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E Kiss

Publications and source records attributed to E Kiss.

At least 19 recordsLinked to original sources

Beneficial effects of CCR1 blockade on the progression of chronic renal allograft damage.

The biology of chemokines and their receptors have been linked to the development of chronic allograft damage. Effects of CCR1 antagonist BX 471 were studied in a Fischer to Lewis renal transplantation model at days 10, 21 and 42 after transplantation. BX 471 treatment did not effectively reduce signs of acute rejection at day 10 but significantly improved allograft function and morphology at day 21 posttransplantation. When therapy was initiated on day 21 after transplantation, glomerulosclerosis and tubulointerstitial fibrosis were significantly inhibited by day 42 posttransplantation. Parallel decrease in infiltrating and proliferating mononuclear cells (ED1, CD8 and Ki67) was observed in treated allografts. Expression of acute phase reactive and proinflammatory genes (HO-1, osteopontin) and molecules associated with fibrosis (PAI-1, TGF-beta1, biglycan) was downregulated at day 21; reduced collagen deposition was observed, parallel to a significant lower number of alpha-SMA+ interstitial myofibroblasts. In situ hybridization demonstrated that biglycan expression was reduced following CCR1 blockade in interstitium of treated allografts. CCR1 antagonism was found to inhibit CCL5-induced secretion of biglycan by macrophages in vitro. CCR1 blockade significantly inhibited development and progression of chronic allograft damage. CCR1 antagonists may represent a therapeutic option for chronic inflammation and fibrosis in renal grafts.

Animals↗

Association study of the adrenergic receptors and childhood-onset mood disorders in Hungarian families.

The adrenergic system has been implicated in the etiology of depression based on a number of lines of evidence, particularly, the mechanism of some classes of antidepressants which increase the synaptic levels of norepinephrine. Further, several genome scans for mood disorders, both unipolar and bipolar, have indicated linkage to the chromosomal regions of 5q23-q33.3, 8p12-p11.2, 4p16, and 10q24-q26, the location of the adrenergic receptors alpha1B (ADRA1B), beta3 (ADRB3), alpha2C (ADRA2C), alpha2A (ADRA2A), and beta1 (ADRB1). In this manuscript, we report on the relationship of the adrenergic receptors and depression using a family based association approach and 189 families (223 affected children) with childhood-onset mood disorder (COMD) collected in Hungary. We found no significant evidence for an association with any of the 24 markers, in total, tested across these genes using single marker analysis or haplotypes of markers across these genes. The results in the present sample indicate that these nine genes are unlikely to be major susceptibility genes contributing to COMD.

Adolescent↗

Significant correlation between the CD63 assay and the histamine release assay in chronic urticaria.

BACKGROUND: Antibodies directed to the alpha subunit of the high affinity IgE receptor and the IgE molecule are proposed to be of pathogenetic relevance in a group of patients with chronic urticaria (CU). The diagnosis of autoimmune chronic urticaria (ACU) is difficult; the autologous serum skin test (ASST) seems to be a useful screening test, but reliable, additional confirmatory methods are needed. OBJECTIVES: To assess the diagnostic value of a modified serum-induced basophil activation test, the CD63 expression assay, in the diagnosis of ACU by comparing the results of the CD63 assay with the results of the histamine release (HR) test, the ASST and serum levels of soluble CD40 ligand (sCD40L). METHODS: Using basophils from an atopic (DA) and a nonatopic (DNA) donor the activity of sera of 72 patients with CU were measured in HR assay by enzyme-linked immunosorbent assay and in CD63 expression assay by flow cytometry. An ASST was carried out in all patients; in 30 of the 72 patients sCD40L was detected and correlations were derived between the different assays. Sera of 20 normal controls and 26 patients with systemic autoimmune diseases were also tested in the HR assay and in the CD63 expression assay. RESULTS: Histamine-releasing activity was detected in the sera of 51% (DA) and 32% (DNA) of CU patients and 57% (DA) and 28% (DNA) of sera upregulated CD63 expression on the surface of basophils from the different donors. There was a significant correlation between the HR and the CD63 assays carried out on both donors, but the ASST showed a strong correlation with the HR assay only for basophils from the DA. The serum level of sCD40L was significantly higher in patients with CU compared with controls, but the difference between the autoimmune and the nonautoimmune groups was not significant. CONCLUSIONS: The CD63 expression assay seems to be a reliable functional test in the diagnosis of ACU, particularly if highly sensitive donor basophils are used, but the determination of the sCD40L serum level was not sufficient to differentiate between the autoimmune and the nonautoimmune patient groups.

Adolescent↗

Retrospective analysis of patients with lupus nephritis: data from a large clinical immunological center in Hungary.

The aim of this study was to review the development, histological type and outcome of 117 patients with lupus nephritis managed and followed by the Division of Clinical Immunology, 3rd Department of Internal Medicine, University of Debrecen, Debrecen, Hungary. The method used was a retrospective study in 117 patients with lupus nephritis followed between 1974 and 2004. The average occurrence of lupus nephritis was 3 (women) and 4.4 (men) years later after the diagnosis of systemic lupus erythematosus, 43 (46.2%) patients had class IV lupus nephritis. The initial therapy was intravenous cyclophosphamide treatment for 6 months in 37 (31.6%) patients. End-stage renal disease had developed in nine (7.6%) patients. The 5-year survival rate was 99.1%. Despite the well-known and proved risk factors like hypertension, high serum creatinine, renal failure at onset or membranous glomerulonephritis, the outcome of the disease in our patient population was more favourable than one would expect according to the data available in the literature. The authors would like to draw attention to the importance of systematic care of patients with systemic lupus erythematosus, which may lead to a better clinical outcome.

Adult↗

Low variability of internal transcribed spacer rDNA and trnL (UAA) intron sequences of several taxa in the Festuca ovina aggregate (POACEAE).

Identification and classification of numerous Festuca species is still a difficult problem due to the close morphological resemblance. The most difficult fine fescues to identify belong to the Festuca ovina aggregate, which is the largest group in the genus Festuca. Many taxons are considered to be separate species based on quantitative taxonomic characters, differences in ploidy level or the structure of sclerenchyma cells. In order to evaluate the taxonomic value of DNA-based markers, sequence analysis of the internal transcribed spacer (ITS1-5.8S-ITS2) region and the chloroplast trnL (UAA) intron was performed in the ten most problematic fine fescues belonging to the Festuca ovina aggregate. Intraspecific ITS variants were found in a single case while in other cases only intragenomic ITS polymorphisms were detected with 1-2 ambiguous positions. Among the sequences of the trnL (UAA) intron even intragenomic polymorphisms were not detected in any of the Festuca species studied. Thus, the results do not support the species status of these ten taxa.

Base Sequence↗

Association study of CREB1 and childhood-onset mood disorders.

Several lines of evidence suggest that the cellular pathways involved in synaptic plasticity contribute to the risk of depression. These findings include the evidence that chronic antidepressant treatment upregulates the cAMP signal transduction cascade resulting in increased expression and function of the cAMP responsive element binding protein (CREB), a transcription factor that increases the expression of key growth factors involved in synaptogenesis and neurogenesis. Recently, linkage to CREB1 was reported for early-onset depression in families recruited from the Pittsburgh area. This finding was significant only in female sibling pairs from those families. Two specific DNA variants, -656G/A and a C insertion/deletion in intron 8, were identified in CREB1 that co-segregated with depression in two of the families. We sought to investigate the relationship of CREB1 to childhood-onset mood disorders (COMD) using a sample of 195 nuclear families (225 affected children) collected in Hungary. We genotyped the two CREB1 DNA variants previously identified as linked to depression as well as three additional polymorphisms spanning the gene. In addition, we genotyped the -656G/A DNA change and the intron 8 polymorphism in a sample of 112 probands with mood disorders collected in the Pittsburgh area and matched controls, and examined the distribution of alleles. The -656A allele was not observed in our samples and there was no evidence for association of the intron 8 polymorphism in either the sample from Pittsburgh (chi(2) = 0.061, 1 d.f., P = 0.803) or Hungary (chi(2) = 0.040, 1 d.f., P = 0.842). We found no evidence for an association with the other three polymorphisms or with the haplotypes of these markers. Further, we found no sex-specific relationship. Our results, therefore, do not support the previous evidence for this gene as a major factor contributing to depression.

Adolescent↗

Ultraviolet-A1 phototherapy modulates Th1/Th2 and Tc1/Tc2 balance in patients with systemic lupus erythematosus.

OBJECTIVE: Ultraviolet-A1 (UVA1) phototherapy is effective for a variety of dermatological diseases. We examined the effectiveness and reliability of low-dose UVA1 phototherapy (60 kJ/m2/treatment) in patients suffering from systemic lupus erythematosus (SLE). We studied the changes in immunological parameters. METHODS: The patients received a 9-week course of phototherapy according to the following regimen: five times a week during the first 3 weeks, three times a week during the second 3 weeks and twice during the last 3 weeks. Among other things, we analysed the proportions of T helper 1 (Th1), Th2, T cytotoxic (Tc1) and Tc2 cell populations in the peripheral blood of patients by flow cytometric detection of intracytoplasmic interferon gamma (IFN-gamma) and interleukin 4 (IL-4). RESULTS: Our study showed the improvement of clinical symptoms determined by the subjective clinical disease activity scoring and the SLE Disease Activity Index (SLEDAI). By the end of UVA1 phototherapy, the mean value of SLEDAI had decreased from 7.2+/-5.6 to 0.9+/-1.8, which was significant (P = 0.005). Immunological investigations detected a decrease in the frequency of IFN-gamma-producing Th1 and Tc1 cells and a decrease in the Th1/Th2 and Tc1/Tc2 ratios after UVA1 therapy. CONCLUSION: According to the literature, IFN-gamma has a pathogenic role in the development of SLE. We observed a decreased proportion of IFN-gamma-secreting cells, which we think is presumably one of the beneficial effects of UVA1 therapy. On the basis of our study, UVA1 phototherapy does seem to be an effective adjuvant in the treatment of SLE patients.

Adult↗

Brain-derived neurotrophic factor variants are associated with childhood-onset mood disorder: confirmation in a Hungarian sample.

Brain-derived neurotrophic factor (BDNF) is a nerve growth factor that has been implicated in the neurobiology of depression. Our group has previously reported an association between a BDNF variant and childhood-onset mood disorder (COMD) in an adult sample from Pittsburgh. We hypothesize that variants at the BDNF locus are associated with COMD. Six BDNF polymorphisms were genotyped in 258 trios having juvenile probands with childhood-onset DSM-IV major depressive or dysthymic disorder. BDNF markers included the (GT)n microsatellite, Val66Met and four other single-nucleotide polymorphisms (SNPs) distributed across the BDNF gene. Family-based association and evolutionary haplotype analysis methods were used. Analysis of linkage disequilibrium (LD) revealed substantial LD among all six polymorphisms. Analyses of the Val66Met polymorphism demonstrated significant overtransmission of the val allele (chi2=7.12, d.f.=1, P=0.0076). Consistent with the pattern of LD, all other SNPs showed significant biased transmission. The (GT)n microsatellite alleles also indicated a trend towards biased transmission (170 bp: Z=2.095, P=0.036). Significant haplotypes involved Val66Met and BDNF2 (P=0.0029). In this Hungarian sample, we found all five BDNF SNPs tested and a haplotype containing the BDNF Val66Met Val allele to be associated with COMD. These results provide evidence that BDNF variants affect liability to juvenile-onset mood disorders, supported by data from two independent samples.

Adult↗

[Autoimmune cholangitis with vasculitic ulcers, rheumatoid arthritis and IgA glomerulonephritis].

HISTORY AND ADMISSION FINDINGS: A 51-year-old woman was admitted because of relapsing episodes of fever and leg ulcers for 14 years. In addition, she had polyserositis, polyarthralgias and polyarthritides, renal failure with proteinuria and elevation of gamma-GT and alkaline phosphatase. The patient was in a reduced general condition and cachectic nutritional state. She had slight scleral icterus, the liver being palpable 5 cm under the costal margin, edema of the lower limbs and two ulcers at the right foot. INVESTIGATIONS: Laboratory examinations revealed leukocytosis, anemia, elevation of cholestasis and inflammation parameters as well as renal failure. During a 24 hour collection period, a significant proteinuria was demonstrated. Immunoserologically, an ANA titer of 1:100 and a positive rheumatoid factor were found, ANCAs and AMAs were negative. On ultrasound, both kidneys exhibited a blurred pelvic parenchymal border. Thyroid ultrasound demonstrated parenchymal changes consistent with Hashimoto's disease. Ultrasound of the wrist revealed extensive arthritis with tendovaginitis. A renal biopsy revealed mesangioproliferative glomerulonephritis. DIAGNOSIS, THERAPY AND CLINICAL COURSE: Due to serologically persistent cholestasis, a liver biopsy was performed which, together with negative AMAs, revealed the diagnosis of an autoimmune cholangitis (AIC; AMA-negative primary-biliary cirrhosis (PBC)). In addition, the patient presented with rheumatoid arthritis, polyserositis, IgA glomerulonephritis, vasculitic leg ulcers and Hashimoto's thyreoiditis which were interpreted as extra-hepatic manifestations of the AIC. After initiation of high dosage corticosteroid therapy, rapid healing of the leg ulcers occurred. Therapy of the AIC consisted in ursodeoxycholic acid. CONCLUSION: The multitude of associated immunological phenomena in this patient resulted in a delay of the diagnosis. A AIC/PBC, however, should, always be considered in case of cholestasis.

Adrenal Cortex Hormones↗

Increased titer of anti-beta2-glycoprotein I IgG antibody among factor V Leiden carriers during oral contraceptive use.

The risk of thromboembolism during oral contraceptive (OC) use is increased among factor V Leiden (FVL) carriers compared to women with wild-type genotype of the gene for coagulation factor V (FV). The carrier frequency in the general population is too high for FVL alone to be responsible for the reported association. Additional risk factors may be required to explain the increased risk of thromboembolism of carriers during OC use. We conducted a case-control study to compare the titer of anti-beta2-glycoprotein I immunoglobulin G (IgG) and the frequency of elevated titer of IgG type anti-beta2-glycoprotein I antibody between FVL carriers and individuals with FV wild-type genotype with and without pill use. An asymptomatic population of 313 unrelated nonpregnant women were screened for FVL and for the presence of anti-beta2-glycoprotein I IgG antibody. Sixty-six women were FVL carriers and 247 had normal genotype. One-hundred and thirty-five women used OC at the time of screening and 178 did not. Among FVL carriers, OC pill users had a higher mean anti-beta2-glycoprotein I IgG titer than nonusers (9.2 SGU/mL vs. 4.7 SGU/mL, p = 0.0485). Among women with FV wild-type genotype, there was no significant difference in anti-beta2-glycoprotein I IgG titers between users and nonusers of OCs (6.4 SGU/mL and 6.0 SGU/mL, respectively; p = 0.7010). The odds of an elevated anti-beta2-glycoprotein I IgG titer during OC use in FVL heterozygous women was 2.41 (95% confidence interval: 0.79-7.39) relative to users with-type genotype. FVL may contribute to the development of elevated titer of IgG type anti-beta2-glycoprotein I antibody during OC use. The elevated titer of IgG type anti-beta2-glycoprotein I antibody may select women among FVL carriers during OC use with an increased risk of thromboembolism.

Adult↗

Abnormal cell-specific expressions of certain protein kinase C isoenzymes in peripheral mononuclear cells of patients with systemic lupus erythematosus: effect of corticosteroid application.

We have studied the expressions of various protein kinase C (PKC) isoenzymes in T cells and monocytes from patients with systemic lupus erythematosus (SLE), in comparison to those of healthy controls and patients with other immunological disorders. As measured by Western blotting, the levels of PKCbeta, delta, eta, epsilon, theta and zeta (but not of PKCalpha) significantly decreased in T cells of SLE patients. In monocytes, however, we observed marked suppressions only in the expressions of PKCdelta, epsilon and zeta but not in the expressions of other PKC isoforms. In vivo corticosteroid application, as well as in vitro steroid treatment of monocytes, elevated the expressions of most isoforms close to normal values; however, the decreased levels of PKCtheta and zeta were not affected by steroid application. These alterations were characteristic to SLE because we could not detect any changes in the PKC levels in mononuclear cells of primary Sjögren's syndrome and mixed connective tissue disease patients. These results suggest that impaired PKC isoenzyme pattern may exist in the T cells and monocytes of SLE patients. Furthermore, the clinically efficient glucocorticoid application in SLE can increase the expression of some members of PKC system.

Adrenal Cortex Hormones↗

Basophil CD63 expression assay on highly sensitized atopic donor leucocytes-a useful method in chronic autoimmune urticaria.

BACKGROUND: The autoimmune subclass of chronic idiopathic urticaria (CU) has been characterized by the occurrence of biologically relevant IgG antibodies against the IgE molecule or the alpha chain of the high-affinity Fcepsilon receptor (FcepsilonRIalpha) on basophils and mast cells. These antibodies are usually detected by autologous serum skin testing and confirmed by histamine release studies, immunoblotting, or enzyme-linked immunosorbent assay, but not always. OBJECTIVES: To detect autoantibodies to the FcepsilonRIalpha in sera of CU patients by a modified serum-induced basophil activation test measured by flow cytometry (FCM) and to evaluate the relationship between the in vitro functional test, the autologous serum skin test (ASST), and the serum levels of IgE, eosinophil cationic protein (ECP) and antithyroid antibodies. METHODS: Sera of 30 patients with CU and 26 patients with systemic autoimmune diseases (systemic lupus erythematosus, dermatomyositis) were tested for CD63 activation marker expression on basophils by FCM. Leucocytes from two highly sensitized atopic donors (D(A1,) D(A2)) and one non-atopic donor (D(NA)) were incubated with patients' sera and double-labelled with anti-IgE and anti-CD63 antibodies. Subsequently, the percentage of CD63-expressing basophils was determined by using FCM. In all CU patients an ASST was carried out and the serum IgE, and ECP levels and antithyroid antibodies were evaluated. RESULTS: Twelve patients had a positive ASST and 14 patients a positive CD63 expression assay. There was a strong correlation between the ASST and CD63 assay. Sera from patients with systemic autoimmune diseases did not raise positive CD63 expression on basophils. There was a moderate negative correlation between the occurrence of atopic serum markers (IgE, ECP) and the ability of sera to induce CD63 expression on basophil cells of D(A2) (P < 0.05). The female sex was preponderant and antithyroid antibodies were more frequent. CONCLUSIONS: Our new technical observation demonstrates that basophils of highly sensitized atopic donors can be successfully used without priming with IL-3 for the in-vitro flow cytofluorimetric diagnosis of CU. With this investigation the characterization of the autoimmune origin of CU is based on an objective in vitro technique.

Adolescent↗

Budapest Student Health Behavior Survey--Budapest, Hungary, 1999. Findings on unintentional and intentional injuries, alcohol use, and sexual activity.

OBJECTIVE: In Hungary, a large proportion of adult morbidity and mortality can be attributed to health risk behaviors that begin in early adolescence. To date, studies examining health risk behaviors among youth have rarely been undertaken in Hungary. In order to expand current research in this area, the Hungarian Metropolitan Institute of State Public Health and Public Health Officer Service and the Office on Smoking and Health at the U.S. Centers for Disease Control and Prevention developed and implemented the Budapest Student Health Behavior Survey. The objective of this study was to examine health behavior risk factors among secondary school students in Budapest in 1999. METHODS: The 1999 Budapest Student Health Behavior Survey is cross-sectional school-based survey A 2-stage cluster sampling design was used to produce a representative sample of secondary students in grades 9-12 in Budapest. Information was collected on unintentional and intentional injuries, alcohol use, and sexual activity. FINDINGS: During the 30 days preceding the survey, 28.7% of students had rarely or never worn a seatbelt and 68.1% drunk alcohol. During the 12 months preceding the survey, 14.5% had been threatened or injured with a weapon, 12.9% experienced dating violence, and 13.5% seriously considered suicide. Of the 44.7% of students who had had sexual intercourse, 29.5% had > or = 4 sex partners. Of sexually active students, 50.4% had not used a condom at last sexual intercourse. CONCLUSION: Many secondary school students in Budapest practice behaviors that place them at risk for serious health problems both in the short and long-term. Programs and policies that adequately address such behaviors among secondary school students are needed to reduce subsequent morbidity and mortality.

Adolescent↗

The effect of 1-year transdermal estrogen replacement therapy on bone mineral density and biochemical markers of bone turnover in osteopenic postmenopausal systemic lupus erythematosus patients: a randomized, double-blind, placebo-controlled trial.

We studied the effect of 1-year transdermal estrogen replacement therapy (ERT) on bone mineral density (BMD) and biochemical markers of bone turnover in osteopenic postmenopausal systemic lupus erythematosus (SLE) patients in a randomized, double-blind, placebo-controlled trial. SLE patients were randomly allocated to treatment (estradiol; 50 microg transdermal 17beta-estradiol; n=15) or placebo ( n=17) group. Both groups received 5 mg continuous oral medroxyprogesterone acetate, 500 mg calcium and 400 IU vitamin D(3). L(1)-L(4) spine (LS), left femur and total hip BMD were measured at baseline and at 6 and 12 months. Serum osteocalcin (OC) and degradation products of C-terminal telopeptides of type-I collagen (CTx) levels were measured at baseline and 3, 6, 9, and 12 months. There was a significant difference in the percentage change of LS BMD at 6 months between the two groups (103.24+/-3.74% (estradiol group) vs 98.99+/-3.11% (placebo group); P<0.005). There was a significant decrease within the estradiol group in the CTx levels between baseline and all subsequent visits ( P<0.05). There was no significant difference in SLE disease activity index, Systemic Lupus International Collaborating Clinics/American College of Rheumatology (ACR) damage index and corticosteroid dose during the study period. Transdermal estradiol may prevent bone loss in postmenopausal SLE women at the lumbar spine and femur, with no increase in disease activity among postmenopausal SLE women receiving transdermal ERT. The high dropout rate (8/15) leads us to the conclusion that efficacy of HRT in a high-risk group such as SLE women can be attained only in a small number of patients, provided all inclusion/exclusion criteria are strictly adhered to.

Administration, Cutaneous↗

Development of a non-lethal selection system by using the aadA marker gene for efficient recovery of transgenic rice (Oryza sativa L.).

The application of aminoglycoside-3"-adenyltransferase ( aadA) gene-mediated streptomycin resistance for non-lethal selection of transgenic rice resulted in plant regeneration frequencies under selection pressure as high as those in non-transformed controls without selection. Since streptomycin does not kill non-transgenic cells, and allows plant regeneration from them, a selection procedure was developed that made the visual identification of transgenic calli and regenerants possible. For callus-level selection, a vital pH indicator-Chlorophenol Red-was applied together with streptomycin, making use of the phenomenon that fast-growing cell lines lower the pH in the culture medium. Transgenic plants were selected according to their main distinctive features; their green colour (photomixotrophic assimilation), and more intense growth. At the same time, non-transgenic regenerants were bleached (heterotrophic assimilation), and growth was retarded in the presence of streptomycin and sucrose. The final efficiency of genetic transformation based on streptomycin resistance was found to be double that of transformations where the selective agent was l-phosphinothricin, and nearly three times more compared to transformations resulting in hygromycin-resistant regenerants. To the best of our knowledge, this is the first report on producing nuclear transformed rice plants by using a non-lethal selection strategy based on the chimaeric aadA gene.

Aminobutyrates↗

Evaluation of clinical and laboratory features of antiphospholipid syndrome: a retrospective study of 637 patients.

We retrospectively analysed the data of 1519 antiphospholipid antibody (APLA) positive patients between 1986 and 1999. Among them 637 were considered to have antiphospholipid syndrome (APS) based on the 1999 preliminary classification criteria, while 704 patients had no clinical signs of the syndrome. Our aim was to compare the autoantibody profile and clinical characteristics of primary and secondary APS, moreover to evaluate the associations between different APLA and specific symptoms attributable to APS. In our results, the APLA profiles for primary and SLE-associated secondary APS were similar. Among the evaluated clinical symptoms, cerebrovascular thrombosis was found to be more frequent in the SLE-associated, than in the primary APS group (P = 0.04). We identified important differences in the clinical profile of patient populations with various types of APLA. Venous thrombosis occurred more frequently in subjects withlupus anticoagulant (LA), than in those with IgG or IgM type ACLA (P < 0.0001), while coronary, carotid and peripheral artery thrombosis occurred more often in subjects with IgG or IgM ACLA (P < 0.0001). These findings may support the role of antibodies to cardiolipin or its cofactor, beta2glycoprotein I (beta2-GPI) in the initiation and progression of atherosclerosis. Cerebrovascular thrombosis was detected in larger proportion of LA or IgG ACLA-positive patients compared with to IgM ACLA-positive subjects, while the occurrence of foetal loss was similar in all three groups.

Antibodies, Anticardiolipin↗

XPS and wettability characterization of modified poly(lactic acid) and poly(lactic/glycolic acid) films.

Poly(lactic acid) (PLA) and poly(lactic/glycolic acid) copolymers (PLGA) are biodegradable drug carriers of great importance, although successful pharmaceutical application requires adjustment of the surface properties of the polymeric drug delivery system to be compatible with the biological environment. For that reason, reduction of the original hydrophobicity of the PLA or PLGA surfaces was performed by applying a hydrophilic polymer poly(ethylene oxide) (PEO) with the aim to improve biocompatibility of the original polymer. PEO-containing surfaces were prepared by incorporation of block copolymeric surfactants, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (Pluronic), into the hydrophobic surface. Films of polymer blends from PLA or PLGA (with lactic/glycolic acid ratios of 75/25 and 50/50) and from Pluronics (PE6800, PE6400, and PE6100) were obtained by the solvent casting method, applying the Pluronics at different concentrations between 1 and 9.1% w/w. Wettability was measured to monitor the change in surface hydrophobicity, while X-ray photoelectron spectroscopy (XPS) was applied to determine the composition and chemical structure of the polymer surface and its change with surface modification. Substantial reduction of surface hydrophobicity was achieved on both the PLA homopolymer and the PLGA copolymers by applying the Pluronics at various concentrations. In accordance with the wettability changes the accumulation of Pluronics in the surface layer was greatly affected by the initial hydrophobicity of the polymer, namely, by the lactide content of the copolymer. The extent of surface modification was also found to be dependent on the type of blended Pluronics. Surface activity of the modifying Pluronic component was interpreted by using the solubility parameters.

Journal Article↗

Bone mineral density in women with systemic lupus erythematosus.

The aim of this cross-sectional study was to determine the prevalence of reduced bone mineral density (BMD) in a group of female SLE patients and to identify factors predictive of reduced BMD. Femoral neck (FN) and lumbar spine (LS) dual-energy X-ray absorptiometry results were evaluated in 79 pre- and postmenopausal women with SLE aged (mean, range) 49 (22-73) years). Variables evaluated were disease duration, SLEDAI, current and cumulative corticosteroid dose, Steinbrocker's functional classification, use of immunosuppressive agents, and history of fracture due to minor trauma. A T-score of < or = 1.0 was found in 61.9% at the LS and 48.3% at the FN, and 18 (23.7%) patients belonged to the category of osteoporosis at LS, compared to only three (5.4%) patients at FN. A statistical difference (P = 0.014) was found when comparing LS BMD in pre- and postmenopausal patients. LS BMD had a significant correlation with daily and cumulative steroid dose (P = 0.016 and 0.031, respectively). There was a significant difference in LS BMD between the daily steroid dose group receiving < or = 7.5 and those receiving > 7.5 mg/day (P = 0.008), and also in FN BMD comparing groups on 0 and > 7.5 mg/day (P = 0.022). There was significant difference in LS and FN BMD between patients in Steinbrocker classes I and III (P = 0.016 and 0.005, respectively). No significant correlation was found in either subgroup between BMD and other studied parameters. We concluded that the prevalence of reduced bone mass at LS is pronounced among postmenopausal women with SLE, in those with a high Steinbrocker functional classification and those on a high daily steroid dose. Therefore, these patients should be considered as a high-risk group deserving regular spinal BMD scans and therapy in time to prevent vertebral fractures.

Absorptiometry, Photon↗