Hepatitis C and liver fibrosis

Chronic hepatitis C progresses to cirrhosis within 20 years in an estimated 20-30% of patients, while running a relatively uneventful course in most others. Certain HCV proteins, such as core and NS5A, can induce derangement of lipid metabolism or alter signal transduction of infected hepatocytes which leads to the production of reactive oxygen radicals and profibrogenic mediators, in particular TGF-beta1. TGF-beta1 is the strongest known inducer of fibrogenesis in the effector cells of hepatic fibrosis, i.e. activated hepatic stellate cells and myofibroblasts. However, fibrogenesis proceeds only when additional profibrogenic stimuli are present, e.g. alcohol exposure, metabolic disorders such as non-alcoholic steatohepatitis, or coinfections with HIV or Schistosoma mansoni that skew the immune response towards a Th2 T cell reaction. Furthermore, profibrogenic polymorphisms in genes that are relevant during fibrogenesis have been disclosed. This knowledge will make it possible to identify those patients who are most likely to progress and who need antiviral or antifibrotic therapies most urgently. However, even the best available treatment, the combination of pegylated interferon and ribavirin, which is costly and fraught with side effects, eradicates HCV in only 50% of patients. While the suggestive antifibrotic effect of interferons (IF-gamma>alpha,beta), irrespective of viral elimination, has to be proven in randomised prospective studies, additional, well tolerated and cost-effective antifibrotic therapies have to be developed. The combination of cytokine strategies, e.g. inhibition of the key profibrogenic mediator TGF-beta, with other potential antifibrotic agents appears promising. Such adjunctive agents could be silymarin, sho-saiko-to, halofuginone, phosphodiesterase inhibitors, and endothelin-A-receptor or angiotensin antagonists. Furthermore, drug targeting to the fibrogenic effector cells appears feasible. Together with the evolving validation of serological markers of hepatic fibrogenesis and fibrolysis an effective and individualised treatment of liver fibrosis is anticipated.

Endothelins and carbon monoxide interact to regulate rat liver microcirculation after haemorrhagic shock

Background

Upregulation of stress-induced vascular mediators such as endothelin (ET) 1, nitric oxide synthase (NOS)–nitric oxide or the haem oxygenase (HO)–carbon monoxide pathway may contribute to altered microvascular responsiveness after ischaemia and reperfusion. A profound induction of HO-1 and an increase in portal resistance after blockade of the HO pathway has been shown to occur after haemorrhagic shock and resuscitation (H/R). This study investigated whether the observed increased portal resistance after blockade of the HO pathway was mediated by a concomitant upregulation of ET-l.

Methods

Sprague–Dawley rats (n = 10 per group) were subjected to H/R (mean arterial pressure 40 mmHg for l h, followed by 5 h of resuscitation). Expression of HO-1, inducible NOS (iNOS) and ET-1 was studied by standard Northern blot analysis and reverse transcriptase–polymerase chain reaction. At 6 h either the ET antagonist bosentan 10 mg kg−1 or vehicle was injected. After 10 min the HO pathway was blocked in all animals by tin protoporphyrin (SnPP) IX 50 μmol kg−1. Subsequently portal flow and portal pressure or sinusoidal liver blood flow (assessed by intravital epifluorescence microscopy) were measured for 30 min.

Results

A profound induction in ET-1 paralleled induced HO-1 messenger RNA (mRNA) gene expression after H/R (ET-1, mean(s.d.) 9·0(1·1)-fold; HO-1, 5·9(0·3)-fold induction at 6 h); iNOS mRNA was below the detection limit. Blockade of the HO pathway led to a significant peak increase in the portal vein resistance (ΔPVR; P < 0·05). There was a trend to a lower peak increase after administration of bosentan (P = 0·07) (ΔPVR: sham SnPP-IX, 0·17(0·05) mmHg min mF−1; shock vehicle SnPP-IX, 0·57(0·15) mmHg min mF−1; shock bosentan SnPP-IX, 0·29(0·05) mmHg min mF−1). Regarding liver microcirculation, pretreatment with bosentan significantly attenuated the observed decrease in perfused sinusoids (PS) and in perfusion index (PI) after blockade of the HO pathway (shock vehicle SnPP-IX: PS 23·1(1·1) mm−1, PI 1000(134) μm3 s−1 mm−1; shock bosentan SnPP-IX: PS 28·8(1·8) mm−1, PI 1483(159) μm3 s−1 mm−1; P < 0·05).

Conclusion

These results suggest a functional interaction of the unregulated vasodilator carbon monoxide and the vasoconstrictor ET-1 at the sinusoidal level in rat liver after H/R.

Modulation of the inflammatory response to cardiopulmonary bypass by dopexamine and epidural anesthesia

BACKGROUND

Cardiopulmonary bypass (CPB) induces a systemic inflammatory reaction. Microcirculation-dependent alteration of the gut mucosal barrier with subsequent translocation of endotoxins is a postulated mechanism for this inflammatory response. This study was designed to elucidate whether two different approaches to modulate splanchnic perfusion may influence systemic inflammation to CPB.

METHODS

We examined 40 patients scheduled for elective coronary bypass surgery in a prospective, randomized study. One group (DPX) received dopexamine (1 micro g. kg-1. min-1) continuously after induction of anesthesia until 18 h after CPB. The control group (CON) received equal volumes of NaCl 0.9% in a time-matched fashion. In a third group (EPI) a continuous epidural infusion of bupivacaine 0.25% [(body height (cm) - 100). 10-1=ml.h-1] was administered for the whole study period. Procalcitonin (PCT), tumor necrosis factor (TNF-alpha), soluble TNF receptor, human soluble intercellular adhesion molecule-1, C-reactive protein (CRP) and leukocyte count were measured as parameters of inflammation.

RESULTS

All parameters significantly increased following CPB. Increases of PCT, TNF-alpha and leukocyte count were significantly attenuated in the DPX and EPI groups at different time points. However, neither splanchnic blood flow nor oxygen delivery and consumption were different when compared with the CON-group.

CONCLUSION

These results do suggest that mechanisms other than an improved splanchnic blood flow by DPX and EPI treatment have to be considered for the anti-inflammatory effects.

Glial cell line-derived neurotrophic factor up-regulates GTP-cyclohydrolase I activity and tetrahydrobiopterin levels in primary dopaminergic neurones

Glial cell line-derived neurotrophic factor (GDNF) protects dopaminergic neurones against toxic and physical damage. In addition, GDNF promotes differentiation and structural integrity of dopaminergic neurones. Here we show that GDNF can support the function of primary dopaminergic neurones by triggering activation of GTP-cyclohydrolase I (GTPCH I), a key enzyme in catecholamine biosynthesis. GDNF stimulation of primary dopaminergic neurones expressing both tyrosine 3-monooxygenase and GTPCH I resulted in a dose-dependent doubling of GTPCH I activity, and a concomitant increase in tetrahydrobiopterin levels whereas tyrosine 3-monooxygenase activity was not altered. Actinomycin D, asan inhibitor of de novo biosynthesis, abolished any GDNF-mediated up-regulation of GTPCH I activity. However, GTPCH I mRNA levels in primary dopaminergic neurones were not altered by GDNF treatment, suggesting that the mode of action for that up-regulation is not directly connected to the regulation of GTPCH I transcription. We conclude that GDNF, in addition to its action in structural differentiation, also promotes differentiation regarding expression and enzymatic activity of a crucial component in the dopaminergic biosynthetic pathway.

Psychiatric reform in Germany

OBJECTIVE

To describe the ongoing process of German psychiatric reform and the structure and functioning of mental health services.

METHOD

Information sources used include official reports describing mental health services, relevant publications related to organization and functioning of services.

RESULTS

There has been far-reaching change in mental health care since the late 1960s: psychiatric hospitals have lost about 50% of their beds and one psychiatric hospital has been closed. One hundred and sixty-five general hospital psychiatric units have been built up. Out-patient, community and residential services have been developed. There is a lack of diversified residential and rehabilitation services, particularly for the most severely ill. Co-ordination of care is not always ensured, transfer of patients to remote nursing homes has occurred in some places. Carers and service users articulate their views to an increasing degree.

CONCLUSION

Political and professional enthusiasm have been important in implementation of the German reform. Evolving it further will require major efforts.

Thyroid hormones, serotonin and mood: of synergy and significance in the adult brain

The use of thyroid hormones as an effective adjunct treatment for affective disorders has been studied over the past three decades and has been confirmed repeatedly. Interaction of the thyroid and monoamine neurotransmitter systems has been suggested as a potential underlying mechanism of action. While catecholamine and thyroid interrelationships have been reviewed in detail, the serotonin system has been relatively neglected. Thus, the goal of this article is to review the literature on the relationships between thyroid hormones and the brain serotonin (5-HT) system, limited to studies in adult humans and adult animals. In humans, neuroendocrine challenge studies in hypothyroid patients have shown a reduced 5-HT responsiveness that is reversible with thyroid replacement therapy. In adult animals with experimentally-induced hypothyroid states, increased 5-HT turnover in the brainstem is consistently reported while decreased cortical 5-HT concentrations and 5-HT2A receptor density are less frequently observed. In the majority of studies, the effects of thyroid hormone administration in animals with experimentally-induced hypothyroid states include an increase in cortical 5-HT concentrations and a desensitization of autoinhibitory 5-HT1A receptors in the raphe area, resulting in disinhibition of cortical and hippocampal 5-HT release. Furthermore, there is some indication that thyroid hormones may increase cortical 5-HT2 receptor sensitivity. In conclusion, there is robust evidence, particularly from animal studies, that the thyroid economy has a modulating impact on the brain serotonin system. Thus it is postulated that one mechanism, among others, through which exogenous thyroid hormones may exert their modulatory effects in affective illness is via an increase in serotonergic neurotransmission, specifically by reducing the sensitivity of 5-HT1A autoreceptors in the raphe area, and by increasing 5-HT2 receptor sensitivity.

[Crystallization and solid state properties of molecules of pharmaceutical interest]

Polymorphism characterizes the ability of a molecule to crystallize in different crystallographic systems (in the case of a simple atom the term allotropy is used). This phenomenon, known for a long time, leads to significantly different physicochemical properties between the different crystalline forms. In the pharmaceutical domain, the potential polymorphism of the active substances and the excipients could affect Since most of the pharmaceutical products consist of solid dosage forms administered by the oral route, it is not surprising that studies on polymorphism have become a mandatory chapter of any pharmaceutical dossier whether it concerns a new chemical entity or a generic. In fact, beyond the polymorphism phenomenon, it is the crystallization process which deserves to be highlighted. We will show how it controls the appearance of the polymorphism and the crystalline growth which is a second feature at least as important as the polymorphism itself (external aspect of the solid particles/habit) in terms of processability and dissolution. After having recalled some thermodynamic considerations which characterize the polymorphism, we will illustrate succinctly the impact of these phenomena on some important aspects of the pharmaceutical development such as the dissolution, the bioavailability and the stability.

Expression of CD44v6 has no prognostic value in patients with colorectal cancer

BACKGROUND AND AIMS

In colorectal cancer patients' mortality is largely influenced by spreading of tumour cells from the primary tumour site and subsequent metastasis formation. CD44 is an adhesion molecule and represents a highly variable family of isoforms. The isoform CD44v6 has been associated with metastatic spread and poor prognosis in animal models and several human cancers. Results of immunohistological studies in primary colorectal cancer are mostly retrospective and contradictory. The aim of our prospective study was to assess the controversial role of CD44v6 as a prognostic factor in colorectal cancer.

METHODS

In 93 patients we analysed tumour CD44v6 expression in prospectively sampled stage I-IV colorectal adenocarcinomas using RT-PCR and Southern blotting. The prognostic value of the CD44v6 expression was assessed using univariate and multivariate analysis.

RESULTS

CD44v6 expression was found in 47 % of the cases. CD44v6 expression failed to show any association with the clinical or histological variables examined. CD44v6 expression did not correlate with survival in long-term follow-up. The most important prognostic factor in this cohort was tumour stage.

CONCLUSIONS

Changes in CD446 expression level do not predict tumour spread or patient survival in colorectal cancer.

Common treatment of polycystic ovarian syndrome and major depressive disorder: case report and review

We present the case of a young woman with treatment-resistant major depression, who presented to the Mood Disorders Clinic with a Hamilton Psychiatric Rating Scale for Depression (HAM-D-21) score of 28, after a year-long treatment with Effexor-XR. The patient also had untreated Polycystic Ovarian Syndrome (PCOS). The resolution of her depressive symptoms resulted from the treatment for PCOS with metformin and spironolactone. The patient remained euthymic 5 months after discontinuation of the antidepressant while continuing therapy for PCOS. We briefly overview of the pertinent literature of the pathophysiology of PCOS and affective disorders, highlighting an overlap in phenotypical presentations between these two disorders. Dysregulation of the hypothalamo-pituitary axis and various end organ systems are implicated in both PCOS and affective disorders. As such, several clinical and biochemical markers are common to both disorders, namely insulin resistance, obesity, and hyperandrogenism. In addition, these metabolic abnormalities are interrelated, causing women with PCOS or affective disorders to get caught in a "vicious cycle" of hormonal dysregulation. The case report presented here illustrates how treatment of symptoms such as insulin resistance and hyperandrogenism can lead to remission of major depressive disorder and PCOS. We suggest that through treatment of underlying metabolic defects, both the mood of the patient and the metabolic condition of PCOS can be assisted.

[Surgery in terminal mitral valve diseases]

In the past few years both the spectrum of mitral valve diseases leading to surgery and the surgical techniques have changed. We present our experience with the preservation of the subvalvular apparatus when mitral valve replacement is performed. In addition to preservation of the subvalvular apparatus of the posterior mitral leaflet, five techniques of subvalvular preservation are described. We conclude that mitral valve replacement should always aim at preservation of the subvalvular structures. The surgical method of choice in cases of isolated mitral valve insufficiency is mitral valve reconstruction. Treatment of associated atrial fibrillation, preferably by radiofrequency ablation, should always be performed concomitantly. Surgery of the mitral valve represents a palliative operation in selected patients with terminal cardiomyopathy.

[Marfan syndrome and heart valve diseases]

Marfan syndrome is a hereditary disease of the connective tissue with increased mortality mostly due to changes of the cardiovascular system. We describe our experience with the surgical treatment of 243 patients with Marfan syndrome and cardiovascular complications. We report the results of treatment of annulo-aortal ectasia using the classical surgical methods of Bentall DeBono and Cabrol and the method for preservation of the native aortic valve and concomitant surgery of the mitral valve. Reconstruction or replacement of the mitral valve is mainly based on the classical indications. Preservation of the native aortic valve and reconstruction of the mitral valve in patients with Marfan syndrome is possible but the long-term results are still unknown.

Pentoxifylline downregulates profibrogenic cytokines and procollagen I expression in rat secondary biliary fibrosis

BACKGROUND

The trisubstituted methylxanthine derivative pentoxifylline inhibits hepatic stellate cell proliferation and collagen synthesis in vitro. The antifibrotic effect of pentoxifylline in a suitable in vivo model of chronic liver fibrogenesis remains to be tested.

METHODS

Groups of adult rats (n=20-23) received oral pentoxifylline at a dose of 8 mg/kg/day from week 1 to week 6, and 16 mg/kg/day from week 1 to week 6 or week 4 to week 6 after complete bile duct occlusion. Animals who underwent sham operation that received 16 mg/kg/day pentoxifylline and untreated rats with bile duct occlusion alone served as controls. After six weeks, animals were sacrificed and parameters of fibrogenesis determined.

RESULTS

Bile duct occlusion caused portal cirrhosis with a 10-fold increased hepatic collagen content in the absence of inflammation or necrosis. This was accompanied by an 11-fold elevated serum aminoterminal procollagen III peptide (PIIINP). The drug induced a dramatic eightfold downregulation of procollagen I mRNA, and suppression of the fibrogenic factors transforming growth factor beta1 and connective tissue growth factor by 60-70%. However, profibrogenic tissue inhibitor of metalloproteinase 1 (TIMP-1) mRNA was increased twofold, resulting in only a moderate decrease in liver collagen, fibrosis score, and PIIINP.

CONCLUSIONS

We conclude that targeting pentoxifylline to the fibrogenic cells, thereby avoiding upregulation of TIMP-1, could become a potent antifibrogenic tool in chronic liver disease.