Search PubMed⌕ Search

Biomedical subjects

H Noto

Publications and source records attributed to H Noto.

At least 37 records · Page 2Linked to original sources
PubMed1996

Inhibition of contractile tension by capsaicin in isolated rat papillary muscle.

1. We examined effects of capsaicin (10(-9) - 10(-5) M), a pungent agent extracted from red pepper, on the contractile tension of rat ventricular papillary muscles stimulated at various cycle lengths (0.2, 0.5, 1, 2 and 5 sec). 2. Capsaicin produced a marked concentration-dependent decrease in the amplitude, the rate of rise (dp/dt) and the rate of relaxation (dr/dt) of the tension. 3. However, the half relaxation time and the time to peak tension of the tension were slightly affected by the agent. 4. The negative inotropic effect of capsaicin was stimulus cycle length (CL) dependent. In particular, IC50 (50% inhibitive concentration) of the agent in the amplitude of the tension was stimulus CL dependent. That is, the values of IC50 were around 10(-7) M at longer CLs (1, 2 and 5 sec), and the value of IC50 at CL 0.2 sec was 4 x 10(-6) M. 5. These capsaicin-induced negative inotropic effects were reversible. Other studies from our laboratory show that the negative inotropic effects may be largely due to a decrease in Ca2+ current.

Animals↗
PubMed1996

Capsaicin does not inhibit the intracellular calcium handling process in rat ventricular papillary muscle.

1. We studied the effects of capsaicin, a pungent agent extracted from red pepper, on rested-state contraction (RSC) of isolated rat ventricular papillary muscles. 2. The RSC was induced by stimulation, after a rest interval of 5 sec to 10 min, after the twitch tension of the muscle preparation stimulated at the regular stimulus frequency of cycle lengths of 5, 1 or 0.2 sec attained the steady state. 3. Drug effects were evaluated on the RSC in the presence of capsaicin 10(-5) M, caffeine 10(-2) M or ryanodine 10(-7) M, respectively. 4. All drugs inhibited the RSC but to different degrees. Ryanodine was the most effective in inhibiting RSC, followed by caffeine and capsaicin, in that order. However, the inhibitory mode varied, depending on the drugs. 5. These findings suggest that capsaicin may not inhibit the function of intracellular Ca2+ store in rat cardiac muscle.

Alkaloids↗
PubMed1995

Severe hyponatremia and hyperkalemia induced by trimethoprim-sulfamethoxazole in patients with Pneumocystis carinii pneumonia.

An antimicrobial agent trimethoprim-sulfamethoxazole (Tmp-Smx) does not usually cause electrolyte disturbances at regular doses, and few cases of Tmp-Smx-induced electrolyte imbalance have been reported in the English-language literature to date. Recently, however, we treated two patients with Pneumocystis carinii pneumonia who developed severe hyponatremia and hyperkalemia on administration of high-dose Tmp-Smx. These electrolyte disturbances were attributable to the direct effect of Tmp-Smx on the renal distal tubules, were reversible, and corrected by infusion of a sodium-enriched and potassium-free liquid. Therefore, it is suggested that even after electrolyte disturbances have occurred, high-dose Tmp-Smx therapy may be continued for severe infectious diseases under appropriate electrolyte correction.

Humans↗
PubMed1995

[Cavernostomy and muscle plombage with the pedicled latissimus dorsi and serratus anterior flap for recurrent large bullae with infection: a case report].

A 70-year-old male, who suffered from infection by MRSA and Aspergillus of the recurrent large bullae, was operated on cavernostomy for space sterilization. About three months later he underwent muscle plombage with the pedicled latissimus dorsi and serratus anterior flap. These muscles are ideal to place in open wound in the thorax because of the following reasons: These have the ability to eliminate local infection, a sufficient length and volume to obliterate an open cavity. And transposition of these muscles cause minimal functional upper extremity disability. Therefore, we considered that this technic was useful for the case of an infectious intrathoracic cavity with many bronchial fistulas.

Aged↗
PubMed1993

Analysis of prognostic factors in patients with resected peripheral T1 adenocarcinoma of the lung.

Prognostic factors in patients with surgically-treated peripheral T1 (< or = 3 cm in greatest diameter) adenocarcinoma of the lung were analyzed in 45 cases. Statistical difference in survival was observed between stages I + II and III + IV (p < 0.05). However, neither sex, age, location of tumor, histological subtype, histological grade, tumor ploidy, nor presence of central fibrosis was of prognostic determinance. Our results suggest that only clinical stage is of prognostic importance in surgically-treated peripheral T1 adenocarcinoma of the lung.

Adenocarcinoma↗
PubMed1993

[Case report of congenital bronchial cyst in the subsuperior segment of the right lung].

A fifty-five-year-old man revealed abnormal shadow on chest X-P. Congenital Bronchial Cyst (CBC) is believed to be caused by the abnormal budding process during the early development of the foregut and after born result in formation of noninfected cysts in the lung. In this case, CBC was lined by columnarciliated epithelium and contained cartilages and bronchial mucous glands in their wall. They were located along the tracheobronchial tree and cystgraphy presented dumbbell-like change of cysts that were seen during the development stage. These findings support the past reports radiographically that CBC may result from occlusion of the proximal side of bronchus during the early development by unknown mechanism.

Bronchogenic Cyst↗
PubMed1992

Modulation of the spinobulbospinal micturition reflex pathway in cats.

Micturition, which is mediated by a spinobulbospinal reflex pathway, can be modulated by various spinal and supraspinal mechanisms. This study examined modulation of the micturition reflex in decerebrate unanesthetized cats. Electrical stimulation of the pontine micturition center (PMC) elicited two types of bladder responses: small-amplitude short-duration responses due to direct activation of the bulbospinal pathway (PS-direct contractions) and large-amplitude long-duration reflex responses induced by PS-direct contractions but maintained by afferent feedback (PS-reflex contractions). Rectal and vaginal-cervical stimulation inhibited the PS-direct contractions, indicating inhibition of the descending or efferent limb of the micturition pathway. Stimulation of the central end of a transected S2 ventral root elicited recurrent inhibition of PS-reflex contractions but not of PS-direct contractions, indicating that recurrent inhibition does not directly affect the descending pathway. Continuous electrical stimulation (20 Hz) of the PMC decreased (53 +/- 21%) bladder capacity, presumably by affecting transmission in the pons or ascending input to the pons. Thus the micturition reflex could be modulated at several sites: the pons, the ascending or descending pathways, or spinal interneuronal sites.

Afferent Pathways↗
PubMed1992

The effect of alpha-2 agonists and antagonists on the upper urinary tract of the rat.

We examined the effect of the selective alpha-2 agonist dexmedetomidine and antagonist atipamizole on the upper urinary tract, renal pelvic pressure and ureteral peristalsis. Experiments were performed on twelve Sprague-Dawley female rats weighing 275-323 grams, with administration of urethane (1.2 micrograms/kg). Ventilatory support was provided through a tracheotomy. A continuous normal saline infusion was maintained through the left iliac vein at a rate of 2.5 ml/hr. Arterial pressure was measured at the left iliac artery, which was cannulated with a PE-100 tube connected to a pressure transducer. A mid-line incision was then made from the xyphoid to the symphysis to expose the left kidney, both ureters, and the bladder. The bladder was intubated and drained to avoid bladder pressure increase. Measurements of urine output rate were made from the right ureter and renal pelvic or ureteral pressure was measured using a nephrostomy placed into the pelvis. A ureterostomy was produced by introducing another catheter, into the upper segment of the left ureter for ureteral pressure measurements. The rats were divided into two groups as follows: 1) dexmedetomidine group (n = 6); injected intravenously with 2 micrograms/kg of dexmedetomidine dissolved in 0.5 ml saline. 2) atipamizole group (n = 6); injected intravenously with 2 micrograms/kg of atipamizole dissolved in 0.5 ml saline. Ureteral peristaltic frequency, baseline pressure, and contraction amplitude were compared before, after, and between the bolus injections of 2 micrograms/kg dexmedetomidine (n = 6) or 2 micrograms/kg atipamizole (n = 6) in 0.5 ml saline. The results showed that dexmedetomidine at 2 micrograms/kg produced a significant decrease in arterial pressure and an increase in urine output from 1.2 + 0.8 to 3.6 + 1.2 ml/min. There was no effect on the baseline pelvic pressure of 6.8 + 1.2 cmH2O or amplitude of the renal pelvic contractions: 3.5 + 0.6 cmH2O. The frequency of pelvic contractions was reduced from 0.37 + 0.03 to 0.27 + 0.02 Hz. Atipamizole at 2 micrograms/kg produced a significant reduction in urine flow rate of 1.1 + 0.8 to 0.6 + 0.2 ml/min. Atipamizole also showed no significant effects on baseline pelvic pressure or frequency, but increased the amplitude of pelvic contractions from control values of 3.0 + 0.9 to 3.4 + 0.9 cmH2O. Dexmedetomidine reduced both the baseline ureteral pressure of 8.5 + 2.4 and peristaltic contraction pressure of 11.5 + 2.3 cmH2O in 4/6 rats. Atipamizole reduced base-line ureteral pressure and increased peristaltic rate.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenergic alpha-Agonists↗
PubMed1992

[Effect of terazosin on lower urinary tract function in the male decerebrate dog].

The effect of terazosin on the lower urinary tract function was studied by combined recording of bladder and urethral pressures and external sphincter electromyogram in 8 male decerebrate dogs. Reflex micturitions were induced by bladder filling before and after terazosin. The statistical analysis was carried out on the urodynamic parameters. During the collecting phase, terazosin at doses of 10, 30 and 100 micrograms/kg produced a significant decrease in maximum urethral pressure in the dose dependent manner. Threshold pressure was significantly shown to decrease at doses of 30 and 100 micrograms/kg. In the urodynamic parameters of the emptying phase there was a significant decrease in maximum contraction pressure at 10 and 30 micrograms/kg, and in voided volume at 100 micrograms/kg. Terazosin seems to facilitate an initiation of the bladder contraction with a decrease in threshold pressure. In concludes that alpha 1 adrenergic activity seems to take an important role for the maintenance of the urethral pressure and to control the initiation of bladder contraction in modulation with threshold pressure.

Animals↗
PubMed1992

Effect of methylene blue on the vesicourethral function in the rats.

The bladder and urethral activities during the rhythmic bladder contractions were evaluated before and after the intraarterial administration of methylene blue, which prevents the activation of soluble guanylate cyclase. The methylene blue produced an increase in the bladder activity and a decrease in the urethral smooth muscle relaxant response induced with bladder contraction. The L-arginine/nitric oxide pathway seems to modulate the vesicourethral function.

Anesthesia↗
PubMed1992

[Vesical ultrasonography and internal examination of female patients with urethral syndrome].

Transabdominal ultrasonography of the bladder and internal examination were performed in 80 female patients without pyuria. They were divided into 3 groups: urethral syndrome with trigonitis (49 cases), asymptomatic trigonitis (16 cases) and normal bladder (15 cases) by cystoscopy. Ultrasonography of trigonitis with or without symptoms showed focal dilation of the submucosal low echo zone and mucosal irregularity around the bladder neck. On the sagittal view, the thicknesses from the surface of mucosa to that of muscle layer within 2 cm from the bladder neck were 4 +/- 1 mm (mean +/- standard deviation) in the group with urethral syndrome and in that with asymptomatic trigonitis, and 3 +/- 1 mm in the normal bladder group. Mucosa of the trigonitis with or without symptom is patients with significantly thicker than that of those with normal bladder (p less than 0.01). On internal examination, tenderness at the upper frontal wall of the vagina was present in 10 of 11 cases (91%) with urethral syndrome, in 2 of 8 cases (25%) with asymptomatic trigonitis and in one of 9 cases (11%) with normal bladder. There was a significant difference (p less than 0.005) between the degree of inflammation and the number of cases with tenderness at the frontal wall of the vagina. From these results, transabdominal ultrasonographic measurement of mucosal thickness around the bladder neck and internal examination for tenderness at the frontal wall of vagina are thought to be useful methods for diagnosis and follow-up of urethral syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[An approach to stoma-less continent urinary diversion by uretero-ileoceco-proctostomy (ileocecorectal bladder)].

The current practice of continent urinary diversion still places the patients under the restraint of the stoma and intermittent catheterization. To overcome these problems, we developed a new technique of urinary diversion of which continent is controlled by the anal sphincter. The isolated ileocecal segment is intussuscepted and interposed between the ureters and the rectum. The conjoined ureters are anastomosed to the stump of the ileal limb, and the antimesenteric portion of the cecal limb is joined to the anterior wall of the rectum. The surgical procedure is simpler than that of the continent reservoirs currently employed. The intussuscepted ileocecal segment prevents fecal reflux to the upper urinary tract and may also inhibit carcinogenesis at the uretero-intestinal junction. Additionally, the rectal capacity is augmented by the side to side anastomosis between the cecal limb and the rectum. Our preliminary experience in 10 cases were satisfactory with respect to voiding function, antireflux mechanism of the intussuscepted ileocecal segment and quality of life. The results will justify further trials with this stomaless continent urinary diversion for those in whom the urethra cannot be used.

Anal Canal↗
PubMed1992

[Comparative study on nephrotoxicity of ionic and non-ionic contrast agents for drip infused urography].

The effects on renal function of an ionic and hyperosmolaric contrast agent (diatrizoate) and a non-ionic and slightly hypertonic agent (iohexol) for drip infused urography were compared on 60 patients with normal renal function. Urine samples were collected before and 30 minutes after drip infusion of contrast agent, and analyzed for albumin (ALB), gamma-glutamyl transpeptidase (gamma-GTP), N-acetyl-beta-glucosaminidase (NAG), beta 2 microglobulin (beta 2MG) and creatinine (CRE). The urinary excretion of proteins and enzymes was compared with urinary CRE. gamma-GTP, NAG and beta 2MG increased significantly after infusion of diatrizoate. gamma-GTP and beta 2MG increased significantly after infusion of iohexol. Excretion of ALB, gamma-GTP, NAG and beta 2MG was significantly higher after infusion of diatrizoate than after iohexol. The urinary concentration of CRE was significantly lower after infusion of diatrizoate than after iohexol. The degree of renal damage after urography was no related to the appearance of allergy to the contrast agent or age of patient. Therefore, the non-ionic and slightly hyperosmolaric iohexol may be less toxic to the kidneys than the ionic and hypertonic diatrizoate. This nephrotoxicity after drip infused urography is thought to be related mainly to the osmolarity of contrast agent.

Adult↗
PubMed1992

[Effects of Tsumura Chorei-to and Tsumura Chorei-to-go-shimotsu-to on patients with urethral syndrome].

Tsumura Chorei-to or Tsumura Chorei-to-go-shimotsu-to, was administered to 71 female patients with urethral syndrome 2.5 g three times a day for four weeks. Total efficacy rate of Tsumura Chorei-to in 34 cases was 71%. Tsumura Chorei-to was effective against pollakisuria, miction pain or discomfort, sense of residual urine and lower abdominal discomfort. Total efficacy rate of Tsumura Chorei-to-go-shimotsu-to in 37 cases was 57%. Tsumura Chorei-to-go-shimotsu-to was effective against dysuria, sense of residual urine and lower abdominal discomfort. Uutoward effect rates of Tsumura Chorei-to and Tsumura Chorei-to-go-shimotsu-to were 6% and 14%, respectively. Many of the untoward effects of these two drugs were epigastral discomfort. These two drugs are thought to be effective on patients with urethral syndrome.

Adult↗