The molecular evolution of PL10 homologs

<p>Abstract</p> <p>Background</p> <p><it>PL10 </it>homologs exist in a wide range of eukaryotes from yeast, plants to animals. They share a DEAD motif and belong to the DEAD-box polypeptide 3 (<it>DDX3</it>) subfamily with a major role in RNA metabolism. The lineage-specific expression patterns and various genomic structures and locations of <it>PL10 </it>homologs indicate these homologs have an interesting evolutionary history.</p> <p>Results</p> <p>Phylogenetic analyses revealed that, in addition to the sex chromosome-linked <it>PL10 </it>homologs, <it>DDX3X </it>and <it>DDX3Y</it>, a single autosomal <it>PL10 </it>putative homologous sequence is present in each genome of the studied non-rodent eutheria. These autosomal homologous sequences originated from the retroposition of <it>DDX3X </it>but were pseudogenized during the evolution. In rodents, besides <it>Ddx3x </it>and <it>Ddx3y</it>, we found not only <it>Pl10 </it>but another autosomal homologous region, both of which also originated from the <it>Ddx3x </it>retroposition. These retropositions occurred after the divergence of eutheria and opossum. In contrast, an additional X putative homologous sequence was detected in primates and originated from the transposition of <it>DDX3Y</it>. The evolution of <it>PL10 </it>homologs was under positive selection and the elevated Ka/Ks ratios were observed in the eutherian lineages for <it>DDX3Y </it>but not <it>PL10 </it>and <it>DDX3X</it>, suggesting relaxed selective constraints on <it>DDX3Y</it>. Contrary to the highly conserved domains, several sites with relaxed selective constraints flanking the domains in the mammalian <it>PL10 </it>homologs may play roles in enhancing the gene function in a lineage-specific manner.</p> <p>Conclusion</p> <p>The eutherian <it>DDX3X/DDX3Y </it>in the X/Y-added region originated from the translocation of the ancient <it>PL10 </it>ortholog on the ancestral autosome, whereas the eutherian <it>PL10 </it>was retroposed from <it>DDX3X</it>. In addition to the functional <it>PL10</it>/<it>DDX3X</it>/<it>DDX3Y</it>, conserved homologous regions on the autosomes and X chromosome are present. The autosomal homologs were also derived from <it>DDX3X</it>, whereas the additional X-homologs were derived from <it>DDX3Y</it>. These homologs were apparently pseudogenized but may still be active transcriptionally. The evolution of <it>PL10 </it>homologs was positively selected.</p

Evaluation of unilateral cage-instrumented fixation for lumbar spine

<p>Abstract</p> <p>Background</p> <p>To investigate how unilateral cage-instrumented posterior lumbar interbody fusion (PLIF) affects the three-dimensional flexibility in degenerative disc disease by comparing the biomechanical characteristics of unilateral and bilateral cage-instrumented PLIF.</p> <p>Methods</p> <p>Twelve motion segments in sheep lumbar spine specimens were tested for flexion, extension, axial rotation, and lateral bending by nondestructive flexibility test method using a nonconstrained testing apparatus. The specimens were divided into two equal groups. Group 1 received unilateral procedures while group 2 received bilateral procedures. Laminectomy, facectomy, discectomy, cage insertion and transpedicle screw insertion were performed sequentially after testing the intact status. Changes in range of motion (ROM) and neutral zone (NZ) were compared between unilateral and bilateral cage-instrumented PLIF.</p> <p>Results</p> <p>Both ROM and NZ, unilateral cage-instrumented PLIF and bilateral cage-instrumented PLIF, transpedicle screw insertion procedure did not revealed a significant difference between flexion-extension, lateral bending and axial rotation direction except the ROM in the axial rotation. The bilateral group's ROM (-1.7 ± 0. 8) of axial rotation was decreased significantly after transpedicle screw insertion procedure in comparison with the unilateral group (-0.2 ± 0.1). In the unilateral cage-instrumented PLIF group, the transpedicle screw insertion procedure did not demonstrate a significant difference between right and left side in the lateral bending and axial rotation direction.</p> <p>Conclusions</p> <p>Based on the results of this study, unilateral cage-instrumented PLIF and bilateral cage-instrumented PLIF have similar stability after transpedicle screw fixation in the sheep spine model. The unilateral approach can substantially reduce exposure requirements. It also offers the biomechanics advantage of construction using anterior column support combined with pedicle screws just as the bilateral cage-instrumented group. The unpleasant effect of couple motion resulting from inherent asymmetry was absent in the unilateral group.</p

High-tech Start-up Ecosystems in East Asian Agglomerations: Are They Different From the West?

Start-up ecosystems within regional agglomerations have been intensively studied in Western countries, but much less in East Asia. Therefore, little is known about the specific features of East Asian start-up ecosystems. We study the high-tech start-up ecosystems within four leading East Asian agglomerations: Tokyo, Seoul, Suzhou and Chongqing. Our case studies of these start-up ecosystems reveal that they differ in various important aspects from their Western counterparts. They are located within very large urban agglomerations. Consequently, start-ups firms are co-located with many leading domestic and international firms, and research institutions. However, the networks with these partners tend to be relatively weak and segregated. Government support is strong and results in broad financial assistance for start-ups. We also find differences in the growth and internationalization across the four East Asian start-up ecosystems which can be related to features of the national economies they are located in. Overall, our findings suggest that studies of start-up ecosystems need to consider their regional institutional and cultural context, as there are strong differences between Western and East Asian countries

Target Nanodiamonds as Phenotype Specific Photoacoustic Contrast Agents for Breast Cancer

AIM: The aim is to develop irradiated nanodiamonds (INDs) as a molecularly-targeted contrast agent for high resolution and phenotype-specific detection of breast cancer with photoacoustic (PA) imaging. MATERIALS & METHODS: The surface of acid treated radiation-damaged nanodiamonds was grafted with polyethylene glycol (PEG) to improve its stability and circulation time in blood, followed by conjugation to an anti-Human epidermal growth factor receptor-2 (HER2) peptide (KCCYSL) with a final nanoparticle size of ca. 92 nm. Immunocompetent mice bearing orthotopic HER2 positive or negative tumors were administered INDs and PA imaged using an 820-nm near infrared laser. RESULTS: PA images demonstrated that INDs accumulate in tumors and completely delineated the entire tumor within 10 hours. HER2 targeting significantly enhanced imaging of HER2-positive tumors. Pathological examination demonstrated INDs are non-toxic. CONCLUSIONS: PA technology is adaptable to low-cost bedside medicine, and with new contrast agents described herein, PA can achieve high resolution (sub-mm) and phenotype specific monitoring of cancer growth

Adult mortality of diseases and injuries attributable to selected metabolic, lifestyle, environmental, and infectious risk factors in Taiwan: A comparative risk assessment

Background: To facilitate priority-setting in health policymaking, we compiled the best available information to estimate the adult mortality (>30 years) burden attributable to 13 metabolic, lifestyle, infectious, and environmental risk factors in Taiwan. Methods: We obtained data on risk factor exposure from nationally representative health surveys, cause-specific mortality from the National Death Registry, and relative risks from epidemiological studies and meta-analyses. We applied the comparative risk assessment framework to estimate mortality burden attributable to individual risk factors or risk factor clusters. Results: In 2009, high blood glucose accounted for 14,900 deaths (95% UI: 11,850-17,960), or 10.4% of all deaths in that year. It was followed by tobacco smoking (13,340 deaths, 95% UI: 10,330-16,450), high blood pressure (11,190 deaths, 95% UI: 8,190-14,190), ambient particulate matter pollution (8,600 deaths, 95% UI: 7,370-9,840), and dietary risks (high sodium intake and low intake of fruits and vegetables, 7,890 deaths, 95% UI: 5,970-9,810). Overweight-obesity and physical inactivity accounted for 7,620 deaths (95% UI: 6,040-9,190), and 7,400 deaths (95% UI: 6,670-8,130), respectively. The cardiometabolic risk factors of high blood pressure, high blood glucose, high cholesterol, and overweight-obesity jointly accounted for 12,120 deaths (95% UI: 11,220-13,020) from cardiovascular diseases. For domestic risk factors, infections from hepatitis B virus (HBV) and hepatitis C virus (HCV) were responsible for 6,300 deaths (95% UI: 5,610-6,980) and 3,170 deaths (95% UI: 1,860-4,490), respectively, and betel nut use was associated with 1,780 deaths from oral, laryngeal, and esophageal cancer (95% UI: 1,190-2,360). The leading risk factors for years of life lost were similar, but the impact of tobacco smoking and alcohol use became larger because the attributable deaths from these risk factors occurred among young adults aged less than 60 years. Conclusions: High blood glucose, tobacco smoking, and high blood pressure are the major risk factors for deaths from diseases and injuries among Taiwanese adults. A large number of years of life would be gained if the 13 modifiable risk factors could be removed or reduced to the optimal level

In vivo photoacoustic imaging of breast cancer tumor with HER2-targeted nanodiamonds

Radiation-damaged nanodiamonds (NDs) are ideal optical contrast agents for photoacoustic (PA) imaging in biological tissues due to their good biocompatibility and high optical absorbance in the near-infrared (NIR) range. Acid treated NDs are oxidized to form carboxyl groups on the surface, functionalized with polyethylene glycol (PEG) and human epidermal growth factor receptor 2 (HER2) targeting ligand for breast cancer tumor imaging. Because of the specific binding of the ligand conjugated NDs to the HER2-overexpressing murine breast cancer cells (4T1.2 neu), the tumor tissues are significantly delineated from the surrounding normal tissue at wavelength of 820 nm under the PA imaging modality. Moreover, HER2 targeted NDs (HER2-PEG-NDs) result in higher accumulation in HER2 positive breast tumors as compared to non-targeted NDs after intravenous injection (i.v.). Longer retention time of HER-PEG-NDs is observed in HER2 overexpressing tumor model than that in negative tumor model (4T1.2). This demonstrates that targeting moiety conjugated NDs have great potential for the sensitive detection of cancer tumors and provide an attractive delivery strategy for anti-cancer drugs

Macrolide resistance and genotypic characterization of Streptococcus pneumoniae in Asian countries: a study of the Asian Network for Surveillance of Resistant Pathogens (ANSORP)

Objectives: To characterize mechanisms of macrolide resistance among Streptococcus pneumoniae from 10 Asian countries during 1998-2001. Methods: Phenotypic and genotypic characterization of the isolates and their resistance mechanisms. Results: Of 555 isolates studied, 216 (38.9%) were susceptible, 10 (1.8%) were intermediate and 329 (59.3%) were resistant to erythromycin. Vietnam had the highest prevalence of erythromycin resistance (88.3%), followed by Taiwan (87.2%), Korea (85.1%), Hong Kong (76.5%) and China (75.6%). Ribosomal methylation encoded by erm(B) was the most common mechanism of erythromycin resistance in China, Taiwan, Sri Lanka and Korea. In Hong Kong, Singapore, Thailand and Malaysia, efflux encoded by mef(A) was the more common in erythromycin-resistant isolates. In most Asian countries except Hong Kong, Malaysia and Singapore, erm(B) was found in >50% of pneumococcal isolates either alone or in combination with mef(A). The level of erythromycin resistance among pneumococcal isolates in most Asian countries except Thailand and India was very high with MIC90s of >128 mg/L. Molecular epidemiological studies suggest the horizontal transfer of the erm(B) gene and clonal dissemination of resistant strains in the Asian region. Conclusion: Data confirm that macrolide resistance in pneumococci is a serious problem in many Asian countries

Photoacoustic contrast imaging of biological tissues with nanodiamonds fabricated for high near-infrared absorbance

This is the publisher's version, also available electronically from http://biomedicaloptics.spiedigitallibrary.org/article.aspx?articleid=1619539Radiation-damaged nanodiamonds (DNDs) are potentially ideal optical contrast agents for photoacoustic (PA) imaging in biological tissues due to their low toxicity and high optical absorbance. PA imaging contrast agents have been limited to quantum dots and gold particles, since most existing carbon-based nanoparticles, including fluorescent nanodiamonds, do not have sufficient optical absorption in the near-infrared (NIR) range. A new DND by He+ ion beam irradiation with very high NIR absorption was synthesized. These DNDs produced a 71-fold higher PA signal on a molar basis than similarly dimensioned gold nanorods, and 7.1 fmol of DNDs injected into rodents could be clearly imaged 3 mm below the skin surface with PA signal enhancement of 567% using an 820-nm laser wavelength

Increased risk of benign paroxysmal positional vertigo in patients with anxiety disorders: a nationwide population-based retrospective cohort study

BACKGROUND: The objective of this study was to evaluate the risk of benign peripheral persistent vertigo (BPPV) among patients with anxiety disorders by using the Taiwan National Health Insurance Research Database (NHIRD). METHODS: We conducted a retrospective study of 15,470 participants (7735 anxiety disorder patients and 7735 control patients) selected from the NHIRD. Patients were observed for a maximum of 9 years to determine the rates of newly diagnosed BPPV. A Cox regression model was used to evaluate the risk of BPPV among the patients with anxiety disorders. RESULTS: During the 9-year follow-up period, 178 (2.05 per 1000 person-years) anxiety disorder patients and 71 (0.81 per 1000 person-years) control patients were diagnosed with BPPV. The incidence risk ratio of BPPV between anxiety disorder patients and control patients was 2.52 (95 % confidence interval [CI], 1.90–3.37, P < .001). After adjustment for age, sex, and comorbidities, patients with anxiety disorders were found to be 2.17 times more likely to develop BPPV (95 % CI, 1.63–2.90, P < .001) than the control patients. Furthermore, female sex (HR = 1.81, 95 % CI, 1.31–2.50, P < .001) and cerebrovascular disease (HR = 1.53, 95 % CI, 1.00–2.34, P = .050) were independent risk factors for developing new-onset BPPV in patients with anxiety disorders. CONCLUSIONS: Anxiety disorder patients may have an increased risk of developing BPPV, especially those who are female or have cerebrovascular disease