The role of microglia in the pathobiology of neuropathic pain development: what do we know?

Neuropathic pain, a maladaptive and chronic condition that can develop after a lesion or disease affecting the somatosensory system, is characterized by allodynia, hyperalgesia and spontaneous pain, and comorbidities such as sleep deprivation, depression and anxiety. The activation of microglial cells in response to nerve injury has been implicated in the development of neuropathic pain. Mediators such as Neuregulin-1, matrix metalloproteinase (MMP)-2, MMP-9, The chemokine (C-C motif) ligand 2 (CCL2) and fractalkine are released after nerve injury and are involved in the activation of microglial cells. These activated cells in turn release factors that increase the excitation and decrease the inhibition of interneurons. Microglial cells release factors such as interleukin (IL)-6, IL-1ß and tumour necrosis factor-α (TNF-α) that cause the painful symptoms. It is becoming increasingly apparent that an intricate network of cytokines and cellular signalling mechanisms underpin the complex relationship between microglia and various cell types including neurones, astrocytes, oligodendrocytes, mast cells and T-cells. Although the precise mechanism of action of microglial cells in producing neuropathic pain has not been completely elucidated, research into these different activating factors and cytokines is providing further insight into the role of microglial cells in the development and maintenance of neuropathic pain. Further studies also are required to elucidate how "pain" mediators act on neurones and how the interactions between these mediators, or between neurones and glia in the presence of these mediators occur, in order to develop effective therapies for the management of neuropathic pain.

The first report of the thyroid function of haemophilic patients with HIV/HCV co-infection in Japan.

INTRODUCTION: A high incidence of thyroid dysfunction is reported in patients with HIV or HCV mono-infection. We have conducted a periodic medical examination including the thyroid function for haemophilic patients with HIV/HCV co-infection due to contaminated blood products. METHODS: We examined the thyroid function (as assessed by the FT3, FT4 and TSH levels) in 45 haemophilic patients, including thyroglobulin and auto-antibody, antithyroglobulin antibody, antithyroid peroxidase antibody and anti-TSH receptor antibody in 28 patients. RESULTS: All the patients were males (median age: 42 years; range: 29-66). The median values of thyroid function were FT3 3.36 pg mL(-1) , FT4 1.125 ng mL(-1) and TSH 1.65 µIU mL(-1) . Five patients (11.1%) had high TSH levels. In 28 patients in whom the presence of auto-antibodies was examined, the median age was 47 years of age. The median value of thyroglobulin was 16 ng mL(-1) and two patients showed high levels of thyroglobulin. The presence of anti-TSH receptor antibody of all the patients was negative, but one patient (3.5%) was positive of antithyroid peroxidase antibody and antithyroglobulin antibody. CONCLUSIONS: Since 0.68-3.6% of the general healthy population is reported to show hypothyroidism, our data showed that the proportion of hypothyroidism in haemophilic patients with HIV/HCV co-infection was more frequent than that of the normal population.

Studies on expression of aldehyde dehydrogenase in normal and cancerous tissues of thyroids.

Recently published articles have reported the controversial data regarding expression of aldehyde dehydrogenase isozyme 1A1 (ALDH1A1), a potential candidate marker for normal and cancer stem cells (CSCs), in thyroid tissues. These data prompted us to re-evaluate expression of ALDH1A1 in normal and cancerous thyroid tissues by 2 different means. The first method was immunohistochemistry with 2 different anti-ALDH1A1 antibodies from distinct companies. Following validating the integrity of these 2 antibodies by Western blotting with ALDH-expressing and nonexpressing cancer cell lines and immunohistochemistry with breast and colon tissues, we report here significant and comparable expression of ALDH1A1 in both normal and cancerous thyroid tissues with both antibodies. Next, relative expression levels of ALDH isozymes were evaluated by reverse transcription-polymerase chain reaction (RT-PCR), revealing that ALDH1A1 was the most highly expressed isozyme followed by ALDH9A1 and relative expression patterns of isozymes were very similar in normal and cancerous tissues. All these data demonstrate that thyroid cells of normal and cancer origins do express ALDH1A1 and to a lesser extent 9A1. Further study will be necessary to study functional significance of ALDH1A1 in the function and behaviors of thyroid normal and cancer stem cells.

Evaluation of the operative methods for Graves' disease.

AIM: In Japan, surgery for Graves' disease (GD), which is considered to be a radical therapy, has been restricted by various guidelines. Nevertheless, some patients benefit from surgery. We sought to identify a reasonable operative method for GD by comparing the efficacy and safety among patients undergoing different extents of thyroidectomy. METHODS: A total of 162 patients underwent thyroidectomy for GD between 2003 and 2012 in our department. We compared the clinical factors among those who underwent subtotal thyroidectomy (ST), near-total thyroidectomy (NTT), and total thyroidectomy (TT). RESULTS: The ST, NTT, and TT groups included 111, 21, and 30 patients, respectively. The patient sex, period between disease onset and surgery, and preoperative thyroidal function were not substantially different among the three groups. With regard to surgical variables, the duration of surgery, amount of blood loss, and postoperative length of hospitalization were not substantially different among the three groups. Postoperative recurrent laryngeal nerve (RLN) palsy was transient in all cases, but the rate was significantly higher in the TT group compared to the other two groups (P<0.001). The incidences of transient hypocalcemia and permanent hypoparathyroidism were not substantially different among the groups. The proportion of patients who required the postoperative administration of levothyroxine was significantly lower in the ST group compared to the TT and NTT groups. Hyperthyroidism recurrence was noted in eight patients in the ST group (7.2%). CONCLUSION: NTT for GD is thus considered to be a reasonable operative method regarding both efficacy and safety.

Intraoperative portal venous pressure and long-term outcome after curative resection for hepatocellular carcinoma.

BACKGROUND: Outcomes of liver resection for hepatocellular carcinoma (HCC) have improved owing to better surgical techniques and patient selection. Portal hypertension may influence outcome but the preoperative definition and role of portal hypertension are far from clear. The aim of this study was to elucidate the influence of portal venous pressure (PVP) measured directly during surgery on outcomes of liver resection in patients with HCC. METHODS: Patients who had resection of HCC between 1997 and 2009, and who underwent direct measurement of PVP immediately after laparotomy were enrolled. These patients were divided into groups with high (at least 20 cmH(2)O) and low (less than 20 cmH(2)O) PVP. The influence of PVP on overall and recurrence-free survival was analysed and prognostic factors were identified. RESULTS: A total of 177 patients were enrolled, 129 in the low-PVP group and 48 in the high-PVP group. The 5-year overall survival rate (63·7 versus 31 per cent; P < 0·001) and recurrence-free survival rate (52·5 versus 12 per cent; P < 0·001) were significantly higher in patients with low PVP. In multivariable analysis, two or more tumours, tumour diameter at least 5 cm, high PVP, grade B liver damage and Hepatic Activity Index (HAI) grade 7 or more were significant predictors of poorer survival after liver resection. Two or more tumours, tumour diameter at least 5 cm and HAI grade 7 or more were significant predictors of poorer recurrence-free survival. CONCLUSION: High PVP was associated with poor long-term outcome after liver resection for HCC.

Is liver-targeted FOXp3 staining beneficial after living-donor liver transplantation?

As treatments for acute cellular rejection (ACR) and recurrent hepatitis caused by hepatitis C virus (HCV) are dramatically different, making a precise diagnosis is considered to be essential in patients after liver transplantation. Therefore, we investigated whether immunohistochemical detection of FOXp3, a marker for regulatory T cells (CD4+ CD25+), could be used to differentiate between recurrent hepatitis C and ACR. From a group of 103 cases of living-donor liver transplantation (LDLT), 48 samples were taken via liver biopsy from 20 patients with HCV infection. An initial diagnosis was made based on hematoxylin and eosin staining, which was scored with the hepatitis activity index (HAI) grading, whereas ARC was scored with the rejection activity index (RAI). The FOXp3 immunohistochemical staining on serial specimens was retrospectively analyzed, scoring from 0 to III. The time after LDLT was a median of 270 (range: 14-2000) days, whereas the median number of biopsies per patient was 3 (range: 1-8). The HAI was significantly different between 0 vs. I, and II vs. III, in terms of the FOXp3 score. On the other hand, a significant difference in the RAI was only found between 0 vs. I. In conclusion, FOXp3 may represent a surrogate marker for recurrent HCV infection after LDLT.

Recurrence-free survival more than 10 years after liver resection for hepatocellular carcinoma.

BACKGROUND: High recurrence rates after liver resection with curative intent for hepatocellular carcinoma (HCC) remain a problem. The characterization of long-term survivors without recurrence after liver resection may help improve the therapeutic strategy for HCC. METHODS: A nationwide Japanese database was used to analyse 20 811 patients with HCC who underwent liver resection with curative intent. RESULTS: The 10-year recurrence-free survival rate after liver resection for HCC with curative intent was 22.4 per cent. Some 281 patients were recurrence-free after more than 10 years. The HCCs measured less than 5 cm in 83.2 per cent, a single lesion was present in 91.7 per cent, and a simple nodular macroscopic appearance was found in 73.3 per cent of these patients; histologically, most HCCs showed no vascular invasion or intrahepatic metastases. Multivariable analysis revealed tumour differentiation as the strongest predictor of death from recurrent HCC within 5 years. CONCLUSION: Long-term recurrence-free survival is possible after liver resection for HCC, particularly in patients with a single lesion measuring less than 5 cm with a simple nodular appearance and low tumour marker levels.

Six National University Consortium in Liver Transplant Professionals Training (SNUC-LT) Program in Japan.

BACKGROUND: There has been no public structured training program for transplant surgeons in Japan. However, such a program is crucial for optimizing liver transplant surgery and training young professionals in liver transplant surgery. A comprehensive training program was recently developed and the underlying concepts, structure and curriculum, and results of this program are described here. METHODS: We developed a 3-year training program in 2014 called the Six National University Consortium in Liver Transplant Professionals Training (SNUC-LT) program supported by the Ministry of Education, Culture, Sports, Science, and Technology. This program is based on strong cooperation among 6 national universities (Kumamoto, Okayama, Nagasaki, Kanazawa, Niigata, and Chiba Universities). The program includes various courses to help trainees learn transplant theory and practice as well as to teach surgical skills required to safely perform transplant surgery. RESULTS: Three trainees completed the specially designed 3-year curriculum. They attended lectures on transplant theory for an average of 59 hours and participated in an average of 44 liver transplant surgeries and 51 liver resections for transplant practice. Trainees from low-volume centers had sufficient opportunities to attend operations in high-volume centers because of the cooperative agreement among the universities. After finishing the program, the trainees were certified as talent-proven liver transplant surgeons. CONCLUSIONS: The SNUC-LT program is the first national program in Japan to have strong professional support. Our multicenter program enables young surgeons to have more abundant knowledge, more extensive experience, better surgical skills, and smoother communication skills in the field of liver transplantation.

Endothelin receptor subtype B mediates synthesis of nitric oxide by cultured bovine endothelial cells.

Endothelins (ET) produce endothelium-dependent vasodilation through nitric oxide (NO) synthesis. The present study was designed to elucidate the cellular mechanism by which ET induces synthesis and release of endothelium-derived NO by cultured bovine endothelial cells (EC). Binding studies revealed that bovine EC membrane had the binding sites of a novel agonist (BQ3020) for non-isopeptide-selective receptor subtype (ETB). Affinity labeling studies showed a major labeled band with the apparent molecular mass of 50 kD. Northern blot analysis demonstrated the expression of mRNA for ETB receptor. BQ3020 rapidly and dose dependently induced formation of inositol-1,4,5-triphosphate and increased intracellular Ca2+ concentrations in fura-2-loaded cells. Concomitantly, BQ3020 dose dependently stimulated production of both nitrate/nitrite (NOx) and cyclic GMP; a highly significant correlation existed between NOx and cGMP production. The stimulatory effect on NOx and cGMP production by ETB agonist was inhibited by NO synthase inhibitor monomethyl-L-arginine; this effect was reversed by coaddition of L-arginine, but not D-arginine. NOx and cGMP production stimulated by BQ3020 was inhibited by pretreatment with pertussis toxin. ETB agonist-induced NOx production was blocked by a calmodulin inhibitor and an intracellular Ca2+ chelator, but not by an extracellular Ca2+ chelator or a Ca2+ channel blocker. These data suggest that endothelins stimulate ETB receptor-mediated phosphoinositide breakdown via pertussis toxin-sensitive G-protein(s), which triggers release of intracellular Ca2+, thereby activating Ca2+/calmodulin-dependent NO synthase in EC.

The association of DNA repair gene polymorphisms with the development and progression of renal cell carcinoma.

BACKGROUND: DNA repair enzymes repair some of the DNA damage associated with risk factors for renal cell carcinoma (RCC), including smoking. DNA repair gene polymorphisms modulate the repair capacity and might influence individual risk and progression of RCC. We examined associations between functional polymorphisms and risk, clinicopathologic characteristics and survival of RCC. PATIENTS AND METHODS: The study groups comprised 215 RCC patients and 215 age- and gender-matched healthy controls. Polymorphisms in xeroderma pigmentosum complementation groups C, D and G and X-ray repair cross-complementing groups 1 and 3 genes were genotyped. RESULTS: No significant differences in DNA repair genotype were observed between RCC cases and controls. In all patients, however, greater numbers (> or =3) of total variant alleles in all DNA repair genes studied were associated with less frequent venous extension (P = 0.0079). In smokers, some genotypes were associated with characteristics of RCC (Ps < or = 0.0067) and smokers with greater numbers of total variant alleles had improved overall survival (P = 0.040). CONCLUSION: These results suggest that DNA repair gene polymorphisms may not influence RCC susceptibility, but that some of them may influence RCC progression, especially in smokers, possibly due to altered DNA repair capacity by these polymorphisms.

Alpha3beta4-nicotinic receptors mediate adrenergic nerve- and peptidergic (CGRP) nerve-dependent vasodilation induced by nicotine in rat mesenteric arteries.

BACKGROUND AND PURPOSE: Previous studies demonstrated that nicotine-induced endothelium-independent vasodilation is mediated by perivascular adrenergic nerves and nerves releasing calcitonin gene-related peptide (CGRPergic nerves). We characterized the nicotinic acetylcholine (ACh) receptor subtype underlying the vasodilation in response to nicotine in rat mesenteric arteries. EXPERIMENTAL APPROACH: Rat mesenteric vascular beds without endothelium were contracted by perfusion with Krebs solution containing methoxamine and the perfusion pressure was measured with a pressure transducer. KEY RESULTS: Perfusion of nicotine (1-100 microM) for 1 min caused a concentration-dependent decrease in perfusion pressure due to vasodilation. Perfusion of (+/-)-epibatidine (1-100 nM) (non-selective agonist) or (-)-cytisine (1-100 microM) (partial agonist for nicotinic beta2 subtype and full agonist for nicotinic beta4 subtype) induced vasodilation in a concentration-dependent manner. Vasodilation induced by nicotine, (-)-cytisine- and (+/-)-epibatidine was markedly attenuated by guanethidine (5 microM) and pretreatment with capsaicin (1 microM). Mecamylamine (relatively selective antagonist for alpha3beta4 subtype), but not dihydro-beta-erythroidine (selective antagonist for alpha4beta2 subtype) or alpha-bungarotoxin (selective antagonist for alpha7 subtype), markedly inhibited nicotine-induced vasodilation. Nicotine-induced vasodilation was inhibited by methyllycaconitine at high concentrations (>1 microM), which non-selectively antagonize nicotinic receptors, while a low concentration of 10 nM, which selectively antagonizes alpha7 subtype, had no effect. (-)-Cytisine and (+/-)-epibatidine-induced vasodilation were abolished by mecamylamine. CONCLUSION AND IMPLICATIONS: These results suggest that the nicotinic alpha3beta4 receptor subtype, but not the alpha7 and alpha4beta2 subtypes, is responsible for the vasodilation in rat mesenteric arteries induced by nicotine- and nicotinic ACh receptor agonists through stimulation of adrenergic and CGRPergic perivascular nerves.

Cerebellar ataxia in a patient receiving calcineurin inhibitors after living donor liver transplantation: a case report.

Neurological complications of calcineurin inhibitors are frequent problems after transplantation. Cerebellar ataxia with other neurological findings and an abnormal density area in the subcortical white matter are found by MRI in the brains of most patients with central nervous system complications caused by calcineurin inhibitors. Such neurological complications are not life-threatening, but have a negative impact on the quality of life. We describe a 58-year-old woman who developed cerebellar ataxia at 4 days after living donor liver transplantation. She walked with a swaying gait, and after walking for 5 minutes she was unable to stand. Her symptoms persisted after a change from tacrolimus to cyclosporine, but dose reduction of cyclosporine and addition of mycophenolate mofetil cured the ataxia. We diagnosed a case of cerebellar ataxia without leukoencephalopathy or other neurological symptoms, as a new complication of calcineurin inhibitor treatment. We concluded that careful attention should be paid to neurological complications of calcineurin inhibitors.

[Preoperative pulseless electrical activity of acute type A aortic dissection; report of a case].

An 80-year-old man with acute type A aortic dissection, who was preoperatively observed in the intensive care unit, suddenly became unresponsive. The patient was immediately intubated, but a pulse check was delayed because the cardiac monitor seemingly showed a normal sinus rhythm. Bedside echocardiography, while continuing cardiopulmonary resuscitation, revealed massive pericardial effusion. It indicated the patient's cardiac arrest was pulseless electrical activity (PEA) due to cardiac tamponade. After pericardiocentesis, a perfusion rhythm was restored with palpable distal pulse. He successfully underwent a prosthetic graft replacement of the ascending aorta and was discharged after physical rehabilitation.

Recurrent Hepatitis B and D Virus Infection in a Liver Transplant Recipient.

Hepatitis B virus (HBV) and hepatitis delta virus (HDV) co-infections progress rapidly and lead to cirrhosis. In Japan, the prevalence of HBV and HDV co-infected patients is low. Therefore, there are few reports of patients with HBV and HDV co-infection having undergone liver transplantation. Herein, we report a rare case of recurrence of HBV and HDV in a 41-year-old man who underwent living donor liver transplantation 4 years prior.

Mechanotransduction of rat aortic vascular smooth muscle cells requires RhoA and intact actin filaments.

The growth-promoting effect of mechanical stress on vascular smooth muscle cells (VSMCs) has been implicated in the progress of vascular disease in hypertension. Extracellular signal-regulated kinases (ERKs) have been implicated in cellular responses, such as vascular remodeling, induced by mechanical stretch. However, it remains to be determined how mechanical stretch activates ERKs. The cytoskeleton seems the most likely candidate for force transmission into the interior of the cell. Therefore, we examined (1) whether the cytoskeleton involves mechanical stretch-induced signaling, (2) whether Rho is activated by stretch, and (3) whether Rho mediates the stretch-induced signaling in rat cultured VSMCs. Mechanical stretch activated ERKs, with a peak response observed at 20 minutes, followed by a significant increase in DNA synthesis. Treatment with the ERK kinase-1 inhibitor, PD98059, inhibited the stretch-induced increase in DNA synthesis. Cytochalasin D, which selectively disrupts the network of actin filaments, markedly inhibited stretch-induced ERK activation. In the control state, RhoA was observed predominantly in the cytosolic fraction, but it was translocated in part to the particulate fraction in response to mechanical stretch. Botulinum C3 exoenzyme, which inactivates Rho p21 (known to participate in the reorganization of the actin cytoskeleton), attenuated stretch-induced ERK activation. Inhibition of Rho kinase (p160ROCK) also suppressed stretch-induced ERK activation dose dependently. Our results suggest that mechanotransduction in VSMCs is dependent on intact actin filaments, that Rho is activated by stretch, and that Rho/p160ROCK mediates stretch-induced ERK activation and vascular hyperplasia.

Evaluation of resectability after neoadjuvant chemotherapy for primary non-resectable colorectal liver metastases: A multicenter study.

BACKGROUND/AIM: The Kyushu Study Group of Clinical Cancer (KSCC) previously reported the safety and efficacy of neoadjuvant chemotherapy with mFOLFOX6 + bevacizumab for H2/H3 liver metastases of colorectal cancer. The aim of the current study was to evaluate the resectability of these metastases before and after chemotherapy as determined by independent liver surgeons. METHODS: Between May 2008 and April 2010, 40 patients were registered in a multicenter phase 2 trial of neoadjuvant chemotherapy (KSCC 0802). In Study 1, 5 independent liver surgeons from five different KSCC centers evaluated the resectability of liver metastases of colorectal cancer based on imaging studies performed before and after chemotherapy. Each surgeon was blinded to the other surgeons' evaluations. In addition, no information about the patients' characteristics was provided. In Study 2, 3 surgeons evaluated the resectability of these lesions based on imaging studies with discussion with each other, with the surgeons being provided with information on the patients' characteristics. RESULTS: In Study 1, 13 patients (36.1%) were evaluated to be resectable at baseline, whereas 17 patients (47.2%) were evaluated to be resectable after chemotherapy. In Study 2, 4 patients (11.1%) were evaluated to be resectable at baseline, compared to 23 patients (63.9%) after chemotherapy. CONCLUSION: Neoadjuvant chemotherapy with mFOLFOX6 + bevacizumab was confirmed to increase the resectability of non-resectable liver metastases of colorectal cancer according to the independent assessments of surgeons.

Combined warfarin and antiplatelet therapy after St. Jude Medical valve replacement for mitral valve disease.

OBJECTIVES: The clinical effect of combined warfarin and antiplatelet therapy on the incidence of stroke and postoperative complications after mitral (plus aortic) valve replacement was studied and compared with that observed with warfarin therapy alone. BACKGROUND: It has been reported that combined warfarin and antiplatelet therapy may be effective but may be associated with an increased hemorrhagic risk. Therefore, definite benefits of the treatment in patients with an implanted prosthetic valve have not been clearly documented. METHODS: Between January 1980 and December 1992, 195 patients with a St. Jude Medical valve at the mitral (plus aortic) position were assigned to receive treatment with either warfarin alone (125 patients) or warfarin plus antiplatelet agents (70 patients), such as dipyridamole (150 or 300 mg daily, 14 patients) or ticlopidine (200 or 400 mg daily, 56 patients). A minimal dose of aspirin (10 to 40 mg) was added (29 patients) if the maximal platelet aggregation rate by collagen was not reduced. The target thrombotest level was 10% to 20%. RESULTS: The two treatment groups were similar with regard to gender and age distribution. The number of patients with atrial fibrillation, left atrial thrombus, history of previous stroke, simultaneous aortic valve operation and previously performed valve procedures were comparable in the two groups. Actuarial survival rate at 10 years was 98.3 +/- 1.7% (mean +/- SD) in the warfarin plus antiplatelet group and 90.3 +/- 3.2% in the warfarin group (p < 0.05 at 1 and 9 to 12 years). The actuarial stroke-free rate at 10 years was 95.3 +/- 3.4% and 84.3 +/- 3.8%, respectively (p < 0.05 by the generalized Wilcoxon test). The actuarial complication-free rate at 10 years was 89.4 +/- 4.3% and 67.9 +/- 4.8%, respectively (p < 0.05 by the generalized Wilcoxon test). No hemorrhagic complications were seen in the warfarin plus antiplatelet group. CONCLUSIONS: The results strongly indicate the effectiveness and safety of combined warfarin plus antiplatelet treatment after St. Jude Medical valve replacement for mitral (plus aortic) valve disease.

Role of necroptosis in the pathogenesis of solid organ injury.

Necroptosis is a type of regulated cell death dependent on the activity of receptor-interacting serine/threonine-protein (RIP) kinases. However, unlike apoptosis, it is caspase independent. Increasing evidence has implicated necroptosis in the pathogenesis of disease, including ischemic injury, neurodegeneration, viral infection and many others. Key players of the necroptosis signalling pathway are now widely recognized as therapeutic targets. Necrostatins may be developed as potent inhibitors of necroptosis, targeting the activity of RIPK1. Necrostatin-1, the first generation of necrostatins, has been shown to confer potent protective effects in different animal models. This review will summarize novel insights into the involvement of necroptosis in specific injury of different organs, and the therapeutic platform that it provides for treatment.