Long-term evolution of liver histopathology in patients with chronic hepatitis C and sustained response

OBJECTIVE

To evaluate the evolution of histological changes observed in patients with chronic hepatitis C (CHC) and sustained response (SR) compared to non-responders (NR) to antiviral treatment.

METHODS

A retrospective study was performed in a total of 176 patients with CHC. These were divided into two groups: 132 SR and 44 NR. All had undergone a basal liver biopsy prior to treatment onset. A second biopsy was performed in 143 patients, 104 SR and 39 NR. Inflammatory activity and the degree of liver fibrosis was measured by Metavir units (MU). The progression and regression index of fibrosis was calculated before and after treatment. The time elapsed between the two biopsies was 5.9 +/- 0.3 years for SR and 6.6 +/- 0.3 years for NR (NS).

RESULTS

At baseline, 53% of SR patients had mild, chronic active hepatitis (CAH), while this was moderate in 43% of NR patients (p < 0.0001). The time elapsed between baseline and post-treatment liver biopsies was 5.9 +/- 0.3 years for SR subjects and 6.6 +/- 0.4 years for NR subjects (NS). After antiviral treatment 47% of SR subjects presented a normal liver or minimal changes, whilst mild CAH persisted in 34.4% and moderate CAH in 37.5% of NR subjects. Necro-inflammatory activity decreased by 50% in SR subjects and by 15% in NR subjects (p < 0.0001), and fibrosis decreased by 82% in SR subjects (p < 0.0001) and by 66% in NR subjects (p < 0.001). Fibrosis progression index was 0.14 MU/year in SR subjects and 0.21 MU/year in NR subjects (NS). Fibrosis regression index was -0.11 in SR subjects and -0.14 in NR subjects (NS).

CONCLUSIONS

In our series of patients with CHC and SR, we observed histological normalization in approximately fifty per cent of cases during long-term follow-up. NR subjects also showed improvement, especially in the fibrosis score. Both groups showed a marked regression of liver fibrosis after treatment.

Determination of amitrole and urazole in water samples by capillary zone electrophoresis using simultaneous UV and amperometrical detection

In this paper, capillary zone electrophoresis with amperometric detection (CZE-AD) was first applied to the simultaneous separation and determination of amitrole and urazole in water samples. A simple end-column electrochemical detector was used in combination with a commercially available capillary electrophoresis instrument with UV detection. The effects of several important factors were investigated to find optimum conditions. A carbon disk electrode was used as working electrode. Separation and determination of these compounds in water samples were performed in 0.030 mol l(-1) acetate buffers at pH 4.5, 25 kV as separation voltage and the samples were introduced by hydrodynamic mode for 1.5 s. Most of the studies realized showed that the direct electrochemical detection is more sensitive and selective than UV detection. Under the optimum conditions, excellent linearity was observed between peak amperometric signal and analyte concentrations in the range of 0.19-1.35 mg l(-1) for amitrole and 0.20-1.62 mg l(-1) for urazole. The detection limits were 63 and 68 microg l(-1) for amitrole and urazole, respectively. The utility of this method was demonstrated by monitoring water samples, and the assay results were satisfactory. The detection limits using a previous preconcentration step for amitrole and urazole in spiked mineral water samples were 0.6 and 1.0 microg l(-1) for amitrole and urazole, respectively.

Psychometric field study of the new haemophilia quality of life questionnaire for adults: The 'Hemofilia-QoL'

Although there is a worldwide interest in the assessment of health-related quality-of-life (HRQoL) in haemophilia patients, no non-disease specific instruments (for adults) are readily available. In this paper, a haemophilia-specific quality-of-life assessment measure for adults (the Hemofilia-QoL questionnaire) has been developed and tested for psychometric properties in 121 adults with haemophilia living in Spain. The Hemofilia-QoL questionnaire is a self-report modular instrument that assesses nine relevant HRQoL domains for patients with haemophilia (e.g. physical health, daily activities, joint damage, pain, treatment satisfaction, treatment difficulties, emotional functioning, mental health, relationships and social activity). Psychometric examination involved the assessment of data quality, scaling assumptions, reliability (internal consistency and test-retest) and validity (concurrent; external clinical criterion and sensitivity). The Hemofilia-QoL 36-item version questionnaire had acceptable internal consistency and retest reliability values. The questionnaire shows excellent concurrent validity (with the SF-36 Health Survey) and external clinical criterion validity (haemophilia clinical status) and sensitivity (health status changes) as well. The Hemofilia-QoL is now available for adult assessment and is ready for use in clinical research in Spain.

Effects of angiotensin converting enzyme inhibitors in hypertensive patients with aortic valve stenosis: a drug withdrawal study

OBJECTIVE

To determine the effects of angiotensin converting enzyme (ACE) inhibitors in hypertensive patients with aortic valve stenosis (AS).

DESIGN

Observational, drug withdrawal, single blinded study, with randomisation of the order of tests.

SETTING

Hypertension and asymptomatic AS.

PATIENTS AND INTERVENTIONS

20 patients (aged 73 (9) years, valve area 0.7 (0.3) cm2, left ventricular ejection fraction > or = 45%) were enrolled. Each patient underwent two sets of tests (with and without taking the drug), each of which included clinical evaluation, Doppler echocardiogram, and symptom limited exercise echocardiography.

MAIN OUTCOME MEASURES

Functional and haemodynamic variables while taking and not taking ACE inhibitors.

RESULTS

Drug intervention induced no change in patients' subjective functional class. While taking ACE inhibitors, patients had a lower systolic blood pressure (140 (18) mm Hg with ACE inhibitors v 159 (12) mm Hg without ACE inhibitors, p = 0.02), a higher mean pressure gradient (34 (15) mm Hg v 28 (18) mm Hg, p = 0.037), and a higher left ventricular stroke work loss (19 (6)% v 14 (10)%, p = 0.009). Other baseline functional and haemodynamic parameters were unmodified. Five patients had an abnormal blood pressure response during one of the exercise tests (two patients while taking the drug and three patients while not taking the drug). When taking ACE inhibitors, patients had a higher stroke volume at peak stress (59 (11) ml v 54 (25) ml, p = 0.046). All other stress variables remained constant.

CONCLUSIONS

In AS, the afterload relief caused by ACE inhibitors is blunted by a parallel increase in the pressure gradient. However, ACE inhibitors favourably affect stress haemodynamic function in most hypertensive patients with AS and should not be discontinued.

Long-term behavioural and neuroendocrine effects of perinatal activation or blockade of CB1 cannabinoid receptors

The present work studied the long-term effects of chronic perinatal manipulation of cannabinoid CB1 receptors in male and female rats. Perinatal activation of cannabinoid CB1 receptors by chronic administration of delta9-tetrahydrocannabinol at different doses (0.1, 0.5, 2 mg/kg, p.o.) induced sexually dimorphic behavioural changes in adulthood, altering habituation of locomotion, immobility and exploratory activity. These behavioural effects were also accompanied by alterations in corticosterone levels in the adult period. Prenatal blockade of CB1 receptors by chronic administration of 3 mg/kg (s.c.) of SR141716A decreased immobility behaviour in male and female animals, without any significant changes in corticosterone plasma levels. Cannabinoid CB1 receptors appear to play an important role in the ontogeny of psychomotor behaviours, and activation or blockade of these receptors during stages of plasticity, such as the prenatal or perinatal periods, can induce long-term effects, as shown by sexually dimorphic changes in behavioural patterns in adulthood.

Behavioural effects of quinpirole following withdrawal of chronic treatment with the CB1 agonist, HU-210, in rats

The present study investigated spontaneous and quinpirole-induced motor responses of in rats, following withdrawal from chronic treatment with the potent cannabinoid agonist HU-210. Withdrawal from chronic HU-210 (20 microg/kg daily, 14 days) produced a decrease in spontaneous activity at 1 and 2 days and enhanced the hyperactivity induced by acute administration of the dopamine D2 agonist quinpirole (0.5 mg/kg) at 4 days after the end of HU-210 treatment. Administration of quinpirole on day 4 of withdrawal from chronic HU-210 enhanced stereotyped responses and induced jumping behaviour. These results suggest that withdrawal from chronic exposure to cannabinoid agonists could induce a time-dependent alteration in dopamine D2 psychomotor function, leading to a behavioural disorganization, comparable to acute psychotic episodes after continuous cannabinoids.

Antennal phenotype of Triatoma dimidiata populations and its relationship with species of phyllosoma and protracta complexes

Triatoma dimidiata (Latreille 1811) Reduviidae Triatominae is the main vector of Chagas disease in several countries of Latin America. As for other vector species, the characterization of T. dimidiata subpopulations within particular geographical regions or occupying different habitats could help in better planning of vector control actions. A first objective in this study was to evaluate the antennal phenotype as a phenetic marker to characterize populations of T. dimidiata collected in different geographic areas and domestic and sylvatic habitats. A second objective was to evaluate the phenetic relationships of T. dimidiata with other species of the phyllosoma complex: longipennis, pallidipennis, and phyllosoma. The antennal sensilla of T. dimidiata specimens collected in Mexico, Central America, and Colombia were analyzed and compared with the antennal sensilla of T. longipennis, T. pallidipennis, and T. phyllosoma. T. barberi was used as an outgroup in the analysis. For each specimen, the ventral side of the three distal segments of the antennae was drawn, identifying and counting four types of sensilla. In T. dimidiata, univariate and multivariate analysis showed differences between sexes, among populations collected in different habitats within the same region, and among populations collected in different geographic regions. Two types of antennal sensilla showed a latitudinal variation. Domestic specimens showed intermediate characteristics of the antennal phenotype, between sylvatic cave- and sylvatic forest-collected specimens. The antennal phenotypes show high similarities among T. pallidipennis, T. phyllosoma, and T. longipennis, with a better differentiation of T. pallidipennis. T. dimidiata is separated from the other members of the complex by a similar distance to T. barberi, of the protracta complex.

Fungal communities in PAH-impacted sediments of Genoa-Voltri Harbour (NW Mediterranean, Italy)

Organic matter (in terms of carbohydrates and proteins), polycyclic aromatic hydrocarbons (PAHs) and bacterial density were investigated in the sediments of three stations in Genoa-Voltri Harbour (NW Mediterranean), and related to the sedimentary fungal community. Sites were significantly different in all investigated parameters (ANOVA, p<0.05), and a sharp gradient of impact in the area was found. All the 81 strains of filamentous fungi isolated, belonging to 7 genera, appeared to be linked with PAHs (p<0.05; r=0.95), whereas bacterial density was positively correlated with organic matter content (p<0.05; r=0.98). Within the fungal community, strains with a high capability to degrade xenobiotics were found. Among the genera identified, Penicillium, Mucor and Cladosporium showed the highest frequency in the sites where the heaviest concentrations of PAHs were recorded. This study suggests that fungal communities are important for in situ degradation of xenobiotics in impacted sediments.

Polarization of valence band holes in the (Ga,Mn)as diluted magnetic semiconductor

We report on direct measurements of the impurity band hole polarization in the diluted magnetic semiconductor (Ga,Mn)As. The polarization of impurity band holes in a magnetic field is strongly enhanced by antiferromagnetic exchange interaction with Mn ions. The temperature dependence of the hole polarization shows a strong increase of this polarization below the Curie temperature. We show that the ground state of the impurity band is formed by uniaxial stress split F=+/-1 states of antiferromagnetically coupled Mn ions (S=5/2) and valence band holes (J=3/2). The gap between the Mn acceptor related impurity band and the valence band is directly measured in a wide range of Mn content.

Retreatment and maintenance therapy with infliximab in fistulizing Crohn's disease

OBJECTIVES

Infliximab has clearly demonstrated its efficacy in the short-term treatment of fistulizing Crohn's disease. We present here the results of retreatment and long-term maintenance therapy.

PATIENTS AND METHODS

Eighty one consecutive patients with active fistulizing Crohn's disease, in whom previous treatments had failed, were treated with infliximab. All patients received as the initial treatment of 5 mg/kg i.v. infusions (weeks 0, 2, and 6). Those patients who failed to respond after the initial cycle (group 1, n = 25), or those who relapsed after having responded (group 2, n = 13), received retreatment with three similar doses (weeks 0,2, and 6). Those who responded to retreatment were included in a long-term maintenance programme (n = 44), with repeated doses (5 mg/kg i.v. infusions) every eight weeks for 1-2 years.

RESULTS

In the initial treatment 56% of the patients responded partially; this response being complete in 44%. In the retreatment, 28% of group 1 (non-responders) presented a complete response, compared to 77% in group 2 (relapsers) (p < 0.0001). In the maintenance treatment, the global response was 88% (39/44). The mean number of doses per patient was 4.4 +/- 2 (range 1-9) with a duration of 36 +/- 12 weeks (range 8-72). Adverse effects were not significantly increased in either treatment.

CONCLUSIONS

Both retreatment and long-term maintenance therapy with infliximab, are highly effective and well tolerated in fistulizing Crohn's disease patients.

Thyroid-hormone effects on putative biochemical pathways involved in UCP3 activation in rat skeletal muscle mitochondria

In vitro, uncoupling protein 3 (UCP3)-mediated uncoupling requires cofactors [e.g., superoxides, coenzyme Q (CoQ) and fatty acids (FA)] or their derivatives, but it is not yet clear whether or how such activators interact with each other under given physiological or pathophysiological conditions. Since triiodothyronine (T3) stimulates lipid metabolism, UCP3 expression and mitochondrial uncoupling, we examined its effects on some biochemical pathways that may underlie UCP3-mediated uncoupling. T3-treated rats (Hyper) showed increased mitochondrial lipid-oxidation rates, increased expression and activity of enzymes involved in lipid handling and increased mitochondrial superoxide production and CoQ levels. Despite the higher mitochondrial superoxide production in Hyper, euthyroid and hyperthyroid mitochondria showed no differences in proton-conductance when FA were chelated by bovine serum albumin. However, mitochondria from Hyper showed a palmitoyl-carnitine-induced and GDP-inhibited increased proton-conductance in the presence of carboxyatractylate. We suggest that T3 stimulates the UCP3 activity in vivo by affecting the complex network of biochemical pathways underlying the UCP3 activation.

Chagas' disease susceptibility/resistance: linkage disequilibrium analysis suggests epistasis between major histocompatibility complex and interleukin-10

Association between the major histocompatibility complex (MHC) and the susceptibility/resistance to acquire Chagas' disease has been largely demonstrated. To study the role of candidate genes in this susceptibility/resistance to Chagas, we designed a population-genetic-based case-control approach (chagasic n = 104 and controls n = 60) and tested the presence of genotype and linkage disequilibrium on microsatellite loci establishing specific landmarks for the MHC, interleukin (IL)-2, IL-2Rbeta chain, IL-4, IL-10, and natural resistance-associated mactophage protein 1 (NRAMP1). After demonstrating no genetic stratification among cases and controls (F(st) were not different from 0), we found significant allelic differences among chagasic patients and controls at microsatellite locus D6S291 (MHC) and at the microsatellite pointing out the IL-10. At the MHC, we found significant differences between patients and controls in Hardy-Weinberg equilibrium-expected genotype proportions. Additionally, MHC II-locus-inferred haplotypes in chagasic patients exhibited strong significant departures from the expected proportions predicted by the second Mendelian law. The linkage disequilibrium pattern at MHC involves a region of approximately 10 cM. These results replicate previous analyses and suggest that presence of epistasis between MHC with humoral systems, such as IL-10, could be underlying the susceptibility/resistance to Chagas' disease.

Impurities in noncubic crystals: stabilization mechanisms for Jahn-Teller ions in layered perovskites

Mechanisms responsible for the local geometry around Jahn-Teller impurities in K2NiF4 type lattices are shown to be different from those generating the warping in cubic crystals. The present density functional theory calculations reveal that the elastic anisotropy of the host lattice (visible for closed shell impurities) and the electric field created by the rest of lattice ions upon active electrons make it possible to have d(9) ions in an elongated geometry but with a A(1g) ground state. The puzzling difference between equilibrium geometries for Cu2+ and Ni+ in layered perovskites can reasonably be understood.

Compliance matching stent placement in the carotid artery of the swine promotes optimal blood flow and attenuates restenosis

OBJECTIVES

We assessed the value of a gradient-compliant stent in an animal model.

METHODS

Bilateral carotid arteries were stented with nitinol stents having variable-oversizing, variable-stiffness, and with (CMS, 10 animals) and without (SMART, four animals) compliance-matching endings. Angiography, hemodynamic, scanning-electron-microscopic and histological analyses were performed at 3-month. The protocol was completed in 14 among 19 swines.

RESULTS

Transient (1-month) exaggerated recoil, attributable to stress-induced phasic inhibition of vasorelaxation, developed at CMS endings. At mid-term, all stents were endothelialized; CMS-stents, but not SMART-stents, were incorporated into walls (one-strut-thickness). Restenosis developed outside SMART-stents (cell migration+wall-compensatory enlargement) whereas CMS-stents elicited no or focalized cell-accumulations at endings that bulged vascular walls radially outward. SMART-stents were blood-flow neutral, whereas CMS-stents favored (higher-stiffness, higher-oversizing) or opposed (lower-stiffness, less-oversizing) carotid blood flow.

CONCLUSIONS

Direct carotid stenting with stents having compliance-matched endings and specific requirements of stiffness and oversizing can optimize blood flow to the brain and restrict local restenosis.

Nanomechanics of the formation of DNA self-assembled monolayers and hybridization on microcantilevers

Biomolecular interactions over the surface of a microcantilever can produce its bending motion via changes of the surface stress, which is referred to nanomechanical response. Here, we have studied the interaction forces responsible for the bending motion during the formation of a self-assembled monolayer of thiolated 27-mer single-stranded DNA on the gold-coated side of a microcantilever and during the subsequent hybridization with the complementary nucleic acid. The immobilization of the single-stranded DNA probe gives a mean surface stress of 25 mN/m and a mean bending of 23 nm for microcantilevers with a length and thickness of about 200 microm and 0.8 microm, respectively. The hybridization with the complementary sequence could not be inferred from the nanomechanical response. The nanomechanical response was compared with data from well-established techniques such as surface plasmon resonance and radiolabeling, to determine the surface coverage and study the intermolecular forces between neighboring DNA molecules anchored to the microcantilever surface. From both techniques, an immobilization surface density of 3 x 10(12) molecules/cm(2) and a hybridization efficiency of 40% were determined. More importantly, label-free hybridization was clearly detected in the same conditions with a conventional sensor based on surface plasmon resonance. The results imply that the nanomechanical signal during the immobilization process arises mainly from the covalent attachment to the gold surface, and the interchain interactions between neighboring DNA molecules are weak, producing an undetectable surface stress. We conclude that detection of nucleic acid hybridization with nanomechanical sensors requires reference cantilevers to remove nonspecific signals, more sensitive microcantilever geometries, and immobilization chemistries specially addressed to enhance the surface stress variations.

Thermal AFM: a thermopile case study

In this work, an atomic force microscope (AFM) with an integrated thermal sensor has been used to obtain the local spatial distribution of temperatures in a micromachined thermopile with submicron resolution. In this communication, we will show how the dimensional, structural and functional characteristics of a thermopile suits well with the requirements for AFM thermal imaging, and how a deeper insight of the thermopile operation can be gained with the aid of these advanced scanning probe-based tools.

A population-based study on the incidence of inflammatory bowel disease in Oviedo (Northern Spain)

OBJECTIVE

to assess the incidence of inflammatory bowel disease in Oviedo (Northern Spain), and to describe the clinical features of new patients.

PATIENTS AND METHODS

a prospective population-based study was made at the Health Area IV, Principality of Asturias (Oviedo, 312,324 inhabitants). All new diagnosed patients with inflammatory bowel disease were registered over a 2-year period.

RESULTS

a total of 85 patients were included, 47 of these with ulcerative colitis (UC), 37 with Crohńs disease (CD), and 1 with undetermined colitis. The overall adjusted incidence rate of UC and CD per 105 inhabitants between 15-64 years was 9.1 (95% CI: 5-13.1) and 7.5 (95% CI: 3.8-11.2), respectively. The global male/female ratio was 0.9, without significant differences between both diseases. CD patients were younger than those with UC (33 +/- 15 years vs 45 +/- 20 years; p < 0.05). Mostly, CD patients were diagnosed at an age younger than 35 years (65%), while UC patients were diagnosed at an age between 25 and 64 years (81%). Disease extension in UC was proctitis in 11%, left-side colitis in 53% and extensive colitis in 36%. With respect to CD, the ileo-colonic form predominated (49%), followed by the ileal (40%) and colonic (11%) forms; an inflammatory, stenotic and fistulous pattern was seen in 54, 22 and 24% of patients, respectively.

CONCLUSIONS

in our area, the incidence of CD is similar to that in other Northern European countries, while UC has a lower incidence. CD mainly affects young people, while UC predominates in middle-aged patients. At diagnosis, UC is predominantly localized, the ileo-colonic form and an inflammatory pattern being most frequent in CD patients.

Development of a new disease-specific quality-of-life questionnaire to adults living with haemophilia

A haemophilia-specific health-related quality-of-life questionnaire (named 'Hemofilia-QoL') was developed to assess quality-of-life in adults with haemophilia, and was psychometrically tested. Seventy-three interviews with haemophilia patients and health care professionals were used to generate the items included in the questionnaire, and expert ratings on the items formulated were used to screen them for potential omission. This was followed by psychometric testing in a sample of 35 patients. Preliminary psychometric testing of the revised questionnaire version, which contains 10 domains (physical health, physical role, joint damage, pain, treatment satisfaction, emotional role, mental health, social support), showed acceptable reliability (alpha = 0.94 for the Hemofilia-QoL total score) and validity, and this will be examined in a subsequent study with a larger patient sample.

Local and systemic immune responses to Echinococcus granulosus in experimentally infected dogs

Local and systemic immune responses were studied in six dogs experimentally infected with the dog/sheep tapeworm Echinococcus granulosus. All dogs developed similar IgG antibody response to parasite antigens. In contrast, IgE and IgA responses differed widely. No relationship between IgA responses and parasite burden at the end of the infection were observed. Further, clear differences in the anti-parasite IgA response in serum as compared with specific IgA forming cells in mesenteric lymph nodes were observed within the same dog. An inverse association of anti-parasite IgE and parasite load seemed to be present, with the strongest IgE response in the one dog that had no worms in the intestine at the end of the experiment. No differences were observed in the numbers of intestinal mast cells and goblet cells among all infected dogs. However, the dog with no detectable parasite load had a marked reduction of detected mast cells in the submuscular and muscular layer of the mucosa. Our data give new insight into the immune response of dogs during E. granulosus infection and provide information that may be useful for the rational design of vaccines for the control of hydatid disease.

Comparison of the performance of the Gea extracorporeal knot with the Roeder extracorporeal knot and the classical knot

BACKGROUND

Laparoscopy is useful to treat surgical diseases, yet tying sutures in the cavity is a challenge. A knot to secure tissue approximation, which would be hand-made, secure, simple, easy, quick, reliable, and extracorporeal without extra mechanical devices, was developed and named the Gea knot.

METHODS

A comparative study of the Gea knot, the Roeder knot, and the classical surgical knot, as the gold standard, using polypropylene, silk, catgut, polyglycolic acid, and Polyglactin 910, all of them of 1-0 caliber, was performed in pigs. Measurements were time to perform, slippage, and breaking point which was measured with a manual digital tensiometer.

RESULTS

The Gea knot was significantly faster statistically to perform than the Roeder knot and more resistant against rupture and slippage. The slippage rate was significantly lower statistically in the Gea knot than in the Roeder knot when Polyglactin 910 and polypropylene were used.

CONCLUSION

The Gea knot is a good alternative for laparoscopic procedures.