Two immunologically distinct human acidic beta-galactosidase A isozymes

Two acidic beta-galactosidase isozymes (designated A1 and A2) were separated by isoelectric focusing from beta-galactosidase A of human liver. Kinetic studies with 4-methylumbelliferyl-beta-D-galactopyranoside substrate revealed similar parameters for both. The Km value was 0.32 mmol/1 for A1 and 0.30 mmol/1 for A2 and Vmax values of 59.3 and mumol min-1 mg-1, respectively. The pH optimum was 4.2 for beta-galactosidase A1 and 4.5 for the A2 form. The A1 enzyme form was shown to be more heat labile than the A2. Significant differences were observed with antibody preparations against the two enzyme forms. Using the anti-A1 antibodies two precipitin arcs with residual enzymatic activity were obtained by immunoelectrophoresis of beta-galactosidase A whereas only one with anti-A2 antibodies. Anti-A1 precipated 85% of the original activity present in beta-galactosidase A and only 56% could be precipated by anti-A2. The possibility of common structural components is suggested.     

Synthesis of Leishmania cap-4 intermediates, cap-2 and cap-3

Synthesis of Leishmania mRNA 5'-cap analogs, m(7)Gpppm(2)(6)AmpAm (cap-2), and m(7)Gpppm(2)(6)AmpAmpCm (cap-3) is reported. Binding affinities of those cap analogs for LeishIF4E proteins were determined using fluorescence spectroscopy. Cap-3 showed similar affinity to LeishIF4Es compared to the mature trypanosomatids cap structure (cap-4).     

Foam cell‐derived 4‐hydroxynonenal induces endothelial cell senescence in a TXNIP‐dependent manner

Vascular endothelial cell (VEC) senescence is considered an early event in the development of atherosclerotic lesions. Stressful stimuli, in particular oxidative stress, have been linked to premature senescence in the vasculature. Foam cells are a major source of reactive oxygen species and may play a role in the induction of VEC senescence; hence, we investigated their involvement in the induction of VEC senescence in a co‐culture transwell system. Primary bovine aortic endothelial cells, exposed to the secretome of THP‐1 monocyte‐derived foam cells, were analysed for the induction of senescence. Senescence associated β‐galactosidase activity and the expression of p16 and p21 were increased, whereas phosphorylated retinoblastoma protein was reduced. This senescent phenotype was mediated by 4‐hydroxnonenal (4‐HNE), a lipid peroxidation product secreted from foam cells; scavenging of 4‐HNE in the co‐culture medium blunted this effect. Furthermore, both foam cells and 4‐HNE increased the expression of the pro‐oxidant thioredoxin‐interacting protein (TXNIP). Molecular manipulation of TXNIP expression confirmed its involvement in foam cell‐induced senescence. Previous studies showed that peroxisome proliferator‐activated receptor (PPAR)δ was activated by 4‐hydroalkenals, such as 4‐HNE. Pharmacological interventions supported the involvement of the 4‐HNE‐PPARδ axis in the induction of TXNIP and VEC senescence. The association of TXNIP with VEC senescence was further supported by immunofluorescent staining of human carotid plaques in which the expression of both TXNIP and p21 was augmented in endothelial cells. Collectively, these findings suggest that foam cell‐released 4‐HNE activates PPARδ in VEC, leading to increased TXNIP expression and consequently to senescence.     

Effects of subinhibitory concentrations of menthol on adaptation, morphological, and gene expression changes in enterohemorrhagic Escherichia coli

Menthol (C(10)H(20)O) possesses antibacterial activity; nevertheless, bacterial adaptation to this compound has never been studied. Here we report that precultivation of enterohemorrhagic Escherichia coli (EHEC) strains in increasing subinhibitory (SI) concentrations of menthol significantly elevates (4- to 16-fold) their resistance to menthol. Concomitant morphological alterations included the appearance of mucoid colonies and reduced biofilm production. Scanning electron microscopy (SEM) examination revealed suppressed curli formation in menthol-adapted cells. Expression of the gene cpsB10 (encoding one of the enzymes responsible for colanic acid production) was elevated in response to SI concentrations of menthol in a laboratory E. coli strain, whereas expression in an rcsC null mutant was reduced, implicating a partial role for the Rcs phosphorelay system in mediating the menthol signal. Adaptation to menthol also reduced expression of the locus of enterocyte effacement-encoded regulator (Ler). This reduction, together with reduced curli and biofilm formation and elevated mucoidity, suggests a general reduction in bacterial virulence following adaptation to menthol. Our results thus suggest menthol as a potential lead in the recently emerging alternative strategy of targeting bacterial virulence factors to develop new types of anti-infective agents.     

TCR zeta down-regulation under chronic inflammation is mediated by myeloid suppressor cells differentially distributed between various lymphatic organs

T cell AgR zeta chain down-regulation associated with T cell dysfunction has been described in cancer, infectious, and autoimmune diseases. We have previously shown that chronic inflammation is mandatory for the induction of an immunosuppressive environment leading to this phenomenon. To identify the key immunosuppressive components, we used an in vivo mouse model exhibiting chronic inflammation-induced immunosuppression. Herein, we demonstrate that: 1) under chronic inflammation secondary lymphatic organs display various immunological milieus; zeta chain down-regulation and T cell dysfunction are induced in the spleen, peripheral blood, and bone marrow, but not in lymph nodes, correlating with elevated levels of Gr1(+)Mac-1(+) myeloid suppressor cells (MSC); 2) MSC are responsible for the induction of such an immunosuppression under both normal and inflammatory conditions; and 3) normal T cells administered into mice exhibiting an immunosuppressive environment down-regulate their zeta expression. Such an environment is anticipated to limit the success of immunotherapeutic strategies based on vaccination and T cell transfer, which are currently under investigation for immunotherapy of cancer.     

Complementary medicine in the primary care setting: Results of a survey of gender and cultural patterns in Israel

Objective: The purpose of this study was to examine the use of complementary and alternative medicine (CAM) in a primary care practice in Israel to determine prevalence and patterns of use.Methods: Trained research assistants invited all patients attending the administrative, medical, pharmaceutical, or nursing services of 7 clinics in urban and rural areas of northern Israel over a 16-month period, from April 1, 2005, through August 1, 2006, to complete a 13-item written questionnaire about CAM use and beliefs about CAM safety and efficacy. CAM was defined as therapies often referred to as alternative, complementary, natural, or folk/traditional medicine, and which are not usually offered as part of the medical treatment in the clinic, including herbal medicine, Chinese medicine (including acupuncture), homeopathy, folk and traditional remedies, dietary/nutritional therapy (including nutritional supplements), chiropractic, movement/manual healing therapies (including massage, reflexology, yoga, and Alexander and Feldenkrais techniques), mind-body techniques (including meditation, guided imagery, and relaxation), energy and healing therapies, and other naturopathic therapies. The Pearson χ² test and multivariate logistic regression were used to assess univariate associations with the odds ratios of CAM use among Arab and Jewish women. A t test was performed to determine whether there were any differences in the continuous variables between the 2 groups.Results: Of 3972 consecutive patients who received the questionnaire, 3447 responded; 2139 respondents (62%) were women. Of the female respondents, 2121 reported their religion (1238 respondents [58%] self-identified as being Arab, and 883 [41.6%] as being Jewish). Compared with men, more women used CAM during the previous year (46.4% vs 39.4%; P < 0.001). Women were more likely to use CAM and to be interested in receiving CAM at primary care clinics. Arab women reported less CAM use than Jewish women but were more interested in experiencing CAM, had a higher degree of confidence in CAM efficacy and safety, and more frequently supported the integration of CAM practitioners in primary care clinics.Conclusions: In this study, women visiting primary care clinics in northern Israel used CAM more often than men did. Arab women reported less use of CAM than did Jewish women but also reported greater confidence in CAM efficacy and safety.