Purification and characterization of polyphenol oxidase from corn tassel.

In this study, polyphenol oxidase (PPO) from corn tassel  was extracted and partially purified through  (NH4)2SO4 precipitation and gel filtration chromatography. Optimal temperatures for subsrates catechol and 4-methyl catechol were 40 °C and 30 °C, respectively. The optimal pH values were 8.0 for catechol and 6.0 for 4-methyl catechol. Catechol was the most suitible substrate (Km: 3.48 mM, Vmax: 1.0 Abs./ min.). The moleculer mass of PPO was determined as 158 kDa. In this work, sodium azide, ethylenediaminetetraacetic acid (EDTA) and sodium dodecyl sulfate (SDS) were found to inhibit the enzyme activity as 26.6 %,  22.2 % and 12.2 % ratio, respectively. Besides, the effects of carbohydrates such as sucrose, fructose, ribose and glucose on PPO activity were investigated. The enzyme was found to be activated 17 % by fructose and ribose, 16 % by glucose and 4 % by sucrose.

Production and purification of novel thermostable alkaline protease from Anoxybacillus sp. KP1.

In this study, an extracellular novel alkaline protease (EC 3.4.21-24, 99) from a thermophilic and aerobic strain of Anoxybacillus sp. KP1 has been studied. Maximum protease activity was obtained at 50 degC at pH 9.0 after 24 hours of incubation. Among the carbon and nitrogen sources used; the optimum protease production was with soluble starch, maltose, urea and casamino acid. The enzyme was purified by ammonium sulphate precipitation and Sephadex G-75 gel chromatography. Molecular weight of purified enzyme was determined as 106 kDa by SDS-PAGE. Purified protease was stable at 50-60 °C and at pH 9.0 for 1 h. The enzyme activity was increased in the presence of Ca2+, Cu2+, Tween 80 and Triton X-100, however the enzyme activity was inhibited in the presence of Hg2+, ethylene diamine tetra acetic acid (EDTA) and H2O2. Proteolytic activity was completely inhibited by phenyl methyl sulfonyl fluoride (PMSF). The enzyme seems to be a serine alkaline protease. In the presence of detergents, the protease was clearly stable and residual activity was between 73-82%.

Cloning, purification and characterization of a thermostable ß-galactosidase from Bacillus licheniformis strain KG9.

A thermo— and alkalitolerant Bacillus licheniformis KG9 isolated from Taşlıdere hot water spring in Batman/Turkey was found to produce a thermostable β—galactosidase. Phylogenetic analysis showed that the 16S rRNA gene from B. licheniformis strain KG9 was 99.9% identical to that of the genome sequenced B. licheniformis strain DSM 13. Analysis of the B. licheniformis DSM 13 genomic sequence revealed four putative β—galactosidase genes. PCR primers based on the genome sequence of strain DSM 13 were used to isolate the corresponding β—galactosidase genes from B. licheniformis strain KG9. The calculated molecular weights of the β—galactosidases I, II, III, and IV using sequencing data were 30, 79, 74, and 79 kDa, respectively. The genes were inserted into an expression vector and recombinant β—galactosidase was produced in Escherichia coli. Of the four β—galactosidase genes identified in strain KG9, three of them were expressed as active, intracellular enzymes in E. coli. One of the recombinant enzymes, β—galactosidase III, was purified and characterized. Optimal temperature and pH was determined to be at 60 ºC and pH 6.0, respectively. Km was determined to be 1.3 mM and 13.3 mM with oNPG (ortho—nitrophenyl—β—D—galactopyranoside) and lactose as substrates, respectively, and Vmax was measured to 1.96 μmol/min and 1.55 μmol/min with oNPG and lactose, respectively.

Can exposure to manganese and extremely low frequency magnetic fields affect some important elements in the rat teeth?

BACKGROUND: Length and level of exposure to electromagnetic fields (EMFs) is increasing in association with the widespread use of electrical and electronic devices and technological progress. The undesirable effects of extremely low frequency magnetic fields (ELF-MFs) on health have attracted considerable interest. MATERIALS AND METHODS: Sixty-four four-month-old male Wistar rats divided into eight groups of eight rats each were used. Seven groups were exposed to varying dosages of manganese (Mn) and a 50 Hz magnetic field (MF) of approximately 1 mT, while the last group was set aside as the cage control group and not subjected to any procedure. This study was intended to investigate the interactions between the application of MF and Mn and the elements Ca, Zn, Mg, and P thought to be involved in caries, in rat teeth. RESULTS: Levels of Ca, Mg, Zn, and P in the experimental group rats were different to those in the control group. CONCLUSIONS: The results demonstrate that ELF-MF and Mn can have significant effects on levels of elements in rat teeth. Further experimental and epidemiological studies of ELF-MF and Mn are needed in order to evaluate their dental effects.

Aortoenteric fistulas - our experiences with surgeons' nightmare.

BACKGROUND: Aortoenteric fistula (AEF) is a rare medical emergency, but one of the most difficult and threatening complications of gastrointestinal (GI) bleeding. METHODS: A retrospective observational study was performed on patients hospitalised with GI bleeding and a definitive AEF diagnosis. We collected operative reports and medical records of patients operated on with an AEF diagnosis. The literature data and our data were analysed and discussed. RESULTS: We admitted eight patients who were definitively diagnosed with AEF after reviewing our hospital records. All patients were male except one. Their ages ranged from 28 to 82, with a mean of 64. All but two patients had secondary AEF (SAEF). Four SAEF cases had open aortic surgery and three had a history of endovascular procedure. The main complaints of the patients on admission were poor general condition, abdominal pain, and GI bleeding. Melena was found in all patients. Hematemesis and hematochezia were other significant GI bleeding findings. Infected grafts were removed in all but one patient; extra-anatomical bypass surgery and bowel repairs were performed. One patient underwent endovascular repair. In all patients, the 30-day in-hospital mortality rate was 50%. CONCLUSION: In patients presenting with GI bleeding, an aortoenteric fistula should be considered. The outcome depends on early diagnosis, the patient's medical status, the severity of infection, and the anatomic location of the affected aorta. A multidisciplinary approach, appropriate treatment planning and close follow-up after treatment lead to positive outcomes.

Active control of focal length and beam deflection in a metallic nanoslit array lens with multiple sources.

We propose an all-optical method to actively control the transmission of nanoslit arrays for scanning and lensing applications. We show that by utilizing two lateral control slits, the transmitted beam can be actively steered.

Identification of a novel slow-muscle-fiber enhancer binding protein, MusTRD1.

The molecular mechanisms which are responsible for restricting skeletal muscle gene expression to specific fiber types, either slow or fast twitch, are unknown. As a first step toward defining the components which direct slow-fiber-specific gene expression, we identified the sequence elements of the human troponin I slow upstream enhancer (USE) that bind muscle nuclear proteins. These include an E-box, a MEF2 element, and two other elements, USE B1 and USE C1. In vivo analysis of a mutation that disrupts USE B1 binding activity suggested that the USE B1 element is essential for high-level expression in slow-twitch muscles. This mutation does not, however, abolish slow-fiber specificity. A similar analysis indicated that the USE C1 element may play only a minor role. We report the cloning of a novel human USE B1 binding protein, MusTRD1 (muscle TFII-I repeat domain-containing protein 1), which is expressed predominantly in skeletal muscle. Significantly, MusTRD1 contains two repeat domains which show remarkable homology to the six repeat domains of the recently cloned transcription factor TFII-I. Furthermore, both TFII-I and MusTRD1 bind to similar but distinct sequences, which happen to conform with the initiator (Inr) consensus sequence. Given the roles of MEF2 and basic helix-loop-helix (bHLH) proteins in muscle gene expression, the similarity of TFII-I and MusTRD1 is intriguing, as TFII-I is believed to coordinate the interaction of MADS-box proteins, bHLH proteins, and the general transcription machinery.

Treatment of chronic type B aortic dissection by endovascular grafting in a previously CABG patient. Case report.

High mortality rates resulting from the surgical treatment of Type B aortic dissections have played an important role in seeking newer alternative therapy modalities for the treatment of the pathology. Especially since the early 1990s, endovascular grafting has become a popular option in the treatment of aortic diseases and with the increasing experience and advances in technology, it has, in recent years, become an alternative approach for the treatment of aortic dissections. In this report, we present the treatment of a 56-year-old male patient with a history of a coronary artery bypass grafting who presented with chronic type B aortic dissection. Endovascular stent graft implantation was performed with a hybrid therapy type of preliminary right subclavian artery to left subclavian artery bypass, followed by endovascular stent graft implantation to the dilated aneurismal segment of the descending aorta, for the treatment of chronic type B aortic dissection. The procedure and the postoperative course were uneventful; moreover, they were very comfortable for the patient undergoing an investigation of the descending aorta, when compared with the conventional surgical treatment modalities.

Case report: Foreign body granuloma mimicking liver metastasis.

In this study, foreign body granuloma mimicking liver metastasis diagnosed on routine follow-up examination in a 41-year-old woman with rectal adenocarcinoma is reported. To our knowledge, this is the first study in English-language literature reporting foreign body granuloma indistinguishable from liver metastasis on radiological examination.

Integration of Biological Control Agents and Systemic Acquired Resistance Inducers Against Bacterial Spot on Tomato.

Two strains of plant growth-promoting rhizobacteria, two systemic acquired resistance inducers (harpin and acibenzolar-S-methyl), host-specific unformulated bacteriophages, and two antagonistic bacteria were evaluated for control of tomato bacterial spot incited by Xanthomonas campestris pv. vesicatoria in greenhouse experiments. Untreated plants and plants treated with copper hydroxide were used as controls. The plant growth-promoting rhizobacteria or a tap water control were applied as a drench to the potting mix containing the seedlings, while the other treatments were applied to the foliage using a handheld sprayer. The plant growth-promoting rhizobacteria strains, when applied alone or in combination with other treatments, had no significant effect on bacterial spot intensity. Messenger and the antagonistic bacterial strains, when applied alone, had negligible effects on disease intensity. Unformulated phage or copper bactericide applications were inconsistent in performance under greenhouse conditions against bacterial spot. Although acibenzolar-S-methyl completely prevented occurrence of typical symptoms of the disease, necrotic spots typical of a hypersensitive reaction (HR) were observed on plants treated with acibenzolar-S-methyl alone. Electrolyte leakage and population dynamics experiments confirmed that acibenzolar-S-methyl-treated plants responded to inoculation by eliciting an HR. Application of bacteriophages in combination with acibenzolar-S-methyl suppressed a visible HR and provided excellent disease control. Although we were unable to quantify populations of the bacterium on the leaf surface, indirectly we determined that bacteriophages specific to the target bacterium reduced populations of a tomato race 3 strain of the pathogen on the leaf surface of acibenzolar-S-methyl-treated plants to levels that did not induce a visible HR. Integrated use of acibenzolar-S-methyl and phages may complement each other as an alternative management strategy against bacterial spot on tomato.

Prediction of bone marrow involvement in patients with malignant lymphoma by GM-CSF stimulation test.

Recently, a stimulation test with colony stimulation factors was found useful to predict bone marrow cellularity. We examined the usefulness of this test to predict the bone marrow involvement in patients with malignant lymphoma. A single dose of GM-CSF (5 micrograms/kg) was given subcutaneously to 12 patients with malignant lymphoma. Six patients had normocellular bone marrow. Five of these 6 patients showed an increase in neutrophils of more than 5 x 10(9)/l after GM-CSF administration. The remaining 6 patients who had bone marrow lymphoma involvement had a neutrophil count of less than 5 x 10(9)/l. Therefore, the change in neutrophil count with a cut-off value of 5 x 10(9)/l distinguished the marrow lymphoma involvement with a sensitivity and specificity of 83% and 100%, respectively. The nadir neutrophil count was significantly higher in patients with normal marrow than in patients with marrow involvement after chemotherapy (P < 0.02). In conclusion, the GM-CSF stimulation test is useful to predict the marrow involvement in patients with malignant lymphoma.

The correlation equations for the assays of heparin in metachromatic and thrombin time methods. I.

The subject of parallelism by metachromatic and biological assay results was examined. New correlation equations were proposed firstly between metachromatic and thrombin time assays with heparin units, secondly between metachromatic and thrombin time assays.

Cisplatin and carboplatin combination as second-line chemotherapy in dacarbazine-resistant melanoma patients.

High-dose cisplatin regimens have been shown to be highly active in advanced melanoma patients but are associated with unacceptable side effects. In order to increase the platinum dose but avoid severe side effects, we treated 15 dacarbazine (DTIC)-resistant metastatic melanoma patients with a combination regimen of cisplatin (100 mg/m2) and carboplatin (200 mg/m2), two platinum analogues with a similar mode of action but a different toxicity pattern. After a mean follow-up period of 10.7 months (range 4-18 months), two patients (13.3%) achieved complete remission and two patients (13.3%) showed partial remission, giving an overall response rate of 26.4% (95% confidence interval [CI] 4.2-49%). Furthermore, three patients (20%; 95% CI 0-40.2%) experienced stable disease. The median duration of response was 7.1 months (95% CI 4.2-10.0 months), and the median overall survival was 12.5 months (95% CI 5.8-19.2 months), with eight patients still alive. The main side effects were haematological (leukopenia/thrombocytopenia World Health Organization [WHO] grade I-IV; anaemia WHO grade I-III), gastrointestinal (WHO grade I-III), neurological (WHO grade I-II) and renal (WHO grade I) toxicity. Nevertheless, except in one patient, side effects did not result in discontinuation of therapy. Despite the small number of patients treated in this preliminary study, we believe that combining cisplatin and carboplatin represents a novel, active and well-tolerated therapeutic option as second-line chemotherapy in DTIC-resistant advanced melanoma patients.

The accumulation and histological effects of organometallic fungicides Propineb and Maneb in the kidneys of fetus and female rats during pregnancy.

Dithiocarbamate propineb and maneb are organometal fungicides, which are widely used for the control of diseases in plants. Female Wistar rats were exposed orally to 200 and 400 ppm propineb and 250 ppm maneb, from the sixth day of gestation up to birth. We found that the body weights of both one-day old litters and their fungicide-treated mothers were lower than those of controls. Histological examination of the kidneys of fetus and fungicide-treated pregnant females showed a variety of histopathological effects. Moreover, the analysis of zinc (Zn) and manganese (Mn) concentrations (using inductively coupled plasma-atomic emission spectrometry) in the kidneys of pregnant females exposed to organometallic fungicides during pregnancy demonstrated that the metal concentrations in the kidney were higher than those of controls. However, the renal metal concentrations were significantly increased in the litters subjected to the fungicides during gestation, indicating that high levels of the trace metals in the organ of fetus may well be due to the fungicides easily passing the placental barrier.

Synthesis and antimicrobial activities of some 3-arylamino-5-[2-(substituted 1-imidazolyl)ethyl]-1,2,4-triazole derivatives.

In this study, some 3-arylamino-5-[2-(substituted imidazol-1-yl or benzimidazol-1-yl)ethyl]-1,2,4-triazole derivatives were synthesised by reacting 3-(substituted imidazol-1-yl)propionyl hydrazides, with S-methyl-N'-arylisothiouronium iodide salts. Their structures were elucidated by IR, 1H-NMR and mass spectroscopic data and elemental analyses results. Antimicrobial activities of the compounds were observed against Staphylococcus aureus NRRL B-767, Micrococcus luteus NRRL B-4375, Escherichia coli B, Pseudomonas aeroginosa NRRL B-23 and the fungi Candida albicans and Candida glabrata by using the tube dilution technique. Remarkable activity was obtained.

Calcium moderation of cadmium stress explored using a stress-inducible transgenic strain of Caenorhabditis elegans.

In a transgenic strain of Caenorhabditis elegans carrying a stress-inducible lacZ reporter gene, short-term sublethal exposure to heavy metals activates transgene expression. The transgene response to Cd2+ is strongly inhibited by Ca2+ ions; furthermore, Ca2+ reduces the net accumulation of Cd2+ by worms. Both Ca2+ and a variety of calcium uptake inhibitors (nifedipine, La3+, verapamil) depress the dose response of the transgene to Cd2+. Calcium ionophore (A23187) slightly increases transgene activity in control and Cd2+ treated worms, but has a much larger effect in the case of Mn2+, reflecting its much greater affinity for this ion.

Heavy metal monitoring of marine algae from the Turkish Coast of the Black Sea, 1998-2000.

Concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined in macroalgae samples collected from the Turkish Coast of the Black Sea. Certain algae species were chosen among the green, brown and red algae species at Sile and Sinop sampling stations from 1998 to 2000. In general, as regards the influence of the collection sites on the whole metal accumulation, Sinop is considered to be more polluted than Sile. The concentrations of the heavy metals in Cystoseira barbata algae are compared with previous studies in the same stations. The results showed that all metal levels have gradually decreased during past years. At the same time, Cd, Co, Cr, Cu, Fe, Ni and Pb levels in the present study are lower than in Bosphorus and Marmara Sea algae. However, Mn and Zn concentrations are higher than Bosphorus but lower than at Marmara. According to these findings the heavy metal pollution decreased in Turkish Coast of the Black Sea during the years investigated.

The accumulation and histological effects of organometallic fungicides propineb and maneb in the livers of pregnant rats and their offspring.

Dithiocarbamate propineb and maneb are organometal fungicides, which are widely used for the control of diseases in plants. Female Wistar rats were exposed orally to 200 and 400 ppm propineb (Zn-containing dithiocarbamate) and 250 ppm maneb (Mn-containing dithiocarbamate), from the 6th day of gestation up to birth. We found that the body weights of both newborn litters and their fungicide-treated mothers were lower than those of controls. Histological examination of the livers of fungicide-treated pregnant females and the offspring showed a variety of histopathological effects. Moreover, the analysis of Zn and Mn concentrations in the livers of pregnant females exposed to organometallic fungicides during pregnancy demonstrated that the metal concentrations in the liver were higher than those of controls. Similarly, the hepatic metal concentrations were significantly increased in the litters, indicating the transplacental passage of the organometallic fungicides.

Anticholinesterase poisoning in Turkey--clinical, laboratory and radiologic evaluation of 269 cases.

A retrospective study was conducted on 269 patients with anticholinesterase poisoning who had been admitted to the Internal Medicine and Pediatric Clinics over the past 10 years. Their ages ranged from 17 d to 62 years. In adults, suicide was the most common means of intoxication. Miosis was the most frequent symptom and was seen in 80.66% of the patients. Hyperglycaemia, hypoglycaemia, hypokalaemia, hyperkalaemia, hyperchloraemia, hypochloraemia and hyponatraemia were among the electrolytic and haematologic disorders (hyperglycaemia 48.00%, hypoglycaemia 6.40%). There were also electrocardiographic abnormalities. Asthma, although usually a late complication, was also noted at the beginning of treatment. Mortality rates were 8.98% for children and 9.6% for adults. Since hypoglycaemia was found in all the patients who died, it was accepted as an ominous prognostic sign. We think that anticholinesterase poisoning is an important health problem in our country. It is much less common in developed than semi-developed countries, and a complete understanding of it is essential for the emergency physician.