Exclusion of deceased donors post-procurement of tissues

The EU Tissues and Cells Directive (2004/23/EC, 2006/17/EC, 2006/86/EC) (EUTCD) provides standards for quality and safety for all aspects of banking of tissues and cells for clinical applications. Commission Directive 2006/17/EC stipulates that the complete donor record with all the medical information is assessed for suitability before releasing tissues for clinical use. The aim of this study was to investigate the medical reasons for post-procurement donor exclusion, to identify the various potential sources for gathering information about donors’ medical and behavioural history and to evaluate their contribution to maximising the safety of donations. Information was collected from the Tissue Services (TS) records of 1000 consecutive deceased donors submitted to National Health Service Blood and Transplant (NHSBT) medical officers for authorisation for release for subsequent tissue processing and then for transplantation. Of the 1000 donors 60 (6%) were excluded because they did not fulfil the donor selection requirements of the EUTCD and NHSBT donor selection guidelines. The main reasons for medical exclusion were the presence of significant local or systemic infection in 32 donors (53% of those excluded for medical reasons) and a history of past or occult malignancy in 9 donors (15% of those excluded for medical reasons) which was not identified prior to procurement. The information leading to post-procurement exclusion was obtained from autopsy reports in 35 of the 60 excluded donors for medical reasons (58%) and from the general practitioner for 10 donors (17% of those excluded for medical reasons). In summary, careful evaluation of complete donor records reduces the potential risk of disease transmission by tissue allografts and ensures compliance with regulations and guidelines. The findings may lead to changes in donor selection policies with the aim of improving efficiency without compromising safety.     

Effect of transportation temperature on the quality of cauda epididymal spermatozoa of ram

The objective of this study was to develop a protocol for ram epididymal sperm preservation that could be applied to wild ruminants for collection and preservation of spermatozoa from dead or hunted animals. Ram testicles collected from abattoirs were used to study the effect of two transportation temperatures viz. ambient temperature (AT) and refrigeration temperature (RT) on the cauda epididymal sperm quality at recovery and during preservation up to 72h at 4°C. For AT the testicles were transported in normal saline in a container (17.9-21.5°C) where as for RT the testicles were transported in an ice-chest (4.9-6°C). The results of the current study revealed that intact acrosome was significantly higher (P<0.01) and other quality parameters like sperm motility, live sperm count, sperm concentration and major sperm abnormalities were also higher (P>0.05) for RT than AT. The mean percent sperm motility for RT and AT was 81.67% and 78.33%, respectively. The corresponding figures were 92.08% and 90.46% for mean live sperm, 98.33% and 90.50% for intact acrosome, 0.50% and 0.33% for major sperm defects. The percent minor abnormality was 79.50% for RT and 77.67% for AT. The most prevalent minor defect was distal cytoplasmic droplet (70-80%). The mean sperm motility for RT and AT at 0h was 82.50% and 75.00%, respectively and the corresponding values at 72h of preservation were 60.00% and 45.83%. The mean live sperm at 0h for RT and AT were 92.92% and 88.92%, respectively and the corresponding figures at 72h were 81.50% and 73.17%. The mean intact acrosome at 0h for RT and AT was 98.58% and 90.58%, respectively and at 72h the corresponding values were 91.66% and 82.25%. The sperm motility, live sperm count and intact acrosome decreased significantly (P<0.05) from 0h to 72h of preservation for both transportation temperatures. The sperm motility, live sperm count and intact acrosome also varied significantly between the transportation temperatures. The major sperm abnormality for both RT and AT at each hour of preservation up to 72h was less than 0.5%. The study concluded that epididymides or testicles should be transported to the laboratory at RT (4.9-6°C) either in an ice-chest or portable refrigerator for their processing, evaluation and storage.     

眼科手术等候期患者家属对健康教育需求的调查

目的:了解眼科手术等候期患者家属对健康教育的需求。方法:采用自行设计的调查问卷对100名在患者手术过程中等候的家属进行调查。调查内容包括手术等候中希望获得的相关信息及其需求程度,需要的健康教育方式及每种健康教育的需求程度。结果:1).眼科手术等候中,家属强烈需要的信息有手术效果(76%)、术后饮食指导(60.4%)、手术费用(57.3%)、患者目前病情(54.2%)、术后头位指导(51%)。2).最需要的健康教育方式是与医生护士交谈(66%)。结论:对手术等候期的患者家属应根据需求实施科学有效的健康教育,用恰当的方式及时提供家属想要了解的信息,使他们具有良好的应对能力和心理承受能力,在照顾患者的过程中为患者提供有效的支持系统。     

Analysis of gene function of bacteriophage phi 29 of Bacillus subtilis: identification of cistrons essential for viral assembly.

Restrictive infection of Bacillus subtilis by suppressor-sensitive (sus) mutants of phi 29 has been used to search for cistrons that function in viral assembly. The products of cistrons 7, 9, 10, and 16 are necessary for head morphogenesis. The neck upper collar protein P10 and the tail protein P9 must be present for DNA packaging to occur. The protein P7 must be present for phage-related particles to form. A prohead-like particle has been isolated during 16-restrictive infection. The particle is composed of the proteins Hd, P10, F, and P7. P16 must function for DNA-filled particles to accumulate. A DNA-containing particle produced in the absence of the cistron 11 product may be an intermediate in the phi 29 assembly pathway. The protein P13 interacts with P9 and P11 to form a stable DNA-filled particle. The products of cistrons 2 and 3 are essential for viral DNA synthesis, and in their absence virus-related particles are not detected.     

Comparison of the effectiveness of the interaction of ribo- and deoxyriboprimers with DNA-polymerase from the human placenta

The Km and Vmax values for primers d(pA)n, d(pT)n, r(pA)n, r(pU)n where n = 1-16, were compared. The Km values for minimal primers dTMP, dAMP, rUMP, rAMP were found to be 48, 71, 602 and 602 microM, respectively. The Vmax value for any NMP made up approximately 7% of that for (pN)10. The lengthening of any primer per one mononucleotide unit for n from 1 to 10 resulted in the decrease of the Km value 1.8-fold and the increase of the Vmax value 1.35-fold. The ratios of the Km values for primers r(pA)n-d(pA)n and r(pU)n-d(pT)n were 7.5 and 12.5, respectively, for any n. The Km value for [d[pT)8]r(pU) primer was the same as for r(pU)9, but not for d(pT)9. Decanucleotide [d(Tp)9]ddT interacted with the polymerase competitively to the template, but not to the primer. The primer's 3'-OH group was supposed to form the hydrogen bond with the enzyme. The absence of 3'-hydroxygroup in [d(Tp)9]ddT resulted in its inability to compete effectively with the primer. The difference of the affinity of ribo- and deoxyriboprimers is due, apparently, to the existence of the different conformation of the furanose rings in the ribose and deoxyribose.     

Some aspects of the analysis of hand-wrist bone-age readings

Principal components analysis was applied to the individual center bone-age readings from the study outlined by Sproul and Peritz ('71) in the preceding paper. The first two components are amenable to a simple interpretation. The first one is a general skeletal maturity factor, which can be expressed as a weighted mean bone-age, with slightly higher weights attached to the metacarpals and phalanges II to V than to the other bone centers. The second component is a measure of the contrast between hand-bone and finger-bone ages, with generally high positive weights for the bone-ages of radius and carpals, low weights for metacarpals and negative weights for phalanges. The weights for the first component vary little between races and sexes or with children's height. The weights for the second component are less homogeneous. The first component accounts for some two thirds of the variability; the second component accounts for roughly nine percent of it. Mean values for the first two components vary considerably with the children's height. Various other results relating the first two components to height and parents' height are presented. An analysis of the correlation matrices of individual center bone ages revealed particularly high correlations (0.8 to 0.9) within rows, with the exception of thumb bone centers.     

Evaluation of the rate constants of sugar transport through maltoporin (LamB) of Escherichia coli from the sugar-induced current noise

LamB (maltoporin) of Escherichia coli outer membrane was reconstituted into artificial lipid bilayer membranes. The channel contains a binding site for sugars and is blocked for ions when the site is occupied by a sugar. The on and off reactions of sugar binding cause an increase of the noise of the current through the channel. The sugar-induced current noise of maltoporin was used for the evaluation of the sugar-binding kinetics for different sugars of the maltooligosaccharide series and for sucrose. The on rate constant for sugar binding was between 10(6) and 10(7) M-1.s-1 for the maltooligosaccharides and corresponds to the movement of the sugars from the aqueous phase to the central binding site. The off rate (corresponding to the release of the sugars from the channel) decreased with increasing number of glucose residues in the maltooligosaccharides from approximately 2,000 s-1 for maltotriose to 180 s-1 for maltoheptaose. The kinetics for sucrose movement was considerably slower. The activation energies of the stability constant and of the rate constants for sugar binding were evaluated from noise experiments at different temperatures. The role of LamB in the transport of maltooligosaccharides across the outer membrane is discussed.     

Reaction-kinetic parameters of glycidamide as determinants of mutagenic potency

Values for reaction-kinetic parameters of electrophiles can be used to predict mutagenic potency. One approach employs the Swain-Scott relationship for comparative kinetic studies of electrophilic agents reacting with nucleophiles. In this way glycidamide (GA), the putatively mutagenic/carcinogenic metabolite of acrylamide, was assessed by determining the rates of reaction with different nucleophiles. The rate constants (kNu) were determined using the "supernucleophile" cob(I)alamin [Cbl(I)] as an analytical tool. The Swain-Scott parameters for GA were compared with those of ethylene oxide (EO). The substrate constants, s values, for GA and for EO were found to be 1.0 and 0.93, respectively. The reaction rates at low values of nucleophilic strength (n=1-3), corresponding to oxygens in DNA, were determined to be 2-3.5 times higher for GA compared to EO. GA was also more reactive than EO towards other nucleophiles (n=0-6.4). The mutagenic potency of GA was determined in Chinese hamster ovary cells (hprt mutations in CHO-AA8 cells per dose unit with gamma-radiation as reference standard). The potency of GA was estimated to be about three mutations per 10(5) cells and mMh corresponding to about 40 rad-equ./mMh. A preliminary comparison of the mutagenic potency (per mMh and as rad-equivalents) of GA and EO shows an approximately seven times higher potency for GA. A higher mutagenic potency of GA compared to EO is compatible with expectation from reaction-kinetic data of the two compounds. The data confirmed that GA is not a strong mutagen, which is in line with what is expected for simple oxiranes. The present study shows the value of cob(I)alamin for the determination of reaction-kinetic parameters and their use for prediction of mutagenic potency.     

Effect of Temperature on the Embryogenesis of Geographic Populations of Rotylenchulus reniformis

The effect of temperature on the embryonic development of three populations of reniform nematode (Rotylenchulus reniformis) from the southeastern United States was studied. The development of eggs from single-cell stage to eclosion of second-stage juvenile was monitored at 20, 25, 30, and 35°C. All populations completed embryogenesis in 7 days at 25°C. The greatest differences among populations in time to completion of embryogenesis were observed at 20 and 35°C. Results at the intermediate temperatures (25 and 30°C) were similar for the three populations. The optimal temperature for embryogenesis was calculated to be 31.4°C for the population from Alabama, 28.4°C for the one from Mississippi, and 37.5°C for the one from South Carolina.     

Dissecting the domain structure of the regulatory subunit of cAMP-dependent protein kinase I and elucidating the role of MgATP

A truncated regulatory subunit of cAMP-dependent protein kinase I was constructed which contained deletions at both the carboxyl terminus and at the amino terminus. The entire carboxyl-terminal cAMP-binding domain was deleted as well as the first 92 residues up to the hinge region. This monomeric truncated protein still forms a complex with the catalytic subunit, and activation of this complex is mediated by cAMP. The affinity of this mutant holoenzyme for cAMP and its activation by cAMP are nearly identical to holoenzyme formed with a regulatory subunit having only the carboxyl-terminal deletion and very similar to native holoenzyme. The off rate for cAMP from both mutant regulatory subunits, however, is monophasic and very fast relative to the biphasic off rate seen for the native regulatory subunit. The effects of NaCl, urea, and pH on cAMP binding are also very similar for the mutant and native holoenzymes. Like the native type I holoenzyme, both mutant holoenzymes bind ATP with a high affinity. The positive cooperativity seen for MgATP binding to the native holoenzyme, however, is abolished in the double deletion mutant. The Hill coefficient for ATP binding to this mutant holoenzyme is 1.0 in contrast to 1.6 for the native holoenzyme. The Kd (cAMP) is increased by approximately 1 order of magnitude for both mutant forms of the holoenzyme in the presence of MgATP. A similar shift is seen for the native holoenzyme. Further characterization of the MgATP-binding properties of the wild-type holoenzyme indicates that a binary complex containing catalytic subunit and MgATP is required, in particular, for reassociation with the cAMP-bound regulatory subunit. This binary complex is required for rapid dissociation of the bound cAMP and is probably responsible for the observed reduction in cAMP-binding affinity for the type I holoenzyme in the presence of MgATP.     

A climatic stratification of the environment of Europe

Aim To produce a statistical stratification of the European environment, suitable for stratified random sampling of ecological resources, the selection of sites for representative studies across the continent, and to provide strata for modelling exercises and reporting. Location A ‘Greater European Window’ with the following boundaries: 11° W, 32° E, 34° N, 72° N. Methods Twenty of the most relevant available environmental variables were selected, based on experience from previous studies. Principal components analysis (PCA) was used to explain 88% of the variation into three dimensions, which were subsequently clustered using an ISODATA clustering routine. The mean first principal component values of the classification variables were used to aggregate the strata into Environmental Zones and to provide a basis for consistent nomenclature. Results The Environmental Stratification of Europe (EnS) consists of 84 strata, which have been aggregated into 13 Environmental Zones. The stratification has a 1 km² resolution. Aggregations of the strata have been compared to other European classifications using the Kappa statistic, and show ‘good’ comparisons. The individual strata have been described using data from available environmental databases. The EnS is available for noncommercial use by applying to the corresponding author. Main conclusions The Environmental Stratification of Europe has been constructed using tried and tested statistical procedures. It forms an appropriate stratification for stratified random sampling of ecological resources, the selection of sites for representative studies across the continent and for the provision of strata for modelling exercises and reporting at the European scale.     

Formulation Development of Parenteral Phospholipid-based Microemulsion of Etoposide

The aim of the present study was to investigate the potential of a phospholipid-based microemulsion formulation for parenteral delivery of anticancer drug, etoposide. The microemulsion area was identified by constructing pseudoternary phase diagrams. The prepared microemulsions were subjected to different thermodynamic stability tests. The microemulsion formulations that passed thermodynamic stability tests were characterized for optical birefringence, droplet size, viscosity measurement, and pH measurements. To assess the safety of the formulations for parenteral delivery, the formulation was subjected to compatibility studies with various intravenous infusions and in vitro erythrocyte toxicity study. The developed formulation was found to be robust and safe for parenteral delivery.     

The temperature dependence of the binding of 5 alpha-dihydrotestosterone, testosterone and estradiol to the sex hormone globulin (SHBG) of human plasma

The binding of 5 alpha-dihydrotestosterone (DHT), testosterone and estradiol to the sex hormone binding globulin (SHBG) and albumin in human plasma has been studied at 4, 20 and 37 degrees C using the method of equilibrium partition in an aqueous two-phase system based on dextran, poly(ethylene glycol) and water. The intrinsic association constants for the binding to SHBG and the apparent association constant for the binding to albumin have been determined from Scatchard-type binding plots. The affinity of SHBG for DHT is 1.2-1.3 times higher than that for testosterone and 4 times higher than that for estradiol. The affinity of SHBG for the steroids decreases with increasing temperature. The mean values of the free energy of binding, delta G degree, in the temperature range used are -52.3, -51.7 and -48.9 kJ X mol-1 for the binding of DHT, testosterone and estradiol, respectively, to SHBG. The corresponding values of the enthalpy change, delta H degree, are 73.7, 70.0 and 99.0 J X mol-1 X K-1. These values are discussed in terms of the difference in the structure of the steroids. The affinity of albumin for testosterone and estradiol is almost equal and is lower than that for DHT. The delta G degree for the binding to albumin is about 55% lower than that for the binding to SHBG.     

Metabolic engineering of the initial stages of xylose catabolism in yeasts for construction of efficient producers of ethanol from lignocelluloses

Plant biomass possesses a huge potential as a source for biofuel production. The main components of biomass are glucose and five-carbon sugar xylose. The yeast Saccharomyces cerevisiae that is used for industrial ethanol production from glucose is unable to xylose fermentation. Therefore a microorganism capable for efficient fermentation of both glucose and xylose has to be found in nature or constructed for economically feasible biomass conversion to ethanol. The active xylose fermentation could be performed by increasing the efficiency of initial stages of xylose metabolism. In this review the enzymes of initial stages of xylose metabolism in yeasts (xylose reductase, xylitol dehydrogenase, xylulokinase) and bacteria (xylose isomerase and xylulokinase) are characterized. The ways for construction of yeast strains capable of efficient alcoholic xylose fermentation are discussed.     

Development of a Fast, Reproducible and Effective Method for the Extraction and Quantification of Proteins of Micro-algae

The best method that was developed to extract protein from Chlorella was by sonic disruption of the cells for 3 cycles of 1 min. at 70W on ice in the presence of 1% (w/v) SDS. The best method to quantify the amount of protein in algal extracts is the staining method with the dye bicinchoninic acid. The developed method is reliable for the tested fresh-water micro-alga Chlorella, is also acceptable for the fresh-water micro-alga Chlamydomonas, but is not reliable for the marine micro-algae Dunaliella, Rhodomonas and Synechococcus. The extraction method was the most critical factor factor for determination of proteins in micro-algae and needs to be optimized for each algal species.     

Analysis of the self-association of human red cell spectrin

The self-association equilibrium of spectrin has been studied by separating the molecular species present in the cooled reaction mixture by gel electrophoresis. The association constant for formation of the hexamer from dimer and tetramer is lower by an order of magnitude than that for the association of two dimers. The association constant for the formation of the octamer from the hexamer is appreciably larger, and the value appears to reach a constant level for higher oligomers. These observations are explained in terms of conformational strain due to formation of cyclic structures, the distortion being greatest on passing from the tetramer to the hexamer. The association for a single-site interaction between the dimer and a univalent fragment has also been analyzed. The results show that the free energy generated by a single-point interaction is much greater than that obtained by averaging over all pairwise interactions within the oligomers, correcting for the effect of cratic entropy. The results are related to the association state of the spectrin prevailing in the cell. Phosphorylation at the physiological sites in the dimer does not appreciably change the thermodynamics of self-association, at least up to the hexamer.     

新城疫液相芯片快速检测方法的建立

目的：建立可检测新城疫病毒（Newcastle disease virus,NDV）的液相芯片快速检测技术。方法：用DNAStar软件对GEN-BANK中NDV的NP基因进行序列分析设计NDV特异性探针并标记生物素,利用该探针与荧光编码微球偶联后与抽提的NDV病毒RNA的RT-PCR产物杂交反应,用液相芯片检测仪（Liquichip 200）检测荧光信号建立了NDV快速液相芯片检测方法。结果：检测结果显示,该法具有较好的特异性,不与H5AIV和H9AIV反应;检测灵敏度达到150个EID50;该法与鸡胚病毒分离法检出NDV的符合率达到97.1%。结论：初步建立了检测NDV的液相芯片技术,为进一步搭建NDV全新快速高通量检测平台奠定了基础,也为其他同类病毒的快速高通量检测提供了借鉴和经验。     

Area of discovery of an insect parasite

It is assumed that insect parasites, searching for hosts, tend to avoid territorial interference as a functional response to others of their kind. The incorporation of this assumption into two models leads to density-dependent expressions for the area of discovery of the parasite species. The importance of this response for the stability of some ecological systems and for biological control programs is noted.     

Suitability of medium-range predictions of classical meteorological parameters and of the duration of leaf wetness for biometeorological forecasts

A classification of daily weather types is used to obtain typical deviations of daily maximum and minimum air temperatures, global radiation, amount of precipitation, mean daily relative humidity at 1400 hours local time, meteorological water balance, grass minimum temperature at a height above the turf of 5 cm and duration of daily leaf wetness for SW Germany (Stuttgart area) from the corresponding monthly means. The period of reference was the growing season from May to September for the 5 years 1980–1984. Medium-range weather forecast maps for the ground surface and the 850 hPa level are issued daily for 5 days in advance by the medium-range weather forecasting centre at Reading (ECMWF). The forecasts are valid for Western Europe and have been used to transform the forecasted flow pattern and air pressure distribution, both on the ground and at the 850 hPa level into Central European weather types, following the classification mentioned above. The seasonal variability (from May to September) has been found to be small enough to be able to present the results as a single table for the whole vegetation period. The deviation of the forecasted values from the observed values are compared, using as test period the 1988 and 1989 seasons. The forecasts were: (i) persistency forecasts (the same deviations are forecasted for the next 5-days period); (ii) supposed weather types during the next 5 days, derived from ECMWF with expected deviations of the meteorological elements from the seasonal mean; and (iii) real weather types, classified officially from the German Weather Service using mean deviations of the meterological elements from the seasonal means. The means obtained on the 5-day deviations are discussed. The values were, for exemple, 2 K for minimum temperature, about 3 K for maximum temperature, 20% of the values for global radiation, 1.5 mm for the amount of daily precipitation and 16% for the daily duration of leaf wetness. The mean relative deviations differed between the various meterological elements, being smaller for elements mainly related on the macro-/mesoscale than for elements such as minimum temperatures that are mainly related to the microclimate.