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1.
Cancer Radiother ; 26(8): 1002-1007, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35933288

RESUMO

PURPOSE: Chemoradiotherapy is regarded as a standard scheme for inoperable and unresectable esophageal cancers. Our aims were to explore the prognostic factors relevant to esophageal squamous cell carcinoma (ESCC) following intensity-modulated radiation therapy (IMRT) plus chemotherapy. MATERIAL AND METHODS: Totally 495 ESCC patients undergoing IMRT combined with chemotherapy in our hospital between 2011 and 2020 were retrospectively analyzed. Potential clinical prognosis-related factors were assessed by uni- and multivariate analyses. RESULTS: The median overall survival (OS) and progression-free survival (PFS) of the ESCC patients were 2.25 and 1.24years, respectively. Uni- and multivariate analyses demonstrated the relevant independent prognostic factors of OS and PFS were gender, T stage, N stage, clinical stage, and tumor location (P<0.05), but not chemotherapy or radiotherapy dose. We further compared the 5-year OS rates among different T stages, N stages, clinical stages, genders, and tumor locations. The survival rate at the higher clinical stage was significantly lower (P<0.001). The 5-year OS in the upper thorax of the tumor was 46.0% and exceeded other tumor locations (P<0.05). The 5-year OS was 56.1% among females and 33.3% among males (P=0.001). CONCLUSIONS: For ESCC patients receiving IMRT combined with chemotherapy, their long-term curative effects are influenced by T stages, N stages, clinical stages, genders, and tumor locations. ESCC patients who are females, or have upper thoracic tumor, or are at early clinical stage own better prognosis.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Radioterapia de Intensidade Modulada , Humanos , Feminino , Masculino , Carcinoma de Células Escamosas do Esôfago/terapia , Neoplasias Esofágicas/patologia , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos , Prognóstico , Quimiorradioterapia/efeitos adversos
4.
Leukemia ; 32(5): 1147-1156, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29434279

RESUMO

Aberrant activation of the JAK3-STAT signaling pathway is a characteristic feature of many hematological malignancies. In particular, hyperactivity of this cascade has been observed in natural killer/T-cell lymphoma (NKTL) cases. Although the first-in-class JAK3 inhibitor tofacitinib blocks JAK3 activity in NKTL both in vitro and in vivo, its clinical utilization in cancer therapy has been limited by the pan-JAK inhibition activity. To improve the therapeutic efficacy of JAK3 inhibition in NKTL, we have developed a highly selective and durable JAK3 inhibitor PRN371 that potently inhibits JAK3 activity over the other JAK family members JAK1, JAK2, and TYK2. PRN371 effectively suppresses NKTL cell proliferation and induces apoptosis through abrogation of the JAK3-STAT signaling. Moreover, the activity of PRN371 has a more durable inhibition on JAK3 compared to tofacitinib in vitro, leading to significant tumor growth inhibition in a NKTL xenograft model harboring JAK3 activating mutation. These findings provide a novel therapeutic approach for the treatment of NKTL.


Assuntos
Janus Quinase 3/antagonistas & inibidores , Linfoma de Células T/tratamento farmacológico , Piridonas/uso terapêutico , Pirimidinas/uso terapêutico , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Xenoenxertos/efeitos dos fármacos , Humanos , Janus Quinase 3/metabolismo , Camundongos , Células T Matadoras Naturais/patologia , Piridonas/farmacologia , Pirimidinas/farmacologia
5.
Pol J Vet Sci ; 20(2): 277-284, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28865219

RESUMO

Streptococcus suis serotype 2 (SS2) is considered as a major pathogen that causes sepsis and meningitis in piglets and humans, but knowledge of its antigenic proteins remains limited so far. The surface-related proteins of pathogens often play significant roles in bacterium-host interactions and infection. Here, we obtained the elongation factor Tu (EF-Tu) gene of Streptococcus suis and constructed the recombinant expression plasmid successfully. The target recombinant plasmid was then expressed in Escherichia coli and the immuno-protection of the recombinant protein was subsequently evaluated as well. The EF-Tu gene of Streptococcus suis is 1197 bp in length, encodes 398 amino acids. The target recombinant EF-Tu (rEF-Tu) protein can recognize the antiserum of Streptococcus suis and can provoke obvious humoral immune responses in rabbits and conferred protection to rabbits against Streptococcus suis ear-vein challenge, implying that the EF-Tu may be used as an attractive candidate antigen for a component of subunit vaccine.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Fator Tu de Elongação de Peptídeos/metabolismo , Streptococcus suis/metabolismo , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Vacinas Bacterianas/imunologia , Clonagem Molecular , Fator Tu de Elongação de Peptídeos/genética , Coelhos , Sorogrupo , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/prevenção & controle , Streptococcus suis/genética , Streptococcus suis/imunologia
6.
Cell Death Discov ; 2: 15065, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551491

RESUMO

Autophagy has been linked to the regulation of both the prevention and progression of cancer. IFN-γ has been shown to induce autophagy in multiple cell lines in vitro. However, whether IFN-γ can induce autophagy and whether autophagy promotes malignant transformation in healthy lactating bovine mammary epithelial cells (BMECs) remain unclear. Here, we provide the first evidence of the correlation between IFN-γ treatment, autophagy and malignant transformation and of the mechanism underlying IFN-γ-induced autophagy and subsequent malignant transformation in primary BMECs. IFN-γ levels were significantly increased in cattle that received normal long-term dietary corn straw (CS) roughage supplementation. In addition, an increase in autophagy was clearly observed in the BMECs from the mammary tissue of cows expressing high levels of IFN-γ. In vitro, autophagy was clearly induced in primary BMECs by IFN-γ within 24 h. This induced autophagy could subsequently promote dramatic primary BMEC transformation. Furthermore, we found that IFN-γ promoted arginine depletion, activated the general control nonderepressible-2 kinase (GCN2) signalling pathway and resulted in an increase in autophagic flux and the amount of autophagy in BMECs. Overall, our findings are the first to demonstrate that arginine depletion and kinase GCN2 expression mediate IFN-γ-induced autophagy that may promote malignant progression and that immunometabolism, autophagy and cancer are strongly correlated. These results suggest new directions and paths for preventing and treating breast cancer in relation to diet.

8.
Genet Mol Res ; 15(1)2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26909954

RESUMO

Plasma membrane proteolipid 3 (PMP3) is a class of small hydrophobic proteins found in many organisms including higher plants. Some plant PMP3 genes have been shown to respond to abiotic stresses and to participate in the processes of plant stress tolerance. In this study, we isolated the cassava (Manihot esculenta Crantz) MePMP3-2 gene and functionally characterized its role in tolerance to abiotic stress by expressing it in rice (Oryza sativa L.). MePMP3-2 encodes a 77-amino acid protein belonging to a subgroup of plant PMP3s that have long hydrophylic C-terminal tails of unknown function. In silico analysis and co-localization studies indicated that MePMP3-2 is a plasma membrane protein with two transmembrane domains, similar to other PMP3s. In cassava leaves, MePMP3-2 expression was up-regulated by salt and drought stresses. Heterologous constitutive expression of MePMP3-2 in rice did not alter plant growth and development but increased tolerance to salt and drought stresses. In addition, under stress conditions MePMP3-2 transgenic plants accumulated less malondialdehyde, had increased levels of proline, and exhibited greater up-regulation of the stress-related genes OsProT and OsP5CS, but led to only minor changes in OsDREB2A and OsLEA3 expression. These findings indicate that MePMP3-2 may play an important role in salt and drought stress tolerance in transgenic rice.


Assuntos
Adaptação Fisiológica , Regulação da Expressão Gênica de Plantas , Manihot/fisiologia , Proteínas de Membrana/fisiologia , Oryza/fisiologia , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Sequência de Aminoácidos , Simulação por Computador , Secas , Manihot/genética , Manihot/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Oryza/genética , Oryza/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteolipídeos/fisiologia , Tolerância ao Sal , Alinhamento de Sequência , Regulação para Cima
9.
Clin Exp Dermatol ; 40(8): 875-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25810249

RESUMO

We describe a case of primary cutaneous mucormycosis in a 44-year-old man with an 18-month history of infiltrative erythematous plaques and haemorrhagic crusting on the dorsum of his left hand. The isolate was identified as Mucor irregularis (formerly Rhizomucor variabilis) based on the fungus morphology and DNA sequencing results. Improvement was observed after a 6-month treatment course of itraconazole. No recrudescence was seen during a follow-up of 23 months after treatment.


Assuntos
Dermatomicoses/microbiologia , Dermatoses da Mão/microbiologia , Mucormicose/microbiologia , Rhizomucor/isolamento & purificação , Adulto , Antifúngicos/uso terapêutico , Dermatomicoses/tratamento farmacológico , Dermatoses da Mão/tratamento farmacológico , Humanos , Itraconazol/uso terapêutico , Masculino , Mucormicose/tratamento farmacológico , Resultado do Tratamento
10.
Plant Biol (Stuttg) ; 17(1): 81-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24985337

RESUMO

Plant responses to elevated CO2 and high temperature are critically regulated through a complex network of phytohormones and redox homeostasis. However, the involvement of abscisic acid (ABA) in plant adaptation to heat stress under elevated CO2 conditions has not been thoroughly studied. This study investigated the interactive effects of elevated CO2 (800 µmol·mol(-1) ) and heat stress (42 °C for 24 h) on the endogenous level of ABA and the cellular redox state of two genotypes of tomato with different ABA biosynthesis capacities. Heat stress significantly decreased maximum photochemical efficiency of PSII (Fv/Fm) and leaf water potential, but also increased levels of malondialdehyde (MDA) and electrolyte leakage (EL) in both genotypes. Heat-induced damage was more severe in the ABA-deficient mutant notabilis (not) than in its parental cultivar Ailsa Craig (Ailsa), suggesting that a certain level of endogenous ABA is required to minimise the heat-induced oxidative damage to the photosynthetic apparatus. Irrespective of genotype, the enrichment of CO2 remarkably stimulated Fv/Fm, MDA and EL in heat-stressed plants towards enhanced tolerance. In addition, elevated CO2 significantly strengthened the antioxidant capacity of heat-stressed tomato seedlings towards a reduced cellular redox state for a prolonged period, thereby mitigating oxidative stress. However, elevated CO2 and heat stress did not alter the endogenous level of ABA or the expression of its biosynthetic gene NCED2 in either genotype, indicating that ABA is not involved in elevated CO2 -induced heat stress alleviation. The results of this study suggest that elevated CO2 alleviated heat stress through efficient regulation of the cellular redox poise in an ABA-independent manner in tomato plants.


Assuntos
Adaptação Fisiológica , Dióxido de Carbono/metabolismo , Solanum lycopersicum/fisiologia , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Genótipo , Homeostase , Temperatura Alta , Solanum lycopersicum/genética , Malondialdeído/metabolismo , Oxirredução , Estresse Oxidativo , Fotossíntese , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Plântula/genética , Plântula/fisiologia , Estresse Fisiológico , Água/metabolismo
11.
Genet Mol Res ; 13(2): 4022-35, 2014 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-24938613

RESUMO

The genomic expression profile of the super-hybrid rice Liangyoupeijiu female parent Pei'ai 64S in different tissues at different developmental stages under low temperature, drought, and high temperature stresses were detected using an Affymetrix GeneChip Rice Genome Array to screen upregulated and downregulated genes. In this study, we screened the drought-resistant gene OsRCI2-5, after which a constitutive OsRCI2-5 construct was created and transferred into Nipponbare. After polyethylene glycol-6000 and drought treatment, we found that the OsRCI2-5 gene improved the drought resistance of Nipponbare. Gene expression profiling showed that the OsRCI2-5 gene was expressed in the rice leaves, stems, and flower organs. Subcellular localization revealed that the gene was located in the membranes, and hence, we can deduce that a membrane signal peptide was responsible for signal transduction.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Transdução de Sinais/genética , Secas , Genoma de Planta/genética , Folhas de Planta/metabolismo , Estresse Fisiológico/genética , Temperatura
12.
Indian J Pharm Sci ; 75(6): 672-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24591742

RESUMO

A high-performance liquid chromatography method was developed for the determination of related substances in an intravenous emulsion loaded with a paclitaxel-cholesterol complex. The separation was achieved using Agilent Eclipse XDB-C18 column (150×4.6 mm, 3.5 µm), which was kept at 40°. The gradient mobile phase consisted of acetonitrile and water with a flow rate of 1.2 ml/min. The ultraviolet detection wavelength was set at 227 nm. The preparation of the sample solution began with the addition of anhydrous sodium sulphate to break the emulsion. Then, methanol and ethyl ether were added to pick up the drug and remove the accessories of the emulsion by extraction and centrifugation. Finally, paclitaxel was enriched by a nitrogen blow method and resolved with a mixture of methanol:glacial acetic acid (200:1). The method was proven to be selective, sensitive, robust, linear, repeatable, accurate and suitable for the determination of paclitaxel-related substances in the emulsion formulations, and the major degradation products in the potential pharmaceutical product were 7-epipaclitaxel and 10-deacetylpaclitaxel.

13.
J Periodontal Res ; 46(2): 184-92, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21118416

RESUMO

BACKGROUND AND OBJECTIVE: Periodontitis is a multifactorial disease influenced partly by genetics. Activation of pattern recognition receptors (PRRs) can lead to the up-regulation of inflammatory pathways, resulting in periodontal tissue destruction. Hence, functional polymorphisms located in PRRs can explain differences in host susceptibility to periodontitis. This study investigated single nucleotide polymorphisms of PRRs including toll-like receptor (TLR)2 (G2408A), TLR4 (A896G), TLR9 (T1486C), TLR9 (T1237C) and CD14 (C260T) in patients with chronic periodontitis and in periodontally healthy subjects. METHODS: One-hundred and fourteen patients with chronic periodontitis and 77 periodontally healthy subjects were genotyped using TaqMan® allelic discrimination assays. Fisher's exact test and chi-square analyses were performed to compare genotype and allele frequencies. RESULTS: The frequency of subjects with the CC genotype of CD14 (C260T) (24.6% in the chronic periodontitis group vs. 13% in the periodontally healthy group) and those expressing the T allele of CD14 (C260T) (CT and TT) (75.4% in the chronic periodontitis group vs. 87% in the periodontally healthy group) was statistically different among groups (p = 0.04). Homozygocity for the C allele of the CD14 (C260T) polymorphism (CC) was associated with a two--fold increased susceptibility to periodontitis (p = 0.04; odds ratio, 2.49; 95% confidence interval, 1.06-6.26). Individuals with the CC genotype of TLR9 (T1486C) (14.9% in the chronic periodontitis group vs. 28.6% in the periodontally healthy group) and those expressing the T allele of TLR9 (T1486C) (CT and TT) (85.1% in the chronic periodontitis group vs. 71.4% in the periodontally healthy group) were also significantly differently distributed between groups without adjustment (p = 0.03). Further analysis of nonsmokers revealed a significant difference in the distribution of genotypes between groups for TLR9 (T1486C; p = 0.017) and CD14 (C260T; p = 0.03), polymorphisms again without adjustment. CONCLUSION: The CC genotype of CD14 (C260T) is related to susceptibility to chronic periodontitis in Caucasians. In addition, differences observed in the distribution of TLR9 (T1486C) genotypes between groups warrant further investigation.


Assuntos
Periodontite Crônica/genética , Receptores de Lipopolissacarídeos/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores Toll-Like/genética , Adenina , Citosina , Índice de Placa Dentária , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Guanina , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/genética , Índice Periodontal , Bolsa Periodontal/genética , Fumar , Timina , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Receptor Toll-Like 9/genética
14.
Mol Oral Microbiol ; 25(2): 123-35, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20331800

RESUMO

Toll-like receptor 9 (TLR9) expression is increased in periodontally diseased tissues compared with healthy sites indicating a possible role of TLR9 and its ligand, bacterial DNA (bDNA), in periodontal disease pathology. Here, we determine the immunostimulatory effects of periodontal bDNA in human monocytic cells (THP-1). THP-1 cells were stimulated with DNA of two putative periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia. The role of TLR9 in periodontal bDNA-initiated cytokine production was determined either by blocking TLR9 signaling in THP-1 cells with chloroquine or by measuring IL-8 production and nuclear factor-kappaB (NF-kappaB) activation in HEK293 cells stably transfected with human TLR9. Cytokine production (IL-1beta, IL-6, and TNF-alpha) was increased significantly in bDNA-stimulated cells compared with controls. Chloroquine treatment of THP-1 cells decreased cytokine production, suggesting that TLR9-mediated signaling pathways are operant in the recognition of DNA from periodontal pathogens. Compared with native HEK293 cells, TLR9-transfected cells demonstrated significantly increased IL-8 production (P < 0.001) and NF-kappaB activation in response to bDNA, further confirming the role of TLR9 in periodontal bDNA recognition. The results of PCR arrays demonstrated upregulation of proinflammatory cytokine and NF-kappaB genes in response to periodontal bDNA in THP-1 cells, suggesting that cytokine induction is through NF-kappaB activation. Hence, immune responses triggered by periodontal bacterial nucleic acids may contribute to periodontal disease pathology by inducing proinflammatory cytokine production through the TLR9 signaling pathway.


Assuntos
Bacteroides/imunologia , Citocinas/biossíntese , DNA Bacteriano/imunologia , Porphyromonas gingivalis/imunologia , Receptor Toll-Like 9/fisiologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Rim/citologia , Rim/embriologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Transfecção , Fator de Necrose Tumoral alfa/biossíntese
15.
Bull Environ Contam Toxicol ; 82(2): 167-71, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18773129

RESUMO

A total of 10 surface soil samples representing the entire area of Linfen City were collected and analyzed for the presence of 16 polycyclic aromatic hydrocarbons. The total polycyclic aromatic hydrocarbon concentration ranged from 1.1 to 63.7 microg g(-1). Analysis of the sources of contamination revealed that polycyclic aromatic hydrocarbons in the soil were derived from combustion sources. Specifically, the primary source of polycyclic aromatic hydrocarbons was coal combustion, but the samples were also effected to varying degrees by traffic emissions. Furthermore, increased levels of contamination were observed in northeast Linfen due to the distribution of industrial plants.


Assuntos
Compostos Policíclicos/análise , Poluentes do Solo/análise , China
16.
Bull Environ Contam Toxicol ; 82(2): 162-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18773130

RESUMO

This study was conducted to determine the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in sandstorm depositions in Beijing, China. The PAH concentrations in 13 samples collected in Beijing ranged from 0.18 to 3.52 microg g(-1). Analysis of the sources of contamination revealed that the PAHs were derived from a coal combustion source, although various effects of traffic emissions were also observed. Furthermore, the PAH levels in Beijing tended to be higher in the southeast. Finally, the nemerow composite index revealed that the degree of pollution in the sandstorm depositions varied widely among sampling sites.


Assuntos
Compostos Policíclicos/análise , China , Dióxido de Silício
17.
Bull Environ Contam Toxicol ; 81(6): 599-603, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18779914

RESUMO

Ten soil samples collected in Linfen were analyzed for 21 organochlorine pesticides. The concentration of total organochlorine pesticides ranged from 4.3 to 23.2 ng g(-1) in soil from urban areas and from 26.3 to 247.4 ng g(-1) in soil from industrial plants. The highest levels of contamination were observed in northwest and central Linfen, reflecting the distribution of industrial plants. The HCH and DDT profiles revealed that the sources were associated mainly with lindane and technical DDT, respectively, while HCHs in the soil of industrial plants might originate from a new source.


Assuntos
Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes do Solo/análise , China , Cidades , Monitoramento Ambiental , Hidrocarbonetos Clorados/química , Indústrias , Praguicidas/química , Poluentes do Solo/química
18.
Plant Physiol Biochem ; 44(11-12): 837-43, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17097883

RESUMO

The effects of chilling on respiration (SHAM-resistant, cytochrome pathway and KCN-resistant, alternative pathway), temperature sensitivity, relative electrolyte conductivity, and degrees of oxidative stress (H(2)O(2) and malonaldehyde (MDA) contents) were separately examined in leaves and roots of cucumber (Cucumis sativus L.). After chilling at 8 degrees C for 4 days, both total respiration and KCN-resistant respiration in roots increased at different measurement temperatures. In contrast, SHAM-resistant respiration remained unchanged. In comparison, chilling significantly decreased the total respiration in leaves and this decrease was mostly due to a decrease in SHAM-resistant respiration. Chilling apparently decreased the sensitivity of KCN-resistant respiration to changes of temperature. The reduction levels of ubiquinone pool (UQr/UQt) increased both in chilled leaves and roots whilst pyruvate content increased only in chilled roots, but not in chilled leaves. Furthermore increases of H(2)O(2) and MDA contents were much greater in leaves than in roots. The same trend was also observed for ion leakage from tissues. Taken together, the results suggested that the higher chilling tolerance of roots was associated with their high total respiration and KCN-resistant respiration.


Assuntos
Cucumis sativus/metabolismo , Consumo de Oxigênio , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Temperatura Baixa , Resistência a Medicamentos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Cianeto de Potássio/farmacologia , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
19.
Clin Genet ; 63(2): 150-3, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12630964

RESUMO

Usher syndrome (USH) is characterized by the associated findings of hearing loss and retinitis pigmentosa (RP), leading to progressive loss of vision. Three forms of USH can be distinguished clinically. In the most severe form, USH1, profound congenital deafness is associated with vestibular dysfunction and RP. To determine the frequency of USH1C mutations as a cause for USH1, 128 probands with Usher syndrome type 1 including seven from Acadian and 121 from non-Acadian populations were systematically screened for mutations in USH1C using a combined single-strand conformational polymorphisms (SSCP)/heteroduplex and sequencing method. All seven Acadian USH1 patients were found to be homozygous for both the 216G>A mutation and the 9-repeat VNTR which characterizes the Acadian allele, confirming previous evidence for a founder effect by haplotype analysis. However, USH1C mutations were identified in only two non-Acadian USH1 probands (1.65%) including one from Pakistan who was homozygous for a 238-239insC mutation and one from Canada was also homozygous for the Acadian allele. The low prevalence of USH1C mutations in the present study suggests that the high prevalence of the 238-239insC in Germany may reflect a founder effect. Comparison of the affected haplotypes in the Canadian patient with the Acadian USH1 patients yielded evidence for a founder effect. Our data suggest that USH1C is a relatively rare form of USH1 in non-Acadian populations and that in addition to the 216G>A Acadian mutation, the 238-239insC mutation appears to be common in some populations.


Assuntos
Proteínas de Transporte/genética , Efeito Fundador , Perda Auditiva/genética , Retinose Pigmentar/genética , Proteínas Adaptadoras de Transdução de Sinal , Alelos , Proteínas de Ciclo Celular , Mapeamento Cromossômico , Proteínas do Citoesqueleto , Análise Mutacional de DNA , Perda Auditiva/complicações , Perda Auditiva/epidemiologia , Humanos , Louisiana/epidemiologia , Polimorfismo Conformacional de Fita Simples , Quebeque/etnologia , Retinose Pigmentar/complicações , Retinose Pigmentar/epidemiologia
20.
Hum Mol Genet ; 10(25): 2945-51, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11741837

RESUMO

Mutations in four members of the connexin gene family have been shown to underlie distinct genetic forms of deafness, including GJB2 [connexin 26 (Cx26)], GJB3 (Cx31), GJB6 (Cx30) and GJB1 (Cx32). We have found that alterations in a fifth member of this family, GJA1 (Cx43), appear to cause a common form of deafness in African Americans. We identified two different GJA1 mutations in four of 26 African American probands. Three were homozygous for a Leu-->Phe substitution in the absolutely conserved codon 11, whereas the other was homozygous for a Val-->Ala transversion at the highly conserved codon 24. Neither mutation was detected in DNA from 100 control subjects without deafness. Cx43 is expressed in the cochlea, as is demonstrated by PCR amplification from human fetal cochlear cDNA and by RT-PCR of mouse cochlear tissues. Immunohistochemical staining of mouse cochlear preparations showed immunostaining for Cx43 in non-sensory epithelial cells and in fibrocytes of the spiral ligament and the spiral limbus. To our knowledge this is the first alpha connexin gene to be associated with non-syndromic deafness. Cx43 must also play a critical role in the physiology of hearing, presumably by participating in the recycling of potassium to the cochlear endolymph.


Assuntos
Cóclea/metabolismo , Conexina 43/genética , Surdez/genética , Mutação/genética , Sequência de Aminoácidos , Animais , Conexina 26 , Conexina 43/metabolismo , Conexinas , Análise Mutacional de DNA , Primers do DNA/química , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Síndrome
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