Dendritic cell SIRPα regulates homeostasis of dendritic cells in lymphoid organs

Signal regulatory protein α (SIRPα), an immunoglobulin superfamily protein that is expressed predominantly in myeloid lineage cells such as dendritic cells (DCs) or macrophages, mediates cell–cell signaling. In the immune system, SIRPα is thought to be important for homeostasis of DCs, but it remains unclear whether SIRPα intrinsic to DCs is indeed indispensable for such functional role. Thus, we here generated the mice, in which SIRPα was specifically ablated in CD11c⁺ DCs (Sirpa^ΔDC). Sirpa^ΔDC mice manifested a marked reduction of CD4⁺ CD8α^– conventional DCs (cDCs) in the secondary lymphoid organs, as well as of Langerhans cells in the epidermis. Such reduction of cDCs in Sirpa^ΔDC mice was comparable to that apparent with the mice, in which SIRPα was systemically ablated. Expression of SIRPα in DCs was well correlated with that of either endothelial cell‐selective adhesion molecule (ESAM) or Epstein–Barr virus‐induced molecule 2 (EBI2), both of which were also implicated in the regulation of DC homeostasis. Indeed, ESAM⁺ or EBI2⁺ cDCs were markedly reduced in the spleen of Sirpa^ΔDC mice. Thus, our results suggest that SIRPα intrinsic to CD11c⁺ DCs is essential for homeostasis of cDCs in the secondary lymphoid organs and skin.     

Autochthonous Dengue Fever,Tokyo, Japan, 2014

After 70 years with no confirmed autochthonous cases of dengue fever in Japan, 19 cases were reported during August–September 2014. Dengue virus serotype 1 was detected in 18 patients. Phylogenetic analysis of the envelope protein genome sequence from 3 patients revealed 100% identity with the strain from the first patient (2014) in Japan.     

Possible Cerebral Vasculitis in a Case with Rheumatoid Arthritis

Cerebral rheumatoid vasculitis (CRV) is a rare, fatal, and diagnostically challenging disorder. We herein report an 81-year-old woman with a 4-year history of rheumatoid arthritis who presented with a fever, progressive disturbance of consciousness, high level of rheumatoid factor, and hypocomplementemia. The enhancement of the perforating branches in the left middle cerebral artery led us to suspect CRV. A brain biopsy could not be performed. After we intensified steroid therapy, the size of the cerebral lesions temporarily decreased. However, recurrence in the left frontal lobe occurred one month later, and the patient subsequently died. Early intensive treatments may be needed for CRV.     

Influence of inhaled corticosteroids on community-acquired pneumonia in patients with bronchial asthma

OBJECTIVE: The aim of the present study was to evaluate the influence of inhaled corticosteroids (ICS) on community-acquired pneumonia (CAP) in patients with asthma. PATIENTS AND METHODS: All asthmatic patients who required hospitalization for CAP from the beginning of 1989 through December 2001 were enrolled in this retrospective study. Patients who used oral corticosteroids daily were excluded. Patients were divided into two groups based on whether or not they used ICS, and we analyzed clinical characteristics of the pneumonia. Sixty-two patients (28 males, 34 females; mean age, 54.5 years) were enrolled in this study. Thirty-seven of 62 patients used ICS, with the mean dosage being 777.9 microg/day. RESULTS: We found no significant differences between the two groups with regard to mean age, serum albumin level, duration of asthma, pulmonary function and frequency of intravenous infusion of corticosteroids in the outpatient department. There were no significant differences in body temperature, white blood cell count, and CRP value upon admission between the two groups. Differences were not significant in the period of resolution of the pneumonia or in the frequency of pathogens identified between the two groups. CONCLUSION: ICS therapy appears to have no influence on CAP in patients with asthma. We recommend that ICS should be continued to control asthma with adequate antibiotic therapy when asthmatic patients have CAP.     

Voxel-based analysis of age and gender effects on striatal [123I] FP-CIT binding in healthy Japanese adults

Annals of Nuclear Medicine - Although previous studies have investigated age and gender effects on striatal subregional dopamine transporter (DaT) binding, these studies were mostly based on a...     

Expression of pulmonary VEGF family declines with age and is further down-regulated in lipopolysaccharide (LPS)-induced lung injury

Vascular endothelial growth factor (VEGF) is a survival factor in endothelial cells and a promoter of angiogenesis that reportedly plays a pivotal role protecting against injury. In aged humans and animals, lung injuries are generally more serious and cause higher mortality. We thus hypothesized that the expression of VEGF and its related molecules in the lung declines with age. In this study, we first examined the expression of VEGF family (VEGF-A, -B, -C and -D), VEGF-A isoforms (VEGF120, 164, 188), and VEGF-specific receptors (VEGFR-1: Flt-1; VEGFR-2: Flk-1 and VEGFR-3: Flt-4) by quantitative RT-PCR in lungs from young and old mice. Expression of all these except for VEGF-D was significantly lower in old mice than in young mice. We then subjected young and old mice to lipopolysaccaride (LPS)-induced lung injury. Old animals demonstrated poor survival and prolonged lung inflammation when compared with young counterparts. At 24 and 72 h after intratracheal LPS administration, expression of the examined factors was down-regulated in the lungs irrespective of age. In conclusion, pulmonary expression of the VEGF family and their receptors declines with age, and is further down-regulated in LPS-induced lung injury, although the mechanism of age- and/or injury-related down-regulation of VEGF remains unknown.     

A giant retention cyst of the pancreas (cystic dilatation of dorsal pancreatic duct) associated with pancreas divisum

We describe a rare case of pancreas divisum associated with a giant retention cyst (cystic dilatation of the dorsal pancreatic duct), presumably formed following obstruction of the minor papilla. The patient was treated by pancreatico(cysto)jejunostomy. A 50-year-old man was admitted with complaints of increasing upper abdominal distension and body weight loss. There was no previous history of pancreatitis, gallstones, drinking, or abdominal injury. An elastic-hard tumor-like resistance was palpable in the upper abdomen. Computed tomography and ultrasound (US) examinations revealed a giant cystic lesion expanding from the pancreas head to the tail. Endoscopic retrograde cholangiopancreatography findings showed a looping pancreatic duct which drained only the head and uncinate process of the pancreas to the main papilla. A US-guided puncture to the cystic lesion revealed that the lesion continued to the main pancreatic duct in the tail of pancreas. The lesion was connected to a small cystic lesion, which was located inside the minor papilla, and ended there. The amylase level in liquid aspirated from the cyst was 37 869 IU/l, and the result of cytological examination of the liquid showed class II. A pancreatico(cysto)jejunostomy was performed, with the diagnosis being pancreas divisum associated with a retention cyst following obstruction of the minor papilla. The histological findings of a specimen from the cyst wall revealed that the wall was a pancreatic duct covered with mildly inflammatory duct epithelium; there was no evidence of neoplasm. The patient is currently well, and a CT examination 2 years after the operation showed disappearance of the cyst and normal appearance of the whole pancreas. Received: April 24, 2001 / Accepted: September 14, 2001