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Biomedical subjects

J C Liu

Publications and source records attributed to J C Liu.

At least 145 records · Page 8Linked to original sources
PubMed1989

Intravitreal injection of piperacillin.

Piperacillin was injected into the vitreous body of rabbit eyes to evaluate its suitability for intraocular injection and its toxicity on intraocular tissues. Doses ranged from 50 micrograms to 3,000 micrograms. Toxicity was determined through histology and electroretinograms by comparing the piperacillin-injected eyes with eyes injected with balanced saline solution. Retinal toxicity was noted in the outer layer of the retina when 3,000 micrograms was injected intravitreally. No toxicity was noted by histology with 1,500 micrograms of piperacillin. The minimal inhibitory concentration of piperacillin is 800 micrograms/cc for both gram negative and gram positive organisms. The large dose of intravitreal piperacillin tolerated by rabbit eyes makes piperacillin a potentially safe and effective broad spectrum antibiotic for the treatment of bacterial endophthalmitis in human eyes.

Animals↗
PubMed1988

Sympathetic postganglionic innervation of the cardiac coronary artery in cats.

The localization of the sympathetic postganglionic neurons innervating the cardiac coronary arteries of the cat was investigated using retrograde axonal transport with horseradish peroxidase. We found after the enzyme was applied to the main trunk of the right coronary artery, and to the main trunk and the terminal branch of the ventral descending vessels of the left coronary artery, the peroxidase-labeled sympathetic neurons were localized predominantly in the right stellate ganglia, with a few cells in the left stellate ganglia. There were very few labeled cells in the middle cervical, superior cervical, and T4-7 ganglia on both sides. After peroxidase application to the terminal branch of the dorsal descending vessels of the right coronary artery, labeled cells were mainly in the left stellate ganglia, with only a few cells in the right stellate ganglia.

Animals↗
PubMed1988

Assessment of the relative locations of the greater palatine foramen in adult Chinese skulls.

One hundred dry skulls of adult Chinese of both sexes were studied. They were homogeneous in the form of maxillary arch and having full eruption of the upper third molar, without missing teeth and malposition of teeth. Our findings revealed that the mean distance from the center of the greater palatine foramen (GPF) to the midsagittal plane of the hard palate was 16.00 mm, and to the posterior border of the hard palate, 4.11 mm. The location of the GPF related to the maxillary molars was expressed as percentage in 5 relations. We found that the most common location of the GPF was between the maxillary second and third molars (relation III: 48%), and less common was lingual to the maxillary third molar (relation IV: 33.5%). The usually accepted description of the GPF location was lingual to the second molar (relation II), but in our study this relative position occurred in only 17% of the skulls. The long axis of the greater palatine canal directing to the GPF in the oral cavity was found to be directed anteriorly in 181 openings (90.5%) of the 200 GPF, and only 19 openings (9.5%) directed vertically. The bilateral symmetry of GPF on both sides of each skull was remarkable. The discrepancy of our observations on the Chinese skulls from those on other ethnic groups was discussed. Our findings suggest, therefore, the existence of an ethnic variation and the necessity of a more accurate method of locating the GPF in clinical practice.

Anatomy, Regional↗
PubMed1988

New stereotactic technique for percutaneous thermocoagulation upper thoracic ganglionectomy in cases of palmar hyperhidrosis.

To perform unilateral or bilateral upper thoracic ganglionectomy, we established a three-dimensional system of coordinates for T2 and T3 ganglia. For this purpose, the spatial relations were represented by drawings obtained from 50 Chinese cadavers. A simple stereotactic frame was constructed as an aid in performing the procedure. Then, according to the established three-dimensional system of coordinates, percutaneous thermocoagulation of both T2 and T3 ganglia was performed on 10 patients (20 sides) with palmar hyperhidrosis, under local anesthesia and fluoroscopic guidance at the posteroanterior projection. Excellent relief of abnormal sweating in 19 of the 20 hands was achieved. Partial relief was obtained in the remaining hand. No complication was observed in our patients. The technique has been proved to be safe, effective, and simpler than other methods now in use.

Animals↗
PubMed1987

Serotyping and subgrouping of some rotavirus strains in China.

This article reports for the first time in China the results of serotyping and subgrouping of some rotavirus strains obtained from faecal fluids of cases with infant diarrhoea. Infant diarrhoea rotavirus serotype 1 (Wa strain)-specific and serotype 2 (KUN strain)-specific hyperimmune sera, and infant diarrhoea rotavirus serotype 3-specific, rotavirus subgroup I-specific and subgroup II-specific monoclonal antibodies were used in serotyping and subgrouping by means of enzyme-linked immunosorbent assay of 14 rotavirus strains which had been identified by electron microscopy. Results showed that three out of four Beijing strains in 1982 belonged to serotype 2 and subgroup I rotavirus, one belonged to serotype 3 and subgroup II rotavirus; one out of nine Beijing strains in 1984 belonged to serotype 1 and subgroup II rotavirus, seven belonged to serotype 2 and subgroup I rotavirus, one belonged to serotype 3 and subgroup II rotavirus; and one Kunming strain in 1984 belonged to serotype 3 and subgroup II rotavirus.

Antibodies, Monoclonal↗
PubMed1986

Antibody against adult diarrhoea rotavirus among healthy adult population in China.

This paper deals with a method of using unknown serum as the first antibody to coat wells of the microtiter plate directly in application of the sandwich ELISA method with double antibodies for the assay of the antibody against adult diarrhoea rotavirus. This method was used for assay of the antibody against adult rotavirus in 1,380 sera of healthy adults obtained from some provinces and cities of China, of which 141 showed a positive result with a total positive rate of 10.2%. The infection rate varied in different regions. In order to confirm the accuracy of these results a blocking test was carried out on 25 positive specimens, and the results revealed that the P/N ratios after blocking were all lower than those before blocking. Seventeen of these 25 positive serum specimens were obtained from rural areas of Qian'an County, Hebei Province where epidemic adult diarrhoea had occurred two years ago. The antibody against adult diarrhoea rotavirus was not detected in 50 adult sera from Xizang Autonomous Region. Only one out of 50 adult sera from Hainan Island was positive for the antibody.

Adult↗
PubMed1986

A clinical and anatomical study of the location of the mental foramen in adult Chinese mandibles.

One hundred mandibles of adult Chinese cadavers of both sexes without missing teeth, alveolar bone resorption and malposition of teeth were studied. The anatomical location of each mandibular mental foramen was measured by using a combination of three previous methods. Our results showed that the location of the mental foramen below the apex of the lower second premolar (relation IV: 58.98%) was the most common. On average, the distance between the most anterior portion of the anterior border of the mental foramen and the mandibular symphysis was 28.06 mm, between the most anterior portion of the anterior border of the mental foramen and the posterior border of the ramus 74.14 mm, between the inferior border of the mental foramen and the lower border of the mandibular body 14.70 mm, between the superior border of the mental foramen and the bottom of the lower second premolar socket 2.50 mm. The distance across the mental foramen between the alveolar crest and the lower border of the mandibular body was 30.29 mm. Our results were compared with those of other investigators. The significance of identifying the anatomical location of the mental foramen in dental practice is discussed.

China↗
PubMed1986

Mutagenesis in vitro by DNA polymerases alpha, beta and gamma.

In an attempt to understand the molecular mechanisms of spontaneous and induced mutagenesis in higher organisms, the mutational specificities of highly purified DNA polymerases alpha, beta and gamma have been assessed for a single round on in vitro DNA synthesis with undamaged, biologically active DNA. A forward mutational assay in a nonessential gene has been used, which is capable of detecting frameshift and deletion errors in addition to all twelve possible base substitution errors at 96 different positions in a 250 base target sequence (the lacZ alpha gene in M13mp2 DNA). DNA sequence analyses of over 1000 mutants generated by these enzymes demonstrate the production in vitro of all three classes of errors. The frequencies and specificities of these mutations are highly distinctive for each class of DNA polymerase. These data point to properties of both the DNA and the enzymes themselves which are important in determining the frequency and specificity of spontaneous and perhaps induced mutagenesis.

Animals↗
PubMed1986

[The prevalence of Paragonimus westermani in Taipei County].

Paragonimus westermani is an endemic disease and has had scattered distribution in Northern Taiwan for the long period of 108 years. In order to know the current status of the prevalence of this disease in Taipei County, an investigation by means of examination of snail, crab and stool for identification of cercariae, metacercariae and ova of Paragonimus westermani was carried out in five small highly endemic foci-Alilao, Shengkeng, Shuangchi, Shihjen and Taiping from July 1984 to June 1985. The results obtained are summarized as follows: The infection rate for 17, 412 fresh-water snails, Semisulcospira libertina, the first intermediate host and for 180 fresh-water crabs, Eriocheir japoniucs, the second intermediate host was both negative in the first four places. On the contrary, the rate for 879 fresh-water snails, Semisulcospira libertina, for 298 fresh-water crabs, Potamon miyazaki and Potamon dehaani and for 45 school-children was zero, 26.8% and zero respectively, in the last one. Based on the above findings, it is concluded that in the last 20 years, Paragonimus westermani might probably be under control in the former areas which are now developed districts. This development has probably influenced the prevalence and distribution of the disease. But it is still prevalent in the latter area located in remote undeveloped mountain.

Animals↗
PubMed1985

Horseradish peroxidase localization of the sympathetic postganglionic neurons innervating the cat heart.

The localization of the sympathetic postganglionic neurons innervating the cat heart has been investigated by using retrograde axonal transport of horseradish peroxidase (HRP). HRP was injected into the subepicardial layers of 4 different cardiac regions. The animals were sacrificed 72-96 h later and fixed by perfusion via the left ventricle. The paravertebral sympathetic ganglia from the superior cervical, middle cervical and stellate ganglia to T10 ganglia were removed and processed for HRP identification. Following injections of HRP into the apex of the heart, the sinoatrial (SA) nodal region and the ventral wall of the right ventricle, we observed that HRP-labeled sympathetic neurons were localized predominantly in the right stellate ganglia, and to a lesser extent, in the right superior and middle cervical ganglia, and left stellate ganglia. Fewer labeled cells were found in the right T4-T6. T8 and T9. After HRP injection into the dorsal wall of the left ventricle, HRP-labeled cells were present mainly in the left stellate ganglia.

Animals↗
PubMed1985

Retrograde localization of the innervation of the middle cerebral artery with horseradish peroxidase in cats.

The innervation of the middle cerebral artery (MCA) of the cat was studied by applying horseradish peroxidase (HRP) to the wall of the right MCA. After a survival period of 48 to 72 hours, the bilateral superior cervical ganglia, middle cervical ganglia, stellate ganglia, T-4 sympathetic paravertebral ganglia, geniculate ganglia, semilunar ganglia, nodose ganglia, and brain stem including midbrain, pons, and medulla oblongata were removed to be processed with tetramethyl benzidine. HRP-labeled neurons were found in the ipsilateral superior cervical ganglion, semilunar ganglion, and dorsal raphe nucleus. The other areas did not have HRP activity. The results suggest that the adrenergic nerves innervating the MCA originate in the ipsilateral superior cervical ganglion, the sensory nerves originate in the ipsilateral semilunar ganglion, and the serotonergic nerves originate in the ipsilateral dorsal raphe nucleus. Cerebral arterial constriction may relate to the intrinsic (intracerebral) neurogenic pathway involving the trigeminal nerve and the dorsal raphe nucleus.

Animals↗