Antioxidant and DNA damage protecting potentials of polysaccharide extracted from Phellinus baumii using a delignification method.

A delignification method was employed to extract the polysaccharide from the fruiting body of Phellinus baumii. The three parameters, processing temperature, ratio of water to raw material and amount of acetic acid every time were optimized using the Box-Behnken design. As a result, the optimal extraction conditions were: processing temperature 70.3°C, ratio of water to raw material of 34.7mL/g and amount of acetic acid of 0.32mL every time. Under these conditions, the highest yield of polysaccharide (10.28%) was obtained. The main fraction (PPB-2) purified from PPB was composed of fucose, arabinose, galactose, glucose, xylose and mannose, while glucose was the predominant monosaccharide. PPB-2 exhibited noticeable antioxidant activity and strong protection against oxidative DNA damage. These findings implied that acid-chlorite delignification was a superior method to extract the polysaccharide from P. baumii and PPB-2 may be useful for cancer chemoprevention.

Comparison of the preliminary characterizations and antioxidant properties of polysaccharides obtained from Phellinus baumii growth on different culture substrates.

Three polysaccharides (PPB-MB, PPB-MW and PPB-MM) were obtained from the fruiting body of Phellinus baumii growth on different culture substrates (mulberry branches, mixed wood sawdust and an equal combination of the two materials) and their chemical composition was investigated. PPB-MM contained the highest contents of neutral sugar (66.59%) and uronic acid (23.38%), followed by PPB-MW and PPB-MB, with PPB-MW having the highest protein content. The three polysaccharides were all composed of six kinds of monosaccharides, namely fucose, mannose, glactose, xylose, arabinose and glucose. The antioxidant activities of the three polysaccharides were determined using lipid peroxidant inhibition, ABTS radical scavenging, and Fe(2+)-chelating assay. Results showed that PPB-MM exhibited the highest antioxidant properties in all the assays. As a result, an equal combination of mulberry branches and mixed wood sawdust serves as a good culture substrate for producing such antioxidant polysaccharides.

Clinical characteristics and patterns of failure in the parotid region after intensity-modulated radiotherapy for nasopharyngeal carcinoma.

OBJECTIVE: To discuss the clinical characteristics and patterns of failure in the parotid region after intensity-modulated radiotherapy for nasopharygeal carcinoma. MATERIALS AND METHODS: We retrospectively reviewed the charts of 716 patients with nasopharygeal carcinoma who underwent intensity-modulated radiotherapy in our centre from January 2005 to December 2010. Disease recurred in a spared parotid gland in 10 patients (1.4%). There were 2 females and 8 males with a median age of 38.5 (34-53) years. The most common presenting symptom was a swelling in pre-auricular region (7/10). Parotid glands were spared bilaterally in these patients. None of these patients had undergone previous radiotherapy or surgical treatment of the head and neck. The location of periparotid failures were transferred to the pretreatment planning computed tomography for dosimetry analysis. RESULTS: The median time from day 1 of radiotherapy to periparoid recurrence was 17.4 (4.4-40.5) months. The median survivial after periparoid recurrence was 25.1 (5.0-74.5) months. There were 9 (90%) patients with lateral retropharyngeal lymphadenopathy. Seven of the periparotid failures were marginal. Of the 7 marginal failures, 6 occurred at the ipslateral parotid of the primary tumor centre. The average mean dose of the ipslateral parotid was 38.1 (32.3-44.1) Gy. CONCLUSION: Periparotid recurrence is an uncommon pattern of failure after definitive intensity-modulated radiotherapy for nasopharygeal carcinoma. To reduce the risk of periparotid recurrence,one possible strategy is to lessen the dose constraint criteria to ipslateral parotid of the primary tumor centre especially for nasopharygeal carcinoma with lateral retropharyngeal lymphadenopathy.

Clinical outcomes and patterns of failure after intensity-modulated radiotherapy for T4 nasopharyngeal carcinoma.

The goal of this study is to study and report the clinical outcomes and patterns of failure after intensity-modulated radiotherapy (IMRT) for T4 nasopharyngeal carcinoma (NPC). A total of 70 patients treated with IMRT between 2004 and 2009 were eligible for study inclusion. According to the staging system of 2010 AJCC, all the primary tumors were attributed to T4 stage, while the distribution of disease by N stage was N0 in 2, N1 in 23, N2 in 39, N3a in 1, and N3b in 5. The location and extent of locoregional failures were transferred to the pretreatment planning computed tomography for dosimetry analysis. The median follow-up period was 26.8 (range, 4-78) months. The overall 2-year local failure-free survival, regional failure-free survival, distant failure-free survival, and overall survival rate was 82.1%, 92.3%, 73.8%, and 82.5%, respectively. Thirty-three patients had developed treatment failure. Of the 33 patients, 11, 2, and 15 had developed local failure, regional failure, and distant metastasis, respectively, 2 had developed locoregional failure, 1 had developed distant metastasis and failure at the primary, and 2 had developed distant metastasis and failure at the primary and nodal site. Eight of the locoregional failures were marginal. The results of treating T4 NPC with IMRT were excellent. Advanced T4 disease remained difficult to treat. One possible strategy is to lessen the dose constraint criteria of selected neurologic structures. Distant metastasis remains the most difficult treatment challenge for patients with T4 NPC at present, and more effective systemic chemotherapy should be explored.

Auxin-regulated OsRGP1 and OsSuS are involved in gravitropic bending of rice shoot bases.

Gravitropic bending of horizontally-oriented rice shoots results from the differential elongation of cells in the upper and lower halves of the shoot bases. In this study, genes encoding a reversibly glycosylated polypeptide (OsRGP1) and a sucrose synthase (OsSuS) related to sugar metabolism were identified by suppressive subtractive hybridization (SSH) as being differentially expressed in gravibending lower and upper halves of rice shoot bases. RT-PCR was used to monitor OsRGP1 and OsSuS gene expression. The two genes were differentially induced in lower and upper halves of the shoot bases during gravitropism and their expression was regulated by auxin. Gene promoter sequence analysis demonstrated the existence of elements related to auxin. Treatment with the auxin transport inhibitor TIBA inhibited the asymmetric expression of OsRGP1 and OsSuS. In addition, an increase in hexose sugars was detected in the lower half of the shoot bases during gravitropism. Our data suggest that asymmetric redistribution of auxin following gravistimulation results in differentially localized OsRGP1 and OsSuS expression. While asymmetric expression of OsSuS may result in a disproportionate distribution of hexose, asymmetric expression of OsRGP1 could induce cell wall polysaccharide synthesis in the lower half of shoot bases. Therefore hexose and cell wall polysaccharide accumulation in the lower half of rice shoot bases might contribute to cell expansion and subsequent gravitropic bending.

Characterization of OsPIP2;7, a water channel protein in rice.

Aquaporins are water channel proteins that facilitate passage of water and other small neutral molecules across biological membranes. There are usually a large number of members of this family in higher plants, which exhibit various physiological functions and are regulated in a time-specific and particular mode. We have previously shown that a rice gene, OsPIP2;7, was generally up-regulated in roots but down-regulated in shoots at the early stage of chilling stress. Here, OsPIP2;7 was cloned and proved to be an aquaporin with high activity in Xenopus oocytes. OsPIP2;7 was localized mainly in mesophyll cells of leaves. In roots it was detected in the vascular tissues, epidermis cells and exodermis cells at the elongation zone, as well as in the epidermis cells, exodermis cells and root hair at the maturation zone. Yeast cells overexpressing OsPIP2;7 showed a higher survival rate after freeze-thaw stress. Furthermore, OsPIP2;7 enhanced the transpiration rate and tolerance to low temperature when overexpressed in rice. These results indicated that OsPIP2;7 was involved in rapid water transport and maintenance of the water balance in cells, and ultimately improves the tolerance of yeast and rice to low temperature stress.

Transport functions and expression analysis of vacuolar membrane aquaporins in response to various stresses in rice.

The vacuole, a multifunctional organelle of most plant cells, has very important roles in space filling, osmotic adjustment, storage and digestion. Previous researches suggested that aquaporins in the tonoplast were involved in vacuolar functions. The rice genome contains 33 aquaporin genes, 10 of which encode tonoplast intrinsic proteins (TIPs). However, the function of each individual TIP isoform and the integrated function of TIPs under various physiological conditions remain elusive. Here, five rice TIP members were characterized with water and/or glycerol transport activities using the Xenopus oocyte expression system. OsTIP1;2, OsTIP2;2, OsTIP4;1 and OsTIP5;1 possessed water transport activity. OsTIP1;2, OsTIP3;2 and OsTIP4;1 were demonstrated with glycerol transport activity. Rice TIP expression patterns under various abiotic stress conditions including dehydration, high salinity, abscisic acid (ABA) and during seed germination were investigated by real-time PCR. OsTIP1s (OsTIP1;1 and OsTIP1;2) were highly expressed during seed germination, whereas OsTIP3s (OsTIP3;1 and OsTIP3;2) were specifically expressed in mature seeds with a decrease in expression levels upon germination. The results of this research provided a functional and expression profiles of rice TIPs.

[The clinical report of 21 cases of occlusion of atrial septal defect through right chest small incision].

OBJECTIVE: To evaluate the methods and efficacy of atrial septal defect (ASD) occlusion through right chest incision. METHODS: The clinical data of 21 patients with ASD from July 2004 to May 2005 were analyzed retrospectively. Eight patients were male and 13 patients were female, aged from 1 to 70 years old, with the median age of 21 years old. The diameter of ASD was from 8 to 40 mm. All the 21 patients were under general anaesthesia. A 2 to 3 cm incision was made in the 4th intercostals of right side of sternum. With the help of transesophageal or normal transthoracic echocardiography, the occluder was released using monotube unit. RESULTS: All cases were occluded successfully without death. The types of the occluder were from 14 to 46 mm. None failed and had to choose extracorporeal circulation operations. No transfusion and no serious complication such as the occluder dislocated occurred. And no evident of atrial shunt was found when in review echo. CONCLUSIONS: The ASD occlusion through right chest minimal incision is safe, credit, minimal invasive and worth to use widely.

[Symptoms and prognosis of nasopharyngeal carcinoma].

OBJECTIVE: To study the relationship between the symptoms and prognosis of nasopharyngeal carcinoma (NPC). METHODS: The clinical data of 905 M0 NPC patients who received radical radiotherapy from January 1990 to May 1999 were retrospectively studied. Nodal distribution, cranial nerve paralysis, as well as the relationship between symptom duration and prognosis were analyzed. RESULTS: The most common symptom in patients with NPC is neck node metastasis, with an incidence of 40.0% at the time of diagnosis, followed by blood-staining sputum (18.7%) and aural symptoms (17.0%). Node metastasis in the lower neck and supraclavicular region alone was seen in 10 patients (1.1%). Cranial nerve paralysis was found in 179 patients (19.8%). The 5-year overall survival and disease-free survival were significant lower in symptom duration more than 6 months group than in less than 6 months group (71.2% vs 79.8%, P = 0.008 and 51.9% vs 63.6%, P = 0.0008); however, the local control rate between these two group was not significantly different (79.4% vs 83.5%, P = 0.138). CONCLUSION: The symptom duration is associated with the prognosis of NPC. Early diagnosis and treatment are the most important factors in improving the prognosis of NPC.

Nasopharyngeal carcinoma treated by radical radiotherapy alone: Ten-year experience of a single institution.

PURPOSE: To report on our experience in the treatment of nasopharyngeal carcinoma (NPC) by radical radiotherapy alone in our institution during the last decade. METHODS AND MATERIALS: From January 1990 to May 1999, 905 NPC patients were treated and were studied retrospectively. Radical radiotherapy was given to this cohort by conventional technique in a routine dose of 70-72 Gy to the primary tumor and metastatic lymph nodes. In case of residual primary lesion, a boost dose of 8-24 Gy was delivered by either 192Ir afterloading brachytherapy, fractionated stereotactic radiotherapy, conformal radiotherapy, or small external-beam fields. RESULTS: The 5-year and 10-year local-regional control, overall survival, and disease-free survival rates were 81.7% and 76.7%, 76.1% and 66.5%, 58.4% and 52.1%, respectively. In case of residual primary lesions after a dose of 70-72 Gy of conventional external-beam radiotherapy (EBRT), an additional boost was able to achieve a local control of 80.8%, similar to that obtained with primary lesions that completely disappeared at 70-72 Gy (82.6%, p = 0.892). CONCLUSIONS: The treatment results of radical EBRT followed by a boost dose to the residual primary tumor for nasopharyngeal carcinoma in our institution are promising.

[Expression of hepatitis B surface antigen gene in ginseng cell].

The recombinant plasmid pBIBSa containing the HBsAg DNA fragment was transferred into Agrobacterium tumefaciens strain LBA4404 directly. Ginseng cells were co-cultivated with Agrobacterium tumefaciens carrying pBIBSa. The ginseng cell lines carrying HBsAg-S gene were obtained. Transgenic cells were checked for the presence of target gene using PCR and RT-PCR. Samples containing the target gene showed a clear band at the site of 700 bp by agarose electrophoresis analysis (Figs. 2, 3). Expression levels determined by ELISA showed maximum expression levels of 184 ng HBsAg/g FW and 0.009% of the total soluble protein. HBsAg in ginseng cells were located both on the membrane and in the nuclei (Fig. 4).

Induction of defence gene expression by oligogalacturonic acid requires increases in both cytosolic calcium and hydrogen peroxide in Arabidopsis thaliana.

Responses to oligogalacturonic acid (OGA) were determined in transgenic Arabidopsis thaliana seedlings expressing the calcium reporter protein aequorin. OGA stimulated a rapid, substantial and transient increase in the concentration of cytosolic calcium ([Ca2+]cyt) that peaked after ca. 15 s. This increase was dose-dependent, saturating at ca. 50 ug Gal equiv/ml of OGA. OGA also stimulated a rapid generation of H2O2. A small, rapid increase in H2O2 content was followed by a much larger oxidative burst, with H2O2 content peaking after ca. 60 min and declining thereafter. Induction of the oxidative burst by OGA was also dose-dependent, with a maximum response again being achieved at ca. 50 ug Gal equiv/mL. Inhibitors of calcium fluxes inhibited both increases in [Ca2+]cyt and [H2O2], whereas inhibitors of NADPH oxidase blocked only the oxidative burst. OGA increased strongly the expression of the defence-related genes CHS, GST, PAL and PR-1. This induction was suppressed by inhibitors of calcium flux or NADPH oxidase, indicating that increases in both cytosolic calcium and H2O2 are required for OGA-induced gene expression.