Brain-derived neurotrophic factor regulates glucose metabolism by modulating energy balance in diabetic mice.

We previously reported that brain-derived neurotrophic factor (BDNF) regulates both food intake and blood glucose metabolism in rodent obese diabetic models such as C57BL/KsJ-lepr(db)/lepr(db) (db/db) mice. To elucidate the effect of BDNF on glucose metabolism, we designed a novel pellet pair-feeding apparatus to eliminate the effect of appetite alteration on glucose metabolism. The apparatus was used to synchronize food intake precisely between BDNF-treated and vehicle-treated db/db mice. It was shown using this pellet pair-feeding apparatus that BDNF administered daily (20 mg x kg(-1) x day(-1)) to db/db mice significantly lowered blood glucose compared with pellet pair-fed db/db mice. To evaluate the effect of BDNF on insulin action, we used streptozotocin-induced type 1 diabetic mice. In this case, BDNF did not lower blood glucose concentration but rather enhanced the hypoglycemic action of insulin. In hyperglycemic db/db mice, pancreatic insulin content was reduced and glucagon content was increased compared with normoglycemic db/m mice. BDNF administered to db/db mice significantly restored both pancreatic insulin and glucagon content. Histological observations of aldehyde-fuchsin staining and immunostaining with anti-insulin indicated that insulin-positive pancreatic beta-cells were extensively regranulated by BDNF administration. We also studied the effect of BDNF on KK mice, normoglycemic animals with impaired glucose tolerance. In these mice, BDNF administration improved insulin resistance in the oral glucose tolerance test. To elucidate how blood glucose was metabolized in BDNF-treated animals, we investigated the effect of BDNF on the energy metabolism of db/db mice. Body temperature and oxygen consumption of the pellet pair-fed vehicle-treated mice were remarkably lower than the ad libitum-fed vehicle-treated mice. Daily BDNF administration for 3 weeks completely ameliorated both of the reductions. Finally, to clarify its action mechanism, the effect of intracerebroventricular administration of BDNF on db/db mice was examined. Here, a small dose of BDNF was found to be effective in lowering blood glucose concentration. This indicates that BDNF regulates glucose metabolism by acting directly on the brain.

Seasonal and interannual variations in feeding station behavior of cattle: effects of sward and meteorological conditions.

A feeding station is the area of forage a grazing animal can reach without moving its forefeet. Grazing behavior can be divided into residence within feeding stations (with bites as benefits) and movement between feeding stations (with steps as costs). However, relatively little information has been reported on how grazing animals modify their feeding station behavior seasonally and interannually in response to varying environmental conditions. The feeding station behavior of beef cows (Japanese Black) stocked on a tropical grass pasture (bahiagrass dominant) was monitored for 4 years (2010 to 2013) in order to investigate the association of feeding station behavior with meteorological and sward conditions across the seasons and years. Mean air temperature during stocking often exceeded 30°C during summer months. A severe summer drought in 2013 decreased herbage mass and sward height of the pasture and increased nitrogen concentration of herbage from summer to autumn. A markedly high feeding station number per unit foraging time, low bite numbers per feeding station and a low bite rate were observed in summer 2013 compared with the other seasons and years. Bite number per feeding station was explained by a multiple regression equation, where sward height and dry matter digestibility of herbage had a positive effect, whereas air temperature during stocking had a negative effect (R 2=0.658, P<0.01). Feeding station number per minute was negatively correlated with bite number per feeding station (r=-0.838, P<0.001). It was interpreted that cows modified bite number per feeding station in response to the sward and meteorological conditions, and this largely determined the number of feeding stations the animals visited per minute. The results indicate potential value of bite number per feeding station as an indicator of daily intake in grazing animals, and an opportunity for livestock and pasture managers to control feeding station behavior of animals through managements (e.g. fertilizer application, manipulation of stocking intensity and stocking time within the day).

Functional sites of cytochrome c and other electron carrier proteins: semi-empirical molecular orbital program PM3 applied to the conformational analysis of Cys-X1-X2-Cys peptides.

The semi-empirical molecular orbital program, MOPAC version 6.0, PM3 was applied to estimate the distance between two sulfur atoms of two Cys side chains in optimized conformers of Cys-X1-X2-Cys sequences, as well as the total energy of that conformer relative to the most stable one. Some Cys-X1-X2-Cys tetrapeptides found in cytochrome c were optimized to conformers whose sulfur-sulfur distances were just suitable for binding to heme, whereas some tetrapeptides not found in cytochrome c were unable to be optimized to heme-binding conformers. Similarly, Cys-X1-X2-Cys tetrapeptides found in [4Fe-4S]ferredoxin were optimized to [4Fe-4S]-binding conformers, etc. The tetrapeptides found in the redox site of thioredoxin were optimized to conformers in which the two sulfur atoms were in van der Waals contact, so that a disulfide bond may be formed during the function. The conclusion has been drawn that the combination of X1 and X2 in a Cys-X1-X2-Cys sequence may be determining for that sequence to be a functional redox site in an electron carrier protein.

An explanation for the "two fiber axes" problem in human enamel by x-ray diffraction.

Since Thewlis found the "two fiber axes" patterns on x-ray diffractograms of human enamel in 1934, many investigators have studied this problem. However, a definite answer has not yet been obtained. The present detailed x-ray diffraction study showed that the "two fiber axes" patterns in human enamel were caused by reflections from the two zones of the Hunter-Schreger bands being recorded simultaneously on x-ray film, because we used an x-ray beam far larger in size than the width of the Hunter-Schreger bands.

Prism arrangement in human cusp enamel deduced by X-ray diffraction.

Analysis of the many X-ray diffractograms obtained from the regions along the bands of Hunter-Schreger, and a series of X-ray patterns taken by tilting the specimen with respect to the incident X-ray beam over a wide range of tilt angles, showed that the fibre axis of the crystal aggregates in each zone of the bands not only deviated in opposite directions but also tilted at an angle of about 50 degrees with respect to the central axis of tooth enamel. Comparison with previous studies enabled a fundamental and simplified three-dimensional model of human cusp enamel to be constructed, consisting of two groups of spirally-arranged structure which would probably be elastic enough to fulfil its unique functions in occlusion and mastication.

Tsutsugamushi disease in Kanagawa Prefecture, Japan: clinical report of two cases and survey of other incidences in 1998.

Tsutsugamushi disease is characterized by the early appearance of a black crust at the bitten area and the subsequent development of macular or macropapular rush on the whole body with high fever. While treatment with tetracycline derivatives and chloramphenicols is effective, delayed diagnosis or inappropriate treatment will lead to fatality. In this report, we describe two typical cases of tsutsugamushi disease and discuss other incidences in Kanagawa Prefecture, Japan, in 1998. One of the present two patients was diagnosed to be a case of the new type by Kawasaki strain of Rickettsia tsutsugamushi, while responsible strain was not identified for the other case. Since the disease is spreading widely even to suburban areas, we emphasize the need to consider the possible diagnosis of tsutsugamushi disease in patients with generalized eruption and high fever.

[Interferon-alpha].

Among interferon (IFN)-alpha, beta, gamma, there are no differences in its clinical effects and toxicities. As to IFN-alpha, there are leukocyte IFN, lymphoblastoid IFN, recombinant IFN-alpha 2a, 2b, and 2c. Now we have largely completed the process of surveying for anticancer effects over the broad range of malignancies. However, the adequate method of administration, route, dose, and interval are not yet fully established. Dose response remains unanswered question with some contradictory results in in vitro and clinical reports. The actual mechanism responsible for its anticancer activity is still not known. The question of what variables to monitor in assessing adequate dosages of IFN remains unsolved. Several trials have examined the possibility of combining IFN with other treatment modalities including anticancer agents, BRMs, radiation, etc. It should be acknowledged that we remain at a very early stage in our understanding of IFN. In future, IFN may play an even larger role when used in an adjuvant setting or as part of multimodality cancer treatment.

[Phase II clinical trial of MCNU].

MCNU is a new derivative of nitrosourea and experimental studies have shown equal or superior activity to known nitrosourea compounds. Twenty one cases were entered into our clinical studies with a phase II study. Nineteen cases have had a several courses of prior chemotherapy. Four out of 21 cases achieved a partial response (each one of lymphoepithelioma, parotid gland cancer, recurrent uterine cancer and recurrent breast cancer). The major toxicity encountered during treatment was myelosuppression. Full recovery of myelosuppression was delayed and was seen six to eight weeks after each injections. These initial results justify further clinical investigations with MCNU.

[Pharmacokinetics of human interferons].

Interferon in the blood was rapidly cleared from the circulation after intravenous injection. Intramuscular injection of alpha-interferon caused low but stable interferon levels in the blood. However, in the case of beta-interferon, interferon was never detected consistently in the blood after intramuscular or subcutaneous administration. Intraarterial administration of beta-interferon also caused low but stable interferon levels in the blood. Our studies suggest that beta-interferon should be given intravenously to see clinical beneficial. No difference in pharmacokinetics was seen between natural interferon and recombinant interferon. No difference was also noted between partially purified interferon and highly purified interferon.

[Pancreatic oncofetal antigen (POA)].

Recently, there has been an increasing interest in the diagnostic and prognostic usefulness of tumor-associated antigen of embryonic and fetal origin. Many approaches have been attempted to make an early diagnosis of the pancreatic cancer, where a specific screening blood test for the pancreatic cancer is required. By using antiserum to fetal pancreas, Banwo et al, discovered an oncofetal antigen that was present in human fetal pancreas, pancreatic tumor tissue, and sera from patients with the pancreatic cancer. Pancreatic oncofetal antigen (POA) was considered to be an oncofetal antigen for human pancreas, and its measurement seemed to be useful in the diagnosis of pancreatic cancer. But elevated levels of POA were also observed in the serum of some patients with cancer of the stomach, lung, colon, or liver as well as in the serum of some pregnant women and others with certain benign conditions. In summary, combined assay with various tumor markers was considered to be useful for the diagnosis of pancreatic cancer.

[Clinical experiences with pepleomycin].

From experimental observations, Peplomycin was expected to be more active against a variety of tumors and to be less toxic for the lung than the parent compound. An intermittent dose(10mg. twice a week) of peplomycin was tested in patients with malignant lymphoma or squamous cell carcinoma who had failed conventional treatment. There were two cases of CR and five cases of PR in twelve cases with malignant lymphoma, and two cases of PR in fourteen cases with squamous cell carcinoma. Out of 26 cases treated with peplomycin, fever was seen in ten cases(38.5%) and pulmonary complication was seen in five cases (19.2%). These data obtained from peplomycin treatment were compared with the results obtained from our previous experiences with bleomycin. Response rate, spectrum and frequency of side reactions of peplomycin treatment were substantially identical with those of bleomycin treatment. However, remission duration and life span were much longer in peplomycin treatment. In this respect, peplomycin seems to be superior than bleomycin to a certain extent.

[Interferon production in vitro].

Interferon production in vitro was induced by poly I: C and PHA in leukocytes obtained from patients with cancer, benign diseases and control subjects. The interferon response per lymphocyte was relatively constant in all groups. However, interferon production was slightly inhibited in patients receiving cancer chemotherapy. The peak response of interferon occurred at 48 hours after the initiation of the combined culture in each specimen. From our observations, it was suggested that interferon production in vitro seems to be useful marker for evaluation of effect of chemotherapy and or immunotherapy, and, furthermore, in the treatment of cancer patients with interferon inducers, there seems to be optimum BRM dose and optimum timing of administration.

[Host factors in cancer chemotherapy].

Cancer grows in interaction with the host, that is, a host-tumor relationship exists. Investigations of host factors in patients receiving cancer chemotherapy are important, as they reveal the conditions in which a tumor response can develop. Furthermore, reliable host factors, if present, will be useful for quantitative evaluation of the effects of treatment. We have investigated the following three categories of host factors in relation to the effects of cancer chemotherapy and/or immunotherapy. CBC, and blood chemistries (44 parameters). Tumor markers; sialic acid, RNase, lysozyme, ferritin, IAP (immunosuppressive acidic protein), elastase I, AFP, CEA, POA, CA 19-9, CA 125, etc. Immunological parameters; lymphocyte, active T cell, T cell, B cell, IgG Fc receptor-positive T cell, lymphocyte blastogenesis stimulated by PHA, or concanavalin-A, ADCC activity, interferon production in vitro induced by poly I: C, or PHA, PPD skin test, immune complex, immunoglobulin G, A, and M, OKT series 3, 4, 8, 11, 4/8 ratio, antihuman HLA-DR, Leu 11, NK cell activity, etc. From our clinical observations, there were no significant differences in the pretreatment levels of these parameters between responders and non-responders. In responders, there was a tendency for the host factors to show greater degrees of improvement following treatment than in non-responders, but none proved to be reasonably reliable parameters for evaluating therapeutic effects. On the other hand, from our clinical observations on the advanced gastric cancer cases, life span showed a close correlation with tumor regression induced by cancer chemotherapy. Because of these facts, it is only natural that the clinical effects of chemotherapy are currently determined by definite tumor regression.

[Effective treatment of AFP-producing lung cancer with UFT].

The main form of chemotherapy for non small cell lung cancer is a multiple combination therapy centered on cisplatin (CDDP). We herein report a case in which a favorable course was obtained for a patient with extremely rare AFP-producing lung cancer by single oral administrations of UFT, following extirpation of brain metastasis. The patient was an 80-year-old male whose main complaints were headache and aphasia. Following close examination, a diagnosis was made of moderately differentiated adenocarcinoma with the primary lesion in S6 of the right lung. A metastatic lesion was found in the left occipital lobe. Blood AFP was an abnormally high 17,000 ng/ml. No tumorous lesions were found in the liver. The brain metastasis were extirpated to alleviate cranial nerve symptoms, and the tissue was found to be the same as that of the primary lesion. AFP staining of the tumor tissue revealed positive cells. Because there was proliferation in the primary tumor following surgery, administration of UFT (300 mg/day Tegafur) was begun. Four weeks later the tumor had begun to shrink, and at 15 weeks was judged to be a partial response. A reduction in AFP was also seen. The patient showed absolutely no side effects from UFT, thus enabling outpatient treatment. Good results were obtained both in reducing the tumor and in maintaining the patient's quality of life.

X-ray crystallographic studies as to the calcification in the Hunter-Schreger bands of human enamel.

By analyzing integrated intensities of X-ray diffraction patterns and X-ray diffractograms obtained from the two zones of the Hunter-Schreger bands, it was deduced that the ratio of the sums of the integrated intensities and the degree of preferred orientation of the crystal aggregates in both zones of the bands were almost the same in value, but the fiber axes of the two zones were oriented in different directions. From these experimental observations and a consideration of the effect of the orientation of the enamel prisms relative to the incident X-ray beam, it is concluded that the two zones of the bands were calcified evenly and the light and dark zones on the microradiographs were caused by the difference in the orientation of enamel prisms.