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The prebreakdown and breakdown phases of a pseudospark discharge are investigated using the two-dimensional kinetic plasma simulation code OOPIC™ PRO. Trends in the peak electron current at the anode are presented as function of the hollow cathode dimensions and mean seed injection velocities at the cavity back wall. The plasma generation process by ionizing collisions is examined, showing the effect on supplying the electrons that determine the density of the beam. The mean seed velocities used here are varied between the velocity corresponding to the energy of peak ionization cross section, 15 times this value and no mean velocity (i.e., electrons injected with a temperature of 2.5 eV). The reliance of the discharge characteristics on the penetrating electric field is shown to decrease as the mean seed injection velocity increases because of its ability to generate a surplus plasma independent of the virtual anode. As a result, the peak current increases with the hollow cathode dimensions for the largest average injection velocity, while for the smallest value it increases with the area of penetration of the electric field in the hollow cathode interior. Additionally, for a given geometry an increase in the peak current with the surplus plasma generated is observed. For the largest seed injection velocity used a dependence of the magnitude of the peak current on the ratio of the hole thickness and hollow cathode depth to the hole height is demonstrated. This means similar trends of the peak current are generated when the geometry is resized. Although the present study uses argon only, the variation in the discharge dependencies with the seed injection energy relative to the ionization threshold is expected to apply independently of the gas type. Secondary electrons due to electron and ion impact are shown to be important only for the largest impact areas and discharge development times of the study. [ABSTRACT FROM AUTHOR]

Thermopsis turcica Kit Tan, Vural & Küçüködük is an herbaceous perennial, endemic and listed as endangered species by IUCN in Turkey. This plant is noted for its unusual floral structure characterized by a 2-4 carpellary ovary. In this study, a DPD ( NADP+)-like gene was partially sequenced for the first time in T. turcica. Since there is no previous molecular genetic information available for T. turcica, RT-PCR was performed using degenerate primers targeted to conserved sequences of WUS protein homologues from related legume species. Amplified cDNAs of the expected size were sequenced and analyzed using bioinformatics tools. The analysis strongly suggested that a 283 bp PCR product was part of a dihydropyrimidine dehydrogenase (NADP+)-like coding sequence with a Flavin mononucleotide binding domain. The putative gene was named Tt- DPD and the partial CDS submitted to the NCBI database (accession number KT182937). This gene has not been identified previously in T. turcica. The DPD (NADP+) enzyme is the rate-limiting step in pyrimidine degradation, which is essential for the biosynthesis of beta-alanine and pantothenates in plants; it has also been shown to be required for normal seed development in Arabidopsis. Expression of Tt- DPD was monitored by both endpoint and real-time RT-PCR. High expression of the identified gene was observed in the mid-developmental stage of the pistil of T. turcica. The findings presented here provide a starting point for understanding the roles of this gene in pyrimidine catabolism in T. turcica. [ABSTRACT FROM AUTHOR]

The potential of algae-based fuel technologies for manufacturing renewable biofuels has been attracting interest from the scientific community. Biomass productivity and cellular lipid content are important parameters affecting the feasibility of using algae oil for biodiesel production. This study compares utilization of NaNO3, NH4Cl and urea as different nitrogen sources in terms of their effects on biomass productivity, fatty acid profile and accumulation in Scenedesmus obliquus. Cellular lipid accumulation was analyzed by gravimetric, fluorometric, and flow-cytometric methods, besides collecting spectrophotometric data for biomass productivity analysis. In addition, fatty acid profiles were compared by using gas chromatography-mass spectrometry. The alga can utilize all tested nitrogen sources successfully however growth rates demonstrate differences. Gravimetric lipid content analysis showed approximately a ≈1.5-fold increase in total lipid accumulation under NH4Cl regime when compared to that of NaNO3 and a ≈ 2-fold increase when compared to that of urea at the end of ten days cultivation course. Fatty acid profiles under different nitrogen regimes present variations especially under NH3Cl regime. Moreover, all lipid extracts mostly consist of saturated, straight- and branched-chain hydrocarbons of different chain lengths ranging from C16-C20 which grant a suitable profile for biodiesel production. Scenedesmus obliquus is a suitable species for biodiesel production. The results obtained from this study provide a better understanding of cultivation characteristics of this important species and support potential, future biodiesel production. [ABSTRACT FROM AUTHOR]

The possibility of micropropagation for the endangered Thermopsis turcica was investigated through an fruit ovule-embryo culture. This technique prevents embryo degradation at the early development stage, shortens breeding time, and enables efficient propagation of many plants from a single embryo, thus avoiding for breaking seed dormancy. Although a number of efficient propagation protocols of T. turcica has been reported for multiple shoot induction and plantlet regeneration from the seeds of T. turcica, to date no publication exists on any protocol on embryo culture of T. turcica. This paper reports on the optimisation of protocols for culturing of T. turcica fruit embryos. The protocol for embryo culture used in this research consisted of cracking the fruit, pitting it to remove the seed, excising the ovule-embryo from the seed, placing it on the medium modified from established Fabaceae embryo tissue culture media, extracting embryos from ovular integuments, and culturing. In the present study, extracted ovule-embryos were cultured on a Murashige and Skoog's medium supplemented with Zeatin (0.5 mg L-1), Giberellic acid (0.5 mg L-1), and Indole-3-acetic acid (0.2 mg L-1). Excised embryos from the ovular integuments were maintained on Giberellic acid-free MS medium. During culturing, cotyledons began to arise and grow plantlets. Regenerated plantles were rooted on a MS medium with Indole-3-butyric acid (2.0 mg L-1). These results show that embryo culture technique can be an alternative ex-situ conservation technique for in vitro propagation of the threatened rare plant species T. turcica. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the outcomes of moderate sedation with nitrous oxide/oxygen (N2O/O2) alone or combined with different dosages and administration routes of midazolam in uncooperative paediatric dental patients using the Bispectral Index System (BIS). Methods: This one-year clinical study examined first-visit moderate sedation performed in 240 healthy children aged 4-6 years. Subjects were randomly divided into four groups according to drug, route and dosage, as follows: Group 1 - 0.20 mg/kg midazolam (40 mg/ml) delivered intranasally; Group 2 - 0.75 mg/kg midazolam (15 mg/3 ml) delivered orally; Group 3 - 0.50 mg/kg midazolam (15 mg/3 ml) delivered orally. All children in these three groups also received inhalation sedation with 50%-50% N2O/O2, whereas children in Group 4 received inhalation sedation with 50%-50% N2O/O2 only. The outcome of sedation was evaluated as either 'successful', 'failed' or 'not accepted'. Results: The highest success rate was found in Group 1 (0.20 mg/kg intranasally, 87%), followed by Group 2 (0.75 mg/kg orally, 79%). The overall mean success rate for all groups was 73%. Conclusions: Moderate sedation can be successfully used in the clinical management of paediatric dental patients, with both intranasal and oral sedation using midazolam in conjunction with nitrous oxide found to be effective methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the relationship between humoral and cell-mediated immune response parameters and impairment of immune functions in children with Down syndrome (DS). The patient group was consisted of cytogenetically documented 32 children with DS. Lymphocyte subsets and natural killer cells were counted by flow-cytometry system. Levels of interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10 and tumour necrosis factor-alpha (TNF-α) were detected by enzyme-linked immunosorbent assay method. Serum IgG, IgM, IgA levels were measured by turbidimetric methods. The percentage of CD8+ lymphocytes and CD56+ cells of patients with DS were significantly higher, whereas CD20+ lymphocytes were lower than that of controls ( P < 0.05). The percentage of CD2 and CD4 levels and CD4/CD8 ratio of patients with DS and normal controls were similar ( P > 0.05). Levels of IL-4 and IL-10 were significantly increased, but IL-6 and TNF-α levels were decreased in children with DS ( P < 0.05). Levels of other studied cytokines between patients with DS and controls were not statistically different ( P > 0.05, for all). Serum IgG, IgM and IgA levels were found to be similar between the groups ( P > 0.05). It has been known that IL-4 and IL-10 are anti-inflammatory molecules which inhibit the synthesis of proinflammatory cytokines such as IL-6 and TNF-α. In this study, levels of IL-4 and IL-10 were significantly increased, but IL-6 and TNF-α levels were decreased in children with DS. These results may suggest that continuing anti-inflammatory state in DS and this process may explain the cause of recurrent infection of the disease. On the other hand, in contrast to the low percentage of CD20+ cells, high percentage of CD8+ and CD56+ cells were found. Our findings may demonstrate that the cell-mediated and humoral immune system parameters in children with DS were altered according to healthy children. [ABSTRACT FROM AUTHOR]

Tuzla geothermal basin is situated in north-western Turkey on the Biga Peninsula, which is located at the west end of the Northern Anatolian Fault system. Soil and water samples were collected between August 2003 and June 2004 to initiate development of a geochemical profile of surface and subsurface waters in the geothermal basin and radionuclide concentrations in soils. All water samples were found to fall within Turkish Water Quality Class 4, meaning they were remarkably contaminated for any water consumption sector (industrial, human use or agricultural) based on sodium and chloride ions. Such waters could be used only after appropriate water treatment. The water samples are of the chloride type in terms of geochemical evaluation. Preliminary geochemical evidence shows that the N–S flowing part of the Tuzla River acts as a natural barrier within the basin. Heavy metal concentrations in the soil samples show slight elevations, especially those obtained from the east part of the basin where thermal springs are dominant. Geochemical calculations were carried out with PHREEQC® software to determine equilibrium concentration of chemical species and saturation indices, by which it is suggested that chloride is the most important ligand to mobilize the heavy metals in the studied system. In addition, the activity concentration and gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides were determined in the soil using gamma-ray spectrometry. The soil activity ranged from 42.77 to 988.66 Bq kg−1 (averaging 138 Bq kg−1) for 238 U, 13.27 to 106.31 Bq kg−1 (averaging 32.42 Bq kg−1) for 232 Th, and 99.28 to 935.36 Bq kg−1 (averaging 515.44 Bq kg−1) for 40 K. The highest value of 238 U was found in the soil samples obtained from an area close to the hot spring. [ABSTRACT FROM AUTHOR]

Heated carbon dioxide (CO2) was used for pneumoperitoneum (Pp) to prevent hypothermia. This study aimed to investigate the relationship between the temperature of the insufflated CO2 and blood gases together with the core body temperature (CBT). A prospective controlled study was performed with 24 pigs weighing approximately 20 kg randomized into four groups of 6 pigs each. A pneumoperitoneum at 12 mmHg of pressure was applied for 60 min with the pig under general anesthesia. The CO2 temperature was 22°C in group 1, 37°C in group 2, and 7°C in group 3. In the “sham” group, pneumoperitoneum was not applied. Arterial blood pH and partial pressure of CO2 (PaCO2) were analyzed before insufflation, every 15 min during the pneumoperitoneum, and 15 min after the desufflation. The CBT was recorded before the insufflation, every 20 min during pneumoperitoneum, and 20 min after the desufflation. Blood gas analyses and CBT records for the “sham” group were performed at the same intervals. Arterial blood pH gradually decreased during pneumoperitoneum. At the 60th minute of pneumoperitoneum, a minimum decrease in arterial blood pH (0.04; p = 0.027) and a minimum increase in PaCO2 (3.67; p = 0.027) were recorded in group 3, whereas a maximum decrease in arterial blood pH (0.18; p = 0.027) and a maximum increase in PaCO2 (17.17; p = 0.027) were recorded in group 2. There was a significant negative correlation between PaCO2 and arterial blood pH in all the groups ( r = –0.993; p < 0.01). The mean values of CBT decreases were statistically significant in all the groups: group 1 ( p = 0.023), group 2 ( p = 0.026), group 3 ( p = 0.026), and “sham” group ( p = 0.024). The changes in PaCO2 were directly proportional and the changes in pH contrarily proportional to the temperature of the insufflated CO2. Significant differences in CBT decreases were found between the groups receiving heated gas and room temperature gas and the groups receiving heated gas and gas below room temperature. [ABSTRACT FROM AUTHOR]

Background Phenol injection, a less invasive method, has become more popular for the treatment of sinus pilonidalis. Recurrence rates after the use of phenol have been reported to be less than those after other surgical methods. Methods In this study, we applied 80% phenol to 143 patients with sinus pilonidalis. Patients were re- evaluated at 1, 3, 6, 12 and 24 months after the phenolization procedure to search for any recurrences. Age, sex, skin color, occupation, hair distribution, complaints, macroscopic characteristics of the lesion, pouch volume, microbiological yield, complications of phenol injection, healing time, and recurrences were determined. Results The mean follow-up period was 24 months and the recurrence rate was 8.3% (12 of 143 patients). Volume of the sinus tract and number of sinus orifices were determined to be the factors significantly affecting recurrences (p<.05). Conclusions Injection of 80% phenol is an ideal approach for the conservative treatment of sinus pilonidalis. This study confirms that this is an effective and costless method with low recurrence rates. [ABSTRACT FROM AUTHOR]

Hypocotyl explants of melon ( Cucumis melo L.) are capable of regenerating multiple shoots on Murashige and Skoog (1962) medium, augmented with 4.4 μ M benzylademne. Regeneration from the hypocotyl is much more rapid than the more commonly reported regeneration from cotyledonary explants, producing shoots within 2 wk compared to more than a month required for cotyledon explants. The rapid regeneration response depends on the presence of a fragment of the cotyledon remaining attached to the hypocotyl. Controls were performed to ensure that the regeneration was not due to the presence of the shoot apical bud of the melon seedling after explant production. Scanning electron microscopy revealed that microsurgery to remove the apical bud left no excess bud material. Regeneration from the proximal part of the hypocotyl was due to production of a new shoot apical meristem, observed by histology. The apical meristem can be produced before leaf primordia in regeneration from the hypocotyl, in contrast to the regeneration process from the melon cotyledon. [ABSTRACT FROM AUTHOR]

Vaginal metastasis from colonic cancer is an extreme case and often indicates a poor prognosis. More frequently tumor cells from the colonic lesions spread out to vagina by direct contiguous way. We present a case of rectal carcinoma with true metastasis to the vagina that was discovered after an interval of 15 mounts when vaginal bleeding and discharge became evident. To our knowledge, there are only a few other papers in the English language previously documenting this phenomenon. [ABSTRACT FROM AUTHOR]

Cardiovascular complications due to atherosclerosis (AS) are the major cause of mortality in hemodialysis (HD) patients. Inflammation may play an important role in the development of AS. Several studies have demonstrated the association of acute-phase proteins and cytokines with AS in the general population and in HD patients. Interleukin-10 (IL-10) is an anti-inflammatory cytokine. The aim of study was to compare serum levels inflammatory and anti-inflammatory indicators in HD patients according to the presence or absence of AS. Thirty-three HD patients were enrolled. AS was defined as the detection of plaques by Doppler ultrasonography. The patients were subgrouped according to the presence or absence of plaques. Serum levels of IL-1, IL-2, IL-6, IL-10, C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α) were measured. The factors for AS such as age, gender, hypertension, hyperlipidemia, and HD duration were also evaluated. We found that the patients with AS had significantly higher hs-CRP and lower IL-10. Blood pressure values were also increased in patients with AS. Additionally, there was an increased correlation between CRP and IL-10. AS(+) patients undergoing HD had low serum levels of anti-inflammatory cytokine IL-10 and high serum levels of hs-CRP. These results may suggest that the limitation of anti-inflammatory response in atherosclerotic uremic patients is a triggering or contributing factor for AS. [ABSTRACT FROM AUTHOR]

Arteriosclerosis is characterized by stiffening of arteries. The incremental elastic modulus (Einc) measurement is a good marker of arterial wall stiffness. Arteriosclerosis is characterized by stiffening of arteries. Metabolic, inflammatory, and hemodynamic alterations cause structural changes and vascular complications in end-stage renal disease. The aim of the present study was to evaluate the factors that may affect the development of arteriosclerosis by measurement of Einc in hemodialysis (HD) patients. Thirty-two patients (16 men and 16 women) on chronic HD with a mean age of 42.2 ± 19.3 (range, 15–80) were included in the study. The carotid Einc was measured to determine arteriosclerosis by high-resolution echo-tracking system. Einc measurement was calculated from transcutaneous measurements of carotid arterial internal diameter and wall thickness and carotid pulse pressure. Common carotid compliance (CCC) and distensibility (CCD) were determined from changes in carotid artery diameter during systole and simultaneously measured carotid pulse pressure. Serum levels of calcium (Ca), phosphorus (P), parathormone (PTH), ferritin, C-reactive protein (CRP), predialysis systolic blood pressure (SBP), predialysis diastolic blood pressure (DBP), pulse pressure (PP), age, HD duration, CCC, and CCD were correlated with Einc in all patients. A significant positive correlation was found between Einc and age (r = 0.40, p < 0.02), SBP (r = 0.39, p < 0.02), PP (r = 0.40, p < 0.02), Ca (r = 0.43, p < 0.01), CRP (r = 0.38, p < 0.02). As expected, Einc was correlated inversely with CCD (r = −0.77, p < 0.0001). The correlation between Einc and HD duration, DBP, ferritin, P, PTH, and CCC was not significant. In conclusion, the stiffening of carotid artery in HD patients is related not only to hemodynamic changes (increased SBP and PP) but also to metabolic (increased Ca) and inflammatory (increased CRP) responses. Carotid Einc is an accepted independent risk factor for cardiovascular mortality. Because of the positive correlation between Einc and serum Ca, vitamin D and Ca-containing P binder should be used carefully in HD patients. [ABSTRACT FROM AUTHOR]

Procalcitonin (PCT) has been described as a new marker of severe infection and sepsis. In this study, we investigated the serum levels of PCT during the hemodialysis (HD) in chronically hemodialyzed patients and whether the PCT levels were correlated with other cytokines. We measured pre- and post-HD PCT, interleukin (IL-1), IL-2, IL-6, IL-10, tumor necrosis factor-α (TNF-α) concentrations in 24 stable patients undergoing chronic HD [11 males and 13 females; age 41.2 ± 18.0 years, 12 h/week, with a Kt/V of 1.41 ± 0.35, polysynthane (PSN) membrane being used in all patients, without reuse]. Pre- and post-HD PCT concentrations were compared with cytokines such as IL-1, IL-2, IL-6, IL-10, TNF-α, and clinical parameters including age, blood pressure, leukocyte, hemoglobin levels, C-reactive protein (CRP), epoetin (EPO) doses, BUN, creatinine, parathormone (PTH), ferritin, and transferrin levels. Pre- and post-HD serum PCT levels were similar (0.77 ± 0.40 and 0.83 ± 0.61 ng/mL), and higher than upper normal level of 0.5 ng/mL. The levels of IL-2 and IL-10 decreased and the levels of IL-1 and TNF-α increased. Post-HD PCT correlated with PTH, IL-1, IL-2, and IL-10. About 60% of patients had elevated PCT levels, HD with low-flux PSN membrane did not change serum PCT and IL-6. While IL-1 and TNF-α increased, IL-2 and IL-10 decreased by PSN membrane during HD. So that PCT levels can be measured just after HD as do prior to start of HD. Is there any relationship between PCT and PTH? PCT may be important in uremic bone disease. [ABSTRACT FROM AUTHOR]