Hepatocyte destruction with enhanced collagen synthesis: characteristic feature of chronic hepatitis C patients on haemodialysis

Hepatitis C virus (HCV) infection is frequent among patients with end-stage renal disease on haemodialysis and is considered to be an independent risk factor for mortality in this setting. However, only a few of these patients are treated with anti-hepatitis virus treatment before the development of end-stage renal disease. Recent guidelines recommend identification of patients with good prognoses who are in need of interferon treatment, but we know little of patients who must be treated urgently. Ninety-eight patients on haemodialysis (48 anti-HCV-positive and 50 anti-HCV-negative patients) were enrolled in this study; HCV RNA was detected in 43 anti-HCV-positive patients. Univariate analysis and multivariate regression analysis were applied to identify variables independently associated with persistent HCV infection. Seven variables were proven to be associated with persistent HCV infection. Among them, type IV collagen 7S and N-terminal propeptide of type III procollagen (P-III-P) were defined as independent variables useful in distinguishing HCV RNA-positive patients from HCV RNA-negative patients with 0.91 sensitivity, 0.91 specificity, 0.89 positive predictive value and 0.93 negative predictive value. Our observations suggest that hepatocyte destruction with enhanced liver fibrosis is a characteristic clinical feature of persistent HCV infection. Type IV collagen 7S of ≥ 5 ng/mL and/or P-III-P of ≥ 5 U/mL would be useful markers to identify patients in need of interferon treatment, which supports the idea of the Kidney Disease: Improving Global Outcomes guidelines that a good prognosis in patients with HCV infection on haemodialysis should prompt consideration for IFN treatment when applicable.

Toll-like receptor 2-mediated modulation of growth and functions of regulatory T cells by oral streptococci

This study was designed to determine whether oral streptococci modulate the growth and functions of regulatory T cells. Heat-killed cells of wild-type strains of Streptococcus gordonii and Streptococcus mutans induced the Toll-like receptor 2 (TLR2) -mediated nuclear factor-κB (NF-κB) activation, but their lipoprotein-deficient strains did not. Stimulation with these streptococci resulted in a significant increase in the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in splenocytes derived from both TLR2(+/+) and TLR2(-/-) mice, but the level of increase in TLR2(+/+) splenocytes was stronger than that in TLR2(-/-) splenocytes. Both strains of S. gordonii enhanced the proliferation of CD4(+) CD25(+) Foxp3(+) regulatory T cells isolated from TLR2(+/+) mice at the same level as those from TLR2(-/-) mice in an interleukin-2-independent manner. However, wild-type and lipoprotein-deficient strains of both streptococci did not enhance the suppressive activity of the isolated regulatory T cells in vitro, but rather inhibited it. TLR ligands also inhibited the suppressive activity of the regulatory T cells. Inhibition of the suppressive activity was recovered by the addition of anti-IL-6 antibody. Pretreatment of antigen-presenting cells with the NF-κB inhibitor BAY11-7082 enhanced the suppressive activity of the regulatory T cells. These results suggested that interleukin-6 produced by antigen-presenting cells inhibits the suppressive activity of the regulatory T cells. Wild-type strain, but not lipoprotein-deficient strain, of S. gordonii reduced the frequency of CD4(+)  CD25(+)  Foxp3(+) regulatory T cells in the acute infection model, whereas both strains of S. gordonii increased it in the chronic infection model mice. Hence, this study suggests that oral streptococci are capable of modulating the growth and functions of regulatory T cells in vitro and in vivo.

Hindlimb suspension does not influence mechanical sensitivity, epidermal thickness, and peripheral nerve density in the glabrous skin of the rat hind paw

Our aim was to investigate the influence of microgravity on the sensitivity of the skin to mechanical stimulation, epidermal thickness, peripheral nerve density in the upper dermis, and serum levels of a stress marker in a rat hindlimb suspension (HS) model. Thirty 8-week-old male Wistar rats were randomly divided into 3 groups: HS, n=10; sham HS, n=10; control, n=10. The suspension system was attached to rat tails in both the HS and sham-HS groups, but the hindlimbs were suspended only in the HS group. The HS and sham-HS groups were treated for 4 weeks. In behavioral tests using von-Frey filaments (n=5 in each group), mechanical hypersensitivity developed in the HS and sham HS groups. Serum corticosterone levels increased significantly in the HS and sham HS groups compared to the control group, and no changes in epidermal thickness or peripheral nerve density were observed immediately after the removal of HS (n=5 in each group). These data indicated that the mechanical hypersensitivity observed in the HS group was not caused by microgravity or inactivity, but rather by restraint stress. We suggest that microgravity does not affect skin sensitivity and histology in these animals. Unit of Physical Therapy and Occupational Therapy Sciences, Nagasaki University Graduate School of Biochemical Sciences, Nagasaki-shi, Japan.

Modulation of fibronectin synthesis by cancer cell-fibroblast interaction

Conditioned medium (CM) of human rectal adenocarcinoma cell line RCM-1 stimulated both cellular (c-) and plasma (p-) fibronectin (FN) production by human fibroblasts and modulated the alternative splicing of its primary transcript at the EDA region to express more EDA-containing (+) mRNA. This EDA(+) mRNA-stimulating effect of CM was inhibited by treatment with an anti-human transforming growth factor (TGF)-beta antibody. TGF-beta production by RCM-1 cells was demonstrated by immunoblotting and RT-PCR. Thus, FN synthesis and splicing-in at the EDA region in fibroblasts were stimulated by cancer cells predominantly via TGF-beta. Since RCM-1 cells adhered to cFN, which contains EDA, more efficiently than pFN and adhesion to extracellular matrix proteins such as FN is the first step to migration, the cancer stroma modulated by cancer cell-fibroblast interaction may facilitate cancer invasion.

Effects of transglucosidase on diabetes, cardiovascular risk factors and hepatic biomarkers in patients with type 2 diabetes: a 12-week, randomized, double-blind, placebo-controlled trial

In this 12-week, randomized, double-blind, placebo-controlled trial, the efficacy and safety of transglucosidase (TGD) were compared with placebo in patients with type 2 diabetes mellitus (T2DM). At 12 weeks, TGD 300 mg/day and TGD 900 mg/day significantly reduced HbA1c (0.18 and 0.21%) and insulin concentration (19.4 and 25.0 pmol/l), respectively, vs. placebo. TGD 300 mg/day and TGD 900 mg/day also significantly reduced low-density lipoprotein cholesterol (0.22 and 0.17 mmol/l, respectively). TGD 900 mg/day significantly reduced triglyceride by 0.24 mmol/l and diastolic blood pressure by 8 mmHg. Placebo was associated with a significant increase from baseline in body mass index, alanine aminotransferase and aspartate aminotransferase (0.17 kg/m(2) , 3 and 2 U/l, respectively), whereas TGD was not. TGD 300 mg/day significantly increased high-molecular-weight adiponectin by 0.6 µg/ml. Adverse events did not differ significantly between the groups. TGD resulted in lowering of HbA1c and blood insulin level and improvements in metabolic and cardiovascular risk factors in T2DM.

PGE(2) -EP(2) signalling in endothelium is activated by haemodynamic stress and induces cerebral aneurysm through an amplifying loop via NF-κB

BACKGROUND AND PURPOSE

Cerebral aneurysm is a frequent cerebrovascular event and a major cause of fatal subarachnoid haemorrhage, but there is no medical treatment for this condition. Haemodynamic stress and, recently, chronic inflammation have been proposed as major causes of cerebral aneurysm. Nevertheless, links between haemodynamic stress and chronic inflammation remain ill-defined, and to clarify such links, we evaluated the effects of prostaglandin E(2) (PGE(2) ), a mediator of inflammation, on the formation of cerebral aneurysms.

EXPERIMENTAL APPROACH

Expression of COX and prostaglandin E synthase (PGES) and PGE receptors were examined in human and rodent cerebral aneurysm. The incidence, size and inflammation of cerebral aneurysms were evaluated in rats treated with COX-2 inhibitors and mice lacking each prostaglandin receptor. Effects of shear stress and PGE receptor signalling on expression of pro-inflammatory molecules were studied in primary cultures of human endothelial cells (ECs).

KEY RESULTS

COX-2, microsomal PGES-1 and prostaglandin E receptor 2 (EP(2) ) were induced in ECs in the walls of cerebral aneurysms. Shear stress applied to primary ECs induced COX-2 and EP(2) . Inhibition or loss of COX-2 or EP(2) in vivo attenuated each other's expression, suppressed nuclear factor κB (NF-κB)-mediated chronic inflammation and reduced incidence of cerebral aneurysm. EP(2) stimulation in primary ECs induced NF-κB activation and expression of the chemokine (C-C motif) ligand 2, essential for cerebral aneurysm.

CONCLUSIONS AND IMPLICATIONS

These results suggest that shear stress activated PGE(2) -EP(2) pathway in ECs and amplified chronic inflammation via NF-κB. We propose EP(2) as a therapeutic target in cerebral aneurysm.

Acid inhibits TRPV4-mediated Ca²⁺ influx in mouse esophageal epithelial cells

BACKGROUND

The transient receptor potential vanilloid 4 (TRPV4), a thermo-sensitive stretch-activated cation channel, is expressed in the skin stratified squamous epithelium, contributing to the acquisition of barrier function. Similarly, functional TRPV4 may be located in the stratified squamous epithelial lining of the esophagus, being involved in the pathogenesis of gastroesophageal reflux disease (GERD). Here we investigated the expression of TRPV4 in the mouse esophageal epithelium.

METHODS

TRPV4 expression at the mRNA and protein levels was examined by reverse transcription-polymerase chain reaction (RT-PCR), in situ hybridization, and immunohistochemistry. A calcium imaging technique and ATP assay were used to evaluate the functionality of TRPV4 in freshly isolated esophageal epithelial cells.

KEY RESULTS

Transcripts and proteins encoding TRPV4 were colocalized in the basal and intermediate layers of the esophageal epithelium. Both 4α-phorbol 12,13- didecanoate (4α-PDD), a selective agonist for TRPV4, and hypo-osmolar solution (160 mOsm) elevated the intracellular calcium concentration ([Ca(2+) ](i) ) in a subset of the isolated cells (70%). These [Ca(2+) ](i) increases were potently inhibited by ruthenium red (RuR), a TRPV4 channel antagonist, and were suppressed by extracellular protons (pH 5.0). Finally, application of 4α-PDD evoked ATP release in primary esophageal epithelial cells.

CONCLUSIONS & INFERENCES

Acid-sensitive TRPV4 channels were mainly expressed in the esophageal epithelial cells of the basal and intermediate layers. Direct exposure of TRPV4-expressing cells to gastric acid, as would occur in cases of GERD, could influence their cellular functions, possibly aggravating the disease state.

The short-term role of corticosteroid therapy for pulmonary arterial hypertension associated with connective tissue diseases: report of five cases and a literature review

Pulmonary arterial hypertension (PAH) is a life-threatening complication in connective tissue diseases (CTD). It remains controversial whether immunosuppressive therapy is useful for PAH associated with CTD (PAH-CTD). The Dana Point algorithm does not refer such treatments in patients with PAH-CTD due to the lack of evidence. However, some case reports have shown the potential efficacy of immunosuppression for PAH-CTD. Here we report five cases of PAH-CTD treated with corticosteroids and discuss the current management of PAH-CTD with immunosuppressive agents. Our cases consisted of three active systemic lupus erythematosus (SLE), a quiescent SLE and an active polymyositis. WHO functional classes at baseline were class III in three cases and class II in two. Median follow-up period was 44 (28-92) weeks. PAH was diagnosed by right heart catheterization in all cases (median pulmonary arterial pressure was 45 (29-49) mmHg). All patients received 1 mg/kg of prednisolone (PSL) for 2-4 weeks, followed by appropriate dose reduction. Methylprednisolone pulse therapy was performed in patients resistant to the high dosage of PSL. Four patients received vasodilators in combination. The therapy as above improved WHO functional class 4 weeks after the initiation of PSL in all the patients. Two patients required dose increase or additional administration of vasodilators due to the dose reduction of PSL. Corticosteroid therapy may be effective for PAH-CTD at least in the short term, even in low general activity of CTD or moderate PAH. Our experience suggests that corticosteroid therapy, by itself or in conjunction with standard vasodilators, is effective for PAH-CTD patients.

[Clinical managements for intractable pneumothorax with interstitial pneumonia]

Intractable pneumothorax with interstitial pneumonia (IP) is famous for the disease finally to lead to death in case of persistent air leakage. It is because severe infection, respiratory insufficiency and tissue healing insufficiency by treatments with steroid hormones and immune-suppressants on IP. Pleurodesis is generally performed although the effect of it is questionable. It is important to stop immune-suppressants and reduce steroid hormones before the treatments to succeed in thoracoscopic surgery and thoracographic fibrin glue sealing method (TGF) if possible. Less invasive interventional treatments like TGF are recommendable because intractable pneumothorax with IP is in the high risk group to need to avoid surgery. Hand suturing, looping, covering and putting TachoComb on the air leak point instead of end-stapling should be performed in order to stop air leakage when forced to choose thoracoscopic surgery.

A Case of Orthostatic Tachycardia Syndrome Presenting with Panic Attack during Tilt Table Testing

A 26-year-old woman experienced syncope on standing 2–3 times a year for more than 15 years. The attack was typically associated with palpitations and frequently accompanied by a feeling of intense fear. The patient underwent head-up tilt table testing at 70°for 40 min to determine the cause of the syncope. The tilt test results suggested that the etiology of the syncope was orthostatic tachycardia syndrome complicated by panic attack-associated hypocapnic hyperventilation, which presumably caused a greater degree of deep cerebral hypoperfusion than would be expected with orthostatic tachycardia syndrome alone, ultimately leading to the patient’s symptoms, including syncope. In conclusion, monitoring the ventilation and/or arterial CO₂ level during head-up tilt table testing is occasionally required when evaluating patients with postural syncope.

The effectiveness of packed therapy with three drugs in Helicobacter pylori eradication in Japan

Primary Helicobacter pylori eradication rate using triple therapy (a proton pump inhibitor [PPI] + amoxicillin [AMPC] + clarithromycin [CAM], over 7 days) is showing a declining trend. In this study we report recent eradication rates and have evaluated the usefulness of a pack preparation of three drugs. H. pylori eradication rate was 85.1% (57/67) in 2004 but then fell to 75.2% (79/105) in 2005, 70.1% (68/97) in 2006 and 69.9% (58/83) in 2007. With the introduction of packs (lansoprazole [LPZ] 60 mg, AMPC 1500 mg, CAM 400 mg) the eradication rate recovered to 78.0% (110/141) in 2008. A comparative study in 2008 delineated that the eradication rate in the pack group (88.4%, 38/43) was significantly higher than that of the conventional group (73.5%, 72/98). These results suggest that packs of eradication medicine are useful in increasing eradication success.

Isolation and identification of a diuretic hormone from the tobacco hornworm, Manduca sexta

A diuretic hormone (DH) has been isolated from pharate adult heads of Manduca sexta by a nine-step purification procedure. The primary structure of the amino-terminal 40 residues was determined by sequence analysis of intact DH. The structure of an amidated carboxyl-terminal tryptic hexapeptide was characterized by sequence analysis of the peptide, and this hexapeptide was later compared by reversed-phase liquid chromatography with two synthetic hexapeptides with the free acid or amide at the carboxyl terminus. The complete structure of M. sexta DH was established as a 41-residue peptide without disulfide bonds: H-Arg-Met-Pro-Ser-Leu-Ser-Ile-Asp-Leu-Pro-Met-Ser-Val-Leu-Arg-Gln-Lys-Leu-Ser -Leu-Glu-Lys-Glu-Arg-Lys-Val-His-Ala-Leu-Arg-Ala-Ala-Ala-Asn-Arg-Asn-Phe-Leu- Asn-Asp-Ile-NH(2). M. sexta DH was synthesized and shown to have chromatographic and biological properties identical with those of the native material. Synthetic DH stimulated fluid excretion in vivo upon injection into larval M. sexta and newly emerged adult Pieris rapae. M. sexta DH has considerable sequence homology with corticotropin-releasing factor, urotensin I, and sauvagine.

Amino acid sequence of a prothoracicotropic hormone of the silkworm Bombyx mori

We have determined the complete amino acid sequence of 4K-PTTH-II, one of three forms of the M(r) 4400 prothoracicotropic hormone of the silkworm Bombyx mori, active to brainless pupae of Samia cynthia ricini. Like vertebrate insulin, it consists of two nonidentical peptide chains (A and B chains). The A chain consists of 20 amino acid residues. The B chain is a mixture of four microheterogeneous peptides, two of which consist of 28 residues, and the other two, of 26 residues. 4K-PTTH-II has considerable sequence homology (40%) with human insulin, and it resembles porcine relaxin both in the carboxyl-terminal cysteine residue of the A chain and in the amino-terminal pyroglutamic acid residue of the B chain. The identical distribution of the six cysteine residues also indicates that 4K-PTTH-II belongs to the insulin family.

Ets-1 promotes the progression of cerebral aneurysm by inducing the expression of MCP-1 in vascular smooth muscle cells

Cerebral aneurysm (CA) rupture is one of the leading causes of stroke death. Recent experimental studies suggest that the pathophysiology of CA is closely associated with inflammation. A transcription factor, Ets-1, has been shown to regulate vascular inflammation and remodeling in a physiological and pathological condition. The expression and role of Ets-1 in CA development has been investigated in this study. Ets-1 was expressed and activated mainly in vascular smooth muscle cells (VSMCs) in both experimentally induced rat CAs and human CA walls by immunohistochemistry, western blotting and enzyme-linked mobility shift assay. The downstream target of Ets-1 in CA development was identified by chromatin immunoprecipitation (CHIP) analysis. CHIP analysis revealed that Ets-1 transactivated monocyte chemoattractant protein-1 (MCP-1) expression in CA walls. Treatment with ets decoy oligodeoxynucleotides resulted in the prevention of CA enlargement, upregulation of MCP-1 expression and increase in macrophage accumulation in CA walls. In conclusion, Ets-1 mediates MCP-1 expression in VSMCs in CA walls, thus promoting the progression of CAs. Inhibition of DNA-binding activity of Ets-1 may lead to the prevention of human CA enlargement and rupture. Results of this study will provide us a clue to a novel therapeutic strategy for CAs.