Copper, zinc superoxide dismutase plus hydrogen peroxide: a catalytic system for human lipoprotein oxidation

We report for the first time that bovine or human CuZnSOD plus H2O2 can catalyze human lipoprotein oxidation, inducing like free copper ions a typical oxidative kinetics with lag and propagation phases. Free copper released from CuZnSOD by H2O2, but not enzyme peroxidase activity and carbonate radical anion, is responsible for lipoprotein oxidation, which is indeed totally inhibited by copper chelators and BHT but unaffected by bicarbonate. Moreover, lipoprotein oxidation is significantly counteracted by the OH* scavengers formate and azide, which can enter the active site of CuZnSOD and decrease copper release through scavenging of copper-bound OH*; benzoate and ethanol, which cannot enter, are instead ineffective, indicating no oxidative involvement of free OH* escaped from the enzyme active site. The possibility of CuZnSOD/H2O2-catalyzed lipoprotein oxidation in vivo is discussed.     

O-Specific chain structure from the lipopolysaccharide fraction of Pseudomonas reactans: a pathogen of the cultivated mushrooms

An O-specific polysaccharide containing 2-acetamidino-2-deoxy-beta-D-glucopyranose (Glcp2Am), 2,4-diacetamido-2,4,6-trideoxy-beta-D-glucopyranose (QuipNAc4NAc, bacillosamine) and 2,4-di-(N-acetyl-L-alanylamino)-2,4,6-trideoxy-beta-D-glucopyranose (QuipNAlaAc4NAlaAc) was isolated from the phenol-soluble lipopolysaccharide fraction of the mushroom-associated bacterium Pseudomonas reactans. The structure, determined by means of chemical analysis and 1D and 2D NMR spectroscopy, showed a linear trisaccharide-repeating unit, as shown below:-->3)-beta-D-QuipNAlaAc4NAlaAc-(1-->3)-alpha-D-Glcp2Am-(1-->3)-alpha-D-QuipNAc4NAc(1-->To our knowledge, this is the first complete O-chain structure reported for the lipopolysaccharide of a mushroom-associated bacterium.     

An immunotoxin containing a rat IgM monoclonal antibody (Campath 1) and saporin 6: effect on T lymphocytes and hemopoietic cells

Summary The elimination of the cells responsible for graft-versus-host disease in allogeneic bone marrow transplantation has been attempted with a variety of methods, including the use of the ribosome-inactivating toxin ricin bound to monoclonal antibodies acting as carriers. However the high nonspecific toxicity of these immunotoxins containing the whole toxin greatly limited clinical application. Toxicity can be reduced using the A-chain of ricin or other ribosome-inactivating proteins (RIPs) which are devoid of a B-chain with lectin properties. We used saporin 6 purified from Saponaria officinalis seeds, which was conjugated with the rat IgM monoclonal antibody Campath 1 specific for mature T and B lymphocytes as well as for monocytes. The immunotoxin retained both RIP and antibody activity, inhibiting protein synthesis both in a cellfree system and in cells bearing the Campath 1 antigen; it also abolished methyl ³H-thymidine uptake in phytohemagglutinin-stimulated T lymphocytes. Myeloid progenitors were largely spared as shown by myeloid stem cell (CFUGM) growth which was scarcely affected. Toxicity of the immunotoxin to cell lines not expressing the antigen recognized by Campath 1 monoclonal antibody was not greater than the toxicity due to free saporin 6, while the immunotoxin was more toxic to mice than free saporin.Work supported by grants of Regione Emilia Romagna, delibera n. 1970, 13/5/86, by the Italian National Research Council, Roma, Finalized Project Oncologia, contracts n. 86.00589.44 and n. 86.00603.44 and by the Pallotti's Legacy for Cancer ResearchAngelo Dinota is supported by a grant from Associazione Italiana per la Ricerca sul Cancro (AIRC), Milan, Italy.     

Structural determination of lipid A of the lipopolysaccharide from Pseudomonas reactans. A pathogen of cultivated mushrooms.

The chemical structure of lipid A from the lipopolysaccharide of the mushroom-associated bacterium Pseudomonas reactans, a pathogen of cultivated mushroom, was elucidated by compositional analysis and spectroscopic methods (MALDI-TOF and two-dimensional NMR). The sugar backbone was composed of the beta-(1'-->6)-linked d-glucosamine disaccharide 1-phosphate. The lipid A fraction showed remarkable heterogeneity with respect to the fatty acid and phosphate composition. The major species are hexacylated and pentacylated lipid A, bearing the (R)-3-hydroxydodecanoic acid [C12:0 (3OH)] in amide linkage and a (R)-3-hydroxydecanoic [C10:0 (3OH)] in ester linkage while the secondary fatty acids are present as C12:0 and/or C12:0 (2-OH). A nonstoichiometric phosphate substitution at position C-4' of the distal 2-deoxy-2-amino-glucose was detected. Interestingly, the pentacyl lipid A is lacking a primary fatty acid, namely the C10:0 (3-OH) at position C-3'. The potential biological meaning of this peculiar lipid A is also discussed.     

Role of biophysical parameters on ex vivo and in vivo gene transfer to the airway epithelium by polyethylenimine/albumin complexes

Efficient gene transfer to the airways by nonviral vectors is a function of different parameters, among which the size and the charge of the transfecting particles. The aim of this study was to determine the transfection efficiency of polyethylenimine (PEI)/albumin polyplexes in ex vivo and in vivo models of respiratory epithelium and to correlate it with biophysical characteristics of the particles. Complexes were obtained by adding different amounts of human serum albumin (HSA) to PEI polyplexes preformed in saline. The presence of HSA caused the formation of bigger and more negative polyplexes and increased PEI transfection efficiency in primary respiratory epithelial cells by 4-6-fold. For in vivo administration to the lung, PEI polyplexes were formed in water and optimized with respect to the N/ P ratio. PEI/pC-Luc complexes gave the highest luciferase expression at N/ P 15 when administered through the trachea. At this N/ P ratio, the size and the surface charge of albumin-containing polyplexes were not different as compared with plain PEI polyplexes. Formulation of PEI polyplexes in the presence of HSA or murine serum albumin (MSA) resulted in a 2-fold increase in luciferase expression. In mice treated with PEI or PEI/MSA polyplexes containing the nuclear beta-gal gene, X-gal staining revealed that transfected cells localized at the bronchiolar epithelium and that PEI/MSA transfected four times as many cells as PEI ( p < 0.05). Finally, double administration of PEI/MSA polyplexes resulted in a further enhancement of transfection of the lung. Our data show that serum albumin enhances PEI-mediated gene transfer to airway epithelial cells in vivo, likely facilitating the uptake of polyplexes, and indicate that this formulation would fulfill the requirement of repeated administration, as necessary in chronic lung diseases like cystic fibrosis.     

Accelerated aging phenotype in mice with conditional deficiency for mitochondrial superoxide dismutase in the connective tissue

The free radical theory of aging postulates that the production of mitochondrial reactive oxygen species is the major determinant of aging and lifespan. Its role in aging of the connective tissue has not yet been established, even though the incidence of aging-related disorders in connective tissue-rich organs is high, causing major disability in the elderly. We have now addressed this question experimentally by creating mice with conditional deficiency of the mitochondrial manganese superoxide dismutase in fibroblasts and other mesenchyme-derived cells of connective tissues in all organs. Here, we have shown for the first time that the connective tissue-specific lack of superoxide anion detoxification in the mitochondria results in reduced lifespan and premature onset of aging-related phenotypes such as weight loss, skin atrophy, kyphosis (curvature of the spine), osteoporosis and muscle degeneration in mutant mice. Increase in p16(INK4a) , a robust in vivo marker for fibroblast aging, may contribute to the observed phenotype. This novel model is particularly suited to decipher the underlying mechanisms and to develop hopefully novel connective tissue-specific anti-aging strategies.     

Quality of life and related factors among HIV-positive spouses from serodiscordant couples under antiretroviral therapy in Henan Province, China

Objective

To describe the quality of life and related factors in HIV-positive spouses undergoing ART from discordant couples.

Methods

A cross-sectional study was conducted among 1,009 HIV-positive spouses from serodiscordant couples in Zhumadian, Henan Province, between October 1, 2008 and March 31, 2009. HIV-positive spouses were interviewed by local health professionals. Quality of life was evaluated by WHOQOL (Chinese Version). A multiple linear regression model was used to analyze the related factors.

Results

The majority of subjects were female (56.39%), had received a high school education (44%), were of Han ethnicity (98.41%), and were farmers (90.09%); the median time period of receiving ART was 3.92 years. The physical, psychological, social, and environmental QOL scores of the subjects were 12.91±1.95, 12.35±1.80, 13.96±2.43, and 12.45±1.91 respectively. The multiple linear regression model identified the physical domain related factors to be CD4 count, educational level, and occupation; psychological domain related factors include age, educational level, and reported STD symptom; social domain related factors included education level; and environmental domain related factors included education level, reported STD symptoms, and occupation.

Conclusion

Being younger, a farmer, having a lower level of education, a reported STD symptom, or lower CD4 count, could decrease one''s quality of life, suggesting that the use of blanket ART programs alone may not necessarily improve quality of life. Subjects received lower scores in the psychological domain, suggesting that psychological intervention may also need to be strengthened.     

Malignant Lymphomas of Waldeyer's Ring: Natural History and Survival after Radiotherapy

The natural history of 292 consecutive cases of reticulum cell sarcoma and lymphosarcoma of Waldeyer''s ring and the survival rate after radiotherapy are reported. In our institute since 1928 from 30 to 35% of pharyngeal neoplasms have been lymphomas, and of these 55% have been reticulum cell sarcomas, 21% lymphosarcomas, and 1% Hodgkin''s disease. This high incidence may probably be ascribed to the fact that in all malignant lymphomas, irrespective of the clinical presentation, a systematic biopsy of the whole Waldeyer''s ring was carried out. Pharyngeal lymphomas were confined to Waldeyer''s ring in 19·6% of cases, with initial spread to contiguous cervical nodes in 43·8%, to distant nodes in 24·2%, and to extranodal tissues in 12·4%. Lymphography showed abnormal retroperitoneal lymph nodes in 38·3% of cases. There was gastrointestinal involvement either initially or later in 17·6% of cases. High-energy radiation therapy to both sides of the neck was the treatment of choice for local and regional disease. It achieved a five-year survival rate of 41·9% in the group of 97 patients treated during the past decade. The incidence of relapse (recurrence and new manifestations) was highest in the first year after treatment.