Cryopreservation of Digitalis lanata Ehrh. cell cultures: Preculture and freeze tolerance

Cryopreservation experiments were performed with Digitalis lanata cell cultures. The main stress was laid on the behaviour of the cells during the preculture period and the capacity of various preculture additives to induce freeze tolerance. The following compounds were used as preculture additives: trehalose, mannitol, sucrose, melibiose, proline, and sorbitol. They are listed in the order of their respective efficiency. Using trehalose, high post-thaw viability rates were achieved and the cells resumed growth after a short lag period. Melibiose was used as a preculture additive for the first time. Its suitability was in the range of that of sucrose. Proline and sorbitol were not able to induce freeze tolerance in Digitalis cells. Cell viability showed a considerable decrease at the beginning of the preculture period. This reduction was found to be transient in the presence of trehalose, mannitol, sucrose, and melibiose. The damaging effects of proline and sorbitol were too severe to be compensated for by the cells. The PAL activity increased markedly in the presence of proline, whereas the trehalose-treated and the control cells behaved nearly identical to one another.     

Some factors affecting the in vitro invasion of HeLa cells by Trypanosoma cruzi

The penetration of metacyclic forms of Trypanosoma cruzi into HeLa cells after different treatments was studied. When cell development was synchronized by two different processes, maximum rates of parasitization occurred during the S phase of cell cycle (29.48 and 24.3%). However, when cells were treated with trypsin (0.1%), parasitization rates appeared to be lower than controls, reaching values similar to controls 14 h after the beginning of the treatment. Infection values remained unaltered after treatment with colcemid (0.6 μg ml^?1). Cell treatment either with valinomycin (1 μg ml^?1) or with actinomycin D (250 μg ml^?1) caused a marked decrease in the percentage of parasitization. When cells were treated and infected in the presence of tunicamycin (100 ng ml^?1), parasitization rates were increased (14.7%) compared to control cells (6%). On the other hand, no differences in parasitization rates were observed when cells were treated with cycloheximide (100 μg ml^?1). Infection in a low redox medium (?100 mV) resulted in considerable increase in parasitization.     

Effects of some thermal, chemical and mechanical treatments on lipase activity in Shammi goat milk

The effects of heating (20, 37 or 50 °C), cooling (5 °C), pasteurisation (71 °C for 15 s), boiling (100 °C), agitation (5 or 10 min), pH (acid or alkaline), and addition of chemicals such as silver and lead nitrates, copper sulphate and sodium chloride on lipase activity in Shammi goat milk were studied. There were non-significant differences (P < 0.01) in chemical composition between Shammi goat milk and Arabi cow milk. Lipase activity in Shammi goat milk was non-significantly (P < 0.01) lower than in Arabi cow milk. Lipase activity in milk of Shammi goats and Arabi cows was reduced when the milk was subjected to heating, cooling, pasteurisation, boiling, or when chemicals or acid was added, whereas in agitated and alkaline milk, the lipase activity was increased. The increase following agitation was greater after 10 min than 5 min. It can be concluded that heating, pasteurising, boiling, cooling, addition of certain chemicals and acidity are means by which lipase activity in milk can be reduced.     

Pre-weaning management of calves on commercial dairy farms and its influence on calf welfare and mortality

Welfare and management of calves is of increasing interest and also influences performance of these animals in later life. The aim of this study was to assess management and environmental conditions under which pre-weaned dairy calves are reared on commercial Irish dairy farms. We included 47 spring-calving, pasture-based herds in this study. Herd and animal-specific data, such as mortality rate, age and breed, were gathered from all participants via the HerdPlus® database. Information pertaining to management practices was collected by conducting an interview with the principal calf rearer, while an assessment of calf housing facilities was conducted to identify conditions calves were reared in. The environmental assessment included measurements of space allowance per calf, as well as feeding equipment hygiene. To assess calf behaviour video observations were used, while accounting for the number of calves present in a group and the space available per calf. Faecal samples were also collected to determine the presence of enteric pathogens among calves. To compare calf space allowance, group size and presence of enteric pathogens early and late in the calving season each farm was visited twice. Calf mortality was not associated with either herd size, space allowance per calf or post-colostrum feeding practices. Higher calf mortality was identified among herds which reported experiencing an on-set of calf pneumonia during weeks 8 to 10 of the calving season. This study demonstrates that factors associated with calf welfare on commercial Irish dairy farms (e.g. space allowance, mortality rate) are independent of herd size. Some management practices however, such as methods used for treating health issues can affect rates of calf mortality experienced. Calf mortality, for example, was lower in herds which treated diarrhoea cases by administering electrolytes, while continuing to offer milk. Behavioural observations indicate that smaller group sizes could promote expression of positive behaviours, potentially resulting from an overall improvement in welfare. Space allowance per calf was not associated with observed behaviour frequencies. We also identified that similar rates of calf mortality are experienced across herds of different sizes.     

Influence of culinary treatment on the concentration and on the bioavailability of cadmium,chromium, copper,and lead in seafood

BackgroundSeafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed.MethodsBoiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed.ResultsThe analytes concentration in seafood without culinary treatment varied from 0.0030 μg g⁻¹ (shrimp) to 0.338 μg g⁻¹ (oyster) for Cd; 0.010 μg g⁻¹ (squid) to 0.036 μg g⁻¹ (oyster) for Cr; 0.088 μg g⁻¹ (scallop) to 8.63 μg g⁻¹ (oyster) for Cu, and < 0.005 μg g⁻¹ (shrimp, squid and oyster) to 0.020 μg g⁻¹ (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments.ConclusionCadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.     

Facilitating Establishment of Advance Regeneration of Pterocarpus santalinus L.—An Endangered Tree Species from India

Red sanders (Pterocarpus santalinus L.) is an endangered and endemic tropical tree species from India in need of restoration. This study evaluated options for improving establishment of its advance regeneration in degraded forests. Using randomized complete block design, the effect of silvicultural treatments involving prescribed fire, in combination with disking, singling, disking with singling, and control (no treatment) on survival and growth of advanced regeneration were evaluated for a period of 2 years. Results indicate that the treatments served to ameliorate microsite conditions resulting in better survival and growth. Seedlings with fewer coppice shoots, treatments with a singling component, and treatments with disking component showed better survival and growth. The number and height of other neighboring seedlings and trees also influenced seedling establishment. Seedlings showed significantly higher survival results in the prescribed fire with disking (disking with prescribed burn [DPB]: 96%) and prescribed fires with disking and singling (singling plus disking with prescribed burn [SDPB]: 94%) treatments. Similarly, tall seedlings and those with larger root collar diameters accrued significantly higher volume growth in DPB (87%) and SDPB (97%) treatments. Although seedlings showed similar increments in DPB and SDPB treatments, better survival due to singling indicated the latter as the best option. In dense regeneration areas, preferential treatment of the taller and larger stump‐sized seedlings and, in limited regeneration areas that of smaller seedlings, may yield better results. Additionally, removal of competing vegetation and canopy opening may also help establishment of young regeneration. The results of this study have applications for restoration of endangered species in other tropical dry deciduous ecosystems worldwide.     

授粉处理对红富士苹果果实品质影响的综合评价

以“长富2号”红富士苹果(Malus domestica ‘Red Fuji',Nagafu No. 2)为母本,9个授粉品种为父本,进行人工授粉,研究授粉处理对红富士苹果成熟期果实品质的影响,并构建基于主成分分析的综合评价函数。结果表明:果实的花青苷、单果重、维生素C、固酸比、可溶性糖、可溶性蛋白、可滴定酸等主要经济性状,各授粉处理间差异较大,果形指数、硬度差异较小; 主成分分析提取6个主成分,累计方差贡献率达96.02%,根据主成分得分和方差相对贡献率构建综合评价函数,由综合评价函数确定9个授粉处理果实的综合品质由高到低的排序为雪球、美红、火焰、红星、道格、全家红、绚丽、荷红、粉芽。     

Climatic effects in Central Europe on the frequency of medical treatments of dairy cows

In the present study, the relationship between the temperature–humidity index (THI) and the incidence of medical treatments in lactating dairy cows in Lower Saxony, Germany, was investigated. Records of all veterinary-treated cases over 2 years (2003 and 2005) from eight Holstein–Friesian dairy herds raised in loose-housing systems (55 to 170 cows per herd) were evaluated. After exclusion of management-dependent and climate-independent cases, a total of 5547 treatments were analyzed. Treatments were clustered into the following groups: metabolism, fertility, udder and foot/leg. Meteorological data were compiled from the nearest weather station (average distance ± s.d. 39 ± 13 km). Hourly temperatures and relative humidity values were used to calculate the THI, which was divided into classes. Out of the total number of treatments, 37.4%, 32.9%, 21.6% and 8.1% belonged to metabolism, udder, fertility and foot/leg, respectively. Data were analyzed with a mixed model that included THI class, season and year as fixed effects and farm as random effect. In general, incidences were neither affected by the year (P > 0.05) and season (P > 0.05) nor by THI classes (P > 0.05). In tendency, incidences of metabolic treatments increased with increasing THI and incidences of udder treatments increased with decreasing THI. In conclusion, indications of moderate heat stress during summer months in Central Europe were found in the present study, although THI and season did not affect the different disease complexes significantly.     

晚期肝癌和复发性肝癌治疗的研究进展

肝细胞癌(HCC)是我国最常见的恶性肿瘤之一,70%继发于肝炎、肝硬变。虽然诊断技术的提高,使肝癌的早期发现成为可能,然而由于肝癌早期症状隐匿,大多数肝癌确诊时已处于中晚期。肝切除术是治疗肝细胞癌最常用的手段。对于一些不可切除的晚期肝细胞癌,可采用动脉化疗栓塞以及系统化疗等手段使肿瘤降期,当转变成可切除肝癌后,再行补救性肝切除延长患者的生存期。此外,对于剩余肝体积不足而无法行一期肝切除的患者,可以采用PVE、ALPPS等方法,在剩余肝脏体积增大后再行二期肝切除术。肝内肿瘤复发率高也是导致肝细胞癌预后差的重要因素。在局部治疗后,建议在保留肝功能的前提下重复治疗。相比局部消融和动脉化疗栓塞治疗等多种手段,肝切除术有最好的远期疗效。联合和重复不同的治疗手段可达到很好的总生存期。对于患有晚期不可切除肿瘤或复发癌的患者,应积极的发挥肝切除的作用,并联合其他非手术治疗手段以取得较好的预后。