410 research outputs found
Fibronectin-Containing Extracellular Vesicles Protect Melanocytes against Ultraviolet Radiation-Induced Cytotoxicity.
Skin melanocytes are activated by exposure to UV radiation to secrete melanin-containing melanosomes to protect the skin from UV-induced damage. Despite the continuous renewal of the epidermis, the turnover rate of melanocytes is very slow, and they survive for long periods. However, the mechanisms underlying the survival of melanocytes exposed to UV radiation are not known. Here, we investigated the role of melanocyte-derived extracellular vesicles in melanocyte survival. Network analysis of the melanocyte extracellular vesicle proteome identified the extracellular matrix component fibronectin at a central node, and the release of fibronectin-containing extracellular vesicles was increased after exposure of melanocytes to UVB radiation. Using an anti-fibronectin neutralizing antibody and specific inhibitors of extracellular vesicle secretion, we demonstrated that extracellular vesicles enriched in fibronectin were involved in melanocyte survival after UVB radiation. Furthermore, we observed that in the hyperpigmented lesions of patients with melasma, the extracellular space around melanocytes contained more fibronectin compared with normal skin, suggesting that fibronectin is involved in maintaining melanocytes in pathological conditions. Collectively, our findings suggest that melanocytes secrete fibronectin-containing extracellular vesicles to increase their survival after UVB radiation. These data provide important insight into how constantly stimulated melanocytes can be maintained in pathological conditions such as melasma.1166Ysciescopu
Media Representations of Breech Birth: A Prospective Analysis of Web-Based News Reports
© 2017 by the American College of Nurse-Midwives Introduction: Recent research has demonstrated that the media presentation of childbirth is highly medicalized, often portraying birth as risky and dramatic. Media representation of breech presentation and birth is unexplored in this context. This study aimed to explore the content and tone of news media reports relating to breech presentation and breech birth. Methods: Google alerts were created using the terms breech and breech birth in online English-language news sites over a 3-year period from January 1, 2013, to December 31, 2015. Alerts were received daily and filed for analysis, and data were analyzed to generate themes. Results: A total of 138 web-based news reports were gathered from 9 countries. Five themes that arose from the data included the problem of breech presentation, the high drama of vaginal breech birth, the safe option of cesarean birth versus dangers of vaginal breech birth, the defiant mother versus the saintly mother, and vaginal breech birth and medical misadventure. Discussion: Media reports in this study predominantly demonstrated negative views toward breech presentation and vaginal breech birth. Cesarean birth was portrayed as the safe option for breech birth, while vaginal breech birth was associated with poor outcomes. Media presentations may impact decision making about mode of birth for pregnant women with a breech fetus. Health care providers can play an important role in balancing the media depiction of planned vaginal breech birth by providing nonjudgmental, evidence-based information to such women to facilitate informed decision making for birth
Classification of gluteal muscle contracture in children and outcome of different treatments
<p>Abstract</p> <p>Background</p> <p>Gluteal muscle contracture (GMC) is a clinical syndrome due to multiple etiologies in which hip movements may be severely limited. The aim of this study was to propose a detailed classification of GMC and evaluate the statistical association between outcomes of different management and patient conditions.</p> <p>Methods</p> <p>One hundred fifty-eight patients, who were treated between January 1995 and December 2004, were reviewed at a mean duration of follow-up of 4.8 years. Statistical analyses were performed using X<sup>2 </sup>and Fisher's exact tests.</p> <p>Results</p> <p>Non-operative management (NOM), as a primary treatment, was effective in 19 of 49 patients (38.8%), while operative management was effective in all 129 patients, with an excellence rating of 83.7% (108/129). The outcome of NOM in level I patients was significantly higher than in level II and III patients (<it>P </it>< 0.05). The results of NOM and operative management in the child group were better than the adolescent group (<it>P </it>< 0.05). Complications in level III were more than in level II.</p> <p>Conclusion</p> <p>NOM was more effective in level I patients than in level II and III patients. Operative management was effective in patients at all levels, with no statistical differences between levels or types. We recommend NOM as primary treatment for level I patients and operative management for level II and III patients. Either NOM or operative management should be carried out as early as possible.</p
Schistosomiasis Research in the Dongting Lake Region and Its Impact on Local and National Treatment and Control in China
Schistosomiasis is a chronic and debilitating parasitic disease that has often been neglected because it is a disease of poverty, affecting poor rural communities in the developing world. This is not the case in the People's Republic of China (PRC), where the disease, caused by Schistosoma japonicum, has long captured the attention of the Chinese authorities who have, over the past 50–60 years, undertaken remarkably successful control programs that have substantially reduced the schistosomiasis disease burden. The Dongting Lake region in Hunan province is one of the major schistosome-endemic areas in the PRC due to its vast marshland habitats for the Oncomelania snail intermediate hosts of S. japonicum. Along with social, demographic, and other environmental factors, the recent completion and closure of the Three Gorges dam will most likely increase the range of these snail habitats, with the potential for re-emergence of schistosomiasis and increased transmission in Hunan and other schistosome-endemic provinces being a particular concern. In this paper, we review the history and the current status of schistosomiasis control in the Dongting Lake region. We explore the epidemiological factors contributing to S. japonicum transmission there, and summarise some of the key research findings from studies undertaken on schistosomiasis in Hunan province over the past 10 years. The impact of this research on current and future approaches for sustainable integrated control of schistosomiasis in this and other endemic areas in the PRC is emphasised
The eggshell membrane : A potential biomaterial for corneal wound healing
The eggshell membrane (ESM) is an abundant resource with innate complex structure and composition provided by nature. With at least 60 million tonnes of hen eggs produced globally per annum, utilisation of this waste resource is highly attractive in positively impacting sustainability worldwide. Given the morphology and mechanical properties of this membrane, it has great potential as a biomaterials for wound dressing. However, to date, no studies have demonstrated nor reported this application. As such, the objective of this investigation was to identify and optimise a reproducible extraction protocol of the ESM and to assess the physical, chemical, mechanical and biological properties of the substrate with a view to use as a wound dressing. ESM samples were isolated by either manual peeling (ESM-strip) or via extraction using acetic acid [ESM-A0.5] or ethylenediaminetetraacetic acid, EDTA [ESM-E0.9]. Energy dispersive X-ray spectroscopy (EDS) confirmed that there were no traces of calcium residues from the extraction process. Fourier transform infrared (FTIR) spectroscopy revealed that the extraction method (acetic acid and EDTA) did not alter the chemical structures of the ESM and also clarified the composition of the fibrous proteins of the ESM. Scanning electron microscopy (SEM) analyses revealed a three-layer composite structure of the ESM: an inner layer as continuous, dense and non-fibrous (limiting membrane), a middle layer with a network of fibres (inner shell membrane) and the outer layer (outer shell membrane) of larger fibres. Material properties including optical transparency, porosity, fluid absorption/uptake, thermal stability, mechanical profiling of the ESM samples were performed and demonstrated suitable profiles for translational applications. Biological in vitro studies using SV40 immortalised corneal epithelial cells (ihCEC) and corneal mesenchymal stromal cells (C-MSC) demonstrated excellent biocompatibility. Taken together, these results document the development of a novel sustainable biomaterial that may be used for ophthalmic wounds and/or other biomedical therapies.Peer reviewe
Effective Interventions and Decline of Antituberculosis Drug Resistance in Eastern Taiwan, 2004–2008
BACKGROUND: The Taiwan health authority recently launched several tuberculosis (TB) control interventions, which may have an impact on the epidemic of drug-resistant TB. We conducted a population-based antituberculosis drug resistance surveillance program in Eastern Taiwan to measure the proportions of notified TB patients with anti-TB drug resistance and the trend from 2004 to 2008. METHODS AND FINDINGS: All culture-positive TB patients were enrolled. Drug susceptibility testing results of the first isolate of each TB patient in each treatment course were analyzed. In total, 2688 patients were included, of which 2176 (81.0%) were new TB cases and 512 (19.0%) were previously treated cases. Among the 2176 new TB cases, 97 (4.5%) were retreated after the first episode of TB treatment within the study period. The proportion of new patients with any resistance, isoniazid resistance but not multidrug-resistant TB (resistant to at least isoniazid and rifampin, MDR-TB), and MDR-TB was 16.4%, 7.5%, and 4.0%, respectively, and that among previously treated cases was 30.9%, 7.9%, and 17.6%, respectively. The combined proportion of any resistance decreased from 23.3% in 2004 to 14.3% in 2008, and that of MDR-TB from 11.5% to 2.4%. CONCLUSIONS: The proportion of TB patients with drug-resistant TB in Eastern Taiwan remains substantial. However, an effective TB control program has successfully driven the proportion of drug resistance among TB patients downward
Microparticle-mediated transfer of the viral receptors CAR and CD46, and the CFTR channel in a CHO cell model confers new functions to target cells
Cell microparticles (MPs) released in the extracellular milieu can embark plasma membrane and intracellular components which are specific of their cellular origin, and transfer them to target cells. The MP-mediated, cell-to-cell transfer of three human membrane glycoproteins of different degrees of complexity was investigated in the present study, using a CHO cell model system. We first tested the delivery of CAR and CD46, two monospanins which act as adenovirus receptors, to target CHO cells. CHO cells lack CAR and CD46, high affinity receptors for human adenovirus serotype 5 (HAdV5), and serotype 35 (HAdV35), respectively. We found that MPs derived from CHO cells (MP-donor cells) constitutively expressing CAR (MP-CAR) or CD46 (MP-CD46) were able to transfer CAR and CD46 to target CHO cells, and conferred selective permissiveness to HAdV5 and HAdV35. In addition, target CHO cells incubated with MP-CD46 acquired the CD46-associated function in complement regulation. We also explored the MP-mediated delivery of a dodecaspanin membrane glycoprotein, the CFTR to target CHO cells. CFTR functions as a chloride channel in human cells and is implicated in the genetic disease cystic fibrosis. Target CHO cells incubated with MPs produced by CHO cells constitutively expressing GFP-tagged CFTR (MP-GFP-CFTR) were found to gain a new cellular function, the chloride channel activity associated to CFTR. Time-course analysis of the appearance of GFP-CFTR in target cells suggested that MPs could achieve the delivery of CFTR to target cells via two mechanisms: the transfer of mature, membrane-inserted CFTR glycoprotein, and the transfer of CFTR-encoding mRNA. These results confirmed that cell-derived MPs represent a new class of promising therapeutic vehicles for the delivery of bioactive macromolecules, proteins or mRNAs, the latter exerting the desired therapeutic effect in target cells via de novo synthesis of their encoded proteins
Replication and Fine Mapping for Association of the C2orf43, FOXP4, GPRC6A and RFX6 Genes with Prostate Cancer in the Chinese Population
Prostate cancer represents the leading cause of male death across the world. A recent genome-wide association study (GWAS) identified five novel susceptibility loci for prostate cancer in the Japanese population. This study is to replicate and fine map the potential association of these five loci with prostate cancer in the Chinese Han population.In Phase I of the study, we tested the five single nucleotide polymorphisms (SNPs) which showed the strongest association evidence in the original GWAS in Japanese. The study sample consists of 1,169 Chinese Hans, comprising 483 patients and 686 healthy controls. Then in phase II, flanking SNPs of the successfully replicated SNPs in Phase I were genotyped and tested for association with prostate cancer to fine map those significant association signals.We successfully replicated the association of rs13385191 (located in the C2orf43 gene, P = 8.60×10(-5)), rs12653946 (P = 1.33×10(-6)), rs1983891 (FOXP4, P = 6.22×10(-5)), and rs339331 (GPRC6A/RFX6, P = 1.42×10(-5)) with prostate cancer. The most significant odds ratio (OR) was recorded as 1.41 (95% confidence interval 1.18-1.68) for rs12653946. Rs9600079 did not show significant association (P = 8.07×10(-2)) with prostate cancer in this study. The Phase II study refined these association signals, and identified several SNPs showing more significant association with prostate cancer than the very SNPs tested in Phase I.Our results provide further support for association of the C2orf43, FOXP4, GPRC6A and RFX6 genes with prostate cancer in Eastern Asian populations. This study also characterized the novel loci reported in the original GWAS with more details. Further work is still required to determine the functional variations and finally clarify the underlying biological mechanisms
Dissimilarity in the Folding of Human Cytosolic Creatine Kinase Isoenzymes
Creatine kinase (CK, EC 2.7.3.2) plays a key role in the energy homeostasis of excitable cells. The cytosolic human CK isoenzymes exist as homodimers (HMCK and HBCK) or a heterodimer (MBCK) formed by the muscle CK subunit (M) and/or brain CK subunit (B) with highly conserved three-dimensional structures composed of a small N-terminal domain (NTD) and a large C-terminal domain (CTD). The isoforms of CK provide a novel system to investigate the sequence/structural determinants of multimeric/multidomain protein folding. In this research, the role of NTD and CTD as well as the domain interactions in CK folding was investigated by comparing the equilibrium and kinetic folding parameters of HMCK, HBCK, MBCK and two domain-swapped chimeric forms (BnMc and MnBc). Spectroscopic results indicated that the five proteins had distinct structural features depending on the domain organizations. MBCK BnMc had the smallest CD signals and the lowest stability against guanidine chloride-induced denaturation. During the biphasic kinetic refolding, three proteins (HMCK, BnMc and MnBc), which contained either the NTD or CTD of the M subunit and similar microenvironments of the Trp fluorophores, refolded about 10-fold faster than HBCK for both the fast and slow phase. The fast folding of these three proteins led to an accumulation of the aggregation-prone intermediate and slowed down the reactivation rate thereby during the kinetic refolding. Our results suggested that the intra- and inter-subunit domain interactions modified the behavior of kinetic refolding. The alternation of domain interactions based on isoenzymes also provides a valuable strategy to improve the properties of multidomain enzymes in biotechnology
Follow-Up of Patients with Multidrug Resistant Tuberculosis Four Years after Standardized First-Line Drug Treatment
Background: In 2004, an anti-tuberculosis (TB) drug resistance survey in Heilongjiang province, China, enrolled 1574 (79%) new and 421 (21%) retreatment patients. Multi-drug resistant (MDR) TB was detected in 7.2% of new and 30.4% of retreatment patients. All received treatment with standardized first-line drug (FLD) regimens. Methodology/Principal Findings: We report treatment outcomes of the 2004 cohort, and long-term outcomes as assessed in the second half of 2008. The reported cure rate for MDR-TB patients was 83% (94/113) among new and 66% (85/128) among retreatment patients (P<0.001). Ten of the 241 MDR-TB patients died during treatment. Of the remaining 231, 129 (56%) could be traced in 2008. The overall recurrence rates among new and retreatment cases were 46% and 66%, respectively (P=0.03). The overall death rates among new and retreatment cases were 25% and 46%, respectively (P=0.02). Forty percent of the traced new cases and 24% of the retreatment cases were alive and without recurrent TB (P=0.01). Of the 16 patients who failed or defaulted from treatment in 2004, only two patients were not re-diagnosed with TB by 2008. Of the 111 (86%) patients with an initial successful treatment outcome 63 (57%) had developed recurrent TB, 40 (36%) had died, 27 (24%) of them died of TB. The follow-up period of four years precluded follow-up of all patients. In a highly conservative sensitivity analysis in which we assumed that all non-included patients were alive and did not have recurrent TB, the recurrence and death rate were 33% and 21%. Conclusions/Significance: Documentation of cure based on conventional smear microscopy was a poor predictor of long term outcomes. MDR-TB patients in Heilongjiang province in China had high recurrence and death rates four years after treatment with standardized FLD regimens, reinforcing the need for early diagnosis and treatment of MDR-TB, including assessment of treatment outcomes with more sensitive laboratory method
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