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A Bufalari

Publications and source records attributed to A Bufalari.

At least 19 recordsLinked to original sources
PubMed2000

Locally advanced rectal cancer: a multivariate analysis of outcome risk factors.

BACKGROUND AND OBJECTIVES: Stages II and III rectal tumors are known as locally advanced rectal cancer (LARC) because they are characterized by a high incidence of local and distant relapses and a low probability of long-term survival. Adjuvant treatments have been advocated to ameliorate overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS) without a univocal beneficial trend. The aim of this study was to identify the independent predictive factors of OS, LRFS, and MFS which could best select patients for adjuvant treatment of LARC. METHODS: Of 153 rectal cancer cases seen consecutively from 1991 to 1998, we studied the main clinical and pathological parameters of 73 LARCs. Clinical and pathological variables were studied by univariate analysis, and independent predictive factors were identified by multivariate analysis. RESULTS: Stages II and III rectal cancer have shown not statistically different rates of OS, LRFS, and MFS. Factors independently associated with increasing OS and MFS were low preoperative carcinoembryonic antigen level (CEA), low number of metastatic lymph nodes, low percentage of metastatic lymph nodes out of the total number of lymph nodes excised, and adjuvant treatment. Increased staging and distal resection margins < or =1 cm were shown to be independent detrimental risk factors regarding OS and MFS, respectively. Independent prognostic factors associated with a reduction in LRFS were advanced age, Hartman's resection, distal resection margins < or =1 cm, and fewer than 14 resected nodes. CONCLUSIONS: Whereas stage I rectal cancer can be treated with a good probability of cure by surgery alone, avoiding adverse effects of adjuvant regimens, the outcome of LARC appears to be positively influenced by adjuvant therapies. In LARC, an accurate study of risk factors would be useful to identify which subset of patients could be favorably influenced by postoperative radiochemotherapy.

Adult↗
PubMed1999

Transplantation of pancreatic islets contained in minimal volume microcapsules in diabetic high mammalians.

To minimize technical problems relating to excessive size (600-800 mu in diameter) of standard alginate microcapsules (CSM) for pancreatic islet graft immunoisolation, we have developed two novel minimal volume, chemically identical, capsule prototypes (MVC): 1) coherent microcapsules (CM), and 2) medium-size microcapsules (300-400 mu, MSM). CM, which envelop each individual islet within a thin alginate hydrogel cast, are prepared by emulsification, whereas MSM are made by atomizing the islet-alginate suspension through a special microdroplet generator. Upon graft into diabetic rodents, CM have shown to immunoprotect both allo- and xenogeneic nondiscordant islets, and restored normoglycemia. In higher mammals, at subtherapeutic doses, CM fully immunoprotected islet allografts (pig-->pig), but only temporarily xenografts (dog-->pig). We then used MSM to immunoisolate canine islet allografts in the peritoneal cavity of dogs with spontaneous insulin-dependent diabetes. Of three grafted dogs, two showed full remission of hyperglycemia with insulin withdrawal. MSM could represent an intermediate solution between CSM and CM for peritoneal immunoisolated islet transplants.

Animals↗
PubMed1999

Propofol anesthesia.

Although questions may still remain regarding the use of this unique sedative-hypnotic drug with anesthetic properties in high-risk patients, our studies have provided cardiopulmonary and neurological evidence of the efficacy and safety of propofol when used as an anesthetic under normal and selected impaired conditions in the dog. 1. Propofol can be safely and effectively used for the induction and maintenance of anesthesia in normal healthy dogs. Propofol is also a reliable and safe anesthetic agent when used during induced cardiovascular and pulmonary-impaired conditions without surgery. The propofol requirements to induce the safe and prompt induction of anesthesia prior to inhalant anesthesia with and without surgery have been determined. 2. The favorable recovery profile associated with propofol offers advantages over traditional anesthetics in clinical situations in which rapid recovery is important. Also, propofol compatibility with a large variety of preanesthetics may increase its use as a safe and reliable i.v. anesthetic for the induction and maintenance of general anesthesia and sedation in small animal veterinary practice. Although propofol has proven to be a valuable adjuvant during short ambulatory procedures, its use for the maintenance of general anesthesia has been questioned for surgery lasting more than 1 hour because of increased cost and marginal differences in recovery times compared with those of standard inhalant or balanced anesthetic techniques. When propofol is used for the maintenance of anesthesia in combination with a sedative/analgesic, the quality of anesthesia is improved as well as the ease with which the practitioner can titrate propofol; therefore, practitioners are able to use i.v. anesthetic techniques more effectively in their clinical practices. 3. Propofol can induce significant depression of respiratory function, characterized by a reduction in the rate of respiration. Potent alpha 2 sedative/analgesics (e.g., xylazine, medetomidine) or opioids (e.g., oxymorphone, butorphanol) increase the probability of respiratory depression during anesthesia. Appropriate consideration of dose reduction and speed of administration of propofol reduces the degree of depression. Cardiovascular changes induced by propofol administration consist of a slight decrease in arterial blood pressures (systolic, mean, diastolic) without a compensatory increase in heart rate. Selective premedicants markedly modify this characteristic response. 4. When coupled with subjective responses to painful stimuli, EEG responses during propofol anesthesia provide clear evidence that satisfactory anesthesia has been achieved in experimental dogs. When propofol is used as the only anesthetic agent, a higher dose is required to induce an equipotent level of CNS depression compared with the situation when dogs are premedicated. 5. The propofol induction dose requirement should be appropriately decreased by 20% to 80% when propofol is administered in combination with sedative or analgesic agents as part of a balanced technique as well as in elderly and debilitated patients. As a general recommendation, the dose of propofol should always be carefully titrated against the needs and responses of the individual patient, as there is considerable variability in anesthetic requirements among patients. Because propofol does not have marked analgesic effects and its metabolism is rapid, the use of local anesthetics, nonsteroidal anti-inflammatory agents, and opioids to provide postoperative analgesia improves the quality of recovery after propofol anesthesia. 6. The cardiovascular depressant effects of propofol are well tolerated in healthy animals, but these effects may be more problematic in high-risk patients with intrinsic cardiac disease as well as in those with systemic disease. In hypovolemic patients and those with limited cardiac reserve, even small induction doses of propofol (0.75-1.5 mg/kg i.v.) can produce profound hypotens

Anesthesia, General↗
PubMed1999

Pancreatic regeneration after subtotal distal resection in rats. Effects of bombesin and octreotide by the in vivo bromodeoxyuridine uptake technique.

Forty male Wistar rats were randomly allocated to four treatment groups after 90% distal pancreatectomy: group A (control) received saline (0.5 ml subcutaneously); group B received bombesin (BBS; 10 microg/kg intraperitoneally); group C received octreotide (2.5 microg/kg subcutaneously), and group D received BBS and octreotide. All substances were injected three times a day until sacrifice after 28 days. BBS increased pancreas weight (p = 0.003) and DNA synthesis (p < 0.001), as measured by a bromodeoxyuridine nuclear-labeling index (BrdU LI). The simultaneous administration of octreotide significantly decreases the remnant pancreas weight (p = 0.016) as compared to group B rats; however the BrdU LI is not significantly reduced in group D as compared to group B. BBS administration promotes regeneration of the remnant pancreas in terms of hypertrophy and hyperplasia. Although octreotide appears to significantly reduce the pancreatic weight increase induced by BBS, it does not reduce DNA synthesis and cell proliferation.

Animals↗
PubMed1999

Hepatoid carcinoma of the stomach: is it still an unusual anatomo-clinical entity? Six cases-report.

Hepatoid carcinoma of the stomach is a rare neoplasm (especially in western countries) characterized by high levels of serum alpha-fetoprotein (AFP), the presence of "hepatoid foci" inside the gastric tumor and poor prognosis, due to the earlier onset of liver metastases. We treated six patients for hepatoid carcinoma of the stomach between 1990 and 1997. The female to male ratio was 1:1, the average age was 71 (54-81) and the average AFP-level was 1160 ng/ml (603-1531). We performed 2 total gastrectomies, 2 subtotal gastrectomies and 2 gastro-jejunostomies (due to presence of liver metastases): in one case, the patient underwent a splenectomy as well. All the tumors showed the presence of "hepatoid foci" (the morphological feature is close to the hepatocellular carcinoma) and a positive immunoreactivity to AFP. The mean survival was 3 months: only one patient is still alive and disease-free (with a 52 months follow-up). After radical surgery, she underwent a chemotherapic treatment with cisplatin, epirubicin, 5-fluorouracil and l-leucovorin. We conclude that our series (the widest in Italy and one of most impressive in Europe) confirm the poor prognosis of this neoplasm, but we also want to underline that this tumor is not so "unusual" any more and it requires new types of treatment, like postoperative chemotherapy, besides surgery, to be fighted properly.

Aged↗
PubMed1998

Bombesin-induced pancreatic regeneration in pigs is mediated by p46Shc/p52Shc and p42/p44 mitogen-activated protein kinase upregulation.

BACKGROUND: In several animal species the pancreas has the capacity to partially regenerate in a self regulating process. A complex network of growth factors modulates this process. There is evidence that bombesin stimulates pancreatic regeneration in rodents. Whether bombesin stimulates pancreas regrowth in large mammals is unknown. Shc proteins, the target of tyrosine kinase-coupled receptors, activate p42 and p44 mitogen-activated protein (MAP) kinase and induce the transcriptional upregulation of genes involved in cell proliferation. The aims of our study were to determine whether bombesin stimulates pancreatic growth in large mammals and whether this event requires Shc-MAP kinase pathway upregulation. METHODS: Three groups of pigs were submitted to sham operation (group 1); to subtotal (70%) distal pancreatectomy (group 2), and to subtotal pancreatectomy followed by bombesin (5 mg three times daily) for 4 weeks (group 3). After a 4-week follow-up a second laparotomy was performed, and the residual pancreas removed. p46Shc, p52Shc and p66Shc, Grb2, and p42/p44 MAP kinase expression and phosphorylation were measured either in freshly isolated pancreatic acinar cells or whole pancreatic extracts. RESULTS: In vivo bombesin administration resulted in: 1) approximately 100% growth of pancreatic duodenal lobe; 2) rapid recovery from exocrine pancreatic failure; and 3) a threefold increase in the rate of pancreatic acinar cell proliferation. Incubating freshly isolated pancreatic acinar cells with bombesin resulted in time- and concentration-dependent stimulation of p46Shc/p52Shc phosphorylation, Shc-Grb2 complex formation, and p42/p44 MAP kinase activation. In vivo bombesin administration significantly upregulated p46Shc/p52Shc and MAP kinase expression and/or activity in whole pancreatic extracts. CONCLUSIONS: In vivo chronic bombesin administration stimulates pancreatic regeneration after pancreatectomy in large mammals. Bombesin-stimulated pancreatic growth is associated with upregulation of the Shc-Grb2-SOS-Ras-MAP kinase pathway.

Adaptor Proteins, Signal Transducing↗
PubMed1997

Evaluation of selected cardiopulmonary and cerebral responses during medetomidine, propofol, and halothane anesthesia for laparoscopy in dogs.

OBJECTIVES: To compare the dose-sparing effect of medetomidine on the propofol induction dose and concentration of halothane for maintenance of anesthesia during laparoscopy and to provide guidelines for effective and safe use of these anesthetics in dogs to ensure desirable perioperative analgesia. ANIMALS: 14 purpose-bred dogs. PROCEDURE: Cardiopulmonary and electroencephalographic responses were determined during 2 anesthesia protocols in dogs scheduled for laparoscopy. Fifteen minutes before anesthesia induction, all dogs received atropine sulfate (0.02 mg/kg of body weight, i.m.). Seven dogs were then given propofol (6.6 mg/kg, i.v.); anesthesia was maintained with halothane in oxygen. The other dogs were given medetomidine hydrochloride (10 micrograms/kg, i.m.) 5 minutes after administration of atropine sulfate; anesthesia was then induced by administration of propofol (2.8 mg/kg, i.v.) and was maintained with halothane in oxygen. RESULTS: The halothane concentration required for laparoscopy was lower in dogs given medetomidine. Anesthetic requirements were significantly increased during abdominal manipulation in both groups. Total amplitude of the electroencephalograph in medetomidine-treated dogs was not significantly lower than that in dogs not given medetomidine. Pulmonary responses were stable throughout all procedures. The primary cardiovascular response was an increase in blood pressure associated with the medetomidine-atropine preanesthetic combination. Significant differences in total amplitude or frequency shifts (spectral edge) of brain wave activity were not associated with surgical stimulation. CONCLUSION: Lack of neurologic changes during laparoscopy supports the efficacy of either medetomidine-propofol-halothane or propofol-halothane combinations at higher concentrations to provide desirable analgesia and anesthesia in this group of dogs.

Adrenergic alpha-Agonists↗
PubMed1996

Surgical care in octogenarians.

The general surgical profile of octogenarians compared with that of younger patients, and risk factors predictive of operative mortality and morbidity, were determined retrospectively using a computer database for all patients admitted between 1989 and 1993. There were 934 admissions of octogenarians and surgery was performed in 447 cases (47.9 percent). The admission rate of patients over 80 years of age increased during the 5-year period from 4.6 to 9.0 per cent, and was significantly higher than that of geriatric patients aged 65-79 years (P < 0.01). Emergency admissions (63.6 percent) and operations (42.3 percent) were more frequent in patients aged over 80 years (P < 0.01); emergency operations increased during the 5 years from 38 to 59 percent. Altogether, 83 deaths and 171 complications were recorded. The mortality rate of octogenarians was greater than that of younger patients (P < 0.01). Postoperative mortality and morbidity rates were 10.1 and 32.2 percent respectively. After multiple logistic regression analysis with stepwise backward elimination, an American Society of Anesthesiologists score of II-V (P < 0.01), the presence of two associated diseases (P < 0.01) and laparotomy procedures (P < 0.03) appeared to be independent risk factors for postoperative mortality and morbidity.

Aged↗
PubMed1996

Effect of octreotide on pancreatic regeneration in rats measured by bromodeoxyuridine uptake.

OBJECTIVE: To study the effects of up to 60 days intermittent octreotide on regeneration of rat pancreas stimulated by cholecystokinin after 70% distal resection. DESIGN. Random controlled experimental study. SETTING: University hospital, Italy. MATERIALS: 60 Male Wistar rats. INTERVENTIONS: Distal resection of splenic and gastric lobes of pancreas (70% of whole gland). Rats were allocated to three groups (n = 20 in each): group A (control) were given saline solution 0.5 ml; group B were given cholecystokinin 300 ng/kg; and group C were given cholecystokinin 300 ng/kg and octreotide 2.5 micrograms/kg. All substances were injected subcutaneously twice a day until death. Four rats were killed weekly for four weeks, and the remainder at 60 days. MAIN OUTCOME MEASURES: Increase in weight of the gland as a percentage of the weight of the whole gland, and DNA synthesis measured by bromodeoxyuridine (BrdU) nuclear labelling index. RESULTS: In the cholecystokinin alone group pancreatic weight had increased significantly on days 21 and 28 (95% confidence intervals (CI) - 13.8 to 12.2 and -44.1 to 19.7, respectively) and the BrdU index had increased significantly at 21 (0.56 to 0.80), 28 (0.26 to 1.3), and 60 (0.09 to 0.51) days compared with the control group. In the group given both cholecystokinin and octreotide the weight was significantly lower than in the cholecystokinin alone group at 21 and 28 days (95% CI - 1.02 to 66.7 and 3.5 to 34.7, respectively) and the BrdU index was significantly lower at 28 days (0.40 to 1.19). CONCLUSIONS: Octreotide seems to reduce the pancreatic regeneration induced by cholecystokinin in rats after 70% distal resection. To our knowledge this has not previously been shown, and the mechanism must be elucidated further.

Animals↗
PubMed1996

Comparative responses to propofol anaesthesia alone and with alpha 2-adrenergic medications in a canine model.

Cardiovascular and pulmonary effects of propofol, a relatively new nonbarbiturate intravenous anaesthetic, were assessed and compared in 22 male and female dogs. Dogs in group 1 did not receive any premedication prior to 6.6 mg/kg IV propofol, group 2 was premedicated with atropine (0.02 mg/kg IM) and the alpha 2-agonist medetomidine (10 micrograms/kg IM), and group 3 received the same premedication agents as group 2, but the medetomidine effects were reversed by the alpha 2-antagonist atipamezole (30 micrograms/kg IV) after 30 min of anaesthesia. Each dog in groups 2 and 3 received a propofol induction dose of 2.2 mg/kg IV. The anaesthetic duration was shortest with propofol alone and prolonged with medetomidine as a premedication which was reversible with atipamezole. In group 1, the most prominent effects were a temporary drop in diastolic arterial blood pressure (26% and 24%) at 2 and 5 min post-propofol, respectively and a drop in respiratory frequency (41%) 2 min after propofol induction. Similar respiratory depression was observed in groups 2 and 3 (20% and 48%, respectively) at the same time. Apnea was not observed. An increase in systemic arterial blood pressure was observed throughout the trial in groups 2 and 3 until dogs recovered or were reversed with atipamezole. Medetomidine significantly reduces propofol dosage requirements. Safe and effective injectable anaesthesia was produced by propofol in this group of dogs. The frequency of respiratory depression would suggest in clinical usage, the practitioner should be aware oxygen supplementation is the treatment of choice should apnea occur.

Adjuvants, Anesthesia↗
PubMed1996

[General surgery in the octogenarian patient. One year's clinical experience].

BACKGROUND: As the number of people over the age of 80 years is rapidly increasing, it may be expected that demand for surgical care for the elderly will also rise during the next decade thus contributing to a change in surgeon attitude. AIM OF THE STUDY: Because little literature is available on the surgical care requested by the over eighties, the aim of this study is to focus on the present surgical demand of the octogenarians in general surgical practice. METHODS: Two hundred-five admissions of 187 patients of above 80 years during one year were recorded retrospectively and statistical evaluation (Fisher exact test or Chi square test) of main clinical features was performed. RESULTS: The rate of surgical admission of octogenarians was 6.5% (205/3135). Half of the patients were admitted as emergencies (52.7%). This percentage was significantly higher (p < 0.000) than in < 80 year old patients (20.8%). The mortality rate for all admissions was 11.2%. In 65.4% of cases a surgical procedure was necessary with a correlated mortality rate of 8.2%. The mortality (2.9%) and morbidity (17%) rate in elective surgery were significantly lower (p = 0.0176 and p = 0.003 respectively) than in emergency surgery (13.6% and 42% respectively). Of all admissions 74.4% were uneventful and, in patients who underwent surgery, complications occurred in 29.8% with no statistically significant differences between patients with or without coexisting disease. The mean hospital stay was 11.4 days and in operated patients was 14.4 days. Almost the total number of patients could be sent home directly. CONCLUSIONS: In octogenarians, surgery is performed more frequently when a complication occurs, but this attitude should be changed because the mortality and morbidity rate are significantly higher. New standards of management and new resources will be requested for the elective surgical care of this rapidly increasing aged group of patients.

Aged↗
PubMed1995

[Gastric cancer in the geriatric patient: our experience].

The Authors report their experience in the management of 68 patients aged over 70 years affected by gastric cancer: 64 of them were operated. After some considerations on patients status, nutritional and immunological conditions, operative risk and cancer characteristics the Authors, on the basis of the results obtained, discuss about the opportunity of surgical therapy and relative adequate surgical techniques in the elderly.

Aged↗