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With the development of artificial intelligence and breakthroughs in deep learning, large-scale foundation models (FMs), such as generative pre-trained transformer (GPT), Sora, etc., have achieved remarkable results in many fields including natural language processing and computer vision. The application of FMs in autonomous driving holds considerable promise. For example, they can contribute to enhancing scene understanding and reasoning. By pre-training on rich linguistic and visual data, FMs can understand and interpret various elements in a driving scene, and provide cognitive reasoning to give linguistic and action instructions for driving decisions and planning. Furthermore, FMs can augment data based on the understanding of driving scenarios to provide feasible scenes of those rare occurrences in the long tail distribution that are unlikely to be encountered during routine driving and data collection. The enhancement can subsequently lead to improvement in the accuracy and reliability of autonomous driving systems. Another testament to the potential of FMs' applications lies in world models, exemplified by the DREAMER series, which showcases the ability to comprehend physical laws and dynamics. Learning from massive data under the paradigm of self-supervised learning, world models can generate unseen yet plausible driving environments, facilitating the enhancement in the prediction of road users' behaviors and the off-line training of driving strategies. In this paper, we synthesize the applications and future trends of FMs in autonomous driving. By utilizing the powerful capabilities of FMs, we strive to tackle the potential issues stemming from the long-tail distribution in autonomous driving, consequently advancing overall safety in this domain.
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BACKGROUND: Protothecosis is an uncommon infection caused by the achlorophyllic algae found more commonly in tropical areas. Only a limited number of cases have been reported. OBJECTIVE: We aimed to evaluate the clinicopathological features and treatment outcomes of cutaneous protothecosis. METHODS: We retrospectively identified 20 pathology-confirmed cases of cutaneous protothecosis based on skin biopsies in two tertiary medical centres in Taiwan from 1997 to 2015. RESULTS: The age of the patients at the time of diagnosis ranged from 48 to 85 years (mean age of 74 years). All lesions developed on the limbs. Twelve (60%) patients had adrenal insufficiency, but no patients had active malignancy at diagnosis. Interestingly, four (20%) patients had concurrent scabies infestation. Clinically, most lesions were erythematous plaques studded with punctate ulcers. Microscopically, the most common finding was granulomatous inflammation. Nineteen (95%) cases were successfully treated with itraconazole for 14-148 days with only one case of recurrence. Concomitant scabies should be suspected if pruritus is recalcitrant despite itraconazole treatment. CONCLUSION: Despite its rarity, cutaneous protothecosis has become more significant due to an increased prevalence of immunocompromised individuals. Steroid overuse or iatrogenic adrenal insufficiency predisposes individuals to high-risk infections. Neglecting the disease leads to a chronic and incurable state. Protothecosis should be suspected in chronic eczematous and ulcerative plaques on the limbs refractory to conventional antibacterial and antiviral treatments, especially in patients with adrenal insufficiency. Clinical suspicion should be confirmed by skin biopsies, and confirmed cases can be successfully treated with itraconazole.
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Prototheca , Escabiosis/complicaciones , Enfermedades Cutáneas Infecciosas/complicaciones , Insuficiencia Suprarrenal/inducido químicamente , Insuficiencia Suprarrenal/complicaciones , Anciano , Anciano de 80 o más Años , Antifúngicos/uso terapéutico , Complicaciones de la Diabetes/complicaciones , Eritema/microbiología , Femenino , Humanos , Itraconazol/uso terapéutico , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/complicaciones , Prurito/parasitología , Estudios Retrospectivos , Factores de Riesgo , Enfermedades Cutáneas Infecciosas/tratamiento farmacológico , Enfermedades Cutáneas Infecciosas/patología , Úlcera Cutánea/microbiologíaRESUMEN
We report a data-set of CO2, CH4, and N2O concentrations in the surface waters of the Meuse river network in Belgium, obtained during four surveys covering 50 stations (summer 2013 and late winter 2013, 2014 and 2015), from yearly cycles in four rivers of variable size and catchment land cover, and from 111 groundwater samples. Surface waters of the Meuse river network were over-saturated in CO2, CH4, N2O with respect to atmospheric equilibrium, acting as sources of these greenhouse gases to the atmosphere, although the dissolved gases also showed marked seasonal and spatial variations. Seasonal variations were related to changes in freshwater discharge following the hydrological cycle, with highest concentrations of CO2, CH4, N2O during low water owing to a longer water residence time and lower currents (i.e. lower gas transfer velocities), both contributing to the accumulation of gases in the water column, combined with higher temperatures favourable to microbial processes. Inter-annual differences of discharge also led to differences in CH4 and N2O that were higher in years with prolonged low water periods. Spatial variations were mostly due to differences in land cover over the catchments, with systems dominated by agriculture (croplands and pastures) having higher CO2, CH4, N2O levels than forested systems. This seemed to be related to higher levels of dissolved and particulate organic matter, as well as dissolved inorganic nitrogen in agriculture dominated systems compared to forested ones. Groundwater had very low CH4 concentrations in the shallow and unconfined aquifers (mostly fractured limestones) of the Meuse basin, hence, should not contribute significantly to the high CH4 levels in surface riverine waters. Owing to high dissolved concentrations, groundwater could potentially transfer important quantities of CO2 and N2O to surface waters of the Meuse basin, although this hypothesis remains to be tested.
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BACKGROUND: Aberrant generation of eicosanoids is associated with asthma, but the evidence remains incomplete and its potential utility as biomarkers is unclear. Major eicosanoids in exhaled breath condensates (EBCs) were assessed as candidate markers for childhood asthma. METHODS: Ten exhaled eicosanoid species was evaluated using ELISA in the discovery phase, followed by prediction model-building and validation phases. RESULTS: Exhaled LTB4 , LTE4 , PGE2, and LXA4 showed significant difference between asthmatics (N = 60) and controls (N = 20). For validation, an expanded study population consisting of 626 subjects with asthma and 161 healthy controls was partitioned into a training subset to establish a prediction model and a test sample subset for validation. Receiver operating characteristic (ROC) analyses of the training subset revealed the level of exhaled LTB4 to be the most discriminative among all parameters, including FeNO, and a composite of exhaled LTB4 , LXA4 , together with FeNO and FEV1 , distinguishing asthma with high sensitivity and specificity. Further, the Youden index (J) indicated the cut point value of 0.598 for this composite of markers as having the strongest discriminatory ability (sensitivity = 85.2% and specificity = 83.6%). The predictive algorithm as "asthma classification ratio" was further validated in an independent test sample with sensitivity and specificity being 84.4% and 84.8%, respectively. CONCLUSIONS: In a pediatric study population in Taiwan, the levels of exhaled LTB4 , LTE4 , LXA4, and PGE2 in asthmatic children were significantly different from those of healthy controls, and the combination of exhaled LTB4 and LXA4 , together with FeNO and FEV1 , best characterized childhood asthma.
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Asma/clasificación , Asma/diagnóstico , Biomarcadores/análisis , Algoritmos , Área Bajo la Curva , Pruebas Respiratorias , Niño , Preescolar , Dinoprostona/análisis , Eicosanoides/análisis , Femenino , Volumen Espiratorio Forzado , Humanos , Leucotrieno B4/análisis , Leucotrieno E4/análisis , Lipoxinas/análisis , Masculino , Óxido Nítrico/análisis , Curva ROC , Sensibilidad y EspecificidadRESUMEN
Background: The optimal volume status for neurosurgery has yet to be determined. We compared two fluid protocols based on different stroke volume variation (SVV) cut-offs for goal-directed fluid therapy (GDFT) during supratentorial brain tumour resection. Methods: A randomized, single-blind, open-label trial was conducted. Eighty adult patients undergoing elective supratentorial brain tumour resection were randomly divided into a low SVV and a high SVV group. The SVV cut-offs were used to determine when to initiate colloid infusion. Clinical outcomes and perioperative changes in serum neuronal biomarkers, including S100ß, neurone-specific enolase (NSE) and glial fibrillary acidic protein (GFAP), were compared. Results: Patients in the low SVV group received a higher volume of colloid [869 (SD 404) vs 569 (453) ml; P=0.0025], had a higher urine output [3.4 (2.4) vs 2.5 (1.7) ml kg-1 h-1; P=0.0416] and a higher average cardiac index [3.2 (0.7) vs 2.8 (0.6) litres min-1 m-2; P=0.0204]. Patients in the low SVV group also had a shorter intensive care unit stay [1.4 (0.7) vs 2.6 (3.3) days, P=0.0326], fewer postoperative neurological events (17.5 vs 40%, P=0.0469), attenuated changes in the NSE and GFAP levels, lower intraoperative serum lactate and a higher Barthel index at discharge (all P<0.05). Conclusions: During GDFT for supratentorial brain tumour resection, fluid boluses targeting a lower SVV are more beneficial than a restrictive protocol. Clinical trial registration: NCT02113358.
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Fluidoterapia/métodos , Cuidados Intraoperatorios/métodos , Volumen Sistólico/fisiología , Neoplasias Supratentoriales/cirugía , Encéfalo/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Método Simple Ciego , Resultado del TratamientoRESUMEN
Tumor cells often produce high levels of reactive oxygen species (ROS) and display an increased ROS scavenging system. However, the molecular mechanism that balances antioxidative and oxidative stress in cancer cells is unclear. Here, we determined that oncogenic multiple copies in T-cell malignancy 1 (MCT-1) activity promotes the generation of intracellular ROS and mitochondrial superoxide. Overexpression of MCT-1 suppresses p53 accumulation but elevates the manganese-dependent superoxide dismutase (MnSOD) level via the YY1-EGFR signaling cascade, which protects cells against oxidative damage. Conversely, restricting ROS generation and/or targeting YY1 in lung cancer cells effectively inhibits the EGFR-MnSOD signaling pathway and cell invasiveness induced by MCT-1. Significantly, MCT-1 overexpression in lung cancer cells promotes tumor progression, necrosis and angiogenesis, and increases the number of tumor-promoting M2 macrophages and cancer-associated fibroblasts in the microenvironment. Clinical evidence further confirms that high expression of MCT-1 is associated with an increase in YY1, EGFR and MnSOD expression, accompanied by tumor recurrence, poor overall survival and EGFR mutation status in patients with lung cancers. Together, these data indicate that the MCT-1 oncogenic pathway is implicated in oxidative metabolism and lung carcinogenesis.
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Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/efectos adversos , Quimioembolización Terapéutica/métodos , Ictericia Obstructiva/etiología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/terapia , Recurrencia Local de Neoplasia/complicaciones , Recurrencia Local de Neoplasia/terapia , Carcinoma Hepatocelular/patología , Colangiopancreatografia Retrógrada Endoscópica , Conducto Colédoco/diagnóstico por imagen , Conducto Colédoco/patología , Humanos , Ictericia Obstructiva/diagnóstico por imagen , Neoplasias Hepáticas/patología , Persona de Mediana Edad , Necrosis , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Current diagnosis and staging of pancreatic ductal adenocarcinoma (PDAC) has important limitations and better biomarkers are needed to guide initial therapy. We investigated the performance of circulating tumour cells (CTCs) as an adjunctive biomarker at the time of disease presentation. METHODS: Venous blood (VB) was collected prospectively from 100 consecutive, pre-treatment patients with PDAC. Utilising the microfluidic NanoVelcro CTC chip, samples were evaluated for the presence and number of CTCs. KRAS mutation analysis was used to compare the CTCs with primary tumour tissue. CTC enumeration data was then evaluated as a diagnostic and staging biomarker in the setting of PDAC. RESULTS: We found 100% concordance for KRAS mutation subtype between primary tumour and CTCs in all five patients tested. Evaluation of CTCs as a diagnostic revealed the presence of CTCs in 54/72 patients with confirmed PDAC (sensitivity=75.0%, specificity=96.4%, area under the curve (AUROC)=0.867, 95% CI=0.798-0.935, and P<0.001). Furthermore, a cut-off of ⩾3 CTCs in 4 ml VB was able to discriminate between local/regional and metastatic disease (AUROC=0.885; 95% CI=0.800-0.969; and P<0.001). CONCLUSION: CTCs appear to function well as a biomarker for diagnosis and staging in PDAC.
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Carcinoma Ductal Pancreático/patología , Células Neoplásicas Circulantes/patología , Neoplasias Pancreáticas/patología , Biomarcadores de Tumor/sangre , Carcinoma Ductal Pancreático/sangre , Estudios de Cohortes , Humanos , Estadificación de Neoplasias , Neoplasias Pancreáticas/sangre , Proteínas Proto-Oncogénicas p21(ras)/genéticaRESUMEN
PURPOSE: The success of stone removal with sialendoscopic lithotripsy in the management of lithiasis-related obstructive sialoadenitis has been reported, but the proper management for patients with non-lithiasis obstructive sialoadenitis remains unclear. This study aims to report experiences in sialendoscopy for the management of obstructive sialoadenitis with and without the presence of stones. METHODS: Data from 71 procedures in 66 patients who underwent sialendoscopy for obstructive sialoadenitis were recorded and compared in terms of clinical data, computed tomography (CT) findings, procedural techniques and outcomes. RESULTS: The overall specificity rate of CT for detecting sialolithiasis was 91.6%. The complete remission rate was 100% for patients with confirmed sialolithiasis successfully treated with stone removal after endoscopic lithotripsy. For patients with non-sialolithiasis obstructive sialoadenitis of the submandibular gland, the complete remission rate dropped to 22% if no additional treatments were done after a diagnostic sialendoscopy. If sialostents were inserted, the complete remission rate increased to 55%. However, this improvement was very limited in terms of the overall management of the affected parotid gland. CONCLUSION: For patients with obstructive sialoadenitis and salivary gland stones, removal of the stones under sialendoscopy will most likely provide complete remission. Patients without stones have much worse treatment outcomes compared to those with true sialolithiasis. Sialostent placement may have the potential to improve treatment outcomes in the management of non-lithiasis obstructive sialoadenitis.
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Endoscopía , Sialadenitis/terapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Litotripsia por Láser , Masculino , Persona de Mediana Edad , Inducción de Remisión , Estudios Retrospectivos , Cálculos de las Glándulas Salivales/complicaciones , Cálculos de las Glándulas Salivales/diagnóstico , Cálculos de las Glándulas Salivales/terapia , Sialadenitis/diagnóstico , Sialadenitis/etiología , Stents , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
Inositol polyphosphate 4-phosphatase type II (INPP4B) negatively regulates phosphatidylinositol 3-kinase signaling and is a tumor suppressor in some types of cancers. However, we have found that it is frequently upregulated in human colon cancer cells. Here we show that silencing of INPP4B blocks activation of Akt and serum- and glucocorticoid-regulated kinase 3 (SGK3), inhibits colon cancer cell proliferation and retards colon cancer xenograft growth. Conversely, overexpression of INPP4B increases proliferation and triggers anchorage-independent growth of normal colon epithelial cells. Moreover, we demonstrate that the effect of INPP4B on Akt and SGK3 is associated with inactivation of phosphate and tensin homolog through its protein phosphatase activity and that the increase in INPP4B is due to Ets-1-mediated transcriptional upregulation in colon cancer cells. Collectively, these results suggest that INPP4B may function as an oncogenic driver in colon cancer, with potential implications for targeting INPP4B as a novel approach to treat this disease.
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Neoplasias del Colon/genética , Monoéster Fosfórico Hidrolasas/genética , Línea Celular Tumoral , Proliferación Celular/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Humanos , Inmunohistoquímica , Monoéster Fosfórico Hidrolasas/metabolismoRESUMEN
Naproxen is an anti-inflammatory drug that affects cellular calcium ion (Ca(2+)) homeostasis and viability in different cells. This study explored the effect of naproxen on [Ca(2+)](i) and viability in Madin-Darby canine kidney cells (MDCK) canine renal tubular cells. At concentrations between 50 µM and 300 µM, naproxen induced [Ca(2+)](i) rises in a concentration-dependent manner. This Ca(2+) signal was reduced partly when extracellular Ca(2+) was removed. The Ca(2+) signal was inhibited by a Ca(2+) channel blocker nifedipine but not by store-operated Ca(2+) channel inhibitors (econazole and SKF96365), a protein kinase C (PKC) activator phorbol 12-myristate 13-acetate, and a PKC inhibitor GF109203X. In Ca(2+)-free medium, pretreatment with 2,5-di-tert-butylhydroquinone or thapsigargin, an inhibitor of endoplasmic reticulum Ca(2+) pumps, partly inhibited naproxen-induced Ca(2+) signal. Inhibition of phospholipase C with U73122 did not alter naproxen-evoked [Ca(2+)](i) rises. At concentrations between 15 µM and 30 µM, naproxen killed cells in a concentration-dependent manner, which was not reversed by prechelating cytosolic Ca(2+) with the acetoxymethyl ester of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl. Annexin V/propidium iodide staining data suggest that naproxen induced apoptosis. Together, in MDCK renal tubular cells, naproxen induced [Ca(2+)](i) rises by inducing Ca(2+) release from multiple stores that included the endoplasmic reticulum and Ca(2+) entry via nifedipine-sensitive Ca(2+) channels. Naproxen induced cell death that involved apoptosis.
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Antiinflamatorios no Esteroideos/farmacología , Calcio/metabolismo , Células de Riñón Canino Madin Darby/efectos de los fármacos , Naproxeno/farmacología , Animales , Bloqueadores de los Canales de Calcio/farmacología , Muerte Celular/efectos de los fármacos , Perros , Imidazoles/farmacología , Indoles/farmacología , Células de Riñón Canino Madin Darby/metabolismo , Maleimidas/farmacología , Nifedipino/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Acetato de Tetradecanoilforbol/farmacologíaRESUMEN
BACKGROUNDS: Diabetes mellitus (DM) is a common endocrine disorder and an increasing epidemic worldwide. Proportional diabetic patients eventually develop cutaneous diseases. OBJECTIVES: This study determined the statistical association of cutaneous manifestations and DM as well as the DM-associated cutaneous manifestations in elderly male residents. METHODS: A cross-sectional study was conducted in a Veterans Home in Taiwan. The cutaneous manifestations and major systemic diseases of the residents were recorded separately. Univariate logistic regression and multivariate analysis after adjustment for age, body mass index and significant major systemic diseases provided odds ratios and P values for the statistical association. RESULTS: A total of 313 male residents (age ≥65 years) were recruited, including 70 (22.4%) with DM. Their most common cutaneous manifestations included fungal infection (77%) and brown spots on the legs (38.3%). Chronic ulcers adjusted odds ratios (AOR 4.90, 95%CI: 1.82-13.19; P = 0.002), brown spots on the legs (AOR 6.82, 95%CI: 3.60-12.89; P < 0.001) and pruritus (AOR 12.86, 95%CI: 4.40-37.59; P < 0.001) were significantly associated with DM. The diabetic residents were inclined to have chronic ulcers, brown spots on the legs and pruritus at a 7.46-fold higher risk (AOR 7.46, 95%CI: 3.86-14.43; P < 0.001). The diabetic residents exhibited marginally higher risks of bacterial infection, scabies, or skin tags. CONCLUSION: The DM-associated cutaneous manifestations were chronic ulcers, brown spots on the legs, and pruritus. By observing clues of diabetic cutaneous features, a more complete condition of diabetic patients can be appreciated. The information is essential for providing appropriate treatment and key nursing points regarding the diabetes-associated skin diseases.
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Complicaciones de la Diabetes/epidemiología , Enfermedades de la Piel/epidemiología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Hogares para Ancianos , Humanos , Masculino , Prevalencia , TaiwánRESUMEN
Purinergic receptors are implicated in nociceptive signaling in small primary afferents via activation of adenosine triphosphate (ATP). ATP appears to mediate HCl-induced transient receptor potential vanilloid receptor 1 (TRPV1) activation in esophageal mucosa. Up-regulation of TRPV1 expression in gastroesophageal reflux disease (GERD) is associated with increased nerve growth factor (NGF) and glial derived neurotrophic factor (GDNF). This study aims to genetically determine the expression of purinergic receptors in severe inflamed human esophagus. Distal esophageal biopsies from the subjects with erosive GERD, asymptomatic patients (AP) and healthy ones were examined. Using real-time qPCR for detecting purinergic receptors (P2X2, P2X3, P2X7, P2Y1, P2Y2, P2Y4, P2Y6 and P2Y12), TRPV1, TRPV4, NGF, and GDNF was done in this study. Both P2X3 and P2X7 mRNA expressions in GERD patients significantly increased than those in healthy controls (P < 0.001) and AP (P < 0.001), but P2X2, P2Y1, P2Y2, P2Y4, P2Y6, P2Y12 or P2Y12 had no difference within the control, AP or GERD subjects. The well correlated expression in P2X3 gene with TRPV1 (r = 0.46, P = 0.002), NGF (r = 0.54, P = 0.0002), and GDNF (r = 0.64, P = 0.0001) was found. The P2X7 gene expressions also well correlated with TRPV1 (r = 0.47, P = 0.002), NGF (r = 0.32, P = 0.037), and GDNF (r = 0.42, P = 0.005). These results suggest that chronic esophagitis increases mRNA expressions of P2X3 and P2X7 receptors accompanied by up-regulation of TRPV1 and neurotrophic factors (NGF and GDNF). These genetical alterations in esophageal mucosa might mediate sensitization of inflamed human esophagus.
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Esofagitis Péptica/metabolismo , Esófago/metabolismo , Receptores Purinérgicos P2X3/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Canales Catiónicos TRPV/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Expresión Génica , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factor de Crecimiento Nervioso/metabolismo , Receptores Purinérgicos P2X3/genética , Receptores Purinérgicos P2X7/genética , Regulación hacia Arriba , Adulto JovenRESUMEN
BACKGROUND: The Venturi-principle atomizer is a commonly used device in otolaryngology practices. The purpose of this study is to evaluate the possible route of bacterial contamination from the nasal vestibule to the atomizer tip through the jet airflow created during the use of the Venturi atomizer. METHODS: Thirty nostrils from 15 enrolled volunteers were tested. The aerosols generated by spraying sterilized saline into the nostrils were collected using a specially made aerosol-collecting nozzle cap. The collected samples were sent for bacterial culture, and nasal vestibular swab cultures were performed for comparison. RESULTS: In the aerosol-exposed group, 18 out of 30 samples (60%) were positive for bacterial growth, confirming the bacterial contamination from the nasal vestibule to the atomizer tip through the reverse jet airflow. The bacteria species in 8 of the 18 positive samples were identical to those from the nasal swab culture results from the same nostril. CONCLUSION: In ordinary otolaryngology practices, there are significant risks for bacterial contamination from the nasal vestibule to the tip of the Venturi atomizer even without direct contact. Clinicians must be more aware of this pattern of contamination, which has not been reported in the existing literature.
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Contaminación de Equipos , Cavidad Nasal/microbiología , Nebulizadores y Vaporizadores/microbiología , Otolaringología/instrumentación , Administración Intranasal/instrumentación , Enterobacteriaceae/aislamiento & purificación , Diseño de Equipo , Humanos , Rociadores Nasales , Staphylococcus/aislamiento & purificaciónRESUMEN
BACKGROUND: Tryptophan metabolites have been suggested to play a role in immune modulation, wherein those have recently been shown to be endogenous ligands of aryl hydrocarbon receptor (AhR; a unique cellular chemical sensor). However, the involvement of tryptophan metabolites and AhR in modulating mast cell function remains to be fully defined. We therefore investigated that the functional impacts of tryptophan metabolites on human and mouse mast cell responses in vitro and their functional importance in vivo. METHODS: Three tryptophan metabolites, kynurenine (KYN), kynurenic acid (KA) and quinolinic acid (QA), were examined in terms of their effect on IgE-mediated responses in mouse bone marrow-derived mast cells (BMMCs) and in human peripheral blood-derived cultured mast cells (HCMCs) and on in vivo anaphylactic responses. For evaluation of AhR involvement, we examined the responses of mast cells from AhR-null or AhR-wild-type mice with the use of a known AhR antagonist, CH223191. RESULTS: Kynurenine, but not KA and QA, enhanced IgE-mediated responses, including degranulation, LTC4 release, and IL-13 production in BMMCs through the activation of PLCγ1, Akt, MAPK p38, and the increase of intracellular calcium. KYN also enhanced cutaneous anaphylaxis in vivo. These enhancing effects of KYN were not observed in AhR-deficient BMMCs and could be inhibited by CH223191 in BMMCs. Further, KYN had similar enhancing effects on HCMCs, which were inhibited by CH223191. CONCLUSION: The AhR-KYN axis is potentially important in modulating mast cell responses and represents an example of AhR's critical involvement in the regulation of allergic responses.
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Quinurenina/farmacología , Mastocitos/inmunología , Mastocitos/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Triptófano/metabolismo , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/metabolismo , Células Cultivadas , Humanos , Inmunoglobulina E/inmunología , Quinurenina/administración & dosificación , Mastocitos/efectos de los fármacos , Ratones , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Singapore is a small industrialized island state with a low accident rate and few hazardous chemical-related injuries reported. However, the use of chemicals continues to increase and pose hazards in the workplace. AIMS: To study workplace chemical injuries and exposures to improve worksite safety. METHODS: Work-related chemical exposure cases were identified from emergency department (ED) computerized records from 2007 to 2010. RESULTS: A total of 239 cases were identified. Most of the patients were male (92%) and young adults (73% aged between 21 and 40 years). Fifty per cent of the workers were foreign workers. Most of them were cleaners, labourers and technicians (53%) and worked mainly in the construction and manufacturing industries (47%). All the exposures were acute and presented within 4h of the exposure incident (52%). Most of the chemical exposures were to the eye (55%) and skin (32%). The chemicals involved included corrosives (41%), hydrocarbons (18%) and cleaning solutions (9%). Pre-hospital decontamination (eye and skin irrigation) was performed for 54% of the workers. Antidote treatment with calcium gluconate for hydrofluoric acid exposure was used for five patients in the ED. Only 11% of patients were admitted. Four patients had surgical procedures and five patients had long-term complications. Forty-five incidents were notified to the Ministry of Manpower. The under-reporting rate for cases with >3 days of medical leave was 66%. CONCLUSIONS: Work-related chemical exposures that present to the ED had low morbidity. Most of the workers did well with immediate decontamination and supportive treatment but antidotes were required for some exposures.
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Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Intoxicación/epidemiología , Adolescente , Adulto , Anciano , Servicios Médicos de Urgencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Singapur/epidemiologíaRESUMEN
Increased global protein synthesis and selective translation of mRNAs encoding proteins contributing to malignancy is common in cancer cells. This is often associated with elevated expression of eukaryotic translation initiation factor 4 (eIF4E), the rate-limiting factor of cap-dependent translation initiation. We report here that in human melanoma downregulation of miR-768-3p as a result of activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway has an important role in the upregulation of eIF4E and enhancement in protein synthesis. Melanoma cells displayed increased nascent protein production and elevated eIF4E expression, which was associated with the downregulation of miR-768-3p that was predicted to target the 3'-untranslated region of the eIF4E mRNA. Overexpression of miR-768-3p led to the downregulation of the endogenous eIF4E protein, reduction in nascent protein synthesis and inhibition of cell survival and proliferation. These effects were efficiently reversed when eIF4E was co-overexpressed in melanoma cells. On the other hand, introduction of anti-miR-768-3p into melanocytes upregulated endogenous eIF4E protein expression and increased global protein synthesis. Downregulation of miR-768-3p appeared to be mediated by activation of the MEK/ERK pathway, in that treatment of BRAF(V600E) melanoma cells with the mutant BRAF inhibitor PLX4720 or exposure of either BRAF(V600E) or wild-type BRAF melanoma cells to the MEK inhibitor U0126 resulted in the upregulation of miR-768-3p and inhibition of nascent protein synthesis. This inhibition was partially blocked in cells cointroduced with anti-miR-768-3p. Significantly, miR-768-3p was similarly downregulated, which was inversely associated with the expression levels of eIF4E in fresh melanoma isolates. Taken together, these results identify downregulation of miR-768-3p and subsequent upregulation of eIF4E as an important mechanism in addition to phosphorylation of eIF4E responsible for MEK/ERK-mediated enhancement of protein synthesis in melanoma.