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Yoshinobu Sumiyama

Publications and source records attributed to Yoshinobu Sumiyama.

At least 19 recordsLinked to original sources
PubMed2006

Tumor viability using real-time spectral images.

PURPOSE: We observed real-time spectral images using line-scan imaging spectrography in order to evaluate tumor viability. METHODS: Japanese albino rabbits, which underwent the implantation of VX2 tumor strain, were used as subcutaneous tumor models (n = 54). Photodynamic therapy (PDT) consisted of semiconductor laser irradiation of the tumorous lesion. The experimental groups consisted of a PDT group (n = 15) and a non-PDT group (control group, n = 15). The spectral images taken by a CCD camera underwent computer processing. Next, the spectrum of the tumorous lesion was observed and the peak spectrum value was measured. RESULTS: Two peaks (545 and 575 nm) corresponding to the absorbance spectrum of oxygenated hemoglobin (oxyHgb) were observed in the untreated area. In the treated area, however, they disappeared and a different peak (560 nm) corresponding to the absorbance spectrum of deoxygenated hemoglobin was observed. PDT induced ischemic tissues and the cells could be confirmed in real time in vivo in monochrome and color images reflecting the oxyHgb amount. A histopathological examination and phosphotungstic acid hematoxylin staining demonstrated diffuse fibrin accumulation in the microvessels, while proliferating cell nuclear antigen staining showed a reduced nuclear stainability. CONCLUSIONS: These results demonstrated that the real-time spectral images showed the actual histological conditions such as a blocked tumor blood flow and reduced tumor viability.

Animals↗
PubMed2006

Efficacy of bacteriophage therapy against gut-derived sepsis caused by Pseudomonas aeruginosa in mice.

We evaluated the efficacy of bacteriophage (phage) therapy by using a murine model of gut-derived sepsis caused by Pseudomonas aeruginosa that closely resembles the clinical pathophysiology of septicemia in humans. Oral administration of a newly isolated lytic phage strain (KPP10) significantly protected mice against mortality (survival rates, 66.7% for the phage-treated group versus 0% for the saline-treated control group; P<0.01). Mice treated with phage also had lower numbers of viable P. aeruginosa cells in their blood, liver, and spleen. The levels of inflammatory cytokines (tumor necrosis factor alpha TNF-alpha, interleukin-1beta [IL-1beta], and IL-6) in blood and liver were significantly lower in phage-treated mice than in phage-untreated mice. The number of viable P. aeruginosa cells in fecal matter in the gastrointestinal tract was significantly lower in phage-treated mice than in the saline-treated control mice. We also studied the efficacy of phage treatment for intraperitoneal infection caused by P. aeruginosa and found that phage treatment significantly improved the survival of mice, but only under limited experimental conditions. In conclusion, our findings suggest that oral administration of phage may be effective against gut-derived sepsis caused by P. aeruginosa.

Administration, Oral↗
PubMed2006

Single case of renal cell carcinoma and endocrine pancreatic head cancer occurring with von Hippel-Lindau disease.

Von Hippel-Lindau (VHL) disease is an autosomal dominant genetic disease in which various neoplastic lesions occur in multiple organs. Reported here is a case of VHL disease with concurrent renal cell carcinoma and endocrine pancreatic cancer. The patient was a 43-year old woman. On this occasion, the patient had sought treatment from her local physician, complaining chiefly of yellowing of the skin and bulbar conjunctiva. Abdominal ultrasound and computed tomography scans revealed a mass in the right kidney and a mass in the pancreatic head. Peripheral blood genetic analysis revealed an Arg/stop heteroconjugative mutation in codon 113 in exon 1 of the VHL gene on the short arm of chromosome 3 (p25-26). After various tests were performed, the patient was diagnosed with right renal cell carcinoma, malignant tumor of the pancreatic head, and multiple pancreatic cysts accompanying von Hippel-Lindau disease. Right nephrectomy and pancreatoduodenectomy were performed. Based on the histopathological results, the patient was diagnosed with right renal cell carcinoma and highly differentiated endocrine pancreatic cancer. Immunohistologically, a large number of atypical cells were found to be positive for both anti-chromogranin and anti-synaptophysin antibodies in the endocrine tumor. Immunostaining for each type of gut hormone was also performed, but all results were negative. Based on the above findings, nonfunctioning, highly differentiating endocrine cancer was diagnosed. This is the first confirmed case of renal cell carcinoma and endocrine pancreatic cancer occurring concurrently with VHL. This is an important case, so it is presented here along with a short discussion of the literature.

Adult↗
PubMed2006

Questionnaire on perioperative antibiotic therapy in 2003: postoperative prophylaxis.

We distributed a questionnaire to institutions accredited by the Japan Surgical Society asking about the use of antibiotics in digestive tract surgery in Japan in 2003, and compared the results with those of a similar questionnaire distributed in 1993. The period of antibiotic administration for esophageal resection was at least 6 days in 64.9% of the 1993 questionnaire responses, but less than 4 days in 60.4% of the present questionnaire responses. For distal gastrectomy, antibiotics were given for 5 days postoperatively at 53.0% of the responding institutions in the 1993 survey, but for only 3 days, at 72.4%, in the present survey. An oral antibiotic was given as part of antibacterial colon preparation before colon resection at 70% or more of the institutions in the 1993 survey, while no antibiotic colon preparation was given at 80% of the institutions in the present survey. The period of antibiotic administration for laparoscopic cholecystectomy was at least 4 days in 72% of the institutions in the 1993 survey, but this decreased remarkably to fewer than 2 days at 80.8% of the institutions in the current survey. There were no differences in the selection of antibiotics between the two surveys. The period of antibiotic administration has decreased remarkably in the last decade.

Anti-Bacterial Agents↗
PubMed2006

Creating a manual for proper hand hygiene and its clinical effects.

PURPOSE: To prevent cross-infections, we created a manual for the treatment of infectious wounds that clarifies when to wash one's hands and when to wear gloves. METHODS: Six patients with widespread infectious wounds caused by methicillin-resistant Staphylococcus aureus (MRSA) were treated. The bacterial count on the hands of the staff was calculated. We then compared the number of patients with MRSA isolated, and typed the MRSA isolates using pulsed-field gel electrophoresis (PFGE). RESULTS: The pathogenic bacterial count among hospital staff before treatment/before hand hygiene was 8.2 x 10 colony-forming units (cfu)/hand, which were not detected before treatment/after hand hygiene. The pathogenic bacterial count on the hands before hand hygiene/after treatment climbed to 9.1 x 10(5) cfu/hand, and after treatment/after hand hygiene decreased to 0.38 cfu/hand. The number of patients with MRSA isolates before this protocol was 15/402 (3.7%), but that level significantly decreased to 5/411 (1.2%) after implementation of the manual. There were 13 strains of type F by PFGE before the manual was adopted, but five strains of MRSA isolated after the present manual was enforced were all observed to have different migration patterns. CONCLUSION: A hand hygiene manual is effective for decreasing the rate of cross-infection.

Anti-Infective Agents, Local↗
PubMed2006

[A case of advanced gastric cancer--efficacy of combination therapy of doxifluridine and weekly paclitaxel].

A 65-year-old man underwent distal gastrectomy for advanced gastric cancer. Histological examination revealed that a lymph node metastasis extended to the para-aortic nodes. After operation, he was treated with TS-1 as first-line chemotherapy. After 10 months of the first-line chemotherapy, the lymph node swelling increased in size, and new lesions were detected. Then, the patient was treated by combination therapy of doxifluridine and weekly paclitaxel. Weekly paclitaxel administration (PTX 80 mg/m(2), 2 consecutive weeks, 1 week break) and oral administration of doxifluridine (600 mg/m(2), 14 consecutive days) were performed as the second-line chemotherapy. After 2 courses, abdominal CT scan showed a remarkable reduction of the para-aortic lymph nodes. The second-line chemotherapy was continued until the 7th course, then stopped without progression of the disease, and the patient maintained good quality of life. PTX/5'-DFUR combination therapy was thought to be an effective chemotherapy for advanced gastric cancer.

Adenocarcinoma↗
PubMed2005

Drug susceptibility of isolates from severe postoperative intraperitoneal infections causing multiple organ failure.

PURPOSE: To select the most appropriate antibiotic regimens for life-threatening postoperative infections, we obtained isolates from patients with severe postoperative infections over a 12-year-period, and examined their drug susceptibility. METHODS: The subjects of this study were 55 patients with multiple organ failure (MOF) caused by postoperative infection. RESULTS: All strains of Methicillin-resistant Staphylococcus aureus (MRSA) were susceptible to Vancomycin (VCM) and Teicoplanin (TEIC). Only 0.3% of all the Pseudomonas aeruginosa strains were resistant to Imipenem (IPM), but 53.6% of the strains from the severe infections were resistant to IPM. On the other hand, there were few P. aeruginosa strains resistant to Meropenem (MEPM), Ceftazidime (CAZ), Ciprofloxacin (CPFX), and Pazufloxacin (PZFX), even among strains isolated from severe infections. The resistant rate of Bacteroides fragilis to Clindamycin (CLDM) was 35.9%, but there were strains resistant to IPM and Panipenem. CONCLUSION: These findings suggest that VCM or TEIC are most appropriate for severe abdominal abscess caused by MRSA, whereas MEPM, CAZ, CPFX, and PZFX are more effective against P. aeruginosa infections. The only antibiotic effective against B. fragilis infections in this study was IPM.

Abdominal Abscess↗
PubMed2005

[A case of resectable solitary liver metastasis from breast cancer].

We report a case of resectable solitary liver metastasis from breast cancer. A 53-year-old woman underwent a pectoral muscle-preserving mastectomy for T1 N0M0 (Stage I) left breast cancer in May 2000. Histopathologic diagnosis was medullary carcinoma. Thereafter, the patient was followed up with adjuvant chemotherapy. A solitary tumor in the right lobe of the liver at S6 was found 10 months after mastectomy by ultrasonography. With a diagnosis of liver metastasis from breast cancer, right hepatectomy was performed in May 2001. At present, she remains disease free for 4 years after hepatectomy. We think that a surgical procedure for liver metastasis from breast cancer, if possible, is beneficial in prolonged survival.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2004

Role of macrophages in a mouse model of postoperative MRSA enteritis.

BACKGROUND: We have established a mouse model for fatal postoperative enteritis due to Staphylococcus aureus to analyze mechanisms of bacterial translocation and determine reasons for the lethality of this infection. In the present study the role of macrophages was ascertained in protection against S. aureus induced enteritis. MATERIALS AND METHODS: Mice were pretreated with cyclophosphamide (CY), an immunosuppressant, and then infected directly into the jejunum with methicillin-resistant S. aureus (MRSA) isolated from a patient. In other groups of mice liposome-encapsulated dichloromethylene diphosphate (Cl2MDP) was administered to deplete macrophages in vivo. Other experimental groups received lipoteichoic acid (LTA), which was used to inhibit the ability of macrophages to bind MRSA, and additionally, to analyze dependence of bacterial clearance on the macrophage scavenger receptor. The ability of macrophages to bind MRSA was compared with survival rates in this mouse model of fatal postoperative enteritis. RESULTS: Injection of liposome-encapsulated Cl2MDP decreased survival rate of mice infected intraintestinally with MRSA in a dose-dependent manner. Cyclophosphamide also decreased survival rate of MRSA-infected mice and was found to correlate with its ability to decrease the number of macrophages in the spleen. Intravenous LTA administration did not affect total splenocyte numbers or the number of splenic macrophages but decreased the ability of macrophages to bind MRSA and adversely affected survival of mice infected with MRSA. CONCLUSIONS: Macrophages play a critical role in protection against MRSA administered directly into the jejunum. LTA recognition sites (probably type A scavenger receptors) on macrophages are required for binding and phagocytosing MRSA.

Animals↗
PubMed2004

Current pancreatogastrointestinal anastomotic methods: results of a Japanese survey of 3109 patients.

BACKGROUND: Pancreatogastrointestinal anastomosis is the most important anastomotic method of reconstructing the digestive tract following pancreaticoduodenectomy. METHODS: We therefore conducted a survey on pancreatogastrointestinal anastomosis at the 28th Japan Pancreatic Surgery Club in 2001. RESULTS: Results revealed that of the methods of pancreatogastrointestinal anastomosis, pancreatojejunostomy (82.9%) was overwhelmingly more popular than pancreatogastrostomy (17.1%). Anastomotic leakage occurred in 12.8% of cases, and 13.0% of these patients died. The incidence of anastomotic leakage was 11.0% with pancreatogastrostomy, and 13.3% with pancreatojejunostomy. There was no significant difference in the development of anastomotic leakage among the anastomotic organ used with the pancreas, the pancreas resection method, and the pancreatic juice drainage method. Investigation of intra-abdominal hemorrhage and abscess, which are serious complications that result from anastomotic leakage, revealed that intra-abdominal hemorrhage occurred in 1.1% of all cases, and intra-abdominal abscess was seen in 3.3% of all cases. However, there were no significant differences between pancreatogastrostomy and pancreatojejunostomy with respect to incidence rates of intra-abdominal hemorrhage and abscess or mortality. CONCLUSIONS: The method of pancreatogastrointestinal anastomosis should be chosen according to each individual case.

Adolescent↗
PubMed2004

Recovery of the susceptibility of isolated bacterium achieved by giving long-established antibiotics as prophylaxis against postoperative infections.

PURPOSE: To evaluate the effectiveness of operative antibiotic therapy we changed the antibiotics and examined the susceptibility of the postoperative infection. METHODS: We studied 4 593 patients who underwent gastrointestinal surgery during the last 12.5 years, and examined the changes in intraoperative antibiotics, the return of bacteria isolated from infectious sites, the trends in frequency of Methicillin-resistant Staphylococcus aureus (MRSA) isolation, and changes in the antibiotic susceptibility of Pseudomonas aeruginosa and Bacterioides fragilis. We changed the antibiotics to Cefazolin (CEZ) for upper gastrointestinal tract surgery and cholecystectomy, and to Cefotiam (CTM) for colonic, liver, and pancreatic surgery. We also reduced the period of drug administration. RESULTS: The rate of MRSA infections decreased, the rate of P. aeruginosa infections was always under 20% and the rate of B. fragilis infections increased. After the guidelines of drug susceptibility were prepared, the minimum inhibitory concentrations (MICs) of Cefsulodin (CFS) and Piperacillin (PIPC) for P. aeruginosa and of Latamoxef (LMOX) and PIPC for B. fragilis, decreased. CONCLUSION: The use of antibiotics considered comparatively old for the prophylaxis of postoperative infection prevented the emergence of MRSA-like resistant strains, influenced changes in Gram-negative bacteria drug susceptibility, and led to an overall reduction in multiple drug resistance.

Anti-Bacterial Agents↗
PubMed2004

Influence of various antimicrobial agents on the intestinal flora in an intestinal MRSA-carrying rat model.

Using an intestinal methicillin-resistant Staphylococcus aureus (MRSA)-carrying rat model, we compared the influence of piperacillin (PIPC) on the intestinal flora to those of cefazolin (CEZ), cefmetazole (CMZ), and flomoxef (FMOX). The number of MRSA did not increase after PIPC and CEZ administrations compared with the nontreated group. However, it significantly increased in the cases of FMOX and CMZ administration (P < 0.01). In the FMOX- and CMZ-treated groups, the intestinal flora was severely disrupted and the recovery of the number of Escherichia coli and Bacteroides spp. cells was delayed. On the other hand, in the PIPC- and CEZ-treated groups, the rapid recovery of bacteria that composed the intestinal flora was observed. The C(max)/MIC(50) and C(trough)/MIC(50) ratios in E. coli and Bacteroides spp. in the case of FMOX and CMZ were relatively higher than those in the case of the PIPC- and CEZ-treated groups.

Animals↗
PubMed2004

[Hand disinfection and cross-infection countermeasures].

Methicillin-resistant Staphylococcus aureus (MRSA) causes droplet infection and contact infection, and therefore when taking measures against cross-infection it is preferable to take even stricter action than for other bacteria. The basic policies for preventing cross-infection require measures that assume the presence of MRSA until the results of bacterial testing are reported if discharge from the patient is noted. To prevent cross-infection, it is not sufficient simply to enforce strict disinfecting of the hands. It is necessary to establish a manual of measures to deal with situations at different posts.

Cross Infection↗
PubMed2004

Thymoma.

Explore the source record for details and available documents.

Humans↗
PubMed2003

Selective use of transthyretin and retinol-binding protein as markers in the postoperative assessment of protein nutritional status.

We evaluated several markers to judge the postoperative state of protein nutriture in eight patients following surgery for cancer. Seven patients had a good prognosis and had no evidence of infections or other complications. Following surgery, all of the patients showed a shift toward abnormal values for the serum concentrations of albumin, transthyretin (TT), retinol-binding protein (RBP), and the amino acid (AA) ratio of nonessential to essential amino acids. In patients without complications, the AA ratio returned to normal first. When blood specimens were collected at 7-day intervals, concentrations of RBP and TT were revealed to be decreased and recovered at the same time, or TT was recovered after RBP was normalized. RBP and TT were usually abnormal until the AA ratio became normal. Although albumin moved toward normal concentrations after RBP and TT, the albumin concentrations in some patients were slightly above the lower reference value, whereas RBP and TT were significantly below their lower reference limits. In these patients, assessments over the next 7-14 days showed persistently low values for albumin, TT, and RBP. We recommend the selective use of TT and RBP for the postoperative assessment of protein nutriture in surgical patients.

Aged↗