Biomedical subjects
Publications and source records attributed to M Umeda.
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A retrospective study was made of the correlation between preoperative clinical or histologic findings and the prevalence of lymph node metastasis in 60 patients with squamous cell carcinoma of the oral cavity who had histologically confirmed neck metastasis. Of these 60 patients, 39 with clinically N+ necks underwent immediate therapeutic neck dissection, and 21 whose necks were initially N0 but progressed to N+ during observation underwent subsequent therapeutic neck dissection. The primary site, TNM staging, histologic grade of malignancy of biopsy specimen, and location and number of histologically positive lymph nodes were reviewed in each case. The results were as follows: (1) The prevalence of neck metastasis was not significantly correlated with primary site and T stage; however, there was an apparent correlation between histologic grade of malignancy and the prevalence of neck metastasis. Patients with grade I-II histologic malignancy showed limited metastases that involved lymph nodes in levels I-II. On the other hand, patients showing grade III-IV histologic malignancy often had metastases that extended beyond level III, regardless of T stage. These results suggest that histologic grade of malignancy, as well as clinical features, must be taken into consideration when deciding whether supraomohyoid neck dissection is indicated. (2) The group that underwent subsequent neck dissection exhibited less advanced neck metastasis and a better prognosis than the group which underwent immediate neck dissection. These findings show that if they are closely followed up, it is possible to delay neck dissection in N0 patients until a neck metastasis is detected.
Brain edema can be classified into three categories: vasogenic, cytotoxic, and interstitial. The mechanism of edema is thought to be different in each type. The authors studied the movement of water molecules in each type of white matter edema in a rat model by using diffusion-weighted magnetic resonance imaging. Conventional T2-weighted imaging did not allow distinction between the three types of white matter edema; the three types of edema were, however, distinguished by using diffusion-weighted imaging. The apparent diffusion coefficient (ADC) of water was different in each type of edema. Water molecules in cytotoxic edema induced by triethyl-tin intoxication showed a smaller and less anisotropic ADC than in normal white matter. In contrast, water in vasogenic edema induced by cold injury had a larger and more anisotropic ADC than in normal white matter. Water in interstitial edema due to kaolin-induced hydrocephalus had an anisotropic and very large ADC.
Two in vitro experimental systems were compared to evaluate the pharmacological effects of some herbal medicines on the biotransformation of arachidonic acid (AA) using the microsomal fraction of sheep vesicular glands as an enzyme source. The first system involved the addition of serum obtained from rats treated orally with the herbal medicines, while the second system involved the direct addition of herbal medicine extracts to the enzyme medium. Both systems were performed in parallel. Indomethacin, used as a reference drug, inhibited AA biotransformation in a dose-dependent manner in both experimental systems. The serum of rats orally pretreated for 1 h with Coptis japonica rhizome and Paeonia lactiflora root also inhibited AA biotransformation. Direct addition of hot water extracts of Rheum officinale rhizome, Scutellaria baicalensis root, Paeonia moutan bark and Zingiber officinale rhizome also inhibited AA biotransformation, while the extracts of Coptis japonica rhizome and Paeonia lactiflora root showed no effects.
Endogenous prostaglandins (PGs) play an important role in the cytoprotective and healing responses in the stomach, by altering various functions, i.e., an increase of the mucosal blood flow, yet the role of prostacyclin (PGI(2)) and its receptor (IP-receptor) in these responses remains unclarified. In the present study, we used IP-receptor knockout mice [IP (-/-)] and examined the importance of IP-receptors in gastric ulcerogenic, cytoprotective and healing responses in these animals. The studies included the ulcerogenic response to cold-restraint stress, the cytoprotective response to a mild irritant (20 mM taurocholate: TC) and capsaicin, and the healing response of chronic gastric ulcers induced by thermo-cauterization. We first checked the absence of IP-receptors by examining the effect of cicaprost (a PGI(2) agonist, topical mucosal application) on gastric mucosal blood flow and found that this agent increased the mucosal blood flow in wild-type [WT (+/+)] mice but not in IP (+/-) mice. Cold-restraint stress (4 h) induced gastric lesions in both groups of mice, but the severity of damage was significantly greater in IP (-/-) mice. Prior p.o. administration of both TC and capsaicin exhibited a marked cytoprotection against HCl/ethanol-induced gastric damage in WT (+/+) mice, both responses being significantly mitigated in the presence of indomethacin. The adaptive cytoprotection induced by TC was similarly observed in IP (-/-) mice, while the capsaicin protection was totally attenuated in the animals lacking IP receptors. On the other hand, the healing of gastric ulcers was significantly delayed by daily administration of indomethacin in WT (+/+) mice. However, this process was not altered in IP (-/-) mice. These results suggest that endogenous PGI(2) is involved in the gastric ulcerogenic response to stress, but not in the healing of pre-existing gastric ulcers. In addition, PGI(2) and its receptors may play a crucial role in capsaicin-induced gastric protection but not in the adaptive cytoprotection-induced by mild irritants.
To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection.
Serum (beta 1-->3)-D-glucan was elevated in 34 of 126 patients (27%) with hematologic malignancy who were clinically suspected of having a deep-seated mycosis. Although 11 patients (8.8%) were thought to have fungemia, fungi were isolated from blood culture in only 4. These results suggest that measurement of serum beta-D-glucan is useful for early diagnosis. Therapy with fluconazole (FLCZ) was effective in 9 of 11 patients (81.8%) suspected of having fungemia. Fungemia responded in 5 of 7 patients who were given granulocyte-colony-stimulating factor (G-CSF) concomitantly with FLCZ. This result suggested that administration of G-CSF with FLCZ was useful therapy for fungemia, which may occur during granulocytopenia following chemotherapy with anticancer agents.