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Current treatments for KRAS-mutant colorectal cancers (CRCs) are often limited by cellular plasticity and rewiring responses. Here we describe a promising therapeutic strategy that simultaneously targets epigenetic and oncogenic signals. Specifically, we show that inhibitors of the histone methyltransferase, EZH2, synergize with various RAS pathway inhibitors and promote dramatic tumor regression in vivo. Together these agents cooperatively suppress WNT-driven transcription and drive CRCs into a more differentiated cell state by inducing the Groucho/TLE corepressor, TLE4, along with a network of WNT pathway inhibitors and intestinal differentiation proteins. However, these agents also induce the pro-apoptotic protein BMF, which subsequently kills these more differentiated cells. Accordingly, cell death can be prevented by activating ß-catenin, blocking differentiation, or by ablating BMF expression. Collectively, these studies reveal a new therapeutic approach for treating KRAS-mutant CRCs and illustrate a critical convergence of EZH2 and RAS on oncogenic WNT signals, intestinal differentiation, and apoptosis.
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Infections by Staphylococcus aureus have been treated historically with ß-lactam antibiotics. However, these antibiotics have become obsolete in methicillin-resistant S. aureus by acquisition of the bla and mec operons. The presence of the ß-lactam antibiotic is detected by the sensor domains of BlaR and/or MecR, and the information is transmitted to the cytoplasm, resulting in derepression of the antibiotic-resistance genes. We hypothesized that inhibition of the sensor domain would shut down this response system, and ß-lactam susceptibility would be restored. An in silico search of 11 million compounds led to a benzimidazole-based hit and, ultimately, to the boronate 4. The X-ray structure of 4 is covalently engaged with the active-site serine of BlaR. Compound 4 potentiates by 16- to 4,096-fold the activities of oxacillin and of meropenem against methicillin-resistant S. aureus strains. The combination of 4 with oxacillin or meropenem shows efficacy in infected mice, validating the strategy.
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Peptidoglycan is a major constituent of the bacterial cell wall. Its integrity as a polymeric edifice is critical for bacterial survival and, as such, it is a preeminent target for antibiotics. The peptidoglycan is a dynamic crosslinked polymer that undergoes constant biosynthesis and turnover. The soluble lytic transglycosylase (Slt) of Pseudomonas aeruginosa is a periplasmic enzyme involved in this dynamic turnover. Using amber-codon-suppression methodology in live bacteria, we incorporated a fluorescent chromophore into the structure of Slt. Fluorescent microscopy shows that Slt populates the length of the periplasmic space and concentrates at the sites of septation in daughter cells. This concentration persists after separation of the cells. Amber-codon-suppression methodology was also used to incorporate a photoaffinity amino acid for the capture of partner proteins. Mass-spectrometry-based proteomics identified 12 partners for Slt in vivo. These proteomics experiments were complemented with in vitro pulldown analyses. Twenty additional partners were identified. We cloned the genes and purified to homogeneity 22 identified partners. Biophysical characterization confirmed all as bona fide Slt binders. The identities of the protein partners of Slt span disparate periplasmic protein families, inclusive of several proteins known to be present in the divisome. Notable periplasmic partners (KD < 0.5 µM) include PBPs (PBP1a, KD = 0.07 µM; PBP5 = 0.4 µM); other lytic transglycosylases (SltB2, KD = 0.09 µM; RlpA, KD = 0.4 µM); a type VI secretion system effector (Tse5, KD = 0.3 µM); and a regulatory protease for alginate biosynthesis (AlgO, KD < 0.4 µM). In light of the functional breadth of its interactome, Slt is conceptualized as a hub protein within the periplasm.
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Proteínas Bacterianas , Pseudomonas aeruginosa , Pseudomonas aeruginosa/enzimología , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Periplasma/metabolismo , Periplasma/enzimología , Proteínas Periplasmáticas/metabolismo , Proteínas Periplasmáticas/genética , Proteínas Periplasmáticas/química , Glicosiltransferasas/metabolismo , Glicosiltransferasas/genética , Glicosiltransferasas/química , Peptidoglicano/metabolismo , Peptidoglicano/químicaRESUMEN
BACKGROUND: Key populations are disproportionately affected by HIV, viral hepatitis (VH), and sexually transmitted infections (STIs) and face barriers to care. Peer navigation programs are widely used, but evidence supporting their use has not been synthesized. SETTING: Peer navigation programs for sex workers, men who have sex with men, people who inject drugs, prisoners, and trans and gender diverse people globally. METHODS: To inform World Health Organization guidelines, we conducted a systematic review of effectiveness, values and preferences, and cost studies published between January 2010 and May 2021. We searched CINAHL, PsycINFO, PubMed, and EMBASE; screened abstracts; and extracted data in duplicate. The effectiveness review included randomized controlled trials and comparative observational studies evaluating time to diagnosis or linkage to care, treatment initiation, treatment retention/completion, viral load, cure, or mortality. We assessed risk of bias and summarized findings in GRADE evidence profiles. Values and preferences and cost data were summarized descriptively. RESULTS: Four studies evaluated the effectiveness of peer navigators for key populations. All were focused on HIV; none were designed for VH or STIs. These studies showed mixed effects on linkage to care, treatment retention/completion, and viral load; no studies measured treatment initiation, cure, or mortality. Two values and preferences studies with community-based organization staff and health workers suggested peer navigators for key populations were acceptable and valued, although continued challenges remained. No cost studies were identified. CONCLUSIONS: Although limited, available studies provide moderate certainty evidence for benefits of HIV/VH/STI peer navigation programs for key populations. Further evaluations are needed.
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Infecciones por VIH , Cumplimiento de la Medicación , Retención en el Cuidado , Humanos , Masculino , Infecciones por VIH/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Observacionales como Asunto , Poblaciones VulnerablesRESUMEN
INTRODUCTION: COVID-19 vaccination hesitancy is prevalent in underserved communities, and family medicine clinics can combat hesitancy with vaccine education. However, due to general misinformation, physicians hesitate to educate patients because doing so can create conflict. METHODS: A series of resident-run, team-based quality improvement projects were conducted at a federally qualified health center every 4 months between June 2021 and May 2022. First, staff documentation of vaccine status was addressed. Second, physician and staff education about COVID-19 vaccines was completed along with motivational interview training to avoid conflict with patients. Third, patient COVID-19 vaccine education was addressed. RESULTS: After Cycle 1, COVID-19 vaccine documentation status increased the number of patients who completed the vaccination series from 1% to 22%. Cycle 2 showed an increase in COVID-19 vaccination rate after health care team education. This reflected an increase from 35% to 76% of residents reporting that they discussed COVID-19 vaccines with unvaccinated patients after the intervention. Cycle 3 fought vaccine misinformation by educating patients. Most patients heard information about COVID-19 vaccines from friends and family (95%), social media (90%), and the news (80%). Physician confidence in providing COVID-19 vaccine education to patients increased from 2.8 (< somewhat confident) to 4.3 (moderately confident) out of 5 over 3 plan-do-study-act cycles. DISCUSSION: Vaccination rates were tracked alongside physician surveys regarding the experience of offering the vaccine to patients. Vaccination rates steadily increased over time, and physicians became more confident in COVID-19 vaccine discussions with patients. CONCLUSION: Primary care physicians are needed to approach public health concerns, such as vaccination completion, but ongoing education is also needed to promote confidence in health care pathways.
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COVID-19 , Vacunas , Humanos , Vacunas contra la COVID-19/uso terapéutico , COVID-19/prevención & control , Escolaridad , Vacunación , Educación en SaludRESUMEN
The 11 lytic transglycosylases of Pseudomonas aeruginosa have overlapping activities in the turnover of the cell-wall peptidoglycan. Rare lipoprotein A (RlpA) is distinct among the 11 by its use of only peptidoglycan lacking peptide stems. The spatial localization of RlpA and its interactome within P. aeruginosa are unknown. We employed suppression of introduced amber codons at sites in the rlpA gene for the introduction of the unnatural-amino-acids Νζ -[(2-azidoethoxy)carbonyl]-l-lysine (compound 1) and Nζ -[[[3-(3-methyl-3H-diazirin-3-yl)propyl]amino]carbonyl]-l-lysine (compound 2). In live P. aeruginosa, full-length RlpA incorporating compound 1 into its sequence was fluorescently tagged using strained-promoted alkyne-azide cycloaddition and examined by fluorescence microscopy. RlpA is present at low levels along the sidewall length of the bacterium, and at higher levels at the nascent septa of replicating bacteria. In intact P. aeruginosa, UV photolysis of full-length RlpA having compound 2 within its sequence generated a transient reactive carbene, which engaged in photoaffinity capture of neighboring proteins. Thirteen proteins were identified. Three of these proteins-PBP1a, PBP5, and MreB-are members of the bacterial divisome. The use of the complementary methodologies of non-canonical amino-acid incorporation, photoaffinity proximity analysis, and fluorescent microscopy confirm a dominant septal location for the RlpA enzyme of P. aeruginosa, as a divisome-associated activity. This accomplishment adds to the emerging recognition of the value of these methodologies for identification of the intracellular localization of bacterial proteins.
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Lipoproteína(a) , Pseudomonas aeruginosa , Lipoproteína(a)/metabolismo , Codón de Terminación/metabolismo , Peptidoglicano/metabolismo , Lisina/metabolismoRESUMEN
Cannabidiol (CBD) is a non-psychoactive cannabinoid purported to reduce symptoms of discomfort. Individuals are now using CBD to treat symptoms of multiple sclerosis, seizures, and chronic pain. Animal models indicate that CBD may be effective at reducing inflammation post fatiguing exercise. However, little evidence is available to evaluate these findings in humans. Therefore, the purpose of this investigation was to evaluate the impact of two doses of CBD oil on inflammation (IL-6), performance, and pain after an eccentric loading protocol. Participants (n = 4) participated in three conditions (placebo, low dose, and high dose), in this randomized, counterbalanced design. Each condition took 72 hours to complete, with a 1-week washout period between conditions. At the beginning of each week, participants were subjected to a loading protocol of six sets of ten eccentric only repetitions in the single-arm bicep curl. Participants consumed capsules of either a placebo, low dose (2mg/kg) or high dose (10mg/kg) of CBD oil immediately following the session and continued every twelve hours for 48 hours. Venipunctures were taken before exercise and repeated at 24, 48, and 72 hours post exercise. Blood samples were centrifuged for 15 minutes in gel and lithium heparin vacutainers. Plasma was separated from cells and stored at -80° until analysis. Samples were analyzed using an immunometric assay for IL-6 (ELISA). Data were analyzed using a three (condition) by four (time) repeated measure ANOVA. There were no differences in inflammation between conditions (F(2,6) = 0.726, p = 0.522, np 2 = 0.195) or across time (F(3,9) = 0.752, p = 0.548, np 2 = 0.200), handgrip strength between conditions (F(2,6) = 0.542, p = 0.607, np 2 = .153) or across time (F(3,9) = 2.235, p = .153, np 2 = .427), or bicep curl strength between conditions (F(2,6) = 0.675, p = 0.554, np 2 = .184) or across time (F(3,9) = 3.513, p = .150, np 2 = .539). There were no differences in pain between conditions (F(2,6) = 0.495, p = 0.633, np 2 = .142), but there was a difference across time (F(3,9) = 7.028, p = .010, np 2 = .701). There were no significant interactions to note. Although there was no statistical significance between conditions (likely due to the low sample size), there was a visible increase in IL-6 48 (4.88 ± 6.53) and 72 hours (3.12 ± 4.26) post exercise in the placebo condition which was not observed in the low (48: 0.35 ± 2.22; 72: 1.34 ± 5.6) and high dose condition (48: 1.34 ± 1.34; 72: -0.79 ± 5.34). Future investigations should consider implementing eccentric resistance training across a larger portion of the body to improve ecological validity of the exercise. A larger sample would reduce risk of researchers committing a type II statistical error and give strength to detecting differences between conditions.
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Objectives: Vaginal bleeding is a common symptom of uterine intracavitary pathologies in perimenopausal and postmenopausal women, which leads to anemia. However, findings regarding the relationship between hemoglobin level and sonographic parameters remain limited. The aim of this study was (1) to investigate the histopathological findings of uterine intracavitary pathologies, hemoglobin concentrations and basic sonographic parameters, and (2) to evaluate their correlation among Vietnamese women with perimenopausal and postmenopausal bleeding. Methods: This was a prospective study at Hue University Hospital and Hue Central Hospital from June 2016 to June 2019. The study enrolled 150 women older than 40 years with abnormal uterine bleeding. All patients underwent blood count testing and transvaginal ultrasound. Results: Moderate to severe anemia was observed at a higher frequency in women with perimenopausal bleeding (58.1%) than postmenopausal bleeding (10.0%). The most common abnormality resulting in severe anemia was endometrial hyperplasia (70.8%), which was followed by endometrial cancer (4.2%). The uterine size, intrauterine mass, and endometrial thickness differed substantially between the benign and malignant groups. The study found significantly a weak negative correlation between hemoglobin concentration (g/L) and uterinelength, the anteroposterior diameter of uterine corpus in the overall study (r = -0.37, r = -0.32, respectively, P < 0.05); a moderate negativecorrelation between hemoglobin concentration and the largest diameter of intracavitary massshaped lesion in the perimenopausal group (r = -0.4, P < 0.05). Conclusion: Overall, histopathological results, hemoglobin concentration and basic sonographic parameters should be combined in evaluating intrauterine abnormalities in women with perimenopausal and postmenopausal bleeding. Ultrasonic indices of uterine size may be used to determine the prognosis of anemia in uterine intracavitary pathologies. However, further studies are needed to confirm these findings.
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OBJECTIVE: Many clinical and imaging characteristics can influence the prognosis of multilevel cervical spondylotic myelopathy (M-CSM). This study investigated the factors that influence surgical outcomes among patients with M-CSM. PATIENTS AND METHODS: This prospective study included 30 patients who underwent surgical treatment for M-CSM from June 2019 to June 2021. RESULTS: The average age was 62.29 years, and the average follow-up time was 13.13 months. Preoperative, postoperative, and follow-up Modified Japanese Orthopaedic Association (mJOA) scores were 10.17, 13.53, and 16.17, respectively. The average postoperative and follow-up recovery rates were 45.46% and 76.69%, respectively. Patients older than 60 years (p = 0.04), male patients (p = 0.023), and smokers (p = 0.027) had lower preoperative mJOA scores than other groups. Patients with symptoms duration longer than 6 months had lower recovery rates (p = 0.021) than those with shorter symptom duration. Patients with intramedullary hyperintensity in ≤ 2 vertebra (p = 0.041) or anterior surgery (p = 0.022) had better postoperative recovery rates than their counterparts. A shorter period of hyperintensity in the intramedullary region on sagittal T2-weighted magnetic resonance imaging (T2W MRI) was significantly associated with faster discharge (p = 0.044). Patients with type 3 (discrete focal) hyperintensity in the intramedullary region on axial T2W MRI had a 6.75-fold increase in experiencing less than 50% postoperative recovery compared with other groups (odds ratio: 6.75, 95% confidence interval: 2.73-16.67). CONCLUSIONS: Good prognostic factors for a shorter recovery included hyperintensity in the intramedullary region for ≤ 2 levels, shorter period of hyperintensity in the intramedullary region on sagittal T2W MRI, and an anterior surgical approach. A duration of symptoms longer than 6 months and discrete hyperintensity in the intramedullary region on axial T2W MRI were poor prognostic indicators associated with a longer recovery period.
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Enfermedades de la Médula Espinal , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/cirugía , Resultado del TratamientoRESUMEN
INTRODUCTION: Contemporary data on the epidemiology of acute myocardial infarction (AMI) in Vietnam are extremely limited. METHODS: We established population-based registries of residents from 2 provinces in a northern urban (Hai Phong), and a central rural (Thanh Hoa), province of Vietnam hospitalized with a validated first AMI in 2018. We described patient characteristics, in-hospital management and clinical complications, and estimated incidence rates of AMI in these two registries. RESULTS: A total of 785 patients (mean age = 71.2 years, 64.7% men) were admitted to the two hospitals with a validated first AMI. Approximately 64% of the AMI cases were ST-segment-elevation AMI. Patients from Thanh Hoa compared with Hai Phong were more likely to delay seeking acute hospital care. The incidence rates (per 100,000 population) of initial AMI in Thanh Hoa and Hai Phong were 16 and 30, respectively. Most patients were treated with aspirin (Thanh Hoa: 96%; Hai Phong: 90%) and statins (both provinces: 91%) during their hospitalization. A greater proportion of patients in Hai Phong (69%) underwent percutaneous revascularization than those in Thanh Hoa (58%). The most common in-hospital complications were heart failure (both provinces:12%), cardiogenic shock (Thanh Hoa: 10%; Hai phong: 7%); and cardiac arrest (both provinces: 9%). The in-hospital case-fatality rates for patients from Thanh Hoa and Hai Phong were 6.8% and 3.8%, respectively. CONCLUSIONS: The incidence and hospital case-fatality rates of AMI were low in two Vietnamese provinces. Extent of pre-hospital delay and in-hospital use of evidence-based therapies were suboptimal, being more prominent in the rural province.
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Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Anciano , Femenino , Mortalidad Hospitalaria , Hospitales , Humanos , Masculino , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/epidemiología , Infarto del Miocardio/terapia , Infarto del Miocardio con Elevación del ST/epidemiología , Choque Cardiogénico/terapia , Vietnam/epidemiologíaRESUMEN
OBJECTIVES: When assessing for lower gastrointestinal bleed (LGIB) using CTA, many advocate for acquiring non-contrast and delayed phases in addition to an arterial phase to improve diagnostic performance though the potential benefit of this approach has not been fully characterized. We evaluate diagnostic accuracy among radiologists when using single-phase, biphasic, and triphasic CTA in active LGIB detection. METHOD AND MATERIALS: A random experimental block design was used where 3 blinded radiologists specialty trained in interventional radiology retrospectively interpreted 96 CTA examinations completed between Oct 2012 and Oct 2017 using (1) arterial only, (2) arterial/non-contrast, and (3) arterial/non-contrast/delayed phase configurations. Confirmed positive and negative LGIB studies were matched, balanced, and randomly ordered. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive and negative predictive values, and time to identify the presence/absence of active bleeding were examined using generalized estimating equations (GEE) with sandwich estimation assuming a binary distribution to estimate relative benefit of diagnostic performance between phase configurations. RESULTS: Specificity increased with additional contrast phases (arterial 72.2; arterial/non-contrast 86.1; arterial/non-contrast/delayed 95.1; p < 0.001) without changes in sensitivity (arterial 77.1; arterial/non-contrast 70.2; arterial/non-contrast/delayed 73.1; p = 0.11) or mean time required to identify bleeding per study (s, arterial 34.8; arterial/non-contrast 33.1; arterial/non-contrast/delayed 36.0; p = 0.99). Overall agreement among readers (Kappa) similarly increased (arterial 0.47; arterial/non-contrast 0.65; arterial/non-contrast/delayed 0.79). CONCLUSION: The addition of non-contrast and delayed phases to arterial phase CTA increased specificity and inter-reader agreement for the detection of lower gastrointestinal bleeding without increasing reading times. KEY POINTS: ⢠A triphasic CTA including non-contrast, arterial, and delayed phase has higher specificity for the detection of lower gastrointestinal bleeding than arterial-phase-only protocols. ⢠Inter-reader agreement increases with additional contrast phases relative to single-phase CTA. ⢠Increasing the number of contrast phases did not increase reading times.
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Angiografía por Tomografía Computarizada , Hemorragia Gastrointestinal , Arterias/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Hemorragia Gastrointestinal/diagnóstico por imagen , Humanos , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
The present environmental crisis prompts the search for renewable energy sources such as solar-driven production of hydrogen from water. Herein, we report an efficient hybrid photocatalyst for water oxidation, consisting of a ruthenium polypyridyl complex covalently grafted on core/shell Fe@FeOx nanoparticles via a phosphonic acid group. The photoelectrochemical measurements were performed under 1 sun illumination in 1 M KOH. The photocurrent density of this hybrid photoanode reached 20 µA/cm2 (applied potential of +1.0 V vs reversible hydrogen electrode), corresponding to a turnover frequency of 0.02 s-1. This performance represents a 9-fold enhancement of that achieved with a mixture of Fe@FeOx nanoparticles and a linker-free ruthenium polypyridyl photosensitizer. This increase in performance could be attributed to a more efficient electron transfer between the ruthenium photosensitizer and the Fe@FeOx catalyst as a consequence of the covalent link between these two species through the phosphonate pendant group.
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Buprenorfina , Infecciones por VIH , Trastornos Relacionados con Opioides , Buprenorfina/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Humanos , Mantenimiento , Metadona , Naloxona , Nitrilos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiología , Derivación y Consulta , VietnamRESUMEN
INTRODUCTION: Prenatal ethanol exposure (PEE) has been shown to alter the level and function of receptors in the brain, one of which is GABAa receptors (GABAaR), the major inhibitory ligand gated ion channels that mediate neuronal inhibition. High dose PEE in animals resulted in the upregulation of GABAaR, but the effects of low and moderate dose PEE at early gestation have not been investigated. This study aimed at examining GABAaR density in the adult mouse brain following PEE during a period equivalent to the first 3 to 4 weeks in human gestation. It was hypothesized that early moderate PEE would cause alterations in brain GABAaR levels in the adult offspring. METHODS: C57BL/6J mice were given 10% v/v ethanol during the first 8 gestational days. Male offspring were studied using in-vivo Positron Emission Tomography (PET)/Magnetic Resonance Imaging (MRI), biodistribution, in-vitro autoradiography using [18F]AH114726, a novel flumazenil analogue with a high affinity for the benzodiazepine-binding site, and validated using immunohistochemistry. RESULTS: In vivo PET and biodistribution did not detect alteration in brain tracer uptake. In vitro radiotracer studies detected significantly reduced GABAaR in the olfactory bulbs. Immunohistochemistry detected reduced GABAaR in the cerebral cortex, cerebellum and hippocampus, while Nissl staining showed that cell density was significantly higher in the striatum following PEE. CONCLUSION: Early moderate PEE may induce long-term alterations in the GABAaR system that persisted into adulthood.
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Benzodiazepinas/química , Encéfalo/metabolismo , Etanol/toxicidad , Flumazenil/metabolismo , Radioisótopos de Flúor/metabolismo , Efectos Tardíos de la Exposición Prenatal/patología , Receptores de GABA-A/metabolismo , Animales , Depresores del Sistema Nervioso Central/toxicidad , Modelos Animales de Enfermedad , Femenino , Flumazenil/química , Masculino , Ratones , Ratones Endogámicos C57BL , Tomografía de Emisión de Positrones/métodos , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/diagnóstico por imagen , Efectos Tardíos de la Exposición Prenatal/metabolismo , Radiofármacos/metabolismo , Distribución TisularRESUMEN
BACKGROUND AND AIM: Chronic hemodialysis patients are at high risk of contracting hepatitis B (HBV) and C (HCV) virus infections. In Vietnam, the seroprevalence of HBV and HCV infections is approximately 10 and 4%, respectively. Although the chronic hemodialysis population is increasing, relatively little epidemiology is available for HBV and HCV infections in this population. To address this, we reviewed the current literature on the magnitude of these infections in the hemodialysis population in Vietnam. METHODS: Four databases were used to search for publications containing the prevalence of HBV and/or HCV infections in hemodialysis patients in Vietnam. Grey literature search was utilized to identify local publications. Prevalence and 95% confidence interval were used or calculated, and a meta-analysis was conducted on HBV and HCV prevalence for comparison. RESULTS: Sixteen studies were included in the review. The search identified knowledge gaps in the current literature. Available data show that HBV and HCV infections remain prevalent in the hemodialysis population. HBV prevalence is not different between the north and the south of Vietnam. The pattern of HCV prevalence is different, with recent reports of lower prevalence in the south than in the north, while HCV prevalence varies between hemodialysis units in the same regions. CONCLUSIONS: A national prevalence survey of hemodialysis patients would improve the reliability and generalizability of the findings. However, the review confirmed that both HBV and HCV were prevalent in hemodialysis patients. The findings support a reinforcement of infection prevention to minimize the risk of HBV and HCV transmission in hemodialysis facilities.
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BACKGROUND: This study investigated the effects of early moderate prenatal ethanol exposure (PEE) on the brain in a mouse model that mimics a scenario in humans, whereby moderate daily drinking ceases after a woman becomes aware of her pregnancy. METHODS: C57BL/6J pregnant mice were given 10% v/v ethanol from gestational day 0-8 in the drinking water. The male offspring were used for imaging. Anatomical and diffusion Magnetic Resonance Imaging were performed in vivo at postnatal day 28 (P28, adolescence) and P80 (adulthood). Micro-Computed Tomography was performed on fixed whole heads at P80. Tensor-based morphometry (TBM) was applied to detect alterations in brain structure and voxel-based morphometry (VBM) for skull morphology. Diffusion tensor and neurite orientation dispersion and density imaging models were used to detect microstructural changes. Neurofilament (NF) immunohistochemistry was used to validate findings by in vivo diffusion MRI. RESULTS: TBM showed that PEE mice exhibited a significantly smaller third ventricle at P28 (family-wise error rate (FWE), p < 0.05). All other macro-structural alterations did not survive FWE corrections but when displayed with an uncorrected p < 0.005 showed multiple regional volume reductions and expansions, more prominently in the right hemisphere. PEE-induced gross volume changes included a bigger thalamus, hypothalamus and ventricles at P28, and bigger total brain volumes at both P28 and P80 (2-sample t-tests). Disproportionately smaller olfactory bulbs following PEE were revealed at both time-points. No alterations in diffusion parameters were detected, but PEE animals exhibited reduced NF positive staining in the thalamus and striatum and greater bone density in various skull regions. CONCLUSION: Our results show that early moderate PEE can cause alterations in the brain that are detectable during development and adulthood.
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Encéfalo/patología , Etanol/efectos adversos , Efectos Tardíos de la Exposición Prenatal/patología , Cráneo/anomalías , Factores de Edad , Animales , Atrofia/patología , Encéfalo/metabolismo , Imagen de Difusión por Resonancia Magnética , Femenino , Procesamiento de Imagen Asistido por Computador , Filamentos Intermedios/metabolismo , Masculino , Ratones , Neuritas/patología , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/metabolismo , Tercer Ventrículo/patología , Microtomografía por Rayos XRESUMEN
The formation of phytoliths as a result of the precipitation of Si in many Si-rich plant species is known to encapsulate organic matter. This work aims to examine the possible encapsulation of Cu in grass phytoliths in an orange growing area, where Cu-rich fungicides have been excessively applied. Batch experiments, in combination with SEM-EDS and microscopy, were conducted for the grass-derived phytoliths and phytoliths separated from soil, thus revealing their dissolution properties, morphotypes and contents, in relation to soil properties. By measuring the Cu release accompanying the dissolution of phytoliths by different extractants, especially an Na2CO3/HNO3 solution, it was revealed that Cu was encapsulated within the silica body of the phytolith. This sink of Cu in the grass can be cycled to serve as a new Cu source in soils. Phytolith contents in the soil were up to 17.7â¯gâ¯kg-1 and tended to accumulate in soil depths from 0 to 20â¯cm. A positive correlation was found for soil phytolith and phytCu contents and may be indicative of the role of phytoliths as an enhancer of Cu accumulation in soil. It would be worth developing suitable techniques for the determination of phytCu, because common extraction/digestion methods are not suited for evaluating this Cu pool.
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Contaminantes del Suelo , Suelo , Cobre , Plantas , Poaceae , SolubilidadRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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The improvement in adsorption/desorption of hydrofluorocarbons has implications for many heat transformation applications such as cooling, refrigeration, heat pumps, power generation, etc. The lack of chlorine in hydrofluorocarbons minimizes the lasting environmental damage to the ozone, with R134a (1,1,1,2-tetrafluoroethane) being used as the primary industrial alternative to commonly used Freon-12. The efficacy of novel adsorbents used in conjunction with R134a requires a deeper understanding of the host-guest chemical interaction. Metal-organic frameworks (MOFs) represent a newer class of adsorbent materials with significant industrial potential given their high surface area, porosity, stability, and tunability. In this work, we studied two benchmark MOFs, a microporous Ni-MOF-74 and mesoporous Cr-MIL-101. We employed a combined experimental and simulation approach to study the adsorption of R134a to better understand host-guest interactions using equilibrium isotherms, enthalpy of adsorption, Henry's coefficients, and radial distribution functions. The overall uptake was shown to be exceptionally high for Cr-MIL-101, >140 wt% near saturation while >50 wt% at very low partial pressures. For both MOFs, simulation data suggest that metal sites provide preferable adsorption sites for fluorocarbon based on favorable C-F ··· M+ interactions between negatively charged fluorine atoms of R134a and positively charged metal atoms of the MOF framework.