Association of the superior semicircular canal and tegmen tympani dehiscences and its relationship with the pneumatisation of the temporal bone.

PURPOSE: To analyse the degree of pneumatisation of the temporal bone when there is an association between dehiscence of the superior semicircular canal and dehiscence of the tegmen tympani. MATERIALS AND METHODS: We analysed a retrospective CT study of 124 selected cases. A single inclusion criterion was applied: the presence of a dehiscence of the tegmen tympani. On the other hand, the degree of temporal pneumatisation was assessed by axial and coronal planes, and has been divided into the following grades O, I, II and III, according to the status and relationship of the mastoid, the bony labyrinth, the petrous segment of the carotid canal and sigmoid sinus. RESULTS: Of the 124 cases studied, 35 (28.2%) presented both dehiscences. In 26 of the 35 (47.3%), grade II pneumatisation, 4 (14,8%), grade I, and 5 (11,9%) grade III was observed, with a statistically significant relationship (p < 0.001). On the other hand, we did not find a significant relationship when relating both dehiscences in any age or sex group. However, when relating the degree of pneumatisation to sex, among those with grade III pneumatisation, the proportion of men (52.4%) was significantly higher than that of women (47.6%) (p = 0.017). CONCLUSION: We have detected a statistically significant relationship between the coexistence of grade II pneumatisation and the presence of both dehiscences in the temporal bone.

The importance of thyroid hormone signaling during early development: Lessons from the zebrafish model.

The zebrafish is an optimal experimental model to study thyroid hormone (TH) involvement in vertebrate development. The use of state-of-the-art zebrafish genetic tools available for the study of the effect of gene silencing, cell fate decisions and cell lineage differentiation have contributed to a more insightful comprehension of molecular, cellular, and tissue-specific TH actions. In contrast to intrauterine development, extrauterine embryogenesis observed in zebrafish has facilitated a more detailed study of the development of the hypothalamic-pituitary-thyroid axis. This model has also enabled a more insightful analysis of TH molecular actions upon the organization and function of the brain, the retina, the heart, and the immune system. Consequently, zebrafish has become a trendy model to address paradigms of TH-related functional and biomedical importance. We here compilate the available knowledge regarding zebrafish developmental events for which specific components of TH signaling are essential.

Interdependence between the aerobic degradation of BPA and readily biodegradable substrates by activated sludge in semi-continuous reactors.

The objective of the present work was to analyze the interrelationship between the aerobic degradation of BPA and readily biodegradable substrates by activated sludge (AS) in semi-continuous reactors (SCRs). AS were obtained from three SCRs fed with glucose, acetate or peptone. AS from these reactors were used as inocula for three SCRs that were fed with each biogenic substrate, and for three SCRs that were fed with the biogenic substrate and BPA. In all cases, dissolved organic carbon (DOC), BPA, total suspended solids (TSS) and respirometric measurements were performed. Although BPA could be removed in the presence of all the tested substrates, AS grown on acetate exhibited the longest acclimation to BPA. Reactors fed with peptone attained the lowest TSS concentration; however, these AS had the highest specific BPA degradation rate. Specific DOC removal rates and respirometric measurements demonstrated that the presence of BPA had a negligible effect on the removal of the tested substrates. A mathematical model was developed to represent the evolution of TSS and DOC in the SCRs as a function of the operation cycle. Results suggest that the main effect of BPA on AS was to increase the generation of microbial soluble products. This work helps to understand the relationship between the biodegradation of BPA and readily biodegradable substrates.

Monitoring the biodegradability of bisphenol A and its metabolic intermediates by manometric respirometry tests.

As a result of its wide usage in the production of polycarbonate plastics and epoxy resins, bisphenol A (BPA) is commonly detected in wastewaters. Recently, BPA became a major concern because its adverse effects as an endocrine disruptor. In this work, the biodegradation kinetics of BPA and its metabolic intermediates 4-hydroxyacetophenone (4HAP), 4-hydroxybenzaldehyde (4HB) and 4-hydroxybenzoic acid (4HBA) by BPA-acclimated activated sludge was studied using manometric respirometry (BOD) tests. For all the tested compounds, BOD curves exhibited two phases. In the first one, a fast increase of the oxygen consumption (OC) due to the active oxidation of the substrate was obtained. Then, when the substrate was exhausted, the endogenous respiration produced a slower increase of OC. A standard Monod-model with biomass growth was used to represent the OC profiles as a function of time. For all the tested compounds, a good agreement between the proposed model and the experimental data was obtained. According to their biodegradation rates, the tested compounds can be ordered as follows: BPA < 4HAP â‰ª 4HB < 4HBA. Because the oxidation rate of BPA by BPA-acclimated activated sludge limits the rate of the whole biodegradation pathway, the accumulation of metabolic intermediates 4HAP, 4HB, and 4HBA would be negligible. To calculate the dissolved oxygen (DO) concentration (C) during the BOD tests, the oxygen transfer coefficient (kLa) of the BOD bottles was obtained using the sulfite method. Finally, a simple procedure to calculate the minimum DO concentration (Cmin) based on BOD data was developed. Calculation results demonstrated that under the tested conditions, C values were high enough as not to be the limiting substrate for the microbial growth.

Simultaneous biodegradation of bisphenol A and a biogenic substrate in semi-continuous activated sludge reactors.

In this work, the simultaneous degradation of BPA and cheese whey (CW) in semi-continuous activated sludge reactors was studied. The acclimation process and microbial growth on BPA, CW and BPA + CW were analyzed. In addition, the effect of increasing CW concentration on the BPA degradation by acclimated activated sludge was also studied. In order to reduce the factors involved in the analysis of the simultaneous degradation of BPA and CW, the effect of bisphenol A (BPA) on activated sludge not previously exposed to BPA (native activated sludge) was studied. Results demonstrate that BPA concentrations lower than 40 mg l(-1) had a negligible effect on the growth of native activated sludge. In the semi-continuous reactors, the presence of CW increased the acclimation time to 40 mg l(-1) of BPA. Once the capability of degrading BPA was acquired, the removal of BPA was not affected by the presence of CW. Increasing the CW concentration did not affect the removal of BPA by the acclimated activated sludge. Additionally, the CW consumption was not modified by the presence of BPA. Kinetic and stoichiometric coefficients reported in the present work can be useful in developing mathematical models to describe the simultaneous aerobic biodegradation of a biogenic substrate, such as CW, and BPA by activated sludge.

Differential effects of 3,5-T2 and T3 on the gill regeneration and metamorphosis of the Ambystoma mexicanum (axolotl).

Thyroid hormones (THs) regulate tissue remodeling processes during early- and post-embryonic stages in vertebrates. The Mexican axolotl (Ambystoma mexicanum) is a neotenic species that has lost the ability to undergo metamorphosis; however, it can be artificially induced by exogenous administration of thyroxine (T4) and 3,3',5-triiodo-L-thyronine (T3). Another TH derivative with demonstrative biological effects in fish and mammals is 3,5-diiodo-L-thyronine (3,5-T2). Because the effects of this bioactive TH remains unexplored in other vertebrates, we hypothesized that it could be biologically active in amphibians and, therefore, could induce metamorphosis in axolotl. We performed a 3,5-T2 treatment by immersion and observed that the secondary gills were retracted, similar to the onset stage phenotype; however, tissue regeneration was observed after treatment withdrawal. In contrast, T4 and T3 immersion equimolar treatments as well as a four-fold increase in 3,5-T2 concentration triggered complete metamorphosis. To identify the possible molecular mechanisms that could explain the contrasting reversible or irreversible effects of 3,5-T2 and T3 upon gill retraction, we performed a transcriptomic analysis of differential expression genes in the gills of control, 3,5-T2-treated, and T3-treated axolotls. We found that both THs modify gene expression patterns. T3 regulates 10 times more genes than 3,5-T2, suggesting that the latter has a lower affinity for TH receptors (TRs) or that these hormones could act through different TR isoforms. However, both TH treatments regulated different gene sets known to participate in tissue development and cell cycle processes. In conclusion, 3,5-T2 is a bioactive iodothyronine that promoted partial gill retraction but induced full metamorphosis in higher concentrations. Differential effects on gill retraction after 3,5,-T2 or T3 treatment could be explained by the activation of different clusters of genes related with apoptosis, regeneration, and proliferation; in addition, these effects could be initially mediated by TRs that are expressed in gills. This study showed, for the first time, the 3,5,-T2 bioactivity in a neotenic amphibian.

Chronic atrazine exposure increases the expression of genes associated with GABAergic and glutamatergic systems in the brain of male albino rat.

The herbicide atrazine (ATR; 2-chloro-4-ethylamino-6-isopropylamino-s-triazine) is widely used to destroy grasses and broadleaf weeds in crops and some fruits. Studies in rodents have shown that acute, repeated or chronic exposure to ATR is associated with alterations in the nigrostriatal dopaminergic pathway, whereas its effects on GABAergic and glutamatergic pathways have only recently been reported. Sprague-Dawley male rats were exposed daily to 1 or 10 mg ATR/kg of BW for 13 months to evaluate the ATR effects on GABAergic and glutamatergic systems. At the end of the ATR treatment, the levels of mRNA of several genes involved in the production, vesiculation, reuptake, and receptors of GABA and Glu in the striatum (STR), nucleus accumbens (NAcc), prefrontal cortex (PFC), ventral midbrain (vMID) and hippocampus (HIPP) were evaluated by absolute qPCR. For the GABAergic genes, increased expression of GAD67 and Slc32a1 in STR and/or vMID in rats exposed to 1 and/or 10 mg ATR were detected. With regard to the expression of genes involved in the glutamatergic system, Slc17a6 and Grin1 in HIPP of rats exposed to 1 and/or 10 mg ATR, increased as was Gria1 in STR and PFC in the group exposed to 1 mg ATR. In the same fashion, Slc1a3 expression and MGLUR1 increased in STR of rats exposed to 1 and 10 mg ATR groups. The expression of the glutaminases gls (variants 1 and 2) was greater in STR, NAcc, HIPP, and PFC of rats exposed to 1 and/or 10 mg ATR. These findings show that the GABAergic and, especially glutamatergic systems are targets of ATR exposure.

Biological removal of hexavalent chromium: evaluation of the metabolic activity of native and Cr(VI)-acclimated activated sludge using a respirometric method.

Hexavalent chromium becomes in one of the tops internationally concern environmental issues due to its wide usage in several industrial activities. There are two stable oxidation states of chromium in the environment which differ significantly on its toxicity; Cr(III) has lower solubility, mobility and lesser biological toxicity in comparison with Cr(VI). While Cr(VI) is a well-known carcinogen, Cr(III) is an essential dietary element. For this reason, most technologies focus attention on the reduction of Cr(VI) to Cr(III). On this context, the ability of microorganisms to reduce Cr(VI) to Cr(III) has gained attention. The objectives of the present work were to analyze the effect of Cr(VI) on the activated sludge community in a continuous reactor, and to evaluate the differences on the metabolic activity of native (NAS) and Cr(VI)-acclimated activated sludge (CrAAS) using a respirometric method. Results showed that the activated sludge community had the capability to acclimate to the presence of Cr(VI). On the other hand, the increase of the initial Cr(VI) concentration from 0 to 100 mgCr/L leads to a decrease in the specific exogenous respiration rate (qEx ) values, but this reduction was more noticeably in the case of NAS in comparison with CrAAS. The respirometric curves were well described by the proposed mathematical model. It was concluded that the CrAAS tolerated a Cr(VI) concentration about one order of magnitude higher than NAS, which was positively reflected in the respiration rate first-order decay constant (kd ), the specific maximum exogenous respiration rate (qExm ), and the observed oxidation coefficient (YO/S ) values.

Influence of Baseline Physical Activity as a Modifying Factor on COVID-19 Mortality: A Single-Center, Retrospective Study.

INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes a severe respiratory disease with a 3% global mortality. In the absence of effective treatment, controlling of risk factors that predispose to severe disease is essential to reduce coronavirus disease 2019 (COVID-19) mortality. Large observational studies suggest that exercise can reduce the risk of all-cause and disease-specific mortality. The aim of this study was to analyze the influence of the baseline physical activity level on COVID-19 mortality METHODS: This is a retrospective cohort study that included patients between 18 and 70 years old, diagnosed with COVID-19 and hospitalized in our center between February 15 and April 15, 2020. After discharge all the patients included in the study were contacted by telephone. Baseline physical activity level was estimated using the Rapid Assessment of Physical Activity Scale questionnaire and patients were divided into two groups for comparison: sedentary patients (group 1) and active patients (group 2). RESULTS: During the study period 552 patients were admitted to our hospital and met the inclusion criteria. Global mortality in group 1 was significantly higher than in group 2 (13.8% vs 1.8%; p < 0.001). Patients with a sedentary lifestyle had increased COVID-19 mortality independently of other risk factors previously described (hazard ratio 5.91 (1.80-19.41); p = 0.003). CONCLUSION: A baseline sedentary lifestyle increases the mortality of hospitalized patients with COVID-19. This finding may be of great utility in the prevention of severe COVID-19 disease.

Mapping biogeochemically active zones in landfills with induced polarization imaging: The Heferlbach landfill.

In this study, we investigate the applicability of the Induced Polarization (IP) imaging method to discriminate between biogeochemically active and inactive areas of a landfill. The elevated amount of degradable organic carbon in landfills results in the development of biogeochemical hot-spots associated with high rates of microbial activity and the generation of landfill gas and leachate as metabolic products. Our results demonstrate that the electrical conductivity is mainly sensitive to the increase in the fluid conductivity associated to leachate production and migration. Whereas images of the polarization effect, expressed in terms of the imaginary component (σ″) or the phase of the complex conductivity (ϕ), reveal the potential to characterize variations in the architecture and biogeochemical activity of the landfill. Correspondingly, biogeochemically active zones (leachable TOC contents above 1500 mg/kg dry waste) are related to high polarization values (σ″ > 10 mS/m, ϕ > 40 mrads), whereas low leachable TOC contents (<300 mg/kg dry waste) in the inactive areas are characterized by low polarization values (σ″ < 1 mS/m, 10 < Ï• < 25). Additionally, landfill sections corresponding to construction and demolition waste (CDW), associated to negligible TOC content, exhibit the lowest polarization response (σ″ < 0.1 mS/m, ϕ < 15). We prove that IP imaging is a well-suited method for landfill investigations that permits an improved characterization of landfill geometry, variation in waste composition, and the discrimination between biogeochemically active and inactive zones.

Bone Marrow Culture Yield for the Diagnosis of Opportunistic Diseases in Patients with AIDS and Disseminated Kaposi Sarcoma.

BACKGROUND: Disseminated Kaposi sarcoma (DKS) is present in patients with advanced HIV infection in whom co-infection with other opportunistic pathogens can occur. Bone marrow (BM) aspirate and biopsy comprise a robust diagnostic tool in patients with fever, cytopenias, and abnormal liver tests. However, the yield in patients with DKS has not been determined. OBJECTIVE: The aim of this study was to evaluate the utility of BM aspirate and biopsy in patients with DKS. METHODS: We included 40 male patients with a recent diagnosis of DKS. BM aspirate and biopsy was performed as part of the workup to rule out co-infections. RESULTS: In four patients, Mycobacterium avium complex (MAC) was recovered from culture. In other four patients, intracellular yeasts were observed in the Grocott stain, diagnosed as Histoplasma. The yield of BM was calculated in 20%. Only 12 patients (30%) had fever and 11 (27.5%) had pancytopenia. Alkaline phosphatase (ALP) above normal values and C-reactive protein (CRP) were higher in patients with positive results for BM than in those with negative results (63% vs. 21.9%, and 3.0 vs. 1.2 mg/L; p = 0.03 in both comparisons). No differences were found when complete blood-count abnormalities were compared. CONCLUSION: We recommend performing a BM aspirate for stains, culture, and biopsy in all HIV patients with DKS, as this will permit the early diagnosis of co-infections and prevent further complications in those who receive chemotherapy.

International collaboration for pediatric oncology nursing leadership: Nicaragua and Canada.

In 2005, with financial support from the Pediatric Oncology Group of Ontario, a pilot nursing leadership project linked pediatric oncology nurses from Canada with nurses at the La Mascota Hospital in Managua, Nicaragua. Following consultation with the pediatric oncology team in Nicaragua, a program was developed to strengthen clinical nursing leadership in a clinical setting through continuing education. The nurses believed that care of the patient and family improved due to the increased leadership skills of nurses in the unit and as the profile and credibility of nurses as peers in the health care team became evident. Providing nurses with the autonomy and financing for a project related directly to nursing care represented an important development for leadership in the profession.

3,5-T2 and 3,3',5-T3 Regulate Cerebellar Thyroid Hormone Signalling and Myelin Molecular Dynamics in Tilapia.

In contrast to mammalian adults, myelination in teleosts occurs throughout their lifespan and most of the progenitor cells are originated in the cerebellum. To understand the role that thyroid hormones (THs) play in juvenile cerebellar myelination in teleosts, we identified and localised the expression of genes involved in TH signalling (mct8, oatp1c1, dio2, dio3, thraa and l-thrb1) and analysed the effects of the two bioactive THs, T2 and T3, upon their regulation, as well as upon some structural components of the myelination process. Ex vivo approaches using organotypic cerebellar cultures followed by FISH and qPCR showed gene-specific localisation and regulation of TH signalling genes in the cerebellar nuclei. In vivo approaches using methimazole (MMI)-treated juvenile tilapias replaced with low doses of T3 and T2 showed by immunofluorescence that myelin fibres in the cerebellum are more abundant in the granular layer and that their visible size is reduced after MMI treatment but partially restored with TH replacement, suggesting that low doses of TH promote the re-myelination process in an altered condition. Together, our data support the idea that T2 and T3 promote myelination via different pathways and prompt T2 as a target for further analysis as a promising therapy for hypomyelination.

Super large cardiac hemangioma in right atrium and inferior vena cava: case report.

BACKGROUND: Cardiac hemangiomas are rare cardiac neoplasia usually diagnosed in autopsies, from being asymptomatic to debuting with sudden death. The largest hemangioma published in the literature is of 130 mm size, we present the following case of a successful cardiac hemangioma excision of 280 × 35 mm in size, diagnosed due to recurrent cardiac symptoms. CASE PRESENTATION: A 48-year-old female patient, Jehovah's Witness, with no previous diagnoses, is admitted due to recurrent syncopal episodes in the previous months. A transthoracic echocardiogram diagnosed a tumor in the right atrium and inferior vena cava producing a diastolic right ventricular, with preservation of the left ventricular ejection fraction at 55%. Given the high mortality risk, a surgical intervention was performed immediately. Successful excision was completed confirming a 280 × 35 mm mass without any complications, consistent with hemangioma on histopathology. Postoperative recovery showed no recurrence or complications. CONCLUSIONS: Cardiac hemangiomas are rare and its clinical course can be varied from patient to patient. We present excision of a large cardiac mass with a high mortality risk due to its size and the patient's spiritual beliefs.

Modelling Cr(VI) removal by a combined carbon-activated sludge system.

The combined carbon-activated sludge process has been proposed as an alternative to protect the biomass against toxic substances in wastewaters; however, the information about the effect of powdered-activated carbon (PAC) addition in activated sludge reactors for the treatment of wastewaters containing Cr(VI) is limited. The objectives of the present study were: (a) to evaluate the removal of hexavalent chromium by (i) activated sludge microorganisms in aerobic batch reactors, (ii) powdered-activated carbon, and (iii) the combined action of powdered-activated carbon and biomass; (b) to propose mathematical models that interpret the experimental results. Different Cr(VI) removal systems were tested: (S1) biomass (activated sludge), (S2) PAC, and (S3) the combined activated carbon-biomass system. A Monod-based mathematical model was used to describe the kinetics of Cr(VI) removal in the system S1. A first-order kinetics with respect to Cr(VI) and PAC respectively, was proposed to model the removal of Cr(VI) in the system S2. Cr(VI) removal in the combined carbon-biomass system (S3) was faster than both Cr(VI) removal using PAC or activated sludge individually. Results showed that the removal of Cr(VI) using the activated carbon-biomass system (S3) was adequately described by combining the kinetic equations proposed for the systems S1 and S2.

Lobectomías robóticas y cáncer de pulmón. Experiencia inicial en nuestro centro / Robotic lobectomies and lung cancer. Initial experience in our center

Objetivo: Analizar la seguridad y factibilidad en términos de resultados obtenidos en las primeras lobectomías robóticas realizadas en nuestro centro. Metodología: Estudio prospectivo desde mayo hasta diciembre de 2021 en 13 pacientes (11 hombres y 2 mujeres, edad media 59 años) con carcinoma de pulmón en estadios precoces tributarios de lobectomía robótica.Se utilizó el sistema da Vinci Xi con cuatro puertos y uno asistente. Resultados: Se realizaron 13 lobectomías robóticas. La conversión a cirugía videoasistida fue necesaria en 2 pacientes (15,4%). Se produjeron complicaciones en 3 pacientes (23%). La mediana de tiempo quirúrgico fue180 minutos [IQR 150-210]. La mediana de estancia hospitalaria fue de 4 días [IQR 3 - 6]. La mediana de duración del drenaje pleural fue de 4 días [IQR3 - 6]. La histología predominante fue carcinoma epidermoide en5 pacientes (39%). La media de ganglios linfáticos resecados fue de 15 (IC 95%: 11 - 19) y la de estaciones ganglionares de 5 (IC 95%: 4 - 5). No hubo mortalidad postoperatoria. El estadio postquirúrgico fue IA2 en 4 pacientes (31%), IB en 3 (23%), IIB en 2 (15%), y IIIA en 1 (7%). No se establecen diferencias estadísticamente significativas entre el IMC, el lóbulo resecado y la presencia de complicaciones (p = 0,5; p = 0,2), ni entre el número de ganglios resecados/número de estaciones ganglionares, y el estadio tumoral (p = 0,4; p = 0,9). Conclusiones: La lobectomía robótica con linfadenectomía hiliomediastínica es factible y segura. Es necesaria mayor experiencia y seguimiento a largo plazo para una adecuada evaluación de los resultados postoperatorios, la eficacia oncológica, y la comparación con las vías de abordaje convencionales. (AU)

Objectives: analyze the safety and feasibility in terms of results obtained in the first robotic lobectomies performed in our center. Method: prospective study from May to December 2021 in 13 patients (11 men and 2 women, mean age 59 years) with lung carcinoma in early stages requiring robotic lobectomy. The da Vinci Xi system was used with four ports and one assistant. Results: 13 robotic lobectomies were performed. Conversion to video-assisted surgery was necessary in 2 patients (15.4%). Complications occurred in 3 patients (23%). The median surgical time was 180 minutes [IQR 150-210]. The median hospital stay was 4 days [IQR 3 - 6]. The median duration of pleural drainage was 4 days [IQR3 - 6]. The predominant histology was squamous cell carcinoma in 5 patients (39%). The mean number of lymph nodes resected was 15 (95% CI: 11 - 19) and the number of lymph nodes resected was 5 (95% CI: 4 - 5). There was no postoperative mortality. The postsurgical stage was IA2 in 4 patients (31%), IB in 3 (23%), IIB in 2 (15%), and IIIA in 1 (7%). No statistically significant differences were established between BMI, the resected lobe and the presence of complications (p = 0.5; p = 0.2), nor between the number of resected lymph nodes/number of lymph node stations, and the tumor stage ( p = 0.4; p = 0.9).Conclusions: robotic lobectomy with hiliomediastinal lymphadenectomy is feasible and safe. Greater experience and long-term follow-up are necessary for an adequate evaluation of postoperative results, oncological efficacy, and comparison with conventional approaches. (AU)

Interleukin 18 and periodontal disease.

Cytokines are of major importance in periodontal disease progression. It is generally agreed that control of the Th1/Th2 balance is central to the immunoregulation of periodontal disease. There is increasing evidence in humans that the stable periodontal lesion is mediated by Th1 cells, while the progressive lesion sees a shift toward Th2 cells. Equally, there is conflicting evidence, mainly in animal models, that bone loss is mediated by Th1 responses, and that Th2 responses are protective. In the presence of IL-12, IL-18 induces Th1 responses while, in the absence of IL-12, it promotes Th2 responses. It is clear, therefore, that since IL-18 has the ability to induce either Th1 or Th2 differentiation, it becomes important to consider its role in periodontal disease. This review endeavors to give an overview of this cytokine and its relevance for periodontal disease.

Differential transcriptome regulation by 3,5-T2 and 3',3,5-T3 in brain and liver uncovers novel roles for thyroid hormones in tilapia.

Although 3,5,3'-triiodothyronine (T3) is considered to be the primary bioactive thyroid hormone (TH) due to its high affinity for TH nuclear receptors (TRs), new data suggest that 3,5-diiodothyronine (T2) can also regulate transcriptional networks. To determine the functional relevance of these bioactive THs, RNA-seq analysis was conducted in the cerebellum, thalamus-pituitary and liver of tilapia treated with equimolar doses of T2 or T3. We identified a total of 169, 154 and 2863 genes that were TH-responsive (FDR < 0.05) in the tilapia cerebellum, thalamus-pituitary and liver, respectively. Among these, 130, 96 and 349 genes were uniquely regulated by T3, whereas 22, 40 and 929 were exclusively regulated by T2 under our experimental paradigm. The expression profiles in response to TH treatment were tissue-specific, and the diversity of regulated genes also resulted in a variety of different pathways being affected by T2 and T3. T2 regulated gene networks associated with cell signalling and transcriptional pathways, while T3 regulated pathways related to cell signalling, the immune system, and lipid metabolism. Overall, the present work highlights the relevance of T2 as a key bioactive hormone, and reveals some of the different functional strategies that underpin TH pleiotropy.

Canada's International Development Research Centre's eco-health projects with Latin Americans: origins, development and challenges.

BACKGROUND: Since its founding in 1970, Canada's International Development Research Centre (IDRC) has supported research by concerned Latin American researchers on environments and human health relationships. Framing of such relationships has changed through different periods. METHODS: Participant observation, bibliographic searches, document review, and interviews with key IDRC staff. FINDINGS: From the early years of multiple different projects, IDRC developed more focussed interest in tropical diseases, pesticides, agriculture and human health in the 1980s. The United Nations Conference on Sustainable Development in the early 1990s gave impetus to examination of links between ecosystems and human health or "EcoHealth". Projects in Latin America built on earlier work but extended it in methods (transdisciplinarity, community participation, gendered approach) and scope (broader land use and development paradigm issues tackled). A key IDRC-funded activity in Latin America was "EcoSalud", an Ecuadorian effort, which has worked with farming communities, agricultural researchers, health practitioners and local politicians to advance integrated pest management, better recognize and treat poisonings and improve pesticide-related policies. ONGOING CHALLENGES INCLUDE: mobilizing sufficient resources for the primary prevention focus of EcoHealth activities when primary care infrastructure remains stretched, promoting micro-level change in diverse communities and ecosystems, and addressing power structures at the global level that profoundly affect environmental change.