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Results for “Microscopy, Polarization”

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PubMed1995

High-alkaline protease from Bacillus PB92 entrapped in calcium alginate gel. Physicochemical and microscopic studies.

High-alkaline protease (HAP) has been entrapped in Manugel DMB (an alginate gel) and assayed with two sizes and types of substrates: neutral protein casein and synthetic chromogenic tripeptide substrate, Z-Gly-Pro-Cit-PNA. Increasing the concentration of calcium chloride used for capsule formation decreased the measured enzyme activity with both substrates. Capsules were found to be stable in water for long periods of time, but they dissolved in both phosphate and carbonate-bicarbonate buffers. The pH vs activity profiles of encapsulated enzyme showed pH optima between 10 and 11 with both substrates. The calcium alginate matrix surrounding the enzyme was quite effective in stabilizing the enzyme at 20-25 degrees C and even more so at 4 degrees C. Enzyme stability at 50 degrees C was quite impressive, some enzyme activity being evident even after remaining for 1 wk at this temperature in water. Increasing concentrations of sodium dodecyl sulfate (SDS) were also found to inhibit the protease progressively, whereas a polyhexamethylene biguanidium chloride (PHMBH+Cl-) and SDS:PHMBH+Cl- combination showed the opposite effect. Optical microscopy, especially polarized light microscopy, provided a sensitive physical means of ascertaining some of the structural properties (sphericity, disorganization or organization, distinct layer enveloping the capsules, intensity of the maltese cross) of the capsules with and without enzyme before and after different chemical treatments and the presence or absence of the substrate.

Alginates↗

PubMed2003

Subchondral bone reaction associated with chondral defect and attempted cartilage repair in goats.

Repair of cartilage damage with autologous chondrocyte transplantation (ACT) has become popular in clinical use during the past few years. Although clinical results have mostly been successful, several unanswered questions remain regarding the biological mechanism of the repair process. The aim of this study was to develop a goat model for ACT. The repair was not successful due to the graft delamination, but we characterize the subchondral changes seen after the procedure. A chondral lesion was created in 14 goat knees, operated on 1 month later with ACT, and covered with periosteum or a bioabsorbable poly-L/D-lactide scaffold. After 3 months, only two of the five lesions repaired with ACT showed partly hyaline-like repair tissue, and all lesions (n = 4) with the scaffold failed. Even though the lesions did not extend through the calcified cartilage, the bone volume and collagen organization of bone structure were decreased when assessed by quantitative polarized light microscopy. There was a significant loss of bone matrix and distortion of the trabecular structure of subchondral bone, which extended several millimeters into the bone. The subchondral bone demonstrated strong hyaluronan staining in the bone marrow and cartilaginous areas with signs of endochondral ossification, suggesting structural remodeling of the bone. The goat model used here proved not to be an optimal model for ACT. The changes in subchondral bone may alter the biomechanical properties of the subchondral plate and thus the long-term survival of the repair tissue after ACT.

Animals↗

PubMed2006

Thirty-eight years of stone meetings in Europe.

Of decisive importance for the many research groups all over Europe were the scientific symposia dealing with the theoretical foundations and clinical aspects of urinary stone disease. There were several sources from which today's European Urinary Stone meetings and the "Eurolithiasis Society" itself arose. It was a long way from Leeds in 1968 to Jena 1970, Bonn-Vienna in 1972 and to 11 European meetings from 1989 to 2005. Which developments in urinary stone disease research have been presented at our congresses during the past 40 years? The 1970s and 1980s are the years marked by efforts to measure the important lithogenic substances such as calcium, ionized calcium, uric acid, phosphate, oxalate with reliable methods. Hypercalciuria and specifically mild hyperoxaluria were the topics of numerous investigations in the 1970s, 1980s and 1990s. The calcium-loading test described by Pak has been discussed frequently since its application. It became apparent that oxalic acid is more important in urinary stone formation than hypercalciuria. Of importance were investigations done by Robertson and his colleagues on the influence of diet (in particular, an animal protein-rich diet) on urinary stone formation. Another emphasis of research was investigation of the crystallization process: supersaturation, crystal growth and aggregation are important steps in urinary stone formation. Of great importance in the formation of urinary stones are inhibitors (inhibitory activity): citrate, magnesium, pyrophosphate, macromolecules: GAGs, THP etc. and it became possible in the early 1970s to determine substances such as Tamm-Horsfall protein (THP) and GAGs. Much attention in the 1970s and 1980s was focused on urinary stone analysis (X-ray diffraction, infrared spectroscopy, polarization microscopy) and standardization of these methods. In the mid-1980s, a whole series of epidemiological studies were carried out, with data for the Federal Republic of Germany, East Germany, Czechoslovakia and Austria. The search for "stone-removing" medications, their description and clinical use was the subject of much clinical research and in vitro examinations. A definite advance occurred in the 1980s with the development of new instrumental technologies for the management of urinary stones such as shockwave ("Stosswelle") lithotripsy, percutaneous nephrolithotomy and ureterorenoscopy (" breakthrough innovations"). Since the 8th European Urolithiasis Symposium there have regularly been presentations pertaining to the topic of the molecular basis of inherited lithiasis. The last 10-15 years have shown an increasing turning toward the importance of cellular alterations and supersaturation and their relation to stone formation. In conclusion, I would like to note that it is of decisive importance for the research groups all over Europe to organize scientific symposia dealing with the theoretical foundations and clinical aspects of urinary stone disease under the protection of the European Urolithiasis Society.

Congresses as Topic↗

PubMed2004

Trichothiodystrophy: quantification of cysteine in human hair and nails by application of sodium azide-dependent oxidation to cysteic acid.

The term "trichothiodystrophy" (TTD) covers several autosomal recessive diseases whose diagnostic hallmark is short, brittle hair low in sulfur and cystine because of impaired synthesis of high-sulfur matrix protein. Clinical symptoms associated with TTD represent a variable range of abnormalities in organs derived from ectoderm and neuroectoderm. Important laboratory tests of the hair for the diagnosis of TTD comprise polarizing microscopy ("tiger-tail" pattern), electron microscopy, and amino acids analysis of hydrolyzed hair with a special focus on cystine. However, only very few institutions determine the amino acid composition of human hair and nail clippings, which requires special sample preparation including hydrolysis. If no special precautions are taken, quantification of cysteine and cystine becomes inaccurate because of decomposition of these residues during hydrolysis. We therefore performed the sample work-up with azide-dependent oxidation which we have for the first time adapted for analysis of hair and nail clippings. With our control and parent data resembling published data on hair and nail samples, we obtained a decreased proportion of cysteine (half cystine, determined as cysteic acid) in materials obtained from a boy with TTD. Clearly, the method for the quantification of cysteine following sodium azide-dependent oxidation is a suitable and rather convenient approach to the quantification of cyst(e)ine and other amino acids in hair and nail proteins, and is a valuable contribution to the diagnosis of TTD.

Cysteic Acid↗

PubMed2002

Delineation of the evolution of compositional changes in atheroma.

In a previous manuscript, we described a method combining immunohistochemistry, confocal scanning laser microscopy, and computer-assisted image analysis for the determination of the composition of atherosclerotic plaques [Taatjes et al. (2000) Histochemistry and Cell Biology 113:161-173). We now present an enhanced technique, and its use for age- and gender-related comparative analysis of lesion composition in ApoE knockout mice. Cryosections from aorta were stained with oil red O to detect lipid, SYTOX Green to detect cellularity, and Picrosirius red to delineate collagen fibers. The stained sections were imaged by brightfield light microscopy, epifluorescence microscopy, and polarized light microscopy. Digital images were collected, processed to isolate the lesions, and subjected to computer-assisted image analysis. The average percentage of the vessel wall occupied by lesion increased 1.5-fold in animals from 10 to 20 weeks. Although the amount of lipid in the lesions increased in animals from 10 to 20 weeks, the percentage composition in the lesion remained constant because of the increase in lesion size. Average cellularity showed a modest decrease over the same interval. However, the percentage composition of plaque attributable to collagen increased 2.5-fold in 20-week-old female animals compared with that in males or females of 10 weeks of age and males of 20 weeks of age.

Age Factors↗

PubMed2003

Amyloid in surgical pathology.

Amyloid is defined as a proteinaceous tissue deposit that shows a typical green birefringence in polarized light after staining with Congo red, the presence of non-branching linear fibrils of indefinite length with a mean diameter of 10 nm, and a distinct X-ray diffraction pattern consistent with Pauling's model of a cross beta-fibril. Amyloid may deposit locally or may present as a systemic disease. The origin of amyloid is diverse: 25 different fibril proteins have been described so far. The precursor proteins differ from each other in their primary structures and functions. The only common denominator is the propensity to form anti-parallel cross beta-fibrils under certain circumstances. Early diagnosis of amyloid is still a major challenge in surgical pathology. Histological proof can be obtained using Congo-red staining and polarization microscopy. However, small deposits may be difficult to discern, and sensitivity can be improved using fluorescence microscopy. Classification of amyloid is mandatory, since amyloid is treatable and different treatment regimens are applied to different amyloid diseases. This review focuses on the epidemiology, clinical features, pathology and diagnosis of amyloid in surgical pathology.

Amyloid↗

PubMed2000

Three-dimensional cartography of the pattern of the myofibres in the second trimester fetal human heart.

The aim of the present study was to describe the fibre architecture of the fetal heart at mid gestation, and to clarify some persistent controversies concerning the architecture of the myofibres in the right ventricular wall and the muscular ventricular septum. We used quantitative polarized light microscopy to obtain information about the orientation of myocardial cells in the ventricular mass. These cells, joined into a network by anastomoses, have at any point in the ventricular mass a principal direction--the fibre direction. We have quantitated this information in the form of maps of the azimuth and elevation angles, in 18 midgestation fetal hearts. Our findings show that the fibre architecture of the heart can be conceptualised as myocardial fibres running like geodesics on a nested set of warped "pretzels". This model is an extension to the whole ventricular mass of Krehl's Triebwerk, and Streeter's model which was restricted to the left ventricle. A "pretzel" itself can be considered as two doughnuts joined side-by-side, with the tunnel at the center of each doughnut corresponding to the ventricular cavity. Over and above the excellence of the fit between the data and the geodesic representation, three strong arguments support this model. First, it is the only existing model that explains the observed rolling over of fibres around the atrioventricular valvar orifices. Second, it explains the trajectory of the fibres from the epicardium to the endocardium at the basal parts of both ventricles and at the apical part of the left ventricle. Third, the predicted topological singularities of the model are systematically observed in each of the 18 hearts studied.

Gestational Age↗

PubMed2006

Improved abdominal wall wound healing by helium pneumoperitoneum.

BACKGROUND: Despite widespread use of the endoscopic technique in the treatment of inguinal and incisional hernias, knowledge about its impact on abdominal wall wound healing is rare. Questions remain regarding the risk of port-site hernias and hernia recurrence. The current study investigated the gas-dependent effects of pneumoperitoneum on laparotomy wound healing. METHODS: Laparotomy was performed in 54 male Sprague-Dawley rats. A carbon dioxide (n = 18) or helium (n = 18) pneumoperitoneum of 3 mmHg was maintained before and after laparotomy, with an overall duration of 30 min. The rats in the control group (n = 18) received no pneumoperitoneum. The animals were killed after 5 and 10 days, and the abdominal wall was explanted for subsequent histopathologic examinations of the laparotomy wound. The granuloma formation in hematoxylin and eosin-stained sections was analyzed. Infiltration of macrophages (CD68) and expression of matrix metalloproteinases (MMP-8 and MMP-13) were examined by immunohistochemistry. The collagen type 1 to type 3 ratio was investigated by cross-polarization microscopy after Sirius Red staining. RESULTS: After 5 and 10 days, the percentages of CD68-positive cells, granuloma formation, and expression of MMP-8 did not differ between the groups. In contrast, after both 5 and 10 days, the expression of MMP-13 and the collagen 1 to 3 ratio were significantly higher after helium pneumoperitoneum than in the control animals. CONCLUSION: The results suggest that helium pneumoperitoneum may ameliorate wound healing within the abdominal wall and could therefore represent a beneficial gas for endoscopic hernia repair.

Abdominal Wall↗

PubMed2004

Roles of microtubules and cellulose microfibril assembly in the localization of secondary-cell-wall deposition in developing tracheary elements.

The roles of cellulose microfibrils and cortical microtubules in establishing and maintaining the pattern of secondary-cell-wall deposition in tracheary elements were investigated with direct dyes to inhibit cellulose microfibril assembly and amiprophosmethyl to inhibit microtubule polymerization. When direct dyes were added to xylogenic cultures of Zinnia elegans L. mesophyll cells just before the onset of differentiation, the secondary cell wall was initially secreted as bands composed of discrete masses of stained material, consistent with immobilized sites of cellulose synthesis. The masses coalesced, forming truncated, sinuous or smeared thickenings, as secondary cell wall deposition continued. The absence of ordered cellulose microfibrils was confirmed by polarization microscopy and a lack of fluorescence dichroism as determined by laser scanning microscopy. Indirect immunofluorescence showed that cortical microtubules initially subtended the masses of dye-altered secondary cell wall material but soon became disorganized and disappeared. Although most of the secondary cell wall was deposited in the absence of subtending cortical microtubules in dye-treated cells, secretion remained confined to discrete regions of the plasma membrane. Examination of non-dye-treated cultures following application of microtubule inhibitors during various stages of secondary-cell-wall deposition revealed that the pattern became fixed at an early stage such that deposition remained localized in the absence of cortical microtubules. These observations indicate that cortical microtubules are required to establish, but not to maintain, patterned secondary-cell-wall deposition. Furthermore, cellulose microfibrils play a role in maintaining microtubule arrays and the integrity of the secondary-cell-wall bands during deposition.

Asteraceae↗

PubMed1998

Three-dimensional reconstruction of approximal subsurface caries lesions in deciduous molars.

The present study examines the three-dimensional (3D) morphology of early approximal subsurface enamel caries lesions and subjacent dentin reactions in deciduous molars. Twenty-three extracted primary molars were embedded in Technovit 9100 and serial sections were cut using a saw microtome. Forty approximal lesions were found and investigated using polarized light microscopy for the identification of the different zones of the caries lesion. These zones were then reconstructed three-dimensionally using computer-aided 3D reconstruction methods and the dimensions and volumes of the translucent zone, the body of the lesion, and the dentin lesion were calculated. The enamel demineralization index was defined as the ratio between the translucent zone and the body of the lesion, whereas the enamel-dentin demineralization index was defined as the volumetric ratio of the early dentin lesion to the body of the enamel lesion. The 3D reconstruction of the lesions showed extremely heterogeneous micromorphological features of zone profiles. In enamel lesions, the results demonstrated a decreasing enamel demineralization index with increasing size of the lesion, which indicates a high risk of further caries progression. The enamel-dentin demineralization index indicated, in 5 out of 17 dentin lesions, a high risk of further caries progression. Computer-assisted 3D reconstruction and volumetric assessment of initial caries lesions in deciduous molars represents a valuable methodology in pathogenesis studies, which may lead to a better clinical understanding of caries progression.

Dental Caries↗

PubMed2004

Comparative pathomorphological study of contractile myocardium under conditions of increased left and right ventricular afterload.

Structural changes in the myocardium under conditions of increased left and right ventricular afterload were studied using polarization microscopy and histological, histochemical, and stereological methods. Increased afterload not complicated by heart failure was characterized by low number of damaged cardiomyocytes (3.3-6.5%) and moderate structural changes in the ventricular myocardium (contractures of different severity). Increased afterload complicated by heart failure was characterized by high ratio of damaged cardiomyocytes (5.6-19.2%) and severe reversible (grade I and II contractures) and irreversible (grade III contractures and lump degradation of myofibrils) structural changes. Irreversible damage to most cardiomyocytes included plasmatic impregnation, which was most pronounced in the subendocardial layer of ventricles operating under conditions of increased afterload. Comparative study showed that increased left and right ventricular afterload induces similar pathomorphological changes in the contractile myocardium. Our results indicate that increased afterload to the right or left ventricle is accompanied by the development of stereotypical structural changes in the myocardium. Profound and severe disturbances can cause heart failure.

Animals↗

PubMed2006

Use of surfactants as plasticizers in preparing solid dispersions of poorly soluble API: stability testing of selected solid dispersions.

PURPOSE: The purpose of the study is to evaluate the effect of surfactant-plasticizers on the physical stability of amorphous drug in polymer matrices formed by hot melt extrusion. METHOD: Solid dispersions of a poorly soluble drug were prepared using PVP-K30, Plasdone-S630, and HPMC-E5 as the polymeric carriers and surfactants as plasticizers. The solid dispersions were produced by hot melt extrusion at temperatures 10 degrees C above and below the glass transition temperature (Tg) of the carrier polymers using a 16 mm-Haake Extruder. The surfactants tested in this study included Tween-80 and Docusate Sodium. The particle size of the extrudate was reduced to have mean of 100-200 micron. The physical stability of the solid dispersions produced was monitored at 30 degrees C/60% for six-months and at 60 degrees C/85% for two-months in open HDPE bottles. Modulated differential scanning calorimetry, polarized light microscopy, powder X-ray diffraction and dissolution testing was performed to assess the physical stability of solid dispersions upon stress testing. RESULTS: The dispersions containing HPMC-E5 were observed especially to be susceptible to physical instability under an accelerated stress conditions (60 degrees C/85%RH) of the solid dispersion. About 6% conversion of amorphous drug to crystalline form was observed. Consequently, the system exhibits similar degree of re-crystallization upon addition of the surfactant. However, under 30 degrees C/60%RH condition, the otherwise amorphous Drug-HPMC-E5 system has been destabilized by the addition of the surfactant. This effect is much more reduced in the extruded solid dispersions where polymeric carriers such as Plasdone S-603 and PVP-K30 (in addition to surfactants) are present. Furthermore, the drug release from the solid dispersions was unaffected at the stress conditions reported above. CONCLUSIONS: Possible reasons for the enhanced stability of the dispersions are due to the surfactants ability to lower the viscosity of the melt, increase the API solubility and homogeneity in the carrier polymer. In contrast, while it is possible for the surfactants to destabilize the system by lowering the Tg and increasing the water uptake, the study confirms that this effect is minimal. By and large, the surfactants appear to be promising plasticizers to produce solid dispersions by hot melt extrusion, in so doing improving dissolution rate without compromising the physical stability of the systems.

Calorimetry, Differential Scanning↗

PubMed2006

Pulmonary suture abscess with false-positive 18F-fluorodeoxyglucose positron emission scan mimicking lung cancer recurrence.

We present the case of a 57-year-old woman with pulmonary suture abscess. She had undergone right S3 segmentectomy for early lung adenocarcinoma 7 years before and right breast-conserving surgery for invasive ductal carcinoma 5 months previously, followed by irradiation plus endocrine therapy. Chest radiography and computed tomography revealed an irregular mass (3.5 cm in diameter) between the residual S1 segment and the middle lobe, neighboring the staple line of the segmentectomy. 18F-fluorodeoxyglucose uptake into the mass increased, seen by positron emission scans. Therefore, we could not rule out the possibility of local recurrence of lung cancer and resected it. Pathologically and microbiologically, the mass was a suture abscess arising around the nylon suture of the previous segmentectomy. This lesion was the result of a foreign-body reaction, as confirmed by polarized microscopy. Moreover, titanium staples at the segmentectomy and breast-conserving surgery may also have contributed to this condition.

Adenocarcinoma↗

PubMed1991

Stunned myocardium and myocardial collagen damage: differential effects of single and repeated occlusions.

It has been suggested that collagen loss and damage is responsible for the dysfunction seen in stunned myocardium. To test this hypothesis we compared collagen in canine hearts stunned by repeated occlusion with collagen in hearts stunned by a single occlusion. Regional contractile function was equally depressed in both groups: segment shortening at 1 hour after reperfusion averaged 37% +/- 9% versus 32% +/- 9% of preocclusion values in repeated and single occlusion models, respectively. Midmyocardial collagen content was not different in either single occlusion (10.5% +/- 0.4%) or repeated occlusion models (9.5% +/- 0.7%) when compared with nonischemic hearts (8.5 +/- 0.8%). Collagen damage, which was revealed with polarized light microscopy, was seen in 5 of 6 dogs after repeated occlusion but was not apparent after a single occlusion. Thus although both models of stunned myocardium produce similar dysfunction, there was no apparent collagen loss. Furthermore, collagen damage was only seen after repeated occlusion. Therefore it appears unlikely that collagen damage is a primary mechanism of stunned myocardium.

Animals↗

PubMed1988

Acyclovir-induced renal failure. Clinical course and histology.

Four patients with a chronic fatigue syndrome experienced five episodes of acute renal insufficiency associated with high-dose (500 mg/m2) intravenous acyclovir administered intravenously as one-hour infusions. Nephrotoxicity developed despite precautions to avoid volume contraction. Examination of the urinary sediment of three patients by polarizing microscopy showed birefringent needle-shaped crystals within leukocytes. In the most severely affected patient, a serum creatinine concentration of 8.6 mg/dl developed and the patient underwent percutaneous renal biopsy that revealed foci of interstitial inflammation without tubular necrosis. Urine, blood, and renal tissue levels of acyclovir were high. One patient was rechallenged with low-dose intravenous acyclovir and the four patients later received oral acyclovir, all without adverse effect. The combined data from these patients support crystalluria and obstructive nephropathy as a mechanism of acyclovir-induced renal failure in humans. This experience emphasizes the importance of maintaining adequate hydration during high-dose acyclovir therapy.

Acute Kidney Injury↗

PubMed1991

A histological and histometric study of the periosteum in mandibular ramal and condylar areas of the rabbit.

These structures were investigated with various histological stains and by polarization microscopy. The width of the periosteal layers was measured in nine ramal and condylar areas at five different ages (0, 2, 6, 12 and 30 weeks). The total periosteal width changed during growth, as did the absolute and relative thickness of its cellular and fibrous layers. The results suggest that in these areas periosteal tension may influence growth of the condylar cartilage, and that this may vary during growth.

Aging↗

PubMed1976

The thermal transitions and structural properties of 5alpha-cholestan-3beta-ol esters of aliphatic acids.

5 alpha-Cholestan-3 beta-ol esters of aliphatic acids undergo both enantiotropic and monotropic changes of state. Ten saturated and three unsaturated esters have been examined by differential scanning calorimetry and polarizing microscopy to determine transition temperatures, enthalpies, and entropies. The results are compared with an analogous series of cholesterol esters. All esters of even-numbered n-alkanoic acids from C2 to C20 melt from a crystalline state to an isotropic liquid. The crystalline state has been studied by X-ray powder diffraction. The C8 to C20 esters have progressively increasing crystalline melting transition temperatures from 76 to 99 degrees C and possess similar X-ray powder diffraction patterns, suggesting that these compounds form an isostructural series. Esters of C2, C4, and C6 acids exhibit polymorphism. Crystalline cholestanol oleate melts to an isotropic liquid, whereas cholestanol linoleate and linolenate fail to crystallize, even after several months at -20 degrees C. Esters of the even-numbered saturated acids from C4 to C14 form monotropic cholesteric liquid crystalline phases. Esters C10, C12, and C14 form smectic liquid crystalline phases. Cholestanol oleate, linoleate, and linolenate form both cholesteric and smectic mesophases. The lower smectic to cholesteric and cholesteric to isotropic transition temperatures of the cholestanol esters compared to the corresponding transition temperatures of the analogous cholesterol esters suggest that the delta 5 double bond in cholesterol increases the thermal stability of the mesophases of cholesterol esters.

Binding Sites↗

PubMed1995

Influence of bile salt molecular species on cholesterol crystallization from supersaturated model biles.

Time-sequential enzymatic determination of cholesterol (CH) crystals harvested by ultrafiltration, and concomitant polarizing light microscopy observations corroborated the striking importance of the bile salts (BS) species in determining CH crystals formation rate from supersaturated model biles incubated in vitro. The more hydrophilic tauroursodeoxycholate, taurohyocholate, glycohyocholate, taurohyodeoxycholate, glycohyodeoxycholate and glyco-3 alpha, hydroxy-6 oxo-5 beta-cholanate inhibited CH precipitation through the formation of a stabilized liquid-crystalline phase. In contrast, in all hydrophobic systems (taurine (T) and glycine (G) conjugates of cholate (C), deoxycholate (DC) and chenodeoxycholate (CDC)), CH crystals precipitated with time. When crystallized CH concentrations were plotted vs. time, the figures showed a sigmoidal pattern, consistent with the transition from metastable systems to stable equilibrium states. Over the equilibration period, the nucleation kinetics (as inferred from enzymatic measurements) and all crystallization events (as microscopically observed) were both shifted in time, depending on the BS species: they were earliest in CDC systems, then in DC systems, and finally in C systems. In the latter, the delay was clearly due to the formation of a transient labile liquid-crystalline phase. G-conjugation also induced a significant delay in CH precipitation, compared to T-conjugation. At last, maximum crystallized CH concentrations at equilibrium were in the decreasing order: C > CDC > DC and T-conjugates > G-homologues. All data are discussed in connection with BS hydrophobicities, with predictions from the phase equilibria of aqueous biliary lipid systems and with new insights into CH crystal habits.

Bile↗