Protective effects of Rosmarinus tomentosus ethanol extract on thioacetamide-induced liver cirrhosis in rats

The capability of an ethanol extract of Rosmarinus tomentosus to protect rat liver in an experimental model of cirrhosis induced by thioacetamide (TAA) has been evaluated. Four groups of rats were used: Two of them received 300 mg TAA/l in the drinking water for 3 months while the other two, which served as controls, were given water ad libitum. During the same period and for each one of the treatments, one group received a semi-purified (SP) diet and the other one was fed the same diet supplemented with 1% of the dry residue obtained from R. tomentosus ethanol extract (SP+E). There was a significant reduction of TAA toxicity in rats fed the SP+E diet, as assessed by plasma and liver biochemical markers, and by liver histopathology. Plasma total protein concentration was restored, urea concentration and plasma alkaline phosphatase and gamma-glutamyl-transferase activities were reduced. A significant correction of plasma fatty acids concentrations was also evident. Hepatic alkaline phosphatase and gamma-glutamyl-transferase activities were significantly reduced in animals fed SP+E diet and glucose-6-phosphatase activity was significantly enhanced. The results suggest that R. tomentosus ethanol extract administered in the diet affords protection against TAA-induced cirrhosis, preventing most of the histological changes and functionality alterations own to this experimental pathology.

Breast Cancer Prognosis Determined by Gene Expression Profiling: A Quantitative Reverse Transcriptase Polymerase Chain Reaction Study

Purpose

We sought to reproduce with quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) the results obtained with a 70-gene expression profile that has been described previously in breast cancer.

Patients and Methods

Frozen breast cancer samples from patients who were operated on were used to isolate tumor RNA. Ninety-six patients with stage I to II disease were included. Median age was 57 years (range, 27 to 80 years). Forty-eight patients had lymph node–negative and 48 lymph node–positive disease. qRT-PCR amplifications were performed and the results were correlated with clinical data.

Results

After a minimum follow-up of 5 years, 25 patients had a relapse. The gene profile divided patients into two groups with poor and good prognosis. Significant differences with regard to grade of differentiation, size and hormone receptors were seen between the two groups. The gene profile was significantly associated with relapse-free survival and overall survival in the whole group of 96 patients. Multivariate analysis showed that only lymph node status and gene profile were significantly correlated to overall survival.

Conclusion

qRT-PCR reproduced the results obtained with microarrays for a prognostic gene profile in women with early-stage breast cancer.

Prevalence, resource utilization and costs of vascular dementia compared to Alzheimer's dementia in a population setting

OBJECTIVES

To determine the prevalence of dementia and to measure the monetary impact and health resources utilization of vascular dementia (VD) compared to Alzheimer's dementia (AD) in persons aged over 64 years in a population setting.

METHODS

Retrospective, cross-sectional study. In the initial phase, information was obtained on specific clinical characteristics from the subjects with an active diagnosis of dementia. The second phase consisted of a clinical evaluation and validation of the cases. Mini-Mental State Examination was used to assess cognitive impairment. Dementia and its subtypes were determined using established diagnostic criteria. Information was obtained on the use of health care resources (direct costs) and the number of hours devoted by the primary caregiver (indirect costs) for patients with a documented diagnosis of AD or VD within the last 6 months prior to the interview. A multiple logistic regression analysis was performed to correct the model.

RESULTS

A total of 6,004 subjects were analyzed, 258 with diagnosis of dementia (overall prevalence: 4.3%). An evaluation was made of 224 patients, and gross prevalence of AD and VD was 2.4 and 1.0%, respectively. Cost per patient per semester was EUR 8,086 for AD and EUR 11,039 for VD (p = 0.016). 85.5% of the cost was attributable to primary caregiver time in AD and 84.4% in VD.

CONCLUSIONS

The prevalence of AD and VD increases with age. No sociodemographic differences were seen between AD and VD. Costs associated with health care resource and primary caregiver utilization were high, being higher in VD than in AD.

Differential effect of IL10 and TNF{alpha} genotypes on determining susceptibility to discoid and systemic lupus erythematosus

OBJECTIVE

To ascertain the possible involvement of functional interleukin 10 (IL10) and tumour necrosis alpha (TNFalpha) cytokine promoter polymorphisms on the susceptibility to discoid and systemic lupus erythematosus (DLE, SLE), and their associations with immunological features.

METHODS

Single nucleotide polymorphisms of the IL10 (-1082, -819, and -592) and TNFalpha (-308) genes were determined using allele specific probes in 248 lupus patients and 343 matched controls. To assess functional significance of genotypes, basal mRNA cytokine levels were quantified in 106 genotyped healthy controls by real time RT-PCR. Specific autoantibodies and cutaneous manifestations were analysed in SLE patients and associated with functional genotypes.

RESULTS

After analysing the distribution of IL10 and TNFalpha transcript levels according to promoter genotypes in healthy individuals, patients and controls were classified into functional single and combined genotypes according to the expected high or low constitutive cytokine production. High TNFalpha genotypes (-308AA or AG) were associated with SLE independently of IL10 alleles, whereas the risk of developing DLE and the prevalence of discoid lesion in SLE were higher in the high IL10/low TNFalpha producer group (-1082GG/-308GG). Cytokine interaction also influences the appearance of autoantibodies. Antibodies against Sm are prevalent among low producer patients for both cytokines, a genotype not associated with lupus incidence, whereas low IL10/high TNFalpha patients have the highest frequency of antibodies to SSa and SSb.

CONCLUSIONS

IL10/TNFalpha interaction influences susceptibility to DLE and the appearance of specific autoantibodies in SLE patients, whereas high TNFalpha producer genotypes represent a significant risk factor for SLE.

[Randomized controlled trial comparing a low dose to a conventional dose of hyperbaric bupivacaine for scheduled cesarean section]

INTRODUCTION

Spinal anesthesia is the technique most often applied in cases of scheduled cesarean section. Many authors have tried decreasing the local anesthetic dose by adding opioids to achieve adequate analgesia with greater hemodynamic stability, although the ideal dose remains to be established. Our aim was to analyze hemodynamic stability and quality of analgesia with 2 different regimens for administering spinal hyperbaric bupivacaine.

METHODS

We designed a controlled, double-blind trial comparing 2 doses of spinal hyperbaric bupivacaine with fentanyl in 42 patients undergoing elective cesarean section randomized to 2 groups to receive either the low dose or the conventional one. One group received an 11 mg dose of bupivacaine and the other group received a 6.5 mg dose, combined with 20 microg of fentanyl in both cases.

RESULTS

The hemodynamic profile and the level of maximum sensory block obtained were similar in the two groups. The motor block was less intense in patients receiving the lower dose and it was necessary to convert 2 patients (10%) to general anesthesia in that group.

CONCLUSIONS

Spinal anesthesia with low doses of bupivacaine and fentanyl provides acceptable intraoperative conditions for a high percentage of patients undergoing cesarean section, with a similar incidence of hypotension. The low dose generates a less intense intraoperative motor blockade with similar spread of the sensory block. The low dose was not efficacious for 10% of the patients who received it.

Findings of intravascular ultrasound during acute stent thrombosis

OBJECTIVE

To evaluate the potential role of intravascular ultrasound (IVUS) in evaluating patients experiencing an episode of acute stent thrombosis.

DESIGN AND SETTING

Prospective observational study in a cardiac catheterisation laboratory in a university teaching hospital.

PATIENTS AND INTERVENTIONS

IVUS was used to examine 12 patients undergoing coronary interventions for stent thrombosis to gain further mechanistic insights and to guide treatment. IVUS studies were obtained before and after intervention with a motorised pullback device.

MAIN OUTCOME MEASURES

Qualitative and volumetric IVUS analyses.

RESULTS

Angiographically, 10 patients had occluded vessels and two patients had intraluminal filling defects within the stent. IVUS showed an occlusive thrombus in all patients. Thrombus volume was 90 (77) mm3, which was 51 (21)% of total stent volume. There was evidence of severe stent underexpansion in most patients and no patient fulfilled standard criteria for optimal stent implantation. Stent malapposition was detected in four patients, edge dissections were seen in two patients, and significant inflow-outflow disease was present in 11 patients. During interventions IVUS findings led to the use of higher pressures or larger balloons than those used during initial stenting in 10 patients. In addition, four patients required additional stenting, whereas a thrombectomy device alone was selected for one patient. After the procedure final minimum stent area (7.1 (2.1) v 5.3 (2) mm2, p < 0.005) and stent expansion (83.2 (17) v 62.1 (15)%, p < 0.005) improved compared with pre-interventional values. However, residual lining thrombus was still visualised in eight patients (25 (19) mm3, accounting for a 17% of final stent volume).

CONCLUSIONS

IVUS provides an attractive technique to characterise fully the pattern of stent thrombosis, to identify readily the underlying mechanical predisposing factors, and to guide repeated coronary interventions.

Glucocorticoids up-regulate constitutive interleukin-10 production by human monocytes

BACKGROUND

IL-10 plays an immunosuppressive role in inflammatory responses. Increased plasma levels of IL-10 have been detected in patients under glucocorticoid (GC) therapy, indicating that steroids may exert their suppressive effect, in part, by increasing IL-10 production.

OBJECTIVES

The aim was to define possible mechanisms by which steroids up-regulate IL-10 production. To this end, we have analysed ex vivo the effect of GCs on the constitutive production of IL-10 by lymphocytes and cells of myeloid origin.

METHODS

Monocytes and T cells were isolated by a Percoll gradient and B cells were purified by rosetting. Protein and mRNA IL-10 levels were determined by ELISA and by Northern blot, respectively.

RESULTS

Monocytes, but not T or B cells, up-regulated the constitutive production of IL-10 following pre-treatment for at least 12 h with physiological doses of dexamethasone (Dex). Up-regulation of IL-10 occurred at both protein and mRNA levels, probably indicating that the effect of Dex was by incrementing gene transcription. Other steroids had similar outcomes, their effects being dose-related, proportional to the steroid potency and totally reversed by the steroid antagonist RU486. Thus, transcript levels of IL-10 were up-regulated by GCs probably through binding of the GC receptor to its specific glucocorticoid response element sequence in the IL-10 promoter. In contrast to monocytes, differentiated immature macrophages and dendritic cells did not vary their constitutive IL-10 production after pre-treatment with Dex.

CONCLUSION

Our results support the fact that steroids up-regulate constitutive IL-10 production by selectively triggering activation signals on monocytes.

Surface Pressure–Area Isotherms and Fluorescent Behavior of Phospholipids Containing Labeled Pyrene

In this work, the surface and fluorescent behavior of three phospholipids containing a pyrene molecule in one of their hydrocarbon chains was studied. Differences between the isotherms provided by the different monolayers can be attributed to the orientation of the head group in the phospholipids at the air/water interface. This assertion is supported by the fluorescent behavior of monolayers of phospholipids containing labeled pyrene (Py-DPPE, Py-DPPC, and Py-DPPG).

[Comparison of three genotyping methods for the detection of HIV-1 resistance to antiretroviral drugs]

Highly active antiretroviral therapy has dramatically improved the life expectancy of human immunodeficiency virus (HIV)-infected patients, but mutations in the HIV-1 reverse transcriptase (RT) and protease (P) genes confer drug failure. Evaluation of drug resistance genotyping in HIV-1 has proven to be useful for the selection of drug combinations with maximum antiretroviral activity. The aim of this study was to evaluate the optimal procedure to determine the resistance profile in the laboratory. Plasma from 90 antiretroviral-treated patients was analyzed by reverse hybridization, which identifies the presence of wild-types or mutations at the 19 key codons for protease and RT regions, and was compared with two other methods of direct cDNA sequencing. A total of 408 mutations were detected by InnoLiPA HIV-1, (Line Probe Assay, Innogenetics, Belgium), 572 by TrueGene HIV-1 Genotyping System (Visible Genetics, Canada), and 721 by ViroSeq HIV-1 Genotyping System (Perkin Elmer/Applied Biosystems, California). Hybridization detected a significantly higher number of primary mutations which are associated with a high level of drug resistance (p <0.001). Hybridization also detected a higher number of mixtures of wild-type and mutant viruses. There was a good concordance among the three methods, although it was higher between the two sequencing methods. Sequencing determines a higher number of mutations, but hybridization better identifies primary mutations correlated with a high level of drug resistance. Hybridization is more suitable for detecting mixed populations and is easier to implement in clinical laboratories but does not eliminate the need for sequence analysis for detection of drug-resistant HIV.

Impaired type-1 activity and increased NK cells in Gleich's syndrome

BACKGROUND

An altered production of cytokines has been described in Gleich's syndrome. Our aim was to study the cytokine production at the single-cell level in a patient with Gleich's syndrome and to determine whether it changed during a flare episode.

METHODS

Blood samples were obtained from a 30-year-old woman diagnosed with Gleich's syndrome before and during the subsequent flare of edema of trunk and arms and weight gain. The major lymphoid subsets (CD4+, CD8+, and CD19+) and natural killer (NK) cells were measured by flow cytometry. Cytokine-producing T cells (IL-2, IFN-gamma, and IL-4) were quantified in whole blood by intracellular staining with specific monoclonal antibodies and flow cytometry analysis after polyclonal stimulation with phorbol 12-myristate 13-acetate and ionomycin.

RESULTS

Increased numbers of immature CD4+CD8+ T cells and NK cells were observed in peripheral blood during the asymptomatic period. The latter population significantly decreased during the flare. Type-1 cells were decreased in both asymptomatic and, more markedly, during the attack with respect to healthy subjects.

CONCLUSIONS

The decreased type-1 response demonstrated in this patient might be the basis of the hypereosinophilia of Gleich's syndrome. Besides, the NK cells might play a role in the pathogenesis of these inflammatory episodes.

Period focusing induced by network feedback in populations of noisy integrate-and-fire neurons

The population dynamics of an ensemble of nonleaky integrate-and-fire stochastic neurons is studied. The model selected allows for a detailed analysis of situations where noise plays a dominant role. Simulations in a regime with weak to moderate interactions show that a mechanism of excitatory message interchange among the neurons leads to a decrease in the firing period dispersion of the individual units. The dispersion reduction observed is larger than what would be expected from the decrease in the period. This "period focusing" is explained using a mean-field model. It is a dynamical effect that arises from the progressive decrease of the effective firing threshold as a result of the messages received by each unit from the rest of the population. A back-of-the-envelope formula to calculate this nontrivial dispersion reduction and a simple geometrical description of the effect are also provided.

Paenibacillus jamilae sp. nov., an exopolysaccharide-producing bacterium able to grow in olive-mill wastewater

Endospore-forming strains were isolated from corn-compost treated with olive-mill wastewater ('alpechin'). The strains were taxonomically studied and proposed as a novel Paenibacillus species. These organisms (strains B.3T, B.7 and B.9) were particularly distinguishable from other aerobic spore-forming species by their ability to grow optimally in 100% (v/v) olive-mill wastewater at 30 degrees C and pH 7.0 and concomitant production of an interesting exopolysaccharide. Chemotaxonomic analysis revealed that MK-7 was the predominant menaquinone, the major fatty acid was anteiso C15:0 and the cell wall contained meso-diaminopimelic acid. The DNA G+C content was 40.7 mol%. Comparative sequence analysis of 16S rDNA with different reference species from the genera Bacillus, Paenibacillus, Brevibacillus, Aneurinibacillus, Alicyclobacillus, Halobacillus, Virgibacillus, Amphibacillus, Coprobacillus and Gracilibacillus indicated that the isolated strains were highly related to the genus Paenibacillus. Strain B.3T formed an evolutionary lineage distinct from other species within the evolutionary radiation encompassing the genus Paenibacillus. Strain B.3T was a close relative of Paenibacillus polymyxa, but DNA-DNA relatedness data with this species was very low (relative binding ratio < 16%). Based on the morphological and physiological characteristics, as well as on the phylogenetic position determined by 16S rDNA analysis and DNA-DNA relatedness data, it is concluded that these strains should be designated a novel species, for which the name Paenibacillus jamilae sp. nov. is proposed. The type strain is B.3T (= CECT 5266T = DSM 13815T).

Mono- and dinuclear five-coordinate cyclometalated palladium(II) compounds

Reaction of cyclometalated halide-bridged Pd(II) complexes 1-4 with the tertiary triphosphine ligand (Ph2PCH2CH2)2PPh (triphos) yielded complexes [((Ph2PCH2CH2)2PPh-P,P,P)Pd(N(Cy)=(H)C)C6H2(C(H)=N(Cy))Pd((Ph2PCH2CH2)2PPh-P,P,P)][ClO4]2 5, [Pd(C6H4-N=NC6H5)((Ph2PCH2CH2)2PPh-P,P,P)][ClO4] 6, and [Pd(R-C6H3C(H)=NCy)((Ph2PCH2CH2)2PPh-P,P,P)][ClO4] (7; R = 4-CHO, 8; 3-CHO). Spectroscopic and analytic data suggest five-coordination on the palladium atom, which, for complexes 5, 6, and 7, was confirmed by X-ray crystallography. The geometry around palladium may be view as a distorted trigonal bipyramid, with the palladium, nitrogen, and terminal phosphorus atoms in the equatorial plane. Compound 5 is the first doubly cyclometalated palladium(II) compound with two pentacoordinated metal centers. The structure of 6 comprises two discrete cations with slightly different geometries, showing the importance of crystal packing forces in order to determine the coordination arrangement.

Human papillomavirus-16 E6 variants in cervical squamous intraepithelial lesions from HIV-negative and HIV-positive women

We studied 48 human papillomavirus (HPV)-16-positive squamous intraepithelial lesions (SILs) from HIV-negative patients (16 low-grade SILs [LSILs]; 32 high-grade SILs [HSILs]) and 13 HPV-16-positive SILs from HIV-positive patients with AIDS (1 LSIL; 12 HSILs). After HPV typing, the entire HPV-16 E6 coding region was amplified and sequenced in all samples. We detected 12 HPV-16 E6 prototypes and 4 variants among the LSILs in HIV-negative patients, and 15 HPV-16 E6 prototypes and 17 HPV-16 variants in the HSIL group. The most prevalent variant of SIL types was European 350G, present in 3 and 13 cases, respectively. In 3 HSILs and no LSILs we found mixed infection by an HPV-16 E6 prototype and a variant. Two variants (1 each in LSIL and HSIL) were of non-European lineage. The only LSIL in HIV-positive patients had an HPV-16 E6 prototype; in the HSILs, we found 8 HPV-16 E6-prototypes, 4 with mixed infection with HPV-31 and 4 variants, all European 350G. The higher proportion of HPV-16 E6 variants in HSIL than in LSIL in HIV-negative patients suggests a greater risk of progression. However, further studies are needed.

beta-Catenin expression pattern, beta-catenin gene mutations, and microsatellite instability in endometrioid ovarian carcinomas and synchronous endometrial carcinomas

beta-Catenin gene mutations and microsatellite instability (MI) have been reported in endometrioid ovarian carcinomas. In colon but not endometrial cancer, beta-catenin gene mutations are associated with a replication error phenotype and MI. In this study the authors investigate whether beta-catenin mutations and MI are two independent oncogenic pathways in endometrioid ovarian carcinomas. They also evaluate the usefulness of these molecular markers in determining the primary origin of simultaneous tumors in the ovary and endometrium. This study was performed on 26 patients diagnosed with primary endometrioid ovarian carcinoma, five of whom also had pathologically diagnosed primary synchronous endometrioid endometrial carcinoma. Immunohistochemical and molecular analyses indicated that there were 25 primary ovarian tumors with four primary synchronous endometrial cancers and one ovarian metastasis of a primary endometrial carcinoma. All studies were performed on formalin-fixed, paraffin-embedded tissue samples. The beta-catenin expression pattern (nuclear vs. membranous) was analyzed immunohistochemically. Mutations in exon 3 of the beta-catenin gene were studied by polymerase chain reaction, single-strand conformational polymorphism, and direct sequencing. MI status was established by studying BAT-26 and BAT-25 mononucleotide repeats. In the group with 21 single ovarian tumors, 18 (85%) had beta-catenin nuclear expression, eight (38%) had beta-catenin gene mutations (always associated with beta-catenin nuclear expression), and four (19%) had MI. Only one case (5%) had both beta-catenin gene mutations and MI. The mutations affected one of the serine/threonine residues targeted for phosphorylation by glycogen synthase kinase-3beta or adjacent residues. At codon 32, a GAC-to-TAC (D32Y) change was found; at codon 33, two TCT-to-TGT (S33C) changes were found; at codon 37, three TCT-to-TTT (S37F) changes and one TCT-to-TGT (S37C) change were found; and, lastly, one ACC-to-GCC change at codon 41 (T41A) was detected. Four of the 25 endometrioid ovarian carcinomas (16%) had an associated synchronous endometrial carcinoma. There was a higher percentage of beta-catenin mutations (n = 3, 75%) in synchronous ovarian carcinomas than in single ones, although with a similar percentage of MI (n = 1, 25%). beta-catenin mutations were S37C in two cases and D32G in one. One of the four endometrial carcinomas showed an S33C beta-catenin mutation, and two carcinomas had MI. None of the four tumors had both beta-catenin gene mutation and MI. beta-catenin gene mutations were always associated with a nuclear beta-catenin expression pattern, whereas MI was associated with a membranous pattern. In one patient both the ovarian and the endometrial carcinomas had beta-catenin gene mutations, in another patient both tumors showed MI, whereas in the remaining two patients the ovarian carcinomas showed beta-catenin gene mutations and the endometrial carcinomas showed MI. To summarize, the results of this study suggest that beta-catenin mutations and MI could represent two independent pathways in endometrioid ovarian carcinomas because they occur simultaneously very infrequently (in 5% of these cases). beta-catenin mutations are always associated with a nuclear beta-catenin expression pattern, whereas cases with a replication error -plus phenotype showed no abnormal beta-catenin subcellular localization. The study of the beta-catenin expression pattern, beta-catenin mutations, and MI, together with conventional clinicopathologic findings, could aid in distinguishing between the metastatic or independent origin of simultaneous endometrioid ovarian and endometrial carcinomas. Tumors with identical immunohistochemical and molecular features should therefore be considered to have a common origin.

Expression of factor VII in the liver of patients with liver disease: correlations with the disease severity and impairment in the hemostasis

Factor VII (FVII) plasma levels in patients with liver disease may be below the normal range. However, no data are available on FVII expression in liver biopsies from patients with liver diseases other than cirrhosis. We have analyzed the expression of FVII by in situ hybridization in liver biopsies from 50 patients in comparison with the procoagulant activity of FVII, and with the plasma levels as activated FVII (FVIIa) and FVII antigen. The level of FVIIa was significantly lower in stage 4 liver fibrosis patients than in the remaining ones (P < 0.05). The percentage of hepatocytes expressing FVII was significantly lower in stage 4 liver fibrosis patients (4.1+/-1.3%) than in stage 3 (22.7+/-6.1%), stage 2 (31.5+/-6.1%), stage 1 (43.7+/-8.2%) and stage 0 patients (63.8+/-4.4%) (P < 0.001). These percentages correlated inversely in a statistically significant way with the histological activity index and the liver function tests. We have demonstrated that the FVIIa plasma levels in patients with chronic liver disease other than cirrhosis may be below the normal range in the absence of blood coagulation impairment. The percentage of hepatocytes expressing FVII decreases as the severity of liver damage increases.

Assessment of the risk of fall, related to visual stimulation, in patients with central vestibular disorders

In order to assess the influence of visual stimulation in the triggering of imbalance and falls in the elderly population, the postural responses of 18 elderly patients with central vestibular disorders and clinical evidence of instability and falls were studied while receiving different types of visual stimuli. The stimulation conditions were: (i) no specific stimuli; (ii) smooth pursuit with pure sinusoids of 0.2 Hz as foveal stimulation; and (iii) optokinetic stimulation (OK) as retinal stimuli. Using a platform AMTI Accusway platform, the 95% confidence ellipse (CE) and sway velocity (SV) were evaluated with a scalogram using wavelets in order to assess the relationship between time and frequency in postural control. Velocity histograms were also constructed in order to observe the distribution of velocity values during the recording. A non-homogeneous postural behavior after visual stimulation was found among this population. In five of the patients the OK stimulation generated: (i) significantly higher average values of CE ( > 3.4+/-0.69 cm2); (ii) a significant increase in the average values of the SV ( > 3.89+/-1.15 cm/s) and a velocity histogram with a homogeneous distribution between 0 and 18 cm/s; and (iii) a scalogram with sway frequencies of up to 4 Hz distributed in both the X and Y directions (backwards and forwards and lateral) during visual stimulation with arbitrary units of energy density > 5. These three qualitative and quantitative aspects could be "markers" of visual dependence in the triggering of the mechanism of lack of equilibrium and hence falls in some elderly patients and should be considered in order to prevent falls and also to assist in the rehabilitation program of these patients.

Antihepatotoxic activity of Rosmarinus tomentosus in a model of acute hepatic damage induced by thioacetamide

R. tomentosus is a vegetal species closely related to the culinary rosemary (R. officinalis), a plant reported to contain antihepatotoxic agents. A dried ethanol extract of the aerial parts of Rosmarinus tomentosus (Lamiaceae) and its major fraction separated by column chromatography (fraction F19) were evaluated for antihepatotoxic activity in rats with acute liver damage induced by a single oral dose of thioacetamide. Silymarin was used as a reference antihepatotoxic substance. Pre-treatment with R. tomentosus ethanol extract, fraction F19 or silymarin significantly reduced the impact of thioacetamide toxicity on plasma protein and urea levels as well as on plasma aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and gamma-glutamyl transpeptidase activities compared with thioacetamide-treated animals (group T). Pre-treatment with R. tomentosus ethanol extract significantly reduced the impact of thioacetamide damage on alkaline phosphatase and gamma-glutamyl transpeptidase activities compared with group T. Silymarin administration significantly reduced alkaline phosphatase and gamma-glutamyl transpeptidase activities compared with group T. Fraction F19 administration reduced only alkaline phosphatase activity compared with group T. According to these data, R. tomentosus extract shows promising antihepatotoxic activity, suggesting the need to isolate the chemical principles responsible for this activity and to study this activity in a model of thioacetamide-induced cirrhosis.

Long-term effect of IFNbeta1b treatment on the spontaneous and induced expression of IL-10 and TGFbeta1 in MS patients

Interferon-beta (IFNbeta) is an effective treatment that lessens the frequency and severity of exacerbations in relapsing-remitting multiple sclerosis (RRMS). The mechanism of action of IFNbeta1b may be by upregulating antiinflammatory cytokines levels. We studied the effect of IFNbeta1b treatment on the in vivo gene expression and protein synthesis of two immunosuppressive cytokines, IL-10 and TGFbeta1, and its persistence with chronic therapy. Peripheral blood samples were obtained from 16 patients before and after 3, 6 and 12 months of IFNbeta1b treatment. Eleven patients did not have any clinical relapse, whereas the other five each had one clinical exacerbation during the study. We employed a highly sensitive RT-PCR technique to study the spontaneous gene expression of IL-10 and TGFbeta1. Protein concentration in serum and in culture supernatants from mitogen-stimulated cells were measured by ELISA. In the group of patients who remained clinically stable during the study, IL-10 mRNA levels decreased significantly after 6 months of treatment to normalize at 1 year of therapy as compare with the initial values. In the five patients who relapsed, mRNA IL-10 levels were significantly diminished at 3, 6, and 12 months of therapy. IL-10 serum levels did not vary significantly in any group of patients during the study. Treatment did not modulate mRNA or serum levels of TGFbeta1 at any time period in the group of stable patients. However, in the five patients who relapsed, TGFbeta1 mRNA significantly decreased at 6 and 12 months of therapy. IFNbeta1b treatment was unable to restore the initial low mitogen-induced production of IL-10; only after 1 year of therapy was a slight increase observed. Cytokine therapy did not affect the mitogen-induced production of TGFbeta1. We can conclude that chronic administration of IFNbeta1b does not result in an upregulation of IL-10 and TGFbeta1.

Induction of functional CD154 (CD40 ligand) in neonatal T cells by cAMP-elevating agents

A deficiency of neonatal T lymphocytes to express CD154 antigen in response to ionomycin and phorbol 12-myrsistate 13-acetate (PMA) stimulation or after CD3 cross-linking has been described. In the present report we describe that CD45RA+ newborn cells are able to synthesize and express CD154 at similar or even higher levels than adult cells in response to ionomycin and cAMP-elevating agents which trigger the protein kinase A (PKA) -mediated metabolic pathway. Peak CD154 protein concentrations in newborn cells were found between 4 and 8 hr after stimulation with ionomycin and dibutyryl cAMP. These agents, however, did not induce expression of the early activation antigen CD69. Surface levels of CD154 did not correlate with specific mRNA concentration, indicating that dibutyryl cAMP up-regulates CD154 by acting at a post-transcriptional stage. The CD154 antigen induced by PKA activation of newborn cells was functional, since upon binding to CD40 on B lymphocytes in the presence of interleukin-4 (IL-4), it promoted immunoglobulin heavy-class switching to IgE. We also found a different pattern of cytokine production between neonatal and adult CD4+ T cells. In response to ionomycin and dibutyryl cAMP, cord blood cells were more prone than adult lymphocytes to secrete the T helper type 2-derived immunosuppressive cytokines IL-4 and IL-10. Taking into account that the feto-maternal environment is rich in cAMP-elevating agents, the reduced risk of graft versus host disease associated with cord blood trasplantation, as compared with the risk with adult bone marrow cell transplants, may be due to the bias of neonatal cells to differentiate towards the T helper type 2 functional cell subset.

Hypotensive action of an aqueous extract of Pimenta dioica (Myrtaceae) in rats

The intra-venous (i.v.) hypotensive action of the final aqueous fraction of Pimenta dioica was studied in Spontaneously Hypertensive Rats (SHR). The rats were anaesthetized (sodium pentobarbital 50 mg/kg), the trachea, right carotid artery and jugular vein were cannulated for adequate ventilation, direct blood pressure measurement and intra-venous administration of extracts, solutions and drugs. The arterial line was connected to a pressure transducer (Viggo-Spectramed model P23 XL) and a polygraph (Grass model 7H) and monitored continuously during the first five minutes after plant extract administration and then at 5 and 15 minute intervals for one hour. Responses were taken as the maximum pressure changes observed during this period. Increasing doses of the final aqueous fraction were given i.v. to groups of six SHR each. It produced a dose dependent decrease in blood pressure and the ED50 was 45 mg/kg. To discard that the hypotensive effect of the extracts was due to its ionic composition, a solution containing KCl, NaCl, CaCl2 and MgCl2 equivalent to the ion contents present in a dose of 50 mg/kg of total aqueous extract was injected to Sprague-Dawley rats (SDN) using the same method as described above. It did not produce significant changes in blood pressure. Pharmacological antagonistic studies were done injecting either autonomic ganglion, alpha adrenoceptor, beta adrenoceptor and cholinergic receptor blockers prior to extract administration in SHR rats. Atropine, propranolol and phentolamine did not affect the hypotensive effect of the final aqueous fraction. With hexamethonium (autonomic ganglion blocker) the hypotensive response was diminished in a significant way (p < 0.05). The hypotensive action of the final aqueous extract was not mediated through cholinergic, alpha or beta adrenergic receptors. The extract may posses vasorelaxing activity which could not be evident after autonomic ganglion blockade due to extreme vasodilation present prior to extract administration. Future studies should address the question of a possible direct vasodilating effect of the extracts.