and neck cancer is rare, and serious complications may arise since such cancer is frequently detected in advanced stages. The objective is to describe nine cases of carotid artery resection and reconstruction due to tumor invasion. METHODS: The clinical records of nine patients who underwent carotid resection and reconstruction at our hospital were retrospectively reviewed. Carotid body tumors were evaluated with the aid of a vascular team in case carotid resection was necessary at the time of surgery. CT angiography to determine the status of the circle of Willis was performed in all patients who might undergo carotid resection and reconstruction in case of failure to restore cerebral blood flow and thus reduce possible sequelae due to ligation. RESULTS: Of nine patients, 6 had carotid body tumors, 1 had a thyroid tumor of conglomerate lymph nodes, 1 had a larynx tumor of conglomerate lymph nodes, and 1 had a myofibroblastic tumor. There were no intraoperative cerebrovascular accidents. One patient (11.1%) had a cerebrovascular accident secondary to carotid hematoma in the intermediate postoperative period that required vascular graft removal. One patient (11.1%) died seven days after surgery following an ischemic cerebrovascular accident. Eight patients remain asymptomatic, and 1 patient with recurrence and metastasis. CONCLUSIONS: Carotid resection remains a controversial issue in the treatment of advanced head and neck cancer. However, carotid resection and reconstruction are required for disease control, and complications such as thrombosis or vascular accidents may arise. Fortunately, this is a rare condition. We recommend carotid reconstruction for all patients in whom resection is required for tumor control. Ligation should be a last resort, as seen in the management of one of our patients.

Reduced Levels of Selenium and Thioredoxin Reductase in the Thoracic Aorta Could Contribute to Aneurysm Formation in Patients with Marfan Syndrome.

Marfan syndrome (MFS) is an autosomal dominant disorder caused by a heterozygous mutation of the FBN1 gene. MFS patients present oxidative stress that disturbs redox homeostasis. Redox homeostasis depends in part on the enzymatic antioxidant system, which includes thioredoxin reductase (TrxR) and glutathione peroxidases (GPx), both of which require an adequate concentration of selenium (Se). Therefore, the aim of this study was to determine if Se levels are decreased in the TAA of patients with MFS since this could contribute to the formation of an aneurysm in these patients. The results show that interleukins IL-1ß, IL-6 TGF-ß1, and TNF-α (p ≤ 0.03), and carbonylation (p ≤ 0.03) were increased in the TAA of patients with MFS in comparison with control subjects, while Se, thiols (p = 0.02), TrxR, and GPx (p ≤ 0.001) were decreased. TLR4 and NOX1 (p ≤ 0.03), MMP9 and MMP2 (p = 0.04) and NOS2 (p < 0.001) were also increased. Therefore, Se concentrations are decreased in the TAA of MFS, which can contribute to a decrease in the activities of TrxR and GPx, and thiol groups. A decrease in the activities of these enzymes can lead to the loss of redox homeostasis, which can, in turn, lead to an increase in the pro-inflammatory interleukins associated with the overexpression of MMP9 and MMP2.

Seguridad y eficacia de la bioprótesis de válvula cardiaca INC en humanos / Safety and efficacy of the INC bioprosthetic heart valve in humans

Resumen Introducción: Las bioprótesis de válvulas cardiacas son el estándar de oro para el reemplazo quirúrgico de la válvula aórtica en pacientes seleccionados. Objetivo: Evaluar la seguridad y eficacia de la válvula cardiaca bioprotésica del Instituto Nacional de Cardiología (INC) en humanos. Métodos: Estudio unicéntrico que incluyó 341 pacientes que se sometieron a reemplazo valvular quirúrgico único de válvula aórtica con válvula INC. Resultados: Se realizaron 318 implantes de novo (93 %) y 23 como segunda cirugía (7 %); las puntuaciones STS fueron de 1.4 y 1.8 % y el seguimiento de 42 y 46 meses, respectivamente. No existieron diferencias en las complicaciones ni en la tasa de implantación de marcapasos. Ambos grupos mantuvieron una FEVI normal. Se observó mejoría global en la clase funcional con empeoramiento solo en dos pacientes del grupo de novo. La disfunción de la prótesis INC que ameritó reintervención quirúrgica se observó en ocho pacientes (4.65 %) del grupo de novo versus un paciente (7.69 %) con segunda cirugía. Conclusiones: La válvula cardiaca INC es eficaz y segura, se asocia a baja tasa de complicaciones y mejoría de la clase funcional durante el seguimiento a largo plazo. Se necesitan estudios prospectivos comparativos de esta válvula.

Abstract Introduction: Heart valve bioprostheses are the gold standard for aortic valve surgical replacement in selected patients. Objective: To evaluate the safety and efficacy of the of the National Institute of Cardiology (INC) bioprosthetic heart alve of the National Institute of Cardiology (INC) bioprosthetic heart valve in humans. Methods: Single-center study that ncluded 341 patients who underwent single surgical aortic valve replacement with INC heart valve. Results: 318 implants were performed de novo (93%) and 23 as redo surgery (7%); STS scores were 1.4 and 1.8%, and follow-up was for 42 and 46 months, respectively. There were no differences in clinical complications or pacemaker implantation rate. Both groups maintained a normal LVEF. Overall improvement in functional class was observed, with worsening only in two patients of the de novo group. INC prosthesis dysfunction requiring surgical reintervention was observed in eight patients (4.65%) of the de novo group vs. one patient in the redo group. Conclusions: The INC heart valve is efficacious and safe, and is associated with a The INC heart valve is efficacious and safe, and is associated with a low rate of complications and functional class improvement during long-term follow-up. Prospective, comparative studies of this valve are required.

Toll-Like Receptor 4 Signaling in the Trabecular Meshwork.

Primary open-angle glaucoma is one of the leading causes of blindness worldwide. With limited therapeutics targeting the pathogenesis at the trabecular meshwork (TM), there is a great need for identifying potential new targets. Recent evidence has implicated Toll-like receptor 4 (TLR4) and it is signaling pathway in augmenting the effects of transforming growth factor beta-2 (TGFß2) and downstream extracellular matrix production. In this review, we examine the role of TLR4 signaling in the trabecular meshwork and the interplay between endogenous activators of TLR4 (damage-associated molecular patterns (DAMPs)), extracellular matrix (ECM), and the effect on intraocular pressure.

Cardiothoracic surgery and peripheral endovascular intervention in cardiovascular damage from a cohort of orphan rheumatological diseases-epidemiological and survival analysis.

Background: Aortic diseases in some orphan rheumatological diseases require medical, surgical or peripheral endovascular intervention because they can be catastrophic. Objectives: to analyze the main clinical and epidemiological characteristics of patients with Takayasu arteritis (TA), Marfan syndrome (MS) and similar conditions that were treated with cardiothoracic surgery and peripheral endovascular intervention. Methods: Retrospective and descriptive cohort study that included patients of any age and gender with TA (as per the criteria of the American College of Rheumatology and EULAR/PRINTO), MS (according to Ghent criteria), and similar conditions who underwent cardiothoracic surgery or peripheral endovascular intervention. Data were collected from electronic charts. Results: A total of 77 patients with TA and 135 patients with MS and similar conditions were included. The frequency of surgical or interventional requirements in patients with TA and MS/similar conditions was 77/364 (21.2%) and 135/300 (45%), respectively; such patients were followed for a median of 6 [2-12] and 3.29 (0.42-6.62) years, with (maximum follow-up range of 47 and 21.37 years, respectively). Aneurysms were present in 11 (14.3%) and 66 (48.9%) in patients with TA and MS/similar conditions, respectively. Aortic, mitral and tricuspid valve damage occurred in 8 (10.4%) patients, 4 (5.2%) patients and 1 (1.3%) patient with TA, respectively; corresponding frequencies in patients with MS/similar conditions were 98 (72.6%), 50 (37.0%) and 20 (14.8%). We identified that 20% of patients with TA died after 5.08 years (95% CI: 0.23-25.42 years) and 20 % of the patients with MS and other similar conditions died after 7.52 years (95% CI: 1.10-9.02 years). Conclusions: The frequency of surgical intervention was low in this study. Long-term prognosis is good if surgery is performed in a timely manner. Epidemiological studies provide relevant information for public health decisions related to the management of orphan rheumatological diseases.

Gut-derived butyrate suppresses ocular surface inflammation.

Dry eye is a common ocular inflammatory disorder characterized by tear film instability and reduced tear production. There is increasing evidence that homeostasis of the ocular surface is impacted by the intestinal microbiome. We are interested in investigating the potential role of microbially produced small molecules in mediating the interaction between the intestinal microbiota and the ocular surface. One such molecule is butyrate, a short-chain fatty acid (SCFA) produced by certain members of the gut microbiota through fermentation of dietary fiber. Here we show that SCFA transporter SLC5A8 is expressed in vivo in murine conjunctival and corneal epithelium. Pre-treatment of in vitro corneal epithelial cultures or bone marrow-derived dendritic cells (BMDCs) with phenylbutyrate (PBA) reduces lipopolysaccharide-induced pro-inflammatory Tnf expression. Corneal epithelial cultures and BMDCs isolated from Slc5a8 knockout mice are unable to respond to PBA pre-treatment, suggesting that SLC5A8 is required for the protective effect of PBA. The treatment of mice undergoing desiccating stress (DS) with oral tributyrin, a prodrug form of butyrate, reduces inflammation at the ocular surface in vivo, and this effect partially requires SLC5A8. Finally, expression analysis on conjunctival tissue isolated from mice subjected to DS with and without tributyrin treatment revealed that treatment downregulated genes involved in Type I interferon signaling. Together these data support our hypothesis that SCFAs produced in the gut participate in the maintenance of ocular surface homeostasis.

Immune phenotype of the CD4+ T cells in the aged lymphoid organs and lacrimal glands.

Aging is associated with a massive infiltration of T lymphocytes in the lacrimal gland. Here, we aimed to characterize the immune phenotype of aged CD4+ T cells in this tissue as compared with lymphoid organs. To perform this, we sorted regulatory T cells (Tregs, CD4+CD25+GITR+) and non-Tregs (CD4+CD25negGITRneg) in lymphoid organs from female C57BL/6J mice and subjected these cells to an immunology NanoString® panel. These results were confirmed by flow cytometry, live imaging, and tissue immunostaining in the lacrimal gland. Importantly, effector T helper 1 (Th1) genes were highly upregulated on aged Tregs, including the master regulator Tbx21. Among the non-Tregs, we also found a significant increase in the levels of EOMESmed/high, TbetnegIFN-γ+, and CD62L+CD44negCD4+ T cells with aging, which are associated with cell exhaustion, immunopathology, and the generation of tertiary lymphoid tissue. At the functional level, aged Tregs from lymphoid organs are less able to decrease proliferation and IFN-γ production of T responders at any age. More importantly, human lacrimal glands (age range 55-81 years) also showed the presence of CD4+Foxp3+ cells. Further studies are needed to propose potential molecular targets to avoid immune-mediated lacrimal gland dysfunction with aging.

Consensus Recommendation for Mouse Models of Ocular Hypertension to Study Aqueous Humor Outflow and Its Mechanisms.

Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension. We expect that this set of standard practices will increase scientific rigor when using mouse models and will better enable researchers to replicate and build upon previous findings.

Safety and efficacy of the INC bioprosthetic heart valve in humans.

INTRODUCTION: Heart valve bioprostheses are the gold standard for aortic valve surgical replacement in selected patients. OBJECTIVE: To evaluate the safety and efficacy of the National Institute of Cardiology (INC) bioprosthetic heart valve in humans. METHODS: Single-center study that included 341 patients who underwent single surgical aortic valve replacement with INC heart valve. RESULTS: 318 implants were performed de novo (93%) and 23 as redo surgery (7%); STS scores were 1.4 and 1.8%, and follow-up was for 42 and 46 months, respectively. There were no differences in clinical complications or pacemaker implantation rate. Both groups maintained a normal LVEF. Overall improvement in functional class was observed, with worsening only in two patients of the de novo group. INC prosthesis dysfunction requiring surgical reintervention was observed in eight patients (4.65%) of the de novo group vs. one patient in the redo group. CONCLUSIONS: The INC heart valve is efficacious and safe, and is associated with a low rate of complications and functional class improvement during long-term follow-up. Prospective, comparative studies of this valve are required.

INTRODUCCIÓN: Las bioprótesis de válvulas cardiacas son el estándar de oro para el reemplazo quirúrgico de la válvula aórtica en pacientes seleccionados. OBJETIVO: Evaluar la seguridad y eficacia de la válvula cardiaca bioprotésica del Instituto Nacional de Cardiología (INC) en humanos. MÉTODOS: Estudio unicéntrico que incluyó 341 pacientes que se sometieron a reemplazo valvular quirúrgico único de válvula aórtica con válvula INC. RESULTADOS: Se realizaron 318 implantes de novo (93 %) y 23 como segunda cirugía (7 %); las puntuaciones STS fueron de 1.4 y 1.8 % y el seguimiento de 42 y 46 meses, respectivamente. No existieron diferencias en las complicaciones ni en la tasa de implantación de marcapasos. Ambos grupos mantuvieron una FEVI normal. Se observó mejoría global en la clase funcional con empeoramiento solo en dos pacientes del grupo de novo. La disfunción de la prótesis INC que ameritó reintervención quirúrgica se observó en ocho pacientes (4.65 %) del grupo de novo versus un paciente (7.69 %) con segunda cirugía. CONCLUSIONES: La válvula cardiaca INC es eficaz y segura, se asocia a baja tasa de complicaciones y mejoría de la clase funcional durante el seguimiento a largo plazo. Se necesitan estudios prospectivos comparativos de esta válvula.

The key to simplified management of an undescended parathyroid adenoma.

Undescended parathyroid adenoma is a rare cause of primary hyperparathyroidism that happens < 1% of cases. If not suspected, it can lead to a negative bilateral parathyroid exploration and extensive iatrogenic trauma. We propose that with proper imaging the correct diagnosis can be established to simplify surgical management. We describe two cases of patients who underwent a targeted neck exploration due to an undescended parathyroid adenoma diagnosed with an appropriate preoperative imaging protocol. With an appropriate imaging protocol for primary hyperparathyroidism and parathyroid hormone aspirates, an undescended parathyroid adenoma can be primarily diagnosed to guide a focused parathyroidectomy.

El adenoma paratiroideo no descendido ocasiona hiperparatiroidismo primario en <1% de los casos. Si no se sospecha, puede llevar a exploraciones negativas y trauma iatrogénico extenso. Proponemos que, con un protocolo imagenológico adecuado, se puede realizar un diagnóstico correcto, simplificando el abordaje quirúrgico. Describimos dos casos en que se realizó una exploración de cuello dirigida debido a un adenoma paratiroideo no descendido diagnosticado con un protocolo de imagen preoperatorio apropiado. Un protocolo de imagen apropiado para hiperparatiroidismo primario y aspirados de PTH pueden diagnosticar de manera inicial un adenoma paratiroideo no descendido para guiar una paratiroidectomía dirigida.

Modeling spatial pattern of dengue in North Central Mexico using survey data and logistic regression.

Dengue is a major public health concern mainly in tropical and subtropical environments worldwide. Despite several attempts to prevent this disease occurring in tropical regions of Mexico, it has not yet been controlled. This work focused on spatial modeling of confirmed dengue fever cases that occurred during the period 2010-2014 in the Huasteca Potosina region of Mexico. Multivariable Logistic Regression Modeling (MLRM) was used to determine the relationship between explanatory variables and the presence/absence of dengue. Model performance was evaluated using the area under curve (AUC) of the relative operating characteristic (ROC); AUC > 0.95. A high spatial resolution map was created to reveal the most probable patterns of dengue risk. Our results can be used for targeted control and prevention programs at local and regional levels. This methodology can be applied to other major diseases that are spatially distributed in accordance with environmental factors.

Modulation of Oxidative Stress and Inflammation in the Aged Lacrimal Gland.

Inflammation and oxidative stress accompany aging. This study investigated the interplay between oxidative stress and inflammation in the lacrimal gland. C57BL/6 mice were used at 2 to 3, 12, and 24 months of age. Nuclear factor erythroid derived-2-related factor 2 (Nrf2)-/- and corresponding wild-type mice were used at 2 to 3 and 12 to 13 months of age. A separate group of 15.5 to 17 months of age C57BL/6 mice received a diet containing an Nrf2 inducer (Oltipraz) for 8 weeks. Aged C57BL/6 lacrimal glands showed significantly greater lymphocytic infiltration, higher levels of MHC II, IFN-γ, IL-1ß, TNF-α, and cathepsin S (Ctss) mRNA transcripts, and greater nitrotyrosine and 4-hydroxynonenal protein. Young Nrf2-/- mice showed an increase in IL-1ß, IFN-γ, MHC II, and Ctss mRNA transcripts compared with young wild-type mice and greater age-related changes at 12 to 13 months of age. Oltipraz diet significantly decreased nitrotyrosine and 4-hydroxynonenal and decreased the expression of IL-1ß and TNF-α mRNA transcripts, while decreasing the frequency of CD45+CD4+ cells in lacrimal glands and significantly increasing conjunctival goblet cell density compared with a standard diet. The findings provide novel insight into the development of chronic, low-grade inflammation and oxidative stress in age-related dry eye. New therapies targeting oxidative stress pathways will be valuable in treating age-related dry eye.

Efecto de extractos orgánicos naturales sobre la micropropagación in vitro de Vanilla planifolia Jacks. ex Andrews (Orchidaceae) / Effect of natural extracts on the micropropagation of Vanilla planifolia Jacks. ex Andrews (Orchidaceae)

Vanilla planifolia Jacks. ex Andrews es una orquídea de gran importancia económica, que presenta problemas de sobreexplotación y amenaza en su hábitat original. Por lo cual, el objetivo de esta investigación fue establecer un protocolo de micropropagación in vitro evaluando el efecto diferentes extractos orgánicos. El cultivo in vitro se inició a través de la germinación de semillas que dieron lugar a la formación de protocormos. Los protocormos se cultivaron en medios MS suplementados con extractos naturales: MPL (plátano), MPI (piña), MCO (agua de coco) y medio control, para promover la morfogénesis. Posteriormente, para inducir la rizogénesis de los brotes y la aclimatación, se utilizaron tratamientos con auxinas (AIA y AIB). Los resultados mostraron que la germinación inició a los 60 días de cultivo in vitro, y que la adición de los extractos orgánicos promovió la diferenciación de los brotes, resultando más eficiente el tratamiento MPI. Además, la adición de 0.5 mg L-1 de AIA promovió el enraizamiento y la pre aclimatación in vitro. Estos resultados sugieren que los extractos orgánicos promueven la morfogénesis de vainilla, sin necesidad de emplear reguladores de crecimiento sintéticos en las primeras etapas de la micropropagación in vitro.

Rapamycin Eyedrops Increased CD4+Foxp3+ Cells and Prevented Goblet Cell Loss in the Aged Ocular Surface.

Dry eye disease (DED), one of the most prevalent conditions among the elderly, is a chronic inflammatory disorder that disrupts tear film stability and causes ocular surface damage. Aged C57BL/6J mice spontaneously develop DED. Rapamycin is a potent immunosuppressant that prolongs the lifespan of several species. Here, we compared the effects of daily instillation of eyedrops containing rapamycin or empty micelles for three months on the aged mice. Tear cytokine/chemokine profile showed a pronounced increase in vascular endothelial cell growth factor-A (VEGF-A) and a trend towards decreased concentration of Interferon gamma (IFN)-γ in rapamycin-treated groups. A significant decrease in inflammatory markers in the lacrimal gland was also evident (IFN-γ, IL-12, CIITA and Ctss); this was accompanied by slightly diminished Unc-51 Like Autophagy Activating Kinase 1 (ULK1) transcripts. In the lacrimal gland and draining lymph nodes, we also observed a significant increase in the CD45+CD4+Foxp3+ cells in the rapamycin-treated mice. More importantly, rapamycin eyedrops increased conjunctival goblet cell density and area compared to the empty micelles. Taken together, evidence from these studies indicates that topical rapamycin has therapeutic efficacy for age-associated ocular surface inflammation and goblet cell loss and opens the venue for new investigations on its role in the aging process of the eye.

Nuclear factor-kappa beta signaling is required for transforming growth factor Beta-2 induced ocular hypertension.

A major risk for the development of primary open-angle glaucoma (POAG) is elevated intraocular pressure (IOP). Elevated IOP is caused by increased outflow resistance due in part to excessive extracellular matrix (ECM) deposition in the trabecular meshwork (TM). The role of transforming growth factor beta 2 (TGFß2) in inducing ECM production is well understood. Recent studies suggest that toll-like receptor 4 (TLR4) plays an important role in fibrogenesis. We have previously described a crosstalk between TGFß2 and TLR4 in the development of ocular hypertension and glaucomatous TM damage. Nuclear factor-kappa beta (NF-κB) is critical for TLR4 signaling. To determine the transactivation of NF-κB, TM cells were stimulated with cellular fibronectin containing the EDA isoform (cFN-EDA), TGFß2, or lipopolysaccharide (LPS) in combination with a selective TLR4 inhibitor. cFN-EDA, TGFß2, and LPS all induced transactivation of NF-κB and inhibition of TLR4 blocked the effect of each treatment paradigm. To evaluate the role of NF-κB in IOP regulation, we utilized our inducible mouse model of ocular hypertension by injection of Ad5.TGFß2 in mice harboring a mutation in NF-κB and wild-type controls. IOP was measured over time and eyes accessed by immunohistochemistry for the ECM protein FN and the specific FN-EDA isoform. Ad5.TGFß2 induced ocular hypertension and expression of FN and FN-EDA in wild-type mice, but mutation in NF-κB blocked the effect. These data suggest that NF-κB is necessary for TGFß2-induced ECM production and ocular hypertension and the transactivation of NF-κB is dependent on both TGFß2 and TLR4.

Age-associated antigen-presenting cell alterations promote dry-eye inducing Th1 cells.

Aging is a significant risk factor for dry eye. Here we used a murine aging model to investigate the effects of aging on antigen presenting cells (APCs) and generation of pathogenic T helper (Th)-1 cells. Our results showed that APCs from aged mice accumulate at the conjunctiva, have higher levels of co-activation marker CD86 and lower aldehyde dehydrogenase activity. Using topical ovalbumin peptide as a surrogate antigen, we observed an increased number of antigen-loaded APCs in the draining cervical lymph nodes in the aged group and loss of tight junction protein occludin in the conjunctiva. Aged cervical lymph nodes APCs showed a greater generation of Th1 cells than young APCs in antigen-presentation assays in vitro. Aged lacrimal glands, and draining nodes showed an accumulation of IFN-γ producing CD4+T cells, while Th-17 cells were present only in aged draining nodes. There was also an age-related increase in CD4+CXCR3+IFN-γ+ cells in the conjunctiva, nodes, and lacrimal glands while CD4+CCR6+IL-17A+ cells increased in the draining nodes of aged mice. Adoptive transfer of aged CD4+CXCR3+ cells into young, naive immunodeficient recipients caused greater goblet cell loss than young CD4+CXCR3+ donor cells. Our results demonstrate that age-associated changes in APCs are critical for the pathogenesis of age-related dry eye.

Lighting the anaerobic digestion process in rural areas: struvite from cattle manure digestate / Lighting the anaerobic digestion process in rural areas: struvite from cattle manure digestate

RESUMEN El objetivo de esta investigación fue obtener estruvita a partir del digerido de un digestor rural, alimentado con estiércol bovino. Con el fin de determinar las variables de operación para recuperar estruvita (iones PO4 3- y NH4+), se desarrolló un diseño de experimentos, en el cual se evaluó el efecto combinado de la relación molar de Mg2+:PO4 3- (1.5:1, 2.5:1 y 3.5:1), tiempo de reacción (10, 50 y 90 min) y velocidad de agitación (100, 450 y 800 rpm). Las condiciones determinadas como favorables fueron relación molar 1.5, tiempo de reacción 50 min y una velocidad de agitación de 450 rpm. Estos resultados muestran que la recuperación de fosfato más alta es alcanzada el contenido de Mg ya presente en el digerido de estiércol bovino (153 mg/L). Los porcentajes de recuperación obtenidos fueron 55 ± 4.94 % y 58 ± 7.72 % para NH4+ y PO4 3- respectivamente. La formación y composición de cristales de estruvita se confirmó mediante microscopía petrografía, microscopía electrónica de barrido (SEM) y radiación infrarroja. El rendimiento de estruvita obteniendo fue 295.75 mg/L de digerido utilizado.

ABSTRACT The aim of this research was recovery nutrients (PO4 3- and NH4+ ions) in form of struvite, used cattle manure digestate from low cost anaerobic digester. In order to determinate operating variables (Mg2+: PO4 3- molar ratio, reaction time and stirring speed) an experimental design was developed. Struvite crystal was identified by mean of petrographic microscopy and infrared radiation. The highest recovery rates of 55±4.94 % and 58±7.72 % for NH4+ and PO4 3-, respectively was achieved at 1.5 molar ratio, 50 minutes reaction time and 450 rpm stirring speed. Struvite yield was 295.75 mg/L. These results show that the highest phosphate recovery is achieved with the magnesium concentration (153 mg/L) contained in the cattle manure digestate.

RESUMO O intuito desta investigação foi obter estruvita partindo do digerido de um digestor rural, alimentado com esterco bovino. A fim de determinar as variáveis de operação para recuperar a estruvita (íons PO4 3" e NH4 +), foi desenvolvido um delineamento experimental, no qual foi avaliado o efeito combinado da razão molar de Mg2+: PO4 3" (1.5:1, 2.5:1 e 3.5: 1), tempo de reação (10, 50 e 90 min) e a velocidade de agitação (100, 450 e 800 rpm). A combinação de condições determinadas como favoráveis foram: relação molar de 1.5, tempo de reação de 50 minutos e velocidade de agitação de 450 rpm. Estes resultados indicam que a maior recuperação de fosfato é obtida com a concentração de magnésio (153 mg / L) contida no esterco bovino digerido. As porcentagens de recuperação obtidas foram de 55 ± 4.94% e 58 ± 7.72% para NH4+ e PO4 3" respectivamente. A formação e composição de cristais de estruvita foram confirmadas por meio de microscopia de petrografia, microscopia eletrônica de varredura (SEM) e radiação infravermelha. O rendimento da estruvita obtida foi de 295.75 mg /L de digerido utilizado.

Protective role of commensal bacteria in Sjögren Syndrome.

CD25 knock-out (CD25KO) mice spontaneously develop Sjögren Syndrome (SS)-like inflammation. We investigated the role of commensal bacteria by comparing CD25KO mice housed in conventional or germ-free conditions. Germ-free CD25KO mice have greater corneal barrier dysfunction, lower goblet cell density, increased total lymphocytic infiltration score, increased expression of IFN-γ, IL-12 and higher a frequency of CD4+IFN-γ+ cells than conventional mice. CD4+ T cells isolated from female germ-free CD25KO mice adoptively transferred to naive immunodeficient RAG1KO recipients caused more severe Sjögren-like disease than CD4+ T cells transferred from conventional CD25KO mice. Fecal transplant in germ-free CD25KO mice reversed the spontaneous dry eye phenotype and decreased the generation of pathogenic CD4+IFN-γ+ cells. Our studies indicate that lack of commensal bacteria accelerates the onset and severity of dacryoadenitis and generates autoreactive CD4+T cells with greater pathogenicity in the CD25KO model, suggesting that the commensal bacteria or their metabolites products have immunoregulatory properties that protect exocrine glands in the CD25KO SS model.

Impactos por cambio de uso de suelo en las áreas naturales protegidas de la región central de la Sierra Madre Oriental, México / Impact of land use cover change on protected natural areas in central region of Sierra Madre Oriental, Mexico

Resumen Los cambios en el uso de suelo y la cubierta vegetal, derivados de la expansión y extensión de асtividades antrópicas, generan impactos negativos en la biodiversidad y la provisión de servicios ecosistémicos, y contribuyen significativamente en los procesos de cambio climatico a nivel regional. Las Áreas Naturales Protegidas (ANP) representan un instrumento de política pública para hacer frente a las tendencias de cambio y transformación de los ecosistemas, además de permitir la conservación de los recursos. El objetivo de este estudio fue determinar el impacto potencial del cambio en el uso de suelo y la cobertura vegetal de las ANP de la región сеntral de la Sierra Madre Orientai (SMO), en México, a través del análisis espacial y la simulación de escenarios de cambio potencial. Se usaron imágenes satelitales para elaborar mapas de cambio en coberturas vegetales, entre los años 1989, 2000 y 2005, y con base en un conjunto de variables biofísicas y socioeconómicas, se simuló un escenario de cambio al 2025. Se determinó que la tasa de cambio de las cubiertas vegetales de la SMO en el periodo estudiado fue de 0.54 % en selvas, 0.22 % en bosques y 0.23 % en matorrales; y en las ANP fue de 0.34 % y 0.60 % para selvas y bosques, respectivamente. En este lapso se perdieron 1 578.26 ha de selvas, bosques y matorrales, al interior de las ANP. De mantenerse las tendencias actuales de cambio en el uso de la tierra, otras 4 542.17 ha estarán en riesgo de perderse en un futuro cercano. Los resultados indican que las ANP estudiadas están sometidas a presiones de cambio en el uso de la tierra, que amenazan la conservación del patrimonio natural que resguardan, por 10 que deberían rediseñarse las estrategias de manejo y monito reo a corto y mediano plazo.

Abstract Land use cover change, resulting from the expansion and extension of human activities, generates negative impact on biodiversity and the provision of ecosystem services, as well as contributing significantly to climate change processes at a regional level. Natural Protected Areas (NPA) represent a public policy instrument to address the trends of change and ecosystem transformation, while allowing the conservation of resources. The objective of this study was to determine the potential impact of the processes involved in land use cover change on the NPA as part of the central region at the Sierra Madre Oriental (SMO) in Mexico by using the special analysis and the scenery simulation of potential change. Satellite imagery was used to determine the changes in natural vegetation cover between 1989, 2000 and 2005 and, using a set of biophysical and socioeconomic variables, a change scenario was simulated for 2025. This study found that the rate of change of vegetation cover at the SMO over the research period was 0.54 % in tropical forests, 0.22 % in forests and 0.23 % in scrublands, while those in NPA were 0.34 % and 0.60 % in tropical forests and forests respectively; 1 578.26 ha of tropical semi-deciduous temperate forest and scrublands were lost from the NPA. If the current land use trends change continues, another 4 542.17 ha are likely to be modified in the future. These results indicate that NPA under study are subject to the pressures of land use change that threaten the natural heritage under protection and that, therefore, management strategies and monitoring need to be redesigned in the short and medium term.