Machine learning-based model for prediction and feature analysis of recurrence in pancreatic neuroendocrine tumors G1/G2

BACKGROUND

Pancreatic neuroendocrine neoplasms (PanNENs) are a heterogeneous group of tumors. Although the prognosis of resected PanNENs is generally considered to be good, a relatively high recurrence rate has been reported. Given the scarcity of large-scale reports about PanNEN recurrence due to their rarity, we aimed to identify the predictors for recurrence in patients with resected PanNENs to improve prognosis.

METHODS

We established a multicenter database of 573 patients with PanNENs, who underwent resection between January 1987 and July 2020 at 22 Japanese centers, mainly in the Kyushu region. We evaluated the clinical characteristics of 371 patients with localized non-functioning pancreatic neuroendocrine tumors (G1/G2). We also constructed a machine learning-based prediction model to analyze the important features to determine recurrence.

RESULTS

Fifty-two patients experienced recurrence (14.0%) during the follow-up period, with the median time of recurrence being 33.7 months. The random survival forest (RSF) model showed better predictive performance than the Cox proportional hazards regression model in terms of the Harrell's C-index (0.841 vs. 0.820). The Ki-67 index, residual tumor, WHO grade, tumor size, and lymph node metastasis were the top five predictors in the RSF model; tumor size above 20 mm was the watershed with increased recurrence probability, whereas the 5-year disease-free survival rate decreased linearly as the Ki-67 index increased.

CONCLUSIONS

Our study revealed the characteristics of resected PanNENs in real-world clinical practice. Machine learning techniques can be powerful analytical tools that provide new insights into the relationship between the Ki-67 index or tumor size and recurrence.

Performance of novel tissue harmonic echo imaging using endoscopic ultrasound for pancreatic diseases

BACKGROUND AND STUDY AIMS

Recently, tissue harmonic echo (THE) imaging has advanced with the development of a new endoscopic ultrasound (EUS) monitor/processing unit. With this new technology, penetration (THE-P) and resolution (THE-R) images can be obtained. The aim of this study was to investigate the performance of this novel THE imaging using a new processing unit for pancreatic diseases.

PATIENTS AND METHODS

Fifty patients with pancreatic lesions (38 cystic, 12 solid) were retrospectively analyzed. At each examination, 3 EUS images of the same pancreatic lesion were obtained using B-mode, THE-P mode, and THE-R mode imaging. Each set of EUS images was randomly arranged and evaluated independently by 4 physicians blinded to the imaging technique. Images were compared using a Likert scale 5-point grading system for each parameter.

RESULTS

For cystic lesions, THE-P mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, nodules, and total image quality (P < 0.05). THE-R mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, and total image quality (P < 0.05). However, for solid lesions, there was no significant difference in all the evaluation points between THE-P and conventional B-mode images. THE-R mode images were inferior to conventional B-mode images for visualizing the boundary, internal structure, and total image quality (P < 0.05).

CONCLUSIONS

For pancreatic cystic lesions, THE mode images provided better lesion characterization than conventional B-mode images. Further research is required to determine if this improvement will result in improved EUS diagnostics.

Feasibility, efficacy, and predictive factors for the technical success of endoscopic nasogallbladder drainage: a prospective study

BACKGROUND/AIMS

Several studies have shown the useful-ness of endoscopic nasogallbladder drainage (ENGBD) in patients with acute cholecystitis. However, the procedure is difficult, and factors that affect technical success have not yet been clarified. We conducted a prospective study to eval-uate the technical feasibility, efficacy, and predictive factors for the technical success of ENGBD in patients with acute cholecystitis.

METHODS

All patients with moderate or severe acute cholecystitis who were enrolled underwent ENGBD between April 2009 and April 2011. Patients with surgically altered anatomy or pancreatobiliary malignancies were ex-cluded. The primary outcomes included technical success, clinical success, and complications. Factors that could affect the technical success were also examined.

RESULTS

Of the 27 patients who underwent ENGBD during the study period, technical success was achieved in 21 (78%) and clinical improvement was achieved in 20 (95%). Early complications were encountered in four patients (15%). Gallbladder wall thickness (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.08 to 2.47) and age (OR, 1.16; 95% CI, 1.00 to 1.35) were effective predictors of technical failure.

CONCLUSIONS

ENGBD was effective in resolving acute cholecystitis; however, this modality was technically challenging and had a limited suc-cess rate. Because of technical difficulties, ENGBD should be reserved for limited indications. (Gut Liver, 2015;9239-246).

Diagnostic ability of EUS-FNA for pancreatic solid lesions with conventional 22-gauge needle using the slow pull technique: a prospective study

OBJECTIVE

Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) using the slow pull technique (SP-FNA) has recently attracted attention as an effective tissue acquisition technique. However, efficacy of SP-FNA with a 22-gauge conventional needle remains unclear. The aim of this study is to evaluate the diagnostic ability of SP-FNA with a 22-gauge needle.

MATERIAL AND METHODS

Patients with a pancreatic solid lesion were prospectively enrolled in this study. SP-FNA was performed at two needle passes with a 22-gauge needle. One dedicated pathologist evaluated the obtained samples in terms of quantity (Grade 0: scant; Grade 1: inadequate; Grade 2: adequate), quality (Grade 0: poor; Grade 1: moderate; Grade 2: good), and blood contamination (Grade 0: significant; Grade 1: moderate; Grade 2: low), and provided a pathological diagnosis. Additional EUS-FNA was performed by applying suction (SA-FNA). The evaluation points were as follows: diagnostic accuracy of SP-FNA compared with that of SA-FNA, and the quantity, quality, and blood contamination level of SP-FNA-obtained samples.

RESULTS

We enrolled 40 cases. The diagnostic accuracy of SP-FNA was 90% (36/40). There was no significant difference in the accuracy between SP-FNA and SA-FNA (90% vs. 90%, p = 1.000). The samples obtained using SP-FNA were assessed as Grade 2 for quantity in 29 cases (73%), quality in 31 (78%), and blood contamination in 25 (63%).

CONCLUSIONS

Adequate, high-quality, and unsubstantially blood-contaminated samples could be obtained using SP-FNA. The diagnostic ability of SP-FNA was 90%, which appeared to be similar to that of SA-FNA.

[A case of 5-fluorouracil-induced hyperammmonia after chemotherapy for metastatic colon cancer]

A 79-year-old woman with colon cancer and multiple liver metastases was admitted to our hospital for systemic chemotherapy. She underwent first cycle of modified FOLFOX6 chemotherapy. She was confused on treatment day 5. Blood test revealed her serum ammonia level to be 121 microg/dl. We diagnosed 5-fluorouracil (5FU)-induced hyperammonemia. Conservative treatment resulted in improvement of metal status. The reason for hyperammonemia after administration of 5FU was the excess production of ammonium from metabolites of 5FU.

Whipple's disease: the first Japanese case diagnosed by electron microscopy and polymerase chain reaction

A 52-year-old man presented with diarrhea and 20 kg weight loss in one year. Enteroscopy showed diffuse yellow-white shaggy mucosa in the duodenum and jejunum. Biopsies of the duodenal mucosa revealed massive infiltration within the lamina propria by foamy macrophages strongly positive for periodic acid-Schiff stain. Electron microscopy demonstrated numerous bacilli within macrophages of the lamina propria. Tropheryma whipplei DNA was detected by polymerase chain reaction. The definitive diagnosis of Whipple's disease was made. Antibiotic therapy dramatically improved his clinical picture. This is the first Japanese case with Whipple's disease diagnosed by electron microscopy and polymerase chain reaction.

[Evaluation of time dependency of the acetazolamide effect on cerebral hemodynamics as measured by 99mTc-ECD single-photon emission computed tomography]

PURPOSE

Kuwabara et al. have examined the cerebral artery dilation with acetazolamide (ACZ) challenge test using PET. And, they reported that ACZ reaction came out time dependently. We have developed a unique SPECT's method using Technetium-99m ethyl cysteinate dimer (99mTc-ECD) to verify the results obtained by Kuwabara et al.

METHOD

1000 MBq of 99mTc-ECD was exactly divided into three syringes. Each of which was intravenous infused (i.v.) at rest, 7.5, and 20 minutes after ACZ administration. Data collection was started using dynamic SPECT immediately after 99mTc-ECD i.v. at rest. Using necessary data only, SPECT images representing each of the three 99mTc-ECD i.v. was reconstructed. SPECT counts were obtained by the ROI method from each images to calculate relative CBF from rest to 7.5 and 20 minutes after ACZ administration.

RESULT

The 18 hemispheres of nine patients in the negative control group in whom ACZ was not loaded. CBF was stable during the three evaluation. The measurement error our method was estimated as small. The 18 hemispheres of nine patients in the positive control group who has normal vasodilatory reserve, CBF was increased by 26.2 +/- 8.1% at 7.5 minutes and 29.3 +/- 13.1% at 20 minutes after ACZ administration. Seven patients with and chronic stage unilateral internal carotid artery severe stenosis and/or occlusion were evaluated as the test group. Case of unaffected side, CBF was increased by 17.6 +/- 6.9% at 7.5 minutes and 24.8 +/- 11.3% 20 minutes after ACZ administration. And, increase rate of CBF in the affected side was 2.8 +/- 1.6% at 7.5 minutes and 17.3 +/- 5.0% at 20 minutes after ACZ administration. In the affected side, timing of the maximum CBF increase caused by ACZ was remarkably delayed.

CONCLUSION

Our method based on 99mTc-ECD SPECT also revealed delayed cerebral artery dilation in the affected side. It was suggested that ACZ reaction came out time dependently, as reported by Kuwabara et al.

A three-dimensional model of the human pulmonary acinus

A three-dimensional (3-D) model of the human pulmonary acinus, a gas exchange unit, is constructed with a labyrinthine algorithm generating branching ducts that fill a given space completely. Branching down to the third respiratory bronchioles is generated with the proposed algorithm. A subacinus, a region supplied by the last respiratory bronchiole, is approximated to be a set of cubic cells with a side dimension of 0.5 mm. The labyrinthine algorithm is used to determine a pathway through all cells only once, except at branching points with the smallest path lengths. In choosing each step of a pathway, random variables are used. Resulting labyrinths have equal mean path lengths and equal surface areas of inner walls. An alveolus can be generated by attaching alveolar septa, 0.25 mm long and 0.1 mm wide, to the inner walls. Total alveolar surface area and numbers of alveolar ducts, alveolar sacs, and alveoli in our 3-D acinar model are in good accordance with those reported in the literature.

A three-dimensional model of the human airway tree

A three-dimensional (3D) model of the human airway tree is proposed using a deterministic algorithm that can generate a branching duct system in an organ. The algorithm is based on two principles: 1) the amount of fluid delivery through a branch is proportional to the volume of the region it supplies; and 2) the terminal branches are arranged homogeneously within the organ. These principles define the basic process of branching: generation of the dimensions and directionality of two daughter branches is governed by the properties of the parent branch and the region the parent supplies. The algorithm is composed of nine basic rules and four complementary rules. When the contour of an organ and the position of the trunk are specified, branches are successively generated by the algorithm. Applied to the human lung, the algorithm generates an airway tree that consists of approximately 54,000 branches. Its morphometric characteristics are in good agreement with those reported in the literature. The algorithm and the 3D airway model are useful for studying the structure-function relationship in the lung.

[Simulations of bronchial displacement owing to solitary pulmonary nodules]

On the basis of elasticity dynamics, we constructed mathematical models of bronchial displacements caused by well-differentiated adenocarcinoma and inflammatory pulmonary nodules. We simulated bronchial displacement with a three-dimensional model of the airway tree that we constructed. One-hundred sixty simulations of cancerous and inflammatory displacements were performed, where 20 nodule centers were placed in the right upper lobe in the three-dimensional bronchial model and four different sizes (30 mm, 37.5 mm, 45 mm, and 60 mm) of original lesions were assumed which contracted to nodules of 15 mm in diameter. The three-dimensional simulation images were highly similar to the cancerous or inflammatory nodules in the clinical images. Angles and distances in simulated structures between respective branches and the nodule center were measured. The mean value of angles of branches whose distance from the nodule center was within a range of 6 mm to 12 mm was in good accordance with the value obtained theoretically. Discrimination between cancer and inflammation was successfully carried out by examining the distance dependency of the angles. We concluded that the measurement of angles of linear structures surrounding a pulmonary nodule would be useful for its differential diagnosis.

Primary adenocarcinoma in the urethrorectal fistula

A 60-year-old Japanese man was hospitalized because of urinary leakage from the anus on October 3, 1994. Retrograde urethrography detected a fistula between the bulbous urethra and the rectum. Urethrocystoscopy revealed a tumor on the urethrorectal fistula. Tumor biopsy showed a well differentiated adenocarcinoma. Cystourethrectomy with fistulectomy, and ileal conduit urinary diversion were performed. Pathological examination revealed primary adenocarcinoma in the fistula with invasion to the prostatic urethra and bladder wall. The patient showed no evidence of a recurrence as of August, 1996.

Malignant mesenchymoma arising from the prostate in Gardner's syndrome

The first case of a primary malignant mesenchymoma arising from the prostate in Gardner's syndrome is reported. The neoplasm occurred in a 40-year-old man with a chief complaint of urinary retention. Biopsy findings were primary malignant mesenchymoma. Total cystectomy and lymphadenectomy were performed, but the patient died due to multiple metastases within 6 months. He had undergone a colectomy for polyposis coli 17 years earlier and had mandibular osteomas. This was the first case of malignant mesenchymoma arising from the prostate in Gardner's syndrome.

The endocrine pancreas of spontaneously diabetic db/db mice: microangiopathy as revealed by transmission electron microscopy

Abnormalities in ultrastructures of islet capillaries were detected in db/db mice, with the visual inspection and morphometry of electron micrographs. The observed changes are: (1) capillary scarcity; (2) increase in the mean and diversity of capillary size; (3) pericapillary edema and fibrosis; (4) hypertrophy of the pericyte and abundance therein of actin-like microfilaments; and (5) luminal irregularity. Changes (2), (3) and (4) are conceived to indicate hyperperfusion, capillary hypertension and secondary vascular response. In particular, such pericyte changes were found to be shared by other organs whose capillaries are susceptible to diabetic complications.

Reinnervation of allografted pancreatic islets in the rat liver

Rat pancreatic islets were allografted in the liver and were studied morphologically in order to evaluate possible reinnervation. Islets isolated from rat pancreas were allotransplanted in the liver of streptozocin-induced diabetic rats via the portal vein. Electron microscopy revealed nerve endings with synaptic vesicles in the transplanted islets 100 days after transplantation, whereas axons in the islets appeared to degenerate several hours after isolation and prior to transplantation. These findings suggest that the nerve endings observed in the transplanted islets regenerate from nerves that innervate the recipient's liver. The tissue specimens were also investigated immunohistochemically using antityrosine hydroxylase antibody, and histochemically by the modified Karnovsky and Roots' method for visualizing acetylcholinesterase. Some nerve endings in the transplanted islets reacted positively to antityrosine hydroxylase antibody. Acetylcholinesterase was visualized in other nerves. These results indicate that norepinephrine- and acetylcholinesterase-containing nerves may reinnervate the transplanted islets.

Chemopreventive effects of tamoxifen in ethyl methanesulphonate-induced rat mammary carcinogenesis

Ethyl methanesulphonate (EMS), an alkylating agent and a potent mutagen, has been shown to be an effective carcinogen for the induction of mammary carcinoma in female Wistar King A rats. We therefore utilized this new system to assess the effects of tamoxifen (TAM) on mammary carcinogenesis. In Group A rats, given EMS orally for a period of 12 weeks, mammary carcinomas were first detected at the 13th week and were found in all surviving rats at the 20th week. The concomitant administration of TAM for 4 weeks, in Group B rats, retarded the development of the tumors significantly. There was a significant reduction in the incidence of estrogen receptor (ER)-positive tumors in the rats previously exposed to TAM; 100% in Group A versus 50% in Group B. Neither the progesterone receptor (PgR) nor androgen receptor (AR) status of the tumors were significantly different between these two groups. The inhibitory effects of TAM on tumor induction was also observed when TAM treatment started after EMS administration, though the intensity was smaller than that in Group B. These findings suggest the preventive action of TAM on EMS-induced mammary carcinogenesis, and indicate that this tumor system may provide a feasible model for research on chemoprevention and hormone therapy using an antiestrogen for human mammary carcinoma.

Hemodynamic effects of milrinone in patients with congestive heart failure--short- and long-term follow up studies

The hemodynamic effects of milrinone (Mil) were studied in 11 patients with congestive heart failure (CHF) and New York Heart Association (NYHA) functional class II-IV before and after a 2-week treatment. The plasma concentration of Mil was also determined and its pharmacokinetics analyzed. The effect of a placebo was examined before the initiation of the treatment. At the onset, the hemodynamic effects of a single oral dose of Mil (7.5 mg) were evaluated. Mil increased the cardiac index significantly (p < 0.05) 4 h after administrations from 2.3 +/- 0.4 to 2.9 +/- 0.6 L/min/m2. The pulmonary capillary wedge pressure (PCW) was lowered significantly by Mil (p < 0.05) between 0.5 and 4 h after administration. After a 2-week treatment, the baseline PCW dropped (p < 0.05) and the NYHA functional class improved in 10 patients. One patient remained in the same class (II). The improved NYHA class was maintained in 6 patients tested after a mean interval of 16 +/- 3 months. Single oral administration of Mil (7.5 mg) induced hemodynamic improvements after 2-week treatment and the drug also induced similar improvements even after the chronic oral therapy with Mil for 16 +/- 3 months. Pharmacokinetic analysis showed a significant increase in the area under the curve after 2 weeks of treatment. We conclude that Mil decreases the PCW and probably increases the cardiac index and thus improves the symptoms and NYHA functional class in patients with CHF.

Pure progressive autonomic failure presenting severe orthostatic hypotension

A 59-year-old woman showed chronic progressive autonomic failure consisting of orthostatic hypotension and dyshidrosis. No signs of Parkinsonism, cerebellar or peripheral neuropathy were observed. Autonomic nervous function tests and findings of biopsied sural nerve suggested that this case had both sympathetic and parasympathetic dysfunctions, mainly postganglionic. A decrease in the total peripheral resistance and no increase in the heart rate on standing seemed to be the mechanism of orthostatic hypotension in this case. We conclude that pure PAF can be recognized as a distinct clinical syndrome of systematic degeneration of the autonomic nervous system.

Suppression of ventricular premature contractions continues after the washout of antiarrhythmic drugs

The effects of the washout of antiarrhythmic drugs on the frequency of ventricular premature contraction (VPC) were investigated in 64 patients (VPCs > 2000/day). Included were patients on mexiletine (300-600 mg/day; 23 patients), disopyramide (300-600 mg/day; 19 patients) and atenolol (50 mg/day; 22 patients). Holter monitoring was repeated before, during and after the treatment with the above 3 drugs and the efficacies of the drugs were evaluated based on the spontaneous variability before the treatment. VPC reduction exceeding the calculated spontaneous variability during drugs therapy (drug-responders) and after the washout of the drugs (wash-responders) was noted in 17 (63%) and 3 (13%) of the mexiletine group; 11 (58%) and 5 (26%) of the disopyramide group; and 13 (59%) and 8 (36%) of the atenolol group, respectively. For the entire group of 64 patients, wash-responders were noted significantly (p < 0.05) more among drug-responders (14 of 41 patients; 34%) than drug-nonresponders (2 of 23 patients; 9%). Therefore, the antiarrhythmic effects of drugs observed during drugs therapy seem to continue even after the discontinuation of antiarrhythmic drugs in 34% of patients those whose VPC reduction exceeded the spontaneous variability (drug-responders).

Similarity of the constituents between glomerular arteriolar and mesangial lesions in experimental diabetes

In our previous studies in experimental diabetic rats, we have observed close similarities of ultrastructure and accumulation of IgG and IgM between the mesangial expansion and arteriolar hyalinosis of the glomerulus, and have presumed that both diabetic lesions are essentially of similar nature. In the present study, we carried out a further study on the constituents of both these lesions, using the PA-TCH-SP-PD technique for neutral carbohydrates, sialic acid and glycoproteins and the IgG-gold-silver technique for type IV collagen and fibronectin. The above staining and immunolabelings proved to be comparable in both lesions of diabetic glomerulopathies. This argues for the hypothesis of the identity of the two lesions.

Periodicity of insulin secretion comprises multiple cycles with different duration in perfused rat islets

Insulin secretion from pancreatic islets has been found to be periodic by in vivo and in vitro experiments. The pacemaker which regulates the periodicity may be localized in the central nervous system or in the pancreas, though the precise location and the mechanisms of generating pacing have not been determined. In order to solve these problems, we examined the period of secretory cycles of insulin in isolated islets using a prolonged perfusion system, and investigated the effects of glucose and other agents on these periods. Isolated islets from male Wistar rats were enclosed in a millipore holder and were perfused with MEM containing 1 mg/ml glucose at a flow rate of 0.3 ml/min for 240 min. The effluent was collected at 1-min intervals to measure insulin secretion. The results were analyzed by the maximum entropy method to demonstrate the periodicity of insulin secretion. When islets were perfused with 1 mg/ml glucose, the periodicity comprised five cycles with different duration: 71.5 +/- 14.6 min, 29.8 +/- 3.4 min, 19.2 +/- 1.5 min, 11.6 +/- 2.1 min and 4.3 +/- 0.4 min. This indicates the presence of a pacemaker within the islets, although, in vivo, participation of a higher center to control periodicity has to be taken into account. Further, the presence of a long cycle (71.5 +/- 14.6 min) of insulin secretion which previously has only been observed in vivo was first demonstrated in this in vitro study. The cycles were consistent even in islets which were desensitized to glucose by cultivating in a high glucose medium for 5 days before perfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

QT interval shortening and ST elevation in intracoronary ECG during PTCA

Percutaneous transluminal coronary angioplasty (PTCA) can provide a unique model of transient and reversible myocardial ischemia. The aim of this study was to assess the serial changes in QT interval during elective PTCA-induced transient ischemia. The serial changes in QT interval before, during, and after PTCA of the left anterior descending artery (LAD) were measured in patients who showed ST elevation in intracoronary electrocardiogram. Twelve consecutive patients who showed ST-segment elevation during PTCA-induced ischemia anterior precordial leads of the electrocardiogram (ECG) were enrolled in the present study. Target lesions for PTCA were all in the LAD. There were six patients with angina pectoris, two with non-Q-wave infarction, and four with Q-wave myocardial infarction. During balloon inflation, QTc interval shortened in both intracoronary ECG (ic-ECG) (0.472 +/- 0.013 vs 0.436 +/- 0.014) and surface ECG (0.462 +/- 0.012 vs 0.438 +/- 0.011). However, a significant shortening of the QT interval was more rapidly observed in the ic-ECG (20 s) than in the surface ECG (40 s). We conclude that the QT interval in both ic-ECG and surface ECG becomes shortened in PTCA-induced myocardial ischemia, and that the ic-ECG might be a good probe for detecting survived viable myocardium in the infarcted zone.

Ultrastructural and immunohistochemical similarities between glomerular arteriolar and mesangial lesions in experimental diabetes

It has thus far been speculated that plasma proteins have leaked and accumulated in diabetic expanded mesangium. We have previously shown that glomerular arteriolar hyalinosis has frequently occurred and has consisted of basement membrane-like extracellular matrix in alloxan diabetic rats. In the present study, the two diabetic glomerular lesions, arteriolar hyaline nodules and increased mesangial matrix, were comparatively evaluated by means of electron microscopy and immunohistochemistry. It was revealed that both of these lesions contained, in common, finely particulate extracellular matrix mingled with cytoplasmic fragments, and exhibited intense immunoreactions for IgG and IgM. It is indicated that both types of diabetic glomerular lesions are essentially of the same nature.

Allergic granulomatosis and angiitis with severe cardiac disease: a case in which cardiac function was extremely improved by long-term steroid therapy

A 38-year-old man with a history of bronchial asthma developed marked eosinophilia, mononeuritis multiplex and transient pulmonary infiltration. Pathological findings from the lung and nerve biopsy were helpful in determining the diagnosis as allergic granulomatosis and angiitis (AGA). Echocardiogram indicated dilation of the left ventricle with impaired systolic contraction. Coronary arteriography demonstrated significant stenosis only in the peripheral segment of the circumflex artery. After 1 year of corticosteroid therapy, echocardiogram revealed improvement of left ventricular contractility evaluated by ejection fraction (from 28% to 67%). To our knowledge, no previous reports have described amelioration of severe cardiac lesions during long-term steroid treatment in patients with AGA.

A case of primary biliary cirrhosis associated with Hashimoto's thyroiditis, scleroderma and Sjögren's syndrome

A 53-year-old woman was admitted because of Raynaud's phenomenon, polyarthralgia and polymyalgia. Biopsy specimens of the liver and thyroid gland revealed characteristic findings of primary biliary cirrhosis (PBC) (stage I by Scheuer's classification) and chronic thyroiditis. Her clinical features were also complicated by scleroderma (type I by Barnett's classification) and Sjögren's syndrome (Sjs) with keratoconjunctivitis sicca. Thyroid hormone replacement therapy led to improvement in thyroid function, normalization of the biliary tract enzymes and alleviation of subjective symptoms.

[The effects of isosorbide dinitrate spray on the coronary artery and its modification by the preceding chronic oral therapy with long acting isosorbide dinitrate]

The vasodilatory effect of a new formula of isosorbide dinitrite (ISDN) spray on the left coronary artery was studied by comparing its effects in 46 consecutive patients who subsequently received intracoronary injection with ISDN (2.5 mg). In addition, the influence long acting and ISDN for chronic cases on the vasodilatory effects of ISDN spray and on subsequent intracoronary injection of ISDN was investigated. The patients were divided into two groups, those who had had chronic oral ISDN (Group N; 29 patients) and those who had not (Group O; 17 patients). The vasodilatory effect of ISDN spray was evaluated in segments; 5, 6, 8, 11 and 12 by AHA classification and it dilated those segments by 9.9%, 13.2%, 21.5%, 15.6% and 23.5% respectively. Subsequent intracoronary injection of ISDN dilated those segments by 10.4%, 14.0%, 27.2%, 17.9% and 29.1% respectively. The differences in the degree of vasodilation caused by ISDN spray and that caused by injection in segments 8, 11, 12 were statistically significant. However, the per cent dilation of ISDN spray in segments 5 in group N was 5.9%, and 18.4% in group O, revealing a significant difference depending on previous chronic administration of long acting ISDN. We conclude that ISDN spray did dilate the coronary artery, and subsequent intracoronary administration of ISDN dilated it further in the distal portions of the left coronary artery. Long acting oral ISDN for chronic cases seemed to attenuate the vasodilatory action of ISDN.

Evidence for secretion of 7B2 by A- and B-cells of hamster pancreatic islets

7B2 is a neuroendocrine protein, and in the pancreatic islets the presence of 7B2 in A- and B-cells was immunohistochemically demonstrated. In order to examine 7B2 secretion by A- and B-cells of pancreatic islets, we prepared isolated hamster pancreatic islet cells as well as an A-cell-rich culture, and studied 7B2 secretion under certain stimulations. 7B2 was secreted by isolated hamster pancreatic islet cells. This secretion was stimulated by theophylline and arginine, but glucose had a weak effect on the 7B2 secretion. Such a response of 7B2 to the stimulations was different from that of insulin or glucagon. 7B2 secretion was also noted in the A-cell-rich culture. These results suggest that 7B2 is secreted by both A- and B-cells of the hamster pancreatic islets and its secretion is regulated under certain conditions.

Autocrinological role of basic fibroblast growth factor on tube formation of vascular endothelial cells in vitro

When bovine capillary endothelial (BCE) cells plated on type I collagen gel were covered with a second layer of collage gel, BCE cells reorganized into a network of capillary-like structures. In the presence of affinity purified anti-basic fibroblast growth factor (bFGF) antibody, this reorganization was inhibited. By using a computerized image analyzer, the formation of network structures and the effect of anti-bFGF antibody was quantitated. The inhibitory effect of anti-FGF antibody was dose-dependent and maximal inhibition was observed at 2.0 micrograms/ml of antibody. Exogenously added bFGF potentiated network formation of BCE cells and coadministration of bFGF abrogated the inhibitory effect of anti-bFGF antibody. Platelet factor 4, which blocks the binding of bFGF to its receptor, inhibited network formation. These results indicate that bFGF produced by endothelial cells regulates angiogenesis as an autocrine factor.

Loss of sulfated carbohydrate from the glomerular podocyte as a cause of albuminuria in experimental diabetic rats: ultrastructural histochemical study

Decrease of anionic sites and heparan sulfate proteoglycan has been demonstrated in diabetic glomerular basement membrane (GBM) and causally related to albuminuria. The HID-TCH-SP-PD technique is a sensitive histochemical method for negatively charged sulfated carbohydrates. In this study, we examined the localization of HID-TCH-SP-PD reaction in the glomeruli of diabetic and control rats. In both rats, the reaction was found in association with the surface of podocytes and with GBM. In diabetic rats, the former-associated reaction was markedly reduced. By contrast, the latter-associated reaction did not show any differences between both animal groups. Urinary albumin excretion (UAE) increased significantly in alloxanized rats. It is suggested that a decrease of podocyte-associated sulfated carbohydrates, the primary observed change, gives rise to albuminuria in alloxan diabetic rats.

Inhibitory effects of prostaglandin F2 alpha on mammary carcinogenesis induced by ethyl methanesulphonate in rats

The effect of prostaglandin F2 alpha (PGF2 alpha) on mammary carcinogens was examined for a new system in female rats, using ethyl methanesulphonate (EMS). The rats were given EMS orally for a period of 12 weeks starting at age 4 weeks. Mammary carcinomas were first detected at the 16th week and were found in all surviving rats at the 32nd week. The concomitant administration of PGF2 alpha for 8 weeks made the development of tumor retarded; i.e., the carcinomas were first detected at the 30th week and final tumor incidence at the 44th week was 61.1%. The incidence of developing mammary carcinomas and multiplicity (number of mammary carcinomas per rat) were significantly lower in PGF2 alpha treated rats than in those given EMS alone. The inhibitory effect of PGF2 alpha on tumor development was apparent when PGF2 alpha was concomitantly given to the rats with EMS at age 4 weeks, while PGF2 alpha injections after oral administration of EMS at age 16 weeks did not significantly retard tumor development. Histologically, no significant difference in morphology was observed between PGF2 alpha-treated and PGF2 alpha-non-treated rats in either the cancerous or noncancerous mammary tissues. The finding demonstrates that PGF2 alpha inhibits the development of EMS-induced mammary carcinomas when given to younger rats, presumably by affecting the hormonal status rather than by direct action on the mammary glands.

The stimulatory effect of PDGF on vascular smooth muscle cell migration is mediated by the induction of endogenous basic FGF

The migration of arterial smooth muscle cells from the media to the intima is a crucial event for the development of the atherosclerotic lesion, and platelet derived growth factor (PDGF) is thought to play an important role in this process. Here we report that the spontaneous migration of bovine smooth muscle (BSM) cells is dependent on endogenously produced basic fibroblast growth factor (bFGF). PDGF stimulates the migration of BSM cells and its effect is abolished by affinity purified anti-bFGF antibody. PDGF induces bFGF mRNA in BSM cells. These results indicate that the effect of PDGF on the migration of BSM cells may be mediated by the induction of endogenous bFGF.

Platelet factor 4 blocks the binding of basic fibroblast growth factor to the receptor and inhibits the spontaneous migration of vascular endothelial cells

Platelet factor 4 (PF-4) blocked the binding of basic fibroblast growth factor (bFGF) to the plasma membrane receptor. Five micrograms/ml of PF-4 completely blocked the specific binding of bFGF to the receptor of NIH 3T3 cells. Endogenously produced bFGF regulates the spontaneous migration of bovine aortic endothelial (BAE) cells as an autocrine factor (Sato and Rifkin, 1988). PF-4 inhibited the spontaneous migration of BAE cells in a reversible and dose dependent manner. The inhibition reached maximum at 5 micrograms/ml of PF-4, where the binding of bFGF to the receptor was completely blocked.

Effects of glucose and insulin on cultured human microvascular endothelial cells

The prolonged effects of glucose and insulin on cultured human microvascular endothelial cells from omental tissue (HOMEC) were observed to identify the contribution of sustained hyperglycemia and/or hyperinsulinemia to the pathogenesis of diabetic microangiopathy. When the cells were cultured for 10 days in Medium 199 with 100 or 500 mg/dl glucose, the number of cells was reduced to 78% in the culture of 500 mg/dl glucose as opposed to that of 100 mg/dl glucose. The difference in the number of cells between these two groups became obvious between the 5th and the 7th culture days. The replacement of D-glucose with L-glucose did not show any reduction in the number of cells, indicating the impertinence of high osmolarity, induced by high glucose (305 mOsm/kg) to the number of cells. This reduction resulted from the cellular damage during the culture period rather than the retardation of growth, according to the experiments of [3H]thymidine uptake and the 51Cr release assay. Since the uptake of glucose, measured as the uptake of 3-O-methyl-alpha-D-glucose, was higher and the Na+/K+ pump activity decreased in high glucose condition, it is suggested that the excessive intracellular accumulation of glucose caused the damage of cells through the disturbance of ion exchange. Insulin augmented the reduction in the number of cells induced by high glucose when supplemented together for 10 days at concentrations of 10(-6)-10(-12)M. The uptake of glucose increased further to 154% by the addition of insulin to high glucose as compared to that of high glucose alone, however, the decreased Na+/K+ pump activity by high glucose was restored to the control level by insulin. The aggravating effect of insulin to the cellular damage induced by high glucose seems to be mediation via the mechanism other than the decreased Na+/K+ pump activity. In conclusion, HOMEC were gradually damaged by high glucose and by insulin, and hyperglycemia and hyperinsulinemia would be of pathogenetic importance for diabetic microangiopathy.

Estrogen receptor status and effects of endocrine ablative surgery in ethyl methanesulphonate-induced rat mammary carcinoma

An experimental model of rat mammary carcinoma induced by oral administration of ethyl methanesulphonate (EMS) was characterized with reference to estrogen receptors (ER) and hormone dependency. After the administration of EMS, the mammary carcinomas developed more rapidly in the 4-week old rats than in the 16-week old rats. The developed mammary carcinomas were related to the ER status. Tumor development was prevented by ablative oophorectomy prior to EMS administration, but only partially, by adrenalectomy. These inhibitory effects on tumor development were more obvious when ablative surgery was performed on younger rats at age 4 weeks. In rats subjected to oophorectomy at after EMS administration at age 16 weeks, tumor induction was retarded but not completely prevented. Thus, it appears that mammary tumors induced by EMS are dependent on ovarian hormones and that mammary glands of the younger female rats are more sensitive to carcinogenic actions of EMS.

Chronic diabetes mellitus prolongs action potential duration of rat ventricular muscles: circumstantial evidence for impaired Ca2+ channel

STUDY OBJECTIVE

The aim of the study was to investigate the effects of chronic diabetes mellitus on electromechanical properties of ventricular papillary muscles.

DESIGN

Conventional glass microelectrodes and tension recording techniques were used in isolated hearts of rats made diabetic for 30-40 weeks by single intravenous injections of streptozotocin.

SUBJECTS

Experimental animals were male Wistar rats of 200-250 g. Diabetic rats (n = 14) were given streptozotocin 65 mg.kg-1; controls (n = 15) were given vehicle only.

MEASUREMENTS AND MAIN RESULTS

(1) The maximum upstroke velocity of the action potential duration of diabetic muscles was decreased compared to control, with no difference in the resting potential. (2) At all stimulation frequencies (0.2, 1 and 5 Hz), and particularly the lower ones, the action potential duration of diabetic muscles was longer than control. (3) In diabetic muscles, frequency dependent shortening of the late phase of action potential duration (APD75, APD90) was more pronounced, and frequency dependent lengthening of the early phase (APD25, APD50) was less pronounced. (4) A blocker of transient outward current, 4-aminopyridine, lengthened the early phase of action potential durations by the same amount in diabetic and control muscles. (5) A Ca2+ channel blocker, CoCl2, dramatically shortened all levels of action potential duration, with much greater effect on diabetic muscles. (6) Ryanodine lengthened the early phase of action potential duration and shortened the late phase in both diabetic and control muscles. It enhanced the difference between the groups in the early phase. (7) Developed tension in the presence of ryanodine (ryanodine resistant tension component) was greater in diabetic muscles than in control.

CONCLUSIONS

The findings suggest that altered Ca2+ current, but not altered Na(+)-Ca2+ exchange current or altered transient outward current, significantly prolongs action potential duration in diabetic rat ventricular muscles.

Effects of calcium antagonists on beta-receptors of cultured cardiac myocytes isolated from neonatal rat ventricle

The effects of calcium antagonists (verapamil, diltiazem, and nicardipine) on beta-adrenergic receptors of cultured cardiac myocytes isolated from neonatal rat ventricle were studied with the hydrophilic ligand [3H]CGP-12177, which identifies cell surface-bound beta-receptors. The three calcium antagonists suppressed spontaneous beating of the myocytes, increased the number of beta-receptors, but did not alter the affinity (Kd). These effects were dose and time dependent. Verapamil (10(-6) M) increased the beta-receptor density by about 13% after 6 hours of incubation, and this increase in density reached a plateau of about 45% after 24 hours of incubation. beta-Receptor density increased by 15% with 5 x 10(-7) M and by 37% with 10(-6) M verapamil. The increased beta-receptors appeared to retain their normal function, as assessed by the increased spontaneous beating of the myocytes in response to applied isoproterenol. The increase in beta-receptors was abolished by colchicine but not by cycloheximide. When the calcium ion concentration of the medium was lowered to 0.1 mM, no significant change occurred in the density of beta-receptors compared with that in 1.8-mM Ca2+ medium. The results suggest that calcium antagonists increase beta-receptors by accelerating recycling by microtubules but not by decreasing the inward calcium current. Such effects of calcium antagonists may be clinically important and promise insight into the mechanism of the withdrawal phenomenon of calcium antagonists.

Enzyme immunoassay of somatostatin (SS)-like immunoreactive substance in bovine milk

A sensitive and specific enzyme immunoassay (EIA) for somatostatin (SS)-like immunoreactivity (SS-LI) was developed with the use of beta-D-galactosidase labeled antigen. The minimum amount of SS-like immunoreactive substance (SS-IS) detectable by this method was 1.0 fmol/well (25 pmol/l). The level of SS-IS in bovine foremilk was about 20 pmol/l, and the level was unchanged after delivery. On the other hand, the levels of gastrin releasing peptide (GRP)-IS and vasoactive intestinal polypeptide (VIP)-IS in bovine foremilk were very high, but fell during 1 week after delivery to about 10% of those in foremilk.