Studies on a new antibiotic SF-2330. I. Taxonomy, isolation and characterization

A new antibiotic SF-2330 active against Gram-positive bacteria has been isolated from the culture broth of Streptomyces sp. SF-2330. The antibiotic was obtained as orange needle crystals and its molecular formula was C22H14O7. This is a new member of the pluramycin group antibiotics.     

Combination effect of recombinant human interleukin-1 alpha with antimicrobial agents.

Combination effects of recombinant human interleukin-1 alpha with ceftazidime, moxalactam, gentamicin, enoxacin, amphotericin B, miconazole, or an immunoglobulin preparation were evaluated in systemic infections with Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candida albicans in normal mice and systemic infection with P. aeruginosa in mice with leukopenia induced by preadministration of cyclophosphamide. Synergistic effects were generally observed at interleukin-1 alpha doses as low as 1 to 30 ng per mouse with most combinations. The results show the possibility that recombinant human interleukin-1 alpha could be of help for treating obstinate infections not successfully treated with antimicrobial agents alone.     

Poststatin, a new inhibitor of prolyl endopeptidase, produced by Streptomyces viridochromogenes MH534-30F3. I. Taxonomy, production, isolation, physico-chemical properties and biological activities

Poststatin, a new inhibitor of prolyl endopeptidase (PEP) was discovered in the fermentation broth of Streptomyces viridochromogenes MH534-30F3. It was purified by Diaion HP-20, Sephadex LH-20 and YMC-gel (ODS-A) column chromatography and then isolated as a colorless powder. Poststatin has the molecular formula C26H47N5O7. The IC50 value of poststatin against the PEP of partially purified porcine kidney was 0.03 microgram/ml. It has low acute toxicity. No deaths occured after iv injection of 250 mg/kg of this agent to mice.     

Combination splitting using both in situ and ex situ techniques in triple split liver transplantation in pigs

In situ splitting of cadaver livers has been reported to reduce cold ischemic damage, to avoid biliary complications, and to result in improved graft survival. In this study, which involved a wider application of split liver transplantation (SLT), we examined the effects of a technique combining both ex situ and in situ splittings in triple SLT in pigs and compared it to ex situ splitting alone. In the combination splitting group, the splitting between the right and left lobes was done in situ with perfusion of the left lobe with cold, lactated Ringer's solution; that between the lateral and medical right lobes was done ex situ in backtable surgery. The time required for in situ splitting was 28 ± 5 min. The time for backtable surgery and the total ischemia time were significantly shorter in the combination splitting group than that in the ex situ splitting group (P < 0.05). One day after triple SLT, the elevations in both serum AST and LDH in the ex situ splitting group were significantly greater than those in the combination splitting group (P < 0.05). We conclude that combination splitting may provide a technical improvement and have a beneficial effect on the clinical application of triple SLT. Received: 21 October 1997 Received after revision: June 9, 1998 Accepted: July 8, 1998     

C-13 beta-acyloxymilbemycins, a new family of macrolides. Discovery, structural determination and biological properties.

A family of novel milbemycins possessing C-13 beta-acyloxy substitution was produced by Streptomyces hygroscopicus ATCC 53718. These compounds were detected by HPLC diode array analysis and possess anthelmintic and ectoparasiticidal activity. The origin of the oxygen atom at C-13 is discussed.     

The usefulness of diving reflex--the effect on PSVT

We attempted to use the diving reflex to treat PSVT in five patients, in whom carotid-sinus massage had failed to terminate, PSVT. In three cases PSVT converted to normal sinus rhythm. The patient was seated comfortably, and a pan of ice and water (4 degrees C) was placed on the table in front of the patient. He then took a deep breath and, without expiration, submerged his face in the cold ice and water for about 30 seconds. In case 1, a 68-year-old male, PSVT stopped after facial immersion of 11 seconds. Subsequently, sinus arrest with junctional or ventricular contractions continued for 7 seconds followed by conversion to the sinus rhythm. The duration of facial immersion was 18 seconds. In case 2, a 51-year-old male, PSVT converted to the sinus rhythm in the same way. The duration of facial immersion was 23 seconds. Case 3 was a 27-year-old female with WPW syndrome. PSVT converted to the sinus rhythm after a 6.6 seconds facial immersion. Case 4 and 5 were respectively 72 and 73-year-old males, whose attacks did not respond to the diving reflex for the reason that they could not maintain breath-holding for a sufficient time to activate the reflex adequately. We postulated that apnea might effect the termination of PSVT in case 1 and 2 because relatively long duration of about 20 seconds was necessary to convert PSVT to the sinus rhythm. On the other hand, in case 3, cold water stimulation on the face might play an important role because PSVT converted to the sinus rhythm immediately.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cryopreservation of hamster pancreatic islets using a rapid cooling rate

To clarify the possibility of developing a rapid colling rate for islet cryopreservation, we used a cooling rate of 25°C/min for hamster pancreatic islet cryopreservation using 15 per cent dimethylsulfoxide as a cryoprotectant. After preservation, these islets were examined for their morphology and function by assaying the insulin release after glucose stimulation and the contents of the insulin and DNA in 10 islets. In addition, islet cell replicatory activity was investigated by an autoradiographic technique. The effects of transplantation of the islets upon isogeneic and xenogeneic transplantation were also examined. Freezing using a rapid cooling rate of 25°C/min was found to be as effective as a slow cooling rate of 1°C/min for hamster islet cryopreservation. Morphologically, the cryopreserved islets appeared to be similar to the non-frozen cultured islets. The glucose-stimulated insulin release and cell replicatory activitiesin vitro also remained unchanged, whereas the number of cells per islet decreased slightly after cryopreservation. The grafting of cryopreserved islets normalized streptozotocin induced hyperglycemia following isogeneic transplantation. On the other hand, no prolongation of graft survivals in the case of the xenogeneic transplantation of hamster islets to rats was observed. The isogeneically transplanted islets exhibited the same cell replicatory activitiesin vivo, which was even higher compared that of normal hamster pancreatic isletsin situ. In conclusion, the present findings indicate that hamster pancreatic islets can be successfully cryopreserved using a rapid cooling rate, however, it does not appear that this treatment reduces islet vulnerability to xenogeneic graft rejection.