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Kazuhiro Yamada

Publications and source records attributed to Kazuhiro Yamada.

47 records · Page 3Linked to original sources
PubMed2003

[Analysis of factors affecting the course of renal disease progression in patients with established renal insufficiency].

All renal diseases ultimately progress to end-stage renal disease after renal dysfunction develops except for acute renal failure or rapidly progressive glomerulonephritis. However, renal function can be preserved for long periods in patients with mild renal insufficiency. We examined the factors affecting the progression of renal disease in patients with established renal insufficiency. We enrolled 38 patients with renal insufficiency diagnosed at the first visit and who were followed up for at least 3 years. We retrospectively recorded all information relating to serum creatinine and blood pressure levels during the follow-up periods. The patients were categorized as group A(n = 11), long-term renal survivors(at least 8 years), group B(n = 22), short-term renal survivors(3 to 8 years) and others(n = 5). Basal renal diseases were variable, and included IgA nephropathy, membranous nephropathy, focal segmental glomerulosclerosis, hypertensive glomerulosclerosis, tubulo-interstitial disease and lupus nephritis. Except for the degree of urinary occult blood, no other clinical data obtained at the first visit differed between groups A and B. Overall blood pressure levels throughout the entire clinical course also did not differ between the two groups. However, mean blood pressure levels before serum creatinine had reached the level of 2.0 mg/dl were significantly lower in group A compared with group B (96 +/- 7.8 vs. 103 +/- 6.3 mmHg, p < 0.05). We considered that the serum creatinine level of the so-called "point of no return" might be 2.0 mg/dl. In conclusion, blood pressure should be strictly controlled before serum creatinine levels reach 2.0 mg/dl.

Adult↗
PubMed2003

[Two cases of interstitial nephritis with primary Sjögren's syndrome successfully treated by steroid therapy].

We have experienced two cases of interstitial nephritis with Sjögren's syndrome successfully treated by steroid therapy. Case 1. A 50-year-old woman was admitted because of rash and arthralgia of the limb. Although her renal function was normal, serum IgG was extremely high and gallium-67 scintigrams indicated abnormal uptake in both kidneys with swelling on CT scans. Renal biopsy specimens showed a patchy dense interstitial infiltration of lymphocytes, monocytes and partly plasma cells with tubular cell atrophy. To suppress an excessive immune reaction, oral prednisolone was administrated at a dose of 30 mg/day. Six weeks after inception of the therapy, re-biopsy specimens showed a decrease in interstitial infiltration, particularly plasma cells, and interstitial fibrosis did not progress. After 8 weeks, the serum IgG level was normalized. Case 2. A 57-year-old woman was found to have renal involvement(serum creatinine level: 2.2 mg/dl) and anemia. Clinical findings suggested primary Sjögren's syndrome with renal tubular acidosis. Renal biopsy specimens showed a moderate to severe interstitial infiltration of inflammatory cells. After inception of steroid therapy(prednisolone 40 mg/day), renal involvement and renal anemia gradually improved. The renal function has been kept stable(serum creatinine level: 1.5 mg/dl) for 9 years by low-dose steroid therapy. These two cases suggest that steroid therapy plays two important roles: controlling of the acute immune reaction that causes renal fibrosis to progress in case 1, and long-term preservation of the renal function by the continuous use of low-doses in case 2.

Anti-Inflammatory Agents↗
PubMed2002

Lactate utilization as an energy substrate in ischemic preconditioned rat brain slices.

We examined the utilization of lactate as an energy substrate in ischemic preconditioned slices obtained from the rat brain left hemisphere, of which the contralateral middle cerebral artery was occluded 48 h before the slice preparation. The levels of high-energy phosphates in the brain slices were measured using 31P NMR with a time resolution of 4 min at 25 degrees C. When iodoacetic acid-pretreated brain slices were further treated with fluorocitrate, a glial toxin, for 2 h (neuron-rich slices), the recovery of the phosphocreatine (PCr) level in artificial cerebrospinal fluid (ACSF) containing lactate after high-K+ stimulation was completely abolished in intact slices, whereas the PCr level in ischemic preconditioned slices well recovered in otherwise similar conditions. These results indicated that neurons, when preconditioned with ischemia, acquire the ability to utilize lactate as an energy substrate. In parallel experiments, we recorded population excitatory postsynaptic potentials and spikes from granule cells in hippocampal slices. Population spikes of intact slices in ACSF containing lactate were completely abolished in 30 min, but those of the ischemic preconditioned slices were maintained well over 50%. These results show that ischemic preconditioning may induce certain systematic changes in neurons, such as the expression of lactate transporters and/or the activation of lactate dehydrogenase.

Animals↗
PubMed2002

Head and neck cancer antigens recognized by the humoral immune system.

Head and neck cancer in advanced stages are difficult to treat. Therefore, development of new treatment modalities and preventive measures are required. We now report the identification of human head and neck cancer antigens recognized by the humoral immune system. We used the serological analysis of recombinant cDNA expression libraries (SEREX) approach. cDNA libraries from cell lines of squamous cell carcinoma of head and neck (SCCHN) and a normal testicle tissue were screened using sera from six allogeneic SCCHN patients. Total 28 positive clones belonging to 19 different genes were identified, including 12 known genes and 7 unknown ones. Expression analysis on 13 normal tissues and 13 cancer tissues using reverse transcription-PCR (RT-PCR) revealed eight ubiquitously expressed genes, nine of which were expressed preferentially in cancer tissues and two cancer/testis antigens. These antigens we defined may be pertinent candidate antigens for future cancer-diagnosis and related immunotherapy.

Antibody Formation↗
PubMed2002

Crystal structure of the RuvA-RuvB complex: a structural basis for the Holliday junction migrating motor machinery.

We present the X-ray structure of the RuvA-RuvB complex, which plays a crucial role in ATP-dependent branch migration. Two RuvA tetramers form the symmetric and closed octameric shell, where four RuvA domain IIIs spring out in the two opposite directions to be individually caught by a single RuvB. The binding of domain III deforms the protruding beta hairpin in the N-terminal domain of RuvB and thereby appears to induce a functional and less symmetric RuvB hexameric ring. The model of the RuvA-RuvB junction DNA ternary complex, constructed by fitting the X-ray structure into the averaged electron microscopic images of the RuvA-RuvB junction, appears to be more compatible with the branch migration mode of a fixed RuvA-RuvB interaction than with a rotational interaction mode.

Adenosine Triphosphatases↗
PubMed2002

Postoperative mandibular stability after orthognathic surgery in patients with mandibular protrusion and mandibular deviation.

Skeletal stability and temporomandibular joint (TMJ) signs and symptoms were analyzed in 23 patients in whom mandibular protrusion and mandibular deviation had been corrected using bilateral sagittal split ramus osteotomy (BSSRO group, n = 10) and unilateral SSRO and intraoral vertical ramus osteotomy (USSRO+IVRO group, n = 13). Miniplate fixation was used in SSRO but no fixation was used in IVRO. The ratio of condylar bony change was 30.4% (7/23) and all condylar bony changes were seen on the deviated side. All preoperative signs and symptoms of TMJ disorders (4/13 patients in the USSRO+IVRO group and 2/10 patients in the BSSRO group) disappeared after surgery. Comparing the USSRO+IVRO group and the BSSRO group, in patients without condylar bony change, the mandible in both groups was stable anteriorly and horizontally after surgery, even though there was a larger horizontal mandibular movement in the USSRO+IVRO group during surgery. Comparing patients with condylar bony change versus no condylar bony change in the USSRO+IVRO group, postoperative horizontal mandibular displacement was significantly larger in the condylar bony change group than in the no condylar bony change group. These results support the idea that USSRO+IVRO can be useful in correcting mandibular deviation as well as improving signs and symptoms of TMJ disorders. However, it also seems important to be aware of the possibility of horizontal mandibular relapse in patients with condylar bony change.

Adolescent↗
PubMed2002

[Remarkable rightward shift of the mediastinum during a urological operation in the left kidney position--a case report].

Mediastinal rightward shift without involving cardiovascular collapse and dyspnea occurred after a left nephroureterectomy. An 86-year-old female (height, 142 cm; weight, 53 kg) with ureteral cancer was scheduled for an elective nephroureterectomy. Preanesthetic electrocardiogram revealed supraventricular premature contractions and sinus tachycardia (116 beats.min-1) and preanesthetic chest X-ray film revealed cardio-thoracic ratio of 60% and pleural adhesion of the right apex of the lung. Anesthesia was maintained with a combination of inhalation anesthetics (oxygen, nitrous oxide and sevoflurane) and thoracic epidural lidocaine. Artificial ventilation was used during the anesthesia. The operation was uneventful. A chest radiograph taken at the end of the operation demonstrated a large mass-like shadow in the right field of the lung. However, dyspnea or cardiovascular collapse was not observed. The vesicular sounds were auscultated in the left lung field. Results of arterial blood gas analysis during spontaneous respiration were within normal ranges. A CT scanning of the chest showed that the great vessel and the heart had been in the right thoracic cavity. Therefore, we considered that a rightward mediastinal shift had occured during the operation.

Aged↗
PubMed2002

Relationship between bilateral condylar bone change and mandibular morphology: a study using morphometry.

This study was undertaken to evaluate the relationship between bilateral condylar bone change (BCBC) and mandibular morphology. Thirty Japanese women with BCBC as diagnosed from computed tomographic scans were compared to 2 control groups: 26 Class I and 25 Class II Japanese women. All cephalograms were traced and scanned, and 14 homologous landmarks were digitized. Coordinates were used for cephalometric analysis, Procrustes analysis, Euclidean distance matrix analysis (EDMA), and thin-plate spline (TPS) analysis. Comparison of the cephalometric data for the BCBC and Class I groups revealed significant shrinkage in the condylar process and ramus height, in addition to a shorter body length. The centroid size showed that BCBC mean geometric forms were smaller than those of Class I and Class II. The landmark morphology of the BCBC group differed from both Class I and Class II, as shown by the residuals (P < .001). EDMA showed expansion of infradentale-pogonion (9.9%) and along the anterior slope height of the condyle (28.6%), while the posterior slope height decreased (21.6%). The vertical ramus height (gonioncondylion) also decreased by 11.8% in comparison to Class I. Compared to Class II, BCBC ramus height was shorter by 8.9%, condylar width decreased 13.7%, and the posterior condylar slope was 22% shorter. TPS analysis showed increased antegonial notching, a vertically expanded symphysis, and a collapsed and more horizontal condyle in the BCBC group. The combination of the above methods was very helpful in assessing mandibular morphology and showed that BCBC might be related not only to changes in the condyle, but may dictate changes in the rest of the mandible as well.

Adolescent↗
PubMedDate not supplied

"Point of no return (PNR)" in progressive IgA nephropathy: significance of blood pressure and proteinuria management up to PNR.

BACKGROUND: Based on observations of the clinical course in patients with IgA nephropathy (IgAN), D'Amico et al proposed the concept of the "point of no return (PNR)", after which progression to end-stage renal disease (ESRD) becomes inevitable. They reported that the approximate PNR is serum creatinine (sCr) 3.0 mg/dL. METHODS: To confirm the PNR and to clarify the factors affecting renal function deterioration in IgAN patients, we analyzed the sequential data of those with 1.2 or= 102 mmHg and/or urinary protein (UP) score >or= 2.0 with sCr up to 2.0 mg/dL was significantly poor. Multivariate analysis using the Cox's proportional hazards model, identified only MBP and UP during the course until sCr reached 2.0 mg/dl as independent prognostic factors for ESRD, having hazard ratios of 2.56 (per 10 mmHg; 95% confidence interval (95% CI) 1.08-6.05) and 4.37 (per 0.5 point; 95% CI 1.36-14.1), respectively. CONCLUSIONS: We confirmed PNR as a sCr level of 2.0 mg/dL (equivalent to estimated glomerular filtration rate (GFR) of 30-35 mL/min/1.73m2) during the course of IgAN in Japan. Proper management of both BP and UP until sCr has reached PNR is essential to arrest the progression to ESRD in IgAN.

Adult↗