Glycosaminoglycans in dialysis-related amyloidosis.
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Biomedical subjects
Publications and source records attributed to Z Cai.
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Effects of intrauterine hypoxia-ischemia (HI) on brain functional development in the term rat were examined in cerebellar granule cell cultures obtained from an in utero HI model. On gestation d 17, HI conditions were achieved by complete clamping of the uterine vasculature for designated durations followed by removal of the clamps to permit reperfusion. Sham operation (surgery without vasculature clamping) was performed as the control. After surgery, the uterine horns were returned to dam's abdomen to let the pups deliver naturally. Severe HI insult from the surgical manipulation was evident in that the lactate levels of fetal brain increased, and fetal blood pH decreased with the duration of vasculature clamping up to 1 h. The experimental HI insult up to 1 h did not affect fetal survival rate, but retarded growth of fetuses or newborns was observed in the 1 h HI group. N-Methyl-D-aspartate (NMDA)- and kainate (KA)-stimulated cGMP formation and glutamate accumulation were measured in cerebellar granule cell cultures from 8-d-old pups suffering from various durations of antenatal HI insult. NMDA (100 microM)-induced elevation of cGMP was further augmented by a 10-35-min HI insult as compared with the control cells (62.4-78.2 versus 49 pmol/mg protein). In the presence of L-NG-monomethyl-arginine (L-NMMA, 150 microM), a nitric oxide synthase inhibitor, NMDA-induced cGMP formation was blocked, and the blockade of cGMP formation by L-NMMA (10 microM) could be reversed by simultaneous application of 1 mM arginine in both control and HI cells.(ABSTRACT TRUNCATED AT 250 WORDS)
The reaction of OH radicals with baicalin was studied by pulse and gamma radiolysis in N2O-saturated aqueous solutions. The addition of an OH radical to baicalin produced an intermediate species that shows a maximum UV absorbance band at 420 nm and decays with a unimolecular rate constant of 1.25 x 10(4) s-1 and a bimolecular rate constant of 6.1 x 10(8) mol-1 dm3 s-1. Four major final products were obtained by gamma irradiation, and their structures were identified. Two of them (P1 and P2) are suggested to originate from the unimolecular reaction and the other two (P3 and P4) from the bimolecular reaction of the radicals.
The fundus and retinal ultrastructural changes of rats with hypertension and such rats having taken life-long captopril treatment were examined by funduscope, light and transmission electron microscopes. The normal rats were the controls. The results showed that in the hypertension group, the ratio of the diameter of the retinal artery to that of the vein was 1:2, the arteries were spastic and narrowed, their light reflexes were widened and their calibers of the lumens were uneven, the fundus appearances being consistent with grade I and II retinal changes of systemic hypertension. Under the light microscope, it was discovered that the basement membranes of the retinal capillaries were thickened and their lumens narrowed, resulting in retinal ischemia and anoxia. Under the transmission electron microscope, the main pathological changes involved the external segments of photoreceptors and ganglionic cells. The pathological changes were hazy renewed membranous discs at the basal portions of the external segments of photoreceptors, edematous ganglionic cells being the majority, their cytoplasm stained pale, mitochondrial vacuolization, enlargement of smooth endoplasmic reticula and degranulation of rough endoplasmic reticula. In the group of rats with hypertension having taken life-long captopril treatment, the fundi and blood pressure remained normal and no significant ultrastructural changes had taken place in their retinae.
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Hearing loss and CT findings of 200 ears from 102 cases with congenital malformation of inner ear were included in our study. Hearing loss was typically bilateral severe, or total deafness. 75 percent of them were found deaf within one-year-old. In addition, 47 patients' (46%) mothers were noted to have caught a cold in first trimester of pregnancy. Temporal bone abnormalties were described as five types: 1. Michel malformation, 2. Mondini malformation, 3. enlargement of the vestibular aqueducts, 4. developmental deformity of cochlear aqueduct, 5. developmental deformity of internal acoustic meatus. Most cases showed malformations of vestibule or vestibular aqueducts.
The single channel features of inward rectifier potassium current (IK1) in primary cultured embryonic chick ventricular myocytes and the effect of culture time on it were studied by using cell-attached patch clamp technique. The results showed that inward current fluctuation could be recorded at membrane potential negative to the potassium equilibrium potential (EK) and [K+] o = [K+]i = 140 mmol/L. The single channel current-voltage (I-V) relation was linear. The slope conductance was 35 pS (1-3 day culture). But at membrane potential positive to the EK, strong inward rectification was evident. The analysis of open and close time distribution indicated that a close-close-open three state model was appropriate to describe the gating processes of IK1 channel. No significant effect of culture time was observed. The channel density and slope conductance of IK1 were 0.64, 0.76, 0.77 channels/microns and 35, 28, 37 pS corresponding to 1-3, 4-6, and 7-11 day culture period, respectively. This result could partially explain why action potential of cardiomyocytes did not change with culture time.
The effects of inclusion on Pericarpium Citri Reticulatae volatile oil-beta-cyclodextrin were studied by comparing four methods saturation, grinding, liquid to liquid and liquid to gas. The utilization ratio of oil, the ratio of oil in inclusion complex and the recovery of inclusion complex were used as the criteria in evaluating the inclusion effectiveness. The results showed that the saturation method was the best.
Correlative study of CT, MRI and pathology was done on 121 cases with solitary pulmonary nodule less than 3 cm in diameter, including 97 malignant nodules and 24 tuberculoma. On CT, the main morphological characteristics of the malignant nodules is lobucation, spiculation, vessele involvement, heterogeneous density, and vacuole sign and air bronchogram, and that of the tuberculoma, the smooth margin, homogeneous density, calcification. On the other hand, the relative signal intensity of these pulmonary nodules were evaluated on T1, T2 weighted image. Our prelminary results indicated that though MRI is inferior to CT in the assessment of the margin and internal feature of the nodule, it can provide further information in differentiating between malignant nodule and tuberculoma.
The fibrinolytic activity status of the patients with cerebral infarction can affect their clinical prognosis. In this case-controlled study, the plasma fibrinolytic system activities in 30 cases of cortical artery territory cerebral infarction (CACI) and 32 cases of perforating artery territory cerebral infarction (PACI) with a disease duration less than 3 days were assayed with a comprehensive panel including the plasma tPA activity, PAI activity, tPA releasing capacity from vascular endothelium and PAI/tPA ratio values. 30 subjects without cardiovascular and cerebrovascular disorders were served as control. The results showed that the plasma fibrinolytic system activities of the patients with aforementioned two subtypes of cerebral infarction were significantly lower than those of the controls, the results provide a theoretical basis for carrying out thrombolytic therapy in patients with ischemic stroke and suggest that recurrent cerebral infarction might be related to the high activity of plasma PAI.
The crystal structure of hexon, the major coat protein from adenovirus type 2, has been refined at 2.9 A resolution. Hexon is a homo-trimer (molecular mass 3 x 109,077 Da) and crystallizes in the cubic space group P2(1)3, with a cell edge of 150.5 A. There are four molecules in the unit cell so that the crystallographic asymmetric unit contains one subunit of the trimer. The electron density in most regions is well-defined and 880 amino acid residues, of the 967 in this unusually long polypeptide chain, have been located and fitted. The N terminus (1 to 43) and three internal stretches (192 to 203, 270 to 291 and 444 to 453) are not defined, and a stretch (168 to 207) with unclear side-chain density is modelled as poly(Ala/Gly). The current refined model, consisting of 6943 non-hydrogen protein atoms and 85 water molecules, yields an R-factor of 19.9% for 18,176 reflections in the resolution range 5.0 to 2.9 A. The model has reasonable geometry with root-mean-square deviations from ideal bond lengths of 0.022 A and angle-related 1-3 distances of 0.056 A. The overall shape of the trimeric hexon molecule is unusual and may be divided into a pseudo-hexagonal base rich in beta-structure, and a triangular top formed from three long loops containing some secondary structure. The base contains two similar pedestal domains, P1 and P2, each of which is a flattened eight-stranded beta-barrel with the "jelly-roll greek key" topology characteristic of other viral coat proteins. P1 and P2 are related by an approximate 6-fold operation about the molecular 3-fold axis so that six barrels form the walls of the tubular hexon base. The hexon bases form close-packed p3 arrays on each facet of the icosahedral adenovirus virion. Unlike other viral capsids, the barrel axes are almost perpendicular to rather than parallel with the capsid surface. The hexon top, which consists of intimately interacting loops emerging from P1 and P2 in the base, has a triangular outline and so does not exhibit the pseudo-symmetry of the base. The structure of the hexon trimer shows how economically it meets the demands of its function as a stable protective viral coat, reveals the significance of the special features in its unusual amino acid sequence, and explains its biochemical and immunological properties. The molecule is hollow, with a large central cavity, and so has a high effective volume for its mass.(ABSTRACT TRUNCATED AT 400 WORDS)
We have previously reported a new spontaneous recessive mutation that induces a generalized lack of lymph nodes (LNs) and Peyer's patches (PPs) accompanied by immunodeficiency in mice (gene symbol, aly). In this study, we have analyzed gut-associated lymphatic tissues of the mutant aly/aly mice and have compared the intestinal intraepithelial T lymphocytes (IEL) in aly/aly and normal aly/+ littermate mice. Immunohistochemical studies revealed that colonization of IEL and lamina propria T cells takes place in the absence of PPs and IgA-producing B cells in the lamina propria. Absolute numbers of Thy-1- IEL-alpha beta and -gamma delta are not altered in aly/aly mutant mice, whereas absolute numbers of Thy-1+ IEL-alpha beta and -gamma delta in aly/aly mice are about half of those in aly/+ mice. In IEL-alpha beta from aly/aly mice, the major CD8 alpha alpha+ and CD8 alpha beta+ subsets are maintained, whereas CD4+ and CD4+, CD8+ subsets are reduced. Although the population size of major CD8 alpha alpha+ and CD4-, CD8- IEL-gamma delta subsets is slightly reduced, the use of TCR-gamma- and -delta-chain variable gene segments by IEL-gamma delta remains almost the same in aly/aly mice. The constitutive cytolytic activity of IEL-alpha beta and -gamma delta is attenuated sharply in the aly/aly condition. This activity is, however, augmented significantly after in vitro stimulation with anti-CD3 mAb. These results indicate that most of the IEL subpopulations develop independently of passage through PPs and mesenteric LNs and that the aly mutation interrupts cytotoxic IEL development during relatively late differentiation steps that convert cytotoxic precursors to the constitutively cytolytic state.
Clonotype-positive (1B2+) T cells from 2C T cell receptor (TCR) transgenic mice were used to define the role of CD8 molecules in the induction phase vs. the effector phase of the primary response to class I alloantigens. Three main findings are reported. First, in the presence of exogenous lymphokines, resting CD8+ 2C cells gave strong proliferative responses to two alloantigens, Ld and Kbm11. In the absence of added lymphokines, however, CD8+ 2C cells responded only to Ld and not to Kbm11; Ld stimulated both interleukin 2 (IL-2) and IL-2 receptor (R) synthesis, whereas Kbm11 elicited only IL-2R synthesis. The primary response of CD8+ 2C cells was thus helper-independent (HI) to Ld but helper-dependent (HD) to Kbm11, presumably reflecting that Ld is a stronger antigen than Kbm11. Second, in contrast to CD8+ cells, CD8- 2C cells mounted only an HD and not an HI response to the strong Ld antigen; conversely, selecting for a minor subset of CD8hi cells enabled 2C cells to mount an HI response to the weak Kbm11 antigen. These findings, together with experiments with heterozygous vs. homozygous stimulator cells, suggest that HI and HD responses reflect differences in the overall avidity of T antigen presenting cell (APC) interaction: high-avidity interaction leads to strong intracellular signaling and an HI response, whereas low-avidity interaction causes weak signaling and an HD response; high-avidity T/APC interaction is heavily dependent on CD8 expression. Third, CD8 expression was found to be less important for CTL activity than for primary proliferative responses. Thus, in contrast to HI proliferative responses, CTL responses of 2C cells to Ld were CD8 independent. However, 2C lysis of Ld targets became strongly CD8 dependent in the presence of limiting doses of anti-TCR (1B2) antibody. Collectively, the data suggest that, both for T cell induction and the expression of effector function, CD8 molecules play a decisive role in augmenting TCR-mediated signaling, either by promoting TCR contact with antigen or delivering kinases (p56lck) to the TCR/CD3 complex, or both.
Prenatal ethanol exposure-induced alteration in poly-phosphoinositide (PPI) hydrolysis stimulated by excitatory amino acids (EAA) was studied in rat cerebellar granule cells previously labeled with [3H]myoinositol. The prenatal exposure to ethanol was achieved via maternal consumption of a Sustacal (chocolate flavored) liquid diet containing either 5% ethanol (w/v, 35% of calories) or isocaloric sucrose (pair-fed) substituted for ethanol from gestation d 11 until the day of parturition. The ionotropic glutamate receptor agonists, N-methyl-D-aspartate, kainate or (+/-)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) (100 microM each) induced a two- to four-fold increase in PPI hydrolysis over the basal level, regardless of the liquid dietary treatment. Stimulation with quisqualate (QA), an agonist activating both metabotropic and ionotropic glutamate receptors, resulted in a much stronger and dose-dependent response in PPI hydrolysis and exposure in utero to ethanol significantly reduced this response. Tetrodotoxin, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), or (+/-)-3-(2-carboxypiperazine-4-yl)-propyl-1-phosphonic acid (CPP) had no effect on QA-stimulated PPI hydrolysis nor on the suppression of this hydrolysis by ethanol. Exposure in utero to ethanol did not affect PPI hydrolysis stimulated by a selective metabotropic glutamate receptor agonist, trans-(+/-)-l-amino-1,3-cyclopentanedicarboxylic acid (t-ACPD). Although the PPI hydrolysis stimulated by t-ACPD could be blocked by (RS)-alpha-methyl-4-carboxyphenylglycine (MCPG), an antagonist of the metabotropic glutamate receptor, MCPG was incapable of affecting QA-induced PPI hydrolysis and the suppressive effects of prenatal ethanol exposure on this hydrolysis. Taken together, the data suggest that the long-lasting suppressive effects of prenatal ethanol exposure on QA-stimulated PPI hydrolysis in cerebellar granule cell cultures is through a metabotropic QA receptor pathway that may be different from the one activated by t-ACPD.
Craniofacial morphology provides valuable data for determining races and ethnic groups and evolutionary adaptedness of prehistoric human population.Craniofacial investiation yield reliable clues to the ethnic of skeletal series,because craniofacial traits can be evaluated in different ethnic groups.The neolithic human skull of Chinese in this study are about 6000 years ago (B.C.4750-3700).Authors studied the neolithic human skull of Chinese with cephalometric radiography.
10 cases with maxillary development limited post surgical repairing of cleft palate and lip were undergone modified Le Fort I segmental osteotomy,that is,put the maxilla forward without velopharyngeal function change and oro-nasal fistula.By Computer Aided Simulation System for orthognathic surgery(CASSOS),analysis of dental pulp,evaluation of velopharyngeal function,compacting profile pre-to-post operation, authors described that surgical procedure has the satisfactory effectiveness.
We have previously reported a method for inducing natural suppressor (NS) cells by long-term culture of normal adult mouse spleen cells. The NS cells were further identified as mucosal or immature mast cells by morphology, cytochemistry, histochemistry and function. A cloned immature mast cell line was also confirmed to have NS activity. As NS cells, the cell line suppressed non-specifically the plaque-forming cell (PFC) response. The NS cell-free supernatant was partially enriched by chromatography and some fractions suppressed the PFC response and thymocyte proliferation. Heat treatment of the fractions failed to deplete the suppressive activity. The fractions were confirmed, by immunoblotting analysis, to contain transforming growth factor (TGF)-beta. Recombinant human TGF-beta was also able to suppress the PFC response and thymocyte proliferation. Neutralizing anti-TGF-beta reversed the suppression by both human TGF-beta and the fraction. From the above results, it is clear that mast cells displayed NS activity, at least partially, through the release of TGF-beta.
We measured serum T3, T4, FT3, FT4 and thyrotropin (TSH) by radioimmunoassay in 150 patients with epilepsy. Of the 150 epileptic patients, 120 cases received single antiepileptic drug, including Sod valproate (VPA), carbamazepine (CBZ), phenytoin (PHT), or MixtBrodsky (MB). Each subgroup consisted of 30 cases. The other 30 were untreated epileptics. The results suggested that there was no significant difference in serum thyroid hormone levels among healthy control group, untreated group, and hepatic non-enzyme-inducing anticonvulsant group (P < 0.05). As compared with the three groups mentioned above, the serum T3, T4, FT3, FT4 concentrations of the enzyme inducer groups were decreased, however, significant decrease was found in PHT group and CBZ group (P < 0.05, P < 0.005). All 12 patients with circulating thyroid hormone concentrations below normal reference values were given enzyme inducer. None of them revealed any clinical manifestation of hypothyroidism. There was no significant difference in serum TSH level among the above 6 groups (P < 0.05), and the serum TSH level of all patients was within normal reference limits. Our study showed that the changes of thyroid hormone in epileptics were due to the effect of some AEDs and not the disease itself. The disparity between the effect of enzyme inducer and that of non-enzyme-inducing anticonvulsants indicated that the hepatic microsomal enzyme system metabolizing thyroid hormone to be induced was the main mechanism for decreased serum thyroid hormone concentrations. Though the serum thyroid hormone levels of the enzyme inducer groups were decreased, no significant increase of the mean serum TSH concentration was found. This implies that AEDs may interfere the HPA function in some way.