The pH-responsiveness carrier of sanxan gel beads crosslinked with CaCl2 to control drug release

Natural polysaccharide-based gel carriers have been widely studied for their potential to provide slow and controlled release. Sanxan is an edible polysaccharide produced by Sphingomonas sanxanigenens. In this study, gel beads were prepared using the extrusion dripping method with sanxan as the carrier material and HCl and CaCl2 as the fixing solution. The molecular structure, texture profile, and microstructure of the bead were analyzed. And the swelling characterization and in vitro release of beads were evaluated. The results of Fourier-transform infrared analysis indicate that Ca2+ was used to create an ionically crosslinked structure of sanxan. Texture analyzer and scanning electron microscope studies showed that the acid‑calcium gel exhibited physical resistance and resilience, as well as a distinct gel pore structure. The swelling, dissolution, and drug release of the beads decreased as the amount of CaCl2 increased. Compared to the control (without CaCl2), the release of sanxan beads when 0.5 CaCl2 was added (sanxan carboxyl/Ca2+, by the number of moles M/M) in the stomach and small intestine release decreased by 40.9 % and 49.5 %, respectively. This study indicates that the fabrication of sanxan-Ca2+ crosslinked gel had sustained release characteristics, indicating that sanxan carriers have great potential for gradual and regulated medication delivery.

Tobacco control in China and the road to Healthy China 2030

Healthy China 2030 aims to reduce the adult smoking rate from 27.7% in 2015 to 20% by 2030. Achieving this goal requires a review of the tobacco control measures introduced in China to date, the gaps that remain and the opportunities ahead. In 2008, the World Health Organization introduced six measures to reduce demand for tobacco called MPOWER. The progress China has made in implementing these measure varies: 1) monitor tobacco use and prevention policies. The surveillance on tobacco use has been rigorous, but the monitoring and evaluation of tobacco control policies needs to be strengthened; 2) protect people from tobacco use: pushes for national tobacco control legislation have stalled, but 18 subnational legislations have passed; 3) offer help to quit tobacco use. The accessibility and quality of cessation services needs to be improved; 4) warn about the dangers of tobacco. While there are no pictorial health warnings, tobacco control advocates have launched a series of anti-smoking media campaigns to inform the public; 5) enforce bans on tobacco advertising, promotion, and sponsorship. Legal loopholes and poor enforcement remain challenges; 6) raise taxes on tobacco: cigarettes in China are relatively cheap and increasingly affordable, which demonstrates the need for further tobacco tax increases indexed to inflation and income. China maintains a tobacco monopoly that interferes with tobacco control efforts and fails to regulate tobacco products from the public health perspective. Effective MPOWER measures, which depend upon the removal of tobacco industry interference from policymaking, are key to achieving the goal set by Healthy China 2030.

Enhanced hydrogen adsorption on graphene by manganese and manganese vanadium alloy decoration

In this work, two kinds of novel manganese decorated (G + Mn) and manganese-vanadium co-decorated (G + MnV) graphene composites are synthesized by in situ wet chemical reduction, and their hydrogen storage properties and microstructures are characterized by Sievert-type adsorption apparatus, BET, SEM, TEM/STEM, EDX and EELS. Compared with pristine graphene, Mn decoration marginally increases the hydrogen adsorption capacity of graphene at room temperature and 4 MPa hydrogen pressure from 0.25 wt% to 0.36 wt%. On the other hand, the co-decoration of Mn and V increases the room temperature hydrogen storage capacity of graphene significantly to 1.81 wt% under 4 MPa hydrogen pressure, which is 1.56 wt% higher than the capacity of pristine graphene. The microstructures and valence states of the decorated Mn and Mn-V nanoparticles are investigated by TEM, EDX and EELS analyses, and strong interactions between the decorated nanoparticles and graphene are observed. Based on the results from structural analyses, potential enhancement mechanisms are suggested in terms of the catalytic effects of nanoparticles on graphene hydrogen adsorption. Given the relatively low cost of Mn and V metals compared to noble metals such as Pd, Pt and Au, these results demonstrate a low cost and effective way to significantly enhance the room temperature hydrogen adsorption properties of graphene for potential hydrogen storage applications.

Sera from patients with toxic epidermal necrolysis contain autoantibodies to periplakin

BACKGROUND

The pathophysiological mechanism of toxic epidermal necrolysis (TEN) with extensive bullae that is induced suddenly by drugs is not well understood. The individual patterns and distribution of the widespread mucocutaneous reactions of TEN often show striking similarities with those of paraneoplastic pemphigus (PNP), which is known to involve autoantibodies (aAbs) to members of the plakin family.

OBJECTIVES

To investigate the existence of circulating aAbs to periplakin in the sera of patients with TEN.

METHODS

The presence of circulating aAbs to periplakin was examined using immunoblotting, immunoabsorption and indirect immunofluorescence (IF) analyses. Recombinant protein expression was used to determine the interaction between periplakin and aAbs in the sera of patients with TEN.

RESULTS

Indirect IF studies revealed circulating aAbs in the intercellular area in the epidermis. Interestingly, on rat bladder the staining pattern of the IgG deposits was similar to that observed in patients with PNP. Immunoblotting analysis of the epidermal extracts was used to identify the aAbs in the sera of patients with TEN. These contained circulating aAbs to a 190-kDa protein corresponding to periplakin. Recombinant periplakin and domains of periplakin were prepared in order to confirm the existence of aAbs to periplakin. Immunoblotting with these proteins demonstrated that the sera from patients with TEN reacted with each domain as well as with the full-length periplakin.

CONCLUSIONS

We found that circulating aAbs in the sera of patients with TEN target periplakin. These aAbs might play a role in the pathogenesis of TEN as a humoral autoimmune mechanism.

Important causes of hypoglycaemia in patients with diabetes on peritoneal dialysis

AIM

Diabetes is now the commonest cause of end-stage renal failure, so there are many diabetic patients receiving dialysis therapy. There are several important ways in which dialysis practice can impinge unfavourably on glucose control. This study focuses on the interaction between maltose-derived metabolites in a new peritoneal dialysis fluid and blood glucose measurements using reagent sticks that depend on the glucose dehydrogenase method.

CASE REPORT

We report the cases of three patients, with insulin-treated diabetes and end-stage renal disease treated with peritoneal dialysis, who experienced symptomatic hypoglycaemia with inaccurate glucose readings on reagent strips when converted to icodextrin.

CONCLUSION

Careful teamwork between diabetes and renal physicians and specialist nurses is highly desirable to achieve good glucose control in a group of patients at particular risk of microvascular and macrovascular complications.

The effect of T-2 toxin on IL-1beta and IL-6 secretion in human fetal chondrocytes

The effects of T-2 toxin on IL-1beta and IL-6 secretion in human fetal chondrocytes in vitro were investigated. The evaluation is realised on primary monolayer culture of human fetal epiphyseal chondrocytes with or without PMA stimulation. The levels of supernatant IL-1beta and IL-6 were analyzed by ELISA. As compared with their respective controls, we observed a significant increase of IL-Ibeta and IL-6 in supernatants of chondrocytes cultivated for 24 h with T-2 at 8 ng/ml after PMA stimulation; in the absence of PMA, IL-Ibeta was increased alone after 48 h. The results demonstrated that T-2 toxin could superinduce IL-1beta and IL-6 secretion in chondrocytes. All these data suggested that superinduction of cytokines might be one of the key mechanisms of chondrocyte injuries by T-2 toxin.

Ki-ras mutation and p53 overexpression predict the clinical behavior of colorectal cancer: a Southwest Oncology Group study

We assessed Ki-ras mutations by single-strand conformation polymorphism followed by DNA sequencing, p53 expression by immunohistochemistry, ploidy status, and S-phase fraction in 66 stage II and 163 stage III colon cancer patients enrolled on a randomized trial of surgery followed by observation or adjuvant levamisole or 5-fluorouracil (5FU) plus levamisole (Intergroup Trial 0035) to see whether these factors were independently associated with survival or with differential effects of adjuvant therapy. A Cox proportional hazards survival model was used to describe marker effects and therapy by marker interactions, with adjustment for the clinical covariates affecting survival. A Bonferroni adjustment was used to account for multiple testing. Mutation of the Ki-ras gene was found in 41% of the cancers and was associated with a poor prognosis in stage II but not stage III. In stage II, 7-year survival was 86% versus 58% in those with wild type versus Ki-ras mutations. After adjustment for treatment and clinical variables, the hazard ratio (HR) for death was 4.5; 95% confidence interval (CI), 1.7-12.1 (P = 0.012). p53 overexpression was found in 63% of cancers and was associated with a favorable survival in stage III but not stage II. Seven-year survival in stage III was 56% with p53 overexpression versus 43% with no p53 expression (HR, 2.2; 95% CI, 1.3-3.6; P = 0.012). Aneuploidy was more common in stage III than in stage II (66 versus 47%; P = 0.009) but was not independently related to survival in either group. The proliferative rate was greater in aneuploid than in diploid cancers but was not related to survival. There was no benefit of adjuvant therapy in stage II nor in any of the stage II subgroups defined by mutational status. In stage III, adjuvant therapy with 5FU plus levamisole improved 7-year survival in patients with wild-type Ki-ras (76 versus 44%; HR, 0.4; 95% CI, 0.2-0.8) and in those without p53 overexpression (64 versus 26%; HR, 0.3; 95% CI, 0.1-0.7). Adjuvant therapy did not benefit those with Ki-ras mutations or p53 overexpression. The effects of adjuvant therapy did not differ according to ploidy status or proliferative rate. Ki-ras mutation is a significant risk factor for death in stage II, and the absence of p53 expression is a significant risk factor for death in stage III colon cancer after adjustment for treatment and clinical covariates. Exploratory analyses suggest that patients with stage III colon cancer with wild-type Ki-ras or no p53 expression benefit from adjuvant 5FU plus levamisole, whereas those with Ki-ras mutations or p53 overexpression do not. An independent study will be required to determine whether response to adjuvant therapy in colon cancer depends on mutational status.

[An analysis of complications after implantation of saline-filled silicone prosthesis for augmentation mammaplasty in 294 cases]

Complications after implantation of saline-filled silicone prosthesis for augmentation mammaplasty were analyzed in 294 patients after being followed for 3-5 years. The complications included hematoma, infection, capsular contraction, rupture of the implant, exposure of the implant, psychataxia and poor contour etc. Conditions in which these complications occurred, causes, clinical malifestations, prevention and treatment are discussed.

Cryopreservation of interior spruce (Picea glauca engelmanni complex) embryogenic cultures

Embryogenic cultures of interior spruce derived from 12 full-sib families were subjected to cryopreservation, with a 97 % success rate for 357 genotypes. Analyses suggested that cryotolerance was not related to family ranking (height increment), embryogenic potential or culture dispersability in suspension, and long-term storage in or above liquid nitrogen did not affect regenerative potential. By contrast, differences in cryotolerance among cell lines appeared to be prevalent in certain families. Analysis with a DNA fingerprinting probe used for clonal identification demonstrated no evidence of somaclonal variation as a result of cryopreservation. The results of this work indicate the applicability of cryopreservation as a long-term storage strategy for spruce embryogenic cultures from a wide genetic background.