[Thyroid function in patients with anorexia nervosa and depression]

Thyroid hormone levels were measured in 21 patients with anorexia nervosa, 15 patients with depression and 16 patients with severe depression and were compared with those in 53 normal subjects. In anorexia nervosa and severe depressed patients, serum T3, T4, fT3, fT4 and T3/T4 ratio showed significantly lower values than those in normal subjects. However there was no difference between depressed patients and normal subjects. The serum TSH levels were within normal range in all of the studied subjects. Thus, thyroid hormone levels in severe depressed patients were similar to those in anorexia nervosa and the changes were inversely related to disease conditions. The supplementation of thyroid hormones to antidepressant relieved clinical symptoms in some of the severe depressed patients. These results suggested that the changes in thyroid hormone levels in anorexia nervosa and severe depression were mainly due to impaired conversion of T4 to T3 by increased cortisol secretion through emotional stress.

Radioprotection by WR-151327 against the late normal tissue damage in mouse hind legs from gamma ray radiation

PURPOSE

To evaluate the protective effect of WR-151327 on late radiation-induced damage to normal tissues in mice.

METHODS AND MATERIALS

The right hind legs of mice with or without WR-151327 administration (400 mg/kg) were irradiated with 137Cs gamma rays. Leg contracture and skin shrinkage assays were performed at 380 days after irradiation. The mice were killed on day 400 postirradiation and histological sections of the legs were made. The thickness of the dermis, epidermis, and skin (dermis plus epidermis) was measured. The muscular area of the legs and the posterior knee angle between the femur and tibia were also measured. The left hind legs were similarly assessed as nonirradiated controls. Group means and standard deviations were calculated and dose-response curves were drawn for every endpoint. Then, the dose modifying factor (DMF) for each endpoint and the correlations among endpoints were determined.

RESULTS

Late damage assayed by leg contracture and skin shrinkage progressed with increasing radiation dose. However, it was reduced by drug treatment. The significant effect was indicated for skin shrinkage by a DMF of 1.8 at 35%. The DMF for leg contracture was 1.3 at 6 mm. In the irradiated legs, epidermal hyperplasia and dermal fibrosis in the skin, muscular atrophy, and extension disturbance of the knee joint were observed. These changes progressed with increasing radiation dose. Skin damage assayed by the present endpoints was also reduced by drug treatment by DMFs of 1.4 to 1.7. However, DMFs for damage to the muscle and knee were not determined because no isoeffect was observed. There were good correlations between leg contracture or skin shrinkage and the other endpoints in both untreated and drug-treated mice.

CONCLUSIONS

WR-151327 has the potential to protect against radiation-induced late normal tissue damage.

Characterization of three different transgenic mouse lines that carry human poliovirus receptor gene--influence of the transgene expression on pathogenesis

Three transgenic mouse lines, ICR-PVRTg1, ICR-PVRTg5, and ICR-PVRTg21, which are susceptible to poliovirus, have been established by introducing the human gene for poliovirus receptor (PVR) into the genome of mouse strain ICR. Genetic characterizations of the PVR gene were carried out on these mouse lines to define the approximate copy number, insertion site, and expression of the transgene in the central nervous system (CNS). The transgene was integrated in the chromosome 4, 12, and 13 of ICR-PVRTg1, ICR-PVRTg5 and ICR-PVRTg21 mice, respectively, and was stably transmitted to progeny mice. ICR-PVRTg1 appeared to have the most abundant copy numbers of the transgene and showed the highest level of PVR mRNA and membrane associated PVR protein in the CNS among the three mouse lines. Those in ICR-PVRTg21 and ICR-PVRTg5 were at intermediate and lowest levels, respectively. In the CNS, PVR mRNA was detected at high levels only in neurons of the spinal cord and brain stem where poliovirus can replicate, suggesting that the PVR mRNA expression confers cell specificity to poliovirus in the CNS. ICR-PVRTg1 and ICR-PVRTg5 showed the highest and the lowest sensitivity to poliovirus, respectively, whereas ICR-PVRTg21 was in-between. These results may suggest that poliovirus sensitivity of the mice is attributed to relative levels of PVR expression.

[Changes of thyroid hormone levels during ACTH therapy in epileptic children]

To investigate the effect of ACTH on thyroid function, thyroid hormone levels were measured in twelve patients with epileptic children who were treated with ACTH. One week after daily administration of ACTH, serum T3, T4, TSH, thyroglobulin and T3/T4 ratio showed significantly lower values compared with those of pretreatment values (p < 0.001-p < 0.05). Thyroid hormone levels respectively showed negative correlation with cortisol levels before and one week after ACTH treatment respectively. Tapering of ACTH brought a rapid recovery of T3, T4, TSH and thyroglobulin levels with concomitant return of plasma cortisol levels to the normal range. These results suggested that excess ACTH suppressed thyroid hormone secretion mainly through a decreased TSH secretion and a peripheral conversion of T4 to T3 by increased cortisol levels.

Accelerated bone marrow recovery from radiation damage in etoposide-pretreated mice

PURPOSE

Etoposide inhibits the activity of Topoisomerase II, and possesses radiosensitizing effects on cultured cells. We showed that pretreatment of mice with etoposide 1 day before whole-body irradiation (WBI) had a protective effect against radiation-induced bone marrow death. The number of endogenous colony-forming units (CFU-S) surviving in WBI mice was significantly increased by pretreatment with etoposide. The purpose of the present study is to clarify mechanisms underlying the protective activity of etoposide against radiation-induced bone marrow damage.

METHODS AND MATERIALS

The spleen colony-forming cells (CFU-S) of femoral marrow were assayed by the method of Till and McCulloch. The proliferative state of CFU-S was assessed using the technique of Hodgson. The reduction in exogenous CFU-S after hydroxyurea injection was used to determine the fraction size of S-phase in CFU-S.

RESULTS

Etoposide pretreatment did not modify the cell survival parameters of exogeneous CFU-S when bone marrow cells were assayed immediately after WBI. Recovery of CFU-S in femoral marrow started earlier in mice receiving etoposide pretreatment than in the radiation alone group. Administration of hydroxyurea revealed that the accelerated recovery of CFU-S was due to an increased population of S phase cells, suggesting etoposide pretreatment shortened generation time of CFU-S.

CONCLUSIONS

The mechanism for the radioprotection appears to be accelerated proliferation of survived bone marrow cells rather than a change in cellular sensitivity to radiation.

Cell- and stage-specific expression of basic FGF in the developing rat gonads

In order to clarify the participation of basic fibroblast growth factor (bFGF) in rat gonadal differentiation and development, immunohistochemical localizations of bFGF were chronologically studied in Sprague-Dawley rat gonads from gestational day (GD) 13 to postnatal day (PD) 21 by using avidin-biotin complex technique. Immunohistochemical reactivity to bFGF antibody was positive in the germ cells. Slight or moderate immunostaining was seen in male germ cells from GD 18 to PD 5, and in female germ cells from PD 5 to 21. Leydig/interstitial cells in male gonads were slightly or moderately stained from GD 16 to PD 21. On the other hand, other types of gonadal cells were not stained during the perinatal period. These results indicate that bFGF shows discrete cell- and stage-specific patterns of expression in gonads during the perinatal period and is likely to participate in control of gonadal development in rats.

The radiosensitivity of quiescent cell populations in murine solid tumors in irradiation with fast neutrons

PURPOSE

We analyzed the characteristics of radiosensitivity and potentially lethal damage repair in the quiescent cell populations of murine SCC VII solid tumors irradiated with fast neutrons, in comparison with those irradiated with 10 MV X rays.

METHODS AND MATERIALS

SCC VII tumor-bearing C3H/He mice were irradiated with 30 MeV fast neutrons or 10 MV X rays after receiving 10 injections of 5-bromo-2'-deoxyuridine (BUdR) to label all proliferating tumor cells. Immediately or 24 h after irradiation, the tumors were excised and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus frequency in cells without BUdR labeling was determined using immunofluorescence staining to BUdR. This micronucleus frequency was then used to calculate the surviving fraction of unlabeled cells from the regression line for the relation between micronucleus frequency and the surviving fraction of all tumor cells. Thus, a cell survival curve could be determined for the cells not labeled by BUdR, which can be regarded as the quiescent cells for all practical purposes.

RESULTS

The difference in intrinsic radiosensitivity between all tumor and quiescent cells became smaller by using fast neutrons, compared with X rays, especially when large radiation doses were given. Potentially lethal damage repair by quiescent cells was less evident following irradiation with fast neutrons than with X rays, especially when large doses were delivered.

CONCLUSION

By using fast neutrons in clinical radiotherapy, the radiosensitivity of solid tumors is thought to depend on their heterogeneity less critically than for X rays.

A murine model for bone marrow metastasis established by an i.v. injection of C-1300 neuroblastoma in A/J mice

A reproducible tumor model for bone marrow metastasis has been developed by an injection of murine C-1300 neuroblastoma (C-1300 NB) cells into the tail vein of syngeneic A/J mice. The animals died with liver metastases at 18-21 days after an injection of 10(5) tumor cells and often had bone marrow metastasis in the femur. N-methylformamide (NMF), a maturational agent, was administered to inhibit liver metastases and to extend survival in mice with advancing bone metastasis. Histological examination of bone marrow metastasis, demonstrated lesions varying from a few small colonies of C-1300 NB cells either in metaphysis or diaphysis to large foci replacing normal hematopoietic bone marrow, simultaneously invading epiphysis or cortex of bone as bone metastasis. This assay demonstrated the ability to detect neuroblastoma cells in the bone marrow histologically and could determine bone marrow TD50 by extraction of bone marrow cells after treatment with various doses of drug. Fifty per cent of mice injected with cyclophosphamide (CY) developed bone marrow metastasis without liver metastasis. Treatment with tamoxifen, an anti-calmodulin drug, suppressed tumor takes in the recipient mice with tamoxifen-dose-dependent fashion. This experimental system allows for investigations into the therapeutic response and biology of neuroblastoma metastases in the bone marrow.

Hair fibrous protein compositions in some hereditary hair abnormalities determined by two-dimensional polyacrylamide gel electrophoresis

S-carboxymethylated (SCM) fibrous proteins (FPs) from the scalp hairs of the three different hereditary hair abnormalities (trichorrhexis invaginata in Netherton's syndrome, pili trianguli et canaliculi in uncombable hair syndrome, and fine hair in anhidrotic ectodermal dysplasia) were analyzed by two-dimensional polyacrylamide gel electrophoresis. Comparison of the SCM FP compositions of the three hair abnormalities with that of the normal revealed that the SCM FP compositions of these three abnormal hairs were all electrophoretically different from each other and that of the normal.

Amino acid residues on human poliovirus receptor involved in interaction with poliovirus

We have previously demonstrated that the N-terminal immunoglobulin-like domain (domain 1; 115 amino acids) of human poliovirus receptor (hPVR) is essential for poliovirus binding and infection to cells. To identify amino acids involved in the interaction with poliovirus, we constructed a number of cDNAs encoding mutant hPVRs whose domain 1 was partially derived from mouse PVR (mPVR) homolog, which does not serve as a binding site for poliovirus. Poliovirus binding and infection assays were performed on mouse L cells that express these chimera cDNAs. Anti-hPVR monoclonal antibodies were employed to confirm the presence of mutant PVRs on the surface of mouse cells and to know conformational alteration of these PVRs. A significant decrease in efficiency of both poliovirus binding and infection to the cells was observed when one or a few amino acids of hPVR at Gly73, Ser74, Gln82, Leu99-Glu102, or Gln130-Ser132 were substituted by the corresponding amino acids of mPVR. Similar results were obtained when a 2-amino acid insertion of mPVR, which was missing in hPVR, was introduced at the corresponding site (between Arg98 and Leu99) of hPVR. These amino acids were highly conserved in functional PVRs of primates but not in unfunctional PVRs of rodents. These results indicate that the amino acids identified may have important roles in interaction of PVR with poliovirus that leads to the establishment of the virus infection. In the three-dimensional model of the domain 1 of hPVR, these amino acids are located on one side of the molecule. This suggests that the interaction with poliovirus occurs on this side of the domain 1.

Tissue tropism and species specificity of poliovirus infection

Paralytic poliomyelitis is caused by the destruction of neurons in the central nervous system during the lytic replication of poliovirus. The human gene for the poliovirus receptor has been cloned recently, and transgenic mice generated that are susceptible to this virus. This has allowed the critical amino acids that determine the specificity of poliovirus to be identified.

Repopulation of tumour cells following irradiation with X-rays or low energy neutrons

The repopulation of C3H mouse mammary carcinoma cells following X-ray or fast neutron irradiation was investigated in vivo using TCD50 as an endpoint. Tumours in the C3H mouse leg were irradiated in air with an X-ray dose of 9.6, 28.8 or 48.0 Gy, or a neutron dose of 2.6 or 5.2 Gy, and, various times thereafter, graded X-ray doses were given under hypoxic conditions to determine TCD50. Substantial recovery from sublethal and potentially lethal radiation damages was observed within 48 h following X-ray irradiation, and less recovery was found after neutrons. The effective number of tumourigenic cells was calculated at the time of the second irradiation using the TCD50 equation based on the multitarget model. The effective cell doubling time following X-rays depended on radiation dose. Repopulation appeared to be faster after small and intermediate X-ray doses (9.6 and 28.8 Gy) than after the largest dose, but substantial division delay was observed after the largest X-ray dose. A significant finding was that the tumour cells treated with a neutron dose, either 2.6 or 5.2 Gy, appeared to repopulate slightly more rapidly than those irradiated with X-rays, and the doubling times following two different neutron doses were not significantly different. These results suggest the use of a short overall treatment time for the high LET radiotherapy, and that caution must be exercised if the high LET radiation is given before photon doses.

Transgenic mice carrying the human poliovirus receptor: new animal models for study of poliovirus neurovirulence

Recombinant viruses between the virulent Mahoney and attenuated Sabin 1 strains of poliovirus type 1 were subjected to neurovirulence tests using a transgenic (Tg) mouse line, ICR-PVRTg1, that carried the human poliovirus receptor gene. The Tg mice were inoculated intracerebrally with these recombinant viruses and observed for clinical signs, histopathological lesions, and viral antigens as parameters of neurovirulence of the viruses. These parameters observed in the Tg mice were different for different inoculated viruses. Dose-dependent incidences of paralysis and of death were observed in the Tg mice inoculated with any viruses used. This indicates that values of 50% lethal dose are useful to score a wide range of neurovirulence of poliovirus. The neurovirulence of individual viruses estimated by the Tg mouse model had a strong correlation with those estimated by monkey model. Consequently, the mouse tests identified the neurovirulence determinants on the genome of poliovirus that had been identified by monkey tests. In addition, the mouse tests revealed new neurovirulence determinants, that is, different nucleotides between the two strains at positions 189 and 21 and/or 935 in the 5'-proximal 1,122 nucleotides. The Tg mice used in this study may be suitable for replacing monkeys for investigating poliovirus neurovirulence.

The response of quiescent cell populations in murine solid tumors to irradiation with fast neutrons

5-bromo-2'-deoxyuridine (BUdR) was injected into SCC VII tumor-bearing mice intraperitoneally to label all proliferating tumor cells. The mice were irradiated with fast neutrons or x-rays. Immediately, or 24 h after irradiation, the tumors were excised, minced and trypsinized. The tumor cell suspensions were incubated with cytochalasin-B (a cytokinesis blocker). The micronucleus frequency was determined using immunofluorescence staining to BUdR. The cells that were not labeled with BUdR could be regarded as the quiescent cells. The micronucleus frequency in total tumor cells was determined from the irradiated tumors that were not pretreated with BUdR. The difference in radiosensitivity between total and quiescent cells was markedly reduced with fast neutrons, especially at higher doses of radiation. Potentially lethal damage repair by total and quiescent cells was inhibited more strongly with neutrons than with x-rays. When using fast neutrons, the radiosensitivity of solid tumors depends on their heterogeneity less critically than for x-rays.

[Mandibular reconstruction using a vascularized osteocutaneous scapular flap]

Composite tissue defect of the mandible following the surgical resection of head and neck neoplasma or osteoradionecrosis causes functional and cosmetic disorders. Mandibular reconstruction is, therefore, necessary to obtain satisfactory results. The introduction of microvascular surgery has made it possible to transfer various types of vascularized bone grafts and this technique is considered one of the most reliable procedures for mandibular reconstruction. Recently it has been reported that an osteocutaneous scapular flap is useful for mandibular reconstruction. We have performed, over the last 2.5 years, 13 mandibular reconstructions using a vascularized osteocutaneous scapular free flap, and successful results have been achieved. The features of this flap are as follows: 1) it provides a consistent blood supply to the bone and the skin and has a constant vascular pedicle; 2) since the skin island and bone flap have separate pedicles, three-dimensional reconstructions are facilitated; 3) if needed, two skin flaps can be elevated; 4) the skin island is not so bulky; 5) the lateral border of the scapula provides highly vascularized bone of thick cortical density and osteotomies are safely performed; 6) using an angular branch based on thracodorsal artery, a bi-pedicled scapula bone can be raised and two completely vascularized bone segments can be transferred with a single pedicle. Thus, a vascularized osteocutaneous scapular flap has proven very useful for complex mandibular reconstructions.

Microamperometric estimation of photosynthesis inhibition in a single algal protoplast

The single-cell level inhibition of photosynthesis by some chemicals was investigated from the light-irradiation induced response of intracellular oxygen reduction current at an ultramicroelectrode inserted into a single algal protoplast. The addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), an electron-transport inhibitor, decreased a current peak appeared immediately after the light irradiation. The pI50 value (the negative decadic logarithm of the concentration needed for 50% inhibition) was determined from the change in response patterns and found to be 6.9 for DCMU. 2,4-Dichlorophenoxyacetic acid (2,4-D), an auxin herbicide, showed no effect on photosynthesis in the effective concentration range. 2,4-Dinitrophenol (DNP), a proton carrier, accelerated the oxygen production upon light irradiation.

[Expression of epidermal growth factor receptor in squamous cell carcinoma of the head and neck]

Localization of epidermal growth factor receptor (EGFR) was investigated immunohistologically in 68 untreated patients with squamous cell carcinoma of the head and neck regions. These patients consisted of 16 with cancer of the lips and mouth, seven with mesopharyngeal cancer, six with epipharyngeal cancer, 15 with hypopharyngeal cancer, 10 with laryngeal cancer, 12 with maxillary cancer and two with other tumors (cancer of the auricle and cancer of the eyelid in one patient each). The patients consisted of 57 men and 11 women, with a mean age of 60 years. In cases with a normal oral mucosa, marked expression of EGFR was observed in the epithelial cell membrane, while expression decreased toward the luminal surface. Cancer cells also showed positive staining of EGFR in all patients, but the intensity of staining was inconsistent among them. Among the 32 patients in whom the staining intensity of EGFR was equal to or weaker than that in basal cells of the normal oral mucosa, 12 patients had lymph node metastasis. Twenty-eight of the 36 patients in whom the staining was stronger than that in the normal cells had lymph node metastasis, suggesting that overexpression of EGFR in carcinoma cells is a risk factor for lymph node metastasis of head and neck cancers (P < 0.005). On the other hand, there were no obvious relationships between either the size or the degree of keratinization of the primary lesion and EGFR expression.

[Skull base surgery using the degloving technique--an approach without facial scarring]

Skull base surgery has been performed in 16 cases for en bloc resection of the nasal cavity and paranasal sinus carcinoma invading the anterior and middle skull base in our department. The surgical approach to skull base surgery is mainly a combined craniofacial approach, which includes craniotomy via a coronal incision intracranially and a transfacial or transoral approach extracranially. The direct transfacial approaches, such as lateral rhinotomy, Weber-Furguson incision, and midfacial split, resultin facial scarring. The midface degloving procedure was reported by Casson in 1974. This method can expose the midfacial skeleton by lifting the soft tissue from the face through an intraoral approach without external scarring. The authors have modified Casson's facial degloving technique and applied it to skull base surgery. The entire cranium and facial skeleton can be extensively degloved by using coronal, gingival and conjunctival incisions. Then, en bloc resection of the craniofacial compound segment can be accomplished through this degloving approach without external scarring of the face in anterior and middle skull base surgery. The authors have performed this procedure in 2 cases, and proved it to be an extremely valuable technique, displaying excellent cosmetic and functional results with minimal complications.

Microring-ring electrode for manipulation of a single cell

Dielectrophoretic manipulation of a single myeloma cell was carried out using microring-ring electrodes (tip radius, 3-5 microns). When a.c. voltages were applied, the cell nearby the electrode tip was forced to move and trapped at the tip due to dielectrophoretic force induced by locally intense electric field.

[Intravascular ultrasound imaging on the endarterectomized coronary arteries in two patients]

Intravascular ultrasound imaging on the endarterectomized coronary arteries in two patients are reported with a review of the literature. Case 1, a 62-year-old male and case 2, a 64-year-old male underwent endarterectomy of the right coronary artery (#3--#4PD, 4AV) combined with coronary arterial bypass grafting. Coronary arteriography (CAG) and intravascular ultrasound imaging (IVUS) were performed one month after operation. CAG revealed bypass grafts and endarterectomized coronary arteries to be patent together, and IVUS revealed endarterectomized coronary arteries had two layers, outer layer to be hyperechoic and inner layer to be heterogenously echoic in both cases. The histological examination of specimens suggests this heterogenously echoic area represents media, thrombus and irregularly proliferated intima. Therefore, anticoagulant therapy after endarterectomy should be strictly performed.

Temperature-sensitive mouse cell factors for strand-specific initiation of poliovirus RNA synthesis

Two cell lines, TgSVA and TgSVB, were established from the kidneys of transgenic mice carrying the human gene encoding poliovirus receptor. The cells were highly susceptible to poliovirus infection, and a large amount of infectious particles was produced in the infected cells at 37 degrees C. However, the virus yield was greatly reduced at 40 degrees C. This phenomenon was common to all mouse cells tested. To identify the temperature-sensitive step(s) of the virus infection cycle, different steps of the infection cycle were examined for temperature sensitivity. The results strongly suggested that the growth restriction observed at 40 degrees C was due to reduced efficiency of the initiation process of virus-specific RNA synthesis. Furthermore, this restriction appeared to occur only on the synthesis of positive-strand RNA. Virus-specific RNA synthesis in crude replication complexes was not affected by the nonpermissive temperature of 40 degrees C. In vitro uridylylation of VPg seemed to be temperature sensitive only after prolonged incubation at 40 degrees C. These results indicate that a specific host factor(s) is involved in the efficient initiation process of positive-strand RNA synthesis of poliovirus and that the host factor(s) is temperature sensitive in TgSVA and TgSVB cells.