Central nervous system action of melatonin on gastric acid and pepsin secretion in pylorus-ligated rats

We recently demonstrated that centrally administered melatonin at low doses inhibits the induction of gastric lesions by water-immersion restraint stress. To investigate the mechanism of the potent anti-ulcer action of melatonin, the central nervous system (CNS) effects of melatonin on gastric acid and pepsin secretion were studied in conscious pylorus-ligated rats. Intracisternal (i.c.) melatonin (1-100 ng) dose-dependently decreased acid and pepsin output, while a higher i.p. dose (1 microg) had no inhibitory effect. The i.c. melatonin did not change serum gastrin concentrations. Serum melatonin concentrations at 1 and 4 h after i.c. administration of 10-100 ng melatonin did not differ from those in rats receiving i.c. vehicle. The present results suggest that melatonin administered centrally modulates the secretion of gastric acid and pepsin which may explain, at least in part, the protective, anti-stress role of melatonin in the gastric mucosa observed in our previous study.

Stenting for airway obstruction in the carinal region

BACKGROUND

Recent progress on airway stents has provided sufficient airway patency for patients with airway obstruction; however, when the stenosis exists in the carinal zone, establishing an excellent airway condition is still troublesome because of the anatomic structure.

METHODS

We treated 15 patients with severe tracheobronchial stenosis involving a carinal bifurcation region, using several types of stenting devices (long T-tube, T-Y tube, wire reinforced Y tracheostomal tube, Freitag Dynamic stent [Karl Storz, Tuttlingen, Germany], and covered metallic stent). All patients had advanced inoperable tumors (lung cancer, n = 6; esophageal cancer, n = 3; thyroid cancer, n = 3; mediastinal tumor, n = 3).

RESULTS

All but 2 patients had immediate relief of respiratory symptoms. One patient died of respiratory failure caused by pulmonary lymphatic spread 3 days after Dynamic stent insertion. In 1 patient with severe left main bronchial stenosis due to lung cancer, effective palliation was not achieved by insertion of a covered metallic stent because of its insufficient expansion against the stenosis. Mean survival after successful stenting was 4.3 months (range, 1 to 15 months). There were no complications directly attributable to the stents.

CONCLUSIONS

As evidenced by the clinical effectiveness, airway stenting for inoperable tumor is valuable in such patients. Choosing a stent that will fully cover the lesion and allow sufficient tolerance against compression is important to successful stenting. Benefits such as ease of phonation and stent maintenance should also be considered.

High levels of hepatocyte growth factor/scatter factor in diffuse-type bronchioloalveolar cell carcinoma

BACKGROUND

Hepatocyte growth factor/scatter factor (HGF/SF) is a potent mitogen for various neoplastic cells, including neoplastic bronchial epithelia.

METHODS

Immunoreactive hepatocyte growth factor/scatter factor (HGF/SF) was measured in extracts prepared from 129 nonsmall cell lung carcinoma (NSCLC) specimens, using an enzyme-linked immunosorbent assay. These specimens represented 5 cases of solitary/localized bronchioloalveolar cell carcinoma (BAC), 4 cases of diffuse/infiltrative BAC, 90 cases of non-BAC adenocarcinoma, 25 cases of squamous cell carcinoma, and 5 cases of large cell carcinoma.

RESULTS

The mean concentration of immunoreactive HGF/SF was more than 19-fold higher in tissue extracts from diffuse-type BAG (265.0 +/- 110.2 ng/100 mg protein) than in those from solitary-type BAC (13.9 +/- 15.9, P < 0.005), non-BAC adenocarcinoma (13.8 +/- 14.9, P < 0.001), squamous cell carcinoma (13.2 +/- 14.4, P < 0.001), or large cell carcinoma (11.2 +/- 6.5, P < 0.005). When immunohistochemical staining for HGF/SF was performed, intense HGF/SF staining was uniformly observed in diffuse-type BAC tumor cells, but not in solitary-type BAC.

CONCLUSIONS

Although BAC is included as a subtype of adenocarcinoma in the World Health Organization classification, diffuse-type BAC should be considered a distinct biologic entity, at least in terms of HGF/SF expression, from solitary-type BAC or non-BAC adenocarcinoma. In addition, the solitary and diffuse forms of BAC are known to be associated with different prognoses; for the latter, the prognosis is much poorer than for the former. The results of this study may at least partly explain this difference in prognosis.

A 10 MV x-ray zero-area tissue-maximum ratio expression constructed by taking into account depth and off-axis beam quality change

A 10 MV x-ray zero-area TMR (tissue-maximum ratio) expression was constructed using an attenuation coefficient expression which is a function of depth (z) and off-axis distance (r). The zero-area TMR expression can take into account depth and off-axis beam quality change. The construction is based on a method of convolving one-dimension forward and backward primary dose-spread functions with the primary water collision kerma. Additional information required to construct the zero-area TMR expression for a given fanline at an off-axis distance of r is the zero-area TMR value at z = 0 [Ds(r)] and the v(r) and w(r) values in the backward primary dose-spread function. It was found that the depth of peak zero-area TMR [zpeak(r)] decreases with increasing r and that for large depths, the zero-area TMR expression changes significantly as a function of r. Obtaining an accurate expression for zero-area TMR is important for accurate construction of the three-dimensional (3D) forward and backward primary dose-spread functions needed for a 3D convolution method.

Thoracoscopic transdiaphragmatic microwave coagulation therapy for a liver tumor

BACKGROUND

Microwave coagulation therapy (MCT) for hepatocellular carcinoma, which induces tumor coagulonecrosis, is now recognized as an efficient treatment. However, when a tumor is located just below the top of the diaphragmatic dome, laparotomical MCT requires a large incision, and percutaneous MCT is sometimes impossible.

PATIENTS AND METHODS

The patients were four men and two women. There were four cases of hepatocellular carcinoma and two cases of liver metastasis from colorectal cancer. All tumors were located below the top of the diaphragmatic dome. Thoracoscopic transdiaphragmatic MCT (TTMCT) was performed under general anesthesia using an endotracheal double-lumen tube. Identification of the tumor site in the liver was performed using an ultrasonic probe under thoracoscopic observation. After the diaphragm above the tumor was opened, a needle electrode to transmit microwaves was inserted directly into the tumor. Microwave irradiation was repeated to coagulate the entire lesion. After completion of TTMCT, the diaphragm was closed thoracoscopically.

RESULTS

TTMCT was successfully administered to cancerous lesions in all six patients. The postoperative course was uneventful, and the average postoperative hospitalization period was 10.5 days. None of the patients has shown any recurrence during a follow-up period of 4-23 months.

CONCLUSIONS

TTMCT was performed without any difficulty using the thoracoscopic surgical technique, and its therapeutic outcome was satisfactory. This is effective for tumors located just below the top of the diaphragmatic dome.

Predominant role for directly transfected dendritic cells in antigen presentation to CD8+ T cells after gene gun immunization

Cutaneous gene (DNA) bombardment results in substantial expression of the encoded antigen in the epidermal layer as well as detectable expression in dendritic cells (DC) in draining lymph nodes (LNs). Under these conditions, two possible modes of DC antigen presentation to naive CD8+ T cells might exist: (a) presentation directly by gene-transfected DC trafficking to local lymph nodes, and (b) cross-presentation by untransfected DC of antigen released from or associated with transfected epidermal cells. The relative contributions of these distinct modes of antigen presentation to priming for cytotoxic T cell (CTL) responses have not been clearly established. Here we show that LN cells directly expressing the DNA-encoded antigen are rare; 24 h after five abdominal skin bombardments, the number of these cells does not exceed 50-100 cells in an individual draining LN. However, over this same time period, the total number of CD11c+ DC increases more than twofold, by an average of 20,000-30,000 DC per major draining node. This augmentation is due to gold bombardment and is independent of the presence of plasmid DNA. Most antigen-bearing cells in the LNs draining the site of DNA delivery appear to be DC and can be depleted by antibodies to an intact surface protein encoded by cotransfected DNA. This finding of predominant antigen presentation by directly transfected cells is also consistent with data from studies on cotransfection with antigen and CD86-encoding DNA, showing that priming of anti-mutant influenza nucleoprotein CTLs with a single immunization is dependent upon coexpression of the DNAs encoding nucleoprotein and B7.2 in the same cells. These observations provide insight into the relative roles of direct gene expression and cross-presentation in CD8+ T cell priming using gene gun immunization, and indicate that augmentation of direct DC gene expression may enhance such priming.

The sodium channel has four domains surrounding a central pore

The voltage-gated sodium channel generates the action potential. This 300-kDa protein has four homologous regions, which are also homologous to the voltage-sensitive tetrameric potassium channel. We isolated sodium channels from Electrophorus electricus electroplax by detergent solubilization and immunoaffinity chromatography and studied their structure by electron microscopy of negatively stained specimens. Different projections were aligned, classified, and averaged. In side view, the channel protein exhibits the shape of a truncated cone, 14 nm in height. One end has a diameter of 12 nm and is asymmetric, while the other is more symmetric and has a diameter of 7-10 nm. In top views, the sodium channel appears to consist of four domains of different size and to have a stain-filled pore in the center.

Central nervous system action of melatonin on gastric acid and pepsin secretion in pylorus-ligated rats

We recently demonstrated that centrally administered melatonin at low doses inhibits the induction of gastric lesions by water-immersion restraint stress. To investigate the mechanism of the potent anti-ulcer action of melatonin, the central nervous system (CNS) effects of melatonin on gastric acid and pepsin secretion were studied in conscious pylorus-ligated rats. Intracisternal (i.c.) melatonin (1-100 ng) dose-dependently decreased acid and pepsin output, while a higher i.p. dose (1 microg) had no inhibitory effect. The i.c. melatonin did not change serum gastrin concentrations. Serum melatonin concentrations at 1 and 4 h after i.c. administration of 10-100 ng melatonin did not differ from those in rats receiving i.c. vehicle. The present results suggest that melatonin administered centrally modulates the secretion of gastric acid and pepsin which may explain, at least in part, the protective, anti-stress role of melatonin in the gastric mucosa observed in our previous study.

Inhaled nitric oxide does not increase rat pulmonary allograft rejection

BACKGROUND

There is evidence that inducible nitric oxide (NO) may be directly related to the process of allograft rejection. Because of its strong pulmonary vasodilatory activity, inhaled NO (INO) has recently been used as a therapeutic option for allograft dysfunction after lung transplantation. The action of inducible NO and inhaled NO seems contradictory for preserving posttransplantation pulmonary allograft function. INO used for lung transplant recipients may actually enhance acute allograft rejection. We studied the effect of INO on acute allograft rejection with a rat pulmonary allograft model.

METHOD

A total of 24 left lung allotransplantations were performed from Lewis donors into F344 recipients. Animals were divided into two groups and inhaled either room air alone or 20 ppm NO with room air in a closed chamber immediately after transplantation until rats were killed on days 7 and 14. During observation, NO uptake was monitored by measuring serum NO2-/NO3- level. Acute rejection was evaluated by use of a semiquantitative radiographic scoring method (aeration score: 0 to 6, opaque to normal appearance) and rejection score (0 to 4, no sign of rejection to diffuse mononuclear infiltration).

RESULTS

Markedly elevated serum NO2-/NO3- levels were observed in the NO inhalation group compared with levels in the normal air inhalation control group (110.8 +/- 25.3 vs 16.3 +/- 4.0 micromol/L/ml on day 7, p < 0.01; 107.0 +/- 30.9 vs 16.8 +/- 4.8 micromol/L/ml on day 14, p < 0.01). However, no positive effect of INO on acute rejection was found histologically or radiographically.

CONCLUSION

The effect of INO on acute rejection is likely so minimal as not to be clinically relevant.

Successful pregnancy with sperm retrieved from the bladder after the introduction of a low-electrolyte solution for retrograde ejaculation

OBJECTIVE

To determine the safety and efficacy of the introduction of a low-electrolyte solution into the bladder before masturbation for sperm recovery in patients with retrograde ejaculation.

DESIGN

Two case reports.

SETTING

Assisted reproduction practice at a university hospital.

PATIENT(S)

Two men with retrograde ejaculation.

INTERVENTION(S)

A 0.32-mol/L glucose solution or Ham's modified F-10 medium (GIBCO, Grand Island, NY) with 10% serum was introduced into the urinary bladder before masturbation. The retrieved sperm were used for IUI.

MAIN OUTCOME MEASURE(S)

The motility of retrieved sperm, achievement of pregnancy, and outcome of pregnancy.

RESULT(S)

In patient 1, the motility rate of sperm retrieved from the bladder after the introduction of Ham's modified F-10 medium was higher than that after the introduction of a glucose solution. The patient's wife did not become pregnant during 10 IUI cycles after treatment with Ham's modified F-10 medium. However, she became pregnant during the first IUI cycle after treatment with a glucose solution and was delivered of healthy twin infants. The wife of patient 2 also became pregnant during the first IUI cycle after treatment with a glucose solution and was delivered of a healthy female infant.

CONCLUSION(S)

The introduction of a glucose solution appears to be a safe and simple method for sperm recovery in patients with retrograde ejaculation.

Extended operation for T4 lung carcinoma

The extended surgery for T4 lung carcinoma was reviewed. From literature in the last decade, the 5-year survival rate has been under 10% worldwide. However a more favorable prognosis will be expected nowadays because of the progress of perioperative intensive care and appearance of effective anticancerous agents for induction chemotherapy. We compared the results of surgery for T4 lung carcinoma from 1978 to 1989, to those from 1992 to 1997. The 3 and 5-year survivals in the former period were 6.8% respectively, however in the latter period the 3-year survival rate rose to 24.6%. In patients with T4, the prognoses are different according to the involved organs by lung carcinoma. Generally, combined resection of the trachea, carina, descending aorta and left atrium show better prognoses compared to that of the esophagus and liver. We consider that malignant pleural effusion with N2 should not be the object for panpleuropneumonectomy. In our series from 1992 to 1997 median survival time (MST) of T4 with N0 or N1 was 25.5 months, on the other hand MST with N2 or N3 was 14.2 months. Histologically patients with squamous cell carcinoma showed a better prognosis than those with adenocarcinoma. From these results, in the extended operation for T4 we may expect more favorable prognoses in cases with involvements of the trachea, carina, aorta and left atrium, and with N0 or N1, histologically squamous cell carcinoma.

Cyclic stretch upregulates production of interleukin-8 and monocyte chemotactic and activating factor/monocyte chemoattractant protein-1 in human endothelial cells

In vivo, vascular walls are exposed to mechanical stretch, which may promote atherogenesis. This study was designed to investigate the effect of mechanical stretch on the production and gene expression of cytokines in endothelial cells (ECs) of human umbilical veins. ECs were cultured on flexible silicone membranes and exposed to cyclic mechanical stretch. Although the secretion levels of interleukin (IL)-1beta, tumor necrosis factor-alpha, IL-6, granulocyte (G) -colony stimulating factor (CSF), G and macrophage (M) -CSF, and M-CSF were not affected by cyclic stretch over 24 hours, the levels of IL-8 and monocyte chemotactic and activating factor (MCAF)/monocyte chemoattractant protein-1 (MCP-1) were significantly increased by cyclic stretch. Northern blot analysis indicated that the mRNA levels of IL-8 and MCAF/MCP-1 were upregulated by cyclic stretch as a function of its intensity. Cytochalasin D, which disrupts the actin cytoskeleton, abolished the stretch-induced gene expression of IL-8 and MCAF/MCP-1. In contrast, neither inhibition of stretch-activated ion channels nor disruption of microtubules affected the induction of these chemokines by cyclic stretch. Northern blot analysis using enzyme inhibitors showed that phospholipase C, protein kinase C, and tyrosine kinase were involved in the stretch-induced gene expression of IL-8 and MCAF/MCP-1, whereas cAMP- or cGMP-dependent protein kinase was not. In conclusion, cyclic stretch enhanced the secretion and gene expression of IL-8 and MCAF/MCP-1 in a stretch-dependent fashion, and the integrity of the actin cytoskeleton and activities of phospholipase C, protein kinase C, and tyrosine kinase may be essential in the process of stretch-induced gene induction of IL-8 and MCAF/MCP-1.

Y-shaped tracheobronchial stent for carinal and distal tracheal stenosis

A Y-shaped tracheo-bronchial tube was designed and used for two patients with carinal stenosis following a lower tracheal resection in one case and a malignant tracheal fistula in the other. The tube consisted of three parts including a Y-shaped, thin-walled, soft silicone stent; a spiral-wire-reinforced main tube; and a curved tracheostomy tube. The stent was inserted easily and comfortably through the tracheostomy under fiberoptic bronchoscopic guidance with minimal local anesthesia. The positioning stability of the tube was excellent because of the carina-shaped structure of the tube end. Resistance to compression was satisfactory due to the embedded spiral wire. The insertion procedure through the tracheostomy was smooth, even in patients whose respiratory condition was severe or critical. Satisfactory phonational activity was also provided by breathing through the hole on the tube back up to the vocal cord. Bronchoscopic inspection was uncomplicated, and the patients themselves could easily clean the stent. Since palliation of the airway obstruction is the main purpose of such a stent for patients with either severe lower tracheal or carinal stenosis, and because of the difficulty of ordinary stent insertion in this part of the airway, this device appears to offer excellent stability and easy insertion of the stent. In addition, the ease of maintenance and suctioning through the tracheostomal end allows for an excellent quality of life in which the patients are able to return to their homes.

[Subcapsular hematoma of the liver after extracorporeal shock wave lithotripsy]

We experienced a case of a hepatic subcapsular hematoma after extracorporeal shock wave lithotripsy (ESWL) for a right renal stone. To our knowledge this presentation is the second case in the Japanese literature. A 63-year-old female with a right renal stone received 2,800 shots of 14.0 kilo-volts shockwave with Sonolith 3,000. Preoperative examination of the blood disclosed no abnormalities in the coagulating system except slight reduction of platelet count and slight impairment of liver function. Postoperative routine ultrasound echograms revealed a hepatic subcapsular hematoma although she had no symptom. The size of the hematoma measured 11.0 x 5.0 cm in computed tomograms (CT). She was carefully observed without any treatments because the hematoma did not increase in size. CT scans 6 months after the ESWL treatment demonstrated neither hematoma nor masses in the liver. As a complication of ESWL for urolithiasis a hepatic subcapsular hematoma is very rare. We herein presented the case and discussed the complications of ESWL briefly in the literature.

Transarterial embolization and ablation of renal arteriovenous malformations: efficacy and damages in 30 patients with long-term followup

PURPOSE

We evaluate the long-term efficacy and side effects of transarterial embolization and ablation for renal arteriovenous malformations.

MATERIALS AND METHODS

A total of 30 patients with cirsoid arteriovenous malformations causing massive hematuria underwent 34 procedures of embolization or ablation. We confirmed the ratios of occluded arteriovenous malformation areas on angiograms and those of infarcted areas on computerized tomography. All patients were followed for 4.1 to 15.0 years (mean 8.0 +/- 2.8) after the initial procedures.

RESULTS

Hematuria ceased in all patients after the initial procedures, including partial embolization or ablation of the arteriovenous malformations in 8. Massive hematuria recurred in 4 patients, who had undergone absorbable gelatin sponge (2), embolization, combined alcohol and subselective absorbable gelatin sponge embolization (1) and polyvinyl alcohol particles embolization (1). In these 4 cases total ablation of the arteriovenous malformations with alcohol was successful. In 29 patients, including aforementioned 4, no hematuria recurred after 5 years following total or partial ablation with alcohol. Large nontarget embolization with reflux of subselectively infused absorbable gelatin sponge caused a nonfunctioning kidney in 1 patient. The remaining 33 procedures caused 6.3 to 48.0% (mean 15.7 +/- 6.9%) areas of renal infarction. Polyvinyl alcohol embolization caused pulmonary embolism and renin dependent hypertension.

CONCLUSIONS

Partial or total transarterial ablation of arteriovenous malformations with alcohol proved effective for long-term cessation of hematuria. However, this procedure as well as transarterial embolization has the potential risk of nontarget infarction.

Helicobacter pylori, neutrophils, interleukins, and gastric epithelial proliferation

Infection of Helicobacter pylori causes chronic gastritis and plays an important role in the pathogenesis of gastroduodenal ulceration. H. pylori has also been suggested to be involved in the genesis of adenocarcincoma and MALT lymphoma of the stomach. H. pylori infection is associated with increased gastric epithelial proliferation, which can be reversed by a successful eradication of the organism. Although the mechanisms of increased gastric epithelial proliferation is not known, the enhanced epithelial proliferation is important in developing gastric carcinoma. Whether or not H. pylori de nove stimulates gastric epithelial proliferation is controversial, but gastric infection with H. pylori activates a mucosal inflammatory response by consisting of large numbers of polymorphonuclear and mononuclear cells, that also includes expression of various cytokines including interleukin-8. We review the mechanisms of H. pylori in enhanced gastric epithelial cell proliferation and cytokines in patients with H. pylori infection.

Viability and function of human sperm in electrolyte-free cold preservation

OBJECTIVE

To assess the viability and function of human sperm in electrolyte-free cold preservation.

DESIGN

Prospective comparative study.

SETTING

Andrology laboratory of our hospital.

PATIENT(S)

Ten semen samples obtained from patients attending our infertility clinic.

INTERVENTION(S)

Ejaculated sperm were washed using the electrolyte-free Percoll gradient and were then preserved in 0.33 M glucose solution, 0.16 M NaCl solution, 0.16 M KCl solution at 4 degrees C for 4 weeks. As a control, TEST (TES and Tris) yolk buffer (TYB) was added to the ejaculated semen and preserved at 4 degrees C.

MAIN OUTCOME MEASURE(S)

Sperm tail morphology, motility, viability (eosin-Y stain), and the concentration of adenosine triphosphate (ATP) were analyzed.

RESULT(S)

The number of sperm with normal tail form and the motility of sperm preserved in glucose solution (electrolyte-free cold preservation) were significantly (P < 0.01) higher for 4 weeks than those of sperm preserved in the other three media. The sperm viability in glucose solution was 75.5%, 65.4%, and 51.3%, after 1, 2, and 4 weeks, respectively. The ATP concentration after 1, 2, and 4 weeks remained 64.2%, 53.0%, and 4.3% of the prestorage value, respectively, in the sperm stored in glucose solution.

CONCLUSION(S)

The morphology, motility, viability, and ATP concentration of sperm in electrolyte-free cold preservation were substantially better than those in NaCl solution, KCl solution, or TYB for 2 weeks.

[Clinical experience of ileal neobladder for bladder cancer]

Between June 1993 and July 1996, an ileal neobladder was created in 20 patients after total cystectomy for bladder cancer. The mean post operative follow-up period was 32 months, with a range of 9 to 47 months. Ureteroileostomy was performed using the Le Duc-Camey procedure. There were 3 (15%) early postoperative complications, which were all of transient urine leakage from the neobladder. Late complications were encountered in 6 patients (30%), which were of stenosis of ureteroileal anastomosis in 2 (10%), stone in the neobladder in 2 (10%), neobladder-cutaneous fistula in 1 (5%) and neobladder-ureteral reflux in 1 (5%). Reoperation was necessary in 4 patients (20%); 2 for stenosis of ureteroileal anastomosis and 2 for removal of a stone in the neobladder. No urethral recurrence has been noted. Local recurrence occurred in 2 patients, who died of tumor progression 16 and 27 months postoperatively. All 20 patients were continent during the day time (100%), while 2 (10%) had nocturnal incontinence.

Increased expression of interleukin-1 beta and monocyte chemotactic and activating factor/monocyte chemoattractant protein-1 in the hypertrophied and failing heart with pressure overload

Studies on the effects of proinflammatory cytokines on the heart suggest that they play some roles in the pathogenesis of congestive heart failure (CHF). To determine the involvement of proinflammatory cytokine in cardiac hypertrophy and CHF induced by mechanical overload, we investigated the expression of interleukin (IL)-1 beta and monocyte chemotactic and activating factor (MCAF)/monocyte chemoattractant protein-1 (MCP-1) in the left ventricle (LV) of Dahl salt-sensitive (DS) rats that showed hypertrophy of the LV induced by hypertension and subsequently developed CHF. The IL-1 beta mRNA content in the LV of DS rats increased 3.9-fold when LV hypertrophy developed, and the increase reached 6.2-fold at the CHF stage compared with that of age-matched Dahl salt-resistant (DR) rats. The amount of IL-1 beta in the LV was positively correlated with the LV weight/body weight ratio. Most of the IL-1 beta immunoreactivity was localized in the endothelial cells and interstitial macrophages. The mRNA levels of MCAF in the LV increased 3.6-fold at 11 weeks and reached 4.8-fold at the CHF stage relative to the age-matched DR rats. MCAF protein was localized to the endothelial cells and interstitial macrophages. In DS rats, the number of interstitial macrophages increased diffusely throughout the LV. We suggest that increased chemokine expression, macrophage infiltration, and proinflammatory cytokine expression play some role in the pathogenesis of cardiac hypertrophy and failure induced by chronic mechanical overload.

Primary tracheal fibrosarcoma in a child: a case of tracheal resection under ECMO support

We report a case of severe airway obstruction due to endotracheal fibrosarcoma in a 3-year-old boy. Successful tracheal resection and reconstruction was performed under extracorporeal membrane oxygenation support. A solid, elastic hard tumor with a smooth surface was attached by a tiny stalk structure to the membranous part of the lower trachea. Histological findings of the tumor were consistent with infantile fibrosarcoma, showing proliferation of spindle cells forming interlacing patterns.

Role of acetylcholine and gastrin-releasing peptide (GRP) in gastrin secretion

Using an isolated rat stomach infusion model, we investigated the role of gastrin-releasing peptide (GRP) and acetylcholine in the secretion of gastrin (which plays a major role in gastric acid secretion), and the relationship between gastrin secretion and stomach pH. Bombesin, which has a structure analogous to that of GRP, was used in the experiment. We also investigated whether acetylcholine has muscarine-like or nicotine-like action. Our findings pointed to the presence of an alternative, GRP-mediated, route for stimulating gastric secretion from G cells, other than the acetylcholine-mediated route. We injected bombesin to confirm the presence of such a GRP-mediated route; significantly increased gastrin secretion was observed, even under acidic conditions, in the gastric lumen, which has been considered to show almost no gastric secretion. This secretion was not inhibited by atropine. The results suggested that there are two routes for inducing gastrin secretion from G cells: an acetylcholine-mediated route and a GRP-mediated route (intramural peptide neurons). As GRP induced gastrin secretion, regardless of stomach pH, GRP was considered to be more closely related to gastrin secretion. The results also suggested that a muscarine-like action, particularly in the M3 receptor-mediated route, plays a significant role in acetylcholine-mediated gastrin secretion and that nicotine-like action is not involved in gastrin secretion.

The tumor-derived fetal-intestinal alkaline phosphatase cDNA is identical in sequence to the adult intestinal alkaline phosphatase isozyme gene

The alkaline phosphatase (AP) of Caco-2 cells, a cell line derived from a human adenocarcinoma of the colon, is quite similar to fetal intestinal AP in its enzymatic properties. The nucleotide sequence of a cDNA encoding AP produced in Caco-2 cells was examined. The sequence was identical to one of the three sequences of adult intestinal AP reported previously. We further investigated the entire nucleotide sequence of cDNA of intestinal-type AP produced in cancer cell lines such as HuH-7 cells, FL-amnion cells, and HuG-1 cells. The sequence of these cell APs was identical to that of Caco-2 cell AP. These results indicate that cancer cells producing intestinal-type AP have the same nucleotide sequence as that of adult intestinal AP, and suggest that the differences in electrophoretic mobilities of these cell APs compared with adult intestinal AP may be due to post-translational modifications.