Search

β-1,3 − 1,4-gluconases can specifically hydrolyze the adjacent β-1,4 glycoside bond of β-1,3 in β-glucan, which is widely used in food, brewing and feed industries. Its sources include bacteria, fungi, and plant endosperm cell walls, most β-1,3 − 1,4-glucanases lose their activity when the temperature exceeds 65 ℃. In this study, we selected and modified the β-1,3 − 1,4-glucanase (PlicA) gene from Paenibacillus and expressed it in Escherichia coli BL21 (DE3). Adding disulfide bonds by rational design increased the optimal temperature of the enzyme from 55 ℃ to 80 ℃, and temperature stability was also improved. The optimum pH of the modified β-1,3 − 1,4-gluconanase (Eccsl69) was 9.0–10.0. The enzyme activity in 16.9 U/mL of Eccsl69 was measured at 540 nm with 0.8% gluan as the substrate, and a nickel column purified specific enzyme activity of 320 U/mg was determined. The Km and Vmax values of Eccsl69 using barley β-glucan as substrate were 1.5 mg/ml and 8.3 mol/min·mg. The structure of the β-1,3 − 1,4-glucanase Eccsl69 tended to be stable after molecular dynamics simulation for approximately 20 ns. The enzyme was successfully applied in the pulping and papermaking field for the first time, and the pulp freeness was adjusted from 55.0 °SR to 47 °SR, which enhanced water filtration. This study provides a successful strategy for improving the heat resistance of Eccsl69, which is promising for its application in pulping and paper making industries.

OBJECTIVE To compare the therapeutic effects of metformin (Met) and laparoscopic ovarian drilling (LOD) in clomiphene and insulin-resistant patients with polycystic ovary syndrome (CIRPCOS). METHODS A total of 110 patients were randomly divided into two groups. One group was administered Met (n = 55), while the other group underwent LOD (n = 55). Rates of ovulation, pregnancy, and abortion were compared between both groups. RESULTS Rates of normal menstruation, ovulation, and pregnancy in the LOD group were higher than in the Met group: 76.4% (42/55) vs. 58.2% (32/55), P < 0.04; 50.8% (11/258) vs. 33.5% (94/281), P < 0.001; 38.2% (21/55) vs. 20.0% (11/55), P < 0.03. The difference in the early abortion rate between both groups was not statistically significant. CONCLUSIONS Although Met can significantly improve a patient's insulin resistance, we found that in patients diagnosed with CIRCPOS, LOD can be much more effective in improving rates of normal menstruation, ovulation, and pregnancy.

Primary inflammatory myofibroblastic tumor (IMT) of the breast is extremely rare; only 19 cases have been reported in the English literature. In the present study, we present a case of IMT in a 56-year-old female patient who was admitted to our hospital due to a mass found in her right breast. Mammogram and ultrasound revealed a well-circumscribed mass and surgery was performed. Histopathologically, the lesion was composed of spindle and inflammatory cells, including plasma cells and lymphocytes. Mitotic figures were not observed. Immunohistochemically, the tumor cells were positive for SM-actin, anaplastic lymphoma kinase (ALK) and vimentin and focal positive for desmin, but negative for NSE, S-100, CD117, CD34, NF, CD21, CD35 and CD68. Thus, we made a diagnosis of IMT and advised regular follow-up. However, the patient had local recurrence and metastasis to the left groin area 3, 7 and 10 months after the initial surgery. Notably, the histopathological characteristics of the recurrent and metastatic foci were similar to those of the initial specimen, but mitotic figures were clearly observed. Thus, we conclude that IMT shows occasionally malignant biological behavior although it is a neoplasm of intermediate biological potential that frequently recurs and rarely metastasizes. We advise that clinical physicians should regularly follow up patients after focal resection for IMT.

Almost all gnathostomes or jawed vertebrates (including osteichthyans, chondrichthyans, ‘acanthodians’ and most placoderms) possess paired pectoral and pelvic fins. To date, it has generally been believed that antiarch placoderms (extinct armoured jawed fishes from the Silurian–Devonian periods) lacked pelvic fins. The putative absence of pelvic fins is a key character bearing on the monophyly or paraphyly of placoderms. It also has far-reaching implications for studying the sequence of origin of pelvic girdles versus that of movable jaws in the course of vertebrate evolution. Parayunnanolepis xitunensis represents the only example of a primitive antiarch with extensive post-thoracic preservation, and its original description has been cited as confirming the primitive lack of pelvic fins in early antiarchs. Here, we present a revised description of Parayunnanolepis and offer the first unambiguous evidence for the presence of pelvic girdles in antiarchs. As antiarchs are placed at the base of the gnathostome radiation in several recent studies, our finding shows that all jawed vertebrates (including antiarch placoderms) primitively possess both pectoral and pelvic fins and that the pelvic fins did not arise within gnathostomes at a point subsequent to the origin of jaws.

The morphology of the arthrodire placoderm Yujiangolepis liujingensis Wang, Pan & Wang, 1998, from the Lower Devonian of Guangxi is redescribed, and compared to that of the basal arthrodires Antarctaspis White, 1968 from Antarctica, Toombalepis Young & Goujet, 2003 and Wuttagoonaspis Ritchie, 1973 from Australia, and Yiminaspis Dupret, 2008 from south China. A very small plate of the skull roof at the junction of the nuchal, marginal, postorbital, and paranuchal plates is considered as the vestigial homologue of the anterior paranuchal plate in the Petalichthyida and Acanthothoraci. Yujiangolepis is attributed to the family ‘Antarctaspididae’ White, 1968, together with the genera Antarctaspis and Toombalepis. A computerized phylogenetic analysis resolved Yujiangolepis as the most basal arthrodire, and the family ‘Antarctaspididae’ appears paraphyletic, Yujiangolepis being possibly the most basal. The family Wuttagoonaspididae contains the genera Wuttagoonaspis and Yiminaspis, and remains monophyletic. A Chinese origin of the ‘Antarctaspididae’ is proposed, together with a southward dispersal into Gondwana during the Early Emsian.

Introduced the notion of symmetric circulant matrix on skew field, an easy method is given to determine the inverse of symmetric circulant matrix on skew field , with this method , we derived the formula of determine inverse about several special type of symmetric circulant matrix.

In the female population in Asia, systematic investigation concerning alterations in cancer-related genes in breast carcinoma is rare, and the correlation among oncogene or suppressor gene expression with tumor cell apoptosis, cell cycle regulation and tumor cell autophagy remains to be clarified. In this study, a tissue microarray consisting of 360 individual samples from three different breast tissues was generated. By comparing the expression of the tumor-suppressor genes (BRCA1, BECN1, CCND1, PTEN and UVRAG) in ductal breast cancer and normal breast tissues, respectively, we were able to assign changes in the expression of these mRNAs to specific stages and allocate them to define the roles in the multi‑step process of breast carcinogenesis. Tumor-suppressor genes, such as BRCA1 and BECN1, usually had lower signals in the carcinomatous tissues (10.2 and 6.6%) compared to the normal tissues (31 and 32.6%), while stronger positive dots (positive cells >30%) usually existed in the normal tissues. The patients in the oldest age group had the lowest expression rate. Only BECN1 and CCND1 expression showed a significant association with patient age (p=0.030 and p=0.003). A significant association was observed between BRCA1 and BECN1 expression and tumor size (p=0.028 and p=0.021). BECN1 gene expression was positively correlated with UVRAG and PTEN expression (p=0.006 and p=0.000). CCND1 was negatively correlated with PTEN, BECN1 and BRCA1 expression (p=0.011, p=0.000 and p=0.000). Abnormal expression of BRCA1, BECN1, CCND1, PTEN and UVRAG may play a role in human breast carcinogenesis through dysregulated mRNA expression. Overexpressed CCND1 may shorten the G1 phase of the cell cycle, suppress cell apoptosis and contribute to the formation of invasive ductal carcinoma (IDC).

Objective To compare the therapeutic effects of metformin (Met) and laparoscopic ovarian drilling (LOD) in clomiphene and insulin-resistant patients with polycystic ovary syndrome (CIRPCOS).