Biomedical subjects
Publications and source records attributed to S Jiang.
The fluorescence behavior of the system and the conditions of the title method has been studied. Non-ionic surfactant op was added to increase the sensitive and stability of the determination. This method has been applied to the determinations of phosphorous in some black foods. Both the accuracy and precision are satisfactory.
The conditions of title method has been studied. In this paper coefficient correction was used to eliminate the interference of benzo(k)fluoranthene. The method has an advantage of covenient and rapid. The results of real samples are satisfactory.
A set of resonance Raman spectrometer with excitation lines continuously tunable in 220-970nm, which is a first set in China, has been assembled. The factors influenced on the signal noise ratio (SNR) of spectra were analyzed in detail. The methods to improve the SNR were suggested and the parameters of the spectrometer were optimized. A satisfied Raman spectra can be obtained.
Bovine beta-lactoglobulin chemically modified with 3-hydroxyphthalic anhydride (3HP) was recently shown, at nanomolar concentrations, to block the binding site on CD4 for the HIV surface glycoprotein (gp120), potentially inhibiting HIV transmission. Human glycodelin has sequence homology with bovine beta-lactoglobulin and appears as different glycoforms in endometrium (GdA) and seminal plasma (GdS). We studied the anti-HIV effects of chemically modified GdA and GdS on both the infection of MT-2 cells by HIV-1IIIB, and the infection of peripheral blood mononuclear cells by the primary HIV isolate THA/93/051 belonging to subtype E. Whereas the native proteins were inactive when tested at physiologic concentrations, nanomolar concentrations of either 3HP-GdA or 3HP-GdS inhibited the production of HIV nucleocapsid p24, cytopathic effects of HIV-1IIIB, and infection of peripheral blood mononuclear cells by the primary HIV isolate THA/93/051. Moreover, both modified proteins inhibited gp120-CD4 binding, 3HP-GdS being more potent than 3HP-GdA (p = 0.0042). Because GdA and GdS have the same major protein core, the observed difference in gp120-CD4 binding must depend on the specific glycoform. In view of the previously reported contraceptive activity of GdA, the observed anti-HIV activity induced by its chemical modification should be of special interest in the development of antiviral strategies that may also have contraceptive effects.
OBJECTIVE: To study the difference of endocrine characteristics between patients with luteal phase deficiency (LPD) and inadequate endometrial response (IER). METHODS: Serum estradiol (E2), progesterone (P), follicle-stimulating hormone, luteinizing hormone and prolactin levels were determined by radioimmunoassay in cycles of LPD, IER and normal controls. Contents of endometrial cytoplasmic estradiol receptors (ERc), nuclear estradiol receptors (ERn), cytoplasmic progesterone receptors (PRc) and nuclear progesterone receptors (PRn) were determined by dextran coated charcoal assay in the same cycle. RESULTS: Serum E2 and P levels in the luteal phase of patients with LPD were significantly lower than those of normal group (P < 0.001), no significant difference of endometrial estrogen receptor and progesterone receptor contents was found between the two groups (P > 0.1). Serum E2 levels in both follicular and luteal phase of IER patients were significantly lower than those of normal groups (P < 0.001), but serum P levels in luteal phase of the two groups showed no difference (P > 0.1). The contents of ERc and PRn in proliferative phase and PRc contents throughout the menstrual cycle were also lower than those of the normal group (P < 0.001, < 0.001 and < 0.05 respectively). CONCLUSIONS: These results indicate that LPD and IER are two distinct entities in terms of endocrine characteristics. To distinguish underdeveloped endometrium caused by either LPD or IER is the key to choose appropriate treatment.
The volume of cochlear nucleus and nucleolus, neural populations were determined in rats of three groups aged (1, 2-3, 22-28 months). The study data indicated that there is no difference between the volume of cochlear nucleus in the aged and adult animals (P > 0.05). Compared with the other two groups, the aged animals show a reduction of volume of necleolus of cochlear nucleus neurons (P < 0.01), a loss of neurons (spherical cell and multipolar cell) (P < 0.01). On the other hand, it shows an increase in number for the glial cells in the aged animals (48.48%, P < 0.01). Quantitative results of the cell of cochlear nucleus were analysed. We suggest that central changes also play an important role in presbycusis.
OBJECTIVE: To investigate the effect of acoustic overstimulation on concentrations of cations in cochlear endolymph and analyze the relationship between the ionic changes in endolymph and the hearing loss. METHODS: The endocochlear potentials (EP), K+, Na+ and Ca2+ concentration in cochlear endolymph were examined in vivo for normal and 167 +/- 2 dB SPL impulse noise exposed groups of guinea pig bored on time course by means of double-barreled ion-selective microelectrodes. Brain stem auditory evoked potential (BAEP) was used to evaluate the auditory function. Ca(2+)-ATPase activity was demonstrated cytochemically in the lateral cochlear wall as induced by Ando et al with slight modification. RESULTS: The K+ and Ca2+ concentration exhibited significant changes in 8-hour groups (P < 0.05 for K+ and P < 0.01 for Ca2+). Then the K+ concentration was eventually resumed to the initial levels in accordance with the EP recovery in 7 days, while during the same period Ca2+ concentration was always significantly higher than that in control group (P < 0.01). The BAEP threshold shifts were correlated well with changes in ionic concentrations, especially Ca2+ (P < 0.001), in the endolymph induced by acoustic trauma. Although the normal positive EP was observed 7 days after noise exposure, the function of the vascular stria was not completely restored as revealed by the fact that the Ca(2+)-ATPase was diffused to the apical membrane surface. CONCLUSIONS: Endolymph compartment intrinsic mechanism for maintaining ionic composition is seriously deteriorated after high impulse noise stimulation. The changes of the unique environment of endolymph may play an important role in the mechanism of sensorineural hearing loss induced by acoustic trauma.
OBJECTIVE: To establish the 3-D(three-dimensional) morphological study of the temporal bone by means of computer graphic techniques. METHODS: The serial sections of the temporal bone were processed by the technique of computer-aided 3-D reconstruction. The 3-D images of the multi-structures in the temporal bone were displayed on the monitor. The 3-D parameters of these structures were measured by a special software. The stereo-images of the structures in the temporal bone were obtained by stereoscopy and stereo-pairs. RESULTS: Most structures of the temporal bone were reconstructed in 37 instances for the different purpose of study. Each set of the stereo-pair corresponding to the structures in the temporal bones and many 3-D parameters were obtained. The complex spatial relationship among the reconstructed structures such as the facial nerve, endolymphatic sac, posterior tympanum and posterior ampullary nerve was revealed and the mechanic model of the ossicular chain was set up. According to these results, the surgical approach of the posterior ampullary nerve transection was designed and simulated on the graphic computer. CONCLUSION: The technique of computer-aided 3-D reconstruction provides a new tool for the study of the temporal bone. It is also helpful for the designs and simulations of the surgical approaches. The results of this study contribute to developmout of a new branch of pathology of the temporal bone and a primary 3-D morphological study of the temporal bone.
OBJECTIVES: To treat 212 cases of typhoid fever with Seven kinds of fluoroquinolones (FQNS) and to evaluate their clinical efficacy, bacterial susceptibility and adverse drug reaction (ADR). METHODS: All the cases were hospitalized and uniantibiotic treated in which NFX group (n = 43) was compared with CP group (n = 28). RESULTS: 204/212 (96.23%) cases were positively cultured. All except 9 (S. paratyphi) were S. typhi. Of the 212 clinically isolated strains, 194(91.51%) were susceptible to FQNS with K-B assay. The MIC except 1 (6.25 mg/L) were all < or = 4 mg/L. The results of MIC detection with 20 strains of clinically isolated bacteria in 1994 and 1995 showed that FQNS were apparently superior to other antityphoid fever antibiotics as chloramphenicol and cefoperazone. When FQNS were used the overall clinical cure rate was 98.11%, the bacterial clear rate was 99.51%, and the rate of ADR was 11.3%. No difference was found between the NFX group and CP group in defervescent days and the cure rates and bacterial carrier state in recovery. The rate of recurrence and ADR in the NFX group was lower than that in the CP group. With the improvement of pharmacokinetics, new FQNS can be administered once or twice a day, and the therapy course shortened from 14 to 7 days. It is considered that FQNS are currently the first choice of antibacterials in treating typhoid fever.
By using PCR-SSCP method, 21 specimens of nasal cavity and paranasal sinuses carcinomas which were freshly frozen and paraffin embedded were detected for the mutation of p53 gene (exon 6). The overall mutation frequency of patients was 67% (14 out of 21), which was 33% (1 out of 3), 50% (3 out of 6), 67% (4 out of 6) and 100% (6 out of 6) respectively in clinical stage I to IV, 33% (2 out of 6), 67% (4 out of 6) and 89% (8 out of 9) respectively in well, moderately and poorly differentiated carcinomas, and 100% (4 out of 4) and 59% (10 out of 17) respectively in lymph-node metastasis and non-lymphnode metastasis. It was not statistically significant when the Chi-square test was applied (P > 0.05), but there was a tendency towards an increase in p53 mutation frequency with highly malignant, poorly differentiated and lymph-node metastasis carcinomas. The results indicate that the mutation of p53 gene plays an important role in the initial and progression of nasal cavity and praranasal sinuses carcinomas. Detection of p53 mutation using the above sensitive and rapid method reveals practical significance for judging malignant level and evaluating prognosis of nasal cavity and paranasal sinuses carcinomas.
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The mediorostral neostriatum/hyperstriatum ventrale (MNH) and neostriatum dorsocaudale (Ndc) of the domestic chick are crucially involved in auditory filial imprinting, whereas the lobus parolfactorius (LPO) seems to be involved in the emotional modulation of behavior. Because there is evidence that MNH and Ndc are akin to higher association areas in mammals, the present study evaluates the dopaminergic and thalamic input to these areas, as well as to the avian caudate/putamen homologue LPO, by using retrograde pathway tracing, together with dopamine (DA) and tyrosine hydroxylase (TH) immunohistochemistry. By combining DA immunohistochemistry with retrograde fluorescent tracing, we demonstrated that dopaminergic afferents to the MNH and Ndc arise mainly from the area ventralis, whereas the main dopaminergic input to the LPO arises from the substantia nigra. The main thalamic input to the MNH and LPO arises from the dorsal thalamic nuclei, n. dorsomedialis anterior and n. dorsolateralis anterior, whereas the thalamic input to the Ndc arises from the n. dorsolateralis posterior and n. subrotundus. Furthermore, there are reciprocal intratelencephalic connections between distinct parts of the neostriatum caudale and the mediorostral neostriatum. DA-immunoreactive (ir) fibers are present at moderate densities in the MNH and Ndc and at high densities in the LPO. At the ultrastructural level, DA- and TH-ir axon terminals in the MNH and Ndc form predominantly symmetric synaptic contacts with dendritic shafts, which are often situated in close vicinity to unstained terminals. These results indicate that the general organization of dopaminergic afferents to the chick telecephalon is similar to that of the mesotelencephalic dopaminergic subsystems in mammals such as the mesostriatal and mesolimbocortical DA system.
Heme oxygenase (HO-1) is the rate-limiting enzyme in heme catabolism. HO-1, a stress protein, has been suggested to be involved in defense mechanisms against agents that may induce oxidative stress. It has been proposed that renal HO gene expression regulates important hemoprotein(s) such as cytochrome P450 and may be essential to maintain homeostasis in the kidney. Because accurate assessment of HO-1 mRNA in normal and disease states in kidney were not available due to the limited number of cells, we developed a system to quantitate human HO-1 mRNA in samples limited in cell number and/or mRNA copies. Total RNA from human kidney was used to establish this technique; it was reverse-transcribed and then amplified by polymerase chain reaction (PCR) in a tube also containing an internal standard obtained by deleting 50 bp from the original human HO-1 gene. This allowed us to use the same primers for both the sample and internal standard. After amplification, templates were resolved by acrylamide gel electrophoresis and quantitated either by densitometry or radioactivity counted from the bands excised from the gel. When the internal standard is present in the reaction mixture, the ratio of amplified sample vs. the standard template is proportional to the amount of sample RNA, and it is therefore possible to calculate the number of specific mRNA molecules. We have used this approach to quantitate the number of HO-1 mRNA molecules in adenocarcinoma cells. Results show that reverse transcription (RT)/PCR methods were able to determine the number of HO-1 mRNA copies in biopsy samples of human adenocarcinoma cells.
A human hepatocellular carcinoma cell line, SMMC-7721, was treated with all-trans-retinoic acid (RA) and phorbol 12-myristate 13-acetate (PMA) to induce its differentiation and proliferation respectively. A biantennary sugar chain fluorescently labelled with 2-aminopyridine (PA), GlcNAc beta 1-2Man alpha 1-6(GlcNAc beta 1-2Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4GlcNAc-PA, was used to detect the activity of beta-1,4-galactosyltransferase on the cell surface by HPLC. The results show that the activity of beta-1,4-galactosyltransferase on the cell surface increases when the cell is treated with RA, but decreases when it is treated with PMA, whereas the activities of the whole cell remain stable during the treatments.
The International Index is a powerful predictor of outcome in the aggressive non-Hodgkin's lymphomas that is based solely on clinical features. Proliferative activity (% S-phase) measured by flow cytometry has been reported to have prognostic significance in many series and may represent a biologic correlate of clinical behavior that further defines prognosis. Flow cytometric analysis of cellular DNA content and proliferative activity (% S-phase) was performed on fixed paraffin-embedded biopsy specimens from 242 previously untreated patients with diffuse, aggressive non-Hodgkin's lymphomas entered on phase III intergroup clinical trials. The International Index was calculated for each patient based on stage, lactate dehydrogenase, performance status, number of extranodal sites, and age, as previously reported. The International Index consistently predicted response to therapy (P = .027) and survival (P = .007) in this series. DNA aneuploidy was shown in 57% of cases, but was not predictive of clinical outcome. The median % S-phase was 9.9 (median coefficient of variation, 3.6%), which was highly correlated with mitotic index (P = .0001). Although a trend associating low proliferative activity with good early survival and very high S-phase with a shortened survival was shown, International Index risk was the only significant predictor of survival in the multivariate analysis. Although proliferative activity quantitated by flow cytometric analysis of nuclei extracted from paraffin-embedded specimens is probably predictive of survival, it is a less powerful prognostic indicator than clinical parameters represented by the International Index and provides no additional prognostic information.
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The Rho family of GTPases control diverse biological processes, including cell morphology and mitogenesis. We have identified WASP, the protein that is defective in Wiskott-Aldrich syndrome (WAS), as a novel effector for CDC42Hs, but not for the other Rho family members, Rac and Rho. This interaction is dependent on the presence of the G protein-binding domain. Cellular expression of epitope-tagged WASP produces clusters of WASP that are highly enriched in polymerized actin. This clustering is not observed with a C-terminally deleted WASP and is inhibited by coexpression with dominant negative CDC42Hs-N17, but not with dominant negative forms of Rac or Rho. Thus, WASP provides a novel link between CDC42Hs and the actin cytoskeleton, which suggests a molecular mechanism for many of the cellular abnormalities in WAS. The WASP sequence contains two novel domains that are homologous to other proteins involved in action organization.
The visinin-like protein (VILIP) is a member of a recently discovered family of calcium sensors specifically expressed in neurons. Family members contain four potential calcium-binding domains commonly referred to as "EF-hand motifs". VILIP interacts in a calcium-dependent manner with the actin-based neuronal cytoskeleton and modulates the phosphorylation of G-protein-coupled receptors, i.e., rhodopsin, in vitro. Here, we have used antisera against VILIP to study its distribution in the chick brain. Immunostaining of subsets of neurons is observed throughout the brain. Generally, the distribution of VILIP coincides well with the distribution of VILIP transcripts as detected previously by in situ hybridization. The most intense expression is detected in the visual system and the cerebellum. In the visual system, neurons of the nuclei of the ascending tecto-fugal pathway are stained, as are the pretectal, isthmic, and oculomotor nuclei. VILIP immunoreactivity is found in cell bodies, dendrites, and synaptic structures. Thus, VILIP appears to be an excellent marker for the characterization of neurons of the visual pathway. In the cerebellum, VILIP immunoreactivity is detected in deep cerebellar nuclei and in a subset of granule cells, Golgi type II cells, basket cells, and stellate cells, whereas it is completely absent from Purkinje cells. Intense punctate staining in the molecular layer suggests that VILIP is transported from deep cerebellar nuclei and from granule cells to the glutamatergic climbing-fiber and parallel-fiber synapses, respectively, both of which terminate on Purkinje-cell dendrites. The localization of VILIP in these presynaptic terminals has been confirmed at the electron-microscopic level.