Cellular aggregate size as the critical factor for flavonoid production by suspension cultures of <Emphasis Type="Italic">Saussurea medusa</Emphasis>

Three previously established cell lines (yellow, red and white) of Saussurea medusa were investigated for jaceosidin and hispidulin production. Maximum yields of the jaceosidin and hispidulin were obtained in the red cell line at 75 ± 0.41 and 6.4 ± 0.31 mg l^-1. Production of jaceosidin and hispidulin correlated with the sizes of compact callus aggregates (CCA) and cellular viability. In the red cell line, the sizes of CCA were predominantly of 2–4mm diameter and accounted for 64% biomass. This line had a sustained cell viability over 10 successive sub-cultures.Revisions requested 3 September 2004/27 October 2004; Revisions received 22 October 2004/18 November 2004     

Re-use of shallow sediment patches by Pacific sand lance (<Emphasis Type="Italic">Ammodytes hexapterus</Emphasis>) in Barkley Sound,British Columbia,Canada

We determined whether, during the summers of 2002–2004, young-of-the-year (YOY) Pacific sand lance (Ammodytes hexapterus) re-used patches of sediment in intertidal and shallow subtidal regions of Barkley Sound, British Columbia, Canada. We examined re-use weekly at a single sediment patch in 2003 and 2004 via mark-recapture methods, monthly by re-sampling 15 patches in 2002 and interannually by re-sampling 36 patches in all 3 years (2002–2004). The mark-recapture results showed that, within each summer, batch marked YOY sand lance re-used the same patch up to 8 weeks later. The re-sampling of 15 patches over 4 months in 2002 showed that YOY sand lance consistently occupied patches within a season. We found the greatest variability in sediment patch re-use at the interannual time scale with major fluctuations in occurrence and abundance during 2002–2004. The interannual variability in patch re-use is most likely linked to abundance rather than the local or regional environmental characteristics that we examined.     

Contribution of root respiration to soil respiration in a C3/C4 mixed grassland

The spatial and temporal variations of soil respiration were studied from May 2004 to June 2005 in a C₃/C₄ mixed grassland of Japan. The linear regression relationship between soil respiration and root biomass was used to determine the contribution of root respiration to soil respiration. The highest soil respiration rate of 11-54 Μmol m^-2 s^-1 was found in August 2004 and the lowest soil respiration rate of 4.99 Μmol m^-2 s^-1 was found in April 2005. Within-site variation was smaller than seasonal change in soil respiration. Root biomass varied from 0.71 kg m^-2 in August 2004 to 102 in May 2005. Within-site variation in root biomass was larger than seasonal variation. Root respiration rate was highest in August 2004 (5.7 Μmol m^-2 s^-1) and lowest in October 2004 (1.7 Μmol m^-2 s^-1). Microbial respiration rate was highest in August 2004 (5.8 Μmol m^-2 s^-1) and lowest in April 2005 (2.59 Μmol m^-2 s^-1). We estimated that the contribution of root respiration to soil respiration ranged from 31% in October to 51% in August of 2004, and from 45% to 49% from April to June 2005.     

A study of the adsorption of bacterial cells on porous materials

The paper presents experimental data on the adsorption of bacterial cells on porous materials.Translated from Mikrobiologiya, Vol. 73, No. 6, 2004, pp. 810–816.Original Russian Text Copyright © 2004 by Samonin, Elikova.     

Thermostable cellulases from <Emphasis Type="Italic">Streptomyces</Emphasis>sp.: scale-up production in a 50-l fermenter

Thermostable cellulase was produced by Streptomyces sp. T3-1 grown in a 50-l fermenter. Maximum cellulase activity was attained on the fourth day when agitation speeds and aeration rates were controlled at 300 rpm and 0.75 vvm, respectively. Maximum enzyme activities were: 148 IU CMCase ml^–1, 45 IU Avicelase ml^–1, and 137 IU -glucosidase ml^–1 with productivity of 326 IU l^–1 h^–1, which were 10--32% higher than the values obtained in shake-flask culturesRevisions requested 12 October 2004/1 November 2004; Received received 1 November 2004/14 December 2004     

The population trend of southern elephant seals (<Emphasis Type="Italic">Mirounga leonina</Emphasis> L.) at Macquarie Island (1952–2004)

Total numbers of adult female southern elephant seals (cows) breeding at Macquarie Island were determined for 19 of the 52 year period between 1952 and 2004. Totals for 1952–1987 (exc. 1959 and 1985) were estimated from the relationship between censuses of the isthmus study area and concurrent censuses for the whole island. Totals for 1987–2004 were obtained by direct census of the entire island in mid-October. Cow numbers decreased from a maximum of about 40,000 in the 1950s to a minimum of 18,300 in 2000, but then increased slightly to 19,200 in 2004. Nonlinear and post-hoc linear analysis of the count data identified 1999 as the year when the exponential rate of change (r) slowed from −1.4% per annum to near zero. The rate of change was not uniform for each census sub-area counted (1987–2004), suggesting that certain terrestrially based density-dependent mechanisms were influencing the annual distribution of cows.     

Effects of <Emphasis Type="Italic">N</Emphasis>- and <Emphasis Type="Italic">C</Emphasis>-terminal truncation of HP (2-20) from <Emphasis Type="Italic">Helicobacter pylori</Emphasis> ribosomal protein L1 (RPL1) on its anti-microbial activity

HP (2-20) [derived from the N-terminal region of Helicobacter pylori Ribosomal Protein L1 (RPL1)], a 19-mer peptide, possesses broad-spectrum anti-microbial activity. As the N- (residues 2–3) and C-terminal (residues 14–20) residues can be deleted without affecting antimicrobial activity, we have now determined the minimum chain length necessary for the retention of antimicrobial activity, and its mode of action. The N- (residues 2–3) and C-terminal (residues 17–20) truncated fragments [HP (4–16)] induce increased antibiotic activity against several bacterial strains without hemolysis. Flow cytometric analysis, scanning electron microscopy and fluorescence confocal microscopy revealed that HP (4–16) acted rapidly on the plasma membranes of the fungal cells in a salt- and energy-independent manner.Revisions requested 16 September 2004/1 November 2004; Revisions received 29 October 2004/8 December 2004     

Blooms of Pseudo-nitzschia and domoic acid in the San Pedro Channel and Los Angeles harbor areas of the Southern California Bight, 2003–2004

Abundances of Pseudo-nitzschia spp. and concentrations of particulate domoic acid (DA) were determined in the Southern California Bight (SCB) along the coasts of Los Angeles and Orange Counties during spring and summer of 2003 and 2004. At least 1500 km² were affected by a toxic event in May/June of 2003 when some of the highest particulate DA concentrations reported for US coastal waters were measured inside the Los Angeles harbor (12.7 μg DA L⁻¹). Particulate DA levels were an order of magnitude lower in spring of 2004 (February and March), but DA concentrations per cell at several sampling stations during 2004 exceeded previously reported maxima for natural populations of Pseudo-nitzschia (mean = 24 pg DA cell⁻¹, range = 0–117 pg DA cell⁻¹). Pseudo-nitzschia australis dominated the Pseudo-nitzschia assemblage in spring 2004. Overall, DA-poisoning was implicated in >1400 mammal stranding incidents within the SCB during 2003 and 2004. Ancillary physical and chemical data obtained during our regional surveys in 2004 revealed that Pseudo-nitzschia abundances, particulate DA and cellular DA concentrations were inversely correlated with concentrations of silicic acid, nitrogen and phosphate, and to specific nutrient ratios. Particulate DA was detected in sediment traps deployed at 550 and 800 m depth during spring of 2004 (0.29–7.6 μg DA (g sediment dry weight)⁻¹). The highest DA concentration in the traps was measured within 1 week of dramatic decreases in the abundances of Pseudo-nitzschia in surface waters. To our knowledge these are the deepest sediment trap collections from which DA has been detected. Sinking of the spring Pseudo-nitzschia bloom may constitute a potentially important link between DA production in surface waters and benthic communities in the coastal ocean near Los Angeles. Our study indicates that toxic blooms of Pseudo-nitzschia are a recurring phenomenon along one of the most densely populated coastal stretches of the SCB and that the severity and magnitude of these events can be comparable to or greater than these events in other geographical regions affected by domoic acid.     

Mediated electrochemical measurement of the inhibitory effects of furfural and acetic acid on <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> and <Emphasis Type="Italic">Candida shehatae</Emphasis>

The toxic effects of furfural and acetic acid on two yeasts, Saccharomyces cerevisiae and Candida shehatae, were evaluated using an electrochemical method. Intracellular redox activities were lowered by 40% and 78% for S. cerevisiae and C. shehatae, respectively, by 8 g furfural l^–1, and by 46% and 67%, respectively, by 8 g acetic acid l^–1. The proposed method can accurately measure the effects of inhibitors on cell cultures.Revisions requested 27 September 2004/17 November 2004; Revisions received 15 November 2004/10 December 2004     

High groundwater nitrate concentrations inhibit eutrophication of sulphate-rich freshwater wetlands

During the last 60 years, pollution of the groundwater with has greatly increased in many parts of Europe, as a consequence of excessive use of manure and synthetic fertilisers. Monitoring of groundwater-fed wetlands indicated that sediments with high concentrations had the lowest Fe and concentrations in the pore water. A comparison of two restored open water fens, differing in supply via the groundwater, indicated that the redox potential and the sulphate ( ) reduction rate were lower when the groundwater contained not only but also high concentrations. The lower reduction rates in the -rich open water fen were associated with lower concentrations and the presence of plant species characteristic of clear water. In contrast, the higher reduction rates in the -poor open water fen were associated with very high concentrations and massive development of plant species characteristic of eutrophic environments. Investigations at -rich seepage sites in black alder carrs, showed that high concentrations in the pore water caused chlorosis in the alder carr vegetation, due to lower availability of Fe in the pore water and less Fe uptake by the plants. Experimental desiccation of sediments proved that the -rich seepage sites contained no oxidisable FeS _x , contrary to -poor locations, which became acidified and mobilised extremely high amounts of due to FeS _x oxidation. A laboratory experiment showed that addition to sediments led to reduced releases of Fe, and S^2–, very likely due to the oxidation of reduced Fe and S compounds. Overall, the results confirmed that is an energetically more favourable electron acceptor in anaerobic sediments than Fe and , and that high loads function as a redox buffer, preventing reduction of Fe and . Limited reduction prevents S^2– -mediated mobilisation of from Fe- complexes. At a higher redox potential, reduced Fe, including FeS _x , was oxidised, increasing the content of Fe(III) capable of binding . This prevented increased availability and the concomitant massive development of plant species characteristic of eutrophic environments.     

Linkage analysis using multiple DNA polymorphic markers in normal families and in families with fragile X syndrome

Summary Linkage data, using the polymorphic markers 52A (DXS51), F9, 4D-8(DXS98), and St14(DXS52), are presented from 14 fragile X pedigrees and from 7 normal pedigrees derived from the collection of the Centre d'Étude du Polymorphisme Humaine. A multipoint linkage analysis indicates that the most probable order of these four loci in normal families is DXS51-F9-DXS98-DXS52. Recombination frequencies ( ) corresponding to maximum LOD scores ( ) were obtained by two-point linkage analysis for a nuber of linkage groups, including: DXS51-F9 ( =5.94, =0.03), F9-DXS98 ( =0.51, =0.26), F9-DXS52 ( =0.84, =0.27), and DXS98-DXS52 ( =0.32, =0.20). A multipoint linkage analysis of these loci, including the fragile X locus, was also performed for the fragile X population and the data support the relative order (DSX51, F9, DXS98)-FRAXA-DXS52. Recombination frequencies and maximum LOD scores, which again were derived from two-point linkage analyses, were obtained for the linkage groups DXS51-F9 ( =9.96, =0) and F9-DXS52 ( =0.07, =0.45), as well as for the groups DXS51-FRAXA ( =2.42, =0.15), F9-FRAXA ( =1.30, =0.18), DXS98-FRAXA ( =0.05 =0.36), and DXS52-FRAXA ( =2.42 =0.15). The linkage data was further tested for the presence of genetic heterogeneity both within and between the fragile X and normal families for the intervals DXS51-F9, F9-DXS52, F9-FRAXA, and DXS52-FRAXA using a modification of the A test. Except for the interval F9-FRAXA (P<0.10) there was no evidence of genetic heterogeneity for each of the various linkage groups examined. The heterogeneity detected for the interval F9-FRAXA, however, was most likely due to one family (Fx-28) that displayed very tight linkage between these two loci.     

Temporal Trends in Treatment Outcomes for HIV-1 and HIV-2-Infected Adults Enrolled in C?te d'Ivoire's National Antiretroviral Therapy Program

Background

In Côte d''Ivoire during 2004–2007, numbers of ART enrollees increased from <5,000 to 36,943. Trends in nationally representative ART program outcomes have not yet been reported.

Methodology/Principal Findings

We conducted a retrospective chart review to assess trends in patient characteristics and attrition [death or loss to follow-up (LTFU)] over time, among a nationally representative sample of 3,682 adults (≥15 years) initiating ART during 2004–2007 at 34 health facilities. Among ART enrollees during 2004–2007, median age was 36, the proportion female was 67%, the proportion HIV-2-infected or dually HIV-1&2 reactive was 5%, and median baseline CD4⁺ T-cell (CD4) count was 135 cells/µL. Comparing cohorts initiating ART in 2004 with cohorts initiating ART in 2007, median baseline weight declined from 55 kg to 52 kg (p = 0.008) and the proportion weighing <45 kg increased from 17% to 22% (p = 0.014). During 2004–2007, pharmacy-based estimates of the percentage of new ART enrollees ≥95% adherent to ART declined from 74% to 60% (p = 0.026), and twelve-month retention declined from 86% to 69%, due to increases in 12-month mortality from 2%–4% and LTFU from 12%–28%. In univariate analysis, year of ART initiation was associated with increasing rates of both LTFU and mortality. Controlling for baseline CD4, weight, adherence, and other risk factors, year of ART initiation was still strongly associated with LTFU but not mortality. In multivariate analysis, weight <45 kg and adherence <95% remained strong predictors of LTFU and mortality.

Conclusions

During 2004–2007, increasing prevalence among ART enrollees of measured mortality risk factors, including weight <45 kg and ART adherence <95%, might explain increases in mortality over time. However, the association between later calendar year and increasing LTFU is not explained by risk factors evaluated in this analysis. Undocumented transfers, political instability, and patient dissatisfaction with crowded facilities might explain increasing LTFU.     

Chilling and heat requirements for the prediction of the beginning of the pollen season of Alnus glutinosa (L.) Gaertner in Ponferrada (León, Spain)

Winter-flowering trees such as the alder (Alnus glutinosa (L.) Gaertner) can survive periods of adverse climatic conditions, entering a period of dormancy in the early fall. The end of dormancy and the start of the pollen season require a period of low temperatures followed by another of warm temperatures. These requirements were studied from 1995 to 2002, in order to develop a model to predict the onset of the alder pollen season in Ponferrada (Spain). Chilling accumulation took place from late October to late December or early January. The best result was obtained with a threshold temperature of 6.5 °C and an average of 848 chilling hours (CH). Heat requirements were calculated at maximum temperature, an average 143 growth degree days (GDD) were needed, with a threshold temperature of 0 °C. In order to validate models, predicted values were compared with real values for 2002–2003, 2003–2004 and 2004–2005, years not used in developing the models. Predictions for the pollen-season start-date differed only slightly from observed dates: in 2002–2003 predicted and observed dates were the same, in 2003–2004 there was a difference of 7 days and in 2004–2005 a difference of 3 days.     

Online Medical Literature Consultation Habits of Academic Teaching Physicians in the EU and CIS Countries: A Cross-Sectional Study

Background

Both in the Commonwealth of Independent States (CIS) and in the European Union (EU2004), ample availability of up to date medical scientific literature is important for progress in medical science and for the education of the next generation of healthcare workers. The aim of this research is to assess if the use of online medical literature among academic teaching (AT) physicians is at the same level in the CIS as in the EU2004.

Methodology/Principal Findings

In the capital cities of the CIS and the EU2004 member states, AT physicians holding an academic position at least equivalent to an associate professor and performing the three classical tasks in academic medicine (teaching, research and patient care) were interviewed about their use of and familiarity with the Internet and 9 online literature services, including journals and bibliographical databases such as PubMed (Medline), The Cochrane Library and Web of Science. Library staff members were interviewed about the availability of these online literature services at their libraries. About 750 physicians and 40 library staff members were invited for participation. Eventually 124 AT physicians and 22 library staff members participated. Internet was everywhere available, but used daily by more AT physicians in the EU2004 (71% versus 48% in the CIS, P = .005). AT physicians in the EU2004 accessed a higher percentage of all articles online (74% versus 43% in the CIS, P<.001). PubMed (P<.001), The Cochrane Library (P<.001) and Web of Science (P<.003) were used more frequently in the EU2004. In the EU2004 more AT physicians were familiar with Open Access journals (89% versus 51% in the CIS, P<.001).

Conclusions/Significance

AT physicians in the CIS use online medical literature less than in the EU2004. It is recommended that the awareness of freely available online literature services such as Open Access journals is enhanced among AT physicians and library staff members, especially in the CIS.     

Respiration of the emersed shore crab at variable ambient oxygenation

Summary In the intertidal shore crab,Carcinus maenas, pH and values of the prebranchial venous hemolymph, and , the PO₂ values of the arterialized cardiac hemolymph, , were measured, and the ventilatory activity was assessed by measuring the hydrostatic pressures at the exits of the epibranchial cavities, under four environmental conditions: normoxic water, normoxic air, hypoxic gas, hyperoxic gas.In the crab breathing normoxic air, was lower and higher than in animals breathing normoxic water. With the switch to hypoxic gas, ventilation increased and and decreased. With the switch to hyperoxic gas, ventilation decreased, and increased and decreased.Thus these crabs breathing air were not as well oxygenated as when breathing air-equilibrated water, and because of their low , they were relatively hypervetilating and hypocapnic compared to air-breathing vertebrates. Hyperoxic breathing, increasing and reducing ventilatory drive, led to increased . Conversely, was reduced by hypoxic breathing. These observations suggest that the gas exchanger of intertidal crabs is not as successfully designed for air breathing as that of land-colonizing insects and air-breathing vertebrates.     

Activity and oxygen consumption during hypoxic exposure in high altitude and lowland sceloporine lizards

Summary Resting rates of O₂ consumption against , exercise endurance times and during recovery from vigorous exercise were measured inSceloporus occidentalis captured near sea level and inS. graciosus captured above 2850 m. Oxygen consumption against was also measured inS. occidentalis captured above 2850 m. When was recorded continuously, as ambient was slowly reduced from 155 Torr, it became directly dependent upon ambient between 110 and 120 Torr. The critical for the high altitude lizards was lower than that for the lowland lizards, which enabled the former to maintain relatively higher 's when ambient was reduced below 120 Torr. The high altitude lizards also had significantly greater endurance when stimulated to exercise at 1600 m ( 130 Torr). Both the higher under hypoxia and the greater endurance roughly parallel a significantly greater maximum in the high altitude lizards. At a simulated altitude of 3600 m ( 100 Torr), maximum and rate of recovery of the O₂ debt calculated from post active were significantly reduced in the lowland but not the high altitude lizards. The effects of simulated altitude conditions on the lowland but not the mountaine animals indicate adaptations to altitude in these sceloporine lizards. We did not find any consistent relationship between organ/body weight ratios or hematocrit and our measures of endurance or the altitude at which the lizards were captured.     

Aerobic and anaerobic contribution to Wingate test performance in sprint and middle-distance runners

We investigated the aerobic and anaerobic contributions to performance during the Wingate test in sprint and middle-distance runners and whether they were related to the peak aerobic and anaerobic performances determined by two commonly used tests: the force-velocity test and an incremental aerobic exercise test. A group of 14 male competitive runners participated: 7 sprinters, aged 20.7 (SEM 1.3) years, competing in 50, 100 and 200-m events and 7 middle-distance runners, aged 20.0 (SEM 1.0) years, competing in 800, 1,000 and 1,500 m-events. The oxygen uptake ( ) was recorded breath-by-breath during the test (30 s) and during the first 20 s of recovery. Blood samples for venous plasma lactate concentrations were drawn at rest before the start of the test and during the 20-min recovery period. During the Wingate test mean power ( ) was determined and three values of mechanical efficiency, one individual and two arbitrary, 16% and 25%, were used to calculate the contributions of work by aerobic ( _{aer,ind,16%,25%}) and anaerobic ( _{an,ind,16%,25%}) processes. Peak anaerobic power ( _an,peak) was estimated by the force-velocity test and maximal aerobic energy expenditure ( _aer,peak) was determined during an incremental aerobic exercise test. During the Wingate test, the middle-distance runners had a significantly greater than the sprinters (P < 0.001), who had significantly greater venous plasma lactate concentrations (P < 0.001). Moreover, _{aer,ind,16%,25%} were also significantly higher (P < 0.05) in the middle-distance runners [ _aer,ind 45 (SEM 4) % vs 28 (SEM 2) %; _aer,16% 30 (SEM 3) % vs 19 (SEM 2) %; _aer,25% 46 (SEM 3) % vs 29 (SEM 2)%]; _{an,ind,16%,25%} in the sprint runners (P < 0.05) [ _an,ind 72 (SEM 3) % vs 55 (SEM 4) %; _an,16% 81 (SEM 2) % vs 70 (SEM 3) %; _an,25% 71 (SEM 2) % vs 54 (SEM 3) %]. The _aer,ind/ _aer,peak and × _an,ind/ _an,peak ratios, however, were not significantly different between the two groups of athletes. These results would indicate that the sprinters and middle-distance runners used preferentially a metabolic system according to their speciality. Nevertheless, under the conditions of its experiment, they seemed to rely on the same percentage of both peak anaerobic and peak aerobic performance for a given exercise task.     

Biochemical problems of regulation by oligopeptides

Some problems are considered which arise in biochemical studies on structure and function of natural oligopeptides consisting of 2–50 amino acid residues. The problems under consideration include the generation of oligopeptides from precursors, chemical structure, the role of functionally important radicals and spatial configuration, and structure-function relationships. Different types of regulation are shown mainly for oligopeptides involved in muscle contraction.Translated from Biokhimiya, Vol. 69, No. 11, 2004, pp. 1565–1573.Original Russian Text Copyright © 2004 by Zamyatnin.