HLA BW54 and B5 in Japanese diabetics with juvenile-onset and insulin-dependency (with special reference to the family history)

Summary The frequency of HLA BW54 and B5 in Japanese patients with JOD is increased and decreased, respectively. In JOD patients without a family history of MOD, the frequency of BW54 is significantly increased, whereas in JOD patients with a positive family history the frequency was not increased in a statistically significant manner.     

Interaction of BW755C,a potent inhibitor of lipoxygenase and cyclo-oxygenase,with mitochondrial cytochrome oxidase

Summary The interaction between BW755C (3-amino-1-[m-(trifluoromethyl)phenyl]-2-pyrazoline), a potent inhibitor of both lipoxygenase and cyclo-oxygenase, and respiratory chain in mitochondria and electron transport particles (ETP) from rat livers was examined. BW755C accelerated the oxygen uptake by mitochondria without the addition of substrate for the respiratory chain. Spectrophotometric study revealed that BW755C was quickly oxidized by cytochrome oxidase in mitochondria to a compound possessing an absorption maximum at 524 nm. p-Phenylenediamine (p-diaminobenzene, PPDA), which, like BW755C, serves as an electron donor to cytoschrome oxidase, was shown to inhibit the generation of active oxygen in macrophages; the inhibition was stronger than that of BW755C. These results strongly suggest that the oxidative conversion of BW755C by mitochondrial cytochrome oxidase is associated with its potentially inhibitory action on the active oxygen-generating system in phagocytes.The authors are indebted to Dr M. Hori, Gifu College of Pharmacy and to Dr Y. Orii, Kyoto University for their kind supplies of BW755C and pure cytochrome oxidase, respectively.     

Interaction of BW755C, a potent inhibitor of lipoxygenase and cyclo-oxygenase, with mitochondrial cytochrome oxidase

The interaction between BW755C (3-amino-1-[m-(trifluoromethyl)phenyl]-2-pyrazoline), a potent inhibitor of both lipoxygenase and cyclo-oxygenase, and respiratory chain in mitochondria and electron transport particles (ETP) from rat livers was examined. BW755C accelerated the oxygen uptake by mitochondria without the addition of substrate for the respiratory chain. Spectrophotometric study revealed that BW755C was quickly oxidized by cytochrome oxidase in mitochondria to a compound possessing an absorption maximum at 524 nm. p-Phenylenediamine (p-diaminobenzene, PPDA), which, like BW755C, serves as an electron donor to cytochrome oxidase, was shown to inhibit the generation of active oxygen in macrophages; the inhibition was stronger than that of BW755C. These results strongly suggest that the oxidative conversion of BW755C by mitochondrial cytochrome oxidase is associated with its potentially inhibitory action on the active oxygen-generating system in phagocytes.     

Resting energy expenditure in patients with cirrhosis of the liver measured by indirect calorimetry,anthropometry and bioelectrical impedance analysis

Energy expenditure was investigated in 15 patients with liver cirrhosis and 20 healthy controls by three methods: indirect calorimetry, anthropometry using the Harris-Benedict equation and bioelectrical impedance analysis. The energy expenditure was expressed in kcal/day, kcal/kg BW/day (BW — body weight), kcal/kg LBM/day (LBM — lean body mass, derived by bioelectrical impedance analysis) or in kcal/m²/day. We did not find statistical differences between values of resting energy expenditure obtained in patients with cirrhosis of the liver and healthy controls whichever method we used. We also did not find statistical differences between values obtained by indirect calorimetry, anthropometry and bioelectrical impedance analysis. There was a significant correlation between indirect calorimetry and anthropometry in both groups. We found significant correlations between indirect calorimetry and anthropometry, and between indirect calorimetry and bioelectrical impedance analysis, in the control group only. We can conclude that (1) resting energy expenditure of patients with cirrhosis of the liver is not changed when compared with healthy controls, and (2) bioelectrical impedance is a useful method to calculate body composition from which energy expenditure is derived; however, it gives an appropriate result only in healthy people, and only approximate values in patients with cirrhosis.     

Erythrocyte magnesium and HLA groups]

Red blood cell Magnesium levels were determined in 351 unrelated male subjects with known HLA groups. Significantly lower values are observed among subjects carrying BW 35 allele. Furthermore, significant variations are also noted according to the constitution of HLA-B groups with respect to BW 4 and BW 6 public specificities. This observation brings to light other variations among the subjects carrying B 8 allele.     

Genetic susceptibility to hypertensive renal disease

Hypertensive renal disease occurs at increased frequency among the relatives of patients with this disease compared to individuals who lack a family history of disease. This suggests a heritable risk in which genetic variation may play a role. These observations have motivated a search for genetic variation contributing to this risk in both experimental animal models and in human populations. Studies of animal models indicate the capacity of natural genetic variants to contribute to disease risk and have produced a few insights into the disease mechanism. In its current phase, human population genetic studies have sought to associate genetic variation with disease in large populations by testing genotypes at a large number of common genetic variations in the genome, expecting that common genetic variants contributing to renal disease risk will be identified. These genome-wide association studies (GWAS) have been productive and are a clear technical success; they have also identified narrowly defined loci and genes containing variation contributing to disease risk. Further extension and refinement of these GWAS are likely to extend this success. However, it is also clear that few additional variants with substantial effects accounting for the greatest part of heritability will be uncovered by GWAS. This raises an interesting biological question regarding where the remaining unaccounted heritable risk may be located. At present, much consideration is being given to this question and to the challenge of testing hypotheses that lead from the various alternative mechanisms under consideration. One result of the progress of GWAS is likely to be a renewed interest in mechanisms by which related individuals can share and transmit traits independently of Mendelian inheritance. This paper reviews the current progress in this area and considers other mechanisms by which familial aggregation of risk for renal disease may arise.     

Low-density lipoprotein receptor structure and folding

The endoplasmic reticulum (ER) is a major cellular 'production factory' for many membrane and soluble proteins. A quality control system ensures that only correctly folded and assembled proteins leave the compartment. The low-density lipoprotein receptor (LDLR) is the prototype of a large family of structurally homologous cell surface receptors, which fold in the ER and function as endocytic and signaling receptors in a wide variety of cellular processes. Patients with familial hypercholesterolemia carry single or multiple mutations in their LDLR, which leads to malfunction of the protein, in most patients through misfolding of the receptor. As a result, clearance of cholesterol-rich LDL particles from the circulation decreases, and the elevated blood cholesterol levels cause early onset of atherosclerosis and an increased risk of cardiac disease in these patients. In this review, we will elaborate on the structural aspects of the LDLR and its folding pathway and compare it to other LDLR family members.     

The Rh protein family: gene evolution, membrane biology, and disease association

The Rh (Rhesus) genes encode a family of conserved proteins that share a structural fold of 12 transmembrane helices with members of the major facilitator superfamily. Interest in this family has arisen from the discovery of Rh factor’s involvement in hemolytic disease in the fetus and newborn, and of its homologs widely expressed in epithelial tissues. The Rh factor and Rh-associated glycoprotein (RhAG), with epithelial cousins RhBG and RhCG, form four subgroups conferring upon vertebrates a genealogical commonality. The past decade has heralded significant advances in understanding the phylogenetics, allelic diversity, crystal structure, and biological function of Rh proteins. This review describes recent progress on this family and the molecular insights gleaned from its gene evolution, membrane biology, and disease association. The focus is on its long evolutionary history and surprising structural conservation from prokaryotes to humans, pointing to the importance of its functional role, related to but distinct from ammonium transport proteins.     

A negative association of HLA-BW52 with Graves' disease and insulin-dependent diabetes mellitus with juvenile onset among Japanese population

The present study demonstrated that a decreased frequency of HLA-BW52 was a common characteristic shared by the patients with Graves' disease and insulin-dependent diabetes mellitus with juvenile onset among Japanese.     

A negative association of HLA-BW52 with Graves' disease and insulin-dependent diabetes mellitus with juvenile onset among Japanese population

Summary The present study demonstrated that a decreased frequency of HLA-BW52 was a common characteristic shared by the patients with Graves' disease and insulin-dependent diabetes mellitus with juvenile onset among Japanese.     

A glucagon-secretin-like peptide stimulates the intrinsic nervous plexus of guinea pig gallbladder

The role of vasoactive intestinal peptide (VIP), as a possible neurotransmitter of the intrinsic nerve plexus in the guinea pig gallbladder, was investigated by monitoring spontaneous contractile activity. VIP receptor antagonist (4 Cl-D-Phe6, Leu 17)-VIP did not produce any effect on muscular tone and spontaneous activity, whereas (N-Ac-Tyr1, D-Phe2)-GRF-(1-29)-NH2, (14-GRF analog), which is known to stimulate digestive enzyme secretion by interacting with the VIP-preferring receptors, greatly increased the amplitude and frequency of waves as well as the muscular tone. Since VIP receptor antagonist acts selectively as a competitive antagonist for the action of VIP, we conclude that the gallbladder inhibitory intrinsic plexus neurotransmitter is not VIP, but a member of the glucagon-secretin family of peptides.     

Cathepsin A/protective protein: an unusual lysosomal multifunctional protein

Cathepsin A/protective protein [3.4.16.5], carboxypeptidase A, is a lysosomal serine protease with structural homology to yeast (Saccharomyces cerevisiae) carboxypeptidase Y. Cathepsin A is a member of the alpha/beta hydrolase fold family and has been suggested to share a common ancestral relationship with other alpha/beta hydrolase fold enzymes, such as cholinesterases. Several lines of evidence indicate that cathepsin A is a multicatalytic enzyme with deamidase and esterase in addition to carboxypeptidase activities. Cathepsin A was recently identified in human platelets as deamidase. In vitro, it hydrolyzes a variety of bioactive peptide hormones including tachykinins, suggesting that extralysosomal cathepsin A plays a role in regulation of bioactive peptide functions. Recent reports emphasize the lysosomal protective function of cathepsin A rather than its protease function. The protective function of cathepsin A is distinct from its catalytic function. Human lysosomal beta-galactosidase and neuraminidase exist as a high molecular weight enzyme complex, in which there is a 54-kDa glycoprotein termed 'lysosomal protective protein'. Based on cell culture studies, protective protein was found to protect both beta-galactosidase and neuraminidase from intralysosomal proteolysis by forming a multienzyme complex and was shown to be deficient in patients with galactosialidosis, a combined deficiency of beta-galactosidase and neuraminidase. Molecular cloning and gene expression studies have disclosed that protective protein is cathepsin A. The cathepsin A precursor has the potential to restore both beta-galactosidase and neuraminidase activities in fibroblasts from patients with galactosialidosis. Cathepsin A knockout mice showed a phenotype similar to human galactosialidosis and the deficient phenotype found in the mutant mice was corrected by transplanting erythroid precursor cells overexpressing cathepsin A. Collectively, these findings demonstrate the significance of cathepsin A as a key molecule in the onset of galactosialidosis and also highlight the therapeutic potential of the cathepsin A precursor for patients with galactosialidosis.     

Opposite roles of protein kinase C isoforms in proliferation, differentiation, apoptosis, and tumorigenicity of human HaCaT keratinocytes

We have previously shown that the protein kinase C (PKC) system plays a pivotal role in regulation of proliferation and differentiation of the human keratinocyte line HaCaT which is often used to assess processes of immortalization, transformation, and tumorigenesis in human skin. In this paper, using pharmacological and molecular biology approaches, we investigated the isoform-specific roles of certain PKC isoenzymes (conventional cPKC and ; novel nPKC and ) in the regulation of various keratinocyte functions. cPKC and nPKC stimulated cellular differentiation and increased susceptibility of cells to actions of inducers of apoptosis, and they markedly inhibited cellular proliferation and tumor growth in immunodeficient mice. In marked contrast, cPKC and nPKC increased both in vitro and in vivo growth of cells and inhibited differentiation and apoptosis. Our data present clear evidence for the specific, antagonistic roles of certain cPKC and nPKC isoforms in regulating the above processes in human HaCaT keratinocytes.Received 13 January 2004; received after revision 18 February 2004; accepted 25 February 2004     

时频分布中交叉项抑制的研究进展

从整个时频分析发展的历史来看，其发展过程是以克服Wigner-Ville分布（WVD）的缺陷为动力的。本文以抑制Wigner-Ville分布中的交叉项为线索，在简要介绍时频分析中已有的一些方法的基础上，综述了近年来在抑制交叉项干扰方面的研究进展，并对现存的有关问题进行了探讨。     

A glucagon-secretin-like peptide stimulates the intrinsic nervous plexus of guinea pig gallbladder

Summary The role of vasoactive intestinal peptide (VIP), as a possible neurotransmitter of the intrinsic nerve plexus in the guinea pig gallbladder, was investigated by monitoring spontaneous contractile activity. VIP receptor antagonist (4 Cl-D-Phe⁶, Leu¹⁷)-VIP did not produce any effect on muscular tone and spontaneous activity, whereas (N-Ac-Tyr¹, D-Phe²)-GRF-(1-29)-NH₂, (14-GRF analog), which is known to stimulate digestive enzyme secretion by interacting with the VIP-preferring receptors, greatly increased the amplitude and frequency of waves as well as the muscular tone. Since VIP receptor antagonist acts selectively as a competitive antagonist for the action of VIP, we conclude that the gallbladder inhibitory intrinsic plexus neurotransmitter is not VIP, but a member of the glucagon-secretin family of peptides.     

IFT54 regulates IFT20 stability but is not essential for tubulin transport during ciliogenesis

Intraflagellar transport (IFT) is required for ciliogenesis by ferrying ciliary components using IFT complexes as cargo adaptors. IFT54 is a component of the IFT-B complex and is also associated with cytoplasmic microtubules (MTs). Loss of IFT54 impairs cilia assembly as well as cytoplasmic MT dynamics. The N-terminal calponin homology (CH) domain of IFT54 interacts with tubulins/MTs and has been proposed to transport tubulin during ciliogenesis, whereas the C-terminal coiled-coil (CC) domain binds IFT20. However, the precise function of these domains in vivo is not well understood. We showed that in Chlamydomonas, loss of IFT54 completely blocks ciliogenesis but does not affect spindle formation and proper cell cycle progression, even though IFT54 interacts with mitotic MTs. Interestingly, IFT54 lacking the CH domain allows proper flagellar assembly. The CH domain is required for the association of IFT54 with the axoneme but not with mitotic MTs, and also regulates the flagellar import of IFT54 but not IFT81 and IFT46. The C-terminal CC domain is essential for IFT54 to bind IFT20, and for its recruitment to the basal body and incorporation into IFT complexes. Complete loss of IFT54 or the CC domain destabilizes IFT20. ift54 mutant cells expressing the CC domain alone rescue the stability of IFT20 and form stunted flagella with accumulation of both IFT-A component IFT43 and IFT-B component IFT46, indicating that IFT54 also functions in IFT turn-around at the flagellar tip.     

An MD2-derived peptide promotes LPS aggregation,facilitates its internalization in THP-1 cells,and inhibits LPS-induced pro-inflammatory responses

MD2, a 160-residue accessory glycoprotein, is responsible for the recognition and binding of Gram-negative bacterial membrane component, lipopolysaccharide (LPS). Internalization of pathogen inside the mononuclear phagocytes has also been attributed to MD2 which leads to the clearance of pathogens from the host. However, not much is known about the segments in MD2 that are responsible for LPS interaction or internalization of pathogen inside the defense cells. A 16-residue stretch (MD54) from MD2 protein has been identified that possesses a short heptad repeat sequence and four cationic residues enabling it to participate in both hydrophobic and electrostatic interactions with LPS. An MD54 analog of the same size was also designed in which a leucine residue at a heptadic position was replaced with an alanine residue. MD54 but not its analog, MMD54 induced aggregation of LPS and aided in its internalization within THP-1 monocytes. Furthermore, MD54 inhibited LPS-induced nuclear translocation of NF-κB in PMA-treated THP-1 and TLR4/MD2/CD14-transfected HEK-293T cells and the production of pro-inflammatory cytokines. In addition, in in vivo experiments, MD54 showed marked protection and survival of mice against LPS-induced inflammation and death. Overall, we have identified a short peptide with heptad repeat sequence from MD2 that can cause aggregation of LPS and abet in its internalization within THP-1 cells, resulting in attenuation of LPS-induced pro-inflammatory responses in vitro and in vivo.     

中国汉族人群中Vav2基因和Vav3基因多态性与原发性闭角型青光眼之间关系的研究

目的本实验的目的是研究沌以和Vav3基因多态性与中国汉族人群中原发性闭角型青光眼（Prim aryangle-closure glaucoma,PACG）的遗传性是否有联系。方法211名原发性闭角型青光眼患者和206名性别和种族匹配的健康对照者纳入到本病例对照研究中。2个单核苷酸多态（the single nucleotide polymorphisms,SNPs）rs2156323（Vav2）和rs2801219（vav3）的基因分型用聚合酶链反应的限制性片段长度多态性分析（polymerase chain reaction restriction fragment length polymorphism,PCR—RFLP）。这两个基因位点的多态性与PACG遗传性之间的关系用卡方检验来评价。结果rs2156323（Vav2）和rs2801219（Vav3）的基因频率在所有参与者中均没有偏离哈迪一温伯格平衡（Hardy-Weinberg Equilibrium,HWE,P〉0．05）。该两个位点的等位基因频率和基因型频率的分布在PACG患者和正常对照者之间均没有差异。结论本研究的结果显示rs2156323和rs2801219可能不是中国汉族PACG的易感基因位点,Vav2和Vav3基因可能不是中国汉族PACG患者的易感基因。     

The evolution, complex structures and function of septin proteins

The septin family is a conserved GTP-binding protein family and was originally discovered through genetic screening for budding yeast mutants. Septins are implicated in many cellular processes in fungi and metazoa. The function of septins usually depends on septin assembling into oligomeric complexes and highly ordered polymers. The expansion of the septin gene number in vertebrates increased the complex diversity of septins. In this review, we first discuss the evolution, structures and assembly of septin proteins in yeast and metazoa. Then, we review the function of septin proteins in cytokinesis, membrane remodeling and compartmentalization.