Target size analysis by radiation inactivation of carnitine palmitoyltransferase activity and malonyl-CoA binding in outer membranes from rat liver mitochondria.

The functional molecular sizes of the protein(s) mediating the carnitine palmitoyltransferase I (CPT I) activity and the [14C]malonyl-CoA binding in purified outer-membrane preparations from rat liver mitochondria were determined by radiation-inactivation analysis. In all preparations tested the dose-dependent decay in [14C]malonyl-CoA binding was less steep than that for CPT I activity, suggesting that the protein involved in malonyl-CoA binding may be smaller than that catalysing the CPT I activity. The respective sizes computed from simultaneous analysis for molecular-size standards exposed under identical conditions were 60,000 and 83,000 DA for malonyl-CoA binding and CPT I activity respectively. In irradiated membranes the sensitivity of CPT activity to malonyl-CoA inhibition was increased, as judged by malonyl-CoA inhibition curves for the activity in control and in irradiated membranes that had received 20 Mrad radiation and in which CPT activity had decayed by 60%. Possible correlations between these data and other recent observations on the CPT system are discussed.     

Isolation and characterization of porcine somatotropin containing a succinimide residue in place of aspartate129.

Aspartate129 in porcine somatotropin was converted into a cyclic imide residue (succinimide) under acidic solution conditions. Reversed-phase high performance liquid chromatography was utilized to isolate and quantitate this altered species, which accounted for approximately 30% of the total protein. The molecular mass of this modified species was determined by electrospray mass spectrometry to be 18 Da less than normal porcine somatotropin, indicative of a loss of 1 H2O molecule. Tryptic peptide mapping demonstrated that the peptide composed of residues 126-133 was altered in this modified protein. Amino acid analysis, amino acid sequencing, mass spectrometry, and capillary zone electrophoresis were used to demonstrate that aspartate129 in this peptide had been converted into a succinimide residue. Further confirmation that this peptide contained a succinimide was obtained by hydrolyzing the modified peptide at pH 9.0, which yielded both the aspartate and isoaspartate peptides.     

Comparative effects of trichothecene mycotoxins on bovine platelet function: Acetyl T-2 toxin,a more potent inhibitor than T-2 toxin

The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10^?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.     

A survey on Green communications using Adaptive Link Rate

The Information and Communication Technology sector is considered to be a major consumer of energy and has become an active participant in Green House Gas emissions. Lots of efforts have been devoted to make network infrastructure and network protocols power-aware and green. Among these efforts, Adaptive Link Rate (ALR) is one of the most widely discussed approaches. This survey highlights the most recent ALR approaches with a brief taxonomy and the state of the art.     

吐鲁番市胃食管反流病发生相关危险因素分析（附280例报道）

目的：探讨280例胃食管反流病（GERD）的分布特点及危险因素。方法：对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果：不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者（z=-2．939,P=0．003,）;汉族和维族患者占反流性食管炎和Barrett食管比例分别为42．4％、81_3％及56．5％、18．8％,其中汉族患者Barrett食管比例较高（X2=14．358,P=0．000）;肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高（P〈0．001）。结论：GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。     

A mutation in COL9A1 causes multiple epiphyseal dysplasia: further evidence for locus heterogeneity

Multiple epiphyseal dysplasia (MED) is an autosomal dominantly inherited chondrodysplasia. It is clinically highly heterogeneous, partially because of its complex genetic background. Mutations in four genes, COL9A2, COL9A3, COMP, and MATR3, all coding for cartilage extracellular matrix components (i.e., the alpha2 and alpha 3 chains of collagen IX, cartilage oligomeric matrix protein, and matrilin-3), have been identified in this disease so far, but no mutations have yet been reported in the third collagen IX gene, COL9A1, which codes for the alpha1(IX) chain. MED with apparently recessive inheritance has been reported in some families. A homozygous R279W mutation was recently found in the diastrophic dysplasia sulfate transporter gene, DTDST, in a patient with MED who had a club foot and double-layered patella. The series consisted of 41 probands with MED, 16 of whom were familial and on 4 of whom linkage analyses were performed. Recombination was observed between COL9A1, COL9A2, COL9A3, and COMP and the MED phenotype in two of the families, and between COL9A2, COL9A3, and COMP and the phenotype in the other two families. Screening of COL9A1 for mutations in the two probands from the families in which this gene was not involved in the recombinations failed to identify any disease-causing mutations. The remaining 37 probands were screened for mutations in all three collagen IX genes and in the COMP gene. The probands with talipes deformities or multipartite patella were also screened for the R279W mutation in DTDST. The analysis resulted in identification of three mutations in COMP and one in COL9A1, but none in the other two collagen IX genes. Two of the probands with a multipartite patella had the homozygous DTDST mutation. The results show that mutations in COL9A1 can cause MED, but they also suggest that mutations in COL9A1, COL9A2, COL9A3, COMP, and DTDST are not the major causes of MED and that there exists at least one additional locus.     

Cuticular wax profiles of leaves of some traditionally used African Bignoniaceae

Bignoniaceae, Newbouldia laevis, Markhamia acuminata, Spathodea campanulata and Kigelia africana were analysed by GC-MS. The principal constituents were represented by a homologous series of n-alkanes (C23-C33), n-alcohols (C18-C30) and related carboxylic acids (C16-C36). For N. laevis and M. acuminata, ursolic and oleanolic acid were the most abundant wax components (52 and 60%, respectively), followed by the C29, the C31 and the C33 n-alkanes. The predominant components of S. campanulata were n-alcohols (35%), with octacosanol and triacontanol as the most abundant ones, while K. africana is distinguished from these three members by the conspicuous absence of triterpenoic acids and the predominance of n-alkanes (70%) with hentriacontane and tritriacontane as the main representatives. Other notable constituents were sterols, albeit present in trace amounts. The wax profiles are discussed in terms of taxonomic characters.     

Isolation of Rho GTPase effector pathways during axon development

The Rho GTPases Rac1 and Cdc42 have been implicated in the regulation of axon outgrowth and guidance. However, the downstream effector pathways through which these GTPases exert their effects on axon development are not well characterized. Here, we report that axon outgrowth defects within specific subsets of motoneurons expressing constitutively active Drosophila Rac1 largely persist even with the addition of an effector-loop mutation to Rac1 that disrupts its ability to bind to p21-activated kinase (Pak) and other Cdc42/Rac1 interactive-binding (CRIB)-motif effector proteins. While hyperactivation of Pak itself does not lead to axon outgrowth defects as when Rac1 is constitutively activated, live analysis reveals that it can alter filopodial activity within specific subsets of neurons similar to constitutive activation of Cdc42. Moreover, we show that the axon guidance defects induced by constitutive activation of Cdc42 persist even in the absence of Pak activity. Our results suggest that (1) Rac1 controls axon outgrowth through downstream effector pathways distinct from Pak, (2) Cdc42 controls axon guidance through both Pak and other CRIB effectors, and (3) Pak's primary contribution to in vivo axon development is to regulate filopodial dynamics that influence growth cone guidance.     

Successful immunotherapy with matrix metalloproteinase-derived peptides in adjuvant arthritis depends on the timing of peptide administration

We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development of such therapies.