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J L Balibrea

Publications and source records attributed to J L Balibrea.

At least 55 records · Page 3Linked to original sources
PubMed1996

NO2/NO3 and cytokine plasma profiles under different postoperative parenteral nutrition regimens.

Both nitric oxide and cytokines are considered mediators of the acute-phase response in humans, and their early postoperative period plasma levels have been found to be of prognostic value. On the other hand, it has been suggested that the fatty emulsions used in total parenteral nutrition (TPN) may induce changes in macrophage function. In the present study we investigated the postoperative evolution of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), interleukin-6 (IL-6), and nitrate/nitrite plasma levels under three different TPN regimens. Twenty-one patients diagnosed with upper digestive tract neoplasm, without preoperative TPN, and having undergone radical surgery, were randomly assigned to three groups: Group I, all nonprotein calories supplied by hypertonic glucose solution: Group II, 55% of the nonprotein calories supplied by glucose and 45% by 20% long-chain triacylglycerides emulsion (LCT) (Intralipid 20%, Kabi-Pharmacia); Group III, same as Group II, but a 20% emulsion of a mixture of medium-chain and long-chain triacylglycerides (MCT/LCT) (Lipofundina MCT/LCT 20%, B. Braun) was used instead of LCT. Blood samples were obtained on postoperative Days 1-5 and 10, 3 h after ending the lipid infusion. In all the three groups IL-1, IL-6, and TNF-alpha levels rose after surgery, peaking at Day 2, whereas NO2/NO3 levels had their peak at Day 3. Day-to-day comparison of plasma levels of cytokines and NO2/NO3 between the investigated groups did not show any statistical significance. Differences between group means were not found when the areas under the curve over the first 5 postoperative days were compared (1.72 +/- 0.25, Group I; 1.88 +/- 0.34, Group II; and 2.52 +/- 0.50, Group III, for TNF-alpha; 1.79 +/- 0.12, Group I; 1.92 +/- 0.18, Group II; and 1.50 +/- 0.12, Group III, for NO2/NO3). We conclude that the different parenteral nutrition regimens studied do not evoke alterations in cytokine and NO2 + NO3 levels in the patient groups investigated in this study.

Cytokines↗
PubMed1996

Prediction of survival and recurrence by serum and cytosolic levels of CEA, CA125 and SCC antigens in resectable non-small-cell lung cancer.

Risk of death and risk of recurrence in 108 potentially curable non-small-cell lung cancer patients were analysed with respect of TNM stage, histological type and carcinoembryonic antigen (CEA), CA125 antigen and squamous cell carcinoma antigen (SCC) levels in serum and cytosol. CA125 and CEA levels were closely related to outcome figures. Multivariate analyses indicated that TNM stage and histological type had the best predictive power, but serum and cytosolic CA125 and serum CEA contained additional, independent prognostic information. Predictive information drawn from serum and cytosolic levels proved mutually complementary. We conclude that CA125 and CEA complement TNM classification and histological type for the purpose of quantifying risk of death or recurrence.

Adenocarcinoma↗
PubMed1996

Influence of cryopreservation on the sensitivity of human islets to tumor necrosis factor.

Tumor necrosis factor (TNF alpha) has been shown to inhibit insulin release and it has been postulated to-be an important effector in islet rejection. We studied the effect of cryopreservation on glucose oxidation rate (GOR), lipid synthesis, hormone secretion (insulin, glucagon, somatostatin, thyrotropin-releasing hormone), and cyclic guanosine 3',5'-monophosphate (cGMP) content of human islets, in the presence or absence of TNF alpha, looking for changes that could explain a different susceptibility to rejection for cryopreserved islets. Islets were isolated from multiple organ donor pancreata by collagenase digestion. The islets were then cultured for 7 days, cryopreserved (-0.25 degrees C/min), and stored in liquid N2. After 24 h of culture, thawed islets were cultured for an other 24 h in the presence or absence of TNF alpha. Islets were then washed to remove the cytokine and incubated in Krebs-Ringer bicarbonate (5 or 20 mM glucose), and both the cGMP content of the islets and the hormone concentration in the medium were determined by radio-immunoassay. GOR was measured as the production of 14CO2 from 5 or 20 mM D-[U-14C]glucose, and de novo lipid synthesis was determined as D-[U-14C]glucose incorporation into different lipidic fractions. Cryopreservation did not significantly modify the hormone response to glucose but it partially reversed the TNF alpha-induced inhibitory effect on insulin release in the presence of 20 mM glucose. In addition, the inhibitory effect of TNF alpha on phosphatidylcholine labeling was attenuated in cryopreserved islets compared with noncryopreserved islets. TNF alpha significantly stimulated islet nitrite production and cGMP accumulation, both effects being of a similar magnitude in cryopreserved and noncryopreserved islets. Our results suggest that cryopreservation can modify the metabolic and hormone response of human islets to TNF alpha. This effect is not mediated by changes in the TNF alpha-induced islet nitric oxide production or cGMP accumulation.

Adolescent↗
PubMed1996

TNF-alpha-induced inhibition of PC synthesis by human type II pneumocytes is sequentially mediated by PGE2 and NO.

Tumor necrosis factor-alpha (TNF-alpha)-induced inhibition of surfactant synthesis participates in the pathogenesis of the acute respiratory distress syndrome. We examined the ability of human type II pneumocytes to produce nitric oxide (NO) in the presence of TNF-alpha as well as the role of NO and prostaglandin (PG) E2 in the transduction of the cytokine signal. Multiple organ donors were used as a source of lung tissue. After 24-h preculture, type II pneumocytes were cultured for 18 h in the presence or absence of additives. The D-[U-14C] glucose incorporation into phosphatidylcholine (PC) was selectively inhibited by TNF-alpha, PGE2, sodium nitroprusside (SNP), or 8-bromoguanosine 3',5'-cyclic monophosphate. The effect of TNF-alpha was attenuated by indomethacin, N omega-nitro-L-arginine methyl ester (NAME), or methylene blue (MB). The effect of PGE2 was attenuated by NAME, while that of SNP was reversed by MB but not by indomethacin. TNF-alpha induced an increase in PGE2 and guanosine 3',5'-cyclic monophosphate cell content and in the NO release to the medium. NAME did not affect PGE2 production, while indomethacin blunted NO generation. Our results suggest that NO generation, secondary to PGE2 production, is responsible for the TNF-alpha-induced inhibition of PC synthesis by human type II pneumocytes.

Cells, Cultured↗
PubMed1996

[Colorectal cancer: has its diagnosis improved in the last decade?].

OBJECTIVE: To assess whether any shift in pathologic stage, tumor resectability and need of emergency surgery has been observed in colorectal carcinoma patients over the last ten years. EXPERIMENTAL DESIGN: Retrospective study. PATIENTS: We compare 201 patients treated in our Service from January 1981 to December 1983 (Group I) with 306 patients operated from January 1991 to December 1993 (Group II). RESULTS: No change has been noticed in any of the parameters analyzed. CONCLUSIONS: We think that the efforts in earlier detection of CCR should be increased to improve the prognosis of the disease.

Age Factors↗
PubMed1996

[Colorectal metachronous tumors].

INTRODUCTION: The metachronous colorectal carcinoma is defined as a primary carcinoma which arises after surgical removal of a previous carcinoma of the large bowel. The incidence of metachronous colorectal cancer has been reported to be 1-8 per cent. THE AIM: The purpose of the present study was to determine the incidence of metachronous colorectal carcinoma and, on this basis, to propose a follow-up programme after primary resection for cure in this patient group of patients. PATIENTS AND METHODS: Twenty-eight patients with metachronous colorectal malignancies underwent surgery, 16 (57.1%) male and 12 (42.9%) female. These metachronous cancers were discovered at intervals ranging from eight months to seven years (range 28 +/- 10 months). Nine (32%) metachronous lesions were detected two years of more after the original cancer. Six of the metachronous cancers appeared in the right colon, eight were distributed throughout the transverse and descending colon, and fourteen in the rectosigmoid region. Histological examination revealed a high proportion of early stage lesions (82.1% Duke's A more B). CONCLUSION: A set of patients surviving their initial colorectal cancer should be followed for the rest of their life because of the risk of developing a second primary. In the light of our experience, a full examination of the colon in these patients is mandatory, and colonoscopy is the best diagnostic procedure.

Adult↗
PubMed1995

Both prostaglandin E2 and nitric oxide sequentially mediate the tumor necrosis factor alpha-induced inhibition of surfactant synthesis by human type II pneumocytes.

BACKGROUND: Tumor necrosis factor alpha (TNF-alpha)-induced inhibition of surfactant synthesis seems to participate in the pathogenesis of the adult respiratory distress syndrome. OBJECTIVES: To examine the ability of human type II pneumocytes to produce nitric oxide (NO) in the presence of TNF-alpha and, in addition, to explore the role of this radical in the transduction of the cytokine signal. DESIGN: Multiple organ donors were the source of lung tissue specimens. Type II pneumocytes were isolated by enzymatic digestion, adherence separation of macrophages, and gradient purification. After 24-hour preculture, cells were cultured for 24 hours in the presence or absence of TNF-alpha (100 ng/mL), sodium nitroprusside (100 mumol/L), N omega-nitro-L-arginine methyl ester (NAME) (1 mmol/L), methylene blue (10 mumol/L),8-bromo-3',5'-cyclic guanosine monophosphate (8-Br-cGMP) (1 mmol/L), prostaglandin E2 (PGE2) (0.1 mumol/L), indomethacin (30 mumol/L), and combinations. The NO release to the medium and cGMP and PGE2 contents of the cells were measured. RESULTS: The incorporation of 14C-labeled glucose (D-[U-14C]glucose) into phosphatidylcholine and phosphatidylglycerol was selectively inhibited either by 8-Br-cGMP or in the presence of TNF-alpha, PGE2, or nitroprusside, all of which caused an increase in the intracellular levels of cGMP. The inhibitory effect of TNF-alpha was partially reverted by indomethacin, NAME, N-monomethyl arginine, or methylene blue. The inhibitory effect of PGE2 was partially reverted by NAME, while that of nitroprusside was reverted by methylene blue, but not by indomethacin. Tumor necrosis factor alpha induced an increase in PGE2 (4.31 +/- 0.27 vs 1.65 +/- 0.17-pg/microgram protein, n = 10, P < .01) and cGMP (0.238 +/- 0.012 vs 0.109 +/- 0.014-pmol/microgram protein, n = 10, P < .01) cell content and in the NO release to the medium (3.10 +/- 0.14 vs 1.19 +/- 0.11-nmol/microgram protein, n = 10, P < .01). The basal NO release to the medium was also increased in the presence of PGE2. The NAME, which blocked NO generation and cGMP increase, did not affect PGE2 production in response to TNF-alpha. However, indomethacin, which blocked PGE2 production, also blunted NO generation and cGMP increase. CONCLUSIONS: The NO generation, secondary to PGE2 production, seems responsible for the TNF-alpha-induced inhibition of phosphatidylcholine synthesis by human type II pneumocytes. Nitric oxide seems to exert this effect through activation of guanylyl cyclase.

Adolescent↗
PubMed1995

Evidence for a cyclic guanosine monophosphate-dependent, carbon monoxide-mediated, signaling system in the regulation of TNF-alpha production by human pulmonary macrophages.

BACKGROUND AND OBJECTIVES: The second messenger cyclic guanosine 3',5'-monophosphate (cGMP) seems to be implicated in the release of tumor necrosis factor alpha (TNF-alpha) by activated macrophages. There is controversy regarding the potential of human macrophages to produce nitric oxide (NO). Since guanylate cyclase can be activated also by carbon monoxide (CO) and this gas may be formed endogenously, we examined the ability of human pulmonary macrophages to produce CO in the presence of lipopolysaccharide (LPS) or LPS+interferon gamma (IFN-gamma). In addition, the source and the relative contribution of this molecule to the LPS-induced increase in cell cGMP content and TNF-alpha release were explored. DESIGN: Interstitial macrophages were obtained from multiple organ donor lungs by enzymatic digestion. After 24-hour preculture, purified macrophages were cultured for 24 hours in the presence or absence of LPS, LPS+IFN-gamma, CO (250 and 500 mumol/L), sodium nitroprusside, 8-Br-cGMP, hemoglobin, methylene blue, zinc-protoporphyrin IX, hemin, S-adenosylmethionine, deferoxamine mesylate, or combinations. The cGMP content of the cells and TNF-alpha, CO, and NO release to the medium were determined. RESULTS: In the presence of LPS, TNF-alpha production was not accompanied by any detectable increase in the NO release to the medium. However, an increase in medium CO concentration (mean +/- SEM) (5.81 +/- 0.20 vs 3.74 +/- 0.08 pmol/microgram protein; n = 11; P < .01) and cell cGMP content (0.273 +/- 0.021 vs 0.138 +/- 0.019 pmol/microgram protein; n = 10; P < .01) was observed. These changes were more pronounced in the presence of LPS+IFN-gamma. Release of TNF-alpha also was induced by both sodium nitroprusside and 8-Br-cGMP. In contrast, methylene blue, a guanylate cyclase inhibitor, inhibited LPS-, LPS+IFN-gamma-, and sodium nitroprusside-induced TNF-alpha production and cGMP increase; hemoglobin, which traps CO, had a similar effect. CONCLUSION: Intracellular cGMP increase, secondary to an endogenous production of CO, participates in the release of TNF-alpha by activated human pulmonary macrophages.

Adolescent↗
PubMed1995

Beneficial effect of S-adenosylmethionine during both cold storage and cryopreservation of isolated hepatocytes.

Oxygen free radicals appear to be the prime cell-toxic products during cold preservation. Glutathione (GSH) seems to play a critical role in cell protection against oxidant stress. The experimental decrease of intracellular GSH in vivo may be prevented by the administration of S-adenosylmethionine (SAMe), which seems also to play an important role in preserving the structure of cell membranes. We designed our study to investigate whether the addition of SAMe to EuroCollins solution (EC) could provide a similar degree of protection as the more complex University of Wisconsin (UW) solution during cold preservation. In addition, we have investigated a possible protective action of SAMe during hepatocyte cryopreservation. Wistar rat hepatocytes (10(6) cells/ml) were stored in either EC (+/- 12 mumol/l SAMe) or UW. In parallel, hepatocytes (10(6) cells/ml) were cryopreserved in M199 culture medium (+/- SAMe) using dimethyl sulfoxide as cryoprotectant. LDH release, viability, and hepatocyte GSH and malondialdehyde (MDA) content were sequentially determined during cold preservation. There were no differences on viability or GSH and MDA content between EC+SAMe and UW stored cells, although LDH release was slightly higher in the first group. The addition of SAMe also attenuated the decrease in both viability (37 +/- 0.8 vs 53.0 +/- 7.4%, mean +/- SEM, N = 5, P < 0.05) and GSH content (13.4 +/- 15.1 vs 45.1 +/- 16.8%, mean +/- SEM, N = 5, P < 0.01), observed after thawing. Our results suggest that SAMe could be a useful additive for both cold storage and cryopreservation solutions of hepatocytes.

Animals↗
PubMed1995

Somatostatin reduces the levels of tumor necrosis factor alpha in a rat model of endotoxemia induced by lipopolysaccharide.

The role of tumor necrosis factor alpha (TNF) in the toxic and lethal effects of the endotoxemia associated with septic shock is well known. This study was designed to establish whether natural somatostatin (SS-14) is capable of modifying the production of TNF in a model of septic shock induced in the rat by bacterial lipopolysaccharide (LPS), and its theoretical relationship to prostaglandin E2 (PGE2). An experimental study was carried out in 80 Wistar rats subjected to intravenous LPS injection. Perfusion of SS-14 at 2 micrograms/h or continuous isotonic saline (IS) at 0.1 ml/h started 30 min prior to LPS injection and continued until 90 min after. All the animals were primed 15 days earlier with on intraperitoneal dose of BCG (2.2 x 10(7) CFU). ELISA assays were used to measure TNF levels after 90 min of perfusion and those of PGE2 at 30 and 90 min. The effects of two different doses of LPS (0.5 mg/kg of body weight and 5 mg/kg bw) were compared. SS-14 administration was associated with a decrease in TNF levels (1130.0 +/- 272.4 vs 4720.0 +/- 1278.1 pg/ml, P = 0.013), and an increase in serum PGE2 basally (255.7 +/- 94.2 vs 62.0 +/- 10.6 pg/ml, P = 0.04) and after 90 min of perfusion (1872.7 +/- 1250.6 vs 1009.7 +/- 612.0 pg/ml, P = NS), there being a statistically significant correlation between the basal PGE2 levels and these TNF after 90 min when compared using a regression model (r = -0.88, P = 0.04 for the 0.5 mg/kg dose; r = -0.47, P = 0.07 for 5 mg/kg). At 90 min, the level of TNF also depended on the PGE2 values (r = 0.84, P = 0.07 for 0.5 mg/kg; r = 0.55, P = 0.03 for 5 mg/kg). Multiple regression permitted TNF levels to be estimated on the basis of basal and 90 min PGE2 levels (P = 0.03). Pretreatment with SS-14 led to a significant reduction of TNF and an increase of PGE2, there being an apparent correlation between the two.

Animals↗
PubMed1995

[Surgical treatment of pulmonary aspergilloma].

Pulmonary aspergilloma can now be classified as an opportunistic disease given that Aspergillus tends to colonize preexisting cavities in the lung. Aspergilloma is the usual pleuropulmonary anatomical sign, hemoptysis is the most frequent symptom and a chest film is the simplest diagnostic tool. The advisability of surgery is disputed, particularly in asymptomatic patients and/or those at high surgical risk. We describe 14 patients who underwent surgery in our department, evaluating aspects of their clinical signs, diagnosis, attitude toward treatment and the course of their disease. We believe that for patients with symptomatic pulmonary aspergilloma, the treatment of choice is surgery, preferably lung resection. All patients who do not present contraindications for general surgery can be considered operable.

Adult↗
PubMed1995

[Treatment with sulindac of adenomatous polyps in familial polyposis].

BACKGROUND: The effect of sulindac, a nonsteroid antiinflammatory drug, has been reported to cause both regression and suppression of colon polyps in patients with familial adenomatous polyposis and Gardner's syndrome. We report our experience with seven patients with diffuse colonic polyposis treated with sulindac. PATIENTS AND METHODS: Seven patients with familiar adenomatous polyposis, four men and three women (mean age, 30 years; range 16 to 41 years) were included in this study. Two patients that underwent prior colectoctomy with ileorectal anastomosis and had polyps in the rectum were also included. The polyps ranged in size from 0.2 to 2.5 cm; most of them were less than 1 cm. Sulindac was given 150 mg. twice a day. Further colonoscopic examination was done at 6-month intervals during follow-up in all patients. RESULTS: A disappearance or a marked reduction in the number and size of polyps was observed in all patients after 24 months of treatment with sulindac. The drug was well tolerated and no side effects were observed during treatment. CONCLUSION: The authors conclude that sulindac is effective in inducing the regression of rectal polyps in familial, adenomatous polyposis.

Adenomatous Polyposis Coli↗
PubMed1995

[The prognostic value of common predictive variables in rectal cancer].

BACKGROUND: A study was undertaken to identify common clinical variables, easy to obtain in an out-patient office, that complement the prognostic estimation on survival offered by the staging classification in patients operated on for rectal cancer. PATIENTS AND METHODS: 236 patients were included. Twenty-one variables related to symptoms, examinations, type of operation, tumor stage, pathology and follow-up were evaluated, all of them were collected prospectively. The relative predictive value was analyzed by means of the Cox' proportional hazards progression model. RESULTS: Age, carcinoembryonic antigen (CEA), alcaline fosfatase (FA), deshidrogenase lactate (LDH), elective surgery, showed independent predictive value. The risk of death raised by 1.026 (CI 95%: 1.005-1.047) for each year of age at the moment of surgery, serum CEA over 5 ng/ml raises the risk by 2.32 (IC 95%: 1.385-3.893), LDH over 190 mU/ml by raises the risk by 1.64 (IC 95%: 1.026-2.639), FA over 250 U/ml raises the risk by 2.16 (IC 95%: 1.027-4.578), elective surgery reduces the risk by 0.32 (IC 95%: 0.106-0.965). CONCLUSIONS: Age, CEA, LDH, FA and elective surgery, complement the prediction on survival offered by the tumor stage in patients operated on for rectal cancer.

Chi-Square Distribution↗
PubMed1995

[Appendiceal Crohn's disease].

Crohn's disease of the appendix is an uncommon process that is more frequent in young people. The most common preoperative diagnosis is acute appendicitis. At exploratory laparotomy the appendix is enlarged and malignancy may be suspected. The differential diagnosis may be difficult. Serologic tests and cultures should be performed to exclude Yersinia infections. Appendicectomy is a safe procedure when the disease is limited to the appendix. The postoperative course is usually uncomplicated with a low rate of complications and recurrence. Although it may be a different process than Crohn's disease and the recurrence rate is low, it is suggested that all the patients should be followed-up so that recurrences may be recognized and treated as early as possible. A new case is presented after two years of follow-up without recurrence.

Abscess↗