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11.
We newly sequenced mitochondrial genomes of Spodoptera litura and Cnaphalocrocis medinalis belonging to Lepidoptera to obtain further insight into mitochondrial genome evolution in this group and investigated the influence of optimal strategies on phylogenetic reconstruction of Lepidoptera. Estimation of p-distances of each mitochondrial gene for available taxonomic levels has shown the highest value in ND6, whereas the lowest values in COI and COII at the nucleotide level, suggesting different utility of each gene for different hierarchical group when individual genes are utilized for phylogenetic analysis. Phylogenetic analyses mainly yielded the relationships (((((Bombycoidea + Geometroidea) + Noctuoidea) + Pyraloidea) + Papilionoidea) + Tortricoidea), evidencing the polyphyly of Macrolepidoptera. The Noctuoidea concordantly recovered the familial relationships (((Arctiidae + Lymantriidae) + Noctuidae) + Notodontidae). The tests of optimality strategies, such as exclusion of third codon positions, inclusion of rRNA and tRNA genes, data partitioning, RY recoding approach, and recoding nucleotides into amino acids suggested that the majority of the strategies did not substantially alter phylogenetic topologies or nodal supports, except for the sister relationship between Lycaenidae and Pieridae only in the amino acid dataset, which was in contrast to the sister relationship between Lycaenidae and Nymphalidae in Papilionoidea in the remaining datasets.  相似文献   
12.
The interaction between vascular cells and macrophages is critical during vascular remodeling. Here we report that the scaffolding protein, ezrin-binding phosphoprotein 50 (EBP50), is a central regulator of macrophage and vascular smooth muscle cells (VSMC) function. EBP50 is up-regulated in intimal VSMC following endoluminal injury and promotes neointima formation. However, the mechanisms underlying these effects are not fully understood. Because of the fundamental role that inflammation plays in vascular diseases, we hypothesized that EBP50 mediates macrophage activation and the response of vessels to inflammation. Indeed, EBP50 expression increased in primary macrophages and VSMC, and in the aorta of mice, upon treatment with LPS or TNFα. This increase was nuclear factor-κB (NF-κB)-dependent. Conversely, activation of NF-κB was impaired in EBP50-null VSMC and macrophages. We found that inflammatory stimuli promote the formation of an EBP50-PKCζ complex at the cell membrane that induces NF-κB signaling. Macrophage activation and vascular inflammation after acute LPS treatment were reduced in EBP50-null cells and mice as compared with WT. Furthermore, macrophage recruitment to vascular lesions was significantly reduced in EBP50 knock-out mice. Thus, EBP50 and NF-κB participate in a feed-forward loop leading to increased macrophage activation and enhanced response of vascular cells to inflammation.  相似文献   
13.
Hydrogen sulfide (H2S) produced by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE) in the transsulfuration pathway of homocysteine plays a number of pathophysiological roles. Hyperhomocysteinemia is involved in kidney fibrosis. However, the role of H2S in kidney fibrosis remains to be defined. Here, we investigated the role of H2S and its acting mechanism in unilateral ureteral obstruction (UO)-induced kidney fibrosis in mice. UO decreased expressions of CBS and CSE in the kidney with decrease of H2S concentration. Treatment with sodium hydrogen sulfide (NaHS, a H2S producer) during UO reduced UO-induced oxidative stress with preservations of catalase, copper-zinc superoxide dismutase (CuZnSOD), and manganese superoxide dismutase (MnSOD) expression, and glutathione level. In addition, NaHS mitigated decreases of CBS and CSE expressions, and H2S concentration in the kidney. NaHS treatment attenuated UO-induced increases in levels of TGF-β1, activated Smad3, and activated NF-κB. This study provided the first evidence of involvement of the transsulfuration pathway and H2S in UO-induced kidney fibrosis, suggesting that H2S and its transsulfuration pathway may be a potential target for development of therapeutics for fibrosis-related diseases.  相似文献   
14.
15.
The matrix metalloproteinases (MMPs) are well known to responsible for the degradation of extracellular matrix (ECM) during tissue remodelling such as wound healing, metamorphosis, and regeneration. In present study, gelatinase activities were investigated in normal and retinoic acid (RA)-treated limb regenerates. During the early phase of limb regeneration, gelatinase activities increased greatly, and RA caused the enhanced and prolonged gelatinase activities. We also isolated full length of Hynobius MMP-9, and its spatial and temporal expression profiles were examined in normal, RA-treated, and denervated limb regenerates. Whole mount in situ hybridization showed that the expression of MMP-9 increased in the wound epidermis at the wound healing stage and early phase of dedifferentiation stage. In addition, RA enhanced remarkably its expression both in terms of level and duration in the wound epidermis. However, expression signal of MMP-9 was barely detectable in denervated in limb regenerates. Our results may indicate that MMP-9 plays important role(s) in the dedifferentiation process by participating in ECM degradation and enhancement of MMP-9 expression and activity might be closely related to RA-evoked pattern duplication.  相似文献   
16.
In the present study, we determined that specimens of Kentrochrysalis consimilis collected from South Korea were K. streckeri, rather than K. consimilis, based on morphology, DNA barcodes and nuclear elongation factor 1 alpha (EF‐1α) sequences. The major morphological differences between K. streckeri and K. consimilis include the shape of forewing and hind‐wing pattern elements and male and female genitalia. The DNA barcode analysis of the South Korean specimens and the Russia‐originated K. streckeri showed a maximum sequence divergence of only 0.659% (4 bp), whereas that of the South Korean specimens and Japan‐originated K. consimilis showed a minimum sequence divergence of 2.965% (18 bp), indicating that the Korean specimens are, in fact, K. streckeri and not K. consimilis. Phylogenetic analyses both by Bayesian inference and maximum likelihood methods strongly clustered the South Korean specimens and Russian K. streckeri into one group, excluding K. consimilis. The EF‐1α‐based sequence and phylogenetic analyses of the two species also supported data from the DNA barcode, indicating the distribution of K. streckeri in South Korea, instead of K. consimilis.  相似文献   
17.
Nocturnal stridor is a breathing disorder prevalent in patients with multiple system atrophy (MSA). An improved understanding of this breathing disorder is essential since nocturnal stridor carries a poor prognosis (an increased risk of sudden death). In this study, we aimed to classify types of stridor by sound analysis and to reveal their clinical significance. Patients who met the criteria for probable MSA and had undergone polysomnography (PSG) were recruited. Patients were then assessed clinically with sleep questionnaires, including the Pittsburgh Sleep Quality Index, and the Hoehn and Yahr scale. Nocturnal stridor and snoring were analyzed with the Multi-Dimensional Voice Program. Nocturnal stridor was recorded in 22 patients and snoring in 18 patients using the PSG. Waveforms of stridors were classified into rhythmic or semirhythmic after analysis of the oscillogram. Formants and harmonics were observed in both types of stridor, but not in snoring. Of the 22 patients diagnosed with stridor during the present study, fifteen have subsequently died, with the time to death after the PSG study being 1.9 ± 1.4 years (range 0.8 to 5.0 years). The rhythmic waveform group presented higher scores on the Hoehn and Yahr scale and the survival outcome of this group was lower compared to the semirhythmic waveform group (p = 0.030, p = 0.014). In the Kaplan Meier’s survival curve, the outcome of patients with rhythmic waveform was significantly less favorable than the outcome of patients with semirhythmic waveform (log-rank test, p < 0.001). Stridor in MSA can be classified into rhythmic and semirhythmic types and the rhythmic component signifies a poorer outcome.  相似文献   
18.

Purpose

The Ki-67 labelling index is significant for the management of breast cancer. However, the concordance of Ki-67 expression between preoperative biopsy and postoperative surgical specimens has not been well evaluated. This study aimed to find the correlation in Ki-67 expression between biopsy and surgical specimens and to determine the clinicopathological risk factors associated with discordant values.

Patients and Methods

Ki-67 levels were immunohistochemically measured using paired biopsy and surgical specimens in 310 breast cancer patients between 2008 and 2013. ΔKi-67 was calculated by postoperative Ki-67 minus preoperative levels. The outliers of ΔKi-67 were defined as [lower quartile of ΔKi-67–1.5 × interquartile range (IQR)] or (upper quartile + 1.5 × IQR) and were evaluated according to clinicopathological parameters by logistic regression analysis.

Results

The median preoperative and postoperative Ki-67 levels were 10 (IQR, 15) and 10 (IQR, 25), respectively. Correlation of Ki-67 levels between the two specimens indicated a moderately positive relationship (coefficient = 0.676). Of 310 patients, 44 (14.2%) showed outliers of ΔKi-67 (range, ≤-20 or ≥28). A significant association with poor prognostic factors was found among these patients. Multivariate analysis determined that significant risk factors for outliers of ΔKi-67 were tumor size >1 cm, negative progesterone receptor (PR) expression, grade III cancer, and age ≤35 years. Among 171 patients with luminal human epidermal growth factor receptor 2-negative tumors, breast cancer subtype according to preoperative or postoperative Ki-67 levels discordantly changed in 46 (26.9%) patients and a significant proportion of patients with discordant cases had ≥1 risk factor.

Conclusion

Ki-67 expression showed a substantial concordance between biopsy and surgical specimens. Extremely discordant Ki-67 levels may be associated with aggressive tumor biology. In patients with luminal subtype disease, clinical application of Ki-67 values should be cautious considering types of specimens and clinicopathological risk factors.  相似文献   
19.
Charcot-Marie-Tooth disease type 1E (CMT1E) is a demyelinating motor and sensory neuropathy with peripheral myelin protein 22 (PMP22) point mutations. The objective of this study was to identify genetic causes and determine genotype–phenotype correlation in two Korean demyelinating CMT patients based on whole exome sequencing (WES), histological examination of distal sural nerve, and magnetic resonance imaging (MRI) of leg. WES revealed two de novo PMP22 mutations in the two demyelinating CMT patients, including one novel p.Leu82Pro (c.245T>A) mutation in one patient and one previously reported p.Ser72Leu (c.215C>T) mutation in the other patient. Both mutation sites were located in the well conserved second transmembrane domain. No control had the same mutations. The affected individual with the novel p.Leu82Pro mutation showed early onset, scoliosis, and sensory ataxia with ability to walk without assistance. Histopathological examination showed severe damage of myelin and axons. No compound muscle action potentials (CMAPs) were evoked in the upper or lower limb nerves. Leg MRIs revealed mild fatty infiltration of the bilateral peronei muscles consistent with clinical manifestations. The patient with the p.Ser72Leu mutation showed developmental delay in infancy. No CMAPs were elicited. However, she was also able to walk without assistance. In spite of markedly severe electrophysiological defects, leg MRIs showed almost normal findings except slight muscle atrophies of the lower legs. Both patients presented similar clinical features including no CMAPs in electrophysiological tests and mild fatty replacement in the lower leg MRI. Therefore, there was a good genotype–phenotype correlation in both cases.  相似文献   
20.

Purpose

To investigate associations between serum 25-hydroxyvitamin D levels and dry eye syndrome (DES), and to evaluate the differential effect of vitamin D on ocular diseases including age-related macular disease (AMD), diabetic retinopathy (DR), cataract, and DES.

Methods

A total of 16,396 participants aged >19 years were randomly selected from the Korean National Health and Nutrition Examination Survey. All participants participated in standardized interviews, blood 25-hydroxyvitamin D level evaluations, and comprehensive ophthalmic examinations. DES was defined by a history of clinical diagnosis of dry eyes by a physician. The association between vitamin D and DES was compared to the associations between vitamin D and AMD, DR, cataract, and DES from our previous studies.

Results

The odds of DES non-significantly decreased as the quintiles of serum 25-hydroxyvitamin D levels increased (quintile 5 versus 1, OR = 0.85, 95%CI: 0.55–1.30, P for trend = 0.076) after adjusting for potential confounders including age, sex, hypertension, diabetes, smoking status, and sunlight exposure times. The relative odds of DES (OR = 0.70, 95% CI: 0.30–1.64) and cataract (OR = 0.76, 95% CI: 0.59–0.99) were relatively high, while those of DR (OR = 0.37, 95% CI: 0.18–0.76) and late AMD (OR = 0.32, 95% CI: 0.12–0.81) were lower in men.

Conclusions

The present study does not support an association between serum 25-hydroxyvitamin D levels and DES. The preventive effect of serum 25-hydroxyvitamin D may be more effective for DR and late AMD than it is for cataract and DES.  相似文献   
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