Conformational behavior of C alpha,alpha-diphenyl glycine: extended conformation in tripeptides containing consecutive D phi G residues.

Recent studies on the conformational preferences of the Dphig (C(alpha,alpha)-diphenylglycine) residue showed that this C(alpha,alpha)-disubstituted glycine has a structural versatility. In fact, depending on the nature of the following or preceding residue, Dphig can assume either folded or extended conformations. We have carried out the analysis of the conformational preferences of the Dphig residue in tripeptides containing consecutive Dphig residues. The crystal structures of Z-Dphig-Dphig -Dphig-OMe (a; Z = benzyloxycarbonyl; OMe = methyl ester), Z-Aib-Dphig-Dphig-OMe (b; Aib = alpha-aminoisobutyric acid), and Z-Ac(3)c-Dphig-Dphig-OMe (c; Ac(3)c = alpha-amino-cyclopropan carboxylic acid), are here reported. The Dphig residues adopt the fully extended conformation in the three tripeptides examined. Together with our previous findings on Dphig containing peptides, the structures of the peptides here examined, indicate that the presence of adjacent Dphig residue in the sequence further stabilizes the extended conformation.

Conformational behaviour of C(alpha,alpha)-diphenylglycine: folded vs. extended structures in DphiG-containing tripeptides.

The crystal structures of three fully protected tripeptides containing the Dphi g residue (C[alpha,alpha]-diphenylglycine) in the central position are reported, namely Z-Gly-Dphi g-Gly-OMe (a), Z-Gly-Dphi g-Aib-OMe (b) and Z-Aib-Dphi g-Aib-OMe (c). The molecular conformations are quite unusual because the Dphi g residue adopts a folded conformation in the 3(10)-helical region when the following residue adopts a folded conformation of opposite handedness (peptides b and c). In contrast, the Dphi g residue adopts the more frequently observed fully extended conformation when the following residue adopts a semi-extended conformation (peptide a). These findings are in agreement with the theoretical calculations on Ac-Dphi g-Aib-NHCH3 and Ac-Aib-Dphi g-NHCH3 also reported in this work.

[A case of polyglandular autoimmune syndrome (PGA) type 1 complicated with slowly progressive IDDM].

A case of an 18-year-old female with polyglandular autoimmune syndrome (PGA) type 1 complicated by slowly progressive IDDM was described. She had epilepsy at the age of 5, and mucocutaneous candidiasis and hypoparathyroidism at 7 years. At the age of 18, the patient noticed thirst and body weight loss. On admission, she had uneven teeth and chronic mucocutaneous candidiasis. Plasma blood glucose was 312 mg/dl without ketosis, hemoglobin Alc 9.1%, serum calcium 3.5 mEq/l, serum phosphorus 6.0 mg/dl. A CT scan of her brain revealed calcification in the bilateral basal ganglia. Serum intact PTH was less than 10 pg/ml. Ellsworth-Howard's test showed hyperresponsiveness in the secretion of urinary phosphorus and cyclic-AMP. Other endocrinological studies showed no abnormality except for mild hyporesponsiveness in the secretion of urinary C-peptide (39.6 mu g/day). After admission, she was initially treated with diet alone with positive islet cell antibody (ICA). Three months later she was treated with low dose insulin, and ICA became negative. Then 5 months later it became positive again. Sixteen months later she had IDDM with positive ICA and without the secretion of urinary C-peptide. On the basis of these results, we diagnosed this case as PGA type 1 with the manifestations of hypoparathyroidism, chronic mucocutaneous candidiasis and slowly progressive IDDM. This is the second case report in Japan about PGA type 1. Furthermore, this case demonstrates for the first time in Japan that slowly progressive IDDM is complicated by PGA type 1. The patient had this HLA typing: A 24(9), BW52(5), BW60(40), CW3, DR2, DRW12, DQW7. More investigation is necessary to clarify the mechanism of PGA type 1.

Mixed conformation in C alpha, alpha-disubstituted tripeptides: x-ray crystal structures of Z-Aib-Dph-Gly-OMe and Bz-Dph-Dph-Gly-OMe.

We report here the synthesis and molecular structure in the solid state of fully protected tripeptides containing C alpha, alpha-diphenylglycine (Dph), namely Z-Aib-Dph-Gly-OMe (Aib: C alpha, alpha-dimethylglycine) and Bz-Dph-Dph-Gly-OMe. The molecular conformation around the Dph residue, containing two bulky substituents, is fully extended, while the Aib residue, containing two smaller groups on the C alpha atom, adopts the typical 3(10)/alpha-helical conformation. Gly residues, without substituents on the C alpha atom, show different conformational preferences. Each residue seems to behave, from a conformational point of view, independently from the presence of the other residues, and thus mixed local conformations (folded and extended) are present in the crystals. The nonconventional peptide synthesis, using the Ugi reaction, is also reported.

[Postoperative reconstruction of chest wall using polyglycolic acid mesh--a case report].

A 75-year-old male with infected chest wall tumor was treated with en-block resection of the tumor including the second and third ribs, part of the M. pectoralis major, pleura and pulmonary parenchyma. As the wound was infected, the defect of the chest wall was reconstructed leaving a muscle pedicle of the pectoralis major and polyglycolic acid mesh, 9.0 x 8.5 cm in area. The resected tumor was 9.0 x 8.0 x 4.0 cm in size, 170 gr in weight and histopathologically poorly or moderately differentiated adenocarcinoma. The primary lesion of the tumor was unknown in spite of investigations of the whole body. The postoperative course was uneventful, and the wound was completely healed within 3 weeks. This mesh material was therefore considered to be useful for reconstruction of the chest wall especially in the infected region.

[Effectiveness of fibrin glue in preventing postoperative pulmonary air leakage].

The authors investigated the effectiveness of fibrin glue in preventing pulmonary air leakage after lung surgery. We first examined 29 patients who underwent pulmonary resection without the use of fibrin glue. On the basis of preoperative spirometry data, these patients were divided into normal respiratory function and poor function groups (%VC < 80% and/or FEV1.0% < 70%), and the duration of postoperative pulmonary air leakage in each group was studied. The duration was 2.2 +/- 1.4 days (mean +/- S.D, n = 18) in the normal group and 5.2 +/- 4.3 days (mean +/- S.D, n = 11) in the poor respiratory function group. The latter values were significantly greater than the former (p < 0.05, unpaired t-test). Then we examined seven patients who underwent lung surgery with the use of fibrin glue. We found that in three patients with normal respiratory function, the air leakage disappeared within one day, and in four patients who had poor respiratory function, the air leakage disappeared in three days. In both respiratory function groups, the air leakage seemed to disappear more quickly with the use of fibrin glue. These results suggest that fibrin glue is effective in preventing pulmonary air leakage.

The superiority of UW solution for maintaining ATP concentrations during pulmonary preservation.

We evaluated three solutions used for preserving lungs, namely, University of Wisconsin (UW), Euro-Collins (E-C), and low potassium dextran (LPD), by measuring the high energy phosphates in the preserved lung tissue. The left lungs of Sprague-Dawley rats were excised and flushed with 5 ml of one of the solutions at 10 degrees C through the pulmonary artery, after which they were deflated and immersed in the solution at 10 degrees C for 24 h. The tissue adenosine triphosphate (ATP) concentration in mumol/g tissue wet weight after 24 h of storage was 2.55 +/- 0.48 (n = 7) in the UW lungs, 1.98 +/- 0.25 (n = 6) in the E-C lungs, and 1.53 +/- 0.32 (n = 4) in the LPD lungs, being significantly higher in the UW lungs than in either the E-C or LPD lungs (P < 0.05). The histopathological findings of the E-C lungs were more deteriorated, with marked interstitial edema, septal hypertrophy, and perivascular hyaline degeneration, than either the UW or LPD lungs. Thus, the findings of this study indicate the superiority of UW solution for lung preservation.

[Examination of post operative split lung function using quantitative xenon 133 (133Xe) inhalation scan].

133Xe inhalation scan and ordinary lung function testing were performed three times in 34 patients undergoing pulmonary resection: before surgery, and one and six months postoperatively. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1.0) were used as spirometric parameters. From the 133Xe inhalation scan, a split lung capacity (right to left, upper, middle and lower) and T1/2 (time required for half of the inhalation of 133Xe gas to be expired) were calculated by computer and used as indices of split lung capacity and ventilation, respectively. Results obtained from this study are as follows. 1) The predicted postoperative lung functions were calculated using preoperative spirometric respiratory function and 133Xe inhalation data according to the formula reported by Ali and associates. At sixth postoperative month, both predicted FVC (r = 0.895, p < 0.001) and FEV1.0 (r = 0.897, p < 0.001) correlated highly with those actually observed. These results appear to be very useful for preoperative evaluation of operative indications and the choice of surgical methods. 2) The ratios of observed to predicted lung capacity in the post operative state were examined by splitting the right and left lung and the means +/- S.D. (%) were as follows. One month after surgery, operated side; 80.5 +/- 9.7%, opposite side; 119.2 +/- 11.7%. Six months after surgery, operated side; 111.0 +/- 5.6%, opposite side; 96.7 +/- 16.4%. The post operative T1/2 values on the operated sides were about 2.4 times the preoperative values at one month after surgery but had recovered to the preoperative values by the six postoperative month.(ABSTRACT TRUNCATED AT 250 WORDS)

[Nd-YAG laser treatment of tracheo-bronchial stenotic lesions].

Fourteen patients were treated with a Nd-YAG laser. Treatment to relieve airway stenosis was administered on fifteen occasions, and on one occasion to treat an obstruction. In each case the flexible fiberoptic bronchoscope was used. In 4 emergency cases, three involving tracheal lesions and one involving a bronchial lesion, the airway was widened and the patients' condition was improved after laser ablation. In the palliative treatment of 12 lesions, the stenoses were severed and treated at an interval of time varying between one and three weeks. Complications occurred in 3 cases. There were 2 instances of massive haemorrhage and one of pneumothorax which occurred while treating the 5 stenoses situated at broncho-plastic anastomoses.

Detection and quantitative estimation of metalloporphyrins in vivo.

Spectrofluorometry, radioisotope (RI) labelling and high performance liquid chromatography (HPLC) can be used to estimate photosensitizer concentrations. The biodistribution of porphyrins and metalloporphyrins containing the bifunctional chelating agent diethylenetriamine pentaacetic acid (DTPA) was examined in tumour-bearing mice by nitrogen-pulsed laser spectrofluorometry (PLS) and RI labelling. The biodistribution of metalloporphyrin amino acid derivatives containing alkoxyl groups was also examined by PLS and HPLC analysis using an acetone powder extraction method. Spectrofluorometry is useful for estimating the biodistribution of porphyrins in tumour, lung, kidney and serum, but not in liver. However, spectrofluorometry cannot be used to evaluate the concentration of certain metalloporphyrins such as manganese complexes. The concentrations of porphyrins in liver measured by PLS and two other methods showed remarkable differences. RI labelling and HPLC analysis are obviously tedious methods. Therefore it seems practical to screen for a number of compounds using the spectrofluorometric method (PLS). Subsequently, the porphyrins which give good results with PLS should be measured using RI labelling and HPLC.

The tumour-localizing properties of porphyrin derivatives.

The tumour-localizing abilities of various kinds of porphyrin derivatives in tumour-bearing hamsters were assessed by nitrogen-pulsed laser spectrofluorometry (N2-PLS). On examination of porphine derivatives (from haemoglobin), it was found that the dimer and acetylated and amidated compounds had a high affinity for tumour tissue; the dimer and hydroxylated compound of phorbine derivatives (from chlorophyll) also showed a high affinity. Furthermore, of the metalloporphines (gallium, zinc and indium complexes), those which contained hydrophilic groups showed a high affinity for tumour tissue; of the metallophorbines (gallium, zinc and indium complexes), those which contained hydrophobic groups showed a high affinity. A correlation was found between the side-chain structure of the porphyrins and metalloporphyrins and their affinity for tumour tissue.

Treatment of experimental tumors with a combination of a pulsing magnetic field and an antitumor drug.

We investigated the effects of a combination treatment involving a pulsing magnetic field (PMF) and an antitumor drug, mitomycin C (MMC), on two experimental tumors (fibrosarcoma KMT-17 and hepatocellular carcinoma KDH-8) in WKA rats, paying attention to possible potentiation of the therapeutic effect of the antitumor drug. PMF was obtained using a system generating a pulsed current in a solenoid coil. On day 7 after tumor implantation into the right thighs of rats, the region of the tumor was exposed to PMF (frequency 200 Hz, mean magnetic flux density 40 gauss) for 1 h immediately after iv injection of MMC at a dose of 1 mg/kg. Survival rates at day 90 of KMT-17 implanted rats were 0% (0/10) in the non-treated group, 34% (4/12) in the MMC-treated group, 47% (6/13) in the PMF-treated group and 77% (10/13) in the MMC/PMF combination group. The increase of life span (ILS) of KDH-8-implanted rats in the combination therapy group was significantly prolonged (%ILS 17.6%) compared with that in the MMC-treated (%ILS 3.4%) and PMF-treated (%ILS 7.6%) groups. By using cultured cells of the above two lines of tumor, the therapeutic effects of MMC and PMF were also determined from the cell colony-forming efficiency in soft agar. The colony-forming efficiencies of both cell lines were significantly suppressed in the combination therapy group compared with those in the other single therapy groups. The present results indicate that PMF exhibited a potentiation of the antitumor effect of mitomycin C.

[An experimental attempt to potentiate therapeutic effects of combined use of pulsing magnetic fields and antitumor agents].

With a view to examining the possible clinical applicability of pulsing magnetic fields (PMF), we investigated the effects of weak, non-heat inducing, PMF on DNA synthesis and sensitivity of cancer cells to antitumor agents. Leukemic T-cells (Molt-4) and a pancreatic ductal adenocarcinoma (solid tumor) transplanted in a Syrian golden hamster were used for the in vitro experiment and in vivo experiment respectively. In order to evaluate the effects of PMF on the DNA synthesis of cancer cells and the incorporation of antitumor agent into cancer cells, cultured cells or solid tumor were exposed to PMF generated by a solenoid coil immediately after 3H-or 14C-thymidine and 3H-methotrexate administration respectively. Thymidine uptake was found to increase by exposure to PMF, as did also 3H-methotrexate uptake by leukemic T-cells. Following exposure to PMF immediately after administration of methotrexate or mitomycin C, antitumor activity in both cells was increased. From these results it appears that the incorporation of antitumor agents into the cells increases by eddy current stimulation induced by PMF, and that the cell cycle shifts from the non-proliferative to proliferative phase, resulting in increased antitumor activity.

[Effects of low-frequency pulsing magnetic field upon the respiratory metabolism and transmembrane ion fluxes of perfused rat livers].

UNLABELLED: Influence of magnetic fields on biological systems is not completely clear. Recently, experiments on the effects of weak not heat inducing electromagnetic fields concerning biological systems have been reported. We have investigated the effects of the weak low-frequency pulsing magnetic field (PMF) concerning the respiratory metabolism and transmembrane ion flux of perfused rat livers. MATERIALS AND METHODS: Livers from male Wistar rats were perfused via the portal vein with 95% O2-5% CO2 saturated Krebs-Henseleit Bicarbonate Buffer maintained at 32 degrees C. In 48 hrs fasted rats, lactate was administered in the perfusate as a substrate of gluconeogenesis in case of necessity. PMF generated by the solenoid coil was applied to the perfused livers. For monitoring of respiratory metabolism of the perfused livers, scanning spectrophotometry and NADH fluorometry were applied to the surface of the liver. The effluent was monitored for PO2 and analyzed for glucose, lactate and pyruvate. Ca2+, Mg2+, Na+, K+, Cl- ion from effluent were also analyzed. RESULTS: By being exposed to a low-frequency PMF, the O2 consumption increased in the perfused livers of the fed rats, but the degree was variable according to the metabolic state of the liver of each rat. In order to bring about a maximum reductive state, ethanol was given to the perfusate. Ethanol caused an increase in NADH and Lactate/Pyruvate ratio and O2 consumption and an inhibition of glucose production. By exposure to PMF the metabolism of perfused liver was shifted to the re-oxidative state. In lactate administered perfused liver of the 48 hrs fasted rats, PMF caused an increase in the livers sensitivity to glucagon. As regards the transmembrane ion fluxes, PMF acted antagonistically to the ethanol effect, especially when we used perfusate with low Ca2+ concentrations. So that an intimate association between PMF and intracellular Ca2+ regulating system was suggested.