Search PubMed⌕ Search

Biomedical subjects

G Damia

Publications and source records attributed to G Damia.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Caridex--conscious sedation association. A new approach in pedodontics].

Psycological approach and analgesia are very important in paediatric dentistry. Sometimes the first is not enough and it is necessary the use of pharmacological methods. They are represented with sure and useful technique like "relative analgesia" with N2O/O2. The use of Caridex method is also very good in operative paediatric dentistry because there is not the necessity of local anesthesia with injection and the use of burns and drills. The AA. have connected together these two methods, and they present some very interesting clinical reports. With Caridex it's possible to remove only decayed dentine saving so the healthy dentine and reducing fear and stress in very young children. The association with relative analgesia permits to do a very early and global therapy in children also very young (24-36 months). The AA. have obtained a reduction of hemotivity, of odontogenous stress, and last but not least with this method there is the opportunity to avoid the general anesthesia.

Aminobutyrates↗
PubMed1989

Characterization of a novel mouse reticular cell sarcoma M5076 subline resistant to cisplatin.

A novel murine tumor resistant to cis-diamminedichloroplatinum (cisplatin, DDP) was obtained (M5/DDP) after 22 passages in which mice bearing the ovarian reticular cell sarcoma M5076 (M5) were treated with DDP. Although DDP conserved some inhibitory activity on growth of M5/DDP, it was much less effective than on M5. Treatment with DDP did not prolong the survival time of mice with M5/DDP, whereas it markedly prolonged survival of M5-bearing mice. M5 and M5/DDP tumors shared many biological and biochemical features. They were similar histologically, they metastasized reproducibly to the liver and were poorly immunogenic. Their growth rates were comparable; their DNA index, percentage of cells in S phase and intra-cellular glutathione content were also similar. In both tumors, DDP caused an accumulation of cells in S late-G2-M within 24 hr after drug treatment. However, this was efficiently reversed in M5/DDP, whereas it worsened and persisted longer in M5. Cross-resistance was observed between DDP and its analogues carboplatin and iproplatin, but tetraplatin retained marginal activity on M5/DDP tumor. Several alkylating agents tested [L-phenyalanine mustard (L-PAM); cyclophosphamide (CTX); chlorambucil (CLB); 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and dacarbazine (DTIC)] were not totally cross-resistant to DDP, but showed greater activity on M5 than on M5/DDP. Other non-alkylating anti-neoplastic drugs showed a similar degree of activity on M5 and M5/DDP. 5-Aza-2'-deoxycytidine (Aza-d-Cyd) was very effective on both tumors, etoposide (VP-16) and cytosine arabinoside (Ara-C) had no activity and Adriamycin (ADR) was weakly effective.

Animals↗
PubMed1989

Lymphokine-activated killer (LAK) and monocyte-mediated cytotoxicity on tumor cell lines resistant to antitumor agents.

In this study we have examined the susceptibility of tumor cell lines exhibiting different patterns of resistance to chemotherapeutic agents, to the cytotoxic action of lymphokine-activated killer (LAK) cells and activated monocytes. The susceptibility of tumor cells with pleiotropic drug resistance to these cytotoxic mechanisms was not different from that of their parental, chemo-sensitive cell lines. Tumor lines used in this study included three human cell lines (LOVO N and LOVO/Dx, I-407 and I-407/Dx, MCF7 and MCF7a) selected for being resistant to doxorubicin and showing a pleiotropic pattern of resistance, and the murine ovarian reticulum cell sarcoma M5076 and its variants resistant to individual antitumor agents (cisplatin, cyclophosphamide and 5-aza-2'-deoxycytidine). These results demonstrate that drug-resistant tumor cell lines, irrespective of the pattern of resistance, were susceptible to the in vitro cytotoxicity mediated by LAK cells and activated monocytes with levels of lysis similar to those of parental chemosensitive lines. Moreover, freshly isolated tumor cells from ovarian cancer patients unresponsive to different chemotherapeutic treatments (operationally drug-resistant) were significantly killed in vitro by LAK cells. These findings support the concept that activated effector cells have the potential to complement conventional chemotherapy by eliminating drug-resistant tumor variants.

Animals↗
PubMed1989

[Evaluation of plasma carnitine levels after orthotopic transplantation of the liver].

Variations in plasma levels of total carnitine (TC), free carnitine (FC), and acyl-carnitine (AC) were studied in 10 patients undergoing orthotopic liver transplantation. The postoperative values were higher than the preoperative ones and positively related to time flow. As exogenous carnitine was not supplied during the study, these data suggested a better biosynthetic activity in the transplanted liver, in spite of standard blood tests results. No positive correlation between carnitine levels and variations in serum transaminases, bilirubin, cholestasis related enzymes, pre-albumin and albumin supply was found. Carnitine plasma levels were not influenced either by nutritional caloric input or by methionine and lysine inputs. Our results show that variations in carnitine plasma levels are a specific and responsive index of functional recovery in the transplanted liver.

Adult↗
PubMed1988

A new active model lung.

A new model lung with the capacity for simulated spontaneous breathing is described. It consists of a modified commercial mechanical ventilator (Kontron ABT 4100), connected in parallel to a compliant system, a cylindric acrylic box with a latex thin membrane substituting for the top. Volume and compliance of the model are 2500 ml and 50 ml cmH2O-1, respectively. The modified ventilator simulates physiologic inspiratory flow at a rate of 10 to 30 min-1 and tidal volume up to 1000 ml, with an inspiratory to expiratory time ratio continuously variable between 1:4 and 4:1. The model has been tested under different respiratory assist techniques, connected either to continuous positive airway pressure proved to be reliable, versatile and bearing satisfactory resemblance to human ventilatory physiology.

Humans↗
PubMed1988

Dose-dependent pharmacokinetics of flavone acetic acid in mice.

The pharmacokinetics of the novel anticancer agent, flavone acetic acid (FAA) were investigated in Balb-c mice treated with i.v. doses of 100 mg/kg or 300 mg/kg, using an HPLC assay. The kinetics of disappearance from plasma was monoexponential and dose-dependent. After 100 mg/kg, the plasma peak level was 250 +/- 11 micrograms/ml, t1/2 was 0.5 h, and AUC was 309 micrograms/ml per h. After 300 mg/kg, the plasma peak level was 710 +/- 57 micrograms/ml, t1/2 was 2.1 h, and the area under the curve (AUC) 1771 micrograms/ml h. Mouse plasma protein binding of FAA was about 70%. As is the case with plasma, in all tissues analyzed, the FAA-AUC values were disproportinately greater after 300 mg/kg than after 100 mg/kg. The highest drug concentrations were found in the liver and small intestine; concentrations were intermediate in lung, heart, and spleen, and lowest in brain. Less than 5% of the FAA dose was eliminated as unchanged drug in the stool. Total excretion of FAA as unchanged drug in the urine collected up to 96 h after drug treatment corresponded to 75% and 60% of the i.v. doses of 100 and 300 mg/kg, respectively. A minor fraction of FAA dose, corresponding to 1% and 6% of the two doses, was eliminated in the urine as a FAA glucuronide or sulfate.

Animals↗
PubMed1988

Response of chemically induced primary colon tumours of the mouse to flavone acetic acid (NSC 347 512).

Flavone acetic acid (FAA) is a compound with proven activity against various transplantable colon cancers in mice. In this study it was evaluated against primary colon tumours, chemically induced by methylazoxymethanol in outbred CF1 mice. FAA was given i.v. at doses of 70 or 100 or 150 mg kg-1 every 7 days for 6 weeks. Only 4 out of 60 FAA treated mice died of toxicity. FAA reduced tumour number and tumour burden compared to control mice (P less than 0.05 at least), with no apparent dose-response relationship. Antitumour activity of FAA was comparable to that of 5-fluorouracil (5-FU) used as standard. Moreover, FAA was more effective that 5-FU against large tumours. FAA levels in plasma and different tissues (including colonic neoplastic lesions) after a single i.v. dose of 150 mg kg-1 were investigated. Tumour FAA levels appear insufficient to be responsible for the antitumour activity based only on a direct FAA cytotoxic effect. The results confirm clinical interest in FAA and suggest that mechanisms other than direct cytotoxicity may be involved in its activity.

Animals↗
PubMed1988

Response to flavone acetic acid (NSC 347512) of primary and metastatic human colorectal carcinoma xenografts.

The antitumour activity of flavone acetic acid (FAA) was evaluated against two human colorectal carcinoma (HCC) lines, HCC-P2988 and HCC-M1410, transplanted into nude mice. On repeated i.v. injection of 200 mg kg-1 every 4 days FAA was moderately active against the s.c. growing HCC-P2988. HCC-M1410 transplanted s.c. was almost unresponsive in the same experimental conditions. In contrast, FAA (200 mg kg-1 i.v. every 4 days, repeated three times) significantly reduced liver tumour colonies produced by the HCC-M1410 cells injected intrasplenically into nude mice. These findings suggest that FAA has potential activity against human colorectal carcinoma, particularly against liver metastases.

Animals↗
PubMed1988

Perioperative changes in functional residual capacity in morbidly obese patients.

Functional residual capacity (FRC) was measured before and after induction of anaesthesia for jejunoileal bypass surgery in 30 morbidly obese patients. The onset of anaesthesia was associated with a 51% reduction in FRC from 2.2 litre to 1.0 litre. Eighteen of the patients were investigated more extensively; in these subjects FRC was reduced below the control values of residual volume (RV) with the onset of anaesthesia, but recovered towards baseline after laparotomy incision. Reduction in FRC is related to baseline vital capacity (VC) and FRC and is much greater than that reported for patients of normal weight.

Adult↗
PubMed1986

Main nitrogen balance determinants in malnourished patients.

Factors influencing nitrogen balance during total parenteral nutrition have been investigated in 38 malnourished patients studied for a cumulative period of 280 days. According to multiple regression analysis, nitrogen intake (0.213 +/- 0.004 g kg-1 day-1, mean +/- SD) proved to be the major determinant of a positive nitrogen balance (0.018 +/- 0.004 g kg-1 day-1), followed by non-protein energy intake (43.3 +/- 0.5 kcal kg-1 day-1). Total calorie intake to predicted basal energy expenditure and non protein calorie to nitrogen ratios appeared to have little significance on nitrogen balance, when corrected for the two former variables.

Female↗
PubMed1986

Different sensitivity of two Walker 256 carcinoma lines to cyclophosphamide: correlation with drug distribution, biotransformation and macromolecule binding.

Two closely related lines of the same Walker 256 carcinoma in Crl-CD/COBS rats, described as behaving differently as regards tumor growth and host reaction, show different chemotherapeutic sensitivity to cyclophosphamide (CPA). Line B, which induces early cachexia with marked anorexia, is only moderately sensitive to CPA, while line A, which causes mild anorexia and only terminal cachexia, shows marked responsiveness to CPA, cure being attained in 75% of animals treated with a single dose of 120 mg/kg and in 90-100% of those given 20 mg/kg every other day. Comparative studies in both tumor lines on the distribution of CPA in vivo and on its metabolism by the liver perfusion technique showed no appreciable differences between the two lines in the pharmacokinetics of the compound, but indicate a much greater metabolizing capacity of CPA in the Walker 256/A animals. In vitro metabolic and covalent binding studies confirm that the liver of the Walker 256/A group metabolizes and covalently binds twice as much CPA as the liver of the Walker 256/B group. Conversely to Walker B, microsomal preparations of the Walker tumor line A are able to metabolize CPA to intermediates which irreversibly bind to tissue macromolecules, suggesting an in situ activation of the compound in the sensitive Walker tumor.

Animals↗
PubMed1986

Parenteral nutrition of injured patients.

Injured patients treated with fructose 1,6-diphosphate (1 millimole of phosphate per kilogram per day) together with parenteral nutrition had a better nitrogen balance than patients treated with isocaloric nutrition and an inorganic source of phosphate. Excretion of 3-methylhystidine was similar while tyrosine and alanine output from the extremities was lower in the group of patients given fructose 1,6-diphosphate. The data indicates that the protein sparing action of fructose 1,6-diphosphate is exerted through an increased protein synthesis.

Abdominal Injuries↗