Identification of Ruscus steroidal saponins by HPLC-MS analysis.

A novel HPLC-UV method has been developed for the fingerprint analysis of the steroidal saponins in the rhizomes of three Ruscus species (Ruscus aculeatus, Ruscus hypoglossum and Ruscus colchicus). Saponins were identified by HPLC-ESI-MS. During the study a new major saponin was detected in the rhizomes of R. hypoglossum and R. colchicus. The structure of the new compound was defined as 1-O-[alpha-L-rhamnopyranosyl-(1-->2)-6-O-acetyl-beta-D-galactopyranosyl]-1beta,3beta,22xi,26-tetrahydroxy-furost-5(6)-en-26-O-beta-D-glucopyranoside (8) by spectral analysis.

Modulation of human platelet function by L-canavanine: differential effects of low and high concentrations.

L-Canavanine is a naturally occurring L-amino acid that interferes with L-arginine-utilizing enzymes owing to its structural analogy with this L-amino acid. In macrophages and polymorphonuclear leukocytes, which express inducible nitric oxide synthase (iNOS), L-canavanine is able to prevent the L-arginine-derived synthesis of nitric oxide (NO). Its effects on constitutive NOS (cNOS) are far less clear. Because human platelets synthesize NO from L-arginine through a cNOS and because intracellular NO levels modulate platelet function, we have investigated the effects of L-canavanine on parameters potentially influenced by NO, such as platelet levels of 3',5'-cyclic guanosine monophosphate (cGMP) and responses to different aggregating agents. In our experimental conditions, L-canavanine was able to influence the response of human platelets to different aggregating agents such as catecholamines, 5-hydroxytryptamine, and ADP. Low L-canavanine concentrations (10-100 micromol/l) decreased platelet responses, whereas a high concentration (1 mmol/l) was unable to exert antiaggregating effects. In resting platelets, L-canavanine reduced the levels of cGMP, starting from a concentration of 1 mmol/l; furthermore, at the same concentrations, it was able to reduce cGMP levels at the end of the aggregation induced by collagen. In conclusion, L-canavanine exerts differential effects on human platelets in relation to the concentrations: at low levels, it exerts antiaggregating effects by actions independent of NOS inhibition, whereas, at high levels, it inhibits NO synthesis and does not exert antiaggregating effects.

Relationship between nutritional status and tumor growth in humans.

AIMS AND BACKGROUND: There is considerable evidence from studies on tumor-bearing animals that nutritional support aimed at maintaining a good nutritional status can indeed promote tumor growth. Experience in humans, however, is scanty and controversial, this issue never having been extensively investigated. The purpose of this study was to analyze whether there exists a relationship between nutritional status and tumor growth in patients with non-Hodgkin's lymphoma. The hypothesis behind it was that if it is true than an abundant availability of substrates promotes tumoral growth, then the better the nutritional status the higher the tumor cell proliferation. METHODS: Two hundred and forty six adult patients with non-Hodgkin's lymphoma were characterized according to nutritional status (percent of weight loss as compared to usual body weight, serum albumin, serum cholinesterase, number of lymphocytes) and rate of incorporation of 3H thymidine labelling index in the tumor tissue. The values of serum albumin, serum cholinesterase and lymphocytes were subdivided into three classes adopting as cut-off points the tertile values of their distribution, while weight loss was scored as a "no" and a "yes". The association between nutritional parameters and labelling index was evaluated by a univariate analysis (X2 test and Mantel-Haenszel X2 test and the odds ratio) and by a logistic multiple regression model. RESULTS: Results of the univariate analysis show a statistically significant association between "poor" nutritional status (depressed nutritional indexes) and "high" labelling index (increased tumoural growth), while the multiple regression analysis found that the only significant association was that between low serum cholinesterase and high labelling index. CONCLUSIONS: These data demonstrate for the first time in a large series of patients that maintenance of a good nutritional status does not have any deleterious effect on the tumor growth.

Cavitron Ultrasonic Surgical Aspirator (CUSA) in liver resection.

At the Istituto Nazionale Tumori of Milan, the Cavitron Ultrasonic Surgical Aspirator (CUSA) was employed to perform hepatic resections in 34 patients with primary or secondary liver tumors. The use of CUSA has proved to be very efficient and safe. In lobectomies and extended lobectomies average bleeding was 685 cc with a mean resection time of 28 minutes. In segmentectomies, average bleeding was 540 cc with a mean resection time of 22 minutes. Comparing these data with those we previously obtained in hepatic resections using traditional methods (digitoclasia), it appears that despite overall operative times suffering no significant variation, a considerable reduction in bleeding was obtained, together with a notable fall in post-operative complications.

[Possibility of using intracavitary perfusion hyperthermia in the treatment of gastric cancer: an study of its local and systemic effects]. / Possibilità di impiego dell'ipertermia perfusionale endocavitaria nel trattamento del cancro gastrico: studio dei suoi effetti locali e sistemici.

The selective lethal effect of heat on neoplastic cells has been demonstrated by several experiments "in vitro" and "in vivo". In this paper the authors report their experience on endocavitary-hyperthermic perfusion of the stomach, performed with a hyperthermic-perfusion system invented and built by them. 12 rabbits were submitted to hyperthermic perfusion of the stomach at 42.5 C for a period of 50 minutes under general anesthesia. Three other rabbits were treated with normothermic perfusion for a further control. Rectal temperature was monitored during perfusion and gastric pH was evaluated after treatment by a gastrectomy. Neither death nor major complications were observed during and after treatment and physiologic functions were maintained. Animals were sacrificed at different times from the treatment and macroscopic and microscopic exams of the principal organs were performed. Edema of the gastric wall was present in rabbits killed after a short time from treatment, while it was absent in animals sacrificed after a longer time; in these animals normal aspect of gastric glands and no fibroblastic activity was evident. The authors consider the possibility of employing this treatment in curing advanced gastric cancer, eventually associated with hyperthermic perfusion of abdominal cavity.