Biomedical subjects

Hiroki Nakano

Publications and source records attributed to Hiroki Nakano.

11 recordsLinked to original sources

PubMed2006

Diffuse gastroduodenitis and pouchitis associated with ulcerative colitis.

We experienced a very rare case of ulcerative colitis (UC) accompanied with analogous lesions in the stomach, duodenum, and ileal J-pouch. Ileal J-pouch anal anastomosis was performed on a 29-year old woman in 1996. Six years later, she was admitted again to our hospital because of epigastralgia, nausea, watery diarrhea and low fever. Based on the results of endoscopic examination, we diagnosed it as pouchitis. Moreover, on hypotonic duodenography, expansion of the duodenal bulb and the descending portion were poor. Kerckring folds disappeared with typical lead-pipe appearance. The pathogenesis of the gastric and duodenal lesion in this patient was similar to that of the colonic lesions of UC. For the gastroduodenal lesions in this patient, symptomatic remission was obtained following administration of crushed mesalazine tablets (1500 mg/d) for 14 d with continuous administration of omeprazole. Firstly we used ciprofloxacin to treat pouchitis. On the fifth day, she got a fever because of catheter infection. In the catheter culture, methicillin-resistant Staphylococcus aureus (MRSA) was detected. Therefore we changed ciprofloxacin to vancomycin hydrochloride (Vancomycin). Vancomycin was very effective, and the stool frequency dramatically improved in three days. Now she continues to take mesalazine, but her condition is stable and there has been no recurrence of pouchitis.

Adult↗

PubMed2006

Incidence of and risk factors for dysplasia in mucosectomy area in ulcerative colitis patients undergoing restorative proctocolectomy.

BACKGROUND AND AIMS: We evaluated the incidence of dysplasia in the mucosectomy area using resected specimens to determine preoperative risk factors for the occurrence of dysplasia in this area. PATIENTS AND METHODS: We prospectively studied a consecutive series of 137 patients, each of whom underwent a restorative proctocolectomy with a mucosectomy and hand-sewn ileal J-pouch anal anastomosis between January 2003 and December 2004. Sections from the anal transitional zone mucosa were taken from the dentate line to 2.5 cm above the resected line and stained with hematoxylin and eosin then characterized as indefinite for dysplasia, low-grade dysplasia, and high-grade dysplasia based on the criteria of an international working group for rectal mucosal atypia. RESULTS: Dysplasia of the mucosectomy area was present in six (4.4%) of the patients, including one with low-grade and five with high-grade dysplasia. A multivariate analysis showed relations between age at time of surgery (>or=40 years) and duration of disease (>or=10 years) with a risk for development of mucosectomy area dysplasia. CONCLUSION: The incidence of dysplasia of the mucosectomy area was 4.4%, and preoperative risk factors were shown to be duration of disease and age at time of surgery.

Adolescent↗

PubMed2006

Postoperative joint symptoms: a risk factor for pouchitis in ulcerative colitis patients.

BACKGROUND: The prevalence and significance of joint symptoms appearing in patients with ulcerative colitis (UC) following a colectomy are unclear. AIM: We investigated the relationship between joint symptoms during steroid tapering following an ileal pouch-anal anastomosis (IPAA) and the cumulative risk for developing pouchitis. PATIENTS AND METHODS: The medical records of 571 patients who underwent an IPAA with a mucosectomy were retrospectively reviewed to evaluate their joint symptoms. A diagnosis of pouchitis was obtained using the Pouchitis Disease Activity Index (PDAI) and the cumulative risk of pouchitis was estimated using a Kaplan-Meier life table analysis. RESULTS: Joint symptoms during steroid tapering were reported by 126 (22.0%) of the UC patients and each of those had involvement of the small joints of the hand. The main symptoms were pain and stiffness, especially in the morning. The cumulative risk for developing pouchitis after 10 years was found to be 20% in patients who experienced joint symptoms during steroid tapering and 10% in those without those symptoms (p = 0.001). CONCLUSION: The presence of joint symptoms during steroid tapering is a significant risk factor for the development of pouchitis in patients who have undergone an IPAA for UC.

Adolescent↗

PubMed2006

Leukocyte removal therapy for ulcerative colitis does not affect postoperative complications.

BACKGROUND: We investigated the incidence of postoperative complications in patients treated with or without preoperative leukocyte removal therapy (LRT). METHODS: The case notes of 387 patients with ulcerative colitis (UC) who underwent surgical intervention were retrospectively reviewed. One hundred nine patients were treated with LRT within 8 weeks before surgery (LRT group), and 278 had not received LRT since at least 8 weeks before surgery (without LRT group). We reviewed the postoperative complications according to type of initial operation. RESULTS: Of the patients who underwent an ileal J-pouch anal anastomosis (IPAA) without an ileostomy, 3 (6.5%) in the LRT group developed pouch-related complications (PRC), while 11 (7.5%) in the without LRT group developed PRC. The overall postoperative complication rates were 28.3% in the LRT group and 21.8% in the without LRT group. For patients who underwent an IPAA with an ileostomy, the overall rates of postoperative complications were 39.1% in the LRT group and 31.8% in the without LRT group. Among those undergoing a total colectomy, 33.3% in the LRT group and 18.2% in the without LRT group had postoperative complications. No statistically significant differences were demonstrated between the two groups with respect to postoperative complications. CONCLUSIONS: Our results suggest that preoperative LRT does not influence the rate of postoperative complications in UC patients.

Adolescent↗

PubMed2005

Safety of one-stage restorative proctocolectomy for ulcerative colitis.

PURPOSE: The aim of this study was to compare clinical outcomes in patients with ulcerative colitis who underwent restorative proctocolectomy with and without diverting ileostomy. METHODS: A series of 245 consecutive patients who underwent ileal pouch anal anastomosis with mucosectomy with an ultrasonically activated scalpel (harmonic scalpel) was studied. Of these patients, 92 patients had a diverting ileostomy and 150 selected patients did not. The decision for or against an ileostomy was made at the end of the operation. RESULTS: Twelve patients (8 percent) in the group without ileostomy had pouch-related complications, which necessitated secondary ileostomy in five patients (3.3 percent). Intestinal obstruction developed in 17 patients (11.3 percent) who had no ileostomy and in 12 patients (13.0 percent) who underwent ileostomy. Two of 17 patients who had no ileostomy and 1 of 12 patients with ileostomy required laparotomy with division of adhesions, whereas the remaining patients responded to conservative measures. There were no significant differences in the incidence of postoperative complications after the initial operation between the two groups. In the group with ileostomy, the morbidity rate for ileostomy was 12.1 percent, and that for ileostomy closure was 18.7 percent. The total postoperative complication rate for the group with ileostomy was significant higher than that for the group without ileostomy. CONCLUSION: We conclude that restorative proctocolectomy with mucosectomy by use of an ultrasonically activated scalpel and without diversion is a superior therapeutic choice for selected patients.

Adolescent↗

PubMed2005

Venous thromboembolism in colorectal cancer patients with central venous catheters for 5-FU infusion-based pharmacokinetic modulating chemotherapy.

Colorectal cancer patients with central venous catheters (CVC) for pharmacokinetic modulating chemotherapy (PMC) have a substantial risk of venous thromboembolism (VTE). PMC, designed as a hybrid of lower metronomic and higher shorter plasma 5-FU concentrations, has been clinically successful. To determine the effectiveness and safety of D-dimer tests and multidetector-row CT (MDCT) for diagnosis in cancer patients with suspected VTE, we carried out a clinical outcome study on PMC outpatients. Patients received a D-dimer test before and after commencing the PMC regimen. MDCT was performed additionally if the D-dimer test appeared positive or showed signs of VTE. When CT results were positive for thromboembolism, anticoagulation was started. The overall prevalence of VTE in PMC patients was 2.0% (7 of 350 patients). In this study, 34 out of 102 colorectal cancer patients gave a positive D-dimer test (33.3%). CT identified venous thrombi in 2 of the 102 patients (2.0%), mural thrombosis on catheterized veins in another 3 patients (2.9%), and endothelial hyperplasia on catheterized veins in 8 patients (7.8%). The catheters of these patients did not show any significant abnormalities. Patients with negative D-dimer tests showed no signs or symptoms of VTE. In colorectal cancer patients receiving continuous 5-FU infusion via CVC, a D-dimer test can be safely used as the primary diagnostic test for ruling out VTE. We suggest 7.0 microg/ml as the D-dimer cut-off value. Thromboprophylaxis should be considered in the patients showing values >7.0 microg/ml.

Adult↗

PubMed2004

Incidence and therapeutic outcome of pouchitis for ulcerative colitis in Japanese patients.

AIM: The aim of this study was to examine the cumulative risk of pouchitis following restorative proctocolectomy for UC and FAP in Japanese patients, and to assess the response to medical treatment and its outcome. PATIENTS AND METHODS: 521 patients with UC and 117 FAP patients underwent proctocolectomy and received a J-shaped IPAA at our department of surgery. We investigated these patients using PDAI for the diagnostic criteria of pouchitis. RESULTS: Pouchitis occurred in only 32 UC patients (6.1%). The cumulative risk of developing pouchitis for a UC patient was 7% at 5 years after and 12% at 10 years after surgery. The medical treatment of acute pouchitis was usually oral metronidazole (250 mg twice daily) for 2 weeks or oral ciprofloxacin (200 mg thrice daily) in patients who could not tolerate metronidazole. Single episodes of pouchitis occurred in 21 patients (65.6%) and chronic or frequent relapses of pouchitis in 11 patients (34.4%). Three patients (9.4%) required re-ileostomy. Two patients (6.3%) required pouch excision. There were no patients with complicated dysplasia. CONCLUSION: The cumulative risk of pouchitis in Japanese UC patients is lower than that of western countries.

Adenomatous Polyposis Coli↗

PubMed2004

Contribution of CD1d-unrestricted hepatic DX5+ NKT cells to liver injury in Plasmodium berghei-parasitized erythrocyte-injected mice.

Inoculation with erythrocytes infected with Plasmodium berghei, a protozoan causing mouse lethal malaria, induces liver injury in mice, although the parasite cannot invade host hepatocytes at this infectious stage. As previously reported, hepatic infiltrates participate in this liver injury by exerting their perforin-dependent killing action. Here, we have investigated the cellular mechanisms underlying P. berghei-induced incidental liver injury. Hepatic lymphocytes from P. berghei-infected mice killed normal hepatocytes, but not ConA-induced lymphoblasts. Furthermore, the hepatic lymphocytes from infected C57BL/6 mice displayed cytotoxicity against hepatocytes from C57BL/6 and BALB/c mice, indicating MHC-unrestricted hepatocytotoxicity by these hepatic lymphocytes. NK cells were not involved in this hepatocytotoxicity. However, DX5+ cells sorted from the liver of infected CD1d-deficient mice killed normal hepatocytes, indicating that CD1d-independent DX5+ T cells are the effector cells. The hepatocytotoxicity of these hepatic DX5+ T cells did not require TCR engagement. These findings indicate that hepatic CD1d-independent DX5+ T cells play a critical role in P. berghei-induced liver injury. Our studies may have general implications for tissue injuries that are caused by 'bystander killing' or other poorly defined cell-mediated killing mechanisms.

Alanine Transaminase↗

PubMed2003

Persistent secretion of IL-18 in the skin contributes to IgE response in mice.

After exposure of the skin to microbes, the host develops skin-specific inflammation and an acquired immune response, in which keratinocytes (KC) and Langerhans cells play critical roles respectively. We established two animal models. (i) We examined the importance of KC-derived IL-18 for the systemic IgE response by using a skin transplantation model. As previously reported, transgenic mice (KCASP1Tg), that over-express caspase-1 in their KC, display high serum levels of IgE, and spontaneously develop chronic dermatitis by production of IL-18 and IL-1beta. We examined the capacity of transplantation of cutaneous lesions from KCASP1Tg to induce IgE production in wild-type or mutant mice with a syngeneic background. Transplantation of active cutaneous lesions, that expressed high levels of IL-18 and IL-1beta, induced long-lasting IgE production in wild-type mice without elevation of circulating IL-18 and IL-1beta. Furthermore, IL-18R-, CD4- or stat6-deficient mice transplanted with the lesions did not produce IgE, indicating that this IgE response is initiated by IL-18, and dependent on host-derived CD4(+) T cells and stat6. (ii) We investigated IL-18 secretion from KC upon stimulation with microbe products. Freshly isolated KC from wild-type mice secreted IL-18 in response to Protein A purified from Cowan 1 strain of Staphylococcus aureus (SpA), which often exacerbates human skin diseases, including atopic dermatitis. Cutaneous application of SpA increased serum levels of IL-18 and IgE. These results indicate that local accumulation of IL-18 triggers systemic IgE responses without exposure to antigen.

Animals↗

PubMed2002

Critical roles of myeloid differentiation factor 88-dependent proinflammatory cytokine release in early phase clearance of Listeria monocytogenes in mice.

Listeria monocytogenes (LM), a facultative intracellular Gram-positive bacterium, often causes lethal infection of the host. In this study we investigated the molecular mechanism underlying LM eradication in the early phase of infection. Upon infection with LM, both IL-12 and IL-18 were produced, and then they synergistically induced IFN-gamma production, leading to normal LM clearance in the host. IFN-gamma knockout (KO) mice were highly susceptible to LM infection. IL-12/IL-18 double knockout mice were also highly susceptible. Their susceptibility was less than that of IFN-gamma KO mice, but more than that of single IL-12 or IL-18 KO mice. Mice deficient in myeloid differentiation factor 88 (MyD88), an essential adaptor molecule used by signal transduction pathways of all members of the Toll-like receptor (TLR) family, showed an inability to produce IL-12 and IFN-gamma following LM infection and were most susceptible to LM. Furthermore, MyD88-deficient, but not IFN-gamma-deficient, Kupffer cells could not produce TNF-alpha in response to LM in vitro, indicating the importance of MyD88-dependent TNF-alpha production for host defense. As TLR2 KO, but not TLR4 KO, mice showed partial impairment in their capacity to produce IL-12, IFN-gamma, and TNF-alpha, TLR2 activation partly contributed to the induction of IL-12-mediated IFN-gamma production. These results indicated a critical role for TLRs/MyD88-dependent IL-12/TNF-alpha production and for IL-12- and IL-18-mediated IFN-gamma production in early phase clearance of LM.

Adaptor Proteins, Signal Transducing↗

PubMedDate not supplied

Efficacy of nutritional therapy for perforating and non-perforating Crohn's disease.

BACKGROUND/AIMS: Enteral nutrition is the currently established primary therapy for Crohn's disease in Japan. We examined the effects of postoperative nutritional therapy in patients with perforating type and non-perforating type Crohn's disease. METHODOLOGY: We retrospectively reviewed the records for 218 patients who underwent surgical interventions for Crohn's disease in our hospital between January 1, 1974 and September 30, 2001. They were divided into four groups: 92 patients in the non-perforating type (NP type) + Elemental Diet (ED) group had received ED therapy and nutritional education, 22 patients in the NP type + NoED group had not received ED therapy or nutritional education, 88 patients in the perforating type (P type) + ED group and 16 patients in P type + NoED group. We evaluated the incidence of reoperation rate for each group. RESULTS: Patients with a postoperative ED therapy demonstrated a significant decrease in the incidence of second resection. The incidence of second resection in the NP type + ED group was significantly lower than that of the other groups. The NP type + NoED group and the P type + ED group followed similar courses. CONCLUSIONS: In patients with Crohn's disease postoperative ED therapy and nutritional education is effective in reducing the incidence of second resection. It appears that postoperative ED therapy and nutritional education is more important in patients with P type Crohn's disease.

Adolescent↗