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1.
Chem Res Toxicol ; 37(6): 1053-1061, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38847154

ABSTRACT

Poisoning caused by the mushroom Amanita phalloides, due to the toxin α-amanitin, accounts for approximately 90% of food poisoning deaths in China with no specific antidotes. To investigate the role of salidroside (Sal) in α-amanitin (α-AMA)-induced mitophagy, mouse liver cells AML-12 were exposed to α-AMA in the presence of Sal or not. Intracellular reactive oxygen species (ROS) levels were measured using a ROS detection kit, mitochondrial activity was evaluated using a mitochondrial red fluorescent probe kit or JC-1 dye, and protein expression levels of PINK1, Parkin, LC3 II, P62, Bax, Bcl-2, Caspase 3, Cleaved-Caspase 3, PARP I, and Cleaved-PARP I were detected through Western blot. Results demonstrated that α-AMA led to increased intracellular ROS levels, cell apoptosis, and decreased mitochondrial membrane potential. Notably, expression levels of mitophagy-related proteins PINK1, Parkin, and LC3 increased significantly while the P62 protein expression decreased remarkably. Furthermore, Sal reversed the α-AMA-induced decrease in cell viability and mitochondrial membrane potential and increase in intracellular ROS level. In addition, Sal promoted expression levels of PINK1, Parkin, and LC3 II while suppressing the Bax/Bcl-2 ratio, Cleaved-Caspase 3, and Cleaved-PARP I as well as P62. The results above proved that salidroside alleviates α-AMA-induced mouse liver cells damage via promoting PINK1/Parkin-mediated mitophagy and reducing cell apoptosis.


Subject(s)
Apoptosis , Glucosides , Mitochondria , Mitophagy , Phenols , Protein Kinases , Reactive Oxygen Species , Ubiquitin-Protein Ligases , Animals , Apoptosis/drug effects , Ubiquitin-Protein Ligases/metabolism , Phenols/pharmacology , Phenols/chemistry , Glucosides/pharmacology , Glucosides/chemistry , Mice , Protein Kinases/metabolism , Mitophagy/drug effects , Mitochondria/drug effects , Mitochondria/metabolism , Reactive Oxygen Species/metabolism , Membrane Potential, Mitochondrial/drug effects , Cell Line , Cell Survival/drug effects
2.
Front Vet Sci ; 10: 1319857, 2023.
Article in English | MEDLINE | ID: mdl-38033639

ABSTRACT

The toxic heavy metal cadmium (Cd) has a significant impact on kidney health. Documents manifested that non-toxic flavonoid quercetin can reduce Cd-induced kidney damage by reducing oxidative stress and inhibiting apoptosis, while the effect of quercetin on Cd-induced renal cell pyroptosis has not been elucidated. In this study, we established a model of Cd poisoning treated with quercetin both in vitro and in vivo. Results revealed that quercetin effectively reversed the decrease in Cd-induced cell viability. Furthermore, Cd increased blood urea nitrogen while reducing GPX and SOD levels, caused histopathological injuries in kidney with a significantly elevated cell pyroptosis characterized by enhanced levels of proteins representing assembly (NLRP3) and activation (pro IL-1ß, cleaved IL-1ß, and IL-18) of NLRP3 inflammasome as well as pyroptosis executor (pro caspase-1, cleaved caspase-1). However, quercetin administration alleviated kidney injuries above by decreasing cell pyroptosis. Overall, it suggests that kidney cells are susceptible to pyroptotic cell death due to Cd exposure; while quercetin exhibits protective effects through cell pyroptosis inhibition.

3.
J Dairy Res ; 90(2): 158-163, 2023 May.
Article in English | MEDLINE | ID: mdl-37381099

ABSTRACT

To contribute to the treatment decision and optimize coagulase-negative staphylococcus (CNS) control programs, we conducted a meta-analysis to investigate the epidemiology and antimicrobial resistance rates of coagulase-negative staphylococcus associated with bovine mastitis in China. Three databases (PubMed, Google scholar and China National Knowledge Infrastructure database) were utilized to obtain relevant publications. A total of 18 publications were included in our research, and 3 of them included antimicrobial resistant (AMR) test. The pooled prevalence of coagulase-negative staphylococcus was 17.28%. Subgroup analysis revealed that the prevalence was higher in South China than in North China, was higher in 2011-2020 than in 2000-2010 and was higher in clinical bovine mastitis cases than in subclinical cases. The pooled AMR were most resistant to ß-lactams, followed by tetracyclines, quinolones, nitrofurans, lincosamides, sulfonamides, amphenicol and aminoglycosides. The pooled AMR rate of coagulase-negative staphylococcus was lower in 2011-2020 than in 2000-2010. Although the prevalence of CNS showed an increasing trend over 20 years, the AMR rate showed a decreasing trend, and the clinical type of mastitis was the most frequent and the prevalence was highest in South China. Finally, CNS was most resistant to ß-lactams amongst the eight groups of antimicrobial agents.


Subject(s)
Cattle Diseases , Mastitis, Bovine , Staphylococcal Infections , Cattle , Female , Animals , Anti-Bacterial Agents/pharmacology , Coagulase , Staphylococcal Infections/epidemiology , Staphylococcal Infections/veterinary , Mastitis, Bovine/drug therapy , Mastitis, Bovine/epidemiology , Prevalence , Drug Resistance, Bacterial , Staphylococcus , beta-Lactams , Microbial Sensitivity Tests/veterinary
4.
Front Vet Sci ; 9: 1006676, 2022.
Article in English | MEDLINE | ID: mdl-36439336

ABSTRACT

In this study, to optimize the Staphylococcus aureus control program, a meta-analysis was conducted to investigate the epidemiology and antimicrobial resistance (AMR) profile of S. aureus-associated bovine mastitis in China from 2000 to 2020. A total of 33 publications from PubMed, Google Scholar, and China National Knowledge Infrastructure (CNKI) database were included in our research, among which nine publications included the AMR test. The pooled prevalence of S. aureus was 36.23%, and subgroup analysis revealed that the prevalence dropped from 2000-2010 to 2011-2020, which shows that China is on the right track. The pooled AMR rate indicate isolates were most resistant to ß-lactams (50.68%), followed by quinolones (36.23%), macrolides (34.08%), sulfonamides (32.25%), tetracyclines (27.83%), aminoglycosides (26.44%), lincosamides (23.39%), and amphenicol (10.33%). Both the pooled prevalence and AMR of S. aureus in China are higher than those in Western countries, such as Germany, Belgium, Ireland, and the United States-countries with a long animal husbandry history and good management. Thus, there is still room to improve the treatment of S. aureus-associated bovine mastitis in China.

5.
BMC Health Serv Res ; 22(1): 287, 2022 Mar 03.
Article in English | MEDLINE | ID: mdl-35236341

ABSTRACT

BACKGROUND: The smart hospital's concept of using the Internet of Things (IoT) to reduce human resources demand has become more popular in the aging society. OBJECTIVE: To implement the voice smart care (VSC) system in hospital wards and explore patient acceptance via the Technology Acceptance Model (TAM). METHODS: A structured questionnaire based on TAM was developed and validated as a research tool. Only the patients hospitalized in the VSC wards and who used it for more than two days were invited to fill the questionnaire. Statistical variables were analyzed using SPSS version 24.0. A total of 30 valid questionnaires were finally obtained after excluding two incomplete questionnaires. Cronbach's α values for all study constructs were above 0.84. RESULT: We observed that perceived ease of use on perceived usefulness, perceived usefulness on user satisfaction and attitude toward using, and attitude toward using on behavioral intention to use had statistical significance (p < .01), respectively. CONCLUSION: We have successfully developed the VSC system in a Taiwanese academic medical center. Our study indicated that perceived usefulness was a crucial factor, which means the system function should precisely meet the patients' demands. Additionally, a clever system design is important since perceived ease of use positively affects perceived usefulness. The insight generated from this study could be beneficial to hospitals when implementing similar systems to their wards.


Subject(s)
Aging , Intention , Attitude , Hospitals , Humans , Pilot Projects
6.
Neuroscience ; 481: 123-133, 2022 01 15.
Article in English | MEDLINE | ID: mdl-34875363

ABSTRACT

Cortical reorganization occurs immediately after peripheral nerve injury, and early sensorimotor training is suggested during nerve regeneration. The effect of mirror therapy and classical sensory relearning on cortical activation immediately after peripheral nerve repair of the forearm is unknown. Six participants were randomly assigned to the mirror-therapy group or the sensory-relearning group. Sensorimotor training was conducted in a mirror box for 12 weeks. The mirror-therapy group used mirror reflection of the unaffected hand in order to train the affected hand, and the sensory-relearning group trained without mirror reflection. Semmes-Weinstein Monofilaments (SWM) test, static 2-point discrimination test (S-2PD), grip strength, and the Disabilities of the Arm, Shoulder and Hand (DASH) scores were measured at baseline, the end of the intervention (T1), and 3 months after the intervention (T2). Finger and manual dexterity were measured at T1 and T2, and a functional MRI (fMRI) was conducted at T1. All participants showed improvement in the SWM, S-2PD tests, upper extremity function, and grip strength after the intervention at T1, except for the participant who injured both the median and ulnar nerves in the sensory-relearning group. In addition, the mirror-therapy group had better outcomes in finger dexterity and manual dexterity, and fMRIs showed greater activation in the multimodal association cortices and ipsilateral brain areas during motor tasks. This study provides evidence-based results confirming the benefits of early sensorimotor relearning for cortical activation in peripheral nerve injury of the forearm and different neuroplasticity patterns between mirror therapy and classical sensor relearning.


Subject(s)
Forearm , Mirror Movement Therapy , Fingers , Humans , Motor Skills , Ulnar Nerve
7.
Cancer Genomics Proteomics ; 15(6): 453-460, 2018.
Article in English | MEDLINE | ID: mdl-30343279

ABSTRACT

AIM: Arsenic trioxide (As2O3), known as pi-shuang and the most toxic compound in traditional Chinese medicine, has been used as an antitumor agent for thousands of years. Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural phenol that has significant anti-bacterial, anti-fungaI and antiaging activities. Our study aimed to examine the combined anticancer effects of As2O3 and resveratrol against human neuroblastoma SK-N-SH cells, and elucidate the underlying intracellular signaling. MATERIALS AND METHODS: SK-N-SH cells were treated with an extremely low-dose (2-4 µM) of As2O3 alone or combined with 75 µg/ml resveratrol for further comparisons. Cell viability, apoptotic signaling as well as synergistic cytotoxic effects were estimated using the MTT assay, microscopy observation, flow cytometric analysis for loss of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS), and typical quantitative western blotting analysis. Student's t-test, and one- and two-way analysis of variance (ANOVA) were used for examination of significant differences. RESULTS: The combined treatment was more effective than single treatment of As2O3 or resveratrol alone in suppressing cell viability, which correlated with the elevation of ROS levels. The intracellular mechanisms of cytotoxicity of As2O3 plus resveratrol were revealed as ROS accumulation and relative decrease of MMP, leading to activation of caspase-3 and -9, but not of caspase-1, -7 and-8. Combination treatment reduced the expression of B-cell lymphoma 2 (BCL2), BH3 interacting domain death agonist (BID), and BCL-x/L. CONCLUSION: Combined treatment at extremely low concentration of two agents from natural products, As2O3 and resveratrol, has high potential as a cocktail of anticancer drugs for neuroblastoma.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Apoptosis/drug effects , Neoplasm Proteins/metabolism , Neuroblastoma/drug therapy , Neuroblastoma/metabolism , Arsenic Trioxide/pharmacology , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Neuroblastoma/pathology , Resveratrol/pharmacology
8.
Methods Mol Biol ; 1593: 229-242, 2017.
Article in English | MEDLINE | ID: mdl-28389958

ABSTRACT

The bacterial flagellar motor is a large multi-component molecular machine. Structural determination of such a large complex is often challenging and requires extensive structural analysis in situ. Cryo-electron tomography (cryo-ET) has emerged as a powerful technique that enables us to visualize intact flagellar motors in cells with unprecedented details. Here, we detail the procedure beginning with sample preparation, followed by data acquisition, tomographic reconstruction, sub-tomogram analysis, and ultimately visualization of the intact spirochetal flagellar motor in Borrelia burgdorferi. The procedure is applicable to visualize other molecular machinery in bacteria or other organisms.


Subject(s)
Bacterial Proteins/metabolism , Molecular Motor Proteins/metabolism , Borrelia burgdorferi/metabolism , Cryoelectron Microscopy/methods , Electron Microscope Tomography/methods , Flagella/metabolism
9.
Mol Microbiol ; 103(1): 67-85, 2017 01.
Article in English | MEDLINE | ID: mdl-27696564

ABSTRACT

While protein glycosylation has been reported in several spirochetes including the syphilis bacterium Treponema pallidum and Lyme disease pathogen Borrelia burgdorferi, the pertinent glycan structures and their roles remain uncharacterized. Herein, a novel glycan with an unusual chemical composition and structure in the oral spirochete Treponema denticola, a keystone pathogen of periodontitis was reported. The identified glycan of mass 450.2 Da is composed of a monoacetylated nonulosonic acid (Non) with a novel extended N7 acyl modification, a 2-methoxy-4,5,6-trihydroxy-hexanoyl residue in which the Non has a pseudaminic acid configuration (L-glycero-L-manno) and is ß-linked to serine or threonine residues. This novel glycan modifies the flagellin proteins (FlaBs) of T. denticola by O-linkage at multiple sites near the D1 domain, a highly conserved region of bacterial flagellins that interact with Toll-like receptor 5. Furthermore, mutagenesis studies demonstrate that the glycosylation plays an essential role in the flagellar assembly and motility of T. denticola. To our knowledge, this novel glycan and its unique modification sites have not been reported previously in any bacteria.


Subject(s)
Polysaccharides/chemistry , Polysaccharides/metabolism , Treponema denticola/metabolism , Amino Acid Sequence , Bacterial Proteins/metabolism , Flagella/genetics , Flagella/metabolism , Flagellin/metabolism , Glycosylation , Structure-Activity Relationship , Treponema denticola/genetics
10.
Mol Microbiol ; 102(2): 336-348, 2016 10.
Article in English | MEDLINE | ID: mdl-27416872

ABSTRACT

Borrelia burgdorferi, the causative agent of Lyme disease, is a highly motile spirochete, and motility, which is provided by its periplasmic flagella, is critical for every part of the spirochete's enzootic life cycle. Unlike externally flagellated bacteria, spirochetes possess a unique periplasmic flagellar structure called the collar. This spirochete-specific novel component is linked to the flagellar basal body; however, nothing is known about the proteins encoding the collar or their function in any spirochete. To identify a collar protein and determine its function, we employed a comprehensive strategy that included genetic, biochemical, and microscopic analyses. We found that BB0286 (FlbB) is a novel flagellar motor protein, which is located around the flagellar basal body. Deletion of bb0286 has a profound effect on collar formation, assembly of other flagellar structures, morphology, and motility of the spirochete. Orientation of the flagella toward the cell body is critical for determination of wild-type spirochete's wave-like morphology and motility. Here, we provide the first evidence that FlbB is a key determinant of normal orientation of the flagella and collar assembly.


Subject(s)
Borrelia burgdorferi/cytology , Borrelia burgdorferi/metabolism , Flagella/metabolism , Bacterial Proteins/metabolism , Borrelia burgdorferi/genetics , Flagella/genetics , Molecular Motor Proteins/genetics , Molecular Motor Proteins/metabolism , Periplasm/metabolism , Spirochaetales/genetics , Spirochaetales/metabolism , Trans-Activators/genetics , Trans-Activators/metabolism
11.
Methods Mol Biol ; 1328: 151-62, 2015.
Article in English | MEDLINE | ID: mdl-26324436

ABSTRACT

The Drosophila melanogaster ovary is a powerful, genetically tractable system through which one can elucidate the principles underlying cellular function and organogenesis in vivo. In order to understand the intricate process of oogenesis at the subcellular level, microscopic analysis with the highest possible resolution is required. In this chapter, we describe the preparation of ovaries for ultrastructural analysis using transmission electron microscopy and focused ion beam scanning electron microscopy. We discuss and provide protocols for chemical fixation of Drosophila ovaries that facilitate optimal imaging with particular attention paid to preserving and resolving mitochondrial membrane morphology and structure.


Subject(s)
Microscopy, Electron, Transmission/methods , Oogenesis , Ovary/ultrastructure , Animals , Drosophila melanogaster , Female
12.
Anticancer Res ; 35(9): 4691-6, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26254358

ABSTRACT

AIM: The present study aimed at investigating whether X-ray repair cross complementing protein 3 (XRCC3) genotype may serve as a useful marker for detecting leiomyoma and predicting risk. MATERIALS AND METHODS: A total of 640 women (166 patients with leiomyoma and 474 healthy controls) were examined for their XRCC3 rs1799794, rs45603942, rs861530, rs3212057, rs1799796, rs861539, rs28903081 genotype. The distributions of genotypic and allelic frequencies between the two groups were compared. RESULTS: The results showed that the CT and TT genotypes of XRCC3 rs861539 were associated with increased leiomyoma risk (odds ratio=2.19, 95% confidence interval=1.23-3.90; odds ratio=3.72, 95% confidence interval=1.23-11.26, respectively). On allelic frequency analysis, we found a significant difference in the distribution of the T allelic frequency of the XRCC3 rs861539 (p=5.88 × 10(-5)). None of the other six single nucleotide polymorphisms were associated with altered leiomyoma susceptibility. CONCLUSION: The T allele (CT and TT genotypes) of XRCC3 rs861539 contributes to increased risk of leiomyoma among Taiwanese women and may serve as a early detection and predictive marker.


Subject(s)
DNA-Binding Proteins/genetics , Genetic Predisposition to Disease , Leiomyoma/genetics , Adult , Alleles , Case-Control Studies , Demography , Female , Humans , Middle Aged , Polymorphism, Single Nucleotide/genetics , Risk Factors , Uterine Neoplasms/genetics
13.
Anticancer Res ; 35(9): 4975-81, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26254397

ABSTRACT

AIM: It has been proposed that genetic variations of DNA repair genes confer susceptibility to cancer, and the DNA repair gene xeroderma pigmentosum group D (XPD), the caretaker of genome stability, is thought to play a major role in the nucleotide excision repair system. We investigated three genotypes of XPD, at promoter -114 (rs3810366), and codon 312 (rs1799793), 751 (rs13181), and their associated with gastric cancer susceptibility in a Taiwanese population. MATERIALS AND METHODS: In the present study, 121 patients with gastric cancer and 363 gender- and age-matched healthy controls were recruited and genotyped for XPD by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) methodology, and the association of XPD genotype with gastric cancer risk was investigated. RESULTS: We found a significant difference in the distribution of A allele-bearing XPD codon 312 genotypes [odds ratio (OR)=1.64, 95% confidence interval (CI)=1.20-2.25, p=0.0019], but not in XPD codon 751 or promoter -114 sites, between the gastric cancer and control groups. Those who had G/A or A/A at XPD codon 312 had a 1.83-fold (95% CI=1.14-2.95, p=0.0159) and 1.87-fold (95% CI=1.04-3.34, p=0.0378) increased risk of gastric cancer compared to those with G/G. The risk for G/A and A/A genotypes had synergistic effects with alcohol drinking (OR=11.27, 95% CI=3.72-34.17, p=0.0001), cigarette smoking (OR=23.20, 95% CI=6.24-86.23, p=0.0001) and Helicobacter pylori infection (OR=5.38, 95% CI=2.76-10.52, p=0.0001) on gastric cancer susceptibility. CONCLUSION: Our findings suggest that the A allele of XPD codon 312 may contribute to gastric carcinogenesis and may be useful for early detection and prevention of gastric cancer.


Subject(s)
Genetic Predisposition to Disease , Stomach Neoplasms/genetics , Xeroderma Pigmentosum/genetics , Alcohol Drinking/genetics , Case-Control Studies , Female , Gene Frequency/genetics , Helicobacter Infections/complications , Humans , Male , Middle Aged , Polymorphism, Genetic , Risk Factors , Taiwan , Xeroderma Pigmentosum/complications
14.
Cancer Genomics Proteomics ; 11(6): 295-301, 2014.
Article in English | MEDLINE | ID: mdl-25422360

ABSTRACT

BACKGROUND/AIM: The altered cellular repair capacity plays a critical role in genomic instability and carcinogenesis. We aimed at evaluating the contribution of the polymorphic variant in apurinic/apyriminidinic endonuclease (APEX1) gene to its mRNA and protein levels and the risk of endometriosis. PATIENTS AND METHODS: In the current case-control study, 153 endometriosis patients and 636 non-endometriosis controls were recruited. APEX1 Asp(148)Glu (rs1130409) genotyping was conducted by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). At the same time, twenty eight endometriosis tissue samples with different genotypes were examined regarding their expression levels of APEX1 mRNA and protein by quantitative reverse transcription-polymerase chain reaction (q-PCR) and western blotting, respectively. RESULTS: Compared with wild-type TT genotype, TG and GG genotypes of APEX1 Asp(148)Glu had a risk of endometriosis of 0.93- and 0.87-fold. The results from in vivo transcriptional (RNA) and translational (protein) level analysis revealed that the APEX1 mRNA and protein were of similar levels among the endometriosis tissues of people carrying TT, TG, or GG genotypes. There was no joint effect of APEX1 Asp(148)Glu genotype with menarche, pregnancy, smoking or alcohol drinking lifestyles on endometriosis risk. CONCLUSION: The APEX1 Asp(148)Glu genotype correlates well with its mRNA and protein expression among endometriosis patients and may not serve as a sensitive marker for prediction of endometriosis risk in Taiwan.


Subject(s)
DNA Repair/genetics , DNA-(Apurinic or Apyrimidinic Site) Lyase/genetics , Endometriosis/enzymology , Endometriosis/genetics , Genetic Predisposition to Disease , Adult , Alcohol Drinking/adverse effects , Amino Acid Substitution , Case-Control Studies , Female , Gene Expression Regulation , Humans , Menarche/genetics , Pregnancy , RNA, Messenger/genetics , RNA, Messenger/metabolism , Risk Factors , Smoking/adverse effects
15.
Genes Dev ; 24(17): 1876-81, 2010 Sep 01.
Article in English | MEDLINE | ID: mdl-20713507

ABSTRACT

Piwi proteins are modified by symmetric dimethylation of arginine (sDMA), and the methylarginine-dependent interaction with Tudor domain proteins is critical for their functions in germline development. Cocrystal structures of an extended Tudor domain (eTud) of Drosophila Tudor with methylated peptides of Aubergine, a Piwi family protein, reveal that sDMA is recognized by an asparagine-gated aromatic cage. Furthermore, the unexpected Tudor-SN/p100 fold of eTud is important for sensing the position of sDMA. The structural information provides mechanistic insights into sDMA-dependent Piwi-Tudor interaction, and the recognition of sDMA by Tudor domains in general.


Subject(s)
Arginine/analogs & derivatives , Drosophila Proteins/chemistry , Drosophila Proteins/metabolism , Drosophila melanogaster/metabolism , Membrane Transport Proteins/chemistry , Membrane Transport Proteins/metabolism , Models, Molecular , Peptide Initiation Factors/chemistry , Peptide Initiation Factors/metabolism , Amino Acid Sequence , Animals , Arginine/chemistry , Arginine/metabolism , Conserved Sequence , Drosophila melanogaster/chemistry , Drosophila melanogaster/genetics , Germ Cells/growth & development , Germ Cells/metabolism , Molecular Sequence Data , Protein Binding , Protein Structure, Quaternary , Protein Structure, Tertiary , Sequence Alignment
16.
Chin J Physiol ; 50(3): 127-34, 2007 Jun 30.
Article in English | MEDLINE | ID: mdl-17867433

ABSTRACT

Hypoxia/reoxygenation (H/R) elicits neuronal cell injury and glial cell activation within the central nervous system (CNS). Neuroinflammation is a process that primarily results from the acute or chronic activation of glial cells. This overactive state of glial cells results in the increased release of nitric oxide (NO) and/or tumor necrosis factor alpha (TNF-alpha), a process which can lead to neuronal damage or death. In this study, we found that hypoxia for eight or twelve hours (h) followed by 24 h reoxygenation (H8/ R24 or H12/R24) induced NO production and TNF-alpha release from cultures of enriched microglial or mixed glial cells. However, microglial cells could not survive longer periods of hypoxia (> or = 12 h) in microglia-enriched culture. While astrocytes retained a 95% viability following longer periods of H/R in astrocyte-enriched cultures, they did not produce any significant quantities of NO and TNF-alpha. Reoxygenation for prolonged periods (three and five days) following H24 resulted in progressively greater increases in NO production (about two-fold greater level in hypoxia as compared to normoxic conditions) accompanied by relatively less increases in TNF-alpha release in mixed glial cell cultures. Our data indicate that inflammatory mediators such as NO and TNF-alpha are released from glia-enriched mix culture in response to H/R. While microglial cells are more vulnerable than astrocytes during H/R, they survive longer in the presence of astrocyte and are the major cell type producing NO and TNF-alpha. Furthermore, the TNF-alpha release precedes NO production in response to a prolonged duration of reoxygenation following hypoxia for 24 h.


Subject(s)
Astrocytes/metabolism , Cell Hypoxia , Microglia/metabolism , Nitric Oxide/metabolism , Oxygen/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Astrocytes/cytology , Cell Survival , Cells, Cultured , Microglia/cytology , Rats , Time Factors
17.
Int J Radiat Oncol Biol Phys ; 68(5): 1342-8, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17449194

ABSTRACT

PURPOSE: To evaluate the long-term prognostic impact of plasma Epstein-Barr virus (EBV) DNA concentration measured by real-time quantitative polymerase chain reaction (RTQ-PCR) in nasopharyngeal carcinoma (NPC) patients receiving concurrent chemoradiotherapy (CCRT). METHODS AND MATERIALS: Epstein-Barr virus DNA was retrospectively measured from stock plasma of 152 biopsy-proven NPC patients with Stage II-IV (M0) disease with a RTQ-PCR using the minor groove binder-probe. All patients received CCRT with a median follow-up of 78 months. We divided patients into three subgroups: (1) low pretreatment EBV DNA (<1,500 copies/mL) and undetectable posttreatment EBV DNA (pre-L/post-U), (2) high pretreatment EBV DNA (> or =1,500 copies/mL) and undetectable posttreatment EBV DNA (pre-H/post-U), and (3) low or high pretreatment EBV DNA and detectable posttreatment EBV DNA (pre-L or H/post-D) for prognostic analyses. RESULTS: Epstein-Barr virus DNA (median concentration, 573 copies/mL; interquartile range, 197-3,074) was detected in the pretreatment plasma of 94.1% (143/152) of patients. After treatment, plasma EBV DNA decreased or remained 0 for all patients and was detectable in 31 patients (20.4%) with a median concentration 0 copy/mL (interquartile range, 0-0). The 5-year overall survival rates of the pre-L/post-U, pre-H/post-U, and pre-L or H/post-D subgroups were 87.2%, 71.0%, and 38.7%, respectively (p < 0.0001). The relapse-free survival showed similar results with corresponding rates of 85.6%, 75.9%, and 26.9%, respectively (p < 0.0001). Multivariate Cox analysis confirmed the superior effects of plasma EBV DNA compared to other clinical parameters in prognosis prediction. CONCLUSION: Plasma EBV DNA is the most valuable prognostic factor for NPC. More chemotherapy should be considered for patients with persistently detectable EBV DNA after CCRT.


Subject(s)
DNA, Viral/blood , Herpesvirus 4, Human/genetics , Nasopharyngeal Neoplasms/virology , Adult , Aged , Aged, 80 and over , Combined Modality Therapy/methods , Disease-Free Survival , Female , Humans , Male , Middle Aged , Nasopharyngeal Neoplasms/blood , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/radiotherapy , Polymerase Chain Reaction/methods , Prognosis , Retrospective Studies
18.
Development ; 133(20): 4053-62, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16971472

ABSTRACT

Tudor domains are found in many organisms and have been implicated in protein-protein interactions in which methylated protein substrates bind to these domains. Here, we present evidence for the involvement of specific Tudor domains in germline development. Drosophila Tudor, the founder of the Tudor domain family, contains 11 Tudor domains and is a component of polar granules and nuage, electron-dense organelles characteristic of the germline in many organisms, including mammals. In this study, we investigated whether the 11 Tudor domains fulfil specific functions for polar granule assembly, germ cell formation and abdomen formation. We find that even a small number of non-overlapping Tudor domains or a substantial reduction in overall Tudor protein is sufficient for abdomen development. In stark contrast, we find a requirement for specific Tudor domains in germ cell formation, Tudor localization and polar granule architecture. Combining genetic analysis with structural modeling of specific Tudor domains, we propose that these domains serve as ;docking platforms' for polar granule assembly.


Subject(s)
Cytoplasmic Granules/ultrastructure , Drosophila Proteins/physiology , Drosophila/embryology , Membrane Transport Proteins/physiology , Oocytes/growth & development , Abdomen/growth & development , Animals , Body Patterning , Drosophila/chemistry , Drosophila Proteins/analysis , Drosophila Proteins/genetics , Embryo, Nonmammalian/chemistry , Embryo, Nonmammalian/metabolism , Female , Germ Cells/growth & development , Membrane Transport Proteins/analysis , Membrane Transport Proteins/genetics , Mutation, Missense , Oocytes/chemistry , Oocytes/ultrastructure , Protein Structure, Tertiary/genetics , Protein Structure, Tertiary/physiology
19.
Neurosci Lett ; 322(3): 187-91, 2002 Apr 12.
Article in English | MEDLINE | ID: mdl-11897169

ABSTRACT

Hypoxia/reoxygenation (H/R) causes cell injury/death. We examined the protection by drugs intervening at various stages of the injury cascade in cultured neurons and glia. Primary cultures of rat cortical neurons and mixed glia were subjected to H/R. Measurements of cell death (by lactate dehydrogenase release into the medium) and viability (by MTT reduction) indicated that H/R led to time-dependent injury in both neuronal and mixed glial cultures. The extent of cell injury in neurons was significantly greater than in glia cells. Pretreatment with (+)-MK-801 hydrogen maleate (MK-801) (an N-methyl-D-aspartate antagonist), N(omega)-nitro-L-arginine methyl ester (L-NAME) (an inhibitor of nitric oxide synthase) or free radical scavengers reduced the extent of the H/R-elicited neuronal damage. MK-801, in contrast, was without effect on glial cells while L-NAME was effective. Our results suggest differential mechanism(s) and susceptibility to injury caused by H/R for neurons and mixed glia.


Subject(s)
Hypoxia-Ischemia, Brain/pathology , Neuroglia/pathology , Neurons/pathology , Reperfusion Injury/pathology , Animals , Antioxidants/pharmacology , Astrocytes/pathology , Cell Death/drug effects , Cells, Cultured , Dizocilpine Maleate/pharmacology , Enzyme Inhibitors/pharmacology , Excitatory Amino Acid Antagonists/pharmacology , Female , Free Radicals/toxicity , L-Lactate Dehydrogenase/metabolism , NG-Nitroarginine Methyl Ester/pharmacology , Neuroprotective Agents/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase Type I , Pregnancy , Rats , Rats, Sprague-Dawley , Tetrazolium Salts , Thiazoles
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