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Biomedical subjects

L Zeng

Publications and source records attributed to L Zeng.

231 records · Page 13Linked to original sources
PubMed1991

[Galactose-1-phosphate uridyl transferase and congenital cataract].

The activity of red blood cells galactose-1-p-uridyl transferase (GPUT) was determined by the spectrophotofluorometric method. The average GPUT activity in 102 control subjects was 13. 34 +/- 2. 03u. There were no differences in the sexes and ages. The average GPUT activity in 108 patients with congenital cataract was 11.58 +/- 4. 03u and was lower than that of the controls (P < 0.01). The GPUT activity in 14 of the 108(12.96%)patients was all-3SD below the mean value of the controls (< 7.24u) and the range was from 4.02u to 7.13u with the mean value of 5. 93u being about 44.45% of the normal. The difference between the two groups was statistically significant (P < 0.001). The results indicated that some of the patients with congenital cataract were due to decrease in the GPUT activity. The patients with decrease GPUT activity were mainly suffering from cataracts and their systemic disease were mild.

Adolescent↗
PubMed1991

[A clinical study and analysis of congenital lenticular dislocation (35 cases)].

Thirty-five cases of congenital lenticular dislocation seen in our Center since 1985 have been studied and analyzed clinically. By the survey of pedigrees and examination of these patients, including ocular, systemic, skeletal X-ray, psychocardiogram, and urinary sodium-nitroprusside test, 21 cases were diagnosed as Marfan's syndrome, 6 cases as simple ectopia lentis, 3 cases as Weill-Marchesani's syndrome, 4 cases as aniridia and 1 case as homecys tinuria. We found that the most significant ocular manifestation of congenital lenticular dislocation was reduction in visual acuity. The severity of visual disturbance varied with the types of dislocation and the visual deficiency was closely related to the intermediate-grade (II) dislocation of the lens. Examination of ERG showed normal function in most of the patients. From this, we believe that the major cause of visual reduction in congenital lenticular dislocation is lenticular myopia and astigmatism. There fore, early diagnosis and effective correction of vision should be emphasized to prevent the occurrence of amblyopia.

Amblyopia↗
PubMed1991

[Waardenburg syndrome].

We report a patient with Waardenburg syndrome. He suffers from congenital deafness and presents high broad nasal root, synophrys, iris heterochromia and fundus hypopigment. The dystopia canthus is absence. In his family pedigree analysis, we found that his second cousin has oculocutaneous albinism.

Adolescent↗
PubMed1991

[Separation and quantitative determination of three saponins in licorice root by high performance liquid chromatography].

A new analytical method for the separation and simultaneous determination of three saponins in Licorice root by high performance liquid chromatography has been developed. The saponins, glycyrrhizic acid (S-I), uralsaponin B (S-II) and uralsaponin A (S-III) were separated and determined by use of the solvent system CH3CN-3% HOAc (H2O) (47:53) at 248 nm, and with gradient increasing flow rate, the operation can be completed in 20 min. This method is sensitive and acuate with good reproducibility. The contents of three saponins in Chinese Licorice roots derived from four Glycyrrhiza species were determined.

Anti-Infective Agents↗
PubMed1990

[New triterpenoidal sapogenins from the roots of Glycyrrhiza yunnanensis].

Two new pentacyclic triterpenoidal sapogenins of oleanane type, namely glyyunnansapogenin A (I) and glyyunnansapogenin B (II), together with a known compound beta-sitosterol were isolated and characterized from the roots of Glycyrrhiza yunnanensis Cheng f. et L. K. Tai, family Leguminosae, collected in Yunnan Province, China. I was obtained as its methyl ester (Ia), mp 276-277 degrees C, which formed a diacetate (Ic), mp 244-245 degrees C. II, mp 287-289 degrees C, gave a triacetate (IIb), mp 286-287 degrees C and a monomethyl ester (IIa), mp 272-275 degrees C, which further formed a triacetate (IIc), mp 187-189 degrees C and a diacetate (IId), mp 243-245 degrees C after treatment with acetic anhydride and pyridine over night at room temperature. The structures of I and II were established by spectral analyses of IR, 1H NMR, 13CNMR, MS, CD and ORD. Glyyunnansapogenin A (I) was proved to be 3 beta, 24-dihydroxy-16-oxo-olean-12-en-29-oic acid and glyyunnansapogenin B (II) 3 beta, 21 alpha, 24-trihydroxy-olean-12-en-30-oic acid respectively.

Chemical Phenomena↗
PubMed1990

[Glyyunnanprosapogenin and glyyunnansapogenin from the roots of Glycyrrhiza yunnanensis].

Two new triterpenoidal sapogenins of oleanane type, namely glyyunnanprosapogenin D (V) and glyyunnansapogenin F (IX) were isolated from the roots of Glycyrrhiza yunnanensis Cheng f. et L. K. Tai, family Leguminosae, collected from Yunnan Province, China. V was obtained as hexaacetate and dimethyl ester form (Vc), mp 168-170 degrees C, C56H78O22, which gave an aglycone macedonic acid (V') and two molecules of glucuronic acid after hydrolysis with hydrochloric acid. The spectral analysis of 13CNMR and 1HNMR showed that Vc had two glycoside residues attached to the aglycone, and therefore the structure of V was established as oleana-11, 13(18)-dien-29-oic acid, 3 beta, 21 alpha-di-(O-beta-D-glucuronic acid) pyranoside. IX was obtained as its diacetate and monomethyl ester form (IXc), mp 188-190 degrees C, C35H50O7. The IR, 1HNMR and UV spectra showed that the IXc had a skeleton of oleanane type triterpenoid with heteroannular diene. IXb, diacetate of IX, unpurified, was converted to IXf with chromium trioxide in glacial acetic acid. IXf, mp 160-164 degrees C, C30H46O8, was proved to be olean-12-en-11-oxo-3 beta,24-diacetoxy-18 beta-hydroxy-30-oic acid, 30 in equilibrium 18 beta lactone with another carbonyl group at C-15,16,21 or 22 by the analysis of 13CNMR, 1HNMR and MS spectra.(ABSTRACT TRUNCATED AT 250 WORDS)

Drugs, Chinese Herbal↗
PubMed1990

[Primary study of iontophoresis of zinc ion in treatment of retinitis pigmentosa].

We report here the preliminary effects of zinc iontophoresis in treatment of 26 Rp patients who had decreased zinc serum level or abnormal ratio of serum copper to zinc. Through more than 20 to 30 times of therapy, the vision of 15.38% eyes increased more than "3 lines", 4% eyes increased more than 5 degrees in the visual field, 13.46% eyes improved in dark adaptation threshold (greater than 1.0), the visual functions of the rest eyes were slightly improved or unimproved. The fundus didn't change before & after treatment. There were no changes of ERG in 8 eyes of 4 cases. In addition, the advantages and disadvantages between Zn iontophoresis and Zn compound taken orally, the improvement of vision by direct electric current therapy, the relationship between the metabolism of Zn element and Vit A and influence of Zn over the mechanism of dark adaptation were also briefly discussed.

Adaptation, Ocular↗
PubMed1990

[Effect of bronchoalveolar lavage fluid on silica-induced alveolitis in rats].

An experimental silicosis model was produced in rats by intratracheal instillation of 25 mg silica dioxide normal saline. Animals were killed at 1, 3, 7, 14, 45 days after treatment, for cytological, enzyme cytochemical and biochemical analyses of the bronchoalveolar lavage fluid. The results showed that the number of polymorphonuclear cells and alveolar macrophages (AMs) increased continuously. The total amount of protein and activities of LDH and AcP in the lavage fluid were elevated, while the activities of LDH, SDH and AcP demonstrated by enzyme cytochemical staining in AMs were lowered. The survival rate of AMs decreased and foamy AMs appeared, these changes reflected the main characteristics of silica-induced alveolitis. We conclude that silica-induced alveolitis is not only the essential pathological characteristics of early pulmonary reaction to silica, but also plays a crucial role in the pathogenesis of silicotic fibrosis.

Animals↗
PubMed1989

[Pathological study of bronchio-alveolitis induced by xinkang short-fiber chrysotile asbestos in rats].

Eighty-four rats were exposed intratracheally to 25 mg of locally produced Xinkang short-fiber chrysotile asbestos (98% of the fibers are less than 5 microns in length). In 1 to 3 d after instillation, the pathological changes in rat lungs demonstrated that the affection was mainly acute bronchio-alveolitis characterized by acute inflammatory exudation and injuries of the small airways and alveolar structural units. The four main manifestations of alveolitis induced by the chrysotile asbestos were of the neutrophilic, serous, alveolar macrophages and granulomatous varieties. Three types of pulmonary fibrosis developed gradually from 7 to 90 d following the exposure to the asbestos, i.e. the intraluminal, murally incorporated, and interstitial fibrosis. Findings showed the complete process from the acute inflammatory exudation and the damage to lung tissue, with the following repair and proliferation of injuried lung tissue and organization of exudate, to the final fibrosis and destruction of the lung. The results suggested that the persistent and irreversible damage to the epithelial cells of respiratory bronchioles and pneumocytes, and denudation and destruction of the basement membrane played an important role in the development of pulmonary fibrosis by forming a channel for the inflammatory exudates and fibroblasts migrating into the bronchioalveolar spaces. Therefore, the experimental results have proved that Xinkang chrysotile asbestos fibers less than 5 microns in length certainly have a fibrogenic effect.

Animals↗
PubMed1989

[Pathogenic effects of titanium dioxide dust on the lung of dogs--a histopathological and ultrastructural study].

Titanium dioxide (TiO2) dust has generally been regarded as a "nuisance dust" in experimental animals and men. In this experiment, 16 dogs were exposed intratracheally to TiO2 dust for 9-15 months. The scanning electron microscopy with energy dispersive analysis of X-ray (SEM-EDAX), performed to identify the elemental composition of dust particles used in the study and in the focal lesions of the lungs, showed that dust particles were nearly pure titanium. Dust in the lung deposited mainly in the respiratory bronchioles and adjacent alveoli, with many alveoli filled by compacted dust particles. The pulmonary responses consisted of slight alveolitis, centrilobular emphysema, focal collapse of alveoli, and fibroblast hyperplasia with a few collagen fibres surrounding some of the TiO2-dust foci. Electron microscopically, many alveolar macrophages with intact nuclei contained a great amount of dust particles in their lysosomes, and in the dust foci, most of type I pneumocytes disappeared and type I pneumocytes showed hyperplasia. The alveolar subepithelial basement membrane were markedly thickened and bundles of collagen fibres were formed in the interstice. These findings suggest that TiO2 dust is one of the sorts which probably induce mild lung fibrosis in case a large amount is deposited in the lung tissue.

Animals↗
PubMedDate not supplied

Failure of ketoprofen and interferon combination therapy to improve interferon-resistant chronic hepatitis C.

Preliminary reports suggest that patients with interferon (IFN)-resistant chronic hepatitis C respond better to a combination of IFN-alpha and nonsteroidal anti-inflammatory drugs than to IFN alone. The efficacy of IFN combined with ketoprofen in the treatment of patients with IFN-resistant chronic hepatitis C was evaluated. Seventeen patients, nonresponsive after at least six months of treatment with IFN-alpha 2b and subsequently treated with the combination of IFN-alpha 2b plus ketoprofen for four months, were studied. Serum aminotransferases (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]) and serum hepatitis C virus (HCV) RNA were analyzed before and throughout treatment. No patient normalized serum aminotransferases after combination therapy. There were no significant differences in mean serum ALT and AST levels before and after ketoprofen intervention. Serum HCV RNA became undetectable after treatment in only one patient, but was detectable again three months after treatment cessation. These results provide no convincing evidence that the combination of IFN-alpha 2b with ketoprofen improves the response to IFN in patients nonresponsive to IFN alone.

Adult↗