Determination of copper, manganese and zinc in human liver

Autopsied liver tissue samples collected from 42 males and 31 females were analyzed for copper, manganese and zinc using atomic absorption spectrometry (AAS). With the exception of two liver samples for which the copper levels were determined to be 74.8 and 104.0 g/g (dry weight), hepatic copper concentrations were found to range from 1.7 to 32.4 g/g with a mean concentration of 14.2 g/g and standard deviation of 7.0 g/g. Manganese concentrations (with the exception of one sample having 12.9 g/g) ranged from 0.22 to 4.6 g/g with a mean of 2.26 ± 1.00 g/g. Hepatic zinc levels averaged 118.3 ± 44.4 g/g and ranged from 38.5 to 231.3 g/g. There were no apparent trends for the levels of any metals versus age nor were there any differences in average hepatic metal concentrations for males and females. © Rapid Science 1998.     

Impact of lead exposure on pituitary-thyroid axis in humans

Thyroid function tests (serum levels of thyroxine-T4, triiodothyronine-T3 and thyroid stimulating hormone-TSH) were performed in fifty-eight men (mean age: 31.7±10.6 years; mean duration of lead exposure: 156.9±122.7 months). These subjects were exposed to lead either as petrol pump workers or automobile mechanics. The mean whole blood lead (Pb-B) levels were 2.49±0.45 mole/l (51.90±9.40 g/dl) in the lead exposed workers and were approximately 5 times higher than in the control (n=35) subjects. No significant alteration was seen in their mean T3 and T4 levels as compared with the controls. Interestingly, T3 was significantly lower with the longer (210 months) exposure time in comparison with the group having shorter (29 months) exposure duration. The mean TSH levels were significantly (p<0.01) higher in workers exposed in comparison with the control group. This rise in TSH was independent of exposure time, but it was definitely associated with the Pb-B levels. The increase being more pronounced with mean Pb-B levels of 2.66±0.2 mole/l (55.4±4.25 g/dl) when compared with the group having mean levels of 1.51±0.30 mole/l (31.5±6.20 g/dl). The rise is TSH associated with Pb-B levels was only statistical valid, however, the levels fall within the normal laboratory range. We thus conclude that the Pb-B levels of 2.4 mole/l (50 g/dl) could enhance the pituitary release of TSH without having any significant alterations in the circulating levels of T3 and T4.     

Method of isolation of cysteine constitutive mutants of the cysteine regulon in Salmonella typhimurium.

Summary Size and shape of mitochondrial DNA molecules of Schizosaccharomyces pombe were analyzed by electron microscopy. Besides numerous linear molecules, circular molecules ranging from 0.83 m to 12.81 m were found. Depending on the method of preparation, both closed and open circular molecules were found. Most of the circular molecules could be assigned to five major size classes of 0.83±0.05 m, 1.7±0.05 m, 4.74±0.04 m, 5.74±0.04 m, and 8.32±0.07 m. Possible explanations for the different size classes of mitochondrial DNA molecules are discussed.     

Lipid Peroxides are Generated by the Fetal Rat Brain After Episodes of Global Ischemia in Utero

Complete arrest of maternal-fetal blood supply for up to 30 min caused a time-dependent increase in the endogenous levels of lipid peroxides (LPO) in fetal brain and liver extracts and fetal blood and amniotic fluids as indicated by the appearance of thiobarbituric acid reactive substances (TBARS), A steady increase of TBARS from 48.0 ± 2.2 pmol/g wet weight to 75.0 ± 5.6 pmol/g wet weight up to 30 min restriction was noticed in the fetal brain. The fetal liver TBARS values increased by approximately 69% after 5 min restriction and remained high, above the control level, for 30 min. After two days reperfusion following 30 min restriction, the TBARS levels in the fetal brain were 1.8 fold higher above the control, while those of the liver returned to control values. The levels of the lipid-soluble antioxidant -tocopherol were reduced by about 40% and 50% in the placenta and brain tissues after 5 min restriction, respectively. Slices of fetal brain incubated at 37°C in DMEM under oxygen in the presence of 50 M Fe²⁺ were able to generate LPO in a time- and tissue concentration-dependent manner. After 15 min incubation, about 6.3 fold increase in total TBARS levels could be measured in the presence of 50 M Fe²⁺, most of which was released in the medium. The iron chelator desferrioxamine (25 M) and the antioxidant -tocopherol (10 M) added to the incubation medium, each inhibited by about 88% TBARS production. After 20 min episode of ischemia, fetal brain slices released into the medium 138.5 ± 9.8 nmol/15 min/mg DNA compared to 75.9 ± 4.5 nmol/15 min/mg DNA released by the sham preparations. After 3 h reperfusion, brain slices from fetuses exposed to 20 min ischemia continued to produce TBARS above control levels, whereas those of brief ischemia (5 min) returned to control levels. The data indicate that the limited resistance of the fetal brain to brief, rather than prolonged, periods of ischemia, is likely due to a lack of free FA for LPO generation, rather than the levels of tissue lipid antioxidants.     

Increased locus coeruleus glutamate levels are associated with naloxone-precipitate withdrawal from butorphanol in the rat

Extracellular fluid levels of glutamate were measured in the locus coeruleus during butorphanol (a mixed agonist at -, -, and -opioid receptors) withdrawal by using microdialysis in conscious butorphanol-dependent Sprague-Dawley rats. Guide cannulae were implanted chronically and rats were given intracerebroventricular (i.c.v.) infusions of butorphanol (26 nmol/l l/hr) or saline (1 l/hr) for 3 days. Microdialysis probes (2 mm tip) were inserted into the locus coeruleus 24 hr before precipitation of withdrawal by i.c.v. injection of naloxone (48 nmol/5 l). A separate series of rats was rendered dependent by peripheral injection of butorphanol (20 mg/kg, s.c., b.i.d.) for 5 days and naloxone (5 mg/kg, i.p.) was given to precipitate withdrawal. Single injections of butorphanol (26 nmol/5 l, i.c.v.) had no effect on the extracellular fluid levels of glutamate, compared to rats injected with vehicle. Behavioral evidence of withdrawal was detected following naloxone challenge in butorphanol-dependent rats (both i.c.v. and s.c. models), but not in nondependent, vehicle-treated rats. Significant increases (P<0.05) in levels of glutamate were noted after naloxone-precipitated withdrawal only in the butorphanol group. The glutamate levels in the locus coeruleus increased from 8.37±2.01 before, to 21.93±4.58 M in the first 15 min sample following i.c.v. injections of 48 nmol/5 l naloxone and from 10.84±1.74 before, to 26.01±6.19 M in the 15–30 min sample following i.p. injections of 5 mg/kg naloxone in the butorphanol-dependent rats, respectively. These results provide direct evidence to support the role of excitatory amino acids within the locus coeruleus in butorphanol withdrawal.     

Mercury distribution in estuarine environments from Argentina: the detoxification and recovery of salt marshes after 15 years

Total Hg contents from abiotic (surface sediments and suspendedparticulate matter) and biological (crabs, fishes and halophytes)compartments from Bahía Blanca estuary and Mar Chiquita CoastalLagoon, Argentina, have been monitored since the 1980's. At BahíaBlanca estuary, high Hg concentrations were recorded during the early1980's in surface sediments (0.34 ± 0.22 g/g) andsuspended particulate matter (0.19 ± 0.10 g/g). Fishspecies, Mustelus schmitti (0.89 ± 0.29 g/g), Paralichthys brasiliensis (0.85 ± 0.18 g/g) and Micropogonias furnieri (0.37 ± 0.11 g/g) also presentedhigh Hg concentrations. The large industrial nucleus located within theestuary has been identified as the main metal source for this environment.Hg contents from the same area during 1996–1998 were significantlylower: surface sediments (0.164 ± 0.023 g/g), suspendedparticulate matter (0.048 ± 0.0017 g/g), fish Micropogonias furnieri (0.13 ± 0.02 g/g) and crab Chasmagnathus granulata (0.334 ± 0.071 g/g). This trendof environmental detoxification is probably related with (i) thetechnological changes incorporated by the local industry, (ii) a mostadequate management of industrial effluents, and (iii) the removal ofgreat sediment volume by dredging and refill.During the 1980's Mar Chiquita Lagoon Hg concentrations reached 0.08± 0.01 g/g in surface sediments and 0.09 ±0.025 g/g in suspended particulate matter, and 0.14 ±0.04 g/g in the fish Basilichthys bonariensis and 0.22 ±0.08 g/g in Paralichthys brasiliensis, and 0.08 ±0.01 g/g in the crab C. granulata, Hg concentrations werelower than at Bahía Blanca. Remote Hg sources for this Coastal Lagoonand atmospheric and stream transport of Hg is proposed as major Hgsources, since no Hg point sources exists nearby. Mercury concentrationsrecorded in the 1996–1998 period were lower than those recorded inthe previous decade: surface sediments (0.019 ± 0.004 g/g), suspended particulate matter (0.030 ± 0.008 g/g), halophyte Spartina densiflora (0.013 ± 0.008 g/g) or crab C. granulata (0.011 ± 0.009 g/g).Both Hg bioaccumulation and biomagnification processes were verified inBahía Blanca estuary and in Mar Chiquita Coastal Lagoon. This apparentrecovery of both estuarine environments deserves to be carefully analyzed,in order to fully understand the foundations of these processes.     

Isolation of astaxanthin-overproducing mutants of Phaffia rhodozyma

We isolated mutants of Phaffia rhodozyma strain NRRL Y-17269 that overproduced astaxanthin when grown on corn-based fuel ethanol stillage (thin stillage, TS, or fuel ethanol byproducts). Ten ml cultures of mutant strain JB2 produced 1.54 ± 0.21 mg carotenoid/mg dry weight when grown on 70% thin stillage at pH 5.2, compared with 0.38 ± 0.04 g/mg produced by the parental strain. Furthermore, JB2 produced similar astaxanthin concentrations when grown in either thin stillage or yeast malt broth. By comparison, previously described astaxanthin overproducing strain NRRL Y-17811 yielded 1.08 ± 0.07 g/mg in yeast malt broth but only 0.67 ± 0.03 g/mg in thin stillage. Five liter fermentation experiments using JB2 grown on 70% thin stillage at pH 5.2 yielded 2.01 ± 0.17 g/mg astaxanthin. Thus, JB2 is uniquely suited for astaxanthin production from low cost thin stillage.     

Effects of GABA antagonists,SR 95531 and bicuculline,on GABAA receptor-regulated chloride flux in rat cortical synaptoneurosomes

Synaptoneurosomes isolated from cerebral cortices of male Sprague-Dawley rats were used for studying GABA_A receptor-regulated chloride influx. The in vitro effects of GABA antagonists, SR 95531 (a pyridazinyl GABA derivative) and bicuculline, on pentobarbital-stimulated, muscimol-stimulated or flunitrazepam-enhanced, muscimol-stimulated chloride uptake were studied. The chloride uptake was determined at 30°C, for 5 sec. Pentobarbital and muscimol produced a maximal stimulation of chloride uptake in cortical synaptoneurosomes at 500 M and 50M, respectively. SR 95531 as well as bicuculline had no effect on the basal uptake of chloride. Whereas, SR 95531 (0.3–30 M) and bicuculline (0.1–100 M), when added 5 min before muscimol (50 M), produced a significant concentration-dependent inhibition of muscimol (50 M)-stimulated chloride uptake (IC₅₀ s of 0.89±0.11 M and 13.45±2.10M, respectively). In studies of the inhibitory effects of SR 95531 and bicuculline on pentobarbital (500 M)-stimulated chloride uptake, the IC₅₀ s were 0.81±0.12 M and 3.86±1.14 M, respectively. SR 95531 exhibited a more potent inhibitory effect than bicuculline on flunitrazepam-enhanced, muscimol-stimulated chloride uptake. The results revealed that SR 95531 has a more potent antagonistic effect than bicuculline on GABA_A-regulated chloride flux.     

Enzyme,protein, and nucleic acid content of two morphological forms of Trypanosoma (Schizotrypanum) cruzi

Summary Trypanosoma (Schizotrypanum) cruzi (Corpus Christi strain) was cultivated at 28°C over a monolayer of African Green Monkey kidney cells (Vero line). The epimastigote was converted into the trypomastigote by serial passage of the organisms at 33°C in a modified culture system. This resulted in preparations containing better than 90% trypomastigotes.The biochemical composition of the epimastigotes and trypomastigotes was determined in whole cells and cell-free homogenates of organisms grown in these systems. The epimastigote contained 50±2 g of protein, 2.0±0.1 g of RNA, and 1.7±0.2 g of DNA per 10⁷ organisms; while the trypomastigote contained: 24±1 g of protein, 1.4±0.1 g of RNA, and 2.4±0.3 g of DNA per 10⁷ organisms. Data was also obtained on the specific activities of certain metabolically important enzymes. The following (in nmoles min^-1mg^-1 of protein) are given in the order; enzyme, epimastigote activity, trypomastigote activity: aspartic aminotransferase, 1058±139, 466±16; alanine aminotransferase, 1076±131, 474±27; aldolase, 172±8, 11±0.6; isocitric dehydrogenase (NADP-linked), 137±7, 58±4; malic dehydrogenase, 2270±116, 1073±93; glucose-6-phosphate dehydrogenase, 50±3, 115±16; 6-phosphogluconic acid dehydrogenase, 101±7, 30±2.These results were consistent with the hypothesis that the trypomastigote is an intermediate, resting form of T. (S.) cruzi possessing a reduced level of metabolic activity, especially with respect to carbohydrates. Differentation of the epimastigote into the trypomastigote form is accompanied by an adjustment of enzyme concentrations which reflect this reduction in metabolic activity.     

Mercury contamination in Lake Xolotlán (Managua)

Total mercury was measured in different compartments of Lake Xolotlán's (Managua) ecosystemviz., sediments, water, fish and men. Sediments from 18 localities at 5 depths inside the sediment (5, 10, 15, 20 and 25 cm) contained an average concentration of 0.62 g Hg.g^–1±0.46 at the surface, with extreme values of 0.16 and 1.8 g.g^–1. The highest concentration was observed at 25 cm depth in front of the chlor-alkaly factory (ELPESA). This maximum is associated with the period of highest production of this factory. The highest mercury concentrations in water were also measured close to the discharge of ELPESA,viz. 787 g.Hg^–1 in January and 506 g.g^–1 in April. The mean mercury concentrations measured in the muscles of the most consumed fish were 0.63 g.g^–1±0.22 (extreme values 0.22 and 1.45) inCichlasoma managuense, and 0.07 g.g^–1±0.14 (extreme values 0.004 and 0.63) inC. citrinellum. The concentration in the liver was 0.79 g.g^–1±1.29 inC. managuense and 0.62 g.g^–1±0.44 inC. citrinellum. Human hairs (n=98) of fishermen and their families contained 5.03 g.g^–1±6.2 (extreme values 0.02 and 38.22). The mean concentration measured in men was 6.22 g.g^–1±6.34 (n=58), and in women 3.39 g.g^–1±5.7 (n=40). The average mercury concentration of hairs of workers of ELPESA was 91.24 g.g^–1±156.9 (extreme values 0.46 and 724.53; n=32). We conclude that total mercury levels in the various ecosystem compartments are very high and mercury contamination in the lake may be considered as dangerous for human health.     

Functional analysis of actin fibrils in Physarum polycephalum

Summary Fluorochromed heavy meromyosin (TRITC-HMM) was microinjected as a molecular probe into small sandwich-plasmodia of Physarum polycephalum with the aim to demonstrate the spatial morphology and to analyze the dynamic activity of the fibrillar actin system in the living state. The plasmodia display different fibrillar organizations with a polygonal arrangement in the front region (FR) and a parallel or helical arrangement along protoplasmic veins in the intermediate (IR) and uroid region (UR). Quantitative evaluations by measuring the total length, lifetime, dynamic activity, long-term stability and optical density of fibrils reveal distinct differences between the three plasmodial regions: The total length (FR = 27.1 ± 18.5 m, IR = 24.8 ± 12.9 m, UR= 12.3 ± 4.7 m), the lifetime (FR = 12.2 ± 3.4 min, IR=10.5 ± 3.7 min, UR = 6.0 ± 3.4 min), and the dynamic activity as measured in length changes per min (FR = 17.9 ± 11.3 m, IR = 13.1 ± 3.9 m, UR = 8.3 ± 3.9 m) distinctly decrease from the front to the uroid region. On the other hand, the greatest stability as determined by lifetime changes in length (FR = -2.4 ± 16.2 m, IR = 0.3 ± 10.1 m, UR = -6.6 ± 8.9 m) and the highest optical density as expressed in grey-values (FR = 57.0 ± 14.1 gv, IR = 115.6 ± 26.1 gv, UR 62.5 ± 8.1 gv) were found for actomyosin fibrils of the intermediate region. The morphological and physiological data of the present paper are discussed with respect to the biological significance of the fibrillar microfilament system in Physarum polycephalum.     

The contribution of size-fractionated plankton to biomass and primary production of phytoplankton in saline–alkaline ponds

Primary productivity, biomass and chlorophyll-a of size fractionated phytoplankton (<0.22 m, <3 m, <8 m, <10 m, <40 m, <64 m, <112 m and <200 m) were estimated in 6 ponds and 5 experimental enclosures. The results showed that the planktonic algae less than 10 m are important in the biomass and production of phytoplankton in saline–alkaline ponds. The production of size fractionated phytoplankton corresponding to <112 m, <10 m and <3 m in saline–alkaline ponds were 10.5 ± 6.6 , 8.6 ± 5.4 and 0.33 ± 0.1 mgC l^–1 d^–1, respectively. Mean community respiration rate was 1.80 ± 0.73, 1.69 ± 0.90 and 1.38 ± 1.12 mgC l^–1 d^–1, respectively. The average production of phytoplankton corresponding to micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) were 1.61, 8.30 and 0.33 mgC l^–1 d^–1, respectively. The ratio of those to the total phytoplankton production was 15%, 79% and 3%, respectively. The mean respiration rate of the different size groups was 0.11, 0.31 and 1.38 mgC l^–1 d^–1; the ratio of those to total respiration of phytoplankton was 6%, 17% and 77%, respectively. The production of size-fractionated phytoplankton corresponding to <200 m, <10 m and <3 m in enclosures was 2.19 ± 1.63, 2.08 ± 1.75 and 0.22 ± 0.08 mgC l^–1 d^-1, respectively. Mean community respiration rates were 1.25 ± 1.55, 1.17 ± 1.42 and 0.47 ± 0.32 mgC l^–1 d^–1, respectively. The average production of phytoplankton corresponding to micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton was 0.11, 1.86 and 0.22 mgC l^–1 d^–1, respectively. The ratio of those to the total production of phytoplankton was 5%, 85% and 10%, respectively. The mean respiration rate of different size groups were 0.08, 0.72 and 0.46 mgC l^–1 d^–1, the ratio of those to total respiration of phytoplankton was 6%, 57% and 37%, respectively. The concentrations of chlorophyll-a of the phytoplankton in the corresponding size of micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) plankton in the experimental ponds were 19.3, 98.2 and 11. 9 g l^–1, respectively. The ratio of those to the total chlorophyll-a was 15%, 76% and 9%, respectively. The concentrations of chlorophyll-a of phytoplankton micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton in enclosures were 1.7, 34.3 and 3.0 g l^–1, respectively. The ratio of those to the total chlorophyll-a was 4%, 88% and 8%, respectively.     

Mercury budget of an upland-peatland watershed

Inputs, outputs, and pool sizes oftotal mercury (Hg) were measured in a forested 10 hawatershed consisting of a 7 ha hardwood-dominatedupland surrounding a 3 ha conifer-dominatedpeatland. Hydrologic inputs via throughfall andstemflow, 13±0.4 g m^–2 yr^–1over the entire watershed, were about doubleprecipitation inputs in the open and weresignificantly higher in the peatland than in theupland (19.6 vs. 9.8 g m^–2 yr^–1). Inputs of Hg via litterfall were 12.3±0.7g m^–2 yr^–1, not different in thepeatland and upland (11.7 vs. 12.5 g m^–2yr^–1). Hydrologic outputs via streamflow were2.8±0.3 g m^–2 yr^–1 and thecontribution from the peatland was higher despiteits smaller area. The sum of Hg inputs were lessthan that in the overstory trees, 33±3 gm^–2 above-ground, and much less than eitherthat in the upland soil, 5250±520 gm^–2, or in the peat, 3900±100 gm^–2 in the upper 50 cm. The annual flux of Hgmeasured in streamflow and the calculated annualaccumulation in the peatland are consistent withvalues reported by others. A sink for Hg of about20 g m^–2 yr^–1 apparently exists inthe upland, and could be due to either or bothstorage in the soil or volatilization.     

Clozapine and Several Other Antipsychotic/Antidepressant Drugs Preferentially Block the Same ‘Core’ Fraction of GABAA Receptors

Clozapine and several other antipsychotic/antidepressant drugs that fully or partially block GABA_A receptors were tested at concentrations that reversed the inhibitory effect of 1 M GABA on ³⁵S-t-butylbicyclophosphorothionate ([³⁵S]TBPS) binding to rat forebrain membranes only about 20–30%, here designated core fractions. Clozapine at 10 M reverses 1 M GABA 25 ± 4.0% (n = 23) (its core fraction). Fourty three compounds were tested alone, and pairwise together with 10 M Clozapine. The core fractions of some of the compounds yielded significant additive reversals together with 10 M Clozapine, while others did not. A group of 14 compounds of which 7 are clinically effective antipsychotic drugs, including Chlorprothixene, Clomacran, Clopipazan, Fluotracen, Sulforidazine, Thioproperazine, and cis-Thiothixene, were statistically non-additive with 10 M Clozapine, suggesting that all of these drugs selectively block the same core population of GABA_A receptors as Clozapine. These non-additivities also suggest that Clozapine at 10 M fully saturates a subset of GABA_A receptors blocked by 1 M GABA. Therefore, Clozapine probably blocks 2 or more types of GABA_A receptors, but only half of the receptors that are sensitive to 1 M GABA. A second group of 12 compounds of which 6 are clinically active antidepressant/antipsychotic drugs including Amoxapine, Clothiapine, Dibenzepine, Inkasan (Metralindole), Metiapine and Zimelidine were slightly, but significantly, additive with Clozapine suggesting that these compounds block most of Clozapine's core fraction, plus a small additional fraction. A third group consisted of ten compounds that yielded larger (R > 80) and statistically highly significant additivities with Clozapine. Complete additivity was obtained with Bathophenanthroline disulfonate, and Isocarboxazid, suggesting that they block GABA_A receptors other than those blocked by 10 M Clozapine. Seven classical GABA_A receptor blockers, also tested at concentrations yielding 21 to 33% reversal alone, were all significantly additive with 10 M Clozapine, but in no case was the additivity complete. The largest additivity was obtained with Pitrazepine (21%) and the smallest with Tubocurarine (9%). These results provide further support for the notion that selective blockade of the same subset of GABA_A receptors may contribute to the clinical antipsychotic/antidepressant effects of Clozapine. The B_opt values for Clozapine are 50 ± 1.7% and 26 ± 2.6% ( n = 3) in whole rat forebrain and cerebellum, respectively, confirming that clozapine-sensitive GABA_A receptors are unevenly distributed in the brain. The sedative and anxiolytic properties of Clozapine and other antipsychotic drugs may be due to selective blockade of GABergic disinhibition at certain interneurons.     

Pre-epithelial mucus layer in the colon of conventional and germ-free rats

Summary The pre-epithelial mucus layer (PML) and epithelial mucins were studied by mucin histochemistry in 10m-thick celloidinstabilized cryostat sections in the proximal and distal colon of conventional and germ-free rats aged 120 and 350 days. No continuous PML was found in the proximal colon. A continuous mucus blanket, of fairly homogenous thickness, was observed in the distal colon, where the PML-thickness was 40±24 m at 120 days of age and 44±22 at 350 days of age in conventional rats, and 25±17m (120 days) and 22±10 (350 days) in germ-free rats. The stainability of the PML by periodic acid-Schiff and Alcian Blue at pH 2.5 and 1.0 was stronger in conventional rats than in germ-free rats, indicating higher concentrations of mucosubstances and of acid and sulphated mucins, respectively. The PML of the conventional rat distal colon showed a stratified structure of up to eight sublayers. In the distal colon of germ-free rats, the whole gut wall thickness was reduced 47% compared to the conventional rat (germ-free: 185±73m, conventional: 350±115m). No stratification of the PML was observed. The presence of intestinal microflora obviously had a strong influence on the thickness, compactness, mucin content, mucin composition and structure of the pre-epithelial mucus layer.     

Cryphodera kalesari,a new heteroderid nematode species from Haryana,India

Cryphodera kalesari n. sp., recorded on Colebrookea oppositifolia Sm. from the Kalesar forests (Haryana), India, is described. Females: swollen, saccate, with two to three lip annules, with vulval lips protruding. Second stage juveniles: length 384±19 m, spear=26.5±1 m, tail 46.5±6 m, hyaline portion 21.5±2.5 m, en face dorsal and ventral arcs of head skeleton bifurcate. Males: not found.     

Warm blood cardioplegia reduces the fall in the intracellular concentration of taurine in the ischaemic/reperfused heart of patients undergoing aortic valve surgery

Summary The effect of cold and warm intermittent antegrade blood cardioplegia, on the intracellular concentration of taurine in the ischaemic/ reperfused heart of patients undergoing aortic valve surgery, was investigated. Intracellular taurine was measured in ventricular biopsies taken before institution of cardiopulmonary bypass, at the end of 30 min of ischaemic arrest and 20 min after reperfusion. There was no significant change in the intracellular concentration of taurine in ventricular biopsies taken after the period of myocardial ischaemia in the two groups of patients (from 10.1 ± 1.0 to 9.6 ±0.9mol/g wet weight for cold and from 9.3 ± 1.3 to 10.0 ± 1.3mol/g wet weight for warm cardioplegia, respectively). Upon reperfusion however, there was a fall in taurine in both groups but was only significant (P 0.05) in the group receiving cold blood cardioplegia (6.9 ± 0.8mol/g wet weight after cold blood cardioplegia versus 8.0± 0.8mol/g wet weight following warm blood cardioplegia). Like taurine, there were no significant changes in the intracellular concentration of ATP after ischaemia in the two groups of patients (from 3.2 ± 0.32 to 2.95 ± 0.43mol/g wet weight for cold and from 2.75 ± 0.17 to 2.62 ± 0.21mol/g wet weight for warm cardioplegia, respectively). However upon reperfusion there was a significant fall in ATP in both groups with the extent of the fall being less in the group receiving warm cardioplegia (1.79 ± 0.19mol/g wet weight for cold and 1.98 ± 0.27mol/g wet weight for warm cardioplegia, respectively). This work shows that reperfusion following ischaemic arrest with warm cardioplegia reduces the fall in tissue taurine seen after arrest with cold cardioplegia. Accumulation of intracellular sodium provoked by hypothermia and a fall in ATP, may be responsible for the fall in taurine by way of activating the sodium/taurine symport to efflux taurine.     

Storage,mobilization and interrelations of starch,sugars, protein and fat in the ray storage tissue of poplar trees

The seasonal pattern in starch, various sugars, protein, and fat, and their interrelationship, has been followed in 3-year-old branch wood of poplar trees (Populus x canadensis Moench robusta) under natural site conditions. The deposition of starch, protein and fat proceeds at different times. Starch accumulates from May until October, fat mainly during the summer months, and protein when the leaves are yellowing in September and October. The maximum concentrations in the branch wood were 15–18 g starch, 6–9 g protein, 4–8 g fat, 10–15 g sucrose, and up to 30 g total sugars per milligram dry weight (DW). During starch deposition periods no increased sucrose level is found in the tissue. The maximum daily starch deposition rate was 0.2–0.4 g starch/day/mg DW of wood. During starch hydrolysis in late autumn and winter, a dramatic increase in sucrose and its galactosides is measured (up to 15–27 g/mg DW in total). In early spring, before budbreak, the concentrations of these sugars diminishes sharply. In contrast to this clear-cut starch-to-sugar conversion in autumn no significant starch-to-fat conversion is detected. An elevated content of free glycerol, however, is found in winter. In spring, starch and storage protein are mobilized completely, or almost completely, in poplar twig wood. A noteworthy pool of maltose is found transiently during autumn (up to 8 g/mg DW) and again in spring. The results demonstrate that the individual storage materials, e.g. starch, protein, and fat, are accumulated fairly independently in the wood storage parenchyma. Tissue sugar levels, in contrast, appear to be closely related to the seasonal variations in starch content, on the one hand, and to the acclimation and deacclimation of the cells, on the other. The interrelations of the storage materials and sugars are discussed.     

Development of an L6 myoblast in vitro model of moniliformin toxicosis

L6 myoblasts were used as an in vitro model to investigate the role of moniliformin and its interaction with monensin in turkey knockdown syndrome and sudden death syndromes in poultry. Cell viability and microscopic and ultrastructural alterations noted in L6 myoblasts cultured in the presence of moniliformin (0.0–0.3 g/l) were compared to those observed in parallel cultures also containing one of the following compounds: selenium (0–0.004 ng/l), thiamine (0–0.3 g/l), or pyruvate (0–0.46 g/l). Marked dilation of the RER, membranous whorls, glycogen deposition, membrane-bound cytoplasmic inclusions and necrosis were observed in myoblasts exposed to 0.03/2-0.30 g moniliformin/l medium. Supplementation of medium with thiamine and pyruvate, or selenium, provided significant protection to cells exposed to 0.0–0.3 g/l or 0.0–0.15 g moniliformin/l, respectively. Dose-dependent differences in protein and ATP production were not detected. Myoblasts grown in medium containing 0–0.15 g moniliformin/l and 7.5–50.0 M A23187, beauvericin or monensin had degrees of cytotoxicity similar to parallel cultures receiving only an ionophore. L6 myoblasts were a useful model of moniliformin toxicosis. The findings of this study suggest cytotoxicity due to moniliformin in L6 myoblasts may be due in part to oxidative damage and altered pyruvate metabolism, and that moniliformin does not predispose myoblasts to ionophore toxicosis. This study supports the results of in vivo investigations in poultry that moniliformin and monensin do not act synergistically to induce knockdown or monensin toxicosis.     

Effect of Midthoracic Spinal Cord Constriction on Catalytic Nitric Oxide Synthase Activity in the White Matter Columns of Rabbit

The distribution and changes of catalytic nitric oxid synthase (cNOS) activity in the dorsal, lateral and ventral white matter columns at midthoracic level of the rabbit's spinal cord were studied in a model of surgically-induced spinal cord constriction performed at Th7 segment level and compared with the occurrence of nicotinamide adenine dinucleotide phosphate diaphorase expressing and neuronal nitric oxide synthase immunoreactive axons in the white matter of the control thoracic segments. Segmental and white-column dependent differences of cNOS activity were found in the dorsal (141.5 ± 4.2 dpm/m protein), lateral (87.3 ± 11.5 dpm/m protein) and ventral (117.1 ± 7.6 dpm/m protein) white matter columns in the Th5-Th6 segments and in the dorsal (103.3 ± 15.5 dpm/m protein), lateral (54.9 ± 4.9 dpm/m protein), and ventral (86.1 ± 6.8 dpm/m protein) white matter columns in the Th8-Th9 segments. A surgically-induced constriction of Th7 segment caused a disproportionate response of cNOS activity in the rostrally (Th5-Th6) and caudally (Th8-Th9) located segments in both lateral and ventral white matter columns. While a statistically significant decrease of cNOS activity was detected above the constriction site in the ventral columns, a considerable, statistically significant increase of cNOS activity was noted in the white lateral columns below the site of constriction. It is reasoned that the changes of cNOS activity may have adverse effects on nitric oxide (NO) production in the white matter close to the site of constriction injury, thus broadening the scope of the secondary mechanisms that play a role in neuronal trauma.