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C Yamazaki

Publications and source records attributed to C Yamazaki.

16 recordsLinked to original sources
PubMed1992

[Evaluation of secondary hyperparathyroidism in the patients undergoing hemodialysis--focused on parathyroid hormone assay system].

We evaluated the degree of secondary hyperparathyroidism (SHPT) in the patients undergoing long-term hemodialysis treatment. Most patients showed improvement of SHPT by administration of the active vitamin D3 analogue. However, some patients developed overt SHPT even under intensive treatment. Pulse therapy with large dose of vitamin D3 for those who suffered from overt SHPT was an effective treatment modality at the initial stage, however, hypercalcemia which developed in the majority of the patients at the later stage of this treatment became an obstacle for the continuation of this treatment. Therefore, early detection of the hypersecretion state of parathyroid hormone (PTH) as well as earlier initiation of intensive therapy are important factors in preventing overt SHPT. Establishment of a suitable assay system for early detection of SHPT is an important task and the high sensitivity-PTH assay system may be the most desirable. Though diabetic patients were not likely to develop overt SHPT, this system could detect even the mild chronological increase of serum PTH level in diabetic patients. On the other hand, relatively earlier initiation of vitamin D3 therapy to the predialysis patients from the conservative treatment stage caused aggravation of deterioration of renal function. Therefore, we should be prudent to initiate vitamin D3 therapy on predialysis patients suffering from renal failure. Strict management of the patients by vitamin D3 as well as calcium supplement therapy along with evaluation of the serum PTH level is still an important measure to avoid overt SHPT.

Cholecalciferol↗
PubMed1992

Hepatitis C virus infection in medical personnel after needlestick accident.

Hepatitis C virus infections in medical personnel after needlestick accidents have been documented generally by detection of seroconversion to a hepatitis C virus nonstructural region antigen, c100-3 (a marker of infection). We tested for hepatitis C virus core-derived antibodies and genomic RNA in addition to c100-3 antibody in 159 cases of needlestick exposure that did not involve patients positive for HBsAg. Of these we found 68 cases with index patients positive for both hepatitis C virus RNA and antibodies and members negative for antibodies to HCV core or c100-3 before the needlestick accidents. Seven of these medical personnel became infected with hepatitis C virus after the accidents. Their hepatitis was generally subclinical or self-limited and transient, except for one patient in whom liver enzyme elevation persisted along with the antibodies. In our study, the risk of hepatitis C virus transmission from a single needlestick accident with hepatitis C virus RNA-positive blood was 10%, considerably higher than the 4% estimated in a previous study. We found that donor blood with antibody to an hepatitis C virus core-derived peptide with enzyme-linked immunosorbent assay optical densities greater than 2.0 carried a significant risk of transmitting hepatitis C virus to needlestick victims. No hepatitis C virus seroconversions occurred in medical personnel exposed to hepatitis C virus antibody-negative or hepatitis C virus RNA-negative blood; however, one such exposure resulted in a very mild non-A, non-B, non-C hepatitis.

Health Personnel↗
PubMed1992

[Pharmacokinetics and clinical effect of recombinant human erythropoietin on the anemia of predialysis patients].

The marvelous effect of recombinant human erythropoietin (EPOCH) on the anemia of the patients suffering from chronic renal failure had been already reported even in the predialysis patients. However, the influence on residual renal function as well as pharmacokinetics of EPOCH in predialysis patients was not clarified yet. Therefore, we made a clinical study of EPOCH in 10 predialysis patients to investigate the clinical effect as well as pharmacokinetics. EPOCH was administered intravenously once a week with the dosage of 3,000-9,000 IU for 8 weeks. All patients showed prominent improvement of anemia. Though no patient show serious adverse effect, two patients showed controllable hypertension accompanying with the increase of hematocrit. Meanwhile, the speed of the deterioration of residual renal function obtained from the regression line by reciprocal of the serum creatinine was not aggravated by the correction of anemia. Pharmacokinetic study revealed that the halflife of EPOCH was extended compared to normal but the degree of extension was same as that of in dialyzed patients. The plasma concentration-time curves showed the pattern of monoexponential disappearance and the area under the curve (AUC 0 to 48 hr.) showed dose-response increase. However, both parameters mentioned above as well as systemic clearance rate did not show any change between those of on day 0 and on day 56. These results no long-term accumulation of EPOCH, though the level of intrinsic erythropoietin was decreased after EPOCH treatment. Thus, the beneficial effect of EPOCH on the correction of anemia was revealed even in the predialysis patients without affecting on residual renal function.

Adult↗
PubMed1991

Utility of venography in shunt surgery on hemodialyzed patients.

Fifty-eight examples of upper extremity venography in 40 patients undergoing or about to undergo hemodialysis and 18 normal subjects were evaluated. In the normal subjects, tools and conditions of venography were investigated. It was considered necessary to maintain 30 degrees flexion of the cubital joint and supination of the antebrachium and use a 35 x 43 cm film to facilitate upper extremity venous system interpretation. In the patient group, standard venography was compared with shunt-delineating venography (called shuntgraphy) as to advantages and drawbacks. Venography proved to be of excellent use in shunt constructive and reconstructive surgeries in that it provided information supplementary to that obtained in shuntgraphy, or even more valuable information.

Adult↗
PubMed1990

Side effects and pharmacokinetics of nonionic iodinated contrast medium in hemodialyzed patients.

We conducted contrast CT scanning on 22 dialysis patients using the same method as usually applied to cases with normal renal function and studied the incidences and types of side effects and the pharmacological kinetics of non-ionic iodine contrast medium (Iopamiron 370, 100 ml). During the followup period (five days at most), we found localized urtication as a side effect in only one case (4.5%). Therefore we speculate that non-ionic contrast medium is a safe agent in dialysis patients, as long as it is cautiously used. After contrast medium injection, we conducted dialysis twice, which definitely decreased total blood iodine content. The extraction ratio at first dialysis was particularly high (73% on average). We recognized a statistically positive correlation between this extraction ratio and dialyzer size. Although two cases studied proved the notable acceleration of vicarious excretion in dialysis patients, this acceleration appeared only with high total blood iodine content. This phenomenon was considered mainly due to excretion from the hepatobiliary tract. Vicarious excretion appeared relatively soon after contrast medium injection (within a few hours), but showed a slower decreasing tendency.

Adult↗