Formulation of organic and inorganic hydrogel matrices for immobilization of β‐glucosidase in microfluidic platform

The aim of this study was to formulate silica and alginate hydrogels for immobilization of β‐glucosidase. For this purpose, enzyme kinetics in hydrogels were determined, activity of immobilized enzymes was compared with that of free enzyme, and structures of silica and alginate hydrogels were characterized in terms of surface area and pore size. The addition of polyethylene oxide improved the mechanical strength of the silica gels and 68% of the initial activity of the enzyme was preserved after immobilizing into tetraethyl orthosilicate–polyethylene oxide matrix where the relative activity in alginate beads was 87%. The immobilized β‐glucosidase was loaded into glass–silicon–glass microreactors and catalysis of 4‐nitrophenyl β‐d ‐glucopyranoside was carried out at various retention times (5, 10, and 15 min) to compare the performance of silica and alginate hydrogels as immobilization matrices. The results indicated that alginate hydrogels exhibited slightly better properties than silica, which can be utilized for biocatalysis in microfluidic platforms.     

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Benzothiazepine compounds have a wide range of applications such as antibacterial, antidepressants, anticonvulsants, antihypertensives, antibiotics, antifungal, hypnotic, enzyme inhibitors, antitumor, anticancer and anti‐HIV agents. In this study, the synthesis of novel tetralone‐based benzothiazepine derivatives ( 1–16 ) and their in vitro antibacterial activity and human carbonic anhydrase isoenzymes I and II (hCA I and II) inhibitory effects were investigated. Both isoenzymes were purified by sepharose‐4B‐l ‐tyrosine‐sulfanilamide affinity chromatography from fresh human red blood cells. All compounds demonstrated the low nanomolar inhibitory effects on both isoenzymes using esterase activity. Benzothiazepine derivative 2 demonstrated the best hCA I inhibitory effect with K_i value of 18.19 nM. Also, benzothiazepine derivative 7 showed the best hCA II inhibitory effect with K_i value of 11.31 nM. On the other hand, acetazolamide clinically used as CA inhibitor, showed K_i value of 19.92 nM against hCA I and 33.60 nM against hCA II, respectively.     

AZF microdeletions on the Y chromosome of infertile men from Turkey

Intervals V and VI of Yq11.23 regions contain responsible genes for spermatogenesis, and are named as "azoospermia factor locus" (AZF). Deletions in these genes are thought to be pathogenetically involved in some cases of male infertility associated with azoospermia or oligozoospermia. The aim of this study was to establish the prevalence of microdeletions on the Y chromosome in infertile Turkish males with azoospermia or oligozoospermia. We applied multiplex polymerase chain reaction (PCR) using several sequence-tagged site (STS) primer sets, in order to determine Y chromosome microdeletions. In this study, 61 infertile males were enrolled for the molecular AZF screening program. In this cohort, one infertile male had 46,XX karyotype and the remaining had 46,XY karyotypes. Forty-eight patients had a diagnosis of azoospermia and 13 had oligozoospermia. Microdeletions in AZFa, AZFb and AZFc (DAZ gene) regions were detected in two of the 60 (3.3%) idiopathic infertile males with normal karyotypes and a SRY translocation was determined on 46,XX male. Our findings suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.     

Na+/I− Symporter and Type 3 Iodothyronine Deiodinase Gene Expression in Amniotic Membrane and Placenta and Its Relationship to Maternal Thyroid Hormones

Placental type 3 iodothyronine deiodinase (D3) potentially protects the fetus from the elevated maternal thyroid hormones. Na⁺/I^? symporter (NIS) is a plasma membrane glycoprotein, which mediates active iodide uptake. Our objectives were to establish the distribution of NIS and D3 gene expressions in the placenta and the amniotic membrane and to investigate the relationship between placental D3 and NIS gene expressions and maternal iodine, selenium, and thyroid hormone status. Thyroid hormones, urinary iodine concentration (UIC), and selenium levels were measured in 49 healthy term pregnant women. NIS and D3 gene expressions were studied with the total mRNA RT-PCR method in tissues from maternal placenta (n?=?49), fetal placenta (n?=?9), and amniotic membrane (n?=?9). NIS and D3 gene expressions were shown in the fetal and maternal sides of the placenta and amniotic membrane. Mean blood selenium level was 66?±?26.5 μg/l, and median UIC was 143 μg/l. We could not demonstrate any statistically significant relationship of spot UIC and blood selenium with NIS and D3 expression (p?>?0.05). Positive correlations were found between NIS and thyroxine-binding globulin (TBG) (r?=?0.3, p?=?0.042) and between D3 and preoperative glucose levels (r?=?0.4, p?=?0.006). D3 and NIS genes are expressed in term placenta and amniotic membrane; thus, in addition to placenta, amniotic membrane contributes to regulation of maternofetal iodine and thyroid hormone transmission. Further studies are needed to clarify the relationship between maternal glucose levels and placental D3 expression and between TBG and placental NIS expression.     

Effect of Inoculation with Non-indigenous and Indigenous Rhizobacteria of Erzurum (Turkey) Origin on Growth and Yield of Spring Barley

Two experiments were performed to examine the effects of inoculation of barley cv. Tokak 157/37 with indigenous and non-indigenous bacterial strains. A greenhouse experiment was carried out with 75 strains isolated from Erzurum Plain and Pasinler Plain soils of Turkey, and the 6 non-indigenous strains. The 41 strains had significant positive effects on tiller number per plant, 8 strains on plant height, one strain on dry matter yield, and 24 strains on plant protein concentration. In the second experiment, the response of barley to 20 treatments (9 indigenous strains, 6 non-indigenous strains, 4 levels of N, and a control) was investigated in Erzurum Agricultural Experiment field in 2000 and 2001. Inoculation with certain indigenous and non-indigenous strains clearly benefited growth and increased the yield of field grown barley. On average of years, inoculation with Strain No. 19, Strain No. 39, Strain No. 73, Strain No. 82, BA-7, BA-142 and M-13 increased total biomass by 29.4–15.1%, grain yield by 26.6–17.7%, and total N-yield by 32.7–20.6%, as compared to the control. Indigenous Strain No. 19 was superior to all other treatments in terms of grain yield and N-yields. The higher efficacy of combining Strain No. 19 and Tokak 157/37 indicates the possibility of improved associations using olden and common cultivar and indigenous bacteria. In conclusion, Strain No. 19 seems to be suitable inoculant for barley cultivation in areas such as in Erzurum conditions.     

Interstitial Lung Disease in Coppersmiths in High Serum Copper Levels

Coppersmith is a worker who uses copper most commonly for the production of kitchen appliances in Turkey. This is an ancient occupation practiced for centuries in Turkey. Our objective was to investigate the prevalence of parenchymal lung diseases among coppersmiths in Kahramanmaras city in Turkey. Thirty coppersmiths were included to the study, and they all signed an informed consent. Demographics, spirometric test results and high-resolution computed tomography (HRCT) scans, and blood samples were obtained. Laboratory analysis of the serum samples showed that serum copper levels of the subjects were 0.93 ± 0.14 mg/L. Serum copper level in control group was found as 0.70 ± 0.14 mg/L, and it was significantly different between the two groups (p < 0.05). Of 30 coppersmiths, 17 HRCT findings are abnormal and seen with diffuse parenchymal interstitial lung disease pattern—ten (58.8%) respiratory bronchiolitis interstitial lung disease, five (29.4%) nonspecific interstitial pneumonia, and two (11.8%) usual interstitial pneumonia. The most prevalent HRCT pattern was micronodular pattern in workers. This is the first field study reporting the radiologic findings of coppersmiths and effect of the occupation on lung diseases.     

Morphological assessment of Co2-laser fusion using a flexible light guide in lymphovenous and venovenous anastomoses in experimental animals

In experiments on 13 mongrel dogs with CO2 laser supplied with flexible fiber guide there were formed 17 lympho-venous and 4 veno-venous anastomosis. There were no inadequate sealing, narrowing or aneurysm of the anastomosis. Histopathologic investigations after 3, 6-8, 13-16 days and 1 year showed that vascular walls were positioned correctly. Endothelial surface has continuous character both along the vessel as anastomosis line.     

Daily Variations in the Responses to Papaverine but not Theophylline in Rat Aorta

The presence of temporal patterns in the responses of vascular smooth muscle to relaxing agents have been known. The aim of this study was to examine the variations in the in vitro sensitivity of rat aorta to papaverine and theophylline in both endothelium-intact and -denuded rings. The animals were synchronized with a 12-h light: 12-h dark schedule. Rat thoracic aorta rings were obtained from animals sacrificed at six different times (09:00, 13:00, 17:00, 21:00, 01:00 and 05:00) of the day. Tissues were precontracted submaximally with phenylephrine and then were relaxed by papaverine (10^?8 ? 10^?4 M) and theophylline (10^?7 ? 10^?3 M) applied cumulatively. The responses to most of the concentrations and EC₅₀ values for papaverine demonstrated an ultradian rhythm with an 8 h periodicity. Time-dependent variations were not found in the responses to theophylline. The results are discussed in relation with the time-dependent differences in signal transducing mechanisms.