A cost-minimization analysis of measures against metallic dental restorations for head and neck radiotherapy

The aim of this study was to compare the estimated public medical care cost of measures to address metallic dental restorations (MDRs) for head and neck radiotherapy using high-energy mega-voltage X-rays. This was considered a first step to clarify which MDR measure was more cost-effective. We estimated the medical care cost of radiotherapy for two representative MDR measures: (i) with MDR removal or (ii) without MDR removal (non-MDR removal) using magnetic resonance imaging and a spacer. A total of 5520 patients received head and neck radiation therapy in 2018. The mean number of MDRs per person was 4.1 dental crowns and 1.3 dental bridges. The mean cost per person was estimated to be 121 720 yen for MDR removal and 54 940 yen for non-MDR removal. Therefore, the difference in total public medical care cost between MDR removal and non-MDR removal was estimated to be 303 268 800 yen. Our results suggested that non-MDR removal would be more cost-effective than MDR removal for head and neck radiotherapy. In the future, a national survey and cost-effectiveness analysis via a multicenter study are necessary; these investigations should include various outcomes such as the rate of local control, status of oral mucositis, frequency of hospital visits and efforts of the medical professionals.     

Clinical application of18F-FUdR in glioma patients — PET study of nucleic acid metabolism

Summary Positron emission tomography was used to investigate the metabolism of nucleic acids by¹⁸F-fluoro-2-deoxyuridine (¹⁸F-FUdR) in 22 patients with gliomas. Sixteen cases of high grade glioma clearly demonstrated a region of high activity with a differential absorption rate (DAR) of 0.64 ± 0.34. Six cases of low grade glioma failed to reveal a positive image of the tumor and the DAR in tumor was 0.21 ± 0.042 (p < 0.01). This PET-¹⁸F-FUdR study succeeded in differentiating high and low grade gliomas from the view point of nucleic acid metabolism.     

Anterior Transhepatic Approach for Isolated Resection of the Caudate Lobe of the Liver

RID=" ID=" <E5>Correspondence to:</E5> J. Yamamoto, M.D.     

Activation of the reticulothalamic cholinergic pathway by the major metabolites of aniracetam

The aim of the study was to further investigate the effects of aniracetam, a cognition enhancer, and its metabolites on the brain cholinergic system. We measured choline acetyltransferase activity and acetylcholine release using in vivo brain microdialysis in stroke-prone spontaneously hypertensive rats (SHRSP). The enzyme activity in the pons–midbrain and hippocampus, and basal acetylcholine release in the nucleus reticularis thalami were lower in SHRSP than in age-matched Wistar Kyoto rats, indicating central cholinergic deficits in SHRSP. Repeated treatment of aniracetam (50 mg/kg p.o.×11 for 6 days) preferentially increased the enzyme activity in the thalamus, whereas decreased it in the striatum. Among the metabolites of aniracetam, local perfusion of N-anisoyl-γ-aminobutyric acid (GABA, 0.1 and/or 1 μM) and p-anisic acid (1 μM) into the nucleus reticularis thalami, dorsal hippocampus and prefrontal cortex of SHRSP produced a significant but delayed increase of acetylcholine release. We failed, however, to find any effect of aniracetam itself. A direct injection of N-anisoyl-GABA (1 nmol) into the pedunculopontine tegmental nucleus of SHRSP enhanced the release in the nucleus reticularis thalami. Thus, these data prove that aniracetam can facilitate central cholinergic neurotransmission via both metabolites. Based on its pharmacokinetic profile, N-anisoyl-GABA may contribute to the clinical effects of aniracetam, mainly by acting on the reticulothalamic cholinergic pathway.     

Basic FGF partially prevents degeneration of paraventricular vasopressin neurons after hypophysectomy

Invading and resident macrophages were studied in the regenerating rat vagus nerve in vivo and in vitro, using antibodies to invading (EDI) and resident (ED2) macrophages. Fresh vagus nerves contained no EDI positive macrophages as revealed by immunocytochemical staining. In crush lesioned nerves in vivo, the number of EDI positive cells around and distal to the crush lesion, increased dramatically with time. Interestingly, EDI positive cells, although few, appeared in the cultured vagus nerves subjected to a crush lesion. Resident ED2 positive macrophages were abundant in fresh nerves. In vivo, there was a small increase of ED2 positive macrophages at the crush area as regeneration proceeded. In contrast, no increase was observed in vitro and after 3 days no ED2 stained macrophages were found. Immunocytochemical staining for low-affinity NGF-receptors showed a dramatic increase at the crush and distal to it in vivo, while in vitro, the receptors were upregulated along the entire nerve. The results suggest that invading macrophages may not be crucial for the initial and early outgrowth of sensory nerve fibres in peripheral nerves.     

Role of Ca2+-activated K+ channels in acetylcholine-induced dilatation of the basilar artery in vivo

1. We tested the hypothesis that activation of large conductance calcium-activated potassium channels is involved in dilator responses of the basilar artery to acetylcholine in vivo. Using a cranial window in anaesthetized rats, we examined responses of the basilar artery to acetylcholine.
2. Topical application of acetylcholine (10⁻⁶ and 10⁻⁵ M) increased diameter of the basilar artery from 238±7 μm to 268±7 and 288±7 μm, respectively (P<0.05 vs. baseline diameter). Iberiotoxin (10⁻⁸ M), an inhibitor of large conductance calcium-activated potassium channels, did not affect baseline diameter of the basilar artery. In the presence of 10⁻⁸ M iberiotoxin, 10⁻⁶ and 10⁻⁵ M acetylcholine increased diameter of the basilar artery from 239±7 μm to 246±7 and 261±7 μm, respectively. Thus, iberiotoxin attenuated acetylcholine-induced dilatation of the basilar artery (P<0.05).
3. Sodium nitroprusside (10⁻⁷ and 10⁻⁶ M) increased diameter of the basilar artery from 242±9 μm to 310±12 and 374±13 μm, respectively (P<0.05 vs. baseline diameter). In the presence of iberiotoxin (10⁻⁸ M), sodium nitroprusside (10⁻⁷ and 10⁻⁶ M) increased diameter of the basilar artery from 243±6 μm to 259±9 and 311±12 μm, respectively. Thus, iberiotoxin attenuated dilator responses of the basilar artery to sodium nitroprusside (P<0.05).
4. Iberiotoxin partly inhibited dilator responses of the basilar artery to forskolin, a direct activator of adenylate cyclase, but did not affect vasodilatation produced by levcromakalim, a potassium channel opener.
5. These results suggest that dilator responses of the basilar artery to acetylcholine and sodium nitroprusside are mediated, in part, by activation of large conductance calcium-activated potassium channels. Because both acetylcholine and sodium nitroprusside have been shown to activate guanylate cyclase via nitric oxide, activation of large conductance calcium-activated potassium channels may be one of the major mechanisms by which cyclic GMP causes dilatation of the basilar artery in vivo.

     

Vasoformative sarcomas arising from BALB/3T3 cells attached to solid substrates.

The BALB/3T3 mouse embryo cell line, noted for its marked postconfluence inhibition of proliferation, anchorage dependence, and high serum requirement, and frequently studied as a prototype nontumorigenic "fibroblast" line that is compared with tumorigenic sublines transformed with various agents, produced tumors within 2 to 3 months when an average of 3 X 10(4) cells were implanted s.c. attached to 1- X 5- X 10-mm polycarbonate platelets. Plastic platelets alone produced no tumors after 1 year of observation. The tumors, as well as others arising from implants of BALB/3T3 cells attached to 3-mm glass beads, were given the histological diagnosis of "vasoformative saroma" because the tumor cells frequently formed vascular channels. The vasoformative pattern and the results of specific staining for reticulin and collagen support the likelihood that BALB/3T3 cells originated from endothelial cells rather than from fibroblasts. That the tumors were derived from BALB/3T3 cells and not host cells was proved when tumors arising in BALB/c X C57BL/6 F1 hybrids were shown to be transplantable to BALB/c but not to C57BL/6 mice. The cultured tumor cells showed loss of both postconfluence inhibition of proliferation and anchorage dependence. Evidence of the induction of endogenous oncornaviruses was obtained in only one of four tumors tested. These tumors also exhibited tumor-unique transplantation rejection antigens. We conclude that BALB/3T3 cells are preneoplastic and give rise to different spontaneously transformed clones bearing unique tumor rejection antigens when implanted in vivo attached to a solid substrate.     

Management of Hyperthyroidism Due to Graves' and Nodular Diseases

Endocrine surgeons have had an important role in the management of hyperthyroidism due to either Graves' disease or toxic nodule(s). Since alternative treatments such as antithyroid drugs or radioiodine are also available, the decision-making for management should be based on clear assessment of advantages and limitations of each of the treatment options. Surgery provides rapid resolution of these conditions, and cure rates are high, although it may be associated with perioperative complications and postoperative thyroid dysfunction. The authors' experience in the surgical treatment of hyperthyroidism and a review of the recent literature are outlined in this report.     

Primary Endodermal Sinus Tumor of the Vulva: A Case Report and Review of the Literature

Background.Extragonadal endodermal sinus tumors arising in the external genitalia represent an exceedingly rare malignancy in women. Six cases of endodermal sinus tumors of the vulva have been reported to date, with three cases failing to respond to conservative surgery and vincristine-based chemotherapy. We report a seventh case of vulvar endodermal sinus tumor that was treated with radical surgery and platinum-based chemotherapy.Case.RT is an 18-year-old female who presented with a vulvar mass that was diagnosed as endodermal sinus tumor at the time of biopsy. She was subsequently treated with modified radical vulvectomy and ipsilateral groin lymphadenectomy, followed by bleomycin, etoposide, and cisplatin chemotherapeutic regimen. She has since remained free of disease for 18 months as evidenced by serum α-fetoprotein and physical exam at 18 months.Conclusions.Vulvar endodermal sinus tumors represent a very small number of germ cell tumors in women. Based on the previous accounts, this disease appears to be more fatal than endodermal sinus tumor arising at other sites. These tumors also have a predilection for local metastasis. Due to the previous accounts, we chose to treat this patient with radical surgery and platinum-based chemotherapy. This treatment regimen has resulted in a disease-free state for 18 months.