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F Cavaliere

Publications and source records attributed to F Cavaliere.

At least 37 records · Page 2Linked to original sources

P2 receptor modulation and cytotoxic function in cultured CNS neurons.

In this study we investigate the presence, modulation and biological function of P2 receptors and extracellular ATP in cultured cerebellar granule neurons. As we demonstrate by RT-PCR and western blotting, both P2X and P2Y receptor subtypes are expressed and furthermore regulated as a function of neuronal maturation. In early primary cultures, mRNA for most of the P2 receptor subtypes, except P2X(6), are found, while in older cultures only P2X(3), P2Y(1) and P2Y(6) mRNA persist. In contrast, P2 receptor proteins are more prominent in mature neurons, with the exception of P2Y(1). We also report that extracellular ATP acts as a cell death mediator for fully differentiated and mature granule neurons, for dissociated striatal primary cells and hippocampal organotypic cultures, inducing both apoptotic and necrotic features of degeneration. ATP causes cell death with EC(50) in the 20-50 microM range within few minutes of exposure and with a time lapse of at most two hours. Additional agonists for P2 receptors induce toxic effects, whereas selected antagonists are protective. Cellular swelling, lactic dehydrogenase release and nuclei fragmentation are among the features of ATP-evoked cell death, which also include direct P2 receptor modulation. Comparably to P2 receptor antagonists previously shown preventing glutamate-toxicity, here we report that competitive and non-competitive NMDA receptor antagonists inhibit the detrimental consequences of extracellular ATP. Due to the massive extracellular release of purine nucleotides and nucleosides often occurring during a toxic insult, our data indicate that extracellular ATP can now be included among the potential causes of CNS neurodegenerative events.

Adenosine Triphosphate↗

Cerebellar lesion up-regulates P2X1 and P2X2 purinergic receptors in precerebellar nuclei.

ATP released in the extracellular space by neuronal injury can influence neighboring neurons via activation of purinergic receptors. In vitro data suggest the involvement of ATP and purinergic receptors as trophic agents in different biological events such as neuritogenesis and cell survival. Recently, in vivo studies have demonstrated modifications in the glial expression of ionotropic purinergic receptors after CNS lesions. In the present study, we investigated the effects of CNS lesion on the neuronal expression of P2X(1) and P2X(2) receptor subunits by immunohistochemistry and western blotting techniques. In the precerebellar structures of normal animals the expression of P2X(1) and P2X(2) was lower than previously reported. P2X(1) immunostaining was confined only to fibers, while P2X(2) immunostaining demonstrated a neuronal expression. After unilateral cerebellar lesion (hemicerebellectomy) axotomized precerebellar neurons underwent marked cell loss; however, some precerebellar neurons did not degenerate. Seven to 35 days after hemicerebellectomy, a transient, time-dependent, marked increase in the number of immunopositive P2X(1) and P2X(2) neurons was observed in the precerebellar nuclei of the experimental side. An even distribution of immunopositive neurons was present in almost all precerebellar nuclei examined, except for the inferior olive. In this latter structure, differences in the distribution of immunopositive neurons were evident among the subnuclei. Up-regulation of immunoreactivity over relatively long time periods, distribution selectivity and absence of degenerating morphological features in immunopositive neurons suggest that purinergic receptors may have a role in mediating the survival of neuronal responses to axotomy. The present findings are the first report in the CNS of P2X(1) and P2X(2) receptor subunit involvement in neuronal reaction to axotomy. They provide in vivo evidence of a correlation between purinergic receptor subunit up-regulation and survival of injured neurons.

Animals↗

Curcumin inhibits activation of Vgamma9Vdelta2 T cells by phosphoantigens and induces apoptosis involving apoptosis-inducing factor and large scale DNA fragmentation.

Curcumin, in addition to its role as a spice, has been used for centuries to treat inflammatory disorders. Although the mechanism of action remains unclear, it has been shown to inhibit the activation of NF-kappaB and AP-1, transcription factors required for induction of many proinflammatory mediators. Due to its low toxicity it is currently under consideration as a broad anti-inflammatory, anti-tumor cell agent. In this study we investigated whether curcumin inhibited the response of gammadelta T cells to protease-resistant phosphorylated derivatives found in the cell wall of many pathogens. The results showed that curcumin levels > or =30 microM profoundly inhibited isopentenyl pyrophosphate-induced release of the chemokines macrophage inflammatory protein-1alpha and -1beta and RANTES. Curcumin also blocked isopentenyl pyrophosphate-induced activation of NF-kappaB and AP-1. Commencing around 16 h, treatment with curcumin lead to the induction of cell death that could not be reversed by APC, IL-15, or IL-2. This cytotoxicity was associated with increased annexin V reactivity, nuclear expression of active caspase-3, cleavage of poly(ADP-ribose) polymerase, translocation of apoptosis-inducing factor to the nucleus, and morphological evidence of nuclear disintegration. However, curcumin led to only large scale DNA chromatolysis, as determined by a combination of TUNEL staining and pulse-field and agarose gel electrophoresis, suggesting a predominantly apoptosis-inducing factor-mediated cell death process. We conclude that gammadelta T cells activated by these ubiquitous Ags are highly sensitive to curcumin, and that this effect may contribute to the anti-inflammatory properties of this compound.

Adult↗

Hypoglycaemia-induced cell death: features of neuroprotection by the P2 receptor antagonist basilen blue.

Our previous work in neuronal cultures has shown that several antagonists of P2 ATP receptors prevent cell death evoked by hypoglycaemia, chemical hypoxia, mitochondria dysfunction, as well as glutamate-dependent excitotoxicity and low potassium-induced apoptosis. Experiments are now designed to examine which biological pathway contributes to cell death/survival under glucose starvation. We show here that, consequently to hypoglycaemic insults, cerebellar granule neurones undergo a combination of apoptosis and necrosis both inhibited by the P2 receptor antagonist basilen blue. This is demonstrated by morphological and biochemical features, such as TdT-mediated dUTP-biotin nick end-labelling, fluorescent staining of nuclear chromatin using Hoechst 33258, direct counting of intact viable nuclei and extracellular releasing of the cytosolic enzyme LDH. Furthermore, we show that hypoglycaemia induces outflow of cytochrome c from mitochondria and it up-regulates heat-shock proteins HSP70, but not HSP90, glucose-regulated proteins GRP75 and GRP78, as well as expression and activity of the enzyme caspase-2. Basilen blue can modulate only some of these effects. Our data contribute to dissect the role played by P2 receptor antagonism in sustaining neuroprotection against metabolic stresses.

Animals↗

Glucose deprivation and chemical hypoxia: neuroprotection by P2 receptor antagonists.

In this work we investigate cell survival after glucose deprivation and/or chemical hypoxia and we analyse the neuroprotective properties of selected antagonists of P2 ATP receptors. We find that in rat cerebellar granule neurones, the antagonist basilen blue prevents neuronal death under hypoglycaemia. Basilen blue acts through a wide temporal range and it retains its efficacy under chemically induced hypoxic conditions, in the presence of the respiratory inhibitors of mitochondria electron transport chain complexes II (3-nitropropionic acid) and III (antimycin A). In spite of the presence of these compounds, basilen blue maintains normal intracellular ATP levels. It furthermore prevents neuronal death caused by agents blocking the mitochondrial calcium uptake (ruthenium red) or discharging the mitochondrial membrane potential (carbonyl cyanide m-chlorophenylhydrazone). Inhibition of poly (ADP-ribose) polymerase, modulation of the enzyme GAPDH and mitochondrial transport of mono-carboxylic acids are not conceivable targets for the action of basilen blue. Survival is sustained by basilen blue also in CNS primary cultures from hippocampus and in PNS sympathetic-like neurones. Partial neuroprotection is furthermore provided by three additional P2 receptor antagonists: suramin, pyridoxal-phosphate-6-azophenyl-2',4'-disulphonic acid 4-sodium and 4,4'-diisothiocyanatostilbene-2,2'disulphonic acid. Our data suggest the exploitation of selected P2 receptor antagonists as potential neuroprotective agents.

Adenosine Triphosphate↗

Interaction between ATP and nerve growth factor signalling in the survival and neuritic outgrowth from PC12 cells.

In a previous study we used P2 receptor antagonists to inhibit diverse responses that nerve growth factor (NGF) promotes and coordinates in PC12 cells and we suggested that P2 receptors partake in the NGF signalling cascade. In this paper, we examine the direct role of extracellular P2 receptor agonists as neurotrophic factors. ATP and 2-Cl-ATP promote neurite regeneration after priming PC12 cells with NGF and the effect is dose-dependent, with an EC(50) of about 5 and 3 microM, respectively. The number of cell clumps bearing neurites was maximally induced in day 1 and it was maintained up to about one week by ATP, or up to at least 2 weeks by 2-Cl-ATP. The involvement of P1 receptors or intracellular inosine in these actions was excluded, whereas various antagonists of P2 receptors were inhibitory. Moreover, NGF and ATP caused a direct up-regulation of P2X(2), P2X(3), P2X(4) and P2Y(2), but not P2Y(4) receptor proteins under neurite-regenerating conditions, as well as extracellular signal-regulated kinase (Erk)1-2 tyrosine/threonine phosphorylation and activation. Finally, ATP, 2-Cl-ATP and ATPgammaS enhanced neurite initiation evoked by sub-optimal NGF concentrations and ATP and 2-Cl-ATP fully sustained survival of PC12 cells after serum deprivation. Our results establish that P2 receptor agonists can behave as neurotrophic factors for neuronal cells and suggest a potential interplay between ATP and NGF in the signalling pathways triggered on their target cells.

Adenosine Triphosphate↗

New agents for sedation in the intensive care unit.

Several advances are likely to benefit the ICU patient requiring sedation, analgesia, and anxiolysis. The cooperative sedation induced by dexmedetomidine is a unique and valuable state that allows patients to be aroused easily and interferes little with ventilation. Remifentanil is the prototype of short-acting drugs, providing fast onset and offset; its relatively high cost may be balanced by limiting the risk for long-lasting respiratory depression. Lorazepam seems to be finding more proponents, especially in long-term ICU sedation where the costs of the newer agents may be prohibitive.

Adrenergic alpha-Agonists↗

Antagonists of P2 receptor prevent NGF-dependent neuritogenesis in PC12 cells.

The pheochromocytoma PC12 cell line that develops neuronal characteristics of sympathetic cells after treatment with nerve growth factor (NGF) represents a well-established cellular model system for studying NGF signalling. Interesting information on the different mechanistic pathways of NGF can be obtained by adopting the pharmacological approach of inhibiting P2 receptors, expressed in naive PC12 cells and recognised as important biological mediators of neurotransmitters and growth factors. We show here that Basilen Blue, an antagonist of P2 receptor, reversibly prevents NGF-dependent neurite outgrowth with an IC(50) in the 5-10 microM range. Suramin, oxidised-ATP and diisothiocyanatostilbene-disulfonic acid, differently from other purinoceptor ligands, are also effective in this regard. NGF-dependent regeneration and stability of neurites, selected NGF-dependent extracellular and intracellular protein phosphorylations, binding of [(3)H] ATP to PC12 cell membranes are also modulated by Basilen Blue. On the contrary, cell adhesion, cellular duplication, 5'-nucleotidase activity, NGF-induced tyrosine autophosphorylation of TrkA receptors are not affected. NGF furthermore directly modulates the extracellular release of ATP and especially the levels of P2X(2) receptor protein in PC12 cells. In addition, extracellular ATP improves the neuritogenic effect of sub-optimal concentrations of NGF. Our study identifies P2 receptor ligands, particularly Basilen Blue, as useful tools to dissect different NGF-evoked functions, suggesting a mechanistic role for P2 receptors in the signalling pathways of NGF.

5'-Nucleotidase↗

Treatment of peritoneal carcinomatosis with intent to cure.

BACKGROUND AND OBJECTIVES: Low-grade malignant tumors arise in the abdomen, do not infiltrate, and "redistribute" on the peritoneum with no extraregional spreading. In these cases, aggressive surgery combined with localized chemotherapy may provide cure. METHODS: After removing the tumor with the regional peritoneum en bloc, intraabdominal hyperthermic chemoperfusion was performed throughout the abdominopelvic cavity. Alternatively, early intraabdominal chemotherapy, starting on the first postoperative day, was administered for 5 days. RESULTS: Forty patients affected with extensive peritoneal carcinomatosis underwent peritonectomy, with no residual macroscopic disease except in four cases. Seventy-five percent of the patients underwent locoregional chemotherapy. Major complications were observed in 40% of the patients and led to death in five; there was a direct correlation to the duration of surgery (P = 0.03). At a mean follow-up of 20 months, the overall 2-year survival was 61.4%, with a median survival of 30 months. CONCLUSIONS: After a learning curve of 18 months, the feasibility of the integrated treatment increased to greater than 90%, and mortality dramatically decreased. The combined treatment resulted in a high survival rate in patients with extensive carcinomatosis who were no longer responsive to traditional therapies.

Antineoplastic Combined Chemotherapy Protocols↗

Topical use of tranexamic acid in coronary artery bypass operations: a double-blind, prospective, randomized, placebo-controlled study.

OBJECTIVES: We sought to investigate the effect of topical application of tranexamic acid into the pericardial cavity in reducing postoperative blood loss in coronary artery surgery. METHODS: A prospective, randomized, double-blind investigation with parallel groups was performed. Forty consecutive patients undergoing primary coronary surgery were randomly assigned to group 1 (tranexamic acid group) or group 2 (placebo group). Tranexamic acid (1 g in 100 mL of saline solution) or placebo was poured into the pericardial cavity and over the mediastinal tissues before sternal closure. The drainage of mediastinal blood was measured hourly. RESULTS: Chest tube drainage in the first 24 hours was 485 +/- 166 mL in the tranexamic acid group and 641 +/- 184 mL in the placebo group (P =.01). Total postoperative blood loss was 573 +/- 164 mL and 739 +/- 228 mL, respectively (P =.01). The use of banked donor blood products was not significantly different between the two groups. Tranexamic acid could not be detected in any of the blood samples blindly collected from 24 patients to verify whether any systemic absorption of the drug occurred. There were no deaths in either group. None of the patients required reoperation for bleeding. CONCLUSIONS: Topical application of tranexamic acid into the pericardial cavity after cardiopulmonary bypass in patients undergoing primary coronary bypass operations significantly reduces postoperative bleeding. Further studies must be carried out to clarify whether a more pronounced effect on both bleeding and blood products requirement might be seen in procedures with a higher risk of bleeding.

Administration, Topical↗

Incidence of chromosomes 1 and 17 aneusomy in breast cancer and adjacent tissue: an interphase cytogenetic study.

BACKGROUND: Characterization of the biopathologic events underlying the early steps of breast carcinogenesis may have a dramatic impact on reducing breast cancer mortality. Genes involved in breast tumorigenesis are localized on chromosomes 1 and 17, and numeric aberrations of these chromosomes have been correlated with breast cancer tumorigenesis and progression. According to the field cancerization hypothesis, specific chromosome aberrations may be present in breast cancer and in normal-appearing adjacent tissue. The latter changes reflect the genomic damage that follows longterm carcinogenic exposure and precede the morphologically detectable neoplastic transformation. We hypothesize that detection of these aberrations in benign breast epithelium may provide a tool for molecular risk assessment. STUDY DESIGN: Using fluorescence in situ hybridization with centromere-specific probes, we determined the status of chromosomes 1 and 17 in fresh imprints of 28 samples of primary tumors and 54 samples of their surrounding uninvolved parenchyma taken from patients undergoing operations for breast carcinoma. Ten contralateral breast biopsy specimens collected from patients with previous breast carcinoma were also evaluated as a surrogate of a high-risk group to rule out the hypothesis that chromosomal aneusomy in tumor-adjacent tissue could be related to a paracrine effect of the primary tumor. Ten samples of benign breast tissue taken from patients at low risk were used as controls to define tolerance limits for aneusomy definition. RESULTS: Using threshold values of 40% of signal loss and 13% of signal gain to define chromosome aneusomy (ie, mean + 3 SDs of the control group signals), we found the following: 1) almost all primary breast tumors were aneusomic for chromosomes 1 and 17; 2) primary breast tumor and adjacent uninvolved parenchyma shared the same pattern of chromosomes 1 and 17 aneusomy in 66.7% of patients; and 3) chromosomes 1 and 17 aneusomies in contralateral benign breast samples from high-risk patients were not different from those in primary breast tumor or adjacent tissue samples. CONCLUSIONS: These results suggest that chromosomes 1 and 17 aneusomy may represent an intermediate biomarker of breast tumorigenesis potentially useful to detect patients at high risk of breast carcinoma who may benefit from preventive interventions.

Adult↗

Peritonectomy and hyperthermic antiblastic perfusion in the treatment of peritoneal carcinomatosis.

AIMS: Some low-grade malignant tumours arising in the abdomen tend to remain loco-regionally confined to peritoneal surfaces, without systemic dissemination. In these cases complete surgical tumour cytoreduction followed by intra- or post-operative regional chemotherapy has curative potential. The aim of this study was to evaluate the outcome for patients treated in this way. METHODS: Peritonectomy was performed, involving the complete removal of all the visceral and parietal peritoneum involved by disease. After peritonectomy, hyperthermic antiblastic perfusion was carried out throughout the abdominopelvic cavity for 90 min, at a temperature of 41.5-42.5 degrees C, with mitomycin C (3.3 mg/m2/l) and cisplatin (25 mg/m2/l) (for appendicular or colorectal primaries), or cisplatin alone (for ovarian primaries). Alternatively, the immediate post-operative regional chemotherapy was performed with 5-fluorouracil (13.5 mg/kg) and Lederfolin (125 mg/m2) (for colonic or appendicular tumours) or cisplatin (25 mg/m2) (for ovarian tumours), each day for 5 days. RESULTS: Thirty-five patients affected by extensive peritoneal carcinomatosis were submitted to peritonectomy, with no residual macroscopic disease in all cases except three. Twenty-six patients were able to undergo the combined treatment involving loco-regional chemotherapy. Complications were observed in 54% of the patients and led to death in four of them. At a mean follow-up of 17 months overall 2-year survival was 55.2%, with a median survival of 26 months. CONCLUSIONS: After a learning curve of 18 months the feasibility of the integrated treatment increased to more than 90%, while mortality decreased dramatically. The curative potential of the combined therapeutic approach seems high in selected patients with peritoneal carcinomatosis not responding to systemic chemotherapy. Careful selection of patients can minimize the surgical risk, but the treatment should currently be reserved for clinical trials.

Adult↗

Impaired carbon dioxide transport during and after cardiopulmonary bypass.

Changes in the CO2 carrying power of blood were evaluated during and after cardiopulmonary bypass (CPB) by calculating the equation of the whole blood CO2 dissociation curve and the ratio between the arterial-venous differences of CO2 content and CO2 tension (Ra-v). Sixteen patients undergoing normothermic CPB for coronary revascularization were studied; arterial and mixed venous blood gas analyses were performed prior to CPB, at the end of first cardioplegia infusion, 25 and 45 min after CPB commencement and 10 min after the termination of CPB. After CPB commencement, the whole blood CO2 dissociation curve became flatter and did not further change during or after CPB. Ra-v decreased from 1.06 +/- 0.16 to 0.72 +/- 0.12 ml/mmHg after the start of CPB and did not change significantly during CPB; it was still 0.73 +/- 0.13 ml/mmHg after CPB. The data indicate that during CPB the amount of CO2 removed from tissues by 1 litre of blood decreases by about 30% and that impairment in CO2 transport persists after the restoration of physiological circulation. Impairment in CO2 transport is mainly caused by haemodilution, but it could be worsened by acidosis.

Adult↗

[Changes in acid-base equilibrium and CO2 output induced by bicarbonate infusion].

BACKGROUND: Bicarbonate therapy for metabolic acidosis can cause tissue hypercapnia. We tested the hypothesis that CO2 retention is initially confined to blood and that tissue hypercapnia is consequent to blood hypercapnia. METHODS DESIGN: prospective study. SETTING: general Intensive Care Unit in an University Hospital. PATIENTS: ten patients, aged 34-84, undergoing fixed mechanical ventilation for stroke, respiratory failure, polytrauma, or coma and presenting fairly stabilized circulatory condition were included in the study providing that definite exclusion criteria were absent. Sodium bicarbonate, 0.08, 0.17, and 0.25 mEq/kg, was infused in 5 minutes during stages A, B, and C. During each stage, before and after bicarbonate infusion, heart rate, arterial pressure, central venous pressure, and PetCO2 were registered and arterial and central venous haemogasanalysis were performed. CO2 output was measured during and after bicarbonate infusion and total CO2 output over basal values was calculated. RESULTS: Heart rate, arterial pressure, central venous pressure did not change in any stage, while PetCO2 increased in all. Following bicarbonate infusion, pH increased more in venous than in arterial blood and was significantly affected by the amount of bicarbonate infused. In arterial blood both PCO2 and total CO2 content (TCO2) increased. In venous blood PCO2 did not change while TCO2 increased so that arterial-venous rl CO2 difference was unaffected. CO2 output changed in no patient but two during stage A, and increased by 0.54 +/- 0.16 mL/kg during stage B and by 1.18 +/- 0.26 mL/kg during stage C so that 14.5 +/- 4.3 and 21.2 +/- 4.7% of given bicarbonate was released as CO2 through the lungs. CO2 output increased after a latency that was significantly shorter during stage C (145 +/- 51 sec) than during stage B (226 +/- 53 sec). CONCLUSIONS: Since arterial-venous TCO2 difference was unaffected and haemodynamic parameters were stable, the conclusion is drawn that CO2 and bicarbonate did not diffuse out of vascular compartment during this study. However CO2 and bicarbonate diffusion out of blood would have occurred if bicarbonate infusion had continued, because CO2 excess was released through the lungs after a latency and extended after the infusion. Consequently, tissue hypercapnia during bicarbonate infusion could probably be prevented by improving CO2 release through the lungs, i.e. by hyperventilating the patient.

Acid-Base Equilibrium↗

Hyperthermic antiblastic perfusion with alpha tumor necrosis factor and doxorubicin for the treatment of soft tissue limb sarcoma in candidates for amputation: results of a phase I study.

To improve the therapeutic effectiveness of hyperthermic antiblastic perfusion (HAP), the association of recombinant tumor necrosis factor alpha (rTNF alpha), doxorubicin, and true hyperthermia (41 degrees C) was employed for the treatment of soft tissue limb sarcoma. A dose-escalation study according to Fibonacci's modified scheme was conducted, starting with a rTNF alpha dose of 0.5-3.3 mg. The doxorubicin doses (0.7 and 1.4 mg for the upper and lower limbs, respectively) and temperature level (41 degrees C) remained unchanged. Eighteen patients have been treated thus far: 9 males and 9 females of a mean age of 33 years (range: 24-71 years). The tumor was located in the upper limb in one patient and in the lower limbs in seventeen. Only 16 patients were evaluable, as 2 refused further treatment after the perfusion. In terms of local toxicity, a grade I limb reaction was observed in 3 patients, a grade II or III in 10 patients, and a grade IV in 5 patients, showing a strict correlation between the TNF dose and the grade of limb reaction. In fact, a grade III-IV limb reaction was observed in 66.6% of the patients treated with > 1 mg of rTNF alpha. The maximum tolerable dose in association with doxorubicin and true hyperthermia (41 degrees C) was 2.4 mg. Eleven patients showed a good pathological response (> 75%) and five patients showed a partial response (> 25%-< 75%). In no case was stable or progressive disease observed. The postperfusional tumor shrinkage permitted limb-sparing surgery in 75% of the patients, all of whom were candidates for amputation before HAP. No recurrences have been observed thus far. Two patients developed regional disease: one presented with a skip femur metastasis that disappeared after radiotherapy and systemic chemotherapy; the second developed regional node involvement, requiring a radical node dissection. Another patient had pulmonary metastases, 2 months after the HAP, which were resected. At a median follow-up of 12 months, all the patients are living without disease. The results of this phase I study suggest that the association of rTNF alpha, doxorubicin, and true HAP (41 degrees C) by regional perfusion is feasible and safe at a maximum tolerable rTNF alpha dose of 2.4 mg. However, because no correlation was found between the amount of rTNF alpha and the tumor response, 1 mg is recommended as the dose able to provide a high tumor necrosis rate and low local and systemic toxicity. This association appears to play an important role in the neoadjuvant treatment of soft tissue limb sarcoma.

Adult↗

The integrated treatment of peritoneal carcinomatosis. A preliminary experience.

Some low-grade malignant tumors arising in the abdomen, lack of infiltrative attitude and "redistribute" on the peritoneum with no extraregional spreading. In this cases the complete tumor cytoreduction followed by intra- or postoperative regional chemotherapy has curative intent. Peritonectomy is the complete removal of all the parietal peritoneum and the visceral peritoneum involved by disease. After peritonectomy hyperthermic antiblastic perfusion is carried out throughout the abdomino-pelvic cavity for 60 minutes, at a temperature of 41.5 degrees C, with mitomycin C (3.3 mg/m2/Lt of perfusate) and cisplatin (25 mg/m2/Lt) (appendicular or colorectal primary), or cisplatin alone is (ovarian primary). Alternatively the immediate postoperative regional chemotherapy is performed with 5-fluorouracil (13.5 mg/Kg) and Lederfolin (125 mg/m2) (colic or appendicular tumor) or cisplatin (25 ng/m2) (ovarian tumor), each day for 5 days. Twenty patients affected by extensive peritoneal carcinomatosis (12 ovarian, 5 colonic, 1 appendicular, 1 mesothelial and 1 gastric primary) were submitted to peritonectomy with no residual macroscopic disease in all cases except three. Six patients were treated with intraoperative intra-abdominal hyperthermic antiblastic perfusion, while immediate postoperative intra-abdominal chemotherapy was given in 4 patients and systemic chemotherapy in other 5. Hospital mortality was 20%. At a mean follow-up of 11 months 14 patients are alive, 11 without disease and the median overall survival is 10.2 months. The curative potential of the combined therapeutic approach seems high in patients with peritoneal carcinomatosis from ovarian or colorectal primary not responding to systemic chemotherapy. Selection criteria of patients can strictly affect the surgical risk and the treatment has to be reserved for controlled clinical trials.

Abdominal Neoplasms↗

Red blood cell energy metabolism during cardiopulmonary bypass.

BACKGROUND: During cardiopulmonary bypass (CPB) an intracellular ATP deficit could theoretically play a role in changes of erythrocyte shape and deformability caused by mechanical trauma. We therefore studied erythrocyte energy metabolism in 12 patients undergoing normothermic CPB for myocardial revascularization. METHODS: Blood samples were collected prior to and 45 minutes after CPB beginning and analyzed for erythrocyte ATP, ADP, and AMP and their metabolites, erythrocyte NAD and NADP, plasma and whole blood lactate (Lact(p) and Lact(b) respectively), and whole blood pyruvate (Pyr(b)). RESULTS: Values were expressed as mean +/- standard deviation or median (lower and higher quartiles) on the ground of a test for normality. During CPB erythrocyte nucleotides and their metabolites did not change significantly (ATP: 60.2+/-12.1 vs. 68.3+/-13.0; ADP: 12.2+/-3.6 vs. 12.0+/-3.1; AMP: 0.43+/-24 vs. 0.44+/-0.26; adenosine: 0.063 (0.034-0.203) vs. 0.77 (0.032-0.221); inosine: 0.064 (0.023-0.072) vs. 0.075 (0.025-0.111); hypoxanthine: 0.330+/-0.272 vs. 0.367+/-0.223; xanthine: 0.193+/-0.090 vs. 0.220+/-0.095; NAD: 3.149+/-0.743 vs. 3.358+/-0.851; values in microM/mM packed red blood cell hemoglobin) while NADP increased (2.110+/-0.390 vs. 2.433+/-0.288 microM/mM packed red blood cell hemoglobin; p<0.05). Ringer lactate, with which the extracorporeal circuit was primed, caused Lact(p) to increase (1.87+/-0.81 vs. 3.27+/-1.15 mM/l; p<0.01). Some lactate entered erythrocytes since Lact(p)/Lact(b) ratio did not change (1.09+/-0.25 vs. 1.07+/-0.23) and some was transformed into pyruvate since Pyr(b) increased [62.9 (30.3-73.3) vs. 100.5 (61.0-146.9) microM/l; p<0.01]. Lact(b)/Pyr(b) ratio did not change significantly [22.6 (16.1-40.5) vs. 27.9 (17.5-35.2)] so that NAD/NADH ratio and, consequently, the rate of glycolysis were unlikely to change too. CONCLUSIONS: Erythrocyte energy metabolism is not affected by CPB, at least during the period of time taken into account in this study.

Adenine Nucleotides↗

[Target controlled infusion (TCI): applications of the "TCI visual" program in anesthesia and sedation with propofol].

BACKGROUND: Systems for Target Controlled Infusion accepting not only patient' data, like Diprifusor, but also a pharmacokinetic model have not been available in Italy in the last years. Therefore a program which controls a Pilot Anesthesia Vial pump and accepts any pharmacokinetic model was developed and applied to propofol infusion for anaesthesia and sedation. METHODS: Two versions of the Visual TCI program have been developed. The first, at intervals, supplies the anaesthetist with the values for the pump; the second directly interacts with the pump. The program also supplies the anaesthetist with the current amount of drug in each compartment and with the estimated awakening time. DESIGN: preliminary prospective study. SETTING: operatory theatre and Intensive Care Unit in a University Hospital. PATIENTS: 6 patients undergoing total intravenous anaesthesia with propofol and fentanyl for abdominal surgery; 6 patients undergoing sedation with propofol in an Intensive Care Unit (the first 4-hour period was taken into account). INTERVENTIONS: propofol infusion was regulated by the Visual TCI program. The first version was employed in three patients of each group and the second one in the others. Hypo- and hypertensive episodes (systolic pressure less than 80 mmHg or higher than basal value plus 25%) were recorded during anaesthesia and sedation. Propofol concentration was measured in plasma three times at defined intervals and per cent differences between measured and computer-calculated values (Predictive error, PE) were calculated. RESULTS: No hypo- or hypertensive episodes were recorded. PE was 27.4 +/- 17.9%. CONCLUSIONS: The program was easily employed, caused no inconvenience, and its use was associated with a remarkable cardiovascular stability. PE distribution was acceptable on the ground of the criteria reported in the literature. The program can be applied to drugs other than propofol, with both two and three compartment pharmacokinetic models and the anaesthetist can choose the most suitable model for the patient.

Adult↗