Enzymatic semisynthesis of [Leu B30] insulin

Experimental conditions for the preparation of [Leu^B30] insulin by coupling of des-Ala^B30 insulin with Leu-OBu^t were determined using Achromobacter protease I and trypsin as catalysts. Successful coupling required a large excess of the amine component (0.8 M), a high concentration of organic cosolvent (35–50%) and neutral pH of the reaction mixture. The coupling yield of Achromobacter protease I after 24 h at 37°C was almost the same or a little higher than that at 25°C. With trypsin, the coupling yield at 37°C after 24 h was considerably lower than at 25°C. This was partly ascribed to the difference in concentration of organic cosolvent at 37°C and 25°C; 35% and 50%, respectively, or possibly of enzyme stability at these temperatures. The maximum product yield was about 90% with both enzymes under optimal conditions. A preparative scale experiment was performed with Achromobacter protease I; the yield of [Leu^B30] insulin was 51% using porcine insulin as the starting material. This semisynthetic insulin was identified by HPLC and amino acid analysis. No difference was observed in CD spectra between [Leu^B30] insulin and human insulin.     

Hemoglobin FHouston: A Fetal Variant

A fetal hemoglobin variant, designated hemoglobin F_Houston, was found inthe cord blood sample of a healthy, term Negro infant. The variant, comprising about 15 per cent of the total cord blood hemoglobin, diminished concomitantly with hemoglobin F, and it was barely detectable in the blood whenthe infant was 4 months old. The hemolysates of the parents and two siblingsresolved into the usual adult pattern, but a trace amount of a fraction similarto hemoglobin F_Houston was present in the father’s hemolysates and not in themother’s.

The ultraviolet absorption spectrum indicates that hemoglobin F_HOUSTON contains polypeptide chains, and immunologic studies reveal the presence ofboth and chains. In hybridization tests the alteration appears in the chain.

Peptide chromatograms of hemoglobin F_Houston indicated the presence of and chains, but failed to reveal an abnormality. Amino acid analyses suggestthat there may be a substitution of an alanyl for a glutamyl residue.

Submitted on August 3, 1965 Accepted on October 12, 1965     

Ovarian mixed germ cell tumor composed of dysgerminoma, endodermal sinus tumor, choriocarcinoma and mature teratoma in a 44-year-old woman: Case report and literature review

A case of ovarian mixed germ cell tumor In a 44-year-old woman was examined. The tumor was well circumscribed, measured 15 times 11 times 10cm and appeared solid and partly cystic on the cut surface. Light microscopic examinations revealed that the tumor was composed of four different neoplastic germ cell elements, Intermingled with each other. They are: (i) choriocarcinoma, immunohistochemically positive for human placental lactogen (hPL) and human chorionic gonadotropin (hCG); (ii) dysgerminoma, positive for placental alkaline phosphatase; (iii) endodermal sinus tumor positive for α-fetoproteln (AFP); and (lv) mature teratoma. Among these histological types, dysgermlnoma occupied more than 50% of the neoplasm. The patient was diagnosed as a stage la ovarian mixed germ cell tumor and was subsequently treated with chemotherapy. A second-look laparotomy after completion of chemotherapy revealed no residual tumors in the abdomen and the patient Is alive and well 15 months after operation. This Is the fourth reported case of ovarian mixed germ cell tumor arising In patients over 40 years old.     

EXCRETION OF BIKUNIN AND ITS FRAGMENTS IN THE URINE OF PATIENTS WITH RENAL STONES

PURPOSE: Bikunin is a Kunitz-type protease inhibitor found in serum and urine. It has been implicated in urinary stone formation. This study was designed to investigate the role of urinary bikunin in stone formation. MATERIALS AND METHODS: Urinary concentrations of bikunin were measured in 18 male formers of urinary stones 28 to 74 years old and in 77 healthy controls, including 39 males and 38 females, without urological abnormality. A sensitive competitive solid phase enzyme immunoassay was established for urinary bikunin. Bikunin was also qualitatively assessed by Western blot analysis. RESULTS: The mean urinary bikunin-to-creatinine ratio plus or minus standard deviation in stone formers was significantly elevated compared with that in healthy male and female controls (52.9 +/- 46.0 microg./mg. creatinine versus 28.0 +/- 30.4 and 26.5 +/- 21.7, p = 0.005 and 0.006, respectively). By Western blot analysis all urine samples contained authentic 40 kDa. bikunin species. However, a significantly higher proportion of patients was found to have aberrant 25 kDa. bikunin species compared with controls (10 of 18 or 55.6% versus 15 of 77 or 19.5%, p = 0.002). Experiments on de-glycosylation with chondroitinase ABC, amino acid sequencing of the aberrant bikunin species and calcium oxalate crystal growth inhibition assay demonstrated that the 25 kDa. bikunin fragment was identical to de-glycosylated bikunin and less inhibitory on calcium oxalate crystal growth. CONCLUSIONS: If urinary bikunin is important in the pathogenesis of urolithiasis, its effect is probably attributable to the concentration and degree of glycosylation.     

Usefulness of ultrasensitive prostate-specific antigen assay for early detection of biochemical failure after radical prostatectomy

BACKGROUND: In order to assess whether the prostate-specific antigen (PSA) nadir obtained with an ultrasensitive PSA assay can be used as a prognostic indicator for patients undergoing radical prostatectomy, we investigated it retrospectively. METHODS: Between October 1997 and July 2003, 46 patients underwent radical prostatectomy for prostate cancer at our institution. None of them received preoperative treatment. Levels of PSA were measured with an ultrasensitive PSA assay every 1-3 months after prostatectomy. Biochemical recurrence was defined as a PSA level of 0.2 ng/mL or higher. RESULTS: There was a significant difference in PSA nadir between the biochemical recurrence group and the no recurrence group (P < 0.001). The receiver operating characteristics (ROC) curve gave an optimal cut-off value for PSA nadir of 0.01 ng/mL, demonstrating a significant difference in biochemical recurrence after radical prostatectomy. No patient with a PSA nadir level <0.01 ng/mL showed biochemical failure, while 15 out of 22 patients with PSA nadir levels >or=0.01 ng/mL showed biochemical failure. CONCLUSION: The PSA nadir level obtained using an ultrasensitive PSA assay is an excellent predictor of biochemical recurrence after radical prostatectomy. Early detection of recurrence offers the possibility of early salvage therapy.     

Comparison of two in vivo models for prostate cancer: Orthotopic and intratesticular inoculation of LNCaP or PC-3 cells

BACKGROUND: The critical events in the clinical course of prostate cancer are the occurrence of metastasis and the induction of the hormone-refractory status of the disease. In order to investigate the factors responsible for these events, we need appropriate in vivo models. MATERIALS AND METHODS: Orthotopic and intratesticular models were created by the injection of LNCaP cells or PC-3 cells into the prostate or testis of severe combined immunodeficient mice. RESULTS: LNCaP cells in the intratesticular model showed a higher incidence of tumor formation and lymph node metastasis when compared with those in the orthotopic model, while PC-3 cells were highly tumorigenic and metastastic in both models. A high concentration of androgens might play a role in tumor aggressiveness of LNCaP cells, given that enhanced mRNA expressions of integrin alphaV and vascular endothelial growth factor was induced by dehydrotestosterone administration in vitro. The high expression of metastasis-related genes, including the urokinase plasminogen activator system, metalloproteinases and vascular endothelial growth factor-C, might be attributed to the high metastatic potential in both models. Interestingly, testicular xenografts of LNCaP cells were able to survive on the subcutis back of castrated male mice as well female mice. CONCLUSIONS: Intratesticular models of prostate cancer appear to be suitable for studying the mechanisms of metastasis and for evaluating various treatment strategies.     

Influence of heart surgery on magnesium concentrations in pediatric patients

BACKGROUND: There have been only a few investigations into the effects of cardiopulmonary bypass (CPB) on the magnesium (Mg) concentrations in pediatric patients. The purpose of the present study was to compare the postoperative Mg concentrations and their recovery time to pre-surgical values in pediatric patients undergoing CPB for surgical repair of congenital heart disease. The incidence of dysrhythmia was also determined. METHODS: Twenty-seven pediatric patients undergoing open-heart surgery with CPB were enrolled in this study. Controls were 23 pediatric patients undergoing palliative surgery without CPB. Serum Mg (SMg) concentrations and ionized Mg (iMg) concentrations were measured at four sample points: 24 h before the surgery, immediately after the surgery, 24 h after the surgery and 48 h after the surgery. RESULTS: Serum Mg and iMg concentrations were significantly decreased after open-heart surgery. Immediately after the surgery, the mean SMg concentration was 64.1% and the mean iMg concentration was 68.8% of the pre-surgical values. The concentration of iMg showed quicker recovery than that of SMg, and returned to normal range 48 h after surgery. However, SMg and iMg concentrations after palliative surgery did not show significant differences from the pre-surgical values. The incidence of dysrhythmia was almost the same between the two groups; dysrhythmia was observed in two patients in the open-heart surgery group and in three patients in the palliative surgery group. CONCLUSIONS: Mg concentrations showed significant decrease after CPB; however, they showed quick recovery and did not increase the incidence of dysrhythmia in pediatric patients.     

Acute myeloblasts leukaemia without Philadelphia chromosome developing after interferon therapy for chronic myelocytic leukaemia with Philadelphia chromosome

Summary. We report a patient who developed Philadelphia chromosome negative acute myeloblastic leukaemia with trisomy 8 and trisomy 11 after receiving treatment with alkylating agents and interferon for chronic myelocytic leukaemia positive for Philadelphia chromosome. Leukaemic cells were positive for myeloperoxidase and expressed CD13, CD33 and DR; some expressed CD2, CD4 and CD34. The fluorescence in situ hybridization method revealed that bcr-abl fusion genes were absent from > 90% of the bone marrow cells. The major bcr rearrangement was not detected by Southern blot analysis. We conclude that the leukaemic cells negative for Philadelphia chromosome may have developed as a result of treatment with alkylating agents and interferon in the present case.     

A case of Kabuki make-up syndrome with EBV+ Burkitt's lymphoma

Kabuki make-up syndrome was first reported in 1981 and is characterized by peculiar facies with post natal growth deficiency and mental retardation. Since the first report, approximately 100 cases have been reported, but there have been no reports of tumor development. A case is reported of a patient with Kabuki make-up syndrome who developed malignant lymphoma in his abdomen at the age of 3 years. The tumor was histologically diagnosed as Burkitt's lymphoma and Epstein-Barr virus was detected by in situ hybridization.     

A COMPARATIVE STUDY OF ETHANOL ABSORPTION IN THE CANINE JEJUNUM AFTER PRETREATMENT WITH CYANAMIDE OR PYRAZOLE

This report describes the retardation of ethanol absorptionfrom the intestinal tract and reduction of portal blood flowby high acetaldehyde concentrations in dogs using a jejunalsegment with the vascular supply intact. The cyanamide-pretreatmentgroup (CY), in which an extremely high acetaldehyde concentrationdeveloped, in comparison with the control and pyrazole-pretreated(PY) groups, showed a gradual increase of portal blood ethanol,a 25% reduction in the amount of absorbed ethanol, and an 85%smaller absorption rate constant value (K_a). These facts indicatethat the presence of a high acetaldehyde concentration in theblood results in a reduction of ethanol absorption and retardationof ethanol reaching the systemic circulation. The rapid reductionof portal blood flow and the lower ethanol level in the portalvein observed in the CY group, in comparison with the othertwo groups, also indicate that the reduction of ethanol permeabilitythrough the absorption site to the blood is an important retardingfactor induced by acetaldehyde.