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1.
Patients with chronic hepatitis C, with a high serum viral load (> or = 1 Meq/ml) and genotype 1b seem to be resistant to interferon (IFN) therapy. To evaluate the efficacy of a herbal medicine (Mao-to) in combination with natural IFN-beta for the treatment of these patients, eighteen Japanese patients were enrolled in this study. Every patient received 6 million units (MU) of IFN-beta intravenously daily for 8 weeks. Mao-to was given orally 3-4 times a day during the IFN-beta administration, Sixteen of the 18 patients (89%) became negative for serum HCV RNA at the end of treatment, but only 2 of them (11%) remained negative for the virus RNA at 6 months of follow-up. Serum ALT levels normalized in 17 patients (94%) at 2 weeks of follow-up after the cessation of therapy, and 11 patients (61%) retained normal ALT levels for more than 6 months of follow-up. This rate of biochemical response was high as compared with that of therapy with IFN-beta alone (19%) in the largest IFN-beta trial in Japan. Serum hyaluronic acid levels were decreased significantly from 147.0 +/- 110.5 ng/ml to 77.4 +/- 67.4 ng/ml in the sustained biochemical response group (P = 0.003). None of the patients needed to interrupt therapy because of side effects of IFN-beta. Thus, Mao-to administration together with IFN-beta treatment could increase the sustained biochemical response rate, and reduce liver fibrosis.  相似文献   
2.
From a suspension of mouse spleen cells were separated two functionally different cell types on the basis of their ability or inability to adhere to plastic dishes during a short period of incubation. Morphological observations of cells of these two fractions were made with the aid of histochemical methods. The majority of cells in the adherent fraction possessed β-glucuronidase, which is one of the lysosomal enzymes rich in macrophages or phagocytic cells. In contrast, almost all cells in the non-adherent fraction were devoid of this enzyme activity and identified morphologically as small lymphocytes. The adherent and non-adherent cells were found to associate in cell clusters during the cultivation. In the cultures stimulated with sheep red blood cells, some of the non-adherent cells which were located peripherically in the cell clusters began to show alkaline phosphatase activity in their cytoplasm. This may perhaps indicate that antibody synthesis is going on in these alkaline phosphatase-positive cells, since in an in vivo study such cells were found to arise in the lymph nodes of immunized animals concomitantly with the appearance of specific serum antibody.  相似文献   
3.
Effects of fatty acids on Ca2+-ATPase and Mg2+-ATPase in the microsomal fraction of rat submandibular gland have been investigated. Saturated fatty acids had almost no effect, but unsaturated fatty acids inhibited both ATPases. Modes of inhibition by linoleic acid were as follows: competitive for calcium and ATP with Ca2+-ATPase; non-competitive for magnesium and ATP with Mg2+-ATPase  相似文献   
4.
Phosphorylation of Ser180 in cytoplasmic loop D has been shown to reduce the water permeability of aquaporin (AQP) 4, the predominant water channel in the brain. However, when the structure of the S180D mutant (AQP4M23S180D), which was generated to mimic phosphorylated Ser180, was determined to 2.8 Å resolution using electron diffraction patterns, it showed no significant differences from the structure of the wild-type channel. High-resolution density maps usually do not resolve protein regions that are only partially ordered, but these can sometimes be seen in lower-resolution density maps calculated from electron micrographs. We therefore used images of two-dimensional crystals and determined the structure of AQP4M23S180D at 10 Å resolution. The features of the 10-Å density map are consistent with those of the previously determined atomic model; in particular, there were no indications of any obstruction near the cytoplasmic pore entrance. In addition, water conductance measurements, both in vitro and in vivo, show the same water permeability for wild-type and mutant AQP4M23, suggesting that the S180D mutation neither reduces water conduction through a conformational change nor reduces water conduction by interacting with a protein that would obstruct the cytoplasmic channel entrance. Finally, the 10-Å map shows a cytoplasmic density in between four adjacent tetramers that most likely represents the association of four N termini. This finding supports the critical role of the N terminus of AQP4 in the stabilization of orthogonal arrays, as well as their interference through lipid modification of cysteine residues in the longer N-terminal isoform.  相似文献   
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6-Hydroxymellein (6HM) synthase is a multifunctional polyketide enzyme induced in carrot cells, whose fully active homodimer catalyzes condensation of acyl-CoAs and the NADPH-dependent ketoreduction of the enzyme-bound intermediate. 6HM-forming activity of the synthase was markedly decreased when the reaction mixture pH was adjusted from 7.5 to 6.0. However, under these slightly acidic conditions, the acyl condensation catalyzed by the dissociated monomer enzyme was appreciably stimulated by addition of free coenzyme A (CoA). In contrast, the condensation reaction at pH 6.0 was significantly inhibited in the presence of CoA when the reaction was carried out with the NADPH-omitted dimer synthase. Among the kinetic parameters of the acyl condensation, velocity of the monomer-catalyzing reaction at the acidic pH was appreciably increased upon addition of CoA while K(m)s did not show any significant change in the presence and absence of the compound. These results suggest that CoA associates with a specific site in the dissociated monomeric form of 6HM synthase, and the velocity of the acyl condensation reaction catalyzed by the CoA-synthase complex appreciably increases in acidic conditions.  相似文献   
8.
At an ambient temperature of 34-41 degrees C (rh = 40%) forearm sweat rates were measured by capacitance hygrometry in 9 male volunteers. Thyrotropin releasing hormone (TRH) was infused intravenously at 0.1 mg.min-1 for 20 to 30 min. Sweat rate increased rapidly within a minute after initiation of TRH infusion, decreased rapidly after the peak sweat rate was attained in 2-5 min of TRH infusion, and then levelled off in 6-10 min near the level before TRH infusion. Core temperature (Tre, Tty) started to decline at the time of the peak sweat rate and levelled off almost coincidentally with the levelling off in sweat rate. Average values for the rate of sweat expulsions (Fsw), sweat rate and mean body temperature (Tb) were obtained from the data of the last 10 min period of TRH infusion. The regression line for the relationship of Fsw to Tb shifted during the TRH infusion to the left of the line for the control; that of sweat rate to Fsw hardly shifted. At an ambient temperature of 24-27 degrees C TRH produced vasodilation as evidenced by an increase in skin blood flow (measured by means of thermal distribution), an increase in amplitude of the photoelectric plethysmogram and an elevation of skin temperature in the finger tips. It is suggested that TRH may act, either directly or indirectly, on the central thermoregulatory mechanism (or on the thermoreceptive mechanism) to lower the reference temperature for heat dissipation.  相似文献   
9.
We have used human β2 and β4 cDNA probes to map the genes encoding two isoforms of the regulatory β subunit of voltage-activated Ca2+ channels, viz. CACNB2 (β2) and CACNB4 (β4), to human chromosomes 10p12 and 2q22-q23, respectively, by fluorescence in situ hybridization. The gene encoding the β2 protein, first described as a Lambert-Eaton myasthenic syndrome (LEMS) antigen in humans, is found close to a region that undergoes chromosome rearrangements in small cell lung cancer, which occurs in association with LEMS. CACNB2 (β2) and CACNB4 (β4) genes are members of the ion-channel gene superfamily and it should now be possible to examine their loci by linkage analysis of ion-channel-related disorders. To date, no such disease-related gene has been assigned to 10p12 and 2q22-q23. Received: 5 February 1997 / Accepted: 4 April 1997  相似文献   
10.
Abstract: Laminin A, B1, and B2 chain mRNA levels in degenerating and regenerating mouse sciatic nerves were examined using northern blot analysis. In normal intact nerves, B1 and B2 mRNA steady-state levels were high, but when the nerves were crushed, the steady-state levels of B1 and B2 mRNA per milligram wet tissue weight of the distal segments of the nerves increased five- to eightfold over that of control levels as the total RNA and β-actin mRNA levels increased, suggesting that these increases were the consequence of Schwann cell proliferation after axotomy. When the steady-state levels of B1 and B2 mRNA were normalized as the ratio to total RNA or β-actin mRNA levels, however, they drastically decreased to about 20% of the normal nerve levels in the nerve segments distal to both the crush and transaction sites 1 day after injury. In the crushed nerves, B1 and B2 mRNA levels gradually increased as the regenerating nerves arrived at the distal segments and reestablished normal axon–Schwann cell contact, and then returned to normal levels on the 21 st day. In the transected nerves, where Schwann cells continued to be disconnected from axons, both B1 and B2 mRNA levels remained low. Cultured Schwann cells expressed detectable levels of B1 and B2 chain mRNA which significantly increased when the cells were cocultured with sensory neurons. However, mRNA for A chain was not detectable in the normal, axotomized nerves or in cultured Schwann cells. These data indicate that Schwann cells express laminin B1 and B2 chain mRNA that are up-regulated by axonal or neuronal contact, but they do not express A chain mRNA.  相似文献   
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