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1.
Aging (Albany NY) ; 16(4): 3837-3855, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38376441

RESUMO

Immunotherapy is currently one of the most viable therapies for head and neck squamous cell carcinoma (HNSCC), characterized by high immune cell infiltration. The Wnt-signaling inhibitor and immune activation mediator, Dickkopf-1 (DKK1), has a strong correlation with tumor growth, tumor microenvironment, and, consequently, disease prognosis. Nevertheless, it is still unclear how DKK1 expression, HNSCC prognosis, and tumor-infiltrating lymphocytes are related. To better understand these associations, we examined how DKK1 expression varies across different tumor and normal tissues. In our study, we investigated the association between DKK1 mRNA expression and clinical outcomes. Next, we assessed the link between DKK1 expression and tumor immune cell infiltration. Additionally, using immunohistochemistry, we evaluated the expression of DKK1 in 15 healthy head and neck tissue samples, and the expression of CD3, CD4, and DKK1 in 27 HNSCC samples. We also explored aberrant DKK1 expression during tumorigenesis. DKK1 expression was remarkably higher in HNSCC tissues than in healthy tissues, and was shown to be associated with tumor stage, grade, lymph node metastasis, histology, and a dismal clinical prognosis in HNSCC. DKK1 expression in HNSCC tissues was inversely correlated with CD3+ (P < 0.0001) and CD4+ (P < 0.0001) immune cell infiltration, while that in immune cells was inversely associated with HNSCC prognosis. These findings offer a bioinformatics perspective on the function of DKK1 in HNSCC immunotherapy and provide justification for clinical research on DKK1-targeted HNSCC treatments. DKK1 is a central target for improving the efficacy of HNSCC immunotherapy.


Assuntos
Carcinogênese , Neoplasias de Cabeça e Pescoço , Humanos , Biomarcadores , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microambiente Tumoral
2.
BMJ Open ; 12(4): e053691, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477886

RESUMO

OBJECTIVES: Platelet count is an independent predictor of mortality in patients with cancer. It remains unknown whether the platelet count is related to in-hospital mortality in severely ill patients with tumours. DESIGN: A retrospective study based on a dataset from a multicentre cohort. SETTING: This was a secondary analysis of data from one Electronic Intensive Care Unit Collaborative Research Database survey cycle (2014-2015). PARTICIPANTS: The data pertaining to severely ill patients with tumours were collected from 208 hospitals located across the USA. This study initially a total of 200 859 participants. After the population was limited to patients with combined tumours and platelet deficiencies, the remaining 2628 people were included in the final data analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: The main measure was the platelet count, and the main outcome was in-hospital mortality. RESULTS: After adjustment for the covariates, the platelet count had a curvilinear relationship with in-hospital mortality (p<0.001). The first inflection point was 18.4 (per 10 change). On the left side of the first inflection point (platelet count ≤184 'x10ˆ9/L), an increase of 10 in the platelet count was negatively associated with in-hospital mortality (OR 0.92, 95% CI 0.89 to 0.95, p<0.001). The second inflection point was 44.5 (per 10 change). Additional increases of 10 in the platelet count thereafter were positively associated with hospital mortality (OR 1.13, 95% CI 1.00 to 1.28, p=0.0454). The baseline platelet count was in the range of 184 'x10ˆ9/L-445 'x10ˆ9/L(p=0.0525), and the hospital mortality was lower than the baseline platelet count in other ranges. CONCLUSIONS: The relationship between platelet count and in-hospital mortality in critically ill patients with tumours was curvilinear. The lowest in-hospital mortality was associated with platelet count between 184 'x10ˆ9/Land 445 'x10ˆ9/L. This indicates that both high and low platelet count should receive attention in clinical practice.


Assuntos
Plaquetas , Neoplasias , Estudos de Coortes , Estado Terminal , Mortalidade Hospitalar , Humanos , Estudos Retrospectivos
3.
Eur J Hum Genet ; 30(1): 22-33, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34135477

RESUMO

Hearing impairment (HI) is a common disorder of sensorineural function with a highly heterogeneous genetic background. Although substantial progress has been made in the understanding of the genetic etiology of hereditary HI, many genes implicated in HI remain undiscovered. Via exome and Sanger sequencing of DNA samples obtained from consanguineous Pakistani families that segregate profound prelingual sensorineural HI, we identified rare homozygous missense variants in four genes (ADAMTS1, MPDZ, MVD, and SEZ6) that are likely the underlying cause of HI. Linkage analysis provided statistical evidence that these variants are associated with autosomal recessive nonsyndromic HI. In silico analysis of the mutant proteins encoded by these genes predicted structural, conformational or interaction changes. RNAseq data analysis revealed expression of these genes in the sensory epithelium of the mouse inner ear during embryonic, postnatal, and adult stages. Immunohistochemistry of the mouse cochlear tissue, further confirmed the expression of ADAMTS1, SEZ6, and MPDZ in the neurosensory hair cells of the organ of Corti, while MVD expression was more prominent in the spiral ganglion cells. Overall, supported by in silico mutant protein analysis, animal models, linkage analysis, and spatiotemporal expression profiling in the mouse inner ear, we propose four new candidate genes for HI and expand our understanding of the etiology of HI.


Assuntos
Proteína ADAMTS1/genética , Carboxiliases/genética , Perda Auditiva Neurossensorial/genética , Proteínas de Membrana/genética , Proteína ADAMTS1/química , Proteína ADAMTS1/metabolismo , Animais , Carboxiliases/química , Carboxiliases/metabolismo , Feminino , Genes Recessivos , Células Ciliadas Auditivas/metabolismo , Perda Auditiva Neurossensorial/patologia , Humanos , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Camundongos , Mutação , Linhagem , Domínios Proteicos
4.
Front Cell Dev Biol ; 9: 709442, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34917607

RESUMO

To enable hearing, the sensory hair cell contains specialized subcellular structures at its apical region, including the actin-rich cuticular plate and circumferential band. ACF7 (actin crosslinking family protein 7), encoded by the gene Macf1 (microtubule and actin crosslinking factor 1), is a large cytoskeletal crosslinking protein that interacts with microtubules and filamentous actin to shape cells. ACF7 localizes to the cuticular plate and the circumferential band in the hair cells of vertebrates. The compelling expression pattern of ACF7 in hair cells, combined with conserved roles of this protein in the cytoskeleton of various cell types in invertebrates and vertebrates, led to the hypothesis that ACF7 performs a key function in the subcellular architecture of hair cells. To test the hypothesis, we conditionally target Macf1 in the inner ears of mice. Surprisingly, our data show that in young, but mature, conditional knockout mice cochlear hair cell survival, planar cell polarity, organization of the hair cells within the organ of Corti, and capacity to hear are not significantly impacted. Overall, these results fail to support the hypothesis that ACF7 is an essential hair cell protein in young mice, and the purpose of ACF7 expression in the hair cell remains to be understood.

5.
Hum Mol Genet ; 29(12): 2004-2021, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32167554

RESUMO

Perception of sound is initiated by mechanically gated ion channels at the tips of stereocilia. Mature mammalian auditory hair cells require transmembrane channel-like 1 (TMC1) for mechanotransduction, and mutations of the cognate genetic sequences result in dominant or recessive heritable deafness forms in humans and mice. In contrast, zebrafish lateral line hair cells, which detect water motion, require Tmc2a and Tmc2b. Here, we use standard and multiplex genome editing in conjunction with functional and behavioral assays to determine the reliance of zebrafish hearing and vestibular organs on Tmc proteins. Surprisingly, our approach using multiple mutant alleles demonstrates that hearing in zebrafish is not dependent on Tmc1, nor is it fully dependent on Tmc2a and Tmc2b. Hearing however is absent in triple-mutant zebrafish that lack Tmc1, Tmc2a and Tmc2b. These outcomes reveal a striking resemblance of Tmc protein reliance in the vestibular sensory epithelia of mammals to the maculae of zebrafish. Moreover, our findings disclose a logic of Tmc use where hearing depends on a complement of Tmc proteins beyond those employed to sense water motion.


Assuntos
Perda Auditiva Neurossensorial/genética , Audição/genética , Proteínas de Membrana/genética , Proteínas de Peixe-Zebra/genética , Animais , Surdez/genética , Surdez/patologia , Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/patologia , Células Ciliadas Auditivas Internas/metabolismo , Células Ciliadas Auditivas Internas/patologia , Perda Auditiva Neurossensorial/patologia , Humanos , Mecanotransdução Celular/genética , Camundongos , Mutação/genética , Estereocílios/genética , Estereocílios/patologia , Peixe-Zebra/genética
6.
Front Cell Dev Biol ; 8: 570486, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33490059

RESUMO

Hair cells are heterogenous, enabling varied roles in sensory systems. An emerging hypothesis is that the transmembrane channel-like (Tmc) proteins of the hair cell's mechanotransduction apparatus vary within and between organs to permit encoding of different mechanical stimuli. Five anatomical variables that may coincide with different Tmc use by a hair cell within the ear are the containing organ, cell morphology, cell position within an organ, axis of best sensitivity for the cell, and the hair bundle's orientation within this axis. Here, we test this hypothesis in the organs of the zebrafish ear using a suite of genetic mutations. Transgenesis and quantitative measurements demonstrate two morphologically distinct hair cell types in the central thickness of a vestibular organ, the lateral crista: short and tall. In contrast to what has been observed, we find that tall hair cells that lack Tmc1 generally have substantial reductions in mechanosensitivity. In short hair cells that lack Tmc2 isoforms, mechanotransduction is largely abated. However, hair cell Tmc dependencies are not absolute, and an exceptional class of short hair cell that depends on Tmc1 is present, termed a short hair cell erratic. To further test anatomical variables that may influence Tmc use, we map Tmc1 function in the saccule of mutant larvae that depend just on this Tmc protein to hear. We demonstrate that hair cells that use Tmc1 are found in the posterior region of the saccule, within a single axis of best sensitivity, and hair bundles with opposite orientations retain function. Overall, we determine that Tmc reliance in the ear is dependent on the organ, subtype of hair cell, position within the ear, and axis of best sensitivity.

7.
Nat Commun ; 8(1): 2234, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29269857

RESUMO

Detection of water motion by the lateral line relies on mechanotransduction complexes at stereocilia tips. This sensory system is comprised of neuromasts, patches of hair cells with stereociliary bundles arranged with morphological mirror symmetry that are mechanically responsive to two opposing directions. Here, we find that transmembrane channel-like 2b (Tmc2b) is differentially required for mechanotransduction in the zebrafish lateral line. Despite similarities in neuromast hair cell morphology, three classes of these cells can be distinguished by their Tmc2b reliance. We map mechanosensitivity along the lateral line using imaging and electrophysiology to determine that a hair cell's Tmc2b dependence is governed by neuromast topological position and hair bundle orientation. Overall, water flow is detected by molecular machinery that can vary between hair cells of different neuromasts. Moreover, hair cells within the same neuromast can break morphologic symmetry of the sensory organ at the stereocilia tips.


Assuntos
Sistema da Linha Lateral/metabolismo , Mecanorreceptores/metabolismo , Mecanotransdução Celular/genética , Proteínas de Membrana/metabolismo , Movimento (Física) , Água , Proteínas de Peixe-Zebra/metabolismo , Animais , Sistema da Linha Lateral/fisiologia , Mecanorreceptores/fisiologia , Mecanotransdução Celular/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/fisiologia
8.
Appl Microbiol Biotechnol ; 98(3): 1407-16, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23812277

RESUMO

Alcaligenes faecalis strain JBW4, a strain of bacteria that is capable of degrading endosulfan, was inoculated into sterilized and natural soils spiked with endosulfan. JBW4 degraded 75.8 and 87.0 % of α-endosulfan and 58.5 and 69.5 % of ß-endosulfan in sterilized and natural soils, respectively, after 77 days. Endosulfan ether and endosulfan lactone were the major metabolites that were detected by gas chromatography-mass spectrometry. This result suggested that A. faecalis strain JBW4 degrades endosulfan using a non-oxidative pathway in soils. The ability of strain JBW4 to colonize endosulfan-contaminated soils was confirmed by polymerase chain reaction-denaturing gradient gel electrophoresis. This result suggested that strain JBW4 competed with the original inhabitants in the soil to establish a balance and successfully colonize the soils. In addition, the detoxification of endosulfan by strain JBW4 was evaluated using single-cell gel electrophoresis and by determining the soil microbial biomass carbon and enzymatic activities. The results showed that the genotoxicity and ecotoxicity of endosulfan in soil were reduced after degradation. The natural degradation of endosulfan in soil is inadequate; therefore, JBW4 shows potential for the bioremediation of industrial soils that are contaminated with endosulfan residues.


Assuntos
Alcaligenes faecalis/crescimento & desenvolvimento , Alcaligenes faecalis/metabolismo , Endossulfano/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Biotransformação , Eletroforese em Gel de Gradiente Desnaturante , Cromatografia Gasosa-Espectrometria de Massas , Redes e Vias Metabólicas , Reação em Cadeia da Polimerase , RNA Bacteriano/genética
9.
Ecotoxicol Environ Saf ; 92: 1-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23523001

RESUMO

Endosulfan, an organochlorine pesticide, has been used worldwide in the past decades. The present study was performed to investigate the effect of endosulfan on liver microsomal cytochrome P450 (CYP) enzymes and glutathione S-transferases (GST) in zebrafish. Male and female zebrafish were separated and exposed to a control and four concentrations of endosulfan (0.01, 0.1, 1, and 10µgL(-1)) and were sampled on days 7, 14, 21, and 28. After exposure to endosulfan, the content of CYP increased and later gradually fell back to control level in most sampling time intervals. A similar tendency was also found in the activities of NADPH-P450 reductase (NCR), aminopyrine N-demethylase (APND) and erythromycin N-demethylase (ERND). GST activities were generally higher in treatment groups than control groups. Regarding sex-based differences, the induction degree of the activity of NCR was generally higher in males than females. Similar differences were also found on the 28th day in the activities of APND and ERND, as well as GST activity on the 7th day. Overall, the present results demonstrate the toxicity at low doses of endosulfan and indicated marked induction of CYP and GST enzymes in zebrafish liver.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Endossulfano/toxicidade , Glutationa Transferase/metabolismo , Inseticidas/toxicidade , Aminopirina N-Desmetilase/metabolismo , Animais , Citocromo P-450 CYP3A/metabolismo , Feminino , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Fatores Sexuais , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
10.
Chemosphere ; 91(8): 1107-12, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23399308

RESUMO

Ionic liquids were recently found to be toxic to aquatic organisms. Therefore, the present study investigated the effects of 1-decyl-3-methylimidazolium bromide ([C10mim]Br) on oxidative stress and DNA damage in zebrafish. Male and female zebrafish were separated and exposed to five concentrations of [C10mim]Br (0, 5, 10, 20, and 40 mg L(-1)) and were sampled on days 7, 14, 21 and 28. Compared to control groups, the activities of antioxidant enzymes were significantly decreased at most exposure intervals. This decreased activity resulted in the production of excess reactive oxygen species (ROS) and increased malondialdehyde (MDA) content in zebrafish liver. Additionally, it was noteworthy that a clear dose-response was found for DNA damage. As for sex differences, significant differences in catalase (CAT) and ROS were found on the 7th day. In conclusion, the exposure of [C10mim]Br caused DNA damage, leading to antioxidant responses in zebrafish livers.


Assuntos
Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Fígado/enzimologia , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Dano ao DNA , Feminino , Fígado/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Peixe-Zebra
11.
J Environ Sci (China) ; 25(11): 2257-64, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24552054

RESUMO

The recently discovered endosulfan-degrading bacterial strain Alcaligenesfaecalis JBW4 was isolated from activated sludge. This strain is able to use endosulfan as a carbon and energy source. The optimal conditions for the growth of strain JBW4 and for biodegradation by this strain were identified, and the metabolic products of endosulfan degradation were studied in detail. The maximum level of endosulfan biodegradation by strain JBW4 was obtained using broth at an initial pH of 7.0, an incubation temperature of 40 degreeC and an endosulfan concentration of 100 mg/L. The concentration of endosulfan was determined by gas chromatography. Strain JBW4 was able to degrade 87.5% of alpha-endosulfan and 83.9% of beta-endosulfan within 5 days. These degradation rates are much higher than the previously reported bacterial strains. Endosulfan diol and endosulfan lactone were the major metabolites detected by gas chromatography-mass spectrometry; endosulfan sulfate, which is a persistent and toxic metabolite, was not detected. These results suggested that A. faecalis JBW4 degrades endosulfan via a non-oxidative pathway. The biodegradation of endosulfan by A. faecalis is reported for the first time. Additionally, the present study indicates that strain JBW4 may have potential for the biodegradation of endosulfan residues.


Assuntos
Alcaligenes faecalis/metabolismo , Biodegradação Ambiental , Endossulfano/metabolismo , Inseticidas/metabolismo , Alcaligenes faecalis/genética , Endossulfano/química , Inseticidas/química , Filogenia , Temperatura
12.
Aquat Toxicol ; 124-125: 91-3, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22926335

RESUMO

The present study examined the toxic effects of the exposure to different concentrations of the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate for a 28-day period in zebrafish (Danio rerio) (sampled at 7, 14, 21 and 28 d). The activities of antioxidant enzymes (superoxide dismutase and catalase), levels of reactive oxygen species and DNA damage in fish livers served as the indicators to assess the toxicity of [Omim]PF(6) to zebrafish. The ionic liquid inhibited the activities of the antioxidant enzymes and caused the accumulation of ROS and DNA damage, and the results were concentration- and time-dependent. Male and female fish were tested separately and no differences were observed. The results showed that the ionic liquid could induce oxidative stress and DNA damage in zebrafish and that these effects could also accumulate over time.


Assuntos
Dano ao DNA/efeitos dos fármacos , Imidazóis/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Catalase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Masculino , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo
13.
Ecotoxicology ; 21(5): 1533-40, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22535316

RESUMO

Endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzo-dioxathiepin-3-oxide), an organochlorine pesticide, is prevalently used all around the world. It is considered to be a new candidate for the persistent organic pollutants group. Endosulfan residues in the environment may cause serious damage to ecosystems, especially in aquatic environments. The present study was conducted to investigate the effect of endosulfan on antioxidant enzymes [catalase (CAT) and superoxide dismutase (SOD)], reactive oxygen species (ROS) generation and DNA damage in zebrafish. Male and female zebrafish were separated and exposed to a control solution and four concentrations of endosulfan (0.01, 0.1, 1, and 10 µg L⁻¹) and were sampled after 7, 14, 21, and 28 days. It is noteworthy that the present research explored the correlation among the three indicators induced by endosulfan. Low endosulfan concentrations (0.01 µg L⁻¹) induced a slight increase of SOD and CAT activity, which kept ROS in a stable level. High endosulfan concentration (10 µg L⁻¹) induced excessive ROS production which exceeded the capacity of the cellular antioxidants and exhausted the enzyme including CAT and SOD. The DNA damage of zebrafish was evaluated by single-cell gel electrophoresis and was enhanced with increasing endosulfan concentration. In conclusion, the present study showed that endosulfan (0.01-10 µg L⁻¹) has toxic effects on zebrafish.


Assuntos
Dano ao DNA/efeitos dos fármacos , Endossulfano/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Relação Dose-Resposta a Droga , Ecossistema , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/análise
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