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1.
Cell Commun Signal ; 22(1): 259, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715050

RESUMEN

Ubiquitination and deubiquitination are important forms of posttranslational modification that govern protein homeostasis. Deubiquitinating enzymes (DUBs), a protein superfamily consisting of more than 100 members, deconjugate ubiquitin chains from client proteins to regulate cellular homeostasis. However, the dysregulation of DUBs is reportedly associated with several diseases, including cancer. The tumor microenvironment (TME) is a highly complex entity comprising diverse noncancerous cells (e.g., immune cells and stromal cells) and the extracellular matrix (ECM). Since TME heterogeneity is closely related to tumorigenesis and immune evasion, targeting TME components has recently been considered an attractive therapeutic strategy for restoring antitumor immunity. Emerging studies have revealed the involvement of DUBs in immune modulation within the TME, including the regulation of immune checkpoints and immunocyte infiltration and function, which renders DUBs promising for potent cancer immunotherapy. Nevertheless, the roles of DUBs in the crosstalk between tumors and their surrounding components have not been comprehensively reviewed. In this review, we discuss the involvement of DUBs in the dynamic interplay between tumors, immune cells, and stromal cells and illustrate how dysregulated DUBs facilitate immune evasion and promote tumor progression. We also summarize potential small molecules that target DUBs to alleviate immunosuppression and suppress tumorigenesis. Finally, we discuss the prospects and challenges regarding the targeting of DUBs in cancer immunotherapeutics and several urgent problems that warrant further investigation.


Asunto(s)
Enzimas Desubicuitinizantes , Microambiente Tumoral , Humanos , Enzimas Desubicuitinizantes/metabolismo , Evasión Inmune , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/enzimología , Neoplasias/metabolismo , Escape del Tumor , Microambiente Tumoral/inmunología , Ubiquitinación
2.
Cancer Cell Int ; 23(1): 63, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37038218

RESUMEN

BACKGROUND: Autophagy related protease 4B (ATG4B) is a protease required for autophagy processing, which is strongly implicated in cancer progression.  Phosphorylation of ATG4B is crucial for activation of its protease activity.  However, little is known about the relationship of ATG4B and its phosphorylated form at Ser 383 and 392 sites (pS383/392-ATG4B), with clinical outcomes, particularly in colorectal cancer (CRC). METHODS: The ATG4B gene expression in CRC patients was obtained from The Cancer Genome Atlas (TCGA) database to analyze its clinical relevance. Tissue microarrays composed of 118 CRC patient specimens were used to determine the associations of ATG4B and pS383/392-ATG4B protein levels with prognosis. The biological functions of ATG4B in CRC cells were inspected with cell proliferation, mobility and spheroid culture assays. RESULTS: ATG4B gene expression was elevated in tumor tissues of CRC patients compared to that in adjacent normal tissues and high level of ATG4B expression was associated with poor survival. Similarly, protein levels of ATG4B and pS383/392-ATG4B were highly correlated with worse overall survival and disease-free survival. Stratification analysis results showed that high level of ATG4B had significantly higher risk of mortality in males and elderly patients compared to those female patients and patients 60 years or younger. In contrast, multivariate Cox's regression analysis indicated that high level of pS383/392-ATG4B was significantly linked to unfavorable overall survival and disease-free survival of males and elderly patients, whereas, it had no correlation with female patients and patients 60 years or younger. Moreover, high level of ATG4B was positively associated with increased mortality risk in patients with advanced AJCC stages (III and IV) and lymph node invasion (N1 and N2) for both overall survival and disease-free survival. Nevertheless, high level of pS383/392-ATG4B was positively correlated with increased mortality risk in patients with early AJCC stages (I and II) and without lymph node invasion (N0). In addition, silencing ATG4B attenuated migration, invasion, and further enhanced the cytotoxic effects of chemotherapeutic drugs in two and three-dimensional cultures of CRC cells. CONCLUSIONS: Our results suggest that ATG4B and pS383/392-ATG4B might be suitable biomarkers and therapeutic targets for CRC.

3.
Environ Toxicol ; 38(8): 2022-2030, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37163415

RESUMEN

Breast cancer is a leading cause of cancer-related death worldwide, and chemoresistance often leads to poor patient outcomes. In this study, we investigated the anticancer activity of synthetic diphenyl disulfide (DPDS) in breast cancer cell lines. DPDS inhibited cellular proliferation and viability in a dose-dependent manner and reduced colony formation, an index of clonogenicity. Annexin-V and 7-AAD double staining showed that DPDS could induce the apoptosis of breast cancer cells. Western blotting of the expression of Bax p21 and its cleaved form p18 suggested the activation of p18 Bax-induced apoptosis. Furthermore, the increased expression of the autophagy marker LC3B-II indicated autophagic lysosome accumulation induced by DPDS. Our findings suggest that DPDS has potential as a candidate for treating breast cancer, and further modifications and optimizations are warranted.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Proteína X Asociada a bcl-2 , Neoplasias de la Mama/metabolismo , Apoptosis , Proliferación Celular , Autofagia , Línea Celular Tumoral
4.
Int J Mol Sci ; 22(1)2020 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33379248

RESUMEN

Curcumin is one of the most valuable natural products due to its pharmacological activities. However, the low bioavailability of curcumin has long been a problem for its medicinal use. Large studies have been conducted to improve the use of curcumin; among these studies, curcumin metabolites have become a relatively new research focus over the past few years. Additionally, accumulating evidence suggests that curcumin or curcuminoid metabolites have similar or better biological activity than the precursor of curcumin. Recent studies focus on the protective role of plasma tetrahydrocurcumin (THC), a main metabolite of curcumin, against tumors and chronic inflammatory diseases. Nevertheless, studies of THC in eye diseases have not yet been conducted. Since ophthalmic conditions play a crucial role in worldwide public health, the prevention and treatment of ophthalmic diseases are of great concern. Therefore, the present study investigated the antioxidative, anti-inflammatory, antiangiogenic, and neuroprotective effects of THC on four major ocular diseases: age-related cataracts, glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR). While this study aimed to show curcumin as a promising potential solution for eye conditions and discusses the involved mechanistic pathways, further work is required for the clinical application of curcumin.


Asunto(s)
Curcumina/análogos & derivados , Oftalmopatías/tratamiento farmacológico , Curcumina/metabolismo , Curcumina/uso terapéutico , Humanos , Oftalmología
5.
Molecules ; 25(17)2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32825798

RESUMEN

Prolonged treatment with cisplatin (CDDP) frequently develops chemoresistance. We have previously shown that p22phox, an endoplasmic reticulum (ER) membrane protein, confers CDDP resistance by blocking CDDP nuclear entry in oral squamous cell carcinoma (OSCC) cells; however, the underlying mechanism remains unresolved. Using a fluorescent dye-labeled CDDP, here we show that CDDP can bind to p22phox in both cell-based and cell-free contexts. Subsequent detection of CDDP-peptide interaction by the Tris-Tricine-based electrophoresis revealed that GA-30, a synthetic peptide matching a region of the cytosolic domain of p22phox, could interact with CDDP. These results were further confirmed by liquid chromatography-mass spectrometry (LC-MS) analysis, from which MA-11, an 11-amino acid subdomain of the GA-30 domain, could largely account for the interaction. Amino acid substitutions at Cys50, Met65 and Met73, but not His72, significantly impaired the binding between CDDP and the GA-30 domain, thereby suggesting the potential CDDP-binding residues in p22phox protein. Consistently, the p22phox point mutations at Cys50, Met65 and Met73, but not His72, resensitized OSCC cells to CDDP-induced cytotoxicity and apoptosis. Finally, p22phox might have binding specificity for the platinum drugs, including CDDP, carboplatin and oxaliplatin. Together, we have not only identified p22phox as a novel CDDP-binding protein, but further highlighted the importance of such a drug-protein interaction in drug resistance.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias de la Boca/tratamiento farmacológico , NADPH Oxidasas/metabolismo , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/metabolismo , Antineoplásicos/administración & dosificación , Antineoplásicos/metabolismo , Apoptosis , Carboplatino/administración & dosificación , Carboplatino/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Proliferación Celular , Cisplatino/administración & dosificación , Cisplatino/metabolismo , Retículo Endoplásmico/metabolismo , Humanos , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , NADPH Oxidasas/genética , Oxaliplatino/administración & dosificación , Oxaliplatino/metabolismo , Células Tumorales Cultivadas
6.
Cancer Cell Int ; 19: 87, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30996687

RESUMEN

BACKGROUND: To determine the association between circadian pathway genetic variants and the risk of prostate cancer progression. METHODS: We systematically evaluated 79 germline variants in nine circadian pathway genes in a cohort of 458 patients with localized prostate cancer as the discovery phase. We then replicated the significant findings in another cohort of 324 men with more advanced disease. The association of each variant with prostate cancer progression was evaluated by a log-rank test and Cox regression. RESULTS: A single nucleotide polymorphism of the neuronal PAS domain protein 2 (NPAS2) gene (rs6542993 A>T) was found to be associated with a significantly higher risk of disease progression in both localized (P = 0.001) and advanced (P = 0.039) prostate cancer cases. In silico analysis revealed decreased expression levels of NPAS2 in carriers of the T allele of rs6542993 compared with those carrying the A allele. Consistently, downregulation of NPAS2 expression was associated with more aggressive prostate cancer and poor progression-free survival (log-rank P = 0.002). CONCLUSIONS: The NPAS2 rs6542993 polymorphism may be a promising biomarker, and may shed light on the pathways that govern prostate cancer progression.

7.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-30974814

RESUMEN

Manganese-dependent superoxide dismutase (MnSOD, SodA) and iron-dependent SOD (FeSOD, SodB) are critical cytosolic enzymes for alleviating superoxide stress. Distinct from the singular sodA gene in most bacteria, Stenotrophomonas maltophilia harbors two sodA genes, sodA1 and sodA2. The roles of SodA1, SodA2, and SodB of S. maltophilia in alleviating superoxide stress were investigated. The expression of sod genes was determined by promoter-xylE transcriptional fusion assay and qRT-PCR. SodA2 and sodB expressions were proportional to the bacterial logarithmic growth, but unaffected by menadione (MD), iron, or manganese challenges. SodA1 was intrinsically unexpressed and inducibly expressed by MD. Complementary expression of sodA1 was observed when sodA2 was inactivated. The individual or combined sod deletion mutants were constructed using the gene replacement strategy. The functions of SODs were assessed by evaluating cell viabilities of different sod mutants in MD, low iron-stressed, and/or low manganese-stressed conditions. Inactivation of SodA1 or SodA2 alone did not affect bacterial viability; however, simultaneously inactivating sodA1 and sodA2 significantly compromised bacterial viability in both aerobic growth and stressed conditions. SodA1 can either rescue or support SodA2 when SodA2 is defective or insufficiently potent. The presence of two MnSODs gives S. maltophilia an advantage against superoxide stress.


Asunto(s)
Proteínas Bacterianas/metabolismo , Estrés Oxidativo , Stenotrophomonas maltophilia/enzimología , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo , Proteínas Bacterianas/genética , Stenotrophomonas maltophilia/genética , Superóxido Dismutasa/genética
8.
Int J Mol Sci ; 20(10)2019 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-31121863

RESUMEN

The endoplasmic reticulum (ER) has diverse functions, and especially misfolded protein modification is in the focus of this review paper. With a highly regulatory mechanism, called unfolded protein response (UPR), it protects cells from the accumulation of misfolded proteins. Nevertheless, not only does UPR modify improper proteins, but it also degrades proteins that are unable to recover. Three pathways of UPR, namely PERK, IRE-1, and ATF6, have a significant role in regulating stress-induced physiological responses in cells. The dysregulated UPR may be involved in diseases, such as atherosclerosis, heart diseases, amyotrophic lateral sclerosis (ALS), and cancer. Here, we discuss the relation between UPR and cancer, considering several aspects including survival, dormancy, immunosuppression, angiogenesis, and metastasis of cancer cells. Although several moderate adversities can subject cancer cells to a hostile environment, UPR can ensure their survival. Excessive unfavorable conditions, such as overloading with misfolded proteins and nutrient deprivation, tend to trigger cancer cell death signaling. Regarding dormancy and immunosuppression, cancer cells can survive chemotherapies and acquire drug resistance through dormancy and immunosuppression. Cancer cells can also regulate the downstream of UPR to modulate angiogenesis and promote metastasis. In the end, regulating UPR through different molecular mechanisms may provide promising anticancer treatment options by suppressing cancer proliferation and progression.


Asunto(s)
Neoplasias/patología , Respuesta de Proteína Desplegada , Animales , Supervivencia Celular , Progresión de la Enfermedad , Humanos , Tolerancia Inmunológica , Metástasis de la Neoplasia/inmunología , Metástasis de la Neoplasia/patología , Metástasis de la Neoplasia/terapia , Neoplasias/inmunología , Neoplasias/metabolismo , Neoplasias/terapia , Neovascularización Patológica/inmunología , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Neovascularización Patológica/terapia
9.
Int J Mol Sci ; 20(7)2019 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-30987073

RESUMEN

Current clinical challenges of prostate cancer management are to restrict tumor growth and prohibit metastasis. AICAR (5-aminoimidazole-4-carbox-amide-1-ß-d-ribofuranoside), an AMP-activated protein kinase (AMPK) agonist, has demonstrated antitumor activities for several types of cancers. However, the activity of AICAR on the cell growth and metastasis of prostate cancer has not been extensively studied. Herein we examine the effects of AICAR on the cell growth and metastasis of prostate cancer cells. Cell growth was performed by MTT assay and soft agar assay; cell apoptosis was examined by Annexin V/propidium iodide (PI) staining and poly ADP ribose polymerase (PARP) cleavage western blot, while cell migration and invasion were evaluated by wound-healing assay and transwell assay respectively. Epithelial-mesenchymal transition (EMT)-related protein expression and AMPK/mTOR-dependent signaling axis were analyzed by western blot. In addition, we also tested the effect of AICAR on the chemosensitivity to docetaxel using MTT assay. Our results indicated that AICAR inhibits cell growth in prostate cancer cells, but not in non-cancerous prostate cells. In addition, our results demonstrated that AICAR induces apoptosis, attenuates transforming growth factor (TGF)-ß-induced cell migration, invasion and EMT-related protein expression, and enhances the chemosensitivity to docetaxel in prostate cancer cells through regulating the AMPK/mTOR-dependent pathway. These findings support AICAR as a potential therapeutic agent for the treatment of prostate cancer.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Ribonucleótidos/farmacología , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Aminoimidazol Carboxamida/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Docetaxel/farmacología , Sinergismo Farmacológico , Transición Epitelial-Mesenquimal/efectos de los fármacos , Humanos , Masculino , Invasividad Neoplásica , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología
10.
Int J Mol Sci ; 18(3)2017 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-28245560

RESUMEN

Deubiquitinases (DUBs) play a critical role in ubiquitin-directed signaling by catalytically removing the ubiquitin from substrate proteins. Ubiquitin-specific protease 15 (USP15), a member of the largest subfamily of cysteine protease DUBs, contains two conservative cysteine (Cys) and histidine (His) boxes. USP15 harbors two zinc-binding motifs that are essential for recognition of poly-ubiquitin chains. USP15 is grouped into the same category with USP4 and USP11 due to high degree of homology in an N-terminal region consisting of domains present in ubiquitin-specific proteases (DUSP) domain and ubiquitin-like (UBL) domain. USP15 cooperates with COP9 signalosome complex (CSN) to maintain the stability of cullin-ring ligase (CRL) adaptor proteins by removing the conjugated ubiquitin chains from RBX1 subunit of CRL. USP15 is also implicated in the stabilization of the human papillomavirus type 16 E6 oncoprotein, adenomatous polyposis coli, and IκBα. Recently, reports have suggested that USP15 acts as a key regulator of TGF-ß receptor-signaling pathways by deubiquitinating the TGF-ß receptor itself and its downstream transducers receptor-regulated SMADs (R-SMADs), including SMAD1, SMAD2, and SMAD3, thus activating the TGF-ß target genes. Although the importance of USP15 in pathologic processes remains ambiguous so far, in this review, we endeavor to summarize the literature regarding the relationship of the deubiquitinating action of USP15 with the proteins involved in the regulation of Parkinson's disease, virus infection, and cancer-related signaling networks.


Asunto(s)
Susceptibilidad a Enfermedades , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitinación , Animales , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Mapeo Cromosómico , Resistencia a Antineoplásicos/genética , Expresión Génica , Regulación de la Expresión Génica , Humanos , Espacio Intracelular , Isoenzimas , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Transporte de Proteínas , Transducción de Señal , Relación Estructura-Actividad , Proteasas Ubiquitina-Específicas/química , Proteasas Ubiquitina-Específicas/genética
12.
J Neuroeng Rehabil ; 13: 25, 2016 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-26969526

RESUMEN

BACKGROUND: Cerebral palsy (CP) is the most common pediatric disease to cause motor disability. Two common symptoms in CP are spasticity and contracture. If this occurred in the ankle plantar flexors of children with CP, it will impair their gait and active daily living profoundly. Most children with CP receive botulinum toxin type A (BoNT-A) injection to reduce muscle tone, but a knowledge gap exists in the understanding of changes of neural and non-neural components of spasticity after injection. The purpose of this study was to determine if our device for quantitative modified Tardieu approach (QMTA) is a valid method to assess spasticity of calf muscles after botulinum toxin injection. METHODS: In this study, we intended to develop a device for quantitative measurement of spasticity in calf muscles based on the modified Tardieu scale (MTS) and techniques of biomedical engineering. Our QMTA measures the angular displacement and resistance of stretched joint with a device that is light, portable and can be operated similar to conventional approaches for MTS. The static (R2), dynamic (R1) and R2-R1 angles derived from the reactive signals collected by the miniature sensors are used to represent the non-neural and neural components of stretched spastic muscles. Four children with CP were recruited to assess the change in spasticity in their gastrocnemius muscles before and 4 weeks after BoNT-A injection. RESULTS: A simulated ankle model validated the performance of our device in measuring joint displacement and estimating the angle of catch. Data from our participants with CP showed that R2 and R2-R1 improved significantly after BoNT-A administration. It indicates both neural and non-neural components of the spastic gastrocnemius muscles improved at four weeks after BoNT-A injection in children with CP. CONCLUSION: Our device for QMTA can objectively measure the changes in spasticity of the gastrocnemius muscle in children with cerebral palsy after BoNT-A injection.


Asunto(s)
Acelerometría/instrumentación , Toxinas Botulínicas Tipo A/uso terapéutico , Parálisis Cerebral/tratamiento farmacológico , Fármacos Neuromusculares/uso terapéutico , Adolescente , Parálisis Cerebral/complicaciones , Niño , Preescolar , Marcha/efectos de los fármacos , Humanos , Masculino , Espasticidad Muscular/tratamiento farmacológico , Espasticidad Muscular/etiología , Músculo Esquelético/efectos de los fármacos , Proyectos Piloto
13.
J Gastroenterol Hepatol ; 30(5): 879-84, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-23808794

RESUMEN

BACKGROUND AND AIM: Chronic hepatitis C virus (HCV) infection has been suggested to be associated with non-insulin-dependent diabetes mellitus and lipid profiles. This study aimed to investigate the possible relationships of insulin resistance (IR) and lipid profiles with chronic hepatitis C (CHC) patients in Taiwan. METHODS: We enrolled 160 hospital-based CHC patients with liver biopsy and the 480 controlled individuals without CHC and chronic hepatitis B from communities without known history of non-insulin-dependent diabetes mellitus. Fasting plasma glucose, total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TGs), alanine aminotransferase, and serum insulin levels, and homeostasis model assessment (HOMA-IR) were tested. RESULTS: When comparing factors between CHC patients, and sex- and age-matched controls who had no HCV infection, patients with HCV infection had a significantly higher alanine aminotransferase level, fasting plasma glucose level, insulin level, and HOMA-IR (P < 0.001, P = 0.023, P = 0.017, and P = 0.011, respectively), and significantly lower TG level (P = 0.023), total cholesterol, and HDL-C and LDL-C levels (all P < 0.001) than 480 controls. In multivariate logistic regression analyses, a low total cholesterol, a low TGs, and a high HOMA-IR are independent factors significantly associated with chronic HCV infection. In the 160 CHC patients (41 patients with high HOMA-IR [> 2.5]), a high body mass index, TGs, and HCV RNA level are independent factors significantly associated with high HOMA-IR in multivariate logistic analyses. CONCLUSIONS: Chronic HCV infection was associated with metabolic characteristics including IR and lipid profile. IR was also associated with virological characteristics.


Asunto(s)
Hepatitis C Crónica/metabolismo , Resistencia a la Insulina , Lípidos/sangre , Adulto , Alanina Transaminasa/sangre , Glucemia , Índice de Masa Corporal , Femenino , Hepatitis C Crónica/fisiopatología , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad , Análisis Multivariante
14.
Cancer Cell Int ; 14(1): 1, 2014 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-24393431

RESUMEN

The anticancer effects of ceramide have been reported in many types of cancers but less in lung cancer. In this study, we used C2-ceramide to further investigate its possible anticancer effects and mechanisms on non-small cell lung cancer (NSCLC) H1299 cells. The result of cell proliferation in terms of trypan blue assay showed high dose of C2-ceramide inhibited cell survival after 24 h treatment. The flow cytometry-based assays indicated the effect of apoptosis, chromatin condensation, and G1 arrest in terms of Annexin V/propidium iodide (PI), DAPI, and PI stainings, respectively. Moreover, the decreased protein level of p-Akt, p-NFκB, survivin and cyclin A2 were detected by Western blot assay. Taken together, these results indicated the antiproliferative effect of C2-ceramide is majorly responsible for cell apoptosis in lung cancer H1299 cells.

15.
Virus Genes ; 49(1): 30-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24792512

RESUMEN

The hepatitis B virus (HBV) genomes in Taiwanese aborigines, whose ancestors have lived in Taiwan for over 10,000 years, have not been characterized. In order to characterize of HBV in this special population, serum samples were obtained from serologically HBsAg-positive 27 Taiwanese aborigines. The pre-S1/S2 region and the full-length 3.2 kb of the HBV genome were amplified by PCR. Obtained amplicons were sequenced and confirmed the HBV genotypes by phylogenetic analysis. By phylogenetic analysis of the sequence of pre-S1/pre-S2 region, HBV/B2 (21/27: 78 %) was the most prevalent followed by genotype D (6/27: 22 %). Two strains of HBV/B2, each having 3,215 bp genomes, had recombination with genotype C in the pre-C/C gene which is characteristic of subgenotype B2 circulating in Southeast Asia. Interestingly, six strains of genotype D formed a distinct cluster between subgenotypes D1 and D2 suggesting a novel group of HBV. A similar finding could also be confirmed based on the entire 3,182 bp genome from four strains of HBV/D. This new cluster was supported by a branch with 99 % bootstrap value and 3.4-5.8 % nucleotide divergence over the entire genome from other known subgenotypes D1 to D9. Four strains of the new D subgenotype showed serotype ayw2, but had unique amino acid sequences consisting of N115 in the preS/S gene; P41 in the X gene; S239, K/E295, V567, and P708 in the P gene, respectively. From the above results, we provisionally proposed to designate it as novel quasi-subgenotype D2 identified in Taiwanese aborigines.


Asunto(s)
Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B/virología , Adulto , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , ADN Viral/química , ADN Viral/genética , Femenino , Genoma Viral , Genotipo , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Historia Medieval , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Grupos de Población , Análisis de Secuencia de ADN , Homología de Secuencia , Taiwán
16.
J Anesth ; 28(4): 559-68, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24337933

RESUMEN

PURPOSE: Multi-modality electrophysiological techniques were performed to assess the effects of quinidine on peripheral nerve conduction. METHODS: Twenty-seven rats were treated with 1, 3, and 5 µmol quinidine in 0.1 ml 5 % glucose. The mixed-nerve somato-sensory evoked potential (M-SSEP), dermatomal-SSEP (D-SSEP), and compound muscle action potentials (CMAP) were evoked and recorded. After positioning Gelfoam strips saturated with quinidine and 5 % glucose around the left and right sciatic nerves, potentials were measured at baseline, immediately after treatment, every 15 min for the 1st hour, and every 30 min for the next 3 h. After 2 weeks, the walking behaviors and potentials were again analyzed and myelinated fibers in the sciatic nerve were counted. RESULTS: Quinidine applied directly to sciatic nerves reduced the amplitude and prolonged the latency in SSEPs and CMAP, compared to baseline and the contralateral right limbs (controls). This persisted for at least 4 h. After 2 weeks, electrophysiological tests and walking behavior showed no significant difference between the controls and experimental limbs. There was also no difference in the number of myelinated fibers in the sciatic nerves. CONCLUSIONS: Quinidine decreases amplitude and prolongs latency in the sciatic nerve in a dose-related manner without local neural toxicity.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Antiarrítmicos/farmacología , Potenciales Evocados Somatosensoriales/efectos de los fármacos , Quinidina/farmacología , Nervio Ciático/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Lateralidad Funcional/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Fibras Nerviosas Mielínicas/efectos de los fármacos , Ratas , Ratas Wistar , Caminata
17.
Artículo en Inglés | MEDLINE | ID: mdl-38204236

RESUMEN

BACKGROUND: Buspirone is used for the management of depression and anxiety disorders. Due to its short half-life and low bioavailability, it requires multiple daily doses and is associated with some side effects. AIM: This study aimed to develop chitosan-based hydrogels as drug-controlled release carriers. OBJECTIVE: The objective of this study is to prepare chitosan-based hydrogels as controlled release carriers in order to overcome the side effects of buspirone HCl and improve patients' compliance and their life quality. METHODS: Polymer chitosan was polymerized with two monomers, acrylic acid and itaconic acid, to synthesize pH-sensitive hydrogel. The Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis were performed to confirm the structure formation and thermal stability. Water penetration capability and loading of the drug were performed by porosity and drug loading studies. The swelling and dissolution tests were performed to analyze the pH-sensitive nature of the developed hydrogels. RESULTS: FTIR, TGA, and DSC demonstrated that the chitosan-based hydrogels were successfully prepared. An increase in water penetration and drug loading into the hydrogel network was seen with the high incorporation of chitosan, acrylic acid, and itaconic acid. The swelling and dissolution studies revealed that prepared hydrogel offered the greatest swelling and drug release at a high pH of 7.4. The swelling and drug release from the hydrogel were affected by the concentrations of the incorporated contents. A controlled release of the drug was achieved by using chitosan-based hydrogel as a delivery carrier compared to commercial tablets of buspirone. CONCLUSION: The results showed that the developed chitosan-based hydrogel can be considered one of the most suitable drug carrier systems for the controlled delivery of buspirone.

18.
BMC Cancer ; 13: 330, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-23829168

RESUMEN

BACKGROUND: Post-surgery therapies are given to early-stage breast cancer patients due to the possibility of residual micrometastasis, and optimized by clincopathological parameters such as tumor stage, and hormone receptor/lymph node status. However, current efficacy of post-surgery therapies is unsatisfactory, and may be varied according to unidentified patient genetic factors. Increases of breast cancer occurrence and recurrence have been associated with dyslipidemia, which can attribute to other known risk factors of breast cancer including obesity, diabetes and metabolic syndrome. Thus we reasoned that dyslipidemia-associated nucleotide polymorphisms (SNPs) on the APOA1/C3/A5 gene cluster may predict breast cancer risk and tumor progression. METHODS: We analyzed the distribution of 5 selected APOA1/C3/A5 SNPs in recruited Taiwanese breast cancer patients (n=223) and healthy controls (n=162). The association of SNP (APOA1 rs670) showing correlation with breast cancer with baseline and follow-up parameters was further examined. RESULTS: APOA1 rs670 A allele carriage was higher in breast cancer patients than controls (59.64% vs. 48.77%, p=0.038). The rs670 A allele carrying patients showed less favorable baseline phenotype with positive lymph nodes (G/A: OR=3.32, 95% CI=1.77-6.20, p<0.001; A/A: OR=2.58, 95% CI=1.05-6.32, p=0.039) and negative hormone receptor expression (A/A: OR=4.85, 95%CI=1.83-12.83, p=0.001) in comparison to G/G carriers. Moreover, rs670 A/A carrying patients had higher risks in both tumor recurrence (HR=3.12, 95% CI=1.29-7.56, p=0.012) and mortality (HR=4.36, 95% CI=1.52-12.47, p=0.006) than patients with no A alleles after adjustments for associated baseline parameters. Furthermore, the prognostic effect of rs670 A/A carriage was most evident in lymph node-negative patients, conferring to the highest risks of recurrence (HR=4.98, 95% CI=1.40-17.70, p=0.013) and mortality (HR=9.87, 95%CI=1.60-60.81, p=0.014) than patients with no A alleles. CONCLUSIONS: APOA1 rs670 A/A carriage showed poor post-surgery prognosis in Taiwanese lymph node-negative breast cancer patients, whose prognosis were considered better and adjuvant treatment might be less stringent according to currently available assessment protocols. Our findings suggest that APOA1 rs670 indicate a post-surgery risk of breast cancer disease progression, and that carriers of this SNP may benefit from more advanced disease monitoring and therapy regimens than the current regular standards. Furthermore, control of lipid homeostasis might protect APOA1 rs670 minor allele carriers from breast cancer occurrence and progression.


Asunto(s)
Apolipoproteína A-I/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Apolipoproteína A-V , Apolipoproteína C-III/genética , Apolipoproteínas A/genética , Neoplasias de la Mama/mortalidad , Dislipidemias/genética , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Familia de Multigenes , Fenotipo , Reacción en Cadena en Tiempo Real de la Polimerasa , Taiwán , Resultado del Tratamiento
19.
Pharmaceutics ; 15(5)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37242688

RESUMEN

Linalool is an aromatic oil with analgesic, anti-inflammatory and anti-UVB-induced skin damage effects. The aim of this study was to develop a linalool-loaded microemulsion formulation for topical application. In order to quickly obtain an optimal drug-loaded formulation, statistical tools of the response surface methodology and a mixed experimental design with four independent variables of oil (X1), mixed surfactant (X2), cosurfactant (X3) and water (X4) were used to design a series of model formulations in order to analyze the effect of the composition on the characteristics and permeation capacity of linalool-loaded microemulsion formulations and to obtain an appropriate drug-loaded formulation. The results showed that the droplet size, viscosity and penetration capacity of linalool-loaded formulations were significantly affected by formulation component proportions. The skin deposition amount of the drug and flux of such formulations expressively increased about 6.1-fold and 6.5-fold, respectively, when compared to the control group (5% linalool dissolved in ethanol). After 3 months of storage, the physicochemical characteristics and drug level did not show a significant change. The linalool formulation-treated rat skin showed non-significant irritation compared to skin treatments in the distilled-water-treated group. The results showed that specific microemulsion applications might be considered as potential drug delivery carriers for essential oil topical application.

20.
ACS Omega ; 8(26): 23991-24002, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37426260

RESUMEN

The objective of this study is to design a polymeric network of nanogels for sustained release of caffeine. Therefore, alginate-based nanogels were fabricated by a free-radical polymerization technique for the sustained delivery of caffeine. Polymer alginate was crosslinked with monomer 2-acrylamido-2-methylpropanesulfonic acid by crosslinker N',N'-methylene bisacrylamide. The prepared nanogels were subjected to sol-gel fraction, polymer volume fraction, swelling, drug loading, and drug release studies. A high gel fraction was seen with the increasing feed ratio of polymer, monomer, and crosslinker. Greater swelling and drug release were observed at pH 4.6 and 7.4 as compared to pH 1.2 due to the deprotonation and protonation of functional groups of alginate and 2-acrylamido-2-methylpropanesulfonic acid. An increase was observed in swelling, loading, and release of the drug with the incorporation of a high feed ratio of polymer and monomer, while a reduction was seen with the increase in crosslinker feed ratio. Similarly, an HET-CAM test was used to evaluate the safety of the prepared nanogels, which showed that the prepared nanogels have no toxic effect on the chorioallantoic membrane of fertilized chicken eggs. Similarly, different characterizations techniques such as FTIR, DSC, SEM, and particle size analysis were carried out to determine the development, thermal stability, surface morphology, and particle size of the synthesized nanogels, respectively. Thus, we can conclude that the prepared nanogels can be used as a suitable agent for the sustained release of caffeine.

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