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1.
Dig Dis Sci ; 62(3): 755-760, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28025744

RESUMEN

BACKGROUND: Syndecan-1 (SDC1) is essential for maintaining normal epithelial barrier. Shedding of SDC1 ectodomain, reflected by serum soluble syndecan-1 (SSDC1) levels, is regulated by inflammation. Increased intestinal permeability plays a central role in celiac disease (CD). The association between SSDC1 levels and mucosal damage in CD has not been evaluated. AIMS: To evaluate serum SSDC1 levels in children with CD and to determine its relationship with histological grading classified by modified Marsh criteria. METHODS: This is a cross-sectional, pilot study, in which serum SSDC1 was analyzed by ELISA in a cohort of 49 untreated children with CD and 15 children with nonspecific abdominal pain (AP). CD was diagnosed based on positive celiac serology and small intestinal biopsy. SSDC1 levels at the time of biopsy were correlated with Marsh grading. Controls were defined by AP, negative celiac serology, normal upper endoscopy, and small intestinal biopsies. RESULTS: SSDC1 levels were significantly higher in CD patients compared to AP controls (116.2 ± 161 vs. 41.3 ± 17.5 ng/ml, respectively, p < 0.01). SSDC1 levels were significantly higher in patients with Marsh 3c lesion compared to AP controls (170.6 ± 201 vs. 41.3 ± 17.5 ng/ml, respectively, p < 0.05). SSDC1 concentrations displayed a significant correlation with mucosal damage defined by Marsh (r = 0.39, p < 0.05). CONCLUSION: This is the first study demonstrating elevated levels of serum SSDC1 in children with CD. Our results suggest that SSDC1 is a potentially novel marker of intestinal mucosal damage in patients with CD. Its applicability as a surrogate biomarker in CD remains to be determined.


Asunto(s)
Mucosa Intestinal/patología , Intestino Delgado/patología , Sindecano-1/sangre , Adolescente , Biomarcadores/sangre , Biopsia/métodos , Enfermedad Celíaca/sangre , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/patología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Israel , Masculino , Proyectos Piloto , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Estadística como Asunto
2.
Dis Esophagus ; 22(7): 611-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19302217

RESUMEN

The clinical significance of nonspecific esophageal motility disorder (NEMD) is unclear. Our aim was to investigate the natural history of NEMD. All manometries performed at Meir Hospital from 1997 to 2004 and diagnosed as NEMD were reviewed. Manometric criteria for NEMD included either low-amplitude peristalsis, nonprogression of peristalsis, prolonged retrograde or triple-peaked waves, or incomplete relaxation of the lower sphincter. Patients determined to have NEMD were contacted and asked to complete a questionnaire and undergo a second manometry. NEMD had been diagnosed in 137 patients. Upon review of manometry results, 65 patients were eligible for the study (36 men and 29 women). The other 72 patients did not have NEMD when we reviewed their manometry tracing, applying strict criteria as specified in Table 1. The average age was 64 +/- 16 years (range 24-83 years). The average follow-up period was 7 +/- 2 years. All 65 patients were symptomatic at their initial prestudy visit. By the second visit, symptoms had resolved in 33 (51%) patients and improved in 13 (19%). Dysphagia, chest pain, and food regurgitation had improved, whereas heartburn and respiratory symptoms had not. Of 37 patients with triple-peaked waves, only 11 (30%) had improved clinically. Of the 65 study patients, 17 (26%) had a second manometry during the study, which was normal in 2 (12%), unchanged in 11 (69%), and revealed achalasia in 4 (23%), representing 6% of all study patients. NEMD is generally a benign disorder that improves clinically in most cases. Nevertheless, in about 6% of patients, NEMD may evolve into achalasia.


Asunto(s)
Trastornos de la Motilidad Esofágica/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Acalasia del Esófago/diagnóstico , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Peristaltismo , Estudios Retrospectivos , Adulto Joven
3.
Surg Endosc ; 22(9): 1971-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18214607

RESUMEN

BACKGROUND: As suggested by observational and animal studies, heparin has antiinflammatory effects that could prevent acute post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. Low-molecular-weight heparin did not reduce the incidence of post-ERCP pancreatitis in a controlled study. The current study aimed to determine whether prophylactic administration of low-dose unfractionated heparin, which has potentially more antiinflammatory capability, can prevent acute post-ERCP pancreatitis. METHODS: Patients scheduled for ERCP in the authors' department were randomized to receive unfractionated heparin (5,000 IU) or placebo (saline solution 0.5 ml) administered subcutaneously 20 to 30 min before the ERCP. Patients who had undergone endoscopic sphincterotomy in the past were excluded from the study. Post-ERCP pancreatitis was defined according to criteria established by Cotton: abdominal pain combined with a threefold elevation of blood amylase 24 h after the ERCP. RESULTS: The study enrolled 106 patients. One patient was excluded from the analysis due to inaccessible papilla of Vater, leaving 51 patients in the heparin group and 54 in the placebo group, for a total of 105 patients (62 women and 43 men) with a mean age of 64.6 years. The rate of post-ERCP pancreatitis was not different between the groups (heparin, 4 patients, 7.8%; placebo, 4 patients, 7.4%). Two patients in each group experienced mild bleeding. CONCLUSIONS: The study did not demonstrate a significant effect of low-dose unfractionated heparin in the prevention of post-ERCP pancreatitis. A multicenter trial with a larger number of patients is needed to demonstrate a benefit from this drug.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Heparina/uso terapéutico , Pancreatitis/prevención & control , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Amilasas/sangre , Antiinflamatorios no Esteroideos/administración & dosificación , Femenino , Heparina/administración & dosificación , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Insuficiencia del Tratamiento
4.
J Clin Invest ; 90(3): 1155-60, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1522223

RESUMEN

Precipitation of cholesterol in gallbladder bile is believed to produce platelike cholesterol monohydrate crystals directly. We report complementary time-lapse microscopic studies of cholesterol crystallization from model bile that reveal initial assembly of filamentous cholesterol crystals covered by a monomolecular layer of lecithin. Over a few days, the filaments evolved through needle, helical, and tubular microstructures to form classical platelike cholesterol monohydrate crystals. Similar crystallization phenomena were observed in human gallbladder biles from cholesterol but not pigment stone patients. Synchrotron x-ray diffraction of the earliest filaments suggested a cholesterol monohydrate polymorph or admixture with an anhydrous cholesterol precursor. However, density gradient centrifugation of filamentous crystals revealed that their density was 1.032 g/ml, consistent with anhydrous cholesterol. Conventional x-ray diffraction of transitional crystalline forms was consistent with pure cholesterol monohydrate crystals, as were the equilibrium platelike crystals. These novel findings suggest that crystalline cholesterol in bile may not be completely mature or hydrated initially, but undergoes a series of transformations to become thermodynamically stable monohydrate plates. These observations have important implications for understanding the control of cholesterol crystallization in bile, as well as explaining putative crystal cytotoxicity during gallstone formation.


Asunto(s)
Bilis/química , Colesterol/química , Cristalización , Humanos , Microscopía , Difracción de Rayos X
5.
Surg Endosc ; 21(5): 769-73, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17342562

RESUMEN

BACKGROUND: Some patients with suspected common bile duct (CBD) stones are found to have sludge and no stones. Although sludge in the gallbladder is a precursor of gallbladder stones, the significance of bile duct sludge (BDS) is poorly defined. This study aimed to compare BDS with bile duct stones in terms of frequency, associated risk factors, and clinical outcome after endoscopic therapy. METHODS: The study enrolled 228 patients who underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) for suspected choledocholithiasis. The patients were divided into two groups: patients with BDS but no stones on ERCP and patients with CBD stones. The presence of risk factors for bile duct stones (age, periampullary diverticulum, ductal dilation or angulation, previous open cholecystectomy) were assessed at ERCP. Follow-up data (36 +/- 19 months) were obtained from medical records and by patient questioning. RESULTS: Bile duct sludge occurred in 14% (31/228) of patients and was more common in females. After endoscopic clearance, CBD stones recurred in 17% (33/197) of the patients with CBD stones, and in 16% (5/31) of the patients with BDS (p = 0.99). Common bile duct dilation was less common in the sludge group. The other known risk factors for recurrent CBD stones (age, previous open cholecystectomy, bile duct angulation, and the presence of a peripampullary diverticulum) were not statistically different between the two groups. CONCLUSIONS: The findings indicate that the clinical significance of symptomatic BDS is similar to that of CBD stones. Bile duct sludge seems to be an early stage of choledocholithiasis.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Coledocolitiasis/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Coledocolitiasis/epidemiología , Coledocolitiasis/cirugía , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo , Esfinterotomía Endoscópica
6.
Surg Endosc ; 20(10): 1594-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16858527

RESUMEN

BACKGROUND: Endoscopic sphincterotomy and stone extraction are standard procedures for the removal of bile duct stones. Stone recurrence can, however, occur in up to 25% of cases. Risk factors have been poorly defined, but are believed to be related to bile stasis. This study investigated whether an angulated common bile duct (CBD) that may predispose to bile stasis influences symptomatic stone recurrence after successful endoscopic therapy. METHODS: This study included 232 consecutive patients (mean age, 64.1 years; 86 men) who had undergone therapeutic endoscopic retrograde cholangiopancreatography for bile duct stones. Data from the follow-up period (36 +/- 17 months) were obtained from medical records and patient questioning. Common bile duct angulation and diameter were measured from the cholangiogram after stone removal. RESULTS: Symptomatic bile duct stones recurred in 16% of the patients (36/232). Three independent risk factors were identified by multivariate analysis: an angulated CBD (angle, < or = 145 degrees; relative risk [RR], 5.2; 95% confidence interval [CI], 2.2-12.5; p = 0.0002), a dilated CBD (diameter, > or = 13 mm; RR, 2.6; 95% CI, 1.2-5.7; p = 0.017), and a previous open cholecystectomy (RR, 2.7; 95% CI, 1.3-5.9; p = 0.0117). Gender, age, urgency of procedure, or a periampullary diverticulum did not influence the recurrence rate. CONCLUSIONS: Angulation of the CBD (< or = 145 degrees) on endoscopic cholangiography, a dilated CBD, and a previous open cholecystectomy are independent risk factors for symptomatic recurrence of bile duct stones. The findings support the role of bile stasis in stone recurrence. Further studies using these data prospectively to identify high-risk patients are warranted.


Asunto(s)
Enfermedades de los Conductos Biliares/patología , Colelitiasis/patología , Conducto Colédoco/patología , Esfinterotomía Endoscópica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de los Conductos Biliares/diagnóstico , Enfermedades de los Conductos Biliares/etiología , Enfermedades de los Conductos Biliares/cirugía , Niño , Colangiografía , Colangiopancreatografia Retrógrada Endoscópica , Colelitiasis/diagnóstico , Colelitiasis/etiología , Colelitiasis/cirugía , Conducto Colédoco/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Factores de Riesgo
7.
Biochim Biophys Acta ; 1390(3): 293-300, 1998 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-9487150

RESUMEN

Changes in the molecular structure of biliary phospholipids were shown to have major effects on cholesterol solubility, carriers and crystallization in human and model biles. This study investigated systematically the effects of varying saturation of the phosphatidylcholine (PC) sn-2 fatty acid on the cholesterol crystallization process in 3 different model biles. Twenty % of the egg PC (EPC) in these biles were replaced by synthetic PC's with 16:0-18:0, 16:0-18:1, or 16:0-18:2 fatty acyl chains. With 18:0 in the sn-2 position, the crystal observation time (COT) was prolonged from 2 days in the control EPC solution to 14 days (p<0.05). The crystal growth rate (CGR) was reduced from 0.1 OD/day to unmeasurable levels, and the total crystal mass on day 14 decreased by 86%. The introduction of one (18:1), and two (18:2) double bonds in the sn-2 fatty acid rapidly reversed these effects. Ultracentrifugal analysis showed precipitable cholesterol as monohydrate crystals. In the 16:0-18:0 test solution, most of the precipitable cholesterol remained in the supersaturated multilamellar vesicles. Saturation of the biliary PC sn-2 fatty acyl chain prolongs the COT, slows the CGR, reduces the crystal mass, and extends cholesterol solubility in multilamellar vesicles. Desaturation of the sn-2 fatty acid reverses these effects.


Asunto(s)
Bilis/química , Colesterol/química , Ácidos Grasos/química , Fosfolípidos/química , Colesterol/análisis , Cristalización , Ácidos Grasos/farmacología , Ácidos Grasos Insaturados/química , Humanos , Fosfatidilcolinas/química , Fosfolípidos/farmacología , Espectrofotometría , Factores de Tiempo , Ultracentrifugación
8.
FEBS Lett ; 340(1-2): 78-82, 1994 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-8119412

RESUMEN

The evolution of microstructures present in human gallbladder and hepatic bile was observed simultaneously by video-enhanced light microscopy (VELM) and transmission electron microscopy of vitrified specimens (cryo-TEM), as a function of time after withdrawal from patients. Fresh centrifuged gallbladder bile samples contained small (6 nm) spherical micelles in coexistence with vesicles (40 nm). Out of the seven bile samples investigated four contained, in addition, two types of elongated aggregates that have not been previously described. Uncentrifuged gallbladder bile also contained a mixture of ribbon- and plate-like crystals seen by VELM, but not by cryo-TEM. In aged (3-6-week-old) gallbladder bile samples VELM also revealed spiral and helical crystal structures. No such crystals were present in hepatic bile samples, although microcrystals, not observable by VELM were seen by cryo-TEM in addition to micelles and vesicles. The similarity of these observations to those observed in bile models lends strong support for the validity of the model systems. Furthermore, the presence of microcrystals in hepatic bile samples, apparently devoid of crystals by light microscopy, indicates that under certain conditions the common criterion of 'nucleation time' (NT), based on light microscopy, does not represent the real time of nucleation. In the human bile samples investigated in this study the dissociation between NT and the time of observation of microcrystals was seen in hepatic but not in gallbladder bile samples. Hence, crystal growth may be rate limiting only in dilute biles.


Asunto(s)
Bilis/química , Lípidos/análisis , Microscopía/métodos , Bilis/metabolismo , Colelitiasis/metabolismo , Vesícula Biliar/metabolismo , Humanos , Hígado/metabolismo , Microscopía Electrónica/métodos
9.
Aliment Pharmacol Ther ; 11(3): 569-73, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9218084

RESUMEN

BACKGROUND: Recent clinical trials have demonstrated that methotrexate may have an important therapeutic role in the treatment of patients with inflammatory bowel disease, who are either refractory or intolerant to traditional medical therapy. The aim of this study was to evaluate the pharmacokinetics of low-dose oral methotrexate in patients with inflammatory bowel disease. METHODS: Methotrexate (12.5 mg) was given orally to nine patients with inflammatory bowel disease: five with Crohn's disease, and four with ulcerative colitis, and to six patients with rheumatoid arthritis who served as a control group. Blood samples were drawn at specific intervals to evaluate methotrexate plasma levels. RESULTS: Methotrexate was rapidly absorbed in all patients. Peak concentrations (Cmax) varied considerably, ranging from 0.25-0.87 micro M. The mean Cmax values were similar in all patient groups (0.59 +/- 0.12, 0.69 +/- 0.16 and 0.54 +/- 0.18 micro M, P not significant) for Crohn's disease, ulcerative colitis and rheumatoid arthritis, respectively. The mean area under curve in 120 min (AUC0-120) was also similar in all patient groups (32.9 + 11.3, 43.6 + 9.9 and 41.8 + 14.9 ng.min/mL, P not significant) for Crohn's disease, ulcerative colitis and rheumatoid arthritis, respectively. The mean time to reach Cmax, (tmax), varied between patient groups (84, 112 and 95 min, respectively, with a significant difference, P < 0.02, between the Crohn's disease and ulcerative colitis groups. A negative correlation was found between methotrexate dosage/kg and Cmax (r = -0.74) only in Crohn's disease patients but not in the other patient groups. CONCLUSIONS: Orally administered methotrexate is well absorbed in patients with inflammatory bowel disease including those with severe small bowel disease or resection. If methotrexate is proven to be effective in inflammatory bowel disease, it should be administered orally.


Asunto(s)
Antagonistas del Ácido Fólico/farmacocinética , Enfermedades Inflamatorias del Intestino/metabolismo , Metotrexato/farmacocinética , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
10.
Aliment Pharmacol Ther ; 10(6): 1015-9, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8971304

RESUMEN

BACKGROUND: Triple therapy with omeprazole, clarithromycin, and tinidazole (OCT) has been found to be highly effective against Helicobacter pylori infection. However, its efficacy as a second line regimen for patients who failed metronidazole-based triple therapy has not been evaluated. AIM: The aim of this study was to evaluate the efficacy of low-dose, short-term OCT therapy in an Israeli population, and to compare results obtained in previously treated and untreated patients. METHODS: Patients with duodenal or gastric ulcers and chronic antral gastritis with H. pylori infection as assessed by rapid urease test and/or 14C urea breath test (14C-UBT), were studied. All patients received omeprazole 20 mg b.d., clarithromycin 250 mg b.d. and tinidazole 500 mg b.d. for 7 days. Eradication was assessed by 14C-UBT 4 weeks after treatment. RESULTS: One hundred and fourty-four patients (M/F = 81/63) were enrolled (mean age 48.1 years, range 12-78). Eradication of H. pylori was significantly different between patients who were initially treated with this regimen (90/94, 96%) and patients who had previously failed to eradicate H. pylori with standard triple therapy (27/50, 54%). Moreover, the eradication rate was significantly decreased in patients with more than one previous failure (9/22, 41%) compared to that in patients with only one failure (18/29, 62%). No other differences such as age, gastric pathology, ethnic origin, smoking habits, or pre-treatment urease activity were found to influence the eradication rate. CONCLUSIONS: One-week low-dose triple therapy with OCT is highly effective as an initial therapy in eradicating H. pylori infection. The efficacy is significantly lower when given as a second line treatment in patients who have previously failed to eradicate H. pylori with bismuth-based standard triple therapy.


Asunto(s)
Antibacterianos/uso terapéutico , Antiulcerosos/uso terapéutico , Claritromicina/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Omeprazol/uso terapéutico , Tinidazol/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Esquema de Medicación , Quimioterapia Combinada , Úlcera Duodenal/tratamiento farmacológico , Úlcera Duodenal/microbiología , Femenino , Gastritis/tratamiento farmacológico , Gastritis/microbiología , Humanos , Masculino , Metronidazol/uso terapéutico , Persona de Mediana Edad , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/microbiología , Insuficiencia del Tratamiento
11.
J Am Geriatr Soc ; 47(6): 720-2, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10366173

RESUMEN

OBJECTIVE: To evaluate the efficacy of 1-week triple therapy with omeprazole, clarithromycin,and tinidazole (OCT) in Helicobacter pylori-positive older patients with dyspepsia. DESIGN: A prospective, nonrandomized therapeutic study. SETTING: The primary care and referral center of a gastroenterological outpatient clinic at a central university hospital serving an urban population (>1 million) in Israel. PARTICIPANTS: The study group consisted of 134 patients (71 men, and 63 women) more than 60 years old who were referred for evaluation of symptoms of dyspepsia and were endoscopically diagnosed as H. pylori positive. The patients were divided into two groups: those who received their first course of anti-H. Pylori therapy during this study (Group 1) and those who had previously received standard metronidazole and bismuth combination therapies that failed to eradicate the H. pylori (Group 2). MEASUREMENTS: All the patients underwent upper gastrointestinal endoscopy, and H. pylori infection was confirmed by a rapid urease test (CUTest) and/or histological staining. Therapeutic efficacy was assessed by a 13C-urea breath test 4 weeks after completion of treatment. RESULTS: The mean age of the study population was 68.8 years (range 60-87). There were 112 patients in Group 1 and 22 patients in Group 2. Endoscopic findings were: gastritis (in 46), gastric ulcer (8), duodenal ulcer (52), and duodenitis (28). The H. pylori eradication rate was significantly higher in Group 1 patients (104/112, 92.9%) than in patients of Group 2 (15/22, 68.2%). There was no difference in the eradication rate in relation to gender, endoscopic diagnosis, more advanced age, place of birth, or smoking habits. The compliance in both groups was equally good, and no major side effects were recorded. CONCLUSIONS: A 1-week OCT triple therapy is well tolerated and effective as first line therapy for H. pylori among older people. It is less effective in patients previously treated.


Asunto(s)
Antiulcerosos/uso terapéutico , Dispepsia/tratamiento farmacológico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Omeprazol/uso terapéutico , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Distribución de Chi-Cuadrado , Claritromicina/uso terapéutico , Intervalos de Confianza , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Tinidazol/uso terapéutico
12.
Histol Histopathol ; 15(3): 761-70, 2000 07.
Artículo en Inglés | MEDLINE | ID: mdl-10963121

RESUMEN

The study of physical-chemical factors and pathways leading to cholesterol crystallization in bile has important clinical relevance. The major processes in cholesterol gallstone formation can be subdivided into nucleation, formation and precipitation of solid crystals (crystallization), crystal growth, crystal agglomeration and stone growth. A clear understanding of the microstructural events occurring during the earliest stages of these processes in bile is crucial for the identification of factors possibly delaying or preventing precipitation of cholesterol crystals and, therefore, gallstone formation in bile. Detection and characterization of microstructures in native and model biles can be achieved by both direct and indirect techniques. Direct imaging techniques provide more readily interpretable information, but sample preparation problems, particularly for electron microscopy, are a source of artifacts. Moreover, microscopic techniques provide only qualitative data without the possibility to quantitate or to analyse the composition of microstructures. Several indirect techniques have been used to obtain additional microstructural information about nucleating bile. These techniques have the disadvantage of often being model dependent in addition to constraints specific for each method. The systematic, judicious use of a combination of complementary direct and indirect techniques have led to a comprehensive understanding of the various microstructural processes and interactions occurring during bile secretion, flow in the biliary tract and storage in the gallbladder. This forms the basis for our current understanding of cholesterol nucleation, crystallization and gallstone formation.


Asunto(s)
Bilis/metabolismo , Colelitiasis/patología , Colesterol/metabolismo , Animales , Colelitiasis/metabolismo , Humanos
13.
Microsc Res Tech ; 39(1): 85-96, 1997 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-9329021

RESUMEN

Investigation of cholesterol crystallization is essential for the understanding of gallstone formation. Previous work has revealed a variety of aggregates of different sizes and shapes prior to the appearance of "classical" plate-like cholesterol monohydrate crystals both in native biles and model systems. In this article, we review existing data based on various microscopic techniques and present data on microstructural pathways leading to cholesterol crystal formation in two different bile models and in native bile. In continuation of our recent investigation of microstructures in nucleating human bile, we now present data suggesting that polymorphism is not limited to complex native bile, but also appears in two, simplified model systems. These studies employed cryo-transmission electron microscopy (cryo-TEM) and video-enhanced light microscopy, using Nomarski optics (VELM). Only the combined use of these two complementary, non-perturbing direct methods can cover the whole range of microstructures ranging from a few nanometers to several microns. Concentrated isotropic solutions of bile models, composed of cholesterol, lecithin and taurocholate, were diluted to induce cholesterol supersaturation and start an evolution of microstructures, leading to cholesterol crystallization. Initially, small spheroidal micelles were observed by cryo-TEM. Subsequently, uni-, oligo- and multilamellar vesicles, compatible with structures seen at the same time by VELM, appeared in coexistence with micelles. Thereafter, during a dynamic phase of cholesterol crystallization, filaments, tubular and helical microstructures, as well as classical plate-like cholesterol monohydrate crystals were noted by light microscopy. Eventually, large plate-like crystals were observed by VELM, while cryo-TEM revealed only small spheroidal micelles. The crystallization process in native human bile during ex vivo incubation was found to bear close resemblance to the findings in the model systems, further supporting the applicability of these systems to the exploration of microstructural aspects of nucleating human bile.


Asunto(s)
Bilis/química , Estructura Molecular , Colelitiasis/metabolismo , Colesterol/química , Cristalización , Humanos , Micelas , Microscopía Electrónica/métodos , Microscopía por Video
14.
Clin Biochem ; 34(3): 183-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11408015

RESUMEN

OBJECTIVE: (i) to characterize the profile of tumor necrosis factor alpha (TNF alpha), interleukin-6 (IL-6), IL 10, Fas-ligand and transforming growth factor beta (TGF beta), chronic hepatitis C (HCV) patients with genotype 1; (ii) to determine the influence of triple therapy (TT) with interferon alpha (IFN alpha) + ribavirin + ursodeoxycholic acid on these cytokines and (iii) to establish the relationship between the pro-inflammatory cytokines and the outcome of treatment. DESIGN AND METHODS: 22 patients infected with HCV-genotype 1 a/b and non responsive to IFN-alpha monotherapy were enrolled in the TT. The controls were 49 HCV naïve patients with genotype 1 a/b. Cytokine levels were measured using enzyme-linked immunosorbent assay (ELISA). RESULTS: The baseline TNF alpha values (pg/mL) in the sustained responders (SRs) (63+/-3) were significantly lower than non-responders (NRs) (140+/-16) (p < 0.001). Baseline Fas (ng/mL) levels were also lower in SRs (4.3+/-0.2) than NRs (5.4+/-0.4) (p < 0.05). CONCLUSIONS: Fas and TNF alpha may be used as serological markers of inflammation and effectiveness of therapy.


Asunto(s)
Citocinas/sangre , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Ribavirina/uso terapéutico , Ácido Ursodesoxicólico/uso terapéutico , Adulto , Quimioterapia Combinada , Ensayo de Inmunoadsorción Enzimática , Femenino , Genotipo , Hepatitis C Crónica/sangre , Humanos , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Ribavirina/administración & dosificación , Ácido Ursodesoxicólico/administración & dosificación
15.
Clin Chim Acta ; 249(1-2): 59-66, 1996 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-8737592

RESUMEN

We examined the effects of freezing and thawing upon the nucleation time and the distribution of cholesterol between micelles and vesicles in 9 human gallbladder and 7 hepatic biles. The nucleation time was significantly longer after freezing when compared to fresh samples (22.4 +/- 2.6 vs. 7.4 +/- 1.9 days, respectively). Concomitantly, a substantial shift of cholesterol from vesicles to micelles was noted, with the proportion of vesicular cholesterol decreasing from 26.5% +/- 6.0% in fresh biles to 8.6% +/- 2.3% after freezing. These effects were observed in all types of human biles, regardless of origin, cholesterol saturation or initial presence of cholesterol crystals, and were most notable after the first week of freezing. The decrease in vesicular cholesterol in all biles and the increase in nucleation time of gallbladder biles correlated with the time the samples had been in a frozen state. It is concluded that the lithogenic properties of human bile are not maintained during storage at -20 degrees C. Freezing results in a shift of cholesterol from vesicles to micelles and reduces the tendency of cholesterol to crystallize from bile samples.


Asunto(s)
Bilis/química , Colesterol/análisis , Criopreservación , Colelitiasis/química , Cristalización , Congelación , Humanos , Micelas
16.
Lipids ; 31(3): 295-303, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8900459

RESUMEN

The role of phospholipids in biliary cholesterol solubilization and crystallization has only recently begun to be appreciated. Phospholipid vesicles are believed to be the metastable carrier from which cholesterol nucleates. Cholesterol crystallization is influenced by the phospholipid species in bile. Feeding rats and hamsters with diets enriched in phospholipids or their precursors, especially ethanolamine, resulted in reduced cholesterol saturation of bile. Although whole phospholipids are normal dietary constituents, the effects and safety of phospholipid components have not been tested in humans. In the present study, we have evaluated the effects of a dietary phospholipid mixture, enriched with phosphatidylethanolamine, on human bile and red blood cell membrane lipid composition. Five ambulatory volunteers having a chronic indwelling T-tube, with an intact enterohepatic circulation, were investigated. Thirty-six grams of phospholipids (54% phosphatidylethanolamine, 54% linoleyl acyl chains) were added to their daily diet for fourteen days. Biliary nucleation time, cholesterol carriers, as well as plasma, red blood cell membrane, and bile lipid compositions, were monitored. Following phospholipid supplementation, the proportion of linoleyl chains (18:2) in biliary phospholipids increased significantly from 31.1 +/- 1.2 to 37.7 +/- 5.3%, while that of oleyl chains (18:1) decreased from 11.4 +/- 1.6 to 9.6 +/- 1.1%. These changes were accompanied by an increase of linoleate and its metabolite, arachidonate, in red cell membranes. Phospholipid feeding did not cause any side effects, and no significant changes in biliary nucleation time, cholesterol, phospholipid, or bile salt concentrations, or in the distribution of cholesterol within micelles or vesicles. We conclude that phospholipid feeding is safe, and can be effective as a vehicle for lecithin fatty acyl chain modulation of bile and lipid membranes. These findings may provide a basis for a controlled modulation of biliary phospholipids to increase cholesterol solubility in bile.


Asunto(s)
Bilis/química , Lípidos de la Membrana/metabolismo , Fosfolípidos/farmacología , Adulto , Anciano , Bilis/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Dieta , Eritrocitos/metabolismo , Ácidos Grasos/análisis , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Femenino , Humanos , Masculino , Lípidos de la Membrana/química , Persona de Mediana Edad , Fosfatidilcolinas/química , Fosfatidiletanolaminas/metabolismo , Fosfatidiletanolaminas/farmacología , Fosfolípidos/química , Fosfolípidos/metabolismo
17.
Lipids ; 36(10): 1135-40, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11768158

RESUMEN

We have recently synthesized fatty acid bile acid conjugates (FABAC) that were able to reduce and retard cholesterol crystallization in model and human biles. When given orally, they prevented the formation of cholesterol crystals in the bile of hamsters. The aim of the present study was to determine whether the FABAC are cholesterol solubilizers, whether they can dissolve pre-existing crystals, whether they can prevent the formation of cholesterol gallstones, and to investigate the optimal type of bond between the fatty acid and bile acid. The presence of cholesterol crystals was determined by light microscopy, and the total crystal mass of precipitated crystals was measured by chemical means. Inbred (C57J/L) mice on a lithogenic diet were used to evaluate cholesterol crystal formation, dissolution, and gallstone formation in vivo. Arachidyl amido cholanoic acid (Aramchol) was the FABAC used in the present experiments. At equimolar amounts, the cholesterol-solubilizing capacity of Aramchol was higher than that of taurocholate and similar to that of phosphatidylcholine. The addition of Aramchol dissolved approximately 50% of pre-existing crystals in model bile solutions. The same phenomenon was demonstrated in human bile ex vivo, with a dose-response effect. All inbred mice developed cholesterol crystals in bile after 10-14 d on the lithogenic diet. Thereafter, supplementation of the diet with Aramchol progressively reduced the proportion of mice with crystals to 25% after 28 d. On the lithogenic diet, 100% of inbred mice developed cholesterol gallstones in the gallbladder by day 21. None of the mice whose diet was supplemented with 0.5 mg or 1.0 mg of Aramchol/d developed stones or crystals. FABAC are a new class of molecules that are cholesterol solubilizers and which are able to dissolve cholesterol crystals in bile. Upon oral administration, they dissolve pre-existing cholesterol crystals and prevent the formation of gallstones in gallstone-susceptible mice.


Asunto(s)
Ácidos y Sales Biliares/uso terapéutico , Colelitiasis/prevención & control , Colesterol/química , Animales , Bilis/química , Colelitiasis/química , Colesterol/análisis , Ácidos Cólicos , Cristalización , Dieta , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Solubilidad , Soluciones
18.
Isr Med Assoc J ; 2(12): 892-5, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11344768

RESUMEN

BACKGROUND: Cigarette smoking has long been regarded as an important factor in the pathogenesis of peptic ulcer disease. OBJECTIVE: To investigate whether cigarette smoking has an additive effect on the clinical presentation and course of disease in Helicobacter pylori-positive dyspeptic patients. PATIENTS AND METHODS: The study group comprised 596 consecutive H. pylori-positive dyspeptic patients (334 males and 262 females, mean age 50.6, range 12-81 years). Following upper gastrointestinal endoscopy, patients were subdivided by diagnosis as follows: Non-ulcer patient group (n = 312: gastritis 193, duodenitis 119), gastric ulcer (n = 19), and duodenal ulcer (n = 265). H. pylori infection was confirmed by histology and/or rapid urease test. In addition, 244 patients had a positive 14C-urea breath test prior to antimicrobial treatment. The patients' medical history and smoking habits were obtained using a detailed questionnaire completed by the patients and their referring physicians. RESULTS: There were 337 non-smoking patients, 148 current smokers and 111 past smokers. Gastric and duodenal ulcers were significantly less prevalent in non-smokers than in current or past smokers (gastric 1.8%, 4.1%, 6.3%; duodenal 39.8%, 50%, 51.4%, respectively) (P < 0.05). The incidence of gastrointestinal bleeding was significantly lower in non-smokers than in current or past smokers (7.1%, 8.1% and 20.7%, respectively) (P < 0.05). Bacterial density, as assessed by the UBT value in 244 patients, was higher in non-smokers (mean 352.3 +/- 273 units) than in past smokers (mean 320.8 +/- 199) or current-smokers (mean 229.9 +/- 162) (P < 0.05). Logistic regression analysis revealed that male gender, current smoking, and immigration from developing countries were all significant independent risks for developing duodenal ulcer, while only past smoking was associated with a higher rate of upper gastrointestinal bleeding in the past. CONCLUSIONS: In H. pylori-positive dyspeptic patients, current smoking as well as male gender and immigration from developing countries are associated with an increased risk for duodenal ulcer. This effect does not seem to be related to the bacterial density or increased urease activity of H. pylori organisms.


Asunto(s)
Dispepsia/etiología , Infecciones por Helicobacter/etiología , Helicobacter pylori/aislamiento & purificación , Úlcera Péptica Hemorrágica/etiología , Fumar/efectos adversos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Pruebas Respiratorias/métodos , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Sistema Digestivo/patología , Dispepsia/diagnóstico , Dispepsia/epidemiología , Femenino , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/diagnóstico , Úlcera Péptica Hemorrágica/epidemiología , Valores de Referencia , Factores de Riesgo , Distribución por Sexo , Urea/análisis
19.
Arch Physiol Biochem ; 120(3): 99-111, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25030769

RESUMEN

OBJECTIVE: Our objective was to test the contribution of dietary enrichment in essential or saturated fatty acids, in normocaloric diets, on the lipid accumulation and insulin resistance in the adult offspring in a C57Bl6/J mice model. METHODS: Pregnant mothers were fed normocaloric diets containing 6% fat enriched in essential fatty acids (EFA): alpha-linolenic (ALA-18:3, n-3), linoleic (LA-18:2, n-6), or saturated fatty acids (SFA). After a washing-out period with regular diet, the offspring received a high-fat diet before euthanization. RESULTS: Adult mice fed maternal ALA showed lower body weight gain and lower liver fat accumulation, lower HOMA index and lower stearoyl-CoA desaturase (SCD1) activity than those fed maternal SFA. CONCLUSION: The results observed using this novel model suggest that ALA in maternal diet may have the potential to inhibit insulin resistance in adult offspring.


Asunto(s)
Envejecimiento/fisiología , Suplementos Dietéticos/análisis , Resistencia a la Insulina , Ácido alfa-Linolénico/farmacología , Tejido Adiposo/efectos de los fármacos , Adiposidad/efectos de los fármacos , Envejecimiento/sangre , Envejecimiento/efectos de los fármacos , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Ácidos Grasos/farmacología , Femenino , Insulina/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Madres , Embarazo , Ácido alfa-Linolénico/administración & dosificación , Ácido alfa-Linolénico/análisis , Ácido alfa-Linolénico/sangre
20.
Cancer Gene Ther ; 19(6): 374-81, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22498722

RESUMEN

BC-819 is a DNA plasmid that was developed to target the expression of diphtheria-toxin gene under the control of H19 regulatory sequences. BC-819 has the potential to treat pancreatic cancer that overexpresses the H19 gene. The objectives were to assess the safety, tolerability, pharmacokinetics and preliminary efficacy of BC-819 administered intratumorally in subjects with unresectable, locally advanced, non-metastatic pancreatic cancer. Nine patients with unresectable pancreatic adenocarcinoma were enrolled in an open-label, dose-escalation trial. Subjects were entered into one out of two cohorts with escalating doses of BC-819. Each cohort received 2 weeks of twice weekly intratumoral injection of BC-819 under computerized tomography (CT) (n = 3) or endoscopic ultrasound (EUS) (n = 6) guidance. Patients were assessed by CT or positron emission tomography (PET)/CT during week 4 for tumor response. The maximum tolerated dose of BC-819 was not reached in this study at the highest dose. Asymptomatic elevation of lipase, which was considered as an adverse event with dose-limiting toxicity, occurred in only one subject in the high-dose group and was resolved spontaneously. The tumors did not increase in size 4 weeks after initiating treatment. Two weeks after completing the treatment, the two subjects who went on to receive subsequent chemotherapy or chemoradiation therapy, pancreatic tumors were downstaged and considered surgically resectable. Remarkably, three of the six subjects in cohort no. 2 evaluated at month 3 had a partial response. BC-819 can be safely administered intratumorally via EUS- or CT-guided injection at a dose of at least 8 mg per injection weekly twice. BC-819 given locally in combination with systemic chemotherapy may provide an additional therapeutic benefit for the treatment of pancreatic cancer.


Asunto(s)
Adenocarcinoma/terapia , Toxina Diftérica/genética , Neoplasias Pancreáticas/terapia , Fragmentos de Péptidos/genética , Plásmidos/administración & dosificación , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Anciano , Anciano de 80 o más Años , Femenino , Terapia Genética , Vectores Genéticos , Humanos , Inyecciones Intralesiones , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Imagen Multimodal , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Plásmidos/efectos adversos , Plásmidos/farmacocinética , Tomografía de Emisión de Positrones , Regiones Promotoras Genéticas , ARN Largo no Codificante , ARN no Traducido/genética , ARN no Traducido/metabolismo , Tasa de Supervivencia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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