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Hajime Takahashi

Publications and source records attributed to Hajime Takahashi.

At least 19 recordsLinked to original sources
PubMed2006

Development of a quantitative real-time PCR method to enumerate total bacterial counts in ready-to-eat fruits and vegetables.

A newly developed real-time PCR assay rapidly quantifies the total bacterial numbers in contaminated ready-to-eat vegetables and fruits compared with the standard plate count method. Primers targeting the rpoB gene, which encodes for the beta subunit of the bacterial RNA polymerase and which is common to most bacterial species, was used instead of the 16S rRNA gene, which has multiple copies and varies among bacterial species. A primer pair specific for rpoB was confirmed to amplify rpoB in a wide range of bacterial species after we assessed 49 strains isolated from five kinds of fruits and vegetables. We purchased fruits and vegetables from retail shops and enumerated the bacteria associated with them by use of real-time PCR and compared this to the number found by the culture method. We found a high correlation between the threshold PCR cycle number when compared with the plate count culture number. The real-time PCR assay developed in this study can enumerate the dominant bacterial species in ready-to-eat fruits and vegetables.

Bacteria↗
PubMed2005

Influence of cure of Helicobacter pylori infection on gastric acidity and gastroesophageal reflux: study by 24-h pH monitoring in patients with gastric or duodenal ulcer.

BACKGROUND: Whether or not the eradication of Helicobacter pylori is a risk factor for reflux esophagitis (RE) is a question at issue. To find an answer, it is necessary to clarify the influence of H. pylori eradication on the mechanism of RE. METHODS: The authors investigated the influence of H. pylori eradication on gastric acidity and gastroesophageal reflux in ten gastric ulcer (GU) patients and ten duodenal ulcer (DU) patients by 24-h simultaneous determination of pH in the stomach and esophagus. RESULTS: Though the results indicated enhanced gastric acidity in GU patients at night after H. pylori eradication, no such influence was observed in DU patients. No significant changes in gastroesophageal reflux occurred in GU or DU patients before and after H. pylori eradication. RE after H. pylori eradication occurred in only one patient, with GU. This patient had several risk factors for RE, such as obesity, male sex, and dietary habits to add to the increase in gastric acidity at night that occurred after H. pylori eradication. No increase in gastroesophageal reflux occurred in any DU patients or in the other GU patients that demonstrated enhanced gastric acidity at night after H. pylori eradication. CONCLUSIONS: The cure of H. pylori infection does not, by itself, cause RE in patients who have few other risk factors for RE.

Adolescent↗
PubMed2005

Development of a quantitative real-time polymerase chain reaction targeted to the toxR for detection of Vibrio vulnificus.

The TaqMan assay, a quantitative real-time polymerase chain reaction (PCR), was developed to target the ToxR gene (toxR) of Vibrio vulnificus. The toxR of V. vulnificus was cloned and sequenced. Based on these results, we designed specific primers and a probe for use in the quantitative PCR assay. Twenty-nine strains of V. vulnificus that were obtained from various sources produced a single PCR product. The amount of final amplification product and threshold cycle number were the same among the strains. We used the method to detect V. vulnificus in seawater and oyster samples. We developed standard curves to quantitate V. vulnificus numbers using the PCR from seawater and oyster samples. The standard curves were not different from that of the pure culture of V. vulnificus. We found the assay was very sensitive detecting as few as 10 microbes per milliliter of seawater and oyster homogenate. Moreover, we evaluated the TaqMan assay to detect V. vulnificus in seawater samples. The numbers of V. vulnificus counted by the TaqMan assay were similar to those by a culture method in almost samples. The TaqMan assay was performed within 2 h compared to days using the culture method. The results indicate the TaqMan assay method used in this study was rapid, effective and quantitative for monitoring V. vulnificus contamination in seawater and seafoods such as oysters.

Animals↗
PubMed2005

Phorbol myristate acetate induces neutrophil death through activation of p38 mitogen-activated protein kinase that requires endogenous reactive oxygen species other than HOCl.

Stimulation of normal mouse neutrophils with phorbol 12-myristate 13-acetate resulted in an acceleration of chromatin condensation and phosphatidylserine externalization that was not associated with caspase-3 activation. Caspase-independent death was completely inhibited by GF109203X and SB202190, specific inhibitors for protein kinase C and p38 mitogen-activated protein kinase respectively. Activation of p38 mitogen-activated protein kinase was completely suppressed by GF109203X, indicating that this enzyme is regulated by protein kinase C. On the other hand, cell death was abolished in NADPH oxidase-deficient neutrophils lacking superoxide production. Of note, p38 mitogen-activated protein kinase was activated by phorbol 12-myristate 13-acetate in normal and myeloperoxidase-deficient neutrophils lacking production of HOCl, whereas no activation was observed in NADPH oxidase-deficient neutrophils. These results strongly suggest that activation of p38 mitogen-activated protein kinase is regulated by endogenously generated superoxide or its metabolites other than HOCl, a critical regulator of inducer-stimulated death of neutrophils.

Animals↗
PubMed2005

Incidence of Listeria monocytogenes in raw seafood products in Japanese retail stores.

The incidence of Listeria monocytogenes in raw fish, shellfish, and fish roe was investigated in seafood products collected from randomly selected retail stores in and around Tokyo, Japan. Of the 10 samples of 208 examined found positive for L. monocytogenes by mini-VIDAS LMO, seven were fish roe (cod, salmon) and three were minced tuna. Three serotypes (1/2a, 1/2b, 3b) were detected among the isolated strains; serotype 1/2a was predominant (8 of 10).

Animals↗
PubMed2005

Development of a quantitative real-time PCR method for estimation of the total number of Vibrio parahaemolyticus in contaminated shellfish and seawater.

A real-time PCR method targeting the toxR gene of Vibrio parahaemolyticus was developed to quantify the number of V. parahaemolyticus cells, including those of both the hemolysin-producing and nonproducing strains. The specificity of the primer and probe set was confirmed using 25 strains of V. parahaemolyticus and 30 strains of other microbial species. We determined the threshold cycle number using the real-time PCR and the number of V. parahaemolyticus cells by plate count using serially diluted pure culture and developed a standard curve for quantification. Standard curves for V. parahaemolyticus in seawater and seafood were established using artificially inoculated samples. The threshold cycle number and the number of V. parahaemolyticus cells were correlated with 10(1) to 10(7) CFU/ml in pure culture, seawater, and shellfish homogenate. The real-time PCR method developed in this study was compared with the most-probable-number method in seafood samples that were naturally contaminated. The differences in the number of V. parahaemolyticus cells as determined by the culture method and the PCR method were less than 10-fold.

Animals↗
PubMed2005

[Interstitial pneumonia and nephritis with Sjögren's syndrome: successful treatment with corticosteroid therapy].

A Sixty eight-year-old man complained of shortness of breath on exercise since the spring of 2001. An abnormal lung shadow was pointed out on chest X-ray and progression of renal dysfunction and high gamma globulinemia were detected out on blood examination. He was admitted to the Department of Respiratory Disease in our hospital in March 2003, because of bilateral lower lung interstitial shadow, severe anemia (Hb 7.9 g/dl), and renal dysfunction (S-Cr 1.9 mg/dl). He was found to have hypergammaglobulinemia (IgG 2,997 mg/dl), positive RO/SS-A antigen, high serum KL-6 level (2,050 U/ml), and increased urinary excretion of beta2-microglobulin (beta2MG). Both Gum test and Schirmer test results were positive. Lip biopsy showed cell infiltration to the salivary glands and he was diagnosed as having Sjogren's syndrome. Renal biopsy showed diffuse interstitial cell infiltration and a Trans Bronchoscopic Lung Biopsy (TBLB) showed fibrotic thickness and lymphocyte infiltration in the alveolar septum. Accordingly, he was diagnosed as having Sjögren's syndrome complicated with both interstitial nephritis and interstitial pneumonitis. He was treated by high-dose corticosteroid therapy and anticoagulant heparin. His laboratory data showed that both serum KL-6 and urinary beta2MG were reduced. Chest CT showed remarkable improvement of the interstitial shadow. A second renal biopsy performed at ten weeks after the beginning of treatment showed remarkable improvement of the interstitial cell infiltration. This is a rare case of Sjögren's syndrome complicated with interstitial nephritis and interstitial pneumonitis, treated successfully with high-dose corticosteroid therapy. Both complications showed immediate improvement with high-dose corticosteroid therapy, suggesting that early steroid therapy is effective for both complications.

Aged↗
PubMed2004

Novel archaeal alanine:glyoxylate aminotransferase from Thermococcus litoralis.

A novel alanine:glyoxylate aminotransferase was found in a hyperthermophilic archaeon, Thermococcus litoralis. The amino acid sequence of the enzyme did not show a similarity to any alanine:glyoxylate aminotransferases reported so far. Homologues of the enzyme appear to be present in almost all hyperthermophilic archaea whose whole genomes have been sequenced.

Amino Acid Sequence↗
PubMed2004

Detection of Leuconostoc strains at a meat processing plant using polymerase chain reaction.

To simplify the labor-intensive conventional routine testing of samples to detect Leuconostoc at a meat processing plant, we developed polymerase chain reaction (PCR) primers specific for Leuconostoc from 16S rRNA gene sequences. These primers did not detect other common lactic acid bacteria such as Lactobacillus plantarum, Lact. sake, Lact. fermentum, Lact. acidophilus and Weissella viridescens. PCR with this primer detected all Leuconostoc species tested (Leu. mesenteroides subsp. mesenteroides, Leu. pseudomesenteroides, Leu. carnosum, Leu. lactic, Leu. citreum, Leu. amelibiosum, Leu. gelidum), except for Leu. fallax, and no other lactic acid bacteria on agarose gel electrophoresis. The method could identify areas contaminated with Leuconostoc in a large-scale industrial meat processing plant. Of 69 samples analyzed, 34 were positive for Leuconostoc according to the conventional culture method (isolation of LAB producing dextran) and PCR, whereas 29 were negative according to both. Six samples were culture-negative but positive by PCR. No false negative results were generated by PCR. The method is rapid and simple, is useful for routinely monitoring areas contaminated with Leuconostoc in meat processing plants, and could help to prevent the spoilage of meat products.

DNA Primers↗
PubMed2004

Direct detection and identification of lactic acid bacteria in a food processing plant and in meat products using denaturing gradient gel electrophoresis.

We established a novel system using denaturing gradient gel electrophoresis (DGGE) to quickly identify bacteria known to be responsible for spoilage in meat processing plants and meat products. We extracted bacterial DNA from swabbed samples at various locations in the plant and from meat products and performed PCR amplification, targeting 16S rDNA from the dominant organisms. The amplification products were subjected to DGGE, and the contaminating bacteria in the meat products and the plant were analyzed. This analysis indicated that lactic acid bacteria and spoilage-causing bacteria are widely distributed within the meat processing plant. We developed molecular size markers to identify the dominant organisms obtained from the plant and meat products. The establishment of the present method allows quick and simple identification of bacteria causing the possible deterioration of products and contamination and thus permits constant monitoring of any harmful bacteria within meat processing plants.

Animals↗
PubMed2003

Placental villotrophoblastic pulmonary emboli after elective abortion: immunohistochemical diagnosis and comparison with ten control cases.

Although pulmonary trophoblastic embolism is now considered a physiologic phenomenon of normal pregnancy, this phenomenon has not been demonstrated in a living asymptomatic patient. Recently we encountered a 26-year-old woman suspected of pulmonary embolism of villotrophoblastic tissues after therapeutic abortion. Although her serum beta-hCG was low, a computed tomography scan showed multiple nodules in both lungs. Histological examination of a nodule in a lung-biopsy specimen showed granulation tissue surrounding a hemorrhagic mass within which were structures resembling degenerating chorionic villi. Immunohistochemical study on the patient's lung nodule, and a second endometrial-curettage specimen, six control endometrial and tubal specimens containing degenerating chorionic villi, and four endometrial specimens containing viable chorionic villi were performed. The patterns of immunostaining for cytokeratin, human chorionic gonadotropin, human placental lactogen, placental alkaline phosphatase, and inhibin-alpha of the chorionic villus-like structures in the lung nodule were almost identical to those in the degenerating chorionic villi, but different from those of viable villi. This is a unique case of embolism of chorionic villi and trophoblast to the lung in a living patient after therapeutic abortion.

Abortion, Induced↗
PubMed2003

Cloning and sequencing of the histidine decarboxylase genes of gram-negative, histamine-producing bacteria and their application in detection and identification of these organisms in fish.

The use of molecular tools for early and rapid detection of gram-negative histamine-producing bacteria is important for preventing the accumulation of histamine in fish products. To date, no molecular detection or identification system for gram-negative histamine-producing bacteria has been developed. A molecular method that allows the rapid detection of gram-negative histamine producers by PCR and simultaneous differentiation by single-strand conformation polymorphism (SSCP) analysis using the amplification product of the histidine decarboxylase genes (hdc) was developed. A collection of 37 strains of histamine-producing bacteria (8 reference strains from culture collections and 29 isolates from fish) and 470 strains of non-histamine-producing bacteria isolated from fish were tested. Histamine production of bacteria was determined by paper chromatography and confirmed by high-performance liquid chromatography. Among 37 strains of histamine-producing bacteria, all histidine-decarboxylating gram-negative bacteria produced a PCR product, except for a strain of Citrobacter braakii. In contrast, none of the non-histamine-producing strains (470 strains) produced an amplification product. Specificity of the amplification was further confirmed by sequencing the 0.7-kbp amplification product. A phylogenetic tree of the isolates constructed using newly determined sequences of partial hdc was similar to the phylogenetic tree generated from 16S ribosomal DNA sequences. Histamine accumulation occurred when PCR amplification of hdc was positive in all of fish samples tested and the presence of powerful histamine producers was confirmed by subsequent SSCP identification. The potential application of the PCR-SSCP method as a rapid monitoring tool is discussed.

Amino Acid Sequence↗
PubMed2002

High-transport membrane is a risk factor for encapsulating peritoneal sclerosis developing after long-term continuous ambulatory peritoneal dialysis treatment.

Increased peritoneal function has been suggested to be a risk factor for developing encapsulating peritoneal sclerosis (EPS); however, clinical evidence is scarce. The present study aimed to clarify the specific character of peritoneal function in patients who developed EPS after withdrawal from peritoneal dialysis (PD). We studied 12 patients who developed EPS after PD withdrawal [(EPS group) mean PD duration: 109 months; mean period of EPS development: 7.0 months after withdrawal] and 128 patients who did not develop EPS (non EPS group). All 140 patients were withdrawn from continuous ambulatory peritoneal dialysis (CAPD) and were observed for the following 24 months. Based on the records of the annual peritoneal equilibration tests (PETs), we analyzed (1) the patients' dialysate-to-plasma (D/P) creatinine at various durations on PD, and (2) the accumulative appearance incidence of high-transport (HT) state of peritoneal membrane. The mean D/P creatinine in EPS group was significantly higher than that in the non EPS group in the course of PD from the 6th to the 10th year. The accumulative incidence of HT was significantly higher in the EPS group than in the non EPS group, indicating early development of HT membrane in EPS group. Early development of increased D/P creatinine, classified as HT state, was observed during certain periods on PD in patients who developed EPS after PD withdrawal. That finding may indicate that HT state of peritoneal membrane is an early marker for EPS, and that the PET is useful to detect patients at high risk of EPS.

Adult↗
PubMed2002

Fifteen cases of encapsulating peritoneal sclerosis related to peritoneal dialysis: a single-center experience in Japan.

To evaluate the incidence and characteristics of encapsulating peritoneal sclerosis (EPS), we analyzed 111 patients who had been transferred to hemodialysis and had been periodically monitored using the peritoneal equilibration test. Encapsulating peritoneal sclerosis was diagnosed in 11 patients. All patients had high-transport peritoneum, and 10 patients had been treated with continuous ambulatory peritoneal dialysis (CAPD) for more than 72 months. Incidence of EPS increased according to prolongation of CAPD. To evaluate outcome, we analyzed 15 cases of EPS. All patients were treated with total parenteral nutrition (TPN). Five patients improved with TPN alone. However, the remaining 10 patients showed deterioration. Of those 10, 4 patients died. They had not been treated with corticosteroids (CSs). The remaining 6 patients were treated with CSs, but they did not improve. Those cases required surgical treatment. The postoperative course in 4 patients was satisfactory, but 2 patients died. In our center, the EPS survival rate was 60%. In patients treated with TPN alone, the remission rate was only 33.3%. Administration of CSs could not improve that rate. In 6 patients treated with surgery, the mortality rate was 33.3%. When EPS symptoms are not ameliorated by CS and TPN, surgical treatment should be considered. To prevent EPS, high-risk patients who have more than 72 months on CAPD and who have a high-transport peritoneum should discontinue CAPD.

Biological Transport↗
PubMed2002

Risk factors and preventive measures for encapsulating peritoneal sclerosis--Jikei experience 2002.

A growing incidence of encapsulating peritoneal sclerosis (EPS) has been reported recently in Japan, and it is now urgent to establish preventive measures against EPS development. In the present paper, we describe our observational results regarding the risk of EPS development and the characteristic features of patients with EPS, in terms of peritoneal morphology and peritoneal function as determined by peritoneal equilibration test. The ongoing working protocol for EPS prevention at Jikei University Hospital is also discussed. Our findings have revealed that long-term continuous ambulatory peritoneal dialysis (CAPD) is a risk factor for EPS development after transfer to hemodialysis from peritoneal dialysis (PD), and that, in most patients with EPS, peritoneal function is characterized by a longstanding high-transport state. The striking alterations in peritoneal morphology between patients with EPS and those with simple long-term CAPD hyperplasia include, in EPS patients, a prominent thickening of the collagenous layer of the peritoneum with neoangiogenesis and myofibroblastic transformation. Based on our findings, we established a withdrawal protocol for long-term CAPD patients, with the goal of preventing EPS. Those who have been on PD treatment for more than 72 months with high-transport state are candidates for withdrawal from PD, with performance of peritoneal lavage thereafter for a certain period of time. The clinical benefit of post-PD lavage has not yet been determined; however, the maneuver could be precluded in patients at low risk of EPS, because it was found that some patients can recover to average transport state during the period of PD withdrawal. Patients who remain high transporters with inflammatory reaction might require pharmacologic intervention, including prednisolone therapy. Further observations are required to validate our approach.

Adult↗
PubMed2002

[Effect of angiotensin II receptor antagonist (losartan) on renal function, serum potassium and blood pressure in patients with advanced renal failure: differences between patients with a serum creatinine (SCr) level higher than 3 mg/dl and those with a lower SCr level].

The administration of angiotensin II receptor antagonist(AIIA) to patients with advanced chronic renal failure(CRF) is not actively recommended. This study was performed to verify the appropriateness of this situation and to determine if there are any substantial differences between patients with a serum creatinine(SCr) level higher than 3 mg/dl and those with a lower SCr level in terms of the clinical effects such as renal function, serum potassium level and systemic blood pressure(BP) after the administration of AIIA. Sixteen patients with advanced CRF who were admitted to the out-patient clinic in Jikei University Hospital(1998/1-1999/12) were enrolled(average age: 65 years, underlying renal disease: diabetic nephropathy 6, CGN 5, and other 1). They had never been administered AIIA before. The patients were classified into two groups in accordance with their level of SCr: group A(SCr lower than 3.0 mg/dl; n = 11), and Group B(SCr higher than 3.0 mg/dl; n = 5). Losartan(50 mg/day) administration was started in order to examine parameters such as the SCr, potassium, BP at the out-patient clinic, and urinary protein excretion at the 0, 1, 3, 6, 9, and 12 month time points. Although the 1/SCr values provided negative slopes with time in both groups, no significant difference was found between the two slopes. There were no changes in the serum potassium levels or urinary protein excretion during the study period in either group, and no statistical difference was found between the two groups. Although the serum potassium level exceeded 5.5 mEq/l in two patients each in both groups, the level was controlled by diet therapy with restricted potassium. BP was reduced significantly in both groups during the study period, and no statistical difference in BP reduction was observed between the two groups. In conclusion, the results indicate there were no differences in the effect on renal function, serum potassium levels or systemic BP between the patients with a SCr level higher than 3.0 mg/dl and those with a lower level. The results also support the notion that patients with advanced renal dysfunction are not precluded from AIIA administration.

Aged↗