Effect of alpha-MSH on the corticosteroid production of isolated zona glomerulosa and zona fasciculata cells

α-MSH (10^?9 ? 6×10^?7M) potentiates the effect of ACTH (10^?11 ? 5×10^?9M) on adrenocortical steroidogenesis decreassng ED₅₀ of ACTH from 220 to 183 pg/ml on zona fasciculata corticosterone-, and from 739 to 437 pg/ml on zona glomerulosa aldosterone production. α-MSH alone increases aldosterone production of zona glomerulosa cells in doses (10^?9 ? 6×10^?7M) that do not stimulate zona fasciculata corticosterone production. The response of zona glomerulosa aldosterone production to α-MSH can be characterized by a bi-phase dose-response curve.     

Effect of prostacyclin on perfusion pressure, electrical activity, rate and force of contraction in isolated rat and rabbit hearts.

Prostacyclin when added to medium perfusing rat and rabbit hearts caused an increase in perfusion pressure at concentrations from 1 pg/ml ? 1 ng/ml (2.8 × 10^?12 ? 2.8 × 10^?9M) and a decrease at higher concentrations. Rhythm disturbances were observed with low prostacyclin concentrations in 6 of 10 rat hearts and 2 of 5 rabbit hearts studied. Increased heart rates were seen in the isolated rat hearts but not in the rabbit hearts. Force of contraction of isolated rat hearts was increased with increasing prostacyclin concentrations up to 100 pg/ml. Higher concentrations decreased contractile force. No inotropic effects were seen with rabbit hearts.     

Blood platelets of the cheetah (Acinonyx jubatus)

The blood platelet count and platelet morphology of 22 adult cheetahs was investigated. The platelet counts of the animals displayed a normal distribution, with a mean count of 344×10⁹/l and a mean platelet volume of 11 fl. Morphological and ultrastructural features of the cheetah platelets revealed the typical platelet morphology of anuclear cells, with granules scattered throughout the cytoplasm. The characteristic surface canalicular system and microtubules were present. True cross‐sections of the platelets had a mean area of 2.146 µm², circumference of 6.805 µm, and mean minimum and maximum projections of 1.000 µm and 2.933 µm, respectively. Zoo Biol 23:263–271, 2004. © 2004 Wiley‐Liss, Inc.     

Interim analysis of safety and efficacy of ruxolitinib in patients with myelofibrosis and low platelet counts

Background

Ruxolitinib, a Janus kinase 1 and 2 inhibitor, demonstrated improvements in spleen volume, symptoms, and survival over placebo and best available therapy in intermediate-2 or high-risk myelofibrosis patients with baseline platelet counts ≥100?×?10⁹/L in phase III studies. The most common adverse events were dose-dependent anemia and thrombocytopenia, which were anticipated because thrombopoietin and erythropoietin signal through JAK2. These events were manageable, rarely leading to treatment discontinuation. Because approximately one-quarter of MF patients have platelet counts <100?×?10⁹/L consequent to their disease, ruxolitinib was evaluated in this subset of patients using lower initial doses. Interim results of a phase II study of ruxolitinib in myelofibrosis patients with baseline platelet counts of 50-100?×?10⁹/L are reported.

Methods

Ruxolitinib was initiated at a dose of 5 mg twice daily (BID), and doses could be increased by 5 mg once daily every 4 weeks to 10 mg BID if platelet counts remained adequate. Additional dosage increases required evidence of suboptimal efficacy. Assessments included measurement of spleen volume by MRI, MF symptoms by MF Symptom Assessment Form v2.0 Total Symptom Score [TSS]), Patient Global Impression of Change (PGIC); EORTC QLQ-C30, and safety/tolerability.

Results

By week 24, 62% of patients achieved stable doses ≥10 mg BID. Median reductions in spleen volume and TSS were 24.2% and 43.8%, respectively. Thrombocytopenia necessitating dose reductions and dose interruptions occurred in 12 and 8 patients, respectively, and occurred mainly in patients with baseline platelet counts ≤75?×?10⁹/L. Seven patients experienced platelet count increases ≥15?×?10⁹/L. Mean hemoglobin levels remained stable over the treatment period. Two patients discontinued for adverse events: 1 for grade 4 retroperitoneal hemorrhage secondary to multiple and suspected pre-existing renal artery aneurysms and 1 for grade 4 thrombocytopenia.

Conclusions

Results suggest that a low starting dose of ruxolitinib with escalation to 10 mg BID may be appropriate in myelofibrosis patients with low platelet counts.

Trial registration

ClinicalTrials.gov:NCT01348490.

     

Comparison of bacteria from deep subsurface sediment and adjacent groundwater

Samples of groundwater and the enclosing sediments were compared for densities of bacteria using direct (acridine orange direct staining) and viable (growth on 1% PTYG medium) count methodology. Sediments to a depth of 550 m were collected from boreholes at three sites on the Savannah River Site near Aiken, South Carolina, using techniques to insure a minimum of surface contamination. Clusters of wells screened at discreet intervals were established at each site. Bacterial densities in sediment were higher, by both direct and viable count, than in groundwater samples. Differences between direct and viable counts were much greater for groundwater samples than for sediment samples. Densities of bacteria in sediment ranged from less than 1.00×10⁶ bacteria/g dry weight (gdw) up to 5.01 ×10⁸ bacteria/gdw for direct counts, while viable counts were less than 1.00×10³ CFU/gdw to 4.07×10⁷ CFU/gdw. Bacteria densities in groundwater were 1.00×10³–6.31×10⁴ bacteria/ml and 5.75–4.57×10² CFU/ml for direct and viable counts, respectively. Isolates from sediment were also found to assimilate a wider variety of carbon compounds than groundwater bacteria. The data suggest that oligotrophic aquifer sediments have unique and dense bacterial communities that are attached and not reflected in groundwater found in the strata. Effective in situ bioremediation of contaimination in these aquifers may require sampling and characterization of sediment communities.     

Experimental acute Babesia caballi infections: II. Response of platelets and fibrinogen

Ponies were acutely infected with Babesia caballi by inoculation with infected red blood cells (RBCs) containing 1 × 10⁸ and 1 × 10⁹ piroplasms. A series of blood samples taken before and after inoculation were analyzed for platelets and fibrinogen, and the results compared with similar analyses made on challenged, premunized ponies and on equids inoculated with uninfected RBCs. In acutely infected animals there were immediate decreases in platelet counts that persisted at least through Day 18 after inoculation (AI). Concomitantly, plasma fibrinogen levels rose, reaching peak values between Days 6–17. Clot retractions in vitro were impaired in these ponies during Days 9–16. No large diminutions in platelet counts or elevations of fibrinogen levels were observed in the challenged, premunized ponies or the group transfused with uninfected RBCs. In fact, the effect of challenge was to maintain or increase platelet counts. Our results plainly indicate that B. caballi can elicit alterations in clotting factor levels in its hosts during acute infections.     

The relationship between sperm concentration and fertilization in vitro of rabbit ova

Different concentrations of in utero incubated rabbit sperm (1.5 × 10⁴-120 × 10⁴ /ml) were tested to determine whether there is a relationship between sperm concentration and level of fertilization achieved “in vitro” of rabbit ova. While low concentrations (1.5 × 10⁴-4.5 × 10⁴ /ml) resulted in relatively low fertilization (23–36%), those in the range of 13 × 10⁴?120 × 10⁴ /ml gave fertilization rates of 65–83%. Consistently high results were obtained with sperm counts above 40 × 10⁴ /ml. This is in agreement with the concentration of spermatozoa found in vivo in the Fallopian tubes around the time of fertilization (50 × 10⁴ /ml).     

Expression ofβ-galactosidase and luciferase in insect cell lines infected with a recombinant AcMNPV

Summary An AcMNPV recombinant (Ac-gal-luc) carrying theβ-galactosidase and luciferase genes under the control of the p10 and polyhedrin promoters, respectively, was used to study expression in nine insect cell lines. All AcMNPV-permissive cell lines expressed both reporter genes with the coleopteran cell line,Anthonomus grandis (AGE), producing the highest concentrations ofβ-galactosidase (5.0×10⁶ pg/ml) and luciferase (2.67×10³ pg/ml). Both enzymes were detected as early as 12 h postinoculation in lysate samples of the AGE cell line.Helicoverpa armigera (HA), a nonpermissive cell line, expressedβ-galactosidase at 72 h postinoculation at a concentration of 3.5×10³ pg/ml. However, expression of luciferase was not detected. Expression of luciferase andβ-galactosidase was also not detected in the nonpermissiveHelicoverpa zea (HZ) cell line.     

Obesity, white blood cell counts, and platelet counts among police officers

Objective: To determine the association between several obesity indices (BMI, waist circumference, waist‐to‐hip and waist‐to‐height ratios, and abdominal height) and hematologic parameters [white blood cell (WBC) and platelet counts] among police officers. Research Methods and Procedures: The authors conducted this cross‐sectional study among 104 randomly selected officers (41 women and 63 men) from the Buffalo, NY, Police Department. Anthropometric measures were performed by clinic staff, and fasting blood samples were drawn for complete blood counts. Pearson's correlation, Student's t tests, ANOVA, analysis of covariance, and linear regression were used to assess the associations. Results: Officers ranged in age from 26 to 61 years old and were predominantly white. Among women, current smokers had significantly higher WBC counts (7.4 × 10³ cells/µL ± 1.4) than former (5.2 × 10³ cells/µL ± 1.4) or never smokers (5.6 × 10³ cells/µL ± 1.5) (p = 0.002). Women had similar WBC counts but higher mean platelet counts than men (p = 0.005). Among women, abdominal height was positively associated with platelet count after adjustment for depression (p for trend = 0.039). Among women and men, a non‐significant step‐wise trend was observed between abdominal height and mean WBC counts before and after adjustment for smoking, race, and physical activity. No association was observed between obesity and platelet count among men. Discussion: Abdominal height was significantly associated with increased platelet counts among female officers. No significant associations were observed between obesity and WBC or platelet counts among male officers.     

Effects of temperature on photosynthesis of two morphologically contrasting plant species along an altitudinal gradient in the tropical high Andes

The effects of temperature on photosynthesis of a rosette plant growing at ground level, Acaena cylindrostachya R. et P., and an herb that grows 20–50 cm above ground level, Senecio formosus H.B.K., were studied along an altitudinal gradient in the Venezuelan Andes. These species were chosen in order to determine – in the field and in the laboratory – how differences in leaf temperature, determined by plant form and microenvironmental conditions, affect their photosynthetic capacity. CO₂ assimilation rates (A) for both species decreased with increasing altitude. For Acaena leaves at 2900 m, A reached maximum values above 9 μmol m⁻² s⁻¹, nearly twice as high as maximum A found at 3550 m (5.2) or at 4200 m (3.9). For Senecio leaves, maximum rates of CO₂ uptake were 7.5, 5.8 and 3.6 μmol m⁻² s⁻¹ for plants at 2900, 3550 and 4200 m, respectively. Net photosynthesis-leaf temperature relations showed differences in optimum temperature for photosynthesis (A _o.t.) for both species along the altitudinal gradient. Acaena showed similar A _o.t. for the two lower altitudes, with 19.1°C at 2900 m and 19.6°C at 3550 m, while it increased to 21.7°C at 4200 m. Maximum A for this species at each altitude was similar, between 5.5 and 6.0 μmol m⁻² s⁻¹. For the taller Senecio, A _o.t. was more closely related to air temperatures and decreased from 21.7°C at 2900 m, to 19.7°C at 3550 m and 15.5°C at 4200 m. In this species, maximum A was lower with increasing altitude (from 6.0 at 2900 m to 3.5 μmol m⁻² s⁻¹ at 4200 m). High temperature compensation points for Acaena were similar at the three altitudes, c. 35°C, but varied in Senecio from 37°C at 2900 m, to 39°C at 3550 m and 28°C at 4200 m. Our results show how photosynthetic characteristics change along the altitudinal gradient for two morphologically contrasting species influenced by soil or air temperatures. Received: 5 July 1997 / Accepted: 25 October 1997     

Cell density dependent response of E. Coli cells to weak ELF magnetic fields

The effects of weak magnetic fields of extremely low frequency (ELF) on E. coli K12 AB1157 cells were studied by the method of anomalous viscosity time dependencies (AVTD). E. coli cells at different densities within a range of 5 × 10⁵–10⁹ cell/ml were exposed to ELF (sinusoidal, 30 μT peak, 15 min) at a frequency of 9 Hz. A transient effect with maximum 40–120 min after exposure was observed. Kinetics of the per-cell-normalised ELF effects fitted well to a Gaussian distribution for all densities during exposure. A maximum value of these kinetics and a time for this maximum were strongly dependent on the cell density during exposure. These data suggest a cell-to-cell interaction during response to ELF. Both dependencies had three regions close to a plateau within the ranges of 3 × 10⁵ − 2 × 10⁷ cell/ml, 4 × 10⁷ − 2 × 10⁸ cell/ml and 4 × 10⁸–10⁹ cell/ml and two rather sharp transitions between these plateaus. The effect reached a maximum value at a density of 4 × 10⁸ cell/ml. Practically no effect was observed at the lowest density of 3 × 10⁵ cell/ml. The data suggested that the ELF effect was mainly caused by a secondary rather than a primary reaction. The filtrates from exposed cells neither induced significant AVTD changes in unexposed cells nor increased the ELF effect when were added to cells before exposure. The data did not provide evidence for significant contribution of stable chemical messengers, but some unstable compounds such as radicals could be involved in the mechanism of cell-to-cell interaction during response to ELF. The results obtained were also in accordance with a model based on an re-emission of secondary photons during resonance fluorescence. Bioelectromagnetics 19:300–309, 1998. © 1998 Wiley-Liss, Inc.     

Factors influencing biocontrol of jimsonweed (Datura stramonium L.) with the leaf-spotting fungus Alternaria crassa

In greenhouse tests, Alternaria crassa (Sacc.) Rands killed > 80% of inoculated jimsonweed (Datura stramonium L.) seedlings within 14 days following a 9-h dew period at 25°C with 1 × 10⁵ spores/ml, and after 8 h of dew at 1 × 10⁶ spores/ml. At least 10 h of dew with 1 × 10⁵ spores/ml and 9 h of dew with 1 × 10⁶ spores/ml were required to obtain 100% mortality of fungus-inoculated plants. Growth stage and inoculum concentration studies revealed that higher concentrations of inoculum were required to obtain 100% mortality of larger plants. Weed control was significantly reduced by day/night air temperatures of 35°C and 24°C, respectively, at all inoculum concentrations as compared to the controls at lower air and dew temperature regimes. The results of these studies indicate that A. crassa has potential as a biological herbicide for the control of jimsonweed.     

Platelet gel supernatant as a potential tool to repopulate acellular heart valves

Objective

The aim of this study was to repopulate decellularized heart valve matrices with ovine mesenchymal stem cells (oMSCs) by the use of platelet gel (PG) supernatant, a storage vehicle for growth factors.

Methods

oMSCs were exposed to different concentrations of PG‐released supernatant and cell proliferation was evaluated using the MTS assay. oMSC motility and invasiveness were assayed using a Boyden chamber. A quantitative sandwich enzyme immunoassay was used to examine amounts of bFGF and TGF‐β1 in the PG supernatant. Repopulation of acellular heart valve matrices was stimulated by seeding matrices with oMSCs supplemented with the PG supernatant.

Results

The most significant increase in proliferation induced by PG supernatant appeared at 1 × 10⁵ plts/ml concentration. Higher concentrations evoked reduction of the stimulatory process. oMSC motility was most significantly stimulated at 1 × 10⁶ plts/ml. Stimulating invasiveness of oMSCs needed the much higher concentration of 2 × 10⁶ plts/ml. Immunoassays revealed that sheep PG supernatant contains 184.8 pg/ml bFGF and 60.5 ng/ml TGF‐β1. Moreover, repopulation of acellular heart valve matrices was significantly enhanced by PG supernatant addition and resulted in upregulation of the myofibroblast marker alpha‐smooth muscle actin.

Conclusions

Growth factors released from platelets had the potential to induce cell repopulation in a heart valve tissue engineering procedure, through stimulation of mesenchymal stem‐cell migration and invasion.     

Metabolic behavior of acetyl glyceryl ether phosphorylcholine on interaction with rabbit platelets

The metabolic fate of 1-O-[³H]alkyl-2-acetyl-sn-glycero-3-phosphorylcholine ([³H]-AGEPC) upon interaction with rabbit platelets was investigated. [³H]AGEPC was converted to a product identified as the long-chain fatty acyl analog. The reaction was unaffected by extracellular calcium. After a lag time of 30 to 60 s the kinetics of the conversion was linear. The rate of the reaction was found to be a function of platelet and AGEPC concentrations. Of the [³H]AGEPC (10^?9m) 85 ± 5% was processed into the-long chain fatty acyl analog within 1 h when incubated at 37 2C with a 1.25 × 10⁹ platelets per milliliter suspension. A maximal number of 1200 to 3600 [³H]AGEPC molecules were converted to the long-chain fatty acyl derivative per minute per platelet in the presence of 2 mm EDTA. Under similar conditions the 1-O-[³H]alkyl-2-(lyso)-sn-glycero-3-phosphorylcholine ([³H]lysoGEPC) also was transformed to a comparable long-chain fatty acyl derivative at a much slower rate and to a lower extent. No significant increase in lysoGEPC was noted in incubation mixtures containing [³H]AGEPC. The possible direct transacylation of AGEPC upon interaction with platelets is discussed as well as the possible involvement of this reaction in directly triggering the platelet response to AGEPC stimuli.     

Interaction of HaNPVs with two novel insecticides against Helicoverpa armigera Hubner (Noctuidae: Lepidoptera)

Nucleopolyhedrosis viruses can be utilized for effective management of agriculture pests. Their efficacy can be increased if they are mixed with certain insecticides. In the current study, HaNPV was mixed with two insecticides: spinetoram and emamectin benzoate in various combinations and applied to larvae of H. armigera in laboratory conditions. There were a total of 15 combinations of HaNPV with each of the two insecticides in addition to five doses of HaNPV and three doses of insecticides alone. The synergistic and antagonistic effects of combinations were explored. The results revealed that there was synergistic effect of HaNPV @ 0.5 × 10⁹ PIB/ml × Spinetoram @ 40, 20, 10 ml/100 L of water. In case of emamectin benzoate, synergistic effects were recorded at 1 × 10⁹ PIB/ml HaNPV × emamectin benzoate @ 100 ml/100 L of water. However, 0.5 × 10⁹ PIB/ml HaNPV has synergistic effects with all three doses of emamectin benzoate. The results suggested that HaNPV can be used in combination with spinetoram and emamectin benzoate for the management of resistant population of H. armigera.     

Laboratory studies on the fungus Verticillium lecanii, a larval pathogen of the large elm bark beetle (Scolytus scolytus)

From 1972 to 1974, estimates of the natural larval mortality (> second instar) of elm bark beetles caused by pathogenic organisms were always below 7'5 % of the beetle population. The pathogenic fungus Verticillium lecanii was frequently isolated from field-collected dead larvae, and in the laboratory all larvae were killed in 5 days when exposed to spore concentrations of 4·5 × 10⁶ spores/ml. V. lecanii begins to lose its pathogenicity after prolonged culture on artificial media. The time taken for V. lecanii to kill Scolytus scolytus larvae when exposed to a logarithmic series of spore dilutions from 9·1 × 10⁷/ml to 9·1 × 10³/ml increased with decreasing amounts of inoculum. Even at spore concentrations as low as 9·1 × 10³/ml the mortality of treated larvae was greater than that of untreated individuals. At 100% r.h. all treated larvae were killed over a temperature range of 5–30 °C; those maintained at 25 °C were killed most rapidly and those kept at 5 °C the slowest.     

Epidermal growth factor: Characteristics of specific binding in membranes from liver,placenta, and other target tissues

Epidermal growth factor, a 6,400-dalton polypeptide from the mouse submaxillary gland, binds specifically to cells and membranes derived from a variety of human, rat, mouse, and bovine tissues. Liver, placenta, skin, cornea, and cultured chondrocytes, Hela cells, and Chang liver cells bind large amounts of epidermal growth factor, whereas fat cells, resting and lectin-stimulated human peripheral lymphocytes, mouse thymocytes, cultured rat hepatoma cells, and mammary cells from virgin and pregnant mice bind little or no epidermal growth factor. The binding site for epidermal growth factor is distinct from receptors for other anabolic peptides such as insulin, nerve growth factor, and growth hormone. The binding of epidermal growth factor is rapid and reversible. The rate constant of association is approximately 10⁶ mole^?1 sec^?1, the rate constant of dissociation is about 6 × 10^?4 sec^?1, and the apparent equilibrium dissociation constant is about 10^?9m. Trypsin at low concentrations (50–200 μg/ml) destroys the receptor site for epidermal growth factor. The binding of epidermal growth factor by membranes is not accompanied by appreciable degradation of the peptide present in the medium or of that bound to the membranes. Use can be made of the high affinity and specificity of membranes for epidermal growth factor to measure by a competitive binding assay as little as 200 pg of EGF per ml (3 × 10^?11m).     

Cytometric determination of genome size in <Emphasis Type="Italic">Colchicum</Emphasis> species (Liliales,Colchicaceae) of the western Mediterranean area

Genome size has been studied for the first time in the Colchicum genus. Values obtained by flow cytometry were quite stable and specific to each taxon: C. autumnale L., 2C=5.89±0.22 pg, equivalent to 5.7×10 ⁹ bp (2 n=4 x=36); C. alpinum DC., 2C=8.06±0.24 pg, equivalent to 7.8×10 ⁹ bp (2 n=6 x=56); C. lusitanum Brot., 2C=10.7±0.67 pg, equivalent to 10.3×10 ⁹ bp (2 n= approx. 10 x=90–92 and 94–96); C. multiflorum Brot., 2C=16.5±0.69 pg, equivalent to 15.9×10 ⁹ bp, (2 n= approx. 16 x=140–148); C. corsicum Baker, 2C=21.3±0.99 pg, equivalent to 20.6×10 ⁹ bp (2 n=22 x= approx. 198±2). These values are well below those published for Liliaceae stricto sensu. In Colchicum species from the western Mediterranean area, genome size was highly correlated with ploidy level ( R ²=0.99, P<0.001). This relationship is consistent with most previous results, with our new chromosome number count for C. corsicum and with our correction of published erroneous counts for C. lusitanum (2 n=102–108). The Calabrian population appeared to be distinct from all of the other plants of the C. alpinum group. Reproducible and accurate, cytometry appears to be a particularly appropriate method for studying this polyploid genus in Western Europe, taking into account that chromosome numbers are difficult to enumerate. It can guide future taxonomic research because it reveals similarities or differences between taxa within this difficult complex.     

Progressive increase with time after sensitization in the functional affinity of T lymphocytes

The dose response relationship in peritoneal cell migration inhibition, elicited by various concentrations of ABA-Tyr, was studied in guinea pigs sensitized with a standard dose of ABA-Tyr. The reactivity to 2 × 10^?7 or 2 × 10^?8 mole/ml appeared at 2 wk, and remained at the maximum level from 4 wk to 8 mo after sensitization. The inhibition by 2 × 10^?9 mole/ml increased up to 4 mo and 2 × 10^?10 mole/ml was first inhibitory at $\text{6}\text{1}\text{2}$ mo. The change in the slope of the dose response curve was a property of the ABA-specific cells. As there is no B-cell response to ABA-Tyr, the finding shows that the functional affinity of specific T cells progressively increases with time after sensitization.     

Effect of different salinities of a dynamic water system on biofilm formation

AISI-1020 carbon steel coupons were fixed onto a water circulation loop in order to study the effect of varying NaCl concentrations on formation of biofilms by natural populations of microorganisms. Overall, we observed a reduction in the number of bacteria attached to the metal surfaces as NaCl levels increased. At 12.85 and 80 g/l NaCl, the respective bacterial counts were: 1.7×10⁹ CFU/cm² and 7.5×10² CFU/cm² for aerobic species; 1.3×10⁴ CFU/cm² and 2.1×10 CFU/cm² for anaerobic species; and 1.8×10³ CFU/cm² and 4.6×10 CFU/cm² for sulfate-reducing species. However, the opposite trend was observed for the numbers of iron-reducing bacteria: 4.1×10⁶ CFU/cm² at 12.85 g/l NaCl and 7.5 10⁸ CFU/cm² at 80 g/l NaCl, respectively. Fungal counts remained constant throughout the experimental period. The salt concentration at which the maximum corrosion rate was observed was 35 g/l. In view of the marked loss of metal mass recorded at this salinity, AISI-1020 carbon steel proved to belong to the group of alloys less resistant to corrosion. Journal of Industrial Microbiology & Biotechnology (2000) 25, 45–48. Received 07 December 1999/ Accepted in revised form 25 April 2000