Influence of Poly(lactic acid) Layer on the Physical and Antibacterial Properties of Dry Bacterial Cellulose Sheet for Potential Acute Wound Healing Materials

Dry bacterial cellulose nanofiber (BC) sheet coated with poly(lactic acid) (PLA) was developed and characterized towards acute wound healing applications. This new approach of PLA coating on BC revealed enhanced physical and antibacterial properties. Commercial BC sheets originated from the manufacturing of nata de coco jelly were dried and coated with the PLA at various concentrations of 2, 4, 6, 8, 10 and 12 % w/v for the purpose of improving the mechanical properties and followed by loading of antiseptic such as benzalkonium chloride (BAC). PLA has been proposed for the use of coating materials at a concentration of 8 %, the biocomposite sheet started exhibiting a low moisture uptake, prolonged swelling in simulated wound fluid solution and high tear (9.17 Nm²/kg) and burst indices (32.5 kPa·m²/g). The 8 % PLA coating revealed porous fiber-like morphology as observed under scanning electron microscope. Therapeutic loading capacity of the BC/8 PLA was substantially higher than the pristine BC. Furthermore strong antimicrobial activities against Staphylococcus aureaus and Escherichia coli were observed for the BC/8PLA biocomposite film. These reports were clearly suggestive of the fact that synthetic biodegradable polymers, such as PLA, may be exploited for the synergistic combination with BC for antimicrobial and acute wound management. This new and modified fiber source material could reduce the dependency on plant based cellulose for more demanding biomedical applications such as wound healing materials, vascular graft, cartilage replacement, drug delivery and tissue engineering.     

Salinity Stress Promote Drought Tolerance of Chenopodium Quinoa Willd

A greenhouse experiment was conducted to investigate the impact of water and salt stress in Quinoa plants (Chenopodium quinoa Willd.). Irrigation treatments using saline solutions of 0 (control), 50(T₁), 200(T₂), 400(T₃), 600(T₄), and 800(T₅) mM sodium chloride (NaCl) were adopted. The results indicated that quinoa plants can tolerate water stress (50%FC) when irrigated with moderately saline water (T₁ and T₂, respectively). Salinity stress increases quinoa drought tolerance in terms of biomass production. Neither osmotic stress nor ions deficiency/toxicity seems to be determinant under T₁ and 100%FC. Salinity induced a significant increase of sodium (Na⁺) and chloride (Cl^?), while reduced magnesium (Mg²⁺) and calcium (Ca²⁺) in stems, leaves, seed’s coating, and seeds. The potassium (K⁺)/Na⁺ ratio never fell below 1 with T₁; yet, fell to 0.78 and 0.89 with T₂ for 100% and 50%FC, respectively. The seed coat limited the passage of possibly toxic concentrations of Na⁺ and Cl^? to seed interior, as high Na⁺ and Cl^? was found in the seed coat.     

Protective effect of rutin on paracetamol- and CCl4-induced hepatotoxicity in rodents

Rutin, a well-known flavonoid was investigated for its possible protective effect against paracetamol- and CCl(4)-induced hepatic damage. Paracetamol produced 100% mortality at the dose of 1 g/kg in mice while pre-treatment of animals with rutin (20 mg/kg) reduced the death rate to 40%. Oral administration of a sub-lethal dose of paracetamol (640 mg/kg) produced liver damage in rats as manifested by the rise in serum level of transaminases (AST and ALT). Pre-treatment of rats with rutin (20 mg/kg) prevented the paracetamol-induced rise in serum enzymes. The hepatotoxic dose of CCl(4) (1.5 ml/kg; orally) also raised the serum AST and ALT levels. The same dose of rutin (20 mg/kg) was able to prevent the CCl(4)-induced rise in serum enzymes. Rutin also prevented the CCl(4)-induced prolongation in pentobarbital sleeping time confirming its hepatoprotectivity. These results indicate that rutin possesses hepatoprotective activity and the presence of this compound in Artemisia scoparia may explain the folkloric use of the plant in liver damage.     

Selenoneine,total selenium,and total mercury content in the muscle of fishes

Levels of the selenium-containing imidazole compound selenoneine and overall organic selenium were measured in the muscle of fishes by speciation analysis. The method involves monitoring ⁸²Se levels by liquid chromatography inductively coupled plasma mass spectroscopy using a gel filtration column. Selenoneine levels were found to be highest in swordfish muscle (concentration 2.8 nmol/g tissue). The selenoneine contents of bigeye tuna, Pacific bluefin tuna, albacore, yellowfin tuna, and alfonsino muscle were 1.3–2.6 nmol/g tissue. In muscle of these fishes, most organic selenium (9–42%) was present as selenoneine. In other fish species, such as Pacific sardine, greeneye, skipjack, Pacific mackerel, horse mackerel, red sea bream, and Japanese barracuda, selenoneine levels were 0.1–1.4 nmol/g tissue, accounting for 3–34% of organic selenium. In contrast, muscle of Japanese conger, Japanese anchovy, chum salmon, Pacific saury, white croaker, and marbled sole contained levels of selenoneine below the level of detection (<0.05 nmol/g tissue). Mercury and selenium contents were 0.01–5.12 nmol/g tissue and 1.4–19.1 nmol/g tissue. The Se-to-Hg molar ratio varied from species to species, ranging from 1 for swordfish to 217 for marbled sole.     

Plastic mulch and indigenous microorganism effects on yield and yield components of cauliflower and tomato in inland and coastal regions of Bangladesh

Production gaps exist in vegetable crops at the farm level in inland and coastal regions of Bangladesh and these gaps could be minimized using different innovative/new agricultural technologies and improved crop management practices. The present study was conducted to compare yield, yield components of cauliflower (Brassica oleracea var. botrytis) and tomato (Solanum lycopersicum L.), and income of smallholder vegetable farmers within different innovative technology practices (with plastic mulch and indigenous microorganism (IMO) vs. without plastic mulch and IMO) at Baliakandi, Rajbari (inland region); and Dashmina, Patuakhali; and Charfession, Bhola (coastal region) in Bangladesh. Yield and gross margins of cauliflower and tomato with plastic mulch and IMO were higher compared with no plastic mulch and no IMO, regardless of location. At Baliakandi, Rajbari, cauliflower yield with plastic mulch was 42.5 t ha^–1, which was a 24.3% improvement over cauliflower yield obtained without plastic mulch (34.2 t ha^–1). At Charfession, Bhola, the highest yield of tomato (57.6 t ha^–1) was obtained with IMO compared with tomato yield (49.2 t ha^–1) without IMO, indicating a 17.1% improvement in yield. Similar trends were obtained at Dashmina, Patuakhali. The difference in gross margin between tomato with and without plastic mulch was US$ 1146 ha^–1 at Dashmina, Patuakhali. Similar trends were obtained in other locations. Innovative agricultural technologies have the potential to increase yield and income of smallholder vegetable farmers in inland and coastal regions of Bangladesh.     

阿克苏河流域平原型水库水质特征研究

本文对阿克苏流域的三座大型平原水库,即上游水库、胜利水库和多浪水库在枯水期和丰水期的水质进行了监测分析,比较了各水库不同水期水质现状,并对监测指标进行了因子分析。结果表明:三座水库枯水期污染程度比丰水期高。水质污染物可分抑制性因子(F1),包括NH3-N、SO42-、Cl-和矿化度以及富营养性污染指标(F2),包括TN、TP和CODMn。目前水库水质主要由第一因子F1决定。枯水期水质污染大小次序为胜利水库>上游水库>多浪水库,而丰水期为多浪水库>胜利水库>上游水库。三座水库水质与引水河流的水质污染指标之间存在极显著相关性。     

新疆经济发展与环境污染关系研究

利用新疆1990-2005年经济与环境统计数据,建立了人均GDP与典型环境指标关系计量模型并分析了两者之间关系。分析结果表明:该时段新疆人均GDP与环境指标之间没有明显的"倒U"型关系;工业废水排放量、工业废气排放量、工业粉尘排放量和工业固体产生量随着经济的发展总体呈现出上升趋势,原因是新疆工业发展较快,还是粗放型为主,环境污染治理投资主要用于提高污染物处理率和达标排放率;仅有工业烟尘排放量呈现出随经济发展降低趋势;新疆目前现状符合经济发展初期随着经济发展环境质量下降的理论。     

新疆天山西部岩面生地衣群落最小面积的初步研究

我们采用Sφrensen和Kulcinsky平均相似性系数，研究了分布在天山西部山脉的岩面生地衣群落的最小面积。结果表明，岩面生地衣群落的定性和定量最小面积分别为30－60cm^2和40－70cm^2，同时证明了整体取样技术适合岩面生地衣的植物群落学研究。     

Hematology and serum biochemistry of captive Sunda pangolin (Manis javanica) in Wildlife Reserves Singapore

The Sunda pangolin (Manis javanica) faces threat of extinction due to illegal trafficking of its scales for the purpose of traditional medicine in the Asian region. Ex-situ captive breeding and reintroduction programs have been identified to be a key effort in the conservation of the species. The establishment of blood parameters for captive Sunda pangolins are vital to assess the health in these animals during health assessments. The objective of this study is to establish blood parameters for captive Sunda pangolins and compare the blood parameters with the established blood reference ranges for rescued wild Sunda pangolins in Singapore. Blood parameters for hematology and serum biochemistry were established from 13 clinically normal captive Sunda pangolins. Male captive Sunda pangolins were found to have significantly (P<0.05) higher potassium compared to the female captive Sunda pangolins. Captive Sunda pangolins were found to have significantly (P<0.05) lower white blood cell count (WBC), neutrophil counts, alanine phosphatase (ALP) and phosphorus and significantly (P<0.05) higher PCV, TP, globulin and blood urea nitrogen (BUN) when compared with rescued wild Sunda pangolins from the previous study.