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M Bustamante

Publications and source records attributed to M Bustamante.

At least 19 recordsLinked to original sources
PubMed2006

COL1A1, ESR1, VDR and TGFB1 polymorphisms and haplotypes in relation to BMD in Spanish postmenopausal women.

INTRODUCTION AND HYPOTHESIS: Genetic studies of osteoporosis have focused on analysing single polymorphisms in individual genes - with inconclusive results. An alternative approach may involve haplotypes and gene-gene interactions. The aim of the study was to test the association between the COL1A1, ESR1, VDR and TGFB1 polymorphisms or haplotypes and bone mineral density (BMD) in Spanish postmenopausal women. METHODS: Sixteen polymorphisms were analysed in 719 postmenopausal women. ANOVA, ANCOVA and Xi2 tests were used to perform the statistical analysis. RESULTS: COL1A1 -1997G > T (p=0.04) and TGFB1 Leu10Pro (p=0.02) were found to be associated with adjusted lumbar spine (LS) BMD. Interactions were observed between: the COL1A1 -1997 G/T and Sp1 polymorphisms (p < 0.01 for LS BMD) and the COL1A1 -1663 indelT and VDR ApaI polymorphisms (p < 0.01 for femoral neck (FN) BMD). The COL1A1 GDs and ESR1 LPX haplotypes were associated with FN BMD (p=0.03 and p=0.03). CONCLUSIONS: Polymorphisms at COL1A1 and TGFB1 and haplotypes at COL1A1 and ESR1 were found to be associated with BMD in a cohort of postmenopausal Spanish women. Moreover, COL1A1 polymorphisms showed significant interactions among them and with the VDR 3' polymorphisms.

Bone Density↗
PubMed2005

Doppler ultrasonography for the assessment of tumor necrosis after percutaneous ethanol injection prior to liver transplantation as adjuvant therapy of hepatocellular carcinoma.

INTRODUCTION: Percutaneous ethanol injection (PEI) is considered to be a curative treatment for hepatocellular carcinoma (HCC). The imaging technique of choice for the assessment of local response after PEI has not been well defined, but helical computerized tomography (hCT) has been recommended. The aim of this study was to assess the accuracy of Doppler ultrasonography (US) for evaluation of tumor necrosis after PEI. PATIENTS AND METHODS: Twenty-one patients with single HCC listed for liver transplantation underwent multisession US-guided PEI. Liver Doppler US was done at the 4th week after PEI. Complete response was defined as the absence of any intratumoral Doppler signal. The liver was analyzed in transplant recipients during the follow-up. Complete pathological response was defined as necrosis > or = 90% of total tumor volume. Histological and sonographic findings were compared. RESULTS: Twelve patients underwent transplantation (9 men, mean age 60 +/- 5.2 years). Nine of these (75%) showed a complete ultrasonographic response. In the explanted liver, complete necrosis was present in 6 nodules, and incomplete necrosis was seen in the remaining 6 cases. In comparison with histology, Doppler US showed values of sensitivity, specificity, positive predictive values, and negative predictive values of 50%, 100%, 100%, and 60%, respectively. Overall accuracy was 75%. CONCLUSIONS: In our series, Doppler US showed low sensitivity but high specificity in the assessment of HCC necrosis after PEI. The ultrasonographic finding of complete response requires hCT for confirmation, but the presence in Doppler US of neoplastic viable tissue is enough to indicate a further cycle of PEI.

Administration, Cutaneous↗
PubMed2005

Safety of percutaneous ethanol injection as neoadjuvant therapy for hepatocellular carcinoma in waiting list liver transplant candidates.

UNLABELLED: Orthotopic liver transplantation (OLT) as therapy of hepatocellular carcinoma (HCC) improves the survival of a selected group of patients. Unfortunately, the progressive increase in waiting time for OLT may allow tumor progression. Percutaneous ethanol injection (PEI) has been proposed as neoadjuvant therapy for HCC in patients awaiting OLT, but its safety has not been defined. PATIENTS AND METHODS: During a 60-month period, 34 patients (27 men, overall mean age of 58.5 years, range 41-67) with HCC, were listed for OLT. Ultrasonography-guided PEI was delivered into 39 nodules at 117 sessions on an inpatient basis. Written informed consent was obtained from all patients before PEI. Doppler-ultrasonography was done before PEI, immediately after, and 4 weeks later. Noninvasive monitoring of arterial pressure, cardiac rate, and temperature was performed during the procedure and during a 24-hour period after each session. Pain was considered significant if analgesia was required or discontinuation of PEI necessary. Fever was defined as a temperature > or =37.5 degrees C after PEI. RESULTS: Minor complications included pain in 45 sessions (38.5%), fever in 17 (14.5%), arterial hypertension in 14 (12%), hypotension in 7 (7%), and vomiting in 2 (1.7%). The major complications were segmental liver infarction (n = 3), portal branch venous thrombosis (n = 2), ascites (n = 2), and one case each of subcapsular hematoma, duodenal ulcer, pneumonia, hepatic encephalopathy, and hepatic artery thrombosis. In all cases, clinical outcomes were favorable with conservative treatment. No evidence of tumor seeding in the needle track was reported and no PEI-related mortality observed. CONCLUSIONS: PEI is a safe neoadjuvant therapy for HCC on waiting list liver transplant candidates. In our series, pain and self-limited fever were the most frequent complications. Clinically significant severe complications were uncommon, and nonconservative treatments were not required.

Administration, Cutaneous↗
PubMed2005

Prospective interventional study to evaluate the efficacy and safety of liposomal amphotericin B as prophylaxis of fungal infections in high-risk liver transplant recipients.

INTRODUCTION: Invasive fungal infections are a life-threatening complication in transplant recipients. The prevalence of fungal infection after orthotopic liver transplantation (OLT) is 5% to 42%. The most common isolated pathogens are Candida and Aspergillus species. High-risk liver transplant recipients are more susceptible to the development of invasive fungal infections, with prevalence >40% and mortality rates of 78% to 100%. The strategy for fungal prophylaxis in this population has not been defined. PATIENTS AND METHODS: Among 100 consecutive OLT followed for 28 months, 21 recipients (15 men, overall mean age of 48.5 years, range 23-65 years) were considered to be high risk for the development of fungal infections when they presented at least one of the following criteria: acute liver failure, assisted ventilation >7 days, retransplantation, relaparotomy, antibiotic therapy >14 days, transfusion requirements >20 red blood cells units, and/or biliary leakage. This group received intravenous liposomal amphotericin B (1 mg/kg/d for 7-10 days). RESULTS: One-year survival in the high-risk group was 80%. Prevalence of invasive fungal infection was 9.5%. No Candida infection was observed. Two patients developed Aspergillus infection: an abdominal aspergillosis treated with percutaneous drainage and liposomal amphotericin B (5 mg/kg/d) showed a favorable clinical outcome. The other patient who developed brain aspergillosis died 25 days after OLT. Adverse events related to the drug were hypokalemia (n = 2), back pain (n = 3), and renal dysfunction (n = 2). None of these events required withdrawal of the prophylaxis regimen. CONCLUSION: In our series, prophylaxis with liposomal amphotericin B in high-risk liver graft recipients showed a low rate of severe fungal infections. More studies are needed in order to determine the highest risk population and the best drug dosage.

Amphotericin B↗
PubMed2005

[Revascularization of total renal artery occlusion by angioplasty and stent placement].

Revascularization of renal artery stenosis for the treatment of hypertension is an established procedure. In selected clinical scenarios, successful revascularization procedures may preserve or restore renal function. We present a 66-year-old man with secundary hypertension and deteriorating renal function caused by bilateral atherosclerotic renal artery disease (complete obstruction of the left renal artery and subocclusive stenosis of the right) in which blood pressure was successfully controlled and renal function improved and maintained steady after bilateral percutaneus transluminal angioplasty and renal artery stenting.

Aged↗
PubMed2004

Functional convergence in hydraulic architecture and water relations of tropical savanna trees: from leaf to whole plant.

Functional convergence in hydraulic architecture and water relations, and potential trade-offs in resource allocation were investigated in six dominant neotropical savanna tree species from central Brazil during the peak of the dry season. Common relationships between wood density and several aspects of plant water relations and hydraulic architecture were observed. All species and individuals shared the same negative exponential relationship between sapwood saturated water content and wood density. Wood density was a good predictor of minimum (midday) leaf water potential and total daily transpiration, both of which decreased linearly with increasing wood density for all individuals and species. With respect to hydraulic architecture, specific and leaf-specific hydraulic conductivity decreased and the leaf:sapwood area ratio increased more than 5-fold as wood density increased from 0.37 to 0.71 g cm(-3) for all individuals and species. Wood density was also a good predictor of the temporal dynamics of water flow in stems, with the time of onset of sap flow in the morning and the maximum sap flow tending to occur progressively earlier in the day as wood density increased. Leaf properties associated with wood density included stomatal conductance, specific leaf area, and osmotic potential at the turgor loss point, which decreased linearly with increasing wood density. Wood density increased linearly with decreasing bulk soil water potential experienced by individual plants during the dry season, suggesting that wood density was greatest in individuals with mostly shallow roots, and therefore limited access to more abundant soil water at greater depths. Despite their taxonomic diversity and large intrapopulation differences in architectural traits, the six co-occurring species and their individuals shared similar functional relationships between all pairs of variables studied. Thus, rather than differing intrinsically in physiological responsiveness, the species and the individuals appeared to have distinct operating ranges along common physiological response curves dictated by plant architectural and structural features. The patterns of water uptake and access to soil water during the dry season appeared to be the main determinant of wood density, which constrained evolutionary options related to plant water economy and hydraulic architecture, leading to functional convergence in the neotropical savanna trees studied.

Brazil↗
PubMed2002

Concordance degrees in macrozoobenthic monitoring programmes using different sampling methods and taxonomic resolution levels.

In summer 1997, an intensive survey on the hard bottoms of the 'Abra de Bilbao' (N. Iberian Peninsula) was carried out in the context of the macrozoobenthic monitoring programmes developed to assess the biological recovery of the area. Three types of measurements (abundance, biomass and cover) were used to describe and compare the structure and composition of the communities at three littoral zones: subtidal, lower intertidal and upper intertidal. In addition, several taxonomic aggregation levels of data were successfully applied. The main objective of this paper is to explore the relative effect caused on the results of such programmes by earlier decisions concerning the type of measurement and the taxonomic resolution level to be applied. A 'second stage' multivariate procedure of analysis has been perforrmed based on the previously obtained sampling site ordinations. The measurement type chosen has been found to have a greater effect on the results than the taxonomic resolution used. Moreover, it is suggested that analyses based on abundance data usually lose more information when taxonomic resolution decreases than those based on biomass or cover estimates. The highest concordance among the different analyses has been found in the subtidal zone, which is considered the most appropriate habitat for the development of benthic monitoring programmes.

Biomass↗
PubMed2002

[Development of inflammatory bowel disease in a husband and wife].

It is currently thought that chronic inflammatory bowel disease (IBD) may be due to the action of an as-yet unidentified external agent on genetically predisposed individuals. While genetic influence on the development of the disease has been widely studied, very little is known about the possible environmental agents that could influence its development. One example of the influence of environmental agents could be the development of chronic IBD in a husband and wife. We describe the case of a married couple; after more than 30 years of cohabitation, the wife developed fistulizing Crohn's disease and, 7 years later, the husband developed ulcerative proctosigmoiditis. Currently, approximately 70 cases have been described in the international literature but none have been reported in Spain. We discuss the characteristics of our patients compared with those described in published reports and stress the importance of describing these cases for the future identification of a possible external agent.

Aged↗
PubMed2001

Famciclovir treatment in transplant recipients with HBV-related liver disease: disappointing results.

OBJECTIVE: Long-term administration of hepatitis B immune globulin is effective as prophylaxis for hepatitis B virus (HBV) reinfection but is limited by cost, side effects, availability and a failure rate of 20%. Famciclovir has been shown to be effective in the treatment of hepatitis B in the immunocompetent patient. Fewer data exist in the liver transplant setting, particularly regarding its efficacy in de novo HBV infection. The aims of this pilot study were to determine the effectiveness and safety of long-term administration of famciclovir in recurrent (n = 3) and de novo (n = 3) HBV infection after liver transplantation. METHODS: Six patients with postransplant HBV infection (positivity of serum HBsAg and HBV DNA), four of whom were HBeAg positive, were treated with famciclovir (500 mg, 3 times a day) with a minimum follow-up period of 12 months. Biochemical, serological, virological (HBV DNA by hybridization assays and polymerase chain reaction), and histological (including HBV immunostaining) endpoints were evaluated. RESULTS: None of the patients had a complete biochemical response, with a near complete normalization of ALT levels being observed in 3/6 patients. There was a lack of correlation between virological and biochemical responses. None of the patients seroconverted to anti-HBs or anti-HBe. A virological clearance was observed in only two patients, whereas a moderate reduction in HBV DNA levels was present in one. HBV DNA levels were higher than levels during pretreatment in the three remaining patients. Histological improvement was only observed in one patient. CONCLUSION: Famciclovir alone appears of limited efficacy in the treatment of HBV infection after liver transplantation.

2-Aminopurine↗
PubMed2001

[Autoantibodies against advanced glycation products in patients with type 1 diabetes mellitus].

BACKGROUND: Advanced glycation end products are associated with chronic complications of diabetes mellitus. This glycation process renders many proteins immunogenic. AIM: To detect the presence of antibodies against albumin, collagen and low density lipoprotein glycation products in boys and teenagers with diabetes mellitus. PATIENTS AND METHODS: Thirty one patients with diabetes mellitus type I, aged 11 +/- 3.8 years and with a mean duration of disease of 3.7 +/- 2.7 years and 31 healthy controls aged 12.4 +/- 5.3 years were studied. Antibodies against glycation end products were detected by ELISA and results were expressed as a ratio of the optical density of the glycated protein/optical density of the native protein. RESULTS: Diabetic patients and healthy controls did not have antibodies against albumin glycation end products. Diabetics had higher levels of antibodies than controls for collagen glycation end products (2.6 +/- 0.4 and 1.8 +/- 0.2 respectively, p < 0.01) and low density lipoprotein glycation end products (3.07 +/- 0.92 and 2.2 +/- 0.72 respectively, p < 0.05). CONCLUSIONS: The biological role of these antibodies is not clear. They could be a depuration mechanism for glycation end products or contribute to chronic complications of diabetes mellitus.

Adolescent↗