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Biomedical subjects

K Ido

Publications and source records attributed to K Ido.

At least 145 records · Page 8Linked to original sources

Age-related changes in the microvessels of the human stomach: an ultrastructural study.

The ultrastructure of microvessels in the gastric mucosa of patients with atrophic gastritis was investigated. In the gastric mucosa of atrophic gastritis, the endothelial cells of microvessels were irregularly swollen and subendothelial spaces were enlarged. The basement membrane underlying the endothelium was thickened. Degeneration of smooth-muscle cells was also evident in the media. These changes appear to correspond to sclerosis or aging of the microvessels. Such sclerotic changes in microvessels may initiate deterioration of the microenvironment in the gastric mucosa and may consequently affect metabolic activity of the gastric mucosal cells. Those sequences might induce degeneration or abnormal differentiation of mucosal cells. Such vascular changes may advance slowly and increase in intensity with advancing age. The final result would be the histologic changes associated with atrophic gastritis.

Aged↗

Histologic differentiation and motility of rat stomach.

An ultrastructural and immunohistochemical study was done to investigate the normal developmental process of rat gastric wall. Neuronal processes were observed on the external side of immature muscle cells on gestational day 15, and Auerbach's plexus was found on gestational day 18, after which neuronal elements extended just under the subepithelial area. Myofilaments appeared in undifferentiated mesenchyme cells on gestational day 15. On day 17, stomach was responsive to Ach stimulation. On the day after the initiation of gastric motility, gastric glands started to form on the mucosal surface. At the same developmental stage, some parts of the mucosal epithelium and the submucosal connective tissues were stained with antiserum against tenascin. Endocrine and parietal cells appeared in the mucosal epithelium on gestational day 19. Dense secretory granules on the apical surface of mucosal epithelium were increased between day 20 and 21. The cytoplasmic organelles gradually developed with advancing fetal age. We suggest that tenascin may play a role in gastric gland formation and that there are some relationships between gastric gland formation and gastric motility. We believe that the development of subepithelial tissues may be closely associated with epithelial growth.

Animals↗

Glass ceramic augmentation of the acetabulum. Total hip arthroplasties in 24 dogs.

Implants made of glass-ceramic containing apatite and wollastonite were used for reconstruction of large bone defects of the weight-bearing acetabulum in canine total hip arthroplasties. 24 dogs underwent replacements and were killed after 3, 6, and 12 months. The interface between the prosthesis and bone was examined radiographically, histologically, and mechanically. Bone bonding with the prosthesis occurred in all the implants. Glass ceramic containing apatite and wollastonite implants seem promising for use in total hip arthroplasty as filling materials for large defects in weight-bearing bone.

Acetabulum↗

Cementless total hip replacement. Bio-active glass ceramic coating studied in dogs.

We studied 2 types of a cementless total hip prosthesis in dogs. Both were coated with titanium plasma-spray. In both components, the pores in the deep layer of 1 group were further coated with apatite and wollastonite containing glass-ceramic (AW glass-ceramic). 50 dogs underwent unilateral total hip replacements, and were killed at 1, 3, or 6 months postoperatively. We evaluated the femoral and the acetabular components mechanically and histologically. At 1 month, the detaching load and bone ingrowth of the AW glass-ceramic-coated femoral and acetabular components were higher than those of the control implants. At 3 and 6 months there were no differences between the 2 types of components. Thus, AW glass-ceramic enhanced the early phase of cementless implant fixation.

Animals↗

Laparoscopic cholecystectomy: the Japanese experience.

We investigated the current status of laparoscopic cholecystectomy in Japan. A retrospective survey of laparoscopic cholecystectomy was performed involving 1989 patients from eight Japanese institutions. The preoperative work-up and the operative technique were largely identical to those in the United States. Conversion to open cholecystectomy was required in 54 patients (2.7%) because of unexpected intraoperative findings such as inflammation and adhesions in 40 patients (2.0%) and intraoperative complications in 14 patients (0.7%). There were no deaths, and postoperative complications occurred in 34 of 1935 patients (1.75%) in whom laparoscopic cholecystectomy was completed. Only 10 patients (0.51%) had serious complications (hemorrhage and bile duct injury, for example) that required laparotomy. The incidence of bile duct injury was 11 of 1989 (0.55%). We conclude that the adoption of laparoscopic cholecystectomy in Japan has been highly successful.

Cholecystectomy, Laparoscopic↗

Introduction of a "safety zone" for the safety of laparoscopic cholecystectomy.

Anatomic variations of the biliary tract were found in 18 cases of 600 patients (3.0%) undergoing laparoscopic cholecystectomy. All bile duct anomalies were confirmed preoperatively by endoscopic retrograde cholangiography. In every case, the cystic duct and cystic artery were exposed in a "safety zone" near the gallbladder neck in Calot's triangle. Laparoscopic cholecystectomy was successfully performed on all 18 cases. Intraoperative cholangiography clearly demonstrated the anatomic variations in all cases, unequivocally identified the cystic duct, and confirmed the absence of bile duct injury. Preoperative endoscopic retrograde cholangiography and intraoperative cholangiography, which have been performed routinely in all patients, improve the safety of laparoscopic cholecystectomy. Moreover, the observance of the essential rule of "keep operating in the safety zone" protects against inadvertent complications, especially against bile duct injury during laparoscopic cholecystectomy. Laparoscopic cholecystectomy was thus successfully performed on all 600 cases in the present series, except for three cases, which were converted to open surgery (conversion rates, 0.5%), because of pin-hole bleeding on the portal vein in our first case of 600, and severe adhesion in two (46th and 302nd) cases.

Bile Ducts↗

[Percutaneous transluminal angioplasty for stenotic dialysis arterio-venous fistulas].

From December 1982 to January 1991, we performed fistulography on 40 patients who complained functional failure of arterio-venous dialysis fistula. And percutaneous transluminal angioplasty (PTA) was attempted on 15 patients (19 times) who revealed marked fistula stenosis. Initial successful rate was 78.9% and patency rate was 56.2% in the first 6 months. (75% in the first 6 months when angioplasty was initially successful). We describe the method of fistulography and PTA for stenotic dialysis fistulas, and evaluate the usefulness of PTA. And also we introduce our attempts for improving the initial successful rate and patency rate. In conclusion, when dialysis arterio-venous fistula is stenotic but not occlusive, PTA should be considered first before surgical treatment is done.

Adult↗

Transcatheter hepatic arterial chemoembolization using epirubicin-lipiodol: experimental and pharmacological evaluation.

The experimental and pharmacological characteristics of various formulations of an anticancer agent (epirubicin, EPI) and lipiodol were evaluated in vitro and in vivo. Three forms of EPI-lipiodol, i.e., an oil-in-water type of emulsion (O/W type), a water-in-oil type of emulsion (W/O type), and a suspension (S type), were prepared and investigated for their stability. An O/W-type emulsion using a stock solution of Iopamidol as the solvent for EPI was the most stable form in the stationary state in vitro. In 16 patients with malignant liver tumors (14 hepatocellular carcinomas and 2 liver metastases), the three forms of EPI-lipiodol were injected into the proper hepatic artery. The plasma EPI level was monitored periodically and analyzed pharmacokinetically. No significant difference in the pharmacokinetics of EPI was detected among the O/W, W/O, and S types.

Aged↗

Spectral sensitivities for illusory contour perception: a manifold linkage of chromatic and achromatic cues with the generation of contours.

Using colored inducing patterns presented as increments upon a white uniform background, the increment thresholds needed for illusory contour perception were measured as a function of the wavelength of inducing pattern. The spectral sensitivity functions were obtained with varying adaptation level and stimulus configuration, high and low background illumination, and line-based and figure-based inducing patterns. The results showed a distinctive feature between the line-based and the figure-based illusory contours. The sensitivity functions for the line-based illusory contours showed the characteristics of non-opponent mechanisms and they were shape invariant with background intensity and spatial variables. On the other hand, the sensitivity functions for the figure-based illusory contours showed non-opponent nature for low background illumination but opponent nature for high background illumination. It is suggested that the generation of illusory contours involves concurrent processing of different cues of luminance and color, and that photopic adaptation level and stimulus configuration control the degree of the contributions of chromatic and achromatic mechanisms to contour formation.

Adaptation, Ocular↗

Prospective study of laparoscopic cholecystectomy in two hundred and fifty patients.

Two hundred and fifty consecutive patients (151 women, 99 men, age 49.3 years) with symptomatic gallstones as diagnosed on ultrasonography underwent elective laparoscopic cholecystectomy over a 12-month period. Preoperative intravenous cholangiography (IVC) and endoscopic retrograde cholangiography (ERC) were also performed in 203 and 200 patients, respectively. Laparoscopic cholecystectomy was successfully performed on 248 of the 250 patients (99.2%). Two patients required conversion to open cholecystectomy because of a pin hole injury to the portal vein in one case, and because of technical difficulties with the dissection due to severe adhesions in the other patient. Procedure time in the initial 100 cases decreased from an average of 216 minutes for the first ten cases to 87 minutes for the last 30 cases, including the time required for intraoperative cholangiography (IOC). Bile duct stones were found in 4 cases on IOC which were diagnosed by preoperative ultrasonography, IVC and ERC in 0, 2 and 3 cases respectively. An intraabdominal drain was inserted for two days in all cases. The mean hospital stay was 8.6 days (range 4 to 19 days) with no readmissions. No complications were seen at short-term follow-up one month after discharge. Although there was a significant learning period, the procedure was safe and effective and could be performed with minimal risk. The results show that physicians with experience in both endoscopy and laparoscopy are well qualified to perform laparoscopic cholecystectomy after appropriate training.

Cholangiography↗

Preliminary experience using laparoscopic transcystic cholangioscopy for treatment of common bile duct stones.

Laparoscopic transcystic cholangioscopy (LTC) in combination with electrohydraulic lithotripsy may be an alternative treatment to ERCP and sphincterotomy in patients with both gallbladder and common bile duct stones undergoing laparoscopic cholecystectomy. Preliminary experience using LTC lithotripsy in 13 cases is reported. In 12 cases the stones were pushed out into the duodenum using the tip of the cholangioscope, in 8 of them stone disintegration via LTC lithotripsy also being required. In the remaining case the cholangioscope could not be inserted into the common bile duct via the cystic duct due to complete cystic duct obstruction. The average hospital stay was 9 days (range 6-16) in patients with LTC/lithotripsy, which did not differ significantly from 8.4 days (range, 4-19) (n = 330) in the group undergoing laparoscopic cholecystectomy alone. The patients usually resumed normal activity the day after discharge. LTC lithotripsy has the advantages over endoscopic sphincterotomy of a shorter treatment and preservation of a normal functioning sphincter of Oddi. Further technical improvements, especially the development of a cholangioscope for this purpose, are urgently required.

Adult↗

[Laparoscopic cholecystectomy].

Two hundred and fifty consecutive patients with symptomatic gallstones underwent elective laparoscopic cholecystectomy over a ten month period. Out of 250 cases, 2 (0.8%) were converted to open cholecystectomy. One was due to bleeding, and the other being due to severe adhesion. The remaining 248 cases resulted in complete success without any complications or postoperative readmission. In this modality of laparoscopic cholecystectomy, there is an apparent learning experience which can be covered only by adequate training and experience. From an ethical point of view, however, training should not be undertaken at the expense of patients. With less experienced operators, the threshold of indication for laparoscopic cholecystectomy should be set high in order to secure the safety of the patients as well as the successful completion of the procedures.

Adult↗

[Fallopian tube recanalization with a catheter system--experience in the use of a balloon catheter].

Fallopian tube obstruction is one of the most difficult problems in the treatment of infertility. This report gives the results of a pilot study on the transcervical recanalization of the occlusive fallopian tube. Selective catheterization of the uterine cornu was applied through a balloon catheter, which was wedged at the internal uterine os. In 16 occlusive fallopian tubes of 11 cases, the catheterization procedure was attempted and accomplished with a 87.5% success rate. Recanalization was successful in 75.0% of the affected tubes. Subsequent pregnancy was confirmed in three cases. This convenient technique is safe and effective and it will be accepted as the first choice in the diagnosis and treatment of fallopian tube obstruction.

Adult↗

[Laparoscopic laser cholecystectomy: a prospective analysis of 70 initial cases].

Laparoscopic cholecystectomy using Nd-YAG laser was performed in 70 consecutive patients with preoperatively symptomatic gallstones. Sixty-eight patients had successful completion of the laparoscopic cholecystectomy. Mean hospital stay was 7.8 days (range: 4-12), and a diet as well as physical walking was tolerated in all 68 patients by the next day following the procedure. Mean operating time was 216 minutes in the initial 10 cases, which improved significantly to 87 minutes in the latest 28 cases. The difference of operative time did not influence any difference on the postoperative course. Nineteen of 68 patients (27.9%) required postoperative pain medication (pentazocine 15 mg, i.m.). Two patients required conversion to open cholecystectomy because of a pin hole injury on the portal vein by laser quartz in the first case, and difficult dissection due to severe adhesion in the 46th case. There is a definite learning curve in this new modality. Laparoscopic cholecystectomy is a safe and effective procedure, significantly improving the quality of life of the patients with gallstones.

Adult↗

Hyperreninemic hypoaldosteronism due to hepatocellular carcinoma metastatic to the adrenal gland.

Metastases to the adrenal glands are common in patients with cancer, but among those affected, hyperreninemic hypoaldosteronism is noted very rarely. A case of hyperreninemic hypoaldosteronism secondary to metastatic hepatocellular carcinoma is reported. Laboratory data revealed selective aldosterone deficiency with hyperreninemia. Biopsy documented replacement of the adrenal glands with metastatic hepatocellular carcinoma. A review of the literature disclosed that the present case was an extremely rare one of its kind.

Adrenal Gland Neoplasms↗

[Transcatheter arterial embolization for massive abdominal bleeding in post-pancreatoduodenectomy--first report].

Transcatheter arteria embolization (TAE) was carried out for 10 cases (14 times) with massive intra-abdominal bleeding after pancreatoduodenectomy (PD). The results obtained were as follows: 1. The ten patients (carcinoma of the pancreas head 4, carcinoma of the papilla Vater: 3, carcinoma of the bile duct: 2. leiomyosarcoma of the duodenum: 1) included eight men and two women aged 45 to 75, with an average age of 63.7. The time span before TAE was instituted averaged 20.8 days. 2. Infection due to leakage noted in all cases. 3. A good course was noted when manifestation of symptoms related to poor sutures or the onset of intra-abdominal bleeding after PD was delayed and the time from the onset of intra-abdominal bleeding to TAE was short. 4. Bleeding sites could be determined in all cases. Pseudoaneurysm accounted for five and extravasation accounted for nine of the total of 14 bleeding sites. The prognosis was apparently good in cases of pseudoaneurysm as compared with that in cases of extravasation. 5. Bleeding was controlled in all cases. 6. No complication due to TAE occurred. These results indicate the TAE is a safe and effective procedure for the control of massive intra-abdominal bleeding after PD.

Abdomen↗

[Magnetic resonance imaging of bladder tumors: superiority of serial "Fast SE" assisted by Gd-DTPA in tumor staging].

Eighteen cases with bladder tumors were examined by means of superconducting MRI. Sequences used were spin echo (TR/TE (msec) = 500/20 as T1WI (weighted image) and 1500/80 as T2WI) and serial "fast spin echo (fast SE)" pre/post Gd-DTPA administration. "Fast SE" was a new technique offering a distinct T1WI (TR/TE = 100/14, utilizing a 14 second breath hold). Slice thickness of "fast SE" was 10 mm and slice plane was selected perpendicular to the tumor base to detect the extent of invasion. Serial scan of "fast SE" was performed before and immediately after 0.1 mmol/kg Gd administration. Scanning was completed before the bladder was opacified by Gd. Tumor and normal mucosa were both markedly enhanced whereas the surrounding muscle layer remained hypointense. On delayed scan, the elevated character of the tumor was outlined by opacified urine but the distinction between the mucosa and the muscle layer became unclear. Total cystectomy (TC) was performed in 6 of 18 cases and pathological tumor extension was correlated with MR findings. Transurethral resection (TUR) was performed in the remaining 12 patients, and the tumor extension was assessed by follow-up biopsy after TUR. Intact liner hypointensity indicated superficial lesions (= less than pT2), while disruption of the linear hypointensity corresponded pathologically to deep muscle invasion (= greater than pT3a). Accuracy of serial "fast SE" in tumor staging was 94% (17/18). Serial "fast SE" allowed the distinction of superficial from invasive tumors more accurately than conventional studies, and therefore assisted in choosing the correct operative method.

Adult↗