Biomedical subjects

Fernando Maluenda

Publications and source records attributed to Fernando Maluenda.

12 recordsLinked to original sources

PubMed2007

Polyunsaturated fatty acid pattern in liver and erythrocyte phospholipids from obese patients.

OBJECTIVE: Our aim was to study the fatty acid (FA) composition of liver phospholipids and its relation to that in erythrocyte membranes from patients with obese nonalcoholic fatty liver disease (NAFLD), as an indication of lipid metabolism alterations leading to steatosis. RESEARCH METHODS AND PROCEDURES: Eight control subjects who underwent antireflux surgery and 12 obese patients with NAFLD who underwent subtotal gastrectomy with a gastro-jejunal anastomosis in Roux-en-Y were studied. The oxidative stress status of patients was assessed by serum F2-isoprostanes levels (gas chromatography/negative ion chemical ionization tandem mass spectrometry). Analysis of FA composition of liver and erythrocyte phospholipids was carried out by gas-liquid chromatography. RESULTS: Patients with NAFLD showed serum F2-isoprostanes levels 84% higher than controls. Compared with controls, liver phospholipids from obese patients exhibited significantly 1) lower levels of 20:4n-6, 22:5n-3, 22:6n-3 [docosahexaenoic acid (DHA)], total long-chain polyunsaturated FA (LCPUFA), and total n-3 LCPUFA, 2) higher 22:5n-6 [docosapentaenoic acid (DPAn-6)] levels and n-6/n-3 LCPUFA ratios, and 3) comparable levels of n-6 LCPUFA. Levels of DHA and DPAn-6 in liver were positively correlated with those in erythrocytes (r = 0.77 and r = 0.90, respectively; p < 0.0001), whereas DHA and DPAn-6 showed a negative association in both tissues (r = -0.79, p < 0.0001 and r = -0.58, p < 0.01, respectively), associated with lower DHA/DPAn-6 ratios. DISCUSSION: Obese patients with NAFLD showed marked alterations in the polyunsaturated fatty acid pattern of the liver. These changes are significantly correlated with those found in erythrocytes, thus suggesting that erythrocyte FA composition could be a reliable indicator of derangements in liver lipid metabolism in obese patients.

Adult↗

PubMed2006

Chemoradiotherapy in gallbladder cancer.

Gallbladder cancer (GC) is considered a rare disease associated with a poor prognosis. Unfortunately, the low number of cases makes the performance of trials addressing the role of adjuvant, neoadjuvant, and/or palliative therapy difficult. For a long time, the majority of trials were 5-fluorouracil (5 FU)-based, and results were uniformly poor. Since the introduction of Gemcitabine, response rates of approximately 30% have been observed through the use of this drug and new approaches have been tested. In this sense, drugs such as Cisplatin and Capecitabine have been employed concurrently with gemcitabine and/or radiation. Since a recurrence pattern is both distant and local, chernoradiation seems a logical option to deal with the disease. However, at the present time, the lack of valid and scientific evidence means that most of the recommendations originate from trials dealing with other tumors, such as pancreas cancer and biliary tract cancer (BTC). The aforementioned treatment alternatives warrant further evaluation focusing on GC.

Antimetabolites, Antineoplastic↗

PubMed2006

Increased production of IL-1alpha and TNF-alpha in lipopolysaccharide-stimulated blood from obese patients with non-alcoholic fatty liver disease.

Enhanced pro-inflammatory cytokine production is considered a pathogenic factor in non-alcoholic fatty liver disease (NAFLD). Peripheral blood production of interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) was studied in relation to the severity of histological changes of the liver in obese NAFLD patients. Basal levels in serum and production of IL-1alpha and TNF-alpha in peripheral blood cell cultures after stimulation with lipopolysaccharide (enzyme-linked immunoabsorbent assays) were measured in 11 patients with steatosis and 15 with steatohepatitis, who underwent gastrectomy with a gastro-jejunal anastomosis in roux and Y, and in 9 controls who underwent anti-reflux surgery. Production of IL-1alpha and TNF-alpha was 122 and 67% higher in patients with steatosis than control values, respectively. In patients with steatohepatitis, IL-1alpha production was 300 and 80% higher and that of TNF-alpha 110 and 26% higher, as compared with controls and steatosis patients, respectively. Production of IL-1alpha was positively correlated with that of TNF-alpha (r=0.78, p<0.0001). IL-1alpha and TNF-alpha production were both positively correlated with the degree of steatosis (r=0.68, p<0.001 and r=0.74, p<0.0001) and steatohepatitis (r=0.77 and r=0.75, p<0.0001) at liver biopsy, and with the homeostasis model assessment index (r=0.73, p<0.0001 and r=0.63, p<0.01), respectively. Basal serum IL-1alpha and TNF-alpha levels were comparable in the three groups studied. It is concluded that elevated production of IL-1alpha and TNF-alpha by in vitro stimulated whole blood cell cultures occurs in NAFLD obese patients, which might play a pathophysiological role upon inflammatory leukocyte infiltration of the liver.

Adult↗

PubMed2005

[Strategies for the surgical treatment of gallbladder cancer].

There is controversy in some aspects of the surgical treatment of non-mucosal gallbladder carcinoma. An accurate staging based on T (wall) involvement is crucial, otherwise understanding may yield falsely pessimistic results. The decision about the type of resection to be performed should be based on patient status (age, performance, comorbidities, etc) and tumor characteristics (histological type, vascular, neural or lymphatic spread, cell differentiation, tumor involvement of surgical margins in cystic duct, etc). For muscular (T1b) involvement, there is a great controversy about performing a simple cholecystectomy or en-block radical resection. For T2 there is consensus that an en-block radical surgery including liver resection (IVb - V) and lymphonodal clearance should be performed, since this approach has a great impact in survival. The role of surgical excision for tumors with serosal or liver involvement is controversial, due to the poor survival of these patients. However we have observed a 13% actuarial survival at 5 years, in this subset of patients.

Carcinoma↗

PubMed2005

[Effects of gastric bypass on weight, blood glucose, serum lipid levels and arterial blood pressure in obese patients].

BACKGROUND: Type 2 diabetes, hypertension and serum lipid abnormalities are common among obese people and they should improve with weight reduction. AIM: To study the outcome of these abnormalities after bariatric surgery in morbid obesity patients. MATERIAL AND METHODS: Two hundred thirty two morbid obese patients subjected to gastric bypass, were evaluated in the preoperative period and every three months after surgery, during a minimum of 12 months. Clinical evolution, blood glucose, serum insulin, insulin resistance measured with the homeostasis model assessment (HOMA) and serum lipid levels were analyzed. RESULTS: In the preoperative period, 17% had type 2 diabetes, 49% had abnormal serum lipid levels and 25% had high blood pressure. Sixty six percent had at least one of these abnormalities and 20% had more than one. During follow up, body mass index decreased from 44 to 29.3 kg/m2. Total and HDL cholesterol, blood glucose and insulin resistance significantly decreased from the third month after surgery. Diabetes disappeared in 97% of diabetic subjects, blood pressure normalized in 53% of subjects with hypertension and serum lipid levels returned to normal in 88% of subjects with dyslipidemia. CONCLUSIONS: Gastric bypass in morbid obese patients achieves a significant and important weight reduction that results in significant reductions in the frequency of diabetes, dyslipidemia and hypertension among operated obese subjects.

Adolescent↗

PubMed2005

Results of gastric bypass plus resection of the distal excluded gastric segment in patients with morbid obesity.

Surgical treatment is the procedure of choice for morbidly obese patients. Gastric bypass with a long limb Roux-en-Y anastomosis is the "gold standard" technique for these patients. We sought to determine the early and late results of open gastric bypass with resection of the distal excluded stomach in patients with morbid obesity. We included in this prospective study 400 patients who were seen from September 1999 through August 2003 (311 women and 89 men; mean age, 38.5 years). The mean body mass index of the patients was 46 kg/m2. All underwent 95% distal gastrectomy, with resection of the bypassed stomach, leaving a small gastric pouch of 15 to 20 ml. An end-to-side gastrojejunostomy was performed with circular stapler No. 25. The length of the Roux-en-Y loop was 125 to 150 cm. In all patients, a biopsy was taken from the liver and routine cholecystectomy was performed. Follow-up was as long as 36 months. A barium study was performed in all patients at 5 days after surgery. Mortality and postoperative morbidity rates were 0.5% and 4.75%, respectively, mainly due to anastomotic leak in 10 patients (2.5%). Hospital length of stay was 7 days for 95% of the patients. Follow-up data for longer than 12 months were available in 184 patients. There was excess body weight loss of 70% at 24 and 36 months, and there was an inverse correlation among preoperative body mass index and the loss of weight. Anemia was present in 10%, and incisional hernia was present in 10.2%. At 1 year after surgery, the BAROS index demonstrated very good or excellent index in 96.6% of the patients. Gastric bypass with resection of the distal excluded segment has results very similar to those of gastric bypass alone but eliminates the potential risks of gastric bypass such as anastomotic ulcer, gastrogastric fistula, postoperative bleeding due to peptic ulcer and gastritis, and the eventual future development of gastric cancer. It is also possible to perform via laparoscopy, as we started to do recently.

Adolescent↗

PubMed2005

Conservative management of anastomotic leaks after 557 open gastric bypasses.

BACKGROUND: One of the most serious complications after gastric bypass is an anastomotic leak. In a prospective surgical protocol for the management of this complication, the authors determined the incidence of anastomotic leaks. METHODS: From August 1999 to January 2005, 557 patients with morbid obesity were submitted to laparotomic resectional gastric bypass. In all patients a left drain was placed during surgery. All patients had a radiological study with liquid barium sulphate on the 5th postoperative day. After the occurrence of an anastomotic leak, the daily output of the leak was carefully measured. RESULTS: 12 patients developed an anastomotic leak at the gastrojejunostomy. All were managed medically, with antibiotics if necessary, enteral or parenteral feeding and frequent control by imaging procedures. In 8 patients, the left drain was maintained in situ up to 43 days after surgery. In 4 patients, the drain had been removed between the 5th and 8th days after surgery after a normal radiologic study, but had to be inserted under radiological control 2-3 weeks after the gastric bypass. Daily output increased significantly the second week after surgery, and the leak closed at a mean of 30 days after surgery. One patient of the 12 (8%) died 32 days after surgery from septic shock, without any abdominal collection secondary to the leak. CONCLUSION: The occurrence of an anastomotic leak is nearly 2% after gastric bypass. The majority of them can be managed medically, without the need for a reoperation, due to the fact that there is no acid production in the small gastric pouch and there is no intestinal reflux due to the long Roux loop.

Adolescent↗

PubMed2004

Oxidative stress-related parameters in the liver of non-alcoholic fatty liver disease patients.

Oxidative stress is implicated in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). In the present study, hepatic and plasma oxidative stress-related parameters were measured and correlated with clinical and histological findings in 31 NAFLD patients showing increased body mass index. Liver protein carbonyl content was enhanced by 403% in patients with steatosis (n=15) compared with control values (n=12), whereas glutathione content, superoxide dismutase (SOD) activity and the ferric reducing ability of plasma (FRAP) were decreased by 57%, 48% and 21% (P<0.05) respectively. No changes in microsomal p-nitrophenol hydroxylation and the total content of cytochrome P450 (CYP) or CYP2E1 were observed. Patients with steatohepatitis (n=16) exhibited protein carbonyl content comparable with that of controls, whereas glutathione content, SOD and catalase activities were decreased by 27%, 64% and 48% (P<0.05). In addition, FRAP values in patients with steatohepatitis were reduced by 33% and 15% (P<0.05) when compared with controls and patients with steatosis respectively, whereas p-nitrophenol hydroxylation (52%) and CYP2E1 content (142%) were significantly increased (P<0.05) compared with controls. It is concluded that oxidative stress is developed in the liver of NAFLD patients with steatosis and is exacerbated further in patients with steatohepatitis, which is associated with CYP2E1 induction. Substantial protein oxidation is followed by proteolysis of the modified proteins, which may explain the co-existence of a diminished antioxidant capacity and protein oxidation in the liver of patients with steatohepatitis.

Adolescent↗

PubMed2004

[Laparoscopic splenectomy in hematological diseases].

BACKGROUND: Idiopathic thrombocytopenic purpura (ITP) is the most common indication for elective splenectomy. The laparoscopic approach has been used over the past ten years. AIM: To report our experience with laparoscopic splenectomy. PATIENTS AND METHODS: Retrospective review of 27 patients subjected to splenectomy due to hematological diseases. Among them, 17 patients (78% female, age range 17-70 years old) were subjected to a laparoscopic splenectomy. Eligibility criteria were the presence of benign disease, an informed consent by the patient, a spleen size of less than 20 cm by ultrasound and absence of previous surgery in the upper left quadrant. The rest of the patients were subjected to an open splenectomy. RESULTS: Seventy one percent of patients subjected to laparoscopic splenectomy had an ITP. Mean operating time was 184 minutes. The mean spleen size was 11 cm and the mean weight was 186 g (70-450). No patient died or had complications. No patient required a conversion to an open surgery. Transfusions were not required. The median hospital stay was 3 days. CONCLUSIONS: Elective laparoscopic splenectomy is a safe and low risk surgical procedure.

Adolescent↗

PubMed2002

A prospective randomized study comparing D2 total gastrectomy versus D2 total gastrectomy plus splenectomy in 187 patients with gastric carcinoma.

BACKGROUND: Classic surgical treatment of upper third gastric carcinoma is based on an extended total gastrectomy, including splenectomy. The purpose of this study was to perform a prospective randomized clinical trial comparing the early and late results of total gastrectomy (TG) versus total gastrectomy plus splenectomy (TGS). METHODS: One hundred eighty-seven patients with gastric carcinoma were included. In all patients a D2 total gastrectomy was performed. During surgery they were randomized to 1 of 2 operative options. They were monitored to their death or to 5 years later if they were alive. RESULTS: Operative mortality was similar after both operations (3% after TG and 4% after TGS). Septic complications after surgery were higher after TGS compared with TG (P <.04). Five-year survival rates were not statistically different between groups or in subset analysis according to stage of disease. CONCLUSIONS: On the basis of the results of the present prospective randomized trial, splenectomy is not necessary in early stages of disease. A low operative mortality rate (less than 3%) must be achieved to obtain good long-term results.

Adult↗

PubMed2002

[Obesity: risk factor for steatohepatitis and hepatic fibrosis].

BACKGROUND: Nonalcoholic fatty liver (NAFL) has been recognized as a cause of chronic liver disease. Its main risk factor is obesity. AIM: To describe the clinical and liver pathological findings in a group of patients who underwent surgery as obesity treatment. PATIENTS AND METHODS: Sixty eight patients with severe or morbid obesity were subjected to surgery as obesity treatment. Each patient was evaluated with a complete clinical and laboratory medical assessment. A wedge of liver was excised during surgery. Liver biopsies were analyzed without knowledge of clinical and laboratory findings. The presence of steatosis, inflammation (portal or lobular), fibrosis and cirrhosis were recorded in the pathological analysis. Age and body mass index (BMI) were correlated with pathological data. Significance was set at a p value of less than 0.05. RESULTS: Ninety one percent of patients had steatosis, 45% inflammation and 47% fibrosis. One patient had cirrhosis (1.4%). There was a statistically significant association between BMI and moderate or severe steatosis (p < 0.03). There was also an association between BMI and portal (p = 0.017) and lobular inflammation (p = 0.034). A BMI over 40 kg/m2 (morbid obesity) was significantly associated with the presence of fibrosis (p = 0.032). Moreover, the presence of moderate or severe steatosis was a risk factor for the development of hepatic fibrosis (p = 0.026). CONCLUSIONS: Obesity is a major and independent risk factor for steatohepatitis and fibrosis. The degree of steatosis in the liver biopsy, is a risk factor for the development of fibrosis.

Adolescent↗

PubMed2002

[Early enteral nutrition in cancer patients subjected to a total gastrectomy].

BACKGROUND: Total parenteral nutrition has a high cost and frequency of complications. Enteral feeding is a feasible alternative that can be started early in the postoperative period. AIM: To assess digestive tolerance to early enteral feeding in cancer patients undergoing total gastrectomy and to compare early enteral feeding (EEF) with total parenteral nutrition plus enteral feeding (TPN + EF), initiated after overcoming postoperative ileus. PATIENTS AND METHODS: Subjects with a resectable gastric cancer were considered eligible for the study. During surgery a nasoenteral tube was placed and patients were prospectively randomized to EEF or TPN + EF. Digestive tolerance, effectiveness, complications and costs between both modalities of nutritional support were compared. RESULTS: Twenty eight patients (15 male, aged 63 +/- 14 years old) were studied. Fourteen patients were randomized to EEF and 14 to TPN + EF. Diarrhea occurred in 14 and 29% of EEF and TPN + EF patients respectively, (p: NS). Patients with TPN + EF received an average of 28 Cal/kg/day and 1.1 g/kg/day proteins. Patients with EEF received an average of 29 Cal/kg/day and 0.8 g/kg/day proteins. At the eighth postoperative day, serum albumin was 3.9 +/- 0.7 and 3.2 +/- 0.5 g/dl in EEF and TPN + EF patients respectively (p < 0.05), serum prealbumin was 16.9 +/- 5 and 12.3 +/- 4.3 mg/dl in EEF and TPN + EF patients respectively (p < 0.05) and nitrogen balance was +2.4 +/- 1.5 and -1.6 +/- 0.6 g/24 h in EEF and TPN + EF patients respectively (p < 0.05). Postoperative hyperglycemia was observed with a lower frequency and nutritional support costs and length of hospital stay were significantly lower in the EEF group. CONCLUSIONS: After total gastrectomy EEF is well tolerated, safe and effective, even during the early postoperative ileus. This therapeutic modality could be the first choice for nutritional support in these patients.

Aged↗