Thyroxine binding properties of glycosylated human serum albumin as measured by fluorescence

Thyroid hormone, thyroxine (T4) binding to glycosylated human serum albumin (G-HSA), and native human serum albumin (HSA) were studied as a function of pH using the fluorescence method. T4 binding affinity for G-HSA was remarkably reduced in an alkaline pH as compared with the native HSA. The thermodynamic parameters for binding are estimated at pH 7.5: (a) for G-HSA, delta G = -8.50 +/- 0.04 kcal mol-1 (30 degrees C), delta H = -5.2 kcal mol-1, delta S = +11 e.u.; (b) for HSA, delta G = -8.89 +/- 0.04 kcal mol-1 (30 degrees C), delta H = -3.5 kcal mol-1, delta S = +18 e.u. These results suggest that the glycosylation of HSA causes a variation in the electrostatic interaction between T4 and HSA.

Drug binding properties of glycosylated bovine serum albumin as measured by circular dichroism

The binding properties of Sudlow's site-specific drugs to glycosylated bovine serum albumin (G-BSA) (1.25 mol glucose per mol of albumin) have been investigated using the circular dichroism (CD) method. Site I-specific drugs, phenylbutazone and warfarin, and site II-specific drugs, flufenamic acid and ibuprofen, were used. The induced ellipticities of phenylbutazone, flufenamic acid and ibuprofen-G-BSA complexes diminished and those of warfarin complex were enhanced in comparison with those for the intact bovine serum albumin (BSA) complexes. These CD change suggests that the glycosylation of BSA at the primary modification site influences the binding properties of the site-specific drugs to serum albumin.

Immunological studies on Crohn's disease. X. Conclusion: a new tentative hypothesis

Although much progress has been made in understanding the pathogenesis of Crohn's disease, the precise etiology of Crohn's disease still remains unknown. In our serial studies on Crohn's disease, we found a decrease in NK and ADCC activities as well as a decrease in the phagocytic activity by monocytes, whereas an increased superoxide production activity by monocytes was evident. On the other hand, the characterization of lymphocyte subpopulations has demonstrated no abnormalities. According to these findings, we would like to propose a new tentative hypothesis for the pathogenesis of Crohn's disease. It has been suggested that impaired killing system activities, such as phagocytic activity as well as NK and ADCC activities, are primarily responsible for the promotion and perpetuation of chronic inflammation and ulceration. When our attention is directed to the most common target substances of these protective mechanisms, viral antigens appear as the most likely causative organism. Therefore, a lot of attention has been focused on viral infection as a causative factor. Furthermore, based on this hypothesis, strategies for effective treatment of this disease are also discussed.

Clinical course and long-term prognosis of Crohn's disease in Japan

The long-term outcome of Crohn's disease was reviewed in 74 patients who had a history of more than 10 years (range 10.8-27.3) since disease onset. The observation period was between 4.3 and 18.5 years, the mean and SD being 10.6 +/- 3.1 years. The means and SD of age at onset and final observation were 21 +/- 7 and 37 +/- 8 years, respectively. Fifty-eight of the 74 patients had not undergone bowel resection at the time of diagnosis; of these 58, 31 (53.4%) had an operation for the disease during the follow-up period. Thus, of the 74 patients, 47 (63.5%) (these 31, plus the 16 who had undergone bowel resection at the time of diagnosis) had an operation at least once during a follow-up period of 10 years or more. The cumulative operation rates 5, 10, and 15 years after onset in the 74 and 58 patients above were 18.9%, 6.9%, and 40.8%, and 34.8%, 49.1%, and 46.0%, respectively. The corresponding figures 5 and 10 years after diagnosis in all 74 patients and the 58 patients were 32.3% and 28.6% and 47.3% and 46.3%, respectively. There were no significant differences in the incidence of operation rate in relation to anatomical involvement. Cumulative reoperation rates 1, 3, 5, and 10 years after the first operation in the 31 patients who were operated on during the follow-up period were 3.4%, 6.9%, 25.5%, and 51.7%, respectively. Three patients died, the causes of death in one being directly related to Crohn's disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of guanidine hydrochloride on the conformation of egg yolk low density lipoprotein

The denaturation of egg yolk low-density lipoprotein (LDL) induced by guanidine hydrochloride (GdnHCl) has been investigated by using circular dichroism (CD) and fluorescence measurements. The transition curves were obtained from changes of the residue ellipticity at 222 nm and the fluorescence intensity of the aromatic residues, tyrosine and fluorescence. Different transition curves were obtained at the molarities of GdnHCl between 2 and 6 M, and between 1 and 4 M from the CD and the fluorescence measurements, respectively. The noncoincidence of the transition curves as well as the asymmetry of the transition curve obtained from the fluorescence measurements suggests that the denaturation process of LDL consists of several transition states. A very low apparent free energy of denaturation (delta G(app) H2O = 3.0 kcal mol-1) obtained by CD data suggests that LDL has an unstable folded structure in its native state.

A case of cytomegalovirus mononucleosis associated with pleural effusion

A 5 year old boy had a spiky fever accompanied by a mild pharyngitis, cervical lymphadenopathy and hepatosplenomegaly. Laboratory findings revealed leukocytosis with 26% atypical lymphocytes, and liver dysfunction. A chest X-ray showed pneumonia and a considerable amount of pleural effusion. Serum antibody titers for cytomegalovirus (CMV) were elevated significantly and CMV-DNA (polymerase chain reaction) was detected in the pleural effusion. Only 13 cases of pleural effusion associated with infectious mononucleosis have been reported previously in the literature, but there was no documentation that proved CMV infection. The case reported here suggests that the pleural effusion was caused by the infiltration of mononuclear cells to the pleura as a result of systemic inflammation, and the possible alternative of host immune response against CMV was related to recent Varicella zoster virus infection.

Drug binding properties of glycosylated human serum albumin as measured by fluorescence and circular dichroism

Binding properties of Sudlow's site-specific drugs to glycosylated human serum albumin (G-HSA) were investigated using fluorescence and circular dichroism (CD). Dansylamide, phenylbutazone and warfarin were used as site I-specific drugs, and dansylproline, ibuprofen and flufenamic acid were used as site II-specific ones. Similar changes in the fluorescence intensity of dansylamide occurred in the presence of both G-HSA and intact human serum albumin (HSA), while the fluorescence enhancement of dansylproline caused by G-HSA was extremely weakened in comparison with that by HSA. These results suggest that the glycosylation of HSA inhibits the binding of the site II-specific drug, dansylproline, to HSA, while it does not influence the binding of the site I specific drug, dansylamide. The induced ellipticities of the complexes of ibuprofen, flufenamic acid and phenyl butazone with G-HSA were diminished in comparison with those with HSA. With the complexes of warfarin, the induced ellipticity was enhanced. These CD results suggest that the glycosylation of HSA induces microenvironmental changes in the binding sites for the above site-specific drugs which influence the drug binding ability of HSA.

Thoracoscopic pulmonary resection in two cases using an endoscopic linear stapler and loop ligature

Recent advances in rigid endoscopic imaging capabilities, light sources, and instrumentation have dramatically expanded the potential role of laparoscopic and thoracoscopic surgery. Moreover, the recent introduction of an endoscopic linear stapling device and loop ligature has made thoracoscopic pulmonary resection possible. We present herein two cases of peripheral pulmonary lesions which were resected thoracoscopically. Case 1 was a 19-year-old man with a history of recurrent pneumothorax due to a left apical bulla who underwent thoracoscopic lung resection using a new stapling device, and Case 2 was a 46-year-old man with a small pulmonary lesion on the left basal segment (S8) who underwent thoracoscopic lung resection using loop ligature. Postoperatively, there was no evidence of air leak in either patient and both were discharged 6 days after surgery. The technical procedures for thoracoscopic lung resection and the clinical courses of both patients are described in this paper.

[A study on the detection of Helicobacter pylori in children with gastric and duodenal diseases]

Infection of Hellcobacter pylori (H. pylori) in the gastric mucosa is said to participate in the pathogenesis of gastric and duodenal ulcers as well as gastritis. The detection rate of H. pylori in tissue specimens endoscopically taken from adult patients with these diseases was 75.2% (408/542). In affected children (2-15 yrs), on the other hand, 27 biopsies were performed in 22 cases but the initial positive rats was as low as 45.5%. According to the diagnosis, it was 75% for acute gastric mucosal lesion (AGML), 50% for duodenal ulcer, 33% for duodenitis, and 38% in seemingly normal children. When changes in the detection rate of H. pylori was examined after administration of H2 blocking antiulcer agents, it was found to very case by case, e.g. changed in individual disease stages or completely or reoccurrence disappeared.

Effect of divalent metal ions on the binding of thyroxine to bovine serum albumin as measured by fluorescence

The binding of thyroxine (T4) to bovine serum albumin (BSA) has been studied in the presence and absence of Ca2+, Cu2+ and Zn2+ ions at various pH's in 0.1 M Tris-acetate buffer at 25 degrees C using the fluorescence method. In the presence of 50 microM Ca2+ and Zn2+ and the absence of metal ions, the binding constant (K) increased similarly with increasing pH values from pH 5 to pH 9, and the K value near midpoint, pH 7.4, was 1.66 +/- 0.17 x 10(6) M-1. By contrast, the binding constant remained constant between pH5 and pH9 in the presence of 10 microM Cu2+, with an average value of 1.61 +/- 0.22 x 10(6) M-1, suggesting a significant influence of Cu2+ ions on T4 binding to BSA.

Effect of inorganic anions on the binding of thyroxine by bovine serum albumin

The fluorescence method was used to investigate the effect of inorganic anions, SCN-, I-, ClO4- and Br- on the binding of thyroxine (T4) by bovine serum albumin (BSA). The apparent binding constants were evaluated in 0.1M sodium phosphate buffer, pH 7.4 at 25 degrees C containing various concentrations of the anions up to 0.15M. Their values decreased at high anion concentrations. The effectiveness of anions in reducing T4 binding was in the following order: SCN- > I= > ClO4- > Br-. Thermodynamic parameters determined in the presence of 0.1M SCN- suggested that the hydrophobic interaction between T4 and BSA could be reduced by these inorganic anions.

Thyroxine binding properties of glycosylated bovine serum albumin

Thyroid hormone, thyroxine (T4) binding properties of glycosylated bovine serum albumin (G-BSA), and intact BSA were studied by the fluorescence method. The apparent binding constants for intact BSA were 0.8 (0.16) x 10(6) M-1 at pH 5.0 and 2.18 (0.06) x 10(6) M-1 at pH 9.5 at 25 degrees C. T4 binding for G-BSA was independent of pH and the apparent binding constant was 1.4 x 10(6) M-1. Thermodynamic parameters were also evaluated from the Van't Hoff plots of the apparent binding constants at pH 7.4 and 8.5. At both pH's, the free energy, enthalpy and entropy changes were almost the same for both G-BSA and BSA.