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Jose Behar - One of the best experts on this subject based on the ideXlab platform.
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Excess membrane Cholesterol alters human gallbladder muscle contractility and membrane fluidity.
Gastroenterology, 1999Co-Authors: Qian Chen, Piero Biancani, Joseph Amaral, Jose BeharAbstract:Abstract Background & Aims: The relationship between muscle contractility, plasma membrane Cholesterol, and fluidity was investigated in human gallbladders with gallStones. Methods: Isolated gallbladder muscle cells were used to measure contraction. Plasma membranes of gallbladder muscle were purified in a sucrose gradient and measured for Cholesterol content and Cholesterol/phospholipid mole ratio. Membrane fluidity was determined by using fluorescence polarization and was expressed as the reciprocal of anisotropy. Results: The maximal contraction induced by cholecystokinin octapeptide was significantly less in gallbladders with Cholesterol Stones than in those with pigment Stones. The membrane Cholesterol content and Cholesterol/phospholipid mole ratio were significantly higher in gallbladders with Cholesterol Stones than in those with pigment Stones. Membrane anisotropy was also higher than in gallbladders with pigment Stones, reflecting lower membrane fluidity in gallbladders with Cholesterol Stones. After muscle cells from Cholesterol Stone gallbladders were incubated with Cholesterol-free liposomes for 4 hours, cholecystokinin octapeptide–induced contraction, membrane Cholesterol content and Cholesterol/phospholipid ratio, and membrane fluidity returned to normal levels. Conclusions: Gallbladder muscle from patients with Cholesterol Stones has increased membrane Cholesterol/phospholipid mole ratio and decreased membrane fluidity resulting in impaired muscle contractility. These abnormalities are corrected by removing the excess Cholesterol from the plasma membranes. GASTROENTEROLOGY 1999;116:678-685
Piero Portincasa - One of the best experts on this subject based on the ideXlab platform.
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Biliary proteins and their redox status changes in gallStone patients
European journal of clinical investigation, 2009Co-Authors: I. Grattagliano, A Di Ciaula, Giuseppe Palasciano, D. Q-h Wang, Catia V. Diogo, Piero PortincasaAbstract:Background Proteins might act as pronucleating agents of Cholesterol crystallization in bile. However, little is known about the redox status of biliary proteins in humans and their interaction with crystallization of biliary Cholesterol. Materials and methods Gallbladder biles were obtained at cholecystectomy from 86 symptomatic patients with either Cholesterol gallStones (32 multiple and 32 solitary Stones) or pigment Stones (n = 22), and studied for protein redox status [carbonyl and sulfhydryl (PSH) concentrations], total lipid and protein levels and Cholesterol saturation index (CSI). First appearance of Cholesterol crystals in ultrafiltered bile (crystal observation time, COT) was studied with polarizing light microscopy during 21 days. Results Patients with Cholesterol Stones had significantly shorter COT (3 days vs. >21 days, P solitary > pigment Stones, P = 0·009) and total protein concentration (high > low levels, P = 0·004). COT was negatively correlated with total protein content (r = −0·45, P = 0·03). Conclusions Biles with Cholesterol Stones show high CSI and total protein concentration, and rapid COT, which is even faster in patients with multiple Stones and high protein concentration. Low PSH levels in Cholesterol Stone patients point to a biochemical shift, potentially able to affect Cholesterol crystallization.
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smooth muscle function and dysfunction in gallbladder disease
Current Gastroenterology Reports, 2004Co-Authors: Piero Portincasa, Agostino Di Ciaula, G P VanbergehenegouwenAbstract:The gallbladder epithelium and smooth muscle layer are exposed to concentrated biliary solutes, including Cholesterol and potentially toxic hydrophobic bile salts, which are able to influence muscle contraction. Physiologically, gallbladder tone is regulated by spontaneous muscle activity, hormones, and neurotransmitters released into the muscle from intrinsic neurons and extrinsic sympathetic nerves. Methods to explore gallbladder smooth muscle function in vitro include cholecystokinin (CCK) receptorbinding studies and contractility studies. In human and animal models, studies have focused on cellular and molecular events in health and disease, and in vitro findings mirror in vivo events. The interplay between contraction and relaxation of the gallbladder muscularis leads in vivo to appropriate gallbladder emptying and refilling during fasting and postprandially. Defective smooth muscle contractility and/or relaxation are found in Cholesterol Stone-containing gallbladders, featuring a type of gallbladder leiomyopathy; defects of CCKA receptors and signal transduction may coexist with abnormal responses to oxidative stress and inflammatory mediators. Abnormal smooth musculature contractility, impaired gallbladder motility, and increased stasis are key factors in the pathogenesis of Cholesterol gallStones.
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gallbladder motility and Cholesterol crystallization in bile from patients with pigment and Cholesterol gallStones
European Journal of Clinical Investigation, 2000Co-Authors: Piero Portincasa, A Di Ciaula, G Vendemiale, Vincenzo O Palmieri, A Moschetta, G P Vanbergehenegouwen, Giuseppe PalascianoAbstract:Background Little is known about gallbladder motility in patients with black pigment Stones when compared to Cholesterol gallStone patients, or about their relationship to biliary composition, crystallization and Stone characteristics. Design Fasting and postprandial gallbladder volumes were studied by ultrasonography in 49 gallStone patients with pigment (n = 14) or Cholesterol (n = 35) Stones and 30 healthy controls. After cholecystectomy Stone composition, gallbladder wall inflammation, Cholesterol saturation index and appearance of platelike Cholesterol crystals in bile were evaluated in gallStone patients. Results Fasting gallbladder volume was significantly (P < 0.05) increased in Cholesterol Stone patients (31.7 ± 1.9 mL) but not in pigment Stone patients (21.9 ± 3.1 mL), compared to controls (21.0 ± 1.5 mL). Postprandial emptying was delayed in patients (half-emptying time: 31 ± 2 min, 35 ± 3 min, 24 ± 2 min in Cholesterol Stone patients, pigment Stone patients and controls, respectively, P < 0.05) and incomplete (residual volume: 43.2 ± 2.7%, 40.0 ± 4.3%, 15.8 ± 1.6% min in Cholesterol Stone patients, pigment Stone patients and controls, respectively, P < 0.05). The inflammation of the gallbladder wall was mild or absent in all cases. Biliary Cholesterol saturation index was 152.3 ± 8.5% and 92.9 ± 4.8% in patients with Cholesterol and pigment Stones, respectively (P < 0.01). Whereas Cholesterol crystals never appeared during 21 days in biles from patients with pigment Stones, crystal observation time in patients with Cholesterol gallStone was 5 days (median) and was significantly shorter in patients with multiple (4 days) than in patients with solitary (12 days) Cholesterol Stones (P = 0.0019). Conclusions Patients with black pigment Stones who do not have excess Cholesterol and do not grow Cholesterol crystals in bile have decreased gallbladder emptying, although to a lesser extent than patients with Cholesterol Stones. Thus, gallbladder stasis is likely to put a subset of subjects at risk for the formation of pigment gallStones, and pathogenic mechanisms need to be further investigated.
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Cholesterol crystallization in human gallbladder bile: Relation to gallStone number, bile composition, and apolipoprotein E4 isoform
Hepatology (Baltimore Md.), 1998Co-Authors: K.j. Van Erpecum, Piero Portincasa, B. J. M. Van De Heijning, G. P. Van Berge Henegouwen, Erik Eckhardt, Geesje M. Dallinga-thie, Albert K. GroenAbstract:Patients with multiple Cholesterol gallStones are at increased risk of recurrence after nonsurgical therapy, possibly because of fast biliary Cholesterol crystallization. Serum apolipoprotein E4 (apo E4) is a risk factor for primary Cholesterol gallStone formation as well as recurrence. We examined potential effects of Stone number and apolipoprotein E genotype on crystallization and on various crystallization-influencing factors in gallbladder biles of 36 Cholesterol Stone patients (25 multiple Stones: 10 carrying the ϵ4 allele). Biliary Cholesterol saturation, bile salt composition or concentrations of total protein, immunoglobulin (Ig)A, IgG, α1-acid glycoprotein, haptoglobin, or mucin—all crystallization promoters—did not differ between multiple and solitary Stone patients, apparently not explaining different speed of crystallization (crystal observation time 3.5 ± 0.6 days vs. 12.7 ± 2.4 days, respectively; P = .0003). In contrast, biliary aminopeptidase-N activities (2,607 ± 592 mU/mL vs. 947 ± 185 mU/mL; P = .04) were higher and IgM levels (179 ± 39 vs. 65 ± 8 mg/L; P = .09) tended to be higher in the case of multiple Stones. Although patients carrying the ϵ4 allele had similar Stone numbers and crystallization as patients without the ϵ4 allele, their Cholesterol saturation index (CSI) was lower (1.08 ± 0.09 vs. 1.54 ± 0.13; P = .01), whereas total protein and bile salt concentrations tended to be higher with preferential taurine-conjugation. In conclusion, fast Cholesterol crystallization is associated with multiple Stones but not with apolipoprotein E4. Whereas fast crystallization may contribute to high recurrence rates after nonsurgical therapy in case of multiple gallStones, the mechanism for increased risk of gallStone formation in patients carrying the ϵ4 allele remains unknown.
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Behavior of various Cholesterol crystals in bile from patients with gallStones
Hepatology (Baltimore Md.), 1996Co-Authors: Piero Portincasa, K.j. Van Erpecum, Willem Renooij, A Jansen, M Gadellaa, G. P. Van Berge HenegouwenAbstract:Besides classical plate-like Cholesterol monohydrate crystals, a variety of crystal shapes have recently been described in model biles but their relevance for human gallStone formation is unknown. We therefore studied crystallization behavior in gallbladder bile from Cholesterol Stone patients (54 untreated, 13 ursodeoxycholate-treated) and 6 pigment Stone patients. Bile preparation by ultrafiltration or ultracentrifugation left biliary lipid composition unchanged but plates and their aggregates, and arcs and needles crystallized more extensively while spirals and tubules crystallized less extensively in ultra-centrifuged bile than in ultrafiltered bile. Plates, aggregates, and arcs/needles were seen in 90 percent, 36 percent, and 18 percent of the cases respectively of fresh unfiltered biles of untreated Cholesterol Stone patients, while spirals and tubules were always absent. In ultrafiltered biles arcs/needles, plates and aggregates progressively developed as persistent forms. Spirals and tubules occurred transiently and were associated with increased deoxycholic acid (+41 percent, P = .039) and with more extensive Cholesterol crystallization. Rate/extent of crystallization of all crystal forms was higher (P < .0001) for multiple than solitary Cholesterol Stone patients. Ursodeoxycholate-treated patients had atypical platelike Cholesterol crystals in fresh unfiltered biles that decreased in size at prolonged observation and in 2 cases even dissolved after 15 and 20 days. No crystals ever developed in ultra-filtered bile of ursodeoxycholic acid (UDCA)-treated patients during 21 days. Pigment Stone patients seldom developed crystals. Thus, plates, aggregates and arcs/needles are persistent forms with high crystallization rate in multiple Cholesterol Stone patients. Tubules and spirals are transient forms that are associated with more extensive crystallization. Patients treated with ursodeoxycholate often have atypical crystals in their fresh bile. (Hepatology 1996 Apr;23(4):738-48)
F. Cetta - One of the best experts on this subject based on the ideXlab platform.
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Re: Kawai et al. —bacteria are not important in the formation of pure Cholesterol Stones
The American journal of gastroenterology, 2002Co-Authors: A Cariati, F. CettaAbstract:TO THE EDITOR: In a recent paper concerning pure Cholesterol Stone formation, Kawai et al. (1) analyzed the core of 69 gallStones with molecular-genetic methods such as polymerase chain reaction. Bacterial species in gallStones were identified by DNA sequencing of polymerase chain reaction products.
G P Vanbergehenegouwen - One of the best experts on this subject based on the ideXlab platform.
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smooth muscle function and dysfunction in gallbladder disease
Current Gastroenterology Reports, 2004Co-Authors: Piero Portincasa, Agostino Di Ciaula, G P VanbergehenegouwenAbstract:The gallbladder epithelium and smooth muscle layer are exposed to concentrated biliary solutes, including Cholesterol and potentially toxic hydrophobic bile salts, which are able to influence muscle contraction. Physiologically, gallbladder tone is regulated by spontaneous muscle activity, hormones, and neurotransmitters released into the muscle from intrinsic neurons and extrinsic sympathetic nerves. Methods to explore gallbladder smooth muscle function in vitro include cholecystokinin (CCK) receptorbinding studies and contractility studies. In human and animal models, studies have focused on cellular and molecular events in health and disease, and in vitro findings mirror in vivo events. The interplay between contraction and relaxation of the gallbladder muscularis leads in vivo to appropriate gallbladder emptying and refilling during fasting and postprandially. Defective smooth muscle contractility and/or relaxation are found in Cholesterol Stone-containing gallbladders, featuring a type of gallbladder leiomyopathy; defects of CCKA receptors and signal transduction may coexist with abnormal responses to oxidative stress and inflammatory mediators. Abnormal smooth musculature contractility, impaired gallbladder motility, and increased stasis are key factors in the pathogenesis of Cholesterol gallStones.
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gallbladder motility and Cholesterol crystallization in bile from patients with pigment and Cholesterol gallStones
European Journal of Clinical Investigation, 2000Co-Authors: Piero Portincasa, A Di Ciaula, G Vendemiale, Vincenzo O Palmieri, A Moschetta, G P Vanbergehenegouwen, Giuseppe PalascianoAbstract:Background Little is known about gallbladder motility in patients with black pigment Stones when compared to Cholesterol gallStone patients, or about their relationship to biliary composition, crystallization and Stone characteristics. Design Fasting and postprandial gallbladder volumes were studied by ultrasonography in 49 gallStone patients with pigment (n = 14) or Cholesterol (n = 35) Stones and 30 healthy controls. After cholecystectomy Stone composition, gallbladder wall inflammation, Cholesterol saturation index and appearance of platelike Cholesterol crystals in bile were evaluated in gallStone patients. Results Fasting gallbladder volume was significantly (P < 0.05) increased in Cholesterol Stone patients (31.7 ± 1.9 mL) but not in pigment Stone patients (21.9 ± 3.1 mL), compared to controls (21.0 ± 1.5 mL). Postprandial emptying was delayed in patients (half-emptying time: 31 ± 2 min, 35 ± 3 min, 24 ± 2 min in Cholesterol Stone patients, pigment Stone patients and controls, respectively, P < 0.05) and incomplete (residual volume: 43.2 ± 2.7%, 40.0 ± 4.3%, 15.8 ± 1.6% min in Cholesterol Stone patients, pigment Stone patients and controls, respectively, P < 0.05). The inflammation of the gallbladder wall was mild or absent in all cases. Biliary Cholesterol saturation index was 152.3 ± 8.5% and 92.9 ± 4.8% in patients with Cholesterol and pigment Stones, respectively (P < 0.01). Whereas Cholesterol crystals never appeared during 21 days in biles from patients with pigment Stones, crystal observation time in patients with Cholesterol gallStone was 5 days (median) and was significantly shorter in patients with multiple (4 days) than in patients with solitary (12 days) Cholesterol Stones (P = 0.0019). Conclusions Patients with black pigment Stones who do not have excess Cholesterol and do not grow Cholesterol crystals in bile have decreased gallbladder emptying, although to a lesser extent than patients with Cholesterol Stones. Thus, gallbladder stasis is likely to put a subset of subjects at risk for the formation of pigment gallStones, and pathogenic mechanisms need to be further investigated.
Simanchalo Panigrahi - One of the best experts on this subject based on the ideXlab platform.
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Analysis of Indian Cholesterol gallStones by particle-induced X-ray emission and thermogravimetry-derivative thermogravimetry.
European journal of gastroenterology & hepatology, 2006Co-Authors: Tapash R. Rautray, Venkatathri Vijayan, Simanchalo PanigrahiAbstract:OBJECTIVES: It has been reported that the role of some minor elements plays a significant role in the formation of gallStones. The relationship between minor and trace element concentrations was established in the present investigation and the trace element profile of the current investigation was compared with the literature values of south Indian gallStone samples in order to determine their possible role in Stone formation and growth. The rate of weight loss and classification of Cholesterol type of gallStones were also investigated by thermal analysis. BASIC METHODS: The trace element profile of the Cholesterol gallStones was determined by proton-induced X-ray emission spectroscopic technique and the thermal properties of the Cholesterol Stones were studied by thermogravimetry-derivative thermogravimetry analysis. RESULTS: It was observed that 14 minor/trace elements, namely S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb, were present in the Cholesterol Stone samples. The average concentration of Fe in south Indian (Chennai region) gallStone samples (503.4 ppm) is about 2.5 times more than that of the east Indian gallStone samples (205.0 ppm), whereas the concentration of Fe is still higher in other parts of south India (848.2 ppm) as analysed by Ashok et al. CONCLUSIONS: The higher concentration of Cu (in some parts of south India except the Chennai region) and Fe in south Indian Cholesterol Stone samples may be due to the intake of tamarind (Garcinia camborginia) as their regular food. The thermogravimetry and derivative thermogravimetry curves provided information on the thermal decompositions of Cholesterol Stones.