Chemogenetic Activation of Oxytocin Neurons Improves Pain in a Reserpine-induced Fibromyalgia Rat Model.

Fibromyalgia (FM) is a syndrome characterized by chronic pain with depression as a frequent comorbidity. However, efficient management of the pain and depressive symptoms of FM is lacking. Given that endogenous oxytocin (OXT) contributes to the regulation of pain and depressive disorders, herein, we investigated the role of OXT in an experimental reserpine-induced FM model. In FM model, OXT-monomeric red fluorescent protein 1 (OXT-mRFP1) transgenic rats exhibited increased depressive behavior and sensitivity in a mechanical nociceptive test, suggesting reduced pain tolerance. Additionally, the development of the FM-like phenotype in OXT-mRFP1 FM model rats was accompanied by a significant reduction in OXT mRNA expression in the magnocellular neurons of the paraventricular nucleus. OXT-mRFP1 FM model rats also had significantly fewer tryptophan hydroxylase (TPH)- and tyrosine hydroxylase (TH)-immunoreactive (ir) neurons as well as reduced serotonin and norepinephrine levels in the dorsal raphe and locus coeruleus. To investigate the effects of stimulating the endogenous OXT pathway, rats expressing OXT-human muscarinic acetylcholine receptor (hM3Dq)-mCherry designer receptors exclusively activated by designer drugs (DREADDs) were also assessed in the FM model. Treatment of these rats with clozapine-N-oxide (CNO), an hM3Dq-activating drug, significantly improved characteristic FM model-induced pathophysiological pain, but did not alter depressive-like behavior. The chemogenetically induced effects were reversed by pre-treatment with an OXT receptor antagonist, confirming the specificity of action via the OXT pathway. These results indicate that endogenous OXT may have analgesic effects in FM, and could be a potential target for effective pain management strategies for this disorder.

ANCA-Associated Vasculitis after Moderna COVID-19 Vaccination.

We experienced a case of myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis after Moderna COVID-19 vaccination. An 82-year-old woman developed pyrexia and general malaise one month after her third booster vaccine, and the symptoms persisted. Blood testing revealed inflammation, a high level of MPO-ANCA, and microscopic hematuria. MPO-ANCA-associated vasculitis was diagnosed by renal biopsy. The symptoms improved with steroid therapy. Common adverse reactions to mRNA vaccines against COVID-19 include pyrexia and general malaise, but MPO-ANCA-associated vasculitis can also occur. If pyrexia, prolonged general malaise, urinary occult blood, or renal impairment is observed, the onset of MPO-ANCA-associated vasculitis should be considered.

Oestrogen-dependent hypothalamic oxytocin expression with changes in feeding and body weight in female rats.

Oxytocin (OXT) is produced in the hypothalamic nuclei and secreted into systemic circulation from the posterior pituitary gland. In the central nervous system, OXT regulates behaviours including maternal and feeding behaviours. Our aim is to evaluate whether oestrogen regulates hypothalamic OXT dynamics. Herein, we provide the first evidence that OXT dynamics in the hypothalamus vary with sex and that oestrogen may modulate dynamic changes in OXT levels, using OXT-mRFP1 transgenic rats. The fluorescence intensity of OXT-mRFP1 and expression of the OXT and mRFP1 genes in the hypothalamic nuclei is highest during the oestrus stage in female rats and decreased significantly in ovariectomised rats. Oestrogen replacement caused significant increases in fluorescence intensity and gene expression in a dose-related manner. This is also demonstrated in the rats' feeding behaviour and hypothalamic Fos neurons using cholecystokinin-8 and immunohistochemistry. Hypothalamic OXT expression is oestrogen-dependent and can be enhanced centrally by the administration of oestrogen.

Chemogenetic activation of endogenous arginine vasopressin exerts anorexigenic effects via central nesfatin-1/NucB2 pathway.

We examined whether the chemogenetic activation of endogenous arginine vasopressin (AVP) affects central nesfatin-1/NucB2 neurons, using a transgenic rat line that was previously generated. Saline (1 mL/kg) or clozapine-N-oxide (CNO, 1 mg/mL/kg), an agonist for hM3Dq, was subcutaneously administered in adult male AVP-hM3Dq-mCherry transgenic rats (300-370 g). Food and water intake were significantly suppressed after subcutaneous (s.c.) injection of CNO, with aberrant circadian rhythmicity. The percentages of Fos expression in nesfatin-1/NucB2-immunoreactive neurons were significantly increased in the hypothalamus and brainstem at 120 min after s.c. injection of CNO. Suppressed food intake that was induced by chemogenetic activation of endogenous AVP was ablated after intracerebroventricularly administered nesfatin-1/NucB2-neutralizing antibody in comparison with vehicle, without any alteration of water intake nor circadian rhythmicity. These results suggest that chemogenetic activation of endogenous AVP affects, at least in part, central nesfatin-1/NucB2 neurons and may exert anorexigenic effects in the transgenic rats.

A Case of Neurosarcoidosis-Induced Syndrome of Inappropriate Secretion of Antidiuretic Hormone Diagnosed with Neuroendoscopy.

We treated a patient with neurosarcoidosis, which caused the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), in whom diagnosis was performed using neuroendoscopy. The patient was a 56-year-old female who was hospitalized for hyponatremia and diagnosed with SIADH based on a detailed examination. During the course, she developed impaired consciousness due to acute hydrocephalus, which improved after ventricular drainage. Head magnetic resonance imaging (MRI) confirmed nodular lesions at the floor of the third ventricle and the cerebral aqueduct. Neuroendoscopic biopsy led to the diagnosis of neurosarcoidosis. Her hyponatremia improved after steroid therapy. Neurosarcoidosis can cause SIADH, and complication of hydrocephalus may lead to a poor prognosis. Neuroendoscopy appears to be effective for the diagnosis of neurosarcoidosis with hydrocephalus and helps in deciding the treatment modality.

Infected Aneurysm after Endoscopic Submucosal Dissection.

A 79-year-old man on hemodialysis was hospitalized for further investigation. Early gastric cancer was diagnosed by gastrointestinal endoscopy and endoscopic submucosal dissection (ESD) was performed. Fever and abdominal pain thereafter developed, and a severe inflammatory response was observed on a blood test. Contrast computed tomography (CT) showed ulcer-like projections and soft tissue surrounding the aorta, from the celiac to left renal artery. An infected aneurysm was diagnosed. Although infected aneurysms developing after laparoscopic cholecystectomy or biopsy of contiguous esophageal duplication cyst have been reported, those developing after ESD have not. When fever and abdominal pain develop after ESD, an infected aneurysm should be considered and contrast CT performed.

Close association of vascular and valvular calcification and prognosis of patients on continuous ambulatory peritoneal dialysis.

In the present study, we examined the association between vascular and valvular calcification and the prognosis of patients on continuous ambulatory peritoneal dialysis (CAPD). Data were collected from the records of patients introduced onto CAPD therapy during 1999 - 2006 at the Department of Nephrology, Saitama Medical University. At the start of CAPD, cardiac and vascular echography were used to examine 162 patients (average age: 56 +/- 5 years; 58 men, 104 women; 43 with and 119 without diabetes) for evaluation of vascular and valvular calcification. Both vascular and valvular calcification were found in 32 patients. Vascular calcification was found in 16, and valvular calcification in 11. Over 5 years, 11 patients suffered from cardiovascular disease (7 with stroke, 4 with myocardial infarction). All of these patients had vascular or valvular calcification at the start of CAPD therapy. We also used Cox hazard analysis to examine values for Ca, P, Ca x P, intact parathyroid hormone (iPTH), and lipids. None of these values were independent contributory factors for incidence of cardiovascular disease in patients on CAPD. These data suggest the importance of vascular and valvular echography to evaluate patients on CAPD, especially at the start of CAPD therapy. Vascular and valvular calcification are important factors for determining the prognosis of patients on CAPD.

Risk factors and cause of removal of peritoneal dialysis catheter in patients on continuous ambulatory peritoneal dialysis.

In the present study, we examined the risk factors and causes for removal of the peritoneal dialysis (PD) catheter in patients on continuous ambulatory PD (CAPD). Data were collected from the records of patients who received CAPD therapy from 1995 to 2007 in the Department of Nephrology, Saitama Medical University. During that time, 473 patients were introduced onto CAPD therapy and the PD catheter was removed from 63 patients. Catheters were removed in 30 patients (47%) because of peritoneal infection, in 11 (17%) because of dialysis failure, in 8 (13%) because of neoplasm of the gastrointestinal tract, in 6 (10%) because of perforation of the gastrointestinal tract, in 2 (3%) because of laceration of PD catheter, and in 3 each (5%) because of transplantation and home hemodialysis therapy. Duration of CAPD was 5.6 +/- 1.2 years. In patients who experienced peritoneal infection, causative organisms were Staphylococcus (mainly methicillin-resistant S. aureus), Candida, Pseudomonas, and non tuberculous Mycobacterium. Failure to continue PD therapy related to dialysis deficiency. All patients were examined for encapsulating peritoneal sclerosis (EPS) by computed tomography (CT) enhanced using contrast material. In 9 cases in which the CT findings indicated EPS, treatment with oral prednisolone (20 mg daily) was started; the dose was then gradually reduced over 1 year. After removal of the PD catheter, no patient developed EPS. All removed catheters were examined using electron microscopy. The catheters from patients who experienced PD peritonitis revealed biofilm formation; however, no biofilm formation was found in PD catheters removed from patients without infection. Despite appropriate antibiotic therapy, peritoneal infection remains the major cause of PD catheter removal. Biofilm formation might be an obstacle to PD continuation.

Comparison and survival of patients receiving hemodialysis and peritoneal dialysis in a single center.

The influence of the type of dialysis on survival of patients with end-stage renal disease (ESRD) is controversial. To compare survival among patients with ESRD receiving peritoneal dialysis (PD) or hemodialysis (HD), we conducted a prospective cohort study in a single center from April 1995 to March 2005. During that period, 454 patients (161 women, 293 men; mean age: 61.7 +/- 14.4 years; 46.6% with diabetic nephropathy) were started on HD therapy, and 120 patients (40 women, 80 men; mean age: 54.5 +/- 11.3 years; 16.7% with diabetic nephropathy) were started on PD therapy; all patients were followed for at least 3 years. The 3-year survival rates were 65% for the HD patients and 81% for the PD patients (p < 0.05). The causes of death in patients undergoing HD were 52% cardiovascular 25% infectious diseases, and 12% cancer; in patients undergoing PD, the causes were 36% infectious diseases, 24% cardiovascular, and 6% cancer Median time from initiation of dialysis to study enrollment was 90 days for HD patients and 180 days for PD patients. Although patients in this study were not randomly assigned to their initial type of dialysis therapy, survival rate was found to be dependent on dialysis type. Moreover, this study suggests the importance of early referral and evaluation of risk factors in individual patients before they are started on dialysis therapy.

Valsartan cardio-renal protection in patients undergoing coronary angiography complicated with chronic renal insufficiency (VAL-CARP) trial: rationale and design.

BACKGROUND: Despite an increase in the frequency of coronary angiography (CAG) in Japan, the exact incidence of contrast-induced nephropathy (CIN) remains unknown in the Japanese population, especially in patients with chronic renal insufficiency. In addition, the nature of pharmacological interventions that would benefit the patients before or after procedures such as coronary bypass graft (CABG) and percutaneous coronary intervention (PCI) has not been fully investigated. METHODS: In the trial 500 patients with renal insufficiency (defined as a glomerular filtration rate (GFR) of between 89 and 30 ml . min(-1) . (1.73 m(-2)) following CAG will be randomly assigned to receive either valsartan, an angiotensin receptor blocker or angiotensin converting enzyme (ACE) inhibitor plus valsartan.1 The primary end-point is a change in the GFR of patients, which will be followed up for 3 years, including following CABG surgery or PCI. The incidence of cardiac events as well as the adverse effects of pharmacological intervention will be evaluated. In addition, the incidence of renal artery stenosis at the time of CAG will be reported also; however, the patients with renal artery stenosis will be excluded from the present study. CONCLUSION: The present study will provide data on: 1) the exact incidence and course of renal function of CIN after CAG; and 2) the comparative therapeutic benefit of pharmacological intervention with valsartan alone or with valsartan and an ACE inhibitor in combination in patients with coexisting coronary artery diseases and chronic renal insufficiency, regardless of whether they receive CABG or PCI. In addition to these studies, an estimate of the incidence of renal artery stenosis in these patients will be demonstrated.

An unusual form of crystal-forming chronic interstitial nephritis following long-term exposure to tosufloxacin tosilate.

Fluoroquinolones are known to cause acute renal failure because of interstitial nephritis with or without epithelioid granulomas. We report the first case of slowly progressive renal failure caused by crystal-forming chronic interstitial nephritis with non-Langerhans' cell histiocytosis after long-term exposure to a fluoroquinolone, tosufloxacin tosilate. Lesions consisted of spindle- to cuboidal-shaped histiocytes with minimal collagenous matrix and low-level lymphocyte infiltration replacing normal tubulointerstitial structure of the kidney. Histiocytes were positive for CD68, but negative for S-100, suggesting they were derived from macrophages. There were numerous rhomboid- to needle-shaped crystal deposits in the cytoplasm of histiocytes, which showed bright birefringence under polarized light. No immunoglobulin deposits were seen in the kidney, and no evidence of paraproteinemia/lymphoproliferative diseases was identified in this patient. Despite a negative drug lymphocyte-stimulating test result using tosufloxacin tosilate, withdrawal of the drug and treatment with steroids gradually improved renal function. In this report, we describe the clinical course and histopathologic findings of this patient and discuss the possible pathogenesis.

An atypical pattern of Epstein-Barr virus infection in a case with idiopathic tubulointerstitial nephritis.

Recently, Epstein-Barr virus (EBV) received attention because a latent form of its infection in renal proximal tubular epithelial cells was found to cause idiopathic, chronic tubulointerstitial nephritis. In this report, we describe the case of a patient with a replicative form of EBV infection, chronic active EBV infection (CAEBV), who developed acute tubulointerstitial nephritis and minimal change nephrotic syndrome. A renal biopsy revealed papillary infoldings of atypical tubular epithelium and adjacent dense infiltration of lymphocytes. Using in situ polymerase chain reaction methods, we detected the EBV genome in some of the infiltrating lymphocytes, but not in the tubular epithelial cells. EBV-infected T cells are thought to activate other educated T cells, as well as secrete an unrestricted variety of cytokines, thus playing a pivotal role in CAEBV and its end organ disease. Therefore, in our case, the CAEBV activated, educated T cells may have followed the EBV-infected lymphocytes as they infiltrated into the peritubular interstitium, and promoted focal tubular epithelial atypia and minimal change nephrotic syndrome. The long-term observation of such patients is important because CAEBV may progress into lymphoproliferative diseases.