两种种植体系下地下水硝态氮含量变化

寿光作为全国闻名的保护地蔬菜产区,过量施肥的现象非常普遍。为了解集约化大棚蔬菜种植区地下水中硝酸盐的含量变化状况,于2003～2005年对寿光市大田（小麦-玉米）、大棚（一年两茬番茄）两种不同的种植体系下农田灌溉水和农村饮用水水井进行了定点跟踪监测。结果表明：大田区地下水中硝态氮的含量随着时间的变化波动很小,农村饮用水中硝态氮含量没有超标现象;随着时间推移,大棚区灌溉水井中硝态氮含量年内（从年初到年末）呈明显的上升趋势,年际间则存在有规律的波动并逐年升高;灌溉水中硝态氮平均含量普遍高于饮用水,浅层地下水明显高于深层地下水;无论大棚区还是大田区,井深不同对地下水的硝态氮含量影响差异很大,浅井中硝态氮的含量明显高于深井。大棚区农村饮用水硝态氮含量超标现象非常普遍,对国家饮用水标准（20mg·L^-1）超标率最高达37.50%,平均为14.06%;对WHO推荐饮用水上限（10mg·L^-1）超标率最高达56.25%,平均为42.19%,硝态氮最高含量45.60mg·L^-1。集约化大棚蔬菜栽培模式已经对农村地下水造成了很大的硝态氮污染,饮用水中较高的硝酸盐含量已经对当地居民的健康构成了潜在的威胁。     

Hemoglobinase activity of a cysteine protease from the ixodid tick Haemaphysalis longicornis

We report here the molecular characterization and possible function of a cysteine protease (termed HlCPL-A) identified in the midgut of the hard tick Haemaphysalis longicornis. HlCPL-A is a 333 amino acid protein belonging to the papain family of the cysteine protease. A construct encoding proHlCPL-A was expressed in Escherichia coli and purified as both procathepsin L and active processed cathepsin L forms. The HlCPL-A gene expression was up-regulated by blood-feeding process. HlCPL-A exhibited substrate specificity against synthetic peptidyl substrates (Z-Phe-Arg-MCA and Z-Arg-Arg-MCA; k_cat / K_m = 0.19 and 0.0023 M^− 1 S^− 1, respectively). The proteolytic activity of HlCPL-A was inhibited by leupeptin, antipain and E-64 but was unaffected by pepstatin. HlCPL-A was capable of degrading bovine hemoglobin at pH 3.2 to 5.6. These results suggest that HlCPL-A may play important roles in the digestion of host hemoglobin in ticks.     

Frequency,clinical characteristics and outcomes of Tropidolaemus species bite envenomations in Malaysia

Pit vipers from the genus Tropidolaemus are identified as one of the common causes of snake bite from venomous species in Malaysia. All Tropidolaemus species bite cases referred to the Remote Envenomation Consultation Services (RECS) between 2015–2021 were included. A total of 4,718 snake-related injuries cases consulted to RECS with 310 (6.6%) involved Tropidolaemus species; of these 190 (61.3%) were T. subannulatus and 120 (38.7%) T. wagleri. All the T. subannulatus cases occurred in Sabah and Sarawak while all cases of T. wagleri occurred in Peninsular Malaysia. The majority of patients were male (74.8%) and adults between 18–59 years old (61.2%). The upper limb (56.6%) was the most frequent anatomical region involved. Most cases were non-occupationally related (75.4%). Bites from both species caused local pain (77.1%) and swelling (27.2%). Most patients complained of mild pain (48.0%). Paracetamol (40.0%) was the most common analgesic prescribed. Antivenom was not indicated in all cases. Two patients were given antivenom inappropriately before RECS consultation. Most patients (54.7%) needed hospital observation for less than 24 hours. No deaths occurred in the group studied.     

Survival outcomes for patients with nasopharyngeal carcinoma in non–endemic region in the UK treated with intensity modulated based radiotherapy 65 Gy in 30 fractions ± weekly cisplatin chemotherapy

BackgroundNasopharyngeal carcinoma (NPC) is rare in the UK. The aim of the current study was to investigate survival outcomes for patients with NPC treated with (chemo)radiotherapy using 65 Gy in 30 fractions in a non-endemic region.Materials and methodsAll consecutive 62 patients with histology proven non-metastatic nasopharyngeal carcinoma diagnosed between January 2009 to June 2019 were included in this retrospective analysis.ResultsMedian age was 59 years (range:19–81). The majority of patients had stage III disease (66.1%). Induction chemotherapy was given in 21% of patients and 82.3% of patients received concomitant systemic therapy. All patients were treated with 65 Gy in 30 fractions. There was disease recurrence in 17.4% patients. The 5-year disease-free, disease-specific and overall survival were 81.9%, 79.2% and 76.4%, respectively. On univariate analysis, disease recurrence was associated with N-stage (p = 0.047) and overall stage group (p = 0.023).ConclusionTo the best of authors’ knowledge, this is the first report of the use of 65 Gy in 30 fractions of radiotherapy ± weekly cisplatin chemotherapy in NPC in a real-world setting. Our results are comparable to that from other non-endemic regions of the world using different dose fractionation of (chemo)radiotherapy. Future randomised control trials are warranted to compare various dose fractionations in these settings.     

Seasonality and density of emerging insects of a mixed lowland broadleaf-podocarp forest floor,Orongorongo Valley,New Zealand

Abstract

Emergence traps were used continuously for 2 years to determine the population density and seasonality of invertebrates in a mixed lowland broadleaf-podocarp forest near Wellington, New Zealand. A total of 53 920 individuals of 21 invertebrate orders was caught. Although more individuals were caught in the first year than in the second, this was not consistent amongst the different groups or species. Dipterans, staphylinid beetles, and solitary wasps were the most numerous insects caught. Diptera, Araneida, Opiliones, and Hymenoptera emerged from the forest floor in every month of the 2 year study. Many other invertebrate groups were active throughout the year but seasonal catches were significantly different with more recorded in summer than in other seasons. Numbers of several species were positively correlated with temperature. Likely effects of the extended invertebrate activity on the forest ecology are discussed.