Optimization of a solid culture medium based on Monochamus alternatus for Cordyceps militaris fruiting body formation

Monochamus alternatus (Coleoptera: Cerambycidae; M. alternatus), popularly known as the Japanese pine sawyer, is a vector of pinewood nematode (Bursaphelenchus xylophilus) that causes pine wilt disease. A solid medium culture with M. alternatus produced Cordyceps militaris fruiting bodies with the longest strips and the highest biological efficiency. Supplementing the original form of M. alternatus with oats resulted in slightly enhanced fruiting body production. The original form of M. alternatus showed higher production than its powder form. The solid culture medium was optimized using a response surface methodology, and the optimal medium contained the following: 8·5 g per bottle of M. alternatus and 11·5 g per bottle of oats mixed with 22·4 ml of water in a 300-ml cylindrical plastic bottle. The optimal culturing period for the fruiting body formation was 37·1 days. Under these conditions, a fruiting body dry weight of 38·0 g per bottle (actual value) was attained. The fruiting body produced using a solid culture medium based on M. alternatus had a cordycepin content of about 25 µg g^-1 . The solid culture medium containing M. alternatus is highly efficient and eco-friendly, and its effectiveness in large-scale fruiting body production from C. militaris has been demonstrated.

[ Ⅲ ]

Objective: To compare the efficacy and safety of Changsulin^® with Lantus^® in treating patients with type 2 diabetes mellitus (T2DM). Methods: This was a phase Ⅲ, multicenter, randomized, open-label, parallel-group, active-controlled clinical trial. A total of 578 participants with T2DM inadequately controlled on oral hypoglycemic agents were randomized 3∶1 to Changsulin^® or Lantus^® treatment for 24 weeks. The efficacy measures included changes in glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG), 2h postprandial plasma glucose (2hPG), 8-point self-monitoring of blood glucose (SMBG) profiles from baseline, and proportions of subjects achieving targets of HbA1c and FPG. The safety outcomes included rates of hypoglycemia, adverse events (AEs) and anti-insulin glargine antibody. Results: After 24 weeks of treatment, mean HbAlc decreased 1.16% and 1.25%, FPG decreased 3.05 mmol/L and 2.90 mmol/L, 2hPG decreased 2.49 mmol/L and 2.38 mmol/L in Changsulin^® and in Lantus^®, respectively. No significant differences could be viewed in above parameters between the two groups (all P>0.05). There were also no significant differences between Changsulin^® and Lantus^® in 8-point SMBG profiles from baseline and proportions of subjects achieving the targets of HbA1c and FPG (all P>0.05). The rates of total hypoglycemia (38.00% and 39.01% for Changsulin^® and Lantus^®, respectively) and nocturnal hypoglycemia (17.25% and 16.31% for Changsulin^® and Lantus^®, respectively) were similar between the two groups (all P>0.05). Most of the hypoglycemia events were asymptomatic, and no severe hypoglycemia were found in both groups. No differences were observed in rates of AEs (61.77% vs.52.48%) and anti-insulin glargine antibody (after 24 weeks of treatment, 6.91% vs.3.65%) between the two groups (all P>0.05). Conclusions: Changsulin^® shows similar efficacy and safety profiles compared with Lantus^® and Changsulin^® treatment was well tolerated in patients with T2DM.

Kirigami-based Elastic Metamaterials with Anisotropic Mass Density for Subwavelength Flexural Wave Control

A novel design of an elastic metamaterial with anisotropic mass density is proposed to manipulate flexural waves at a subwavelength scale. The three-dimensional metamaterial is inspired by kirigami, which can be easily manufactured by cutting and folding a thin metallic plate. By attaching the resonant kirigami structures periodically on the top of a host plate, a metamaterial plate can be constructed without any perforation that degrades the strength of the pristine plate. An analytical model is developed to understand the working mechanism of the proposed elastic metamaterial and the dispersion curves are calculated by using an extended plane wave expansion method. As a result, we verify an anisotropic effective mass density stemming from the coupling between the local resonance of the kirigami cells and the global flexural wave propagations in the host plate. Finally, numerical simulations on the directional flexural wave propagation in a two-dimensional array of kirigami metamaterial as well as super-resolution imaging through an elastic hyperlens are conducted to demonstrate the subwavelength-scale flexural wave control abilities. The proposed kirigami-based metamaterial has the advantages of no-perforation design and subwavelength flexural wave manipulation capability, which can be highly useful for engineering applications including non-destructive evaluations and structural health monitoring.

Prevalence of Asian fish tapeworm Bothriocephalus in grass carp in Dongting Lake of Hunan province, subtropical China

We investigated the prevalence of Asian fish tapeworm Bothriocephalus infection in grass carp in Dongting Lake of Hunan province, subtropical China between August 2014 and October of 2015. A total of 2534 fish samples from four representative administrative regions in Hunan province, subtropical China were examined for the presence of Bothriocephalus using helminthological approach. The overall prevalence of Bothriocephalus in grass carp was 6.6% (167/2534). The prevalence of Bothriocephalus in grass carp was higher in summer (10.0%) and spring (7.0%) than in autumn (6.0%) and winter (3.3%) (P<0.01). The highest prevalence of Bothriocephalus was found in grass carp with body weight 0.5<Weight<1.5 group with 1-91 infected intensity. The highest intensity of infection was in summer (23-104), and least in winter (1-32). The present survey revealed the prevalence of Bothriocephalus in grass carp in Dongting Lake of Hunan province, subtropical China. To our knowledge, this is the first report of Bothriocephalus prevalence in grass carp in China.

Reference of Temperature and Time during tempering process for non-stoichiometric FTO films

In order to enhance the mechanical strength of Low-E glass, Fluorine-doped tin oxide (FTO) films have to be tempered at high temperatures together with glass substrates. The effects of tempering temperature (600 °C ~ 720 °C) and time (150 s ~  300 s) on the structural and electrical properties of FTO films were investigated. The results show all the films consist of non-stoichiometric, polycrystalline SnO2 without detectable amounts of fluoride. 700 °C and 260 s may be the critical tempering temperature and time, respectively. FTO films tempered at 700 °C for 260 s possesses the resistivity of 7.54 × 10(-4) Ω • cm, the average transmittance in 400 ~ 800 nm of ~80%, and the calculated emissivity of 0.38. Hall mobility of FTO films tempered in this proper condition is mainly limited by the ionized impurity scattering. The value of [O]/[Sn] at the film surface is much higher than the stoichiometric value of 2.0 of pure crystalline SnO2.

Effect of co-existing copper and calcium on the removal of As(V) by reused aluminum oxides

Among the various heavy metals, arsenic is frequently found in abandoned mine drainage and the environmental fate of arsenic in real aqueous solutions can be highly dependent on the presence of co-existing ions. In this study, removal of arsenate through adsorption on the reused aluminum oxide or through precipitation was investigated in a single and in a binary system as a function of pH and concentration. Different removal behaviors of arsenate were observed in the presence of different cations as well as a variation of the molar ratios of arsenate to cations. Co-operative effects on arsenate removal by precipitation in solution occurred with an increase of copper concentration, while a decrease of arsenate removal resulted in increasing calcium concentration. It was observed that the arsenate removal in the presence of calcium would be highly dependent on the molar ratios of both elements.

Effect of different types of organic compounds on the photocatalytic reduction of Cr(VI)

The effect of different types of organic compounds (humic acid, oxalate, ethylenediaminetetraacetic acid, nitrilotriacetic acid, phenol) on the photocatalytic reduction of Cr(VI) with illuminated TiO2 was studied in this work with variation of the solution pH, contact time, initial Cr(VI) concentration and type of organic compounds. As the pH increased, the removal efficiency for Cr(VI) decreased. The increase in Cr(VI) removal by UV/TiO2 with decreasing solution pH was due to the increased potential difference between the conduction band of TiO2 and Cr(VI)/Cr(III) as well as the anionic-type adsorption of Cr(VI) on to the TiO2 surface. Removal efficiency for Cr(VI) increased in the presence of organic compound compared with that without organic compound because positive holes in the TiO2 were scavenged by organic additives. The reduction pattern of Cr(VI) was better described by the first-order kinetic model. Finally photocatalytic reaction with illuminated TiO2 can be effectively applied to treat wastewater contaminated with Cr(VI).

Magnetic resonance imaging retinal oximetry: a quantitative physiological biomarker for early diabetic retinopathy?

AIMS

To assess the efficacy of using magnetic resonance imaging measurements of retinal oxygenation response to detect early diabetic retinopathy in patients with Type 2 diabetes.

METHODS

Magnetic resonance imaging was conducted during 100% oxygen inhalation in patients with Type 2 diabetes with either no diabetic retinopathy (n = 12) or mild to moderate background diabetic retinopathy (n = 12), as well as in healthy control subjects (n = 12). Meanwhile, changes in retinal oxygenation response were measured.

RESULTS

In the healthy control group, levels of retinal oxygenation response increased slowly during 100% oxygen inhalation. In contrast, they increased more quickly and attained homeostasis much earlier in the groups with background diabetic retinopathy (at the 20-min time point) and with no diabetic retinopathy (at the 25-min time point) than in the healthy control group (at the 42-min time point). Furthermore, levels of retinal oxygenation response in the group with background diabetic retinopathy increased more than that of the group with no diabetic retinopathy, which in turn increased more than that of the healthy control group. There are statistically significant differences between the group with background diabetic retinopathy and the healthy control group at 6-, 8-, 10-, 15-, 20- and 25-min time points (P < 0.05). According to the normal range of the healthy control group by setting fundus photography results as 'gold standard' in our research, the sensitivity, specificity, positive predictive value, negative predictive value and receiver operating characteristic area for reporting the early indications of utility of diabetic retinopathy were 83.33%, 58.33%, 50%, 87.5% and 0.774, respectively.

CONCLUSIONS

The results indicate that magnetic resonance imaging is a potential screening method and probably a quantitative physiological biomarker to find early diabetic retinopathy in patients with Type 2 diabetes.

Photocatalytic reduction of Cr(VI) and Ni(II) in aqueous solution by synthesized nanoparticle ZnO under ultraviolet light irradiation: a kinetic study

Photocatalytic removal of Cr(VI) and Ni(II) from aqueous solution using synthesized nanoparticle ZnO under ultraviolet (UV) light irradiation was studied in this work. Firstly, nanoparticle ZnO was prepared by the chemical method with an organic chemical inhibitor. Then removal efficiency of Cr(VI) and Ni(II) by nanoparticle ZnO was investigated with variation of the solution pH, ZnO dosage, contact time and initial Cr(VI) and Ni(II) concentration. Maximum removal of Cr(VI) and Ni(II) was observed at near-neutral pH because the reduced photocatalytic activity of ZnO at exceedingly low and high pH values originates from either acidic/photochemical corrosion of the catalyst and/or surface passivation with Zn(OH)2. As the ZnO dosage increased, the removal efficiency of Cr(VI) and Ni(II) was continuously enhanced, but was gradually decreased above 1.25 g/l due to the increased blockage of the incident UV light used for the photocatalytic reaction. The optimum ZnO dosage was determined as 1 g/l. Removal efficiencies of Cr(VI) and Ni(II) decreased as initial Cr(VI) and Ni(II) concentration increased, due to an increased inhibition effect on the surface of ZnO resulting from the decreased reaction sites on the surface of ZnO required for the further photocatalytic reaction.

Tissue-specific pattern of angiotensin-converting enzyme 2 expression in rat pancreas

Angiotensin-converting enzyme 2 (ACE2), a carboxypeptidase that is highly homologous to ACE, acts as a negative regulator for the renin-angiotensin system (RAS). Pancreatic RAS is thought to play important endocrine and exocrine roles in hormone secretion. Further exploration of this system is likely to offer new insights into the pathogenesis of pancreatic diseases such as diabetes mellitus. This study investigated the expression of ACE2 in rat pancreatic exocrine and endocrine tissue. Reverse transcription-polymerase chain reaction, immunoblotting and immunohistochemistry showed that ACE2 mRNA and protein were expressed in the pancreas. Immunoelectron microscopy demonstrated that ACE2 was expressed in both endocrine and exocrine pancreatic tissues. In the endocrine tissue, ACE2 was localized on the secretory granules. Double immunofluorescence labelling showed that ACE2 was co-localized with both insulin and somatostatin, while it was rarely co-localized with glucagon and pancreatic polypeptide. These findings suggest that ACE2 might play an important role in glucose homeostasis.

Cloning and phylogenetic analysis of the chitinase gene from the facultative pathogen Paecilomyces lilacinus

AIMS

To PCR-amplify the full-length genomic-encoding sequence for one chitinase from the facultative fungal pathogen Paecilomyces lilacinus, analyse the DNA and deduced amino acid sequences and compare the amino acid sequence with chitinases reported from mycopathogens, entomopathogens and nematopathogens.

METHODS AND RESULTS

The encoding gene (designated as PLC) was isolated using the degenerate PCR primers and the DNA-Walking method. The gene is 1458 bp in length and contains three putative introns. A number of sequence motifs that might play a role in its regulation and function had also been found. Alignment of the translation product (designated as Plc, molecular mass of 45.783 kDa and pI of 5.65) with homologous sequences from other species showed that Plc belongs to Class V chitinase within the glycosyl hydrolase family 18. The phylogenetic and molecular evolutionary analysis using mega (Molecular Evolutionary Genetics Analysis) indicated that these chitinases from mycopathogens, entomopathogens and nematopathogens, the majority of which belong to glycosyl hydrolase family 18, were clustered into two well-supported subgroups corresponding to ascomycetes fungal and nonfungal chitinases (bacteria, baculoviruses).

CONCLUSIONS

Our study showed that chitinases from mycoparasitic, entomopathogenic and nematophagous fungi are closely related to each other and reaffirmed the hypothesis that baculovirus chitinase is most likely to be of a bacterial origin - acquired by gene transfer. Bacterial and baculoviral chitinases in our study are potential pathogenicity factors; however, we still cannot ascribe any specific function to those chitinases from the fungi.

SIGNIFICANCE AND IMPACT OF THE STUDY

To our knowledge, this is the first report describing the chitinase gene and its translation product from Paecilomyces lilacinus, which constitutes the largest number of formulated biological nematicides reported so far, this is also the first study to analyse and resolve the phylogenetic and molecular evolutionary relationships among the chitinases produced by mycopathogens, entomopathogens and nematopathogens.

Applicability of reused industrial dry sanding powder for adsorption of arsenic

This study examined the potential reuse of powdered wastes (PW) generated during the sanding and sawing process in a local chemical company in Korea with the viewpoint of the recycling these wastes and minimizing the level of contamination. As the aluminium hydroxide inside the PW could be thermally converted to various types of aluminium oxides depending on the calcination temperature, the adsorptive properties could be changed and it may affect on adsorption ability. Calcination of the PW was performed for 3 h at 550 degrees C, 750 degrees C, and 950 degrees C. From the results, amorphous aluminium oxide was thermally generated by calcinating the PW at 550 degrees C and with further increase of temperature to 950 degrees C, the crystallinity of amorphous aluminium oxide was gradually increased. The physicochemical analysis of calcined powdered wastes (CPW) at various temperatures showed that more developed porosity was noted in the CPW as the calcinations temperature increased, whereas surface area was significantly decreased from 175.5 m2 g(-1) to 46.5 m2 g(-1). The removal efficiency of arsenate on the CPW decreased as the calcinations temperature increased from 550 degrees C to 950 degrees C. The CPW550 exhibited the highest adsorption capacities toward arsenate over pH range of 2-8 and showed a complete removal of the arsenate (10.0 mg L(-1)) within the first 10 min. Adsorption kinetic studies showed that the rate of arsenic adsorption on the CPW decreased with the increase of the calcination temperature. When the maximum adsorption capacity of arsenic onto the CPW was calculated by Langmuir equation, the CPW550 has the highest value as 43.9 mg g(-1).

Arsenic removal by iron and manganese coated sand

In this study, as a promising technique for the treatment of both As(III) and As(V) at the same time in a single reactor, a column reactor containing both manganese-coated sand (MCS) and iron-coated sand (ICS), at different configuration of MCS and ICS, was used to treat wastewater contaminated with As(III). Prior to column experiments, batch experiments for the adsorption of As(V) by ICS were performed with variation of solution pH, ionic strength and types of background ions to investigate the effect of these parameters on the As(V) adsorption behaviour. As(V) adsorption onto ICS was quite similar with the variation of ionic strength by using NaNO3 as a background ion as well as in the presence of different types of background ions except phosphate. The adsorption curves shifted to the lower pH region with the increase of the initial arsenic concentration due to the finite number of adsorption sites on the ICS. For model prediction on the adsorption of As(V) onto ICS, the MINEQL program employing an inner-sphere complexation and a diffuse layer model was used. Model predictions generally agreed well with experimental results. From the column test, column system packed with equal ratio of MCS and ICS was identified as the best system due to a promising oxidation efficiency of As(III) to As(V) by MCS and adsorption of As(V) by both MCS and ICS.

Application of iron-coated sand and manganese-coated sand on the treatment of both As(III) and As(V)

In this study, manganese-coated sand (MCS) and iron-coated sand (ICS) were applied in the oxidation of As(III) and adsorption of As(V), respectively. ICS and MCS were prepared by mixing FeCl3 and Mn(NO3)2, respectively, with Joomoonjin sand at 150 degrees C. In the batch adsorption isotherms, adsorption of As(III) and As(V) onto ICS followed a Langmuir type. ICS showed a greater capacity in the removal of As(V) than As(III) and also in the removal of As(V) compared with MCS. Three different configurations of ICS and MCS were used to investigate the oxidation of As(III) and adsorption of As(V) in a column. In the homogenised system, arsenic breakthrough was approximately two-times delayed compared with the separately packed systems. After breakthrough of arsenic, concentration of As(III) in the effluents was below 40 ppb for the entire reaction period in all configurations, and most arsenic was identified as As(V) owing to near complete conversion of As(III) to As(V) by MCS. The catalytic activity of MCS on the oxidation of As(III) was maintained up to 700 pore volumes, which corresponds to the treatment of at least 300 mg As(III) based on the 1 kg MCS. Compared with the homogenised column, the released Mn(II) concentration from two-staged and four-staged columns was great for the entire reaction period. In the case where the same amount of ICS and MCS was packed in a filtration system, the homogenised column was identified as a better configuration compared with the two-staged and four-staged columns when considering the arsenic breakthrough time as well as the released concentration of Fe(III) and Mn(II).

Potential application of manganese coated sand in the removal of Mn(II) from aqueous solutions

The aim of this study was to explore the applicability of manganese coated sand (MCS) in the presence and absence of sodium hypochlorite for the removal of Mn(II) (2 mg/L) from aqueous solutions. Sand itself is widely used as a filter media for the treatment of wastewaters and it was reported that during the treatment, Mn(II), which is present in the wastewater, is to be deposited on the surface of sand in the form of manganese dioxide. The present investigation dealt with various MCS samples, prepared in the laboratory by various doses of Mn(II) (i.e. from 0.05 to 0.2 mol/L) and the samples were obtained from the pilot plant and naturally coated in the water treatment plant for the removal of Mn(II) in the batch and column studies. Moreover, it was realised that the role of hypochlorite is multifunctional as it not only enhances the uptake of Mn(II) on the surface of MCS through oxidation of Mn(II) into Mn(IV) and hence the formation of manganese dioxide, but it was also supposed to disinfect the bacteria or harmful pathogens from the waste/surface waters. The results obtained clearly inferred that various MCS samples used for the removal of Mn(II) from aqueous solutions showed comparable removal efficiency. However, the presence of sodium hypochlorite greatly enhanced the removal of Mn(II) as more than 80% Mn(II) was removed in the presence of sodium hypochlorite at around pH 6.5. Similarly, while comparing the column data it was again noted that the breakthrough points occurred after the 4,100 and 6,500 bed volumes, respectively, in the absence and in the presence of sodium hypochlorite (2 mg/L).

Removal of toxic heavy metals by iron-coated starfish

In this study, the applicability of calcined starfish (SF) and iron-coated SF (ICSF) as potential adsorbents for the treatment of wastewater containing heavy metal ions was evaluated. ICSF was prepared by mixing FeCl(3) solution previously adjusted to pH 7 approximately 9 with SF at 105 degrees C. From the dissolution test at pH 2, ICSF showed strong acid-proof properties. In the batch adsorption, Cu(II) adsorption onto ICSF was completed within 150 minutes, while 47% Cu(II) was removed with SF alone. This result clearly suggests that the coated Fe(III) serves additional adsorption sites, resulting in the enhanced removal of heavy metal ions. The removed fraction of both Cu(II) and Pb(II) increased with increasing solution pH and nearly complete removals of Pb(II) and Cu(II) were observed at around pH 6 and 8, respectively. From the adsorption isotherm of Cu(II) onto SF and ICSF at pH 3.0, the removed amount of Cu(II) by ICSF was greater than that by SF over the entire concentration range studied. In the column test, the breakthrough of Cu(II) in the ICSF column was greatly retarded compared to that in the SF column. Based on the drinking water regulations for Cu(II), SF and ICSF were able to remove 3400 and 8600 mg/kg of Cu(II) from the wastewater, respectively.

Purification and characterization of an extracellular serine protease from the nematode-trapping fungus Dactylella shizishanna

AIMS

To evaluate the production of an extracellular serine protease by Dactylella shizishanna and its potential as a pathogenesis factor.

METHODS AND RESULTS

An extracellular alkaline serine protease (Ds1) was purified and characterized from the nematode-trapping fungus D. shizishanna using cation-exchange chromatography and hydrophobic interaction chromatography. The molecular mass of the protease was approximately 35 kDa estimated by SDS-PAGE. The optimum activity of Ds1 was at pH 10 and 55 degrees C (over 30 min). The purified protease could degrade purified cuticle of Penagrellus redivivus and a broad range of protein substrates. The purified protease was highly sensitive to phenylmethyl sulfonyl fluoride (PMSF) (0.1 mmol l(-1)), indicating it belonged to the serine protease family. The N-terminal amino acid residues of Ds1 are AEQTDSTWGL and showed a high homology with Aozl and PII, two serine proteases purified from the nematode-trapping fungus Arthrobotrys oligospora.

CONCLUSIONS

Nematicidal activity of D. shizishanna was partly related to its ability to produce extracellular serine protease.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this report, we purified a new serine protease from D. shizishanna and provided a good foundation for future research on infection mechanism.

Plasma glucose levels and diabetes are independent predictors for mortality and morbidity in patients with SARS

AIMS

To investigate the relationships between a known history of diabetes and ambient fasting plasma glucose (FPG) levels with death and morbidity rates in patients with severe acute respiratory syndrome (SARS).

METHODS

In this retrospective analysis, the clinical and biochemical characteristics of 135 patients who had died from SARS, 385 survivors of SARS and 19 patients with non-SARS pneumonia were compared.

RESULTS

All patients were treated according to a predefined protocol. Before steroid treatment, the mean FPG level was significantly higher in the SARS group (deceased vs. survivors vs. non-SARS pneumonia group: 9.7 +/- 5.2 vs. 6.5 +/- 3.0 vs. 5.1 +/- 1.0 mmol/l, P < 0.01). In the SARS group, the percentage of patients with a known history of diabetes was significantly higher in the deceased patients than in the survivors (21.5% vs. 3.9%, P < 0.01). Among patients with no known history of diabetes and before commencement of steroid therapy, those who had hypoxaemia (SaO(2) < 93%) had higher FPG levels than those who did not have hypoxia in both the survivor (8.7 +/- 4.9 vs. 6.3 +/- 2.1 mmol/l, P < 0.001) and deceased (9.8 +/- 4.8 vs. 7.2 +/- 1.5 mmol/l, P < 0.001) groups. A known history of diabetes [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.4, 6.3; P = 0.005] and FPG > or = 7.0 mmol/l before steroid treatment (OR 3.3, 95% CI 1.4, 7.7, P = 0.006) were independent predictors of death. During the course of the illness, FPG levels were negatively associated with SaO(2) (beta =-0.682 +/- 0.305, P = 0.025, general estimation equation model) in SARS patients. Survival analysis showed that FPG was independently associated with an increased hazard ratio (HR) of mortality (HR = 1.1, 95% CI 1.0, 1.1, P = 0.001) and hypoxia (HR = 1.1, 95% CI 1.0, 1.1, P = 0.002) after controlling for age and gender.

CONCLUSIONS

A known history of diabetes and ambient hyperglycaemia were independent predictors for death and morbidity in SARS patients. Metabolic control may improve the prognosis of SARS patients.

Homotypic FADD interactions through a conserved RXDLL motif are required for death receptor-induced apoptosis

Death receptors in the TNF receptor superfamily signal for apoptosis via the ordered recruitment of FADD and caspase-8 to a death-inducing signaling complex (DISC). However, the nature of the protein-protein interactions in the signaling complex is not well defined. Here we show that FADD self-associates through a conserved RXDLL motif in the death effector domain (DED). Despite exhibiting similar binding to both Fas and caspase-8 and preserved overall secondary structure, FADD RDXLL motif mutants cannot reconstitute FasL- or TRAIL-induced apoptosis and fail to recruit caspase-8 into the DISC of reconstituted FADD-deficient cells. Abolishing self-association can transform FADD into a dominant-negative mutant that interferes with Fas-induced apoptosis and formation of microscopically visible receptor oligomers. These findings suggest that lateral interactions among adapter molecules are required for death receptor apoptosis signaling and implicate self-association into oligomeric assemblies as a key function of death receptor adapter proteins in initiating apoptosis.

The TB structural genomics consortium: a resource for Mycobacterium tuberculosis biology

The TB Structural Genomics Consortium is an organization devoted to encouraging, coordinating, and facilitating the determination and analysis of structures of proteins from Mycobacterium tuberculosis. The Consortium members hope to work together with other M. tuberculosis researchers to identify M. tuberculosis proteins for which structural information could provide important biological information, to analyze and interpret structures of M. tuberculosis proteins, and to work collaboratively to test ideas about M. tuberculosis protein function that are suggested by structure or related to structural information. This review describes the TB Structural Genomics Consortium and some of the proteins for which the Consortium is in the progress of determining three-dimensional structures.

A catalogue of molecular, physiological and symbiotic properties of soybean-nodulating rhizobial strains from different soybean cropping areas of China

We have analysed 198 fast-growing soybean-nodulating rhizobial strains from four different regions of China for the following characteristics: generation time; number of plasmids; lipopolysaccharide (LPS), nodulation factors (LCOs) and PCR profiles; acidification of growth medium; capacity to grow at acid, neutral, and alkaline pH; growth on LC medium; growth at 28 and 37 degrees C; melanin production capacity; Congo red absorption and symbiotic characteristics. These unbiased analyses of a total subset of strains isolated from specific soybean-cropping areas (an approach which could be called "strainomics") can be used to answer various biological questions. We illustrate this by a comparison of the molecular characteristics of five strains with interesting symbiotic properties. From this comparison we conclude, for instance, that differences in the efficiency of nitrogen fixation or competitiveness for nodulation of these strains are not apparently related to differences in Nod factor structure.

Competitive photocatalytic oxidation of Cu(II)--EDTA and Cd(II)--EDTA with illuminated TiO2

Competitive photocatalytic oxidation (PCO) of mixtures of Cu(II)-EDTA and Cd(II)-EDTA was studied with variation of molar ratio of these two complexes (1 x 10(-4):0, 8 x 10(-5): 2 x 10(-5), 5 x 10-5:5 x 10(-5), 2 x 10-5:8 x 10(-5), 0:1 x 10(-4) M) and in the pH range of 4-8. PCO rates for each compound can be described using a combined aqueous + adsorbed pathway: -dC/dt = k1Caq(1+ k2Caq)+ kadsCads. This expression is valid under both noncompetitive and competitive conditions. Differences in rates under competition result from differences in the partitioning of the two species between the TiO2 surface and the aqueous phase. Total initial complex degradation rates (rTT), obtained by summation of the total destruction rates for Cu(II)-EDTA and Cd(II)-EDTA, were relatively constant at pH 4 and 5 for all ratios. At these pH values, contribution of adsorbed pathways to rTT was important, and rates were similar to those of the aqueous phase pathways. From pH 6 to 8, the degree of adsorption, and thus the adsorbed pathway rate, diminished. Through the adsorbed pathway, no difference in rate constants was found between Cu(II)-EDTA and Cd(II)-EDTA; Cd(II)-EDTA is somewhat more reactive through the aqueous phase pathway.

Crystallization and preliminary X-ray crystallographic analysis of deoxyuridine triphosphate nucleotidohydrolase from Saccharomyces cerevisiae

Deoxyuridine triphosphate nucleotidohydrolase (dUTPase) from Saccharomyces cerevisiae is essential for cell viability. It has been overexpressed in Escherichia coli and has been crystallized at 296 K using polyethylene glycol (PEG) 1500 as a precipitant. The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 59.48, b = 138.54, c = 157.91 A, alpha = beta = gamma = 90 degrees. Two molecules of trimeric dUTPase from S. cerevisiae are present in the asymmetric unit, giving a crystal volume per protein mass (V(M)) of 3.36 A(3) Da(-1) and a solvent content of 63%. The diffraction limit of the crystals could be significantly extended by the crystal-annealing procedure. A set of native data extending to 2.7 A resolution has been collected at 100 K using synchrotron X-rays.

Intraaortic balloon pump therapy facilitates posterior vessel off-pump coronary artery bypass grafting in high-risk patients

BACKGROUND

Displacement of the heart to expose posterior vessels during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (off-pump CABG, or OPCAB) may impair cardiac function. We used the intraaortic balloon pump (IABP) preoperatively to reduce operative risk and to facilitate posterior vessel OPCAB in high-risk patients with left main coronary artery disease (> 75% stenosis), intractable resting angina, postinfarction angina, left ventricular dysfunction (ejection fraction < 35%), or unstable angina.

METHODS

One hundred and forty-two consecutive patients who underwent multivessel OPCAB including posterior vessel revascularization were studied prospectively. The patients were divided into group I (n = 57), which received preoperative or intraoperative IABP, and group II (n = 85), which did not receive IABP. In group I, there were 34 patients with left main coronary artery disease, 24 patients with intractable resting angina, 8 patients with left ventricular dysfunction, 5 patients with postinfarction angina, and 40 patients with unstable angina. Seven patients received intraoperative IABP support owing to hemodynamic instability during OPCAB.

RESULTS

There was no operative mortality in group I and 1 death in group II. The average number of distal anastomoses was not different between group I and group II (3.4 +/- 0.9 versus 3.5 +/- 0.9, p = not significant). There were no significant differences in the number of posterior vessel anastomoses per patient. There were no differences in ventilator support time, length of stay in the intensive care unit, hospital stay, and morbidity between the two groups. There was one IABP-related complication in group I.

CONCLUSIONS

IABP therapy facilitates posterior vessel OPCAB in high-risk patients, and surgical results are comparable with those in lower-risk patients.

Crystal structure of Escherichia coli CyaY protein reveals a previously unidentified fold for the evolutionarily conserved frataxin family

Friedreich ataxia is an autosomal recessive neurodegenerative disease caused by defects in the FRDA gene, which encodes a mitochondrial protein called frataxin. Frataxin is evolutionarily conserved, with homologs identified in mammals, worms, yeast, and bacteria. The CyaY proteins of gamma-purple bacteria are believed to be closely related to the ancestor of frataxin. In this study, we have determined the crystal structure of the CyaY protein from Escherichia coli at 1.4-A resolution. It reveals a protein fold consisting of a six-stranded antiparallel beta-sheet flanked on one side by two alpha-helices. This fold is likely to be shared by all members of the conserved frataxin family. This study also provides a framework for the interpretation of disease-associated mutations in frataxin and for understanding the possible functions of this protein family.

Crystallization and preliminary X-ray crystallographic analysis of Escherichia coli CyaY, a structural homologue of human frataxin

CyaY is a 106-residue protein from Escherichia coli. It shows amino-acid sequence similarity to human frataxin and a frataxin homologue in Saccharomyces cerevisiae, Yfh1p. The former is associated with the disease Friedreich ataxia and the latter plays a key role in iron homeostasis in mitochondria. CyaY has been overexpressed in soluble form in E. coli. The recombinant protein with a His(6) tag at its C-terminus has been crystallized at 296 K using polyethylene glycol (PEG) 4000 as a precipitant. Native diffraction data have been collected to 1.8 A using Cu Kalpha X-rays. The crystals belong to the trigonal space group P3(1)21 (or P3(2)21), with unit-cell parameters a = b = 44.66, c = 99.87 A, alpha = beta = 90.0, gamma = 120.0 degrees. The asymmetric unit contains one molecule of recombinant CyaY, with a corresponding V(m) of 2.13 A(3) Da(-1) and solvent content of 42.3%.

Clinical improvement and immunohistochemical findings in severe atopic dermatitis treated with interferon gamma

BACKGROUND

Several clinical studies have focused on the therapeutic effects of interferon gamma (IFN-gamma) in patients with severe atopic dermatitis (AD), although the dosage of recombinant IFN-gamma (rIFN-gamma), therapeutic schedule, and the degree of clinical improvement were different among studies. Although the exact mechanism of action of IFN-gamma therapy in AD is not clear, the beneficial effects of IFN-gamma have been attributed mainly to an immunomodulating effect on the expression of certain immunologic markers.

OBJECTIVE

Our purpose was to study the therapeutic effect of two different dosages of rIFN-gamma on AD and to investigate the change of lesional expression of infiltrating inflammatory cell markers associated with rIFN-gamma therapeutic efficacy.

METHODS

Fifty-one patients with severe recalcitrant AD were treated with rIFN-gamma. Twenty patients were treated with 0.5 x 10(6) IU/m(2) of rIFN-gamma (low-dose [LD] group); 21 patients received 1.5 x 10(6) IU/m(2) of rIFN-gamma (high-dose [HD] group); and 10 patients received placebo. The patients were injected subcutaneously 3 times a week for 12 weeks. Immunohistochemical study was performed in 20 patients of the HD group in the initial visit and after completion of rIFN-gamma therapy with a panel of 14 monoclonal antibodies as markers of inflammatory cells and cytokines.

RESULTS

The disease severity of the 2 groups treated with rIFN-gamma was reduced significantly at the end of treatment compared with that of the placebo group (P<.05). More rapid clinical improvement and more effective treatment outcome were seen in the HD group than in the LD group for the initial 6-week treatment period; however, the clinical improvement in both of the treated groups was stable and maintained after week 8 of treatment. Immunohistochemical findings showed statistically significant reduction in the lesional expression of CD25 and EG2 cells that infiltrated into skin after rIFN-gamma therapy.

CONCLUSION

This study demonstrated that rIFN-gamma therapy for AD is safe and effective. In the early phase of therapy, a higher dosage of rIFN-gamma is more effective; and for the maintenance of clinical improvement, a lower dosage of rIFN-gamma is recommended when high cost and effectiveness of rIFN-gamma are considered. The therapeutic efficacy of rIFN-gamma in AD might be in part related to the decreased number of CD25(+) and EG2(+) inflammatory cells infiltrated into skin.

Crystallization and preliminary X-ray crystallographic analysis of human nucleoside diphosphate kinase A

Human nucleoside diphosphate kinase A catalyzes phosphoryl transfer and acts as a suppressor of metastasis. It has been crystallized using 2-methyl-2,4-pentanediol as a precipitant at 288 K. The crystal is monoclinic, belonging to the space group P2(1), with unit-cell parameters a = 74.21, b = 78.11, c = 82.29 A, beta = 101. 33 degrees. The asymmetric unit contains a homohexamer, with a corresponding crystal volume per protein mass (V(m)) of 2.27 A(3) Da(-1) and a solvent content of 46%. Native X-ray data to 2.15 A resolution have been collected using synchrotron X-rays.

Crystal structure of NAD(+)-dependent DNA ligase: modular architecture and functional implications

DNA ligases catalyze the crucial step of joining the breaks in duplex DNA during DNA replication, repair and recombination, utilizing either ATP or NAD(+) as a cofactor. Despite the difference in cofactor specificity and limited overall sequence similarity, the two classes of DNA ligase share basically the same catalytic mechanism. In this study, the crystal structure of an NAD(+)-dependent DNA ligase from Thermus filiformis, a 667 residue multidomain protein, has been determined by the multiwavelength anomalous diffraction (MAD) method. It reveals highly modular architecture and a unique circular arrangement of its four distinct domains. It also provides clues for protein flexibility and DNA-binding sites. A model for the multidomain ligase action involving large conformational changes is proposed.

Crystal structure of a 16 kDa double-headed Bowman-Birk trypsin inhibitor from barley seeds at 1.9 A resolution

The Bowman-Birk trypsin inhibitor from barley seeds (BBBI) consists of 125 amino acid residues with two inhibitory loops. Its crystal structure in the free state has been determined by the multiwavelength anomalous diffraction (MAD) method and has been refined to a crystallographic R-value of 19.1 % for 8.0-1.9 A data. This is the first report on the structure of a 16 kDa double-headed Bowman-Birk inhibitor (BBI) from monocotyledonous plants and provides the highest resolution picture of a BBI to date. The BBBI structure consists of 11 beta-strands and the loops connecting these beta-strands but it lacks alpha-helices. BBBI folds into two compact domains of similar tertiary structure. Each domain shares the same overall fold with 8 kDa dicotyledonous BBIs. The five disulfide bridges in each domain are a subset of the seven disulfide bridges in 8 kDa dicotyledonous BBIs. Two buried water molecules form hydrogen bonds to backbone atoms in the core of each domain. One interesting feature of this two-domain inhibitor structure is that the two P1 residues (Arg17 and Arg76) are approximately 40 A apart, allowing the two reactive-site loops to bind to and to inhibit two trypsin molecules simultaneously and independently. The conformations of the reactive-site loops of BBBI are highly similar to those of other substrate-like inhibitors. This structure provides the framework for modeling of the 1:2 complex between BBBI and trypsin.

Insights into eukaryotic multistep phosphorelay signal transduction revealed by the crystal structure of Ypd1p from Saccharomyces cerevisiae

"Two-component" phosphorelay signal transduction systems constitute a potential target for antibacterial and antifungal agents, since they are found exclusively in prokaryotes and lower eukaryotes (yeast, fungi, slime mold, and plants) but not in mammalian organisms. Saccharomyces cerevisiae Ypd1p, a key intermediate in the osmosensing multistep phosphorelay signal transduction, catalyzes the phosphoryl group transfer between response regulators. Its 1.8 A structure, representing the first example of a eukaryotic phosphorelay protein, contains a four-helix bundle as in the HPt domain of Escherichia coli ArcB sensor kinase. However, Ypd1p has a 44-residue insertion between the last two helices of the helix bundle. The side-chain of His64, the site of phosphorylation, protrudes into the solvent. The structural resemblance between Ypd1p and ArcB HPt domain suggests that both prokaryotes and lower eukaryotes utilize the same basic protein fold for phosphorelay signal transduction. This study sheds light on the best characterized eukaryotic phosphorelay system.

Competitive Adsorption of Cu(II)-EDTA and Cd(II)-EDTA onto TiO2

Cu(II), EDTA, Cu(II)-EDTA, Cd(II)-EDTA, and Cu(II)/Cd(II) and Cu(II)-EDTA/Cd(II)-EDTA competitive adsorption onto TiO2 has been studied with variation of pH and concentration. For Cu(II) and EDTA, typical cationic and anionic types of adsorption are noted, respectively. Ligand-type adsorption is found for Cu(II)-EDTA and Cd(II)-EDTA under both single and competitive conditions. Surface complexation modeling considered inner-sphere complexation and the diffuse layer model employing MINTEQA2; surface complexes used include Ti-(OH2)O-Cu+, Ti-(OH)EDTAH-22, Ti-(OH)EDTA-Cu-2, and Ti-(OH)EDTA-Cd-2. Experimental and model predictions suggest no competitive adsorption between Cu(II) and Cd(II) at 5 x 10(-5) M. On the other hand, adsorption data and model predictions indicate that Cd(II)-EDTA adsorption is favored over that of Cu(II)-EDTA with some competition for adsorption sites. Cd(II)-EDTA adsorption was only slightly affected by the presence of Cu(II)-EDTA; however, Cu(II)-EDTA adsorption was strongly influenced by the presence of Cd(II)-EDTA, especially as the molar ratio of Cd(II)-EDTA/Cu(II)-EDTA increased. A modified surface complexation constant for Cd(II)-EDTA is required to explain the competitive data, suggesting surface site heterogeneity. Copyright 1999 Academic Press.

Effects of glutathione depletion using buthionine sulphoximine on the cytotoxicity in mammalian cells and human tumor cells in vitro

An inhibitor of glutathione biosynthesis, buthionine sulphoximine (BSO), was used to deplete the endogenous thiols in mammalian cells in vitro. In this study, the cytotoxicity of BSO and BSO combined with the hypoxic cell radiosensitizer misonidazole (MISO) was investigated. Both aerobic and hypoxic cytotoxicity of MISO was found to be increased. The concentration of BSO required to reduce the colony forming ability to 50% (Cc) for the chronic cytotoxicity on V79 cells was 0.03 mmol/L under aerobic condition, while the Cc for the acute cytotoxicity on V79 cells under hypoxic and aerobic conditions was 0.4 and 0.5 mmol/L. The growth inhibition rate of human tumor cells K562 and SGC-7901 by BSO was 6.89-26.06% and 12.01-55.69%, respectively. Enhanced cytotoxicity activity was observed when BSO was used in combination with cis-dichlorodiamino Pt(II) or 5-fluorouracil.

Influence of medicinal herbs decocted with different utensils on colony formation of gastric carcinoma cells

In order to elucidate the different results obtained in cancer patients with similar condition and symptoms treated by the same medicinal herbs, an investigation of the utensils used for making decoctions was carried out. It was found that the decoction made by means of glassware, enamel and earthenware pots had the best effect of inhibiting the colony formation of human gastric carcinoma cells, the next were the decoctions made by means of unrefined iron pots, stainless steel pots and copper pots, and the worst was that made with aluminium pots. It was also found that there was no difference between the water contained in those utensils and normal saline in the influence on the colony formation of human gastric carcinoma cells. Therefore, it is believed that the difference in effect of the decoctions made by means of different kinds of utensils is not due to the trace dissolution of the utensil materials, but is most likely due to the occurrence of some chemical reactions while making the decoction. That the decoctions made by means of different utensils had different peak values in the absorption spectrum also supports this proposition.

Human dihydrofolate reductase gene organization. Extensive conservation of the G + C-rich 5' non-coding sequence and strong intron size divergence from homologous mammalian genes

The complete human dihydrofolate reductase (DHFR) gene has been cloned from four recombinant lambda libraries constructed with the DNA from a methotrexate-resistant human cell line with amplified DHFR genes. The detailed organization of the gene has been determined by restriction mapping of the cloned fragments and DNA sequencing of all the protein coding regions and adjacent intron segments, and shown to correspond to that of the native human DHFR gene. The gene spans a length of approximately 29 X 10(3) bases from the ATG initiator codon to the end of the 3' untranslated region, and contains five introns that interrupt the protein coding sequence. The number and positions of introns are identical to those found in the mouse gene. By contrast, the size of the homologous introns (with the exception of the first one) varies greatly, up to several fold, in the genes from man, mouse and Chinese hamster; the intron sequences also exhibit a great divergence, except in the junction regions. A striking sequence homology, extending over several hundred nucleotides, exists between the human and mouse gene 5' non-coding regions. These regions are characterized by an unusually high G + C content, 72% and 66% in the human and mouse genes, respectively, which is maintained in the first coding segment and first intron, and is in sharp contrast to the relatively low G + C content (approximately 40%) of the remainder of the gene.

A human dihydrofolate reductase pseudogene and its relationship to the multiple forms of specific messenger RNA

The presence of dihydrofolate reductase (DHFRase)-specific sequences that, in contrast to the normal DHFRase gene, are not amplified in a methotrexate-resistant cell line, has been detected in the DNA from human sperm and from several human cell lines. DNA fragments containing some of these sequences have been isolated from a cosmid library of human sperm DNA. One of these fragments contains a DHFRase pseudogene (psi HD1) that completely lacks introns, has 92% sequence homology to the corresponding region of normal DHFRase complementary DNA, but exhibits several alterations that make it nonfunctional. The sequence analysis of the inserts of four different plasmids containing the reading frame and varying lengths of the 3' non-coding regions of human DHFRase-specific cDNAs has revealed that the 3' non-coding segments all are colinear in their corresponding portions. Furthermore, the data indicate that the cDNA of one of the plasmids is probably derived from the smallest of the three main human DHFRase messenger RNAs, the 0.8 X 10(3) base (0.8 kb) mRNA, the cDNA of two others, from the 1.0 kb mRNA, and the cDNA of the fourth, from a longer mRNA. These results are consistent with the idea that the multiple forms of DHFRase mRNA in human cells derive from the same gene by different transcription or RNA-processing events. Moreover, the sequence comparison between the psi HD1 and the different DHFRase cDNAs clearly indicates that, if an mRNA intermediate has participated in the formation of this pseudogene, a form of mRNA larger than the 1.0 kb mRNA, probably the 3.8 kb mRNA, must have been involved.

Purification and characterization of adenylate cyclase from Escherichia coli K12

Adenylate cyclase of Escherichia coli K12 has been purified 17,000-fold to near homogeneity from a 5-fold overproducing strain. One major band of Mr = 92,000 and several minor bands are seen on sodium dodecyl sulfate-polyacrylamide electrophoresis of the purest fractions. Identification of the enzyme with the 92,000-Da protein is based on the correlation of this band with activity when highly purified enzyme is eluted from ADP-sepharose columns. The native enzyme has a molecular weight of 95,000 determined by gel filtration, showing that the enzyme is active as a monomer. The purest enzyme has a specific activity of 700 nmol min-1 mg-1, indicating a turnover number of about 100 min-1. Our data indicate that there are only about 15 molecules of the enzyme in wild type cells of E. coli. In crude extracts, over 80% of the activity is soluble after centrifugation at 100,000 x g, indicating the enzyme is soluble or, at most, loosely membrane bound. The enzyme is only moderately stable in crude extracts and becomes more unstable as purification proceeds. Activity is stabilized by ATP, or at -20 degrees C as an ammonium sulfate precipitate or in 50% glycerol. The enzyme has an absolute requirement for divalent cations. Maximum activity with Mg2+ is reached at 30 mM. Mn2+ is a good substitute; Co2+ activates well at low concentrations but becomes inhibitory at high concentrations; and Ca2+ is a potent inhibitor in the presence of Mg2+. The isoelectric point of the enzyme is 6.1, and its pH optimum is 8.5. The enzyme is inhibited by its substrate, with a Km of about 1 mM and a Ki of about 1.5 mM, and is noncompetitively inhibited by PPi, ADP, GTP, and a number of other compounds. The data suggest that dissociation of PPi from the first enzyme-product complex is the rate-limiting step in the reaction. Activation of the enzyme, inferred to occur in vivo, could be produced by a postulated regulatory effector which speeds release of PPi from the enzyme-product complex.

Catabolite and transient repression in Escherichia coli do not require enzyme I of the phosphotransferase system

Transient and catabolite repression with changes in intracellular concentrations of cyclic adenosine 3',5-monophosphate is produced by glycerol and by glucose-6-phosphate in a strain with a partial deletion of the structural gene for enzyme I of the phosphoenolpyruvate:sugar phosphotransferase system.