C CELL CARCINOMA OF THE THYROID

Two cases of papillary type of C cell carcinoma of the thyroid were reported. They showed papillary arrangement with Abrovascular stalk in properly Axed tissues. Histochemically argyrophil reaction was positive in the cytoplasm and amyloid deposited in the stroma. Ultrastructurally secretory granules were found in their cytoplasm. The papillary type is not an artifact but one of the histologic variations of this carcinoma. ACTA PATH. SAP. 29: 653–659, 1979.     

Modifying effects of 1'-acetoxychavicol acetate (ACA) and the novel synthetic retinoids Re-80, Am-580 and Am-55P in a two-stage carcinogenesis model in female rats

Effects of dietary administration of 1'-acetoxychavicol acetate (ACA) and the novel synthetic retinoids 4-[1-hydroxy-3-oxo-3-(5,6,7,8-tetrahydro-3-hydroxy-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid (Re-80); 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carboxamido]benzoic acid (Am-580); and 6-[(3,5-di-tert-butylphenyl) carbamoyl]nicotinic acid (Am-55P) were examined using a two-stage rat carcinogenesis model. A total of 190 female SD rats was treated sequentially with 1,2-dimethylhydrazine (DMH, s.c.); 7,12-dimethylbenz(a)anthracene (DMBA, i.g.); and 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN, in the drinking water) during the first three weeks (DDD-initiation), and an additional 60 rats received the vehicle alone (non-initiation). One week after the completion of the initiation period, they were divided into nine groups and administrated Re-80 (at dose levels of 1.0 or 0.4 ppm), Am-580 (20 or 4 ppm), Am-55P (20 ppm), ACA (100 ppm), all-trans-retinoic acid (10 or 2 ppm) or no supplement in the diet for 33 weeks, until survivors were euthanatized at week 37 weeks. After DDD-initiation, all-trans-retinoic acid at the high dose delayed the development of mammary tumors. The multiplicity of colon tumors in the group fed Am-55P and the incidences of nephroblastomas with ACA or Am-580 were decreased as compared with the control values, but the other chemicals had no modifying effects on tumor development in any organs. Thus, among ACA and the novel synthetic retinoids tested, only Am-55P showed a weak inhibitory effect on a neoplasm of general interest under the present experimental conditions.     

The investigation of isoflurane therapy for status asthmaticus patients]

Status asthmaticus is defined as an attack of bronchial asthma that resists conventional treatment and continues for more than 24 hours. We report here about patients with status asthmaticus who were successfully treated with isoflurane inhalation. Of the 19 patients who were transferred to the intensive care unit (ICU) and underwent mechanical ventilation from January 1996 to May 2001, eleven patients who were first treated by isoflurane inhalation were targeted in this study. Their improvement was assessed 6 and 24 hours after anesthesia compared with their condition before anesthesia. The tidal volume, pH, and PaCO2 improved within 6 hours after anesthesia. For the next step, among the patients who were transferred to the critical care center soon after an attack of bronchial asthma and underwent mechanical ventilation, 8 patients who were treated by isoflurane inhalation anesthesia (Group I) and another 4 patients who were not treated by isoflurane (Group NI) were compared to assess the usefulness of isoflurane inhalation therapy. The patients in Group I stayed in the ICU and underwent mechanical ventilation for a shorter period. These patients had hypotension and liver dysfunction after the inhalation anesthesia, but these symptoms were improved by decreasing the concentration of isoflurane. Isoflurane inhalation therapy seemed useful for intractable status asthmaticus, and earlier introduction of this therapy is expected to achieve a greater therapeutic effect.     

Apoptotic body engulfment by a human stellate cell line is profibrogenic

Hepatocyte apoptosis and stellate cell activation are both features of chronic liver diseases, but a relationship between these events has not been explored. In macrophages, engulfment of apoptotic bodies induces expression of transforming growth factor-beta (TGF-beta), a profibrogenic cytokine. We examined whether a similar response occurs in stellate cells. Fluorescently labeled hepatocyte apoptotic bodies were added to cultures of primary and immortalized human stellate cells. Stellate cells, but not hepatocytes, readily engulfed apoptotic bodies in a time-dependent manner as assessed by confocal microscopy. The activation of primary and immortalized human stellate cells after incubation with apoptotic bodies, as well as their fibrogenic activity, was indicated by an increase in alpha-smooth muscle actin (primary cells), TGF-beta1, and collagen alpha1(I) mRNA (primary and immortalized cells). The profibrogenic response was dependent upon apoptotic body engulfment, because nocodazole, a microtubule-inhibiting agent, blocked both the engulfment and the increase of TGF-beta1 and collagen alpha1(I) mRNA. As described in primary rodent stellate cells, up-regulation of collagen alpha1(I) mRNA was inhibited by a PI-3K inhibitor (LY294002) and a p38 mitogen-activated protein kinase inhibitor (SB203580) in LX-1 cells. In conclusion, these data support a model in which engulfment of hepatocyte apoptotic bodies by stellate cells leads to a fibrogenic response by eliciting a kinase-signaling pathway.     

Experimental and clinical aspects of oxidative stress and redox regulation

Although excess amounts of oxidative stress damage proteins and nucleotides, small amounts of oxidative stress transduce intracellular signals for cellular activation, differentiation and proliferation. Reduction/oxidation(redox) regulation is defined as a biological response to maintain homeostasis against oxidative stress. Thioredoxin, a 12 kD small protein with a redox-active dithiol/disulfide in the conserved active site: -Cys-Gly-Pro-Cys-, is a key molecule for redox regulation as well as glutathione(GSH). Thioredoxin is induced by a variety of oxidative stresses and secreted from cells. Thioredoxin plays crucial roles as a redox-regulator of intracellular signal transduction and as a radical scavenger. Plasma levels of thioredoxin are good biomarkers for oxidative stress. Thioredoxin-transgenic mice are more resistant to cerebral infarction, infection or inflammation and survive longer than control mice. Administration of thioredoxin may have a good potential for anti-aging and anti-stress effects. Redox regulation mechanisms by thioredoxin and other thioredoxin family members will clarify the pathophysiology of oxidative stress-associated disorders.     

Thioredoxin and its related molecules: update 2005

Studies on thioredoxin (Trx) and its related molecules have expanded dramatically recently. Proteins that share the similar active-site sequence, -Cys-Xxx-Yyy-Cys-, are called the Trx family, and the number of Trx family members is increasing. Trx reductase, which reduces oxidized Trx in cooperation with NADPH, has three isoforms, and peroxiredoxin, which is Trx-dependent peroxidase, has six isoforms. In addition to a role as an antioxidant, Trx and its related molecules play crucial roles in the redox regulation of signal transduction. The classical cytosolic Trx1 and truncated Trx80 are released from cells. Plasma/serum levels of Trx1 are good markers for oxidative stress. Exogenous Trx1 shows cytoprotective and antiinflammatory effects and has a good potential for clinical application. This is an update review on Trx and its related molecules.     

Primary anorectal malignant melanoma: Report of a case

(Received for publication on Aug. 18, 1997; accepted on May 15, 1998)     

The ultrastructure of parapapillary chorioretinal atrophy in eyes with secondary angle closure glaucoma

Background: The present study was performed to investigate the ultrastructure of deep retinal layers and choroid corresponding to the parapapillary chorioretinal atrophy in eyes with secondary angle-closure glaucoma. Methods: The glaucomatous eyes included two eyes enucleated due to iris ring melanoma with high intraocular pressure and one eye with neovascular glaucoma enucleated due to ocular pain. The control eyes included one eye enucleated due to choroidal malignant melanoma with normal intraocular pressure and one eye enucleated during surgery for supramandibular carcinoma. These eyes were studied with light and electron microscopy. Results: In the region of parapapillary chorioretinal atrophy of glaucomatous eyes, the retinal pigment epithelial cells showed degenerative changes, such as loss of basal in foldings and microvilli, degenerated mitochondria, vacuolar degeneration and irregular distribution of melanin granules. The photoreceptors were decreased in number in this area of glaucomatous eyes. The lumen of the choriocapillary vessels adjacent to the optic nerve was collapsed. Conclusion: These results elucidate the fine structures of deep retina and choroid in the region of parapapillary chorioretinal atrophy of glaucomatous eyes, and suggest that the reduced choroidal perfusion might be the pathogenetic mechanism of glaucomatous parapapillary chorioretinal atrophy.     

Autologous mixed lymphocyte reaction and postoperative prognosis in patients with gastric carcinoma

The autologous mixed lymphocyte reaction (AMLR) represents a self recognitive response, which is very important in the immunoregulatory network system. We investigated whether the AMLR activity of patients with gastric carcinoma could reflect the postoperative prognosis to clarify the significance of autoreactivity in anti-tumor immune system in cancer patients. The AMLR activity was suppressed both in the peripheral blood and in the spleen of patients with gastric carcinoma. The patients were divided into two groups; high responder and low responder group. The former consisted of patients whose AMLR activity was extremely suppressed, and the latter of patients whose AMLR activity was mildly suppressed. The survival rate and disease-free survival rate were generally higher in the high responder group than in the low responder group, especially in the spleen. Moreover, none of the patients in the high responder group for the AMLR activity in the spleen died within three years. These results indicated that the AMLR activity could reflect the prognosis of patients who received conventional curative operation. Therefore, it was suggested that the AMLR might be a useful parameter of postoperative prognosis in gastric cancer patients and that autoreactive T cells might play a pivotal role in auto-specific immunological control of tumor growth and metastases.     

Use of YAG laser combined with mucosal suturing for the treatment of polypoid vocal cord]

To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases.