Biomedical subjects

Xiaofeng Lin

Publications and source records attributed to Xiaofeng Lin.

24 records · Page 2Linked to original sources

PubMed2003

Removal of intralenticular magnetic foreign bodies with intraocular magnet.

PURPOSE: To investigate the possibility of conservation of the lens after removal of intralenticular magnetic foreign bodies with intraocular magnet. METHODS: Intralenticular magnetic foreign bodies of 15 patients were removed by using an intraocular magnet. The lens of each injury eye was conserved. Follow-up observation of these cases ranged from one to four years. RESULTS: The intralenticular magnetic foreign bodies of 15 patients were successfully removed. The lens of each injury eye was conserved and the transparence of the lens was properly maintained. Sizes of these foreign bodies were measured, ranging from 0.3 mm to 3 mm in diameter. The follow-up observation showed that the corrected visual acuity of 14 cases was not changed after operation. CONCLUSIONS: The intraocular magnet is very helpful for removal of magnetic foreign bodies from the transparent lens. This magnet allows removing of the foreign body by the surgeon and no damage to the lens was induced during the operation. Thus, maintenance of visual acuity of most of the patients can be achieved.

Accidents, Occupational↗

PubMed2003

Experimental studies of melanin associated antigen and its relationship with sympathetic ophthalmia and Vogt-Kayanagi-Harada syndrome.

PURPOSE: To discuss the relationship of Bovine Melanin-Associated Antigen (BMAA) to Sympathetic Ophthalmia (SO) and Vogt-Kayanagi-Harada (VKH) syndrome. METHODS: BMAA was isolated and purified from bovine iris and ciliary body and MTT method was used to measure the peripheral lymphocyte reactions of SO and VKH syndrome patients to BMAA. 15 cases of SO were included in the SO group with 11 males and 4 females. The average age was 37.5, ranging from 23 to 56 years; 15 patients with VKH syndrome were included in the VHK group with 7 males and 8 females. Their average age was 37.2 years, ranging from 24 to 69 years; 20 normal individuals without ocular and systemic autoimmune diseases were included in the control group. These included 9 males and 11 females, aging from 14 to 28 with an average of 23.8 years. RESULTS: The OD values of each group were as follows: SO controls 0.327 +/- 0.032; SO + BMAA 0.490 +/- 0.758; SO + PHA 0.5310 +/- 0.918; VKH controls 0.328 +/- 0.503; VKH + BMAA 0.430 +/- 0.530; VKH + PHA 0.328 +/- 0.484; Normal controls 0.304 +/- 0.267; Normal + BMAA 0.343 +/- 0.326; Normal + PHA 0.477 +/- 0.598. The average OD values of peripheral lymphocytes to BMAA stimulation in SO patients and normal controls were 0.490 and 0.343 respectively. The difference was statistically significant, P < 0.001; The average OD values of peripheral lymphocytes to BMAA stimulation in SO and VKH syndrome patients were 0.470 and 0.430 respectively. The difference was not statistically significant, P > 0.05. CONCLUSIONS: BMAA effectively stimulate the proliferative reaction of peripheral lymphocytes in SO patients and BMAA may act as an antigen and contribute in the pathological process of SO. No difference in proliferative reaction of peripheral lymphocytes was found between SO and VKH syndrome patients after BMAA stimulations and BMAA may be involved in the development of both SO and VKH syndrome.

Adult↗

PubMed2002

Contribution of an active site cation-pi interaction to the spectroscopic properties and catalytic function of protein tyrosine kinase Csk.

Csk is a soluble protein tyrosine kinase that phosphorylates and negatively regulates protein tyrosine kinases of the Src family. The spectral properties of the intrinsic Trp fluorescence of Csk and their underlying structural features were investigated in combination with urea denaturation and site-specific mutagenesis. It was found that W352 contributed approximately 35% of the total Trp fluorescence of Csk even though seven other Trp residues were present. The enhanced contribution by W352 to Csk fluorescence was due to an interaction between its indole ring and the positively charged guanidino group of R318. W352 is located on the peptide substrate binding P+1 loop, and R318 is located on the catalytic loop. The W352-R318 interaction, called a cation-pi interaction, uniquely couples the two loops in the active site. Mutations that disrupted this coupling resulted in varying levels of decreases in Csk activity, and consistent and significant increases in K(m) values for its physiological substrate, Src protein tyrosine kinase. These results indicated that structural coupling between the two loops by the cation-pi interaction played an important role in Csk substrate binding. Since both R318 and W352 are highly conserved among protein tyrosine kinases, this cation-pi interaction is likely a signature structural feature of most, if not all, PTKs. These studies elucidated the roles of two conserved signature residues in Csk and formed a baseline for further structure-function studies of Csk and other PTKs.

Animals↗

PubMed2002

[Application of neuroendoscopy in brain surgery].

OBJECTIVE: To investigate the effect of neuroendoscope on surgery. METHODS: 315 patients were treated with neuroendoscope. Endoscopic neurosurgery (EN) was used in 219 patients, endoscope-assisted microneurosurgery (EAM) in 72, and endoscope-controlled microneurosurgery (ECM) in 24. RESULTS: 201 (91.8%) of the 219 patients underwent EN effectively. In 72 patients who underwent EAM there was less retraction during tumor removal and visual control was improved. 21 (87.5%) of the 24 patients underwent ECM effectively. No severe complications were observed. CONCLUSION: Neuroendoscopy can reduce tissue trauma, improve visualization during tumor removal, and reduce complications.

Brain Neoplasms↗

PubMedDate not supplied

Nosocomial infection in an eye hospital: incidence and occurrence patterns.

PURPOSE: To describe the incidence and occurrence patterns of nosocomial infections in a large eye hospital over a 6-year period. METHODS: Medical records of 94,013 consecutive inpatients admitted to Zhongshan Ophthalmic Centre, Guangzhou, China, from 1996 to 2002, were reviewed. Demographic data and infection diagnoses were collected. Nosocomial infection was defined as an infection that was absent during preadmission assessments but detected at least 48 h after admission to the hospital, or occurred after surgical procedures performed within the hospital. RESULTS: The cumulative incidence of nosocomial infections over a 6-year period was 0.28%. The most common infections were acute conjunctivitis (45.5%) and upper respiratory tract infection (36.4%), followed by suppurative endophthalmitis (8.3%). Patients with acute conjunctivitis were predominantly adults aged from 15 to 59 years (60%), while patients with upper respiratory tract infection were predominantly children of 14 years or younger (74.0%), and those with endophthalmitis predominantly older persons 60 years or older (68.2%). Conditional pathogenic bacteria, mainly gram-positive, were responsible for most suppurative endophthalmitis cases. CONCLUSIONS: Although nosocomial infection incidence is relatively low in this eye hospital, our data suggest that different subgroups of patients are prone to certain types of infection. Specific preventive strategies targeting different subgroups of inpatients may further reduce the infection incidence.

Adolescent↗

PubMedDate not supplied

Establishment of a new amphileptid genus, Apoamphileptus nov. gen. (Ciliophora, Litostomatea, Pleurostomatida), with description of a new marine species, Apoamphileptus robertsi nov. spec. from Qingdao, China.

A new pleurostomatid genus Apoamphileptus is described, which is diagnosed as: Belonging to the Amphileptidae with spica on right side; on each side of the cell, a single perioral kinety, which encircles the cytostome and does not extend to the posterior end of the cell; somatic kineties of both sides near ventral margin shortened and forming a postoral suture; two to several extra fragments with densely arranged dikinetids located in anterior portion of left side. As the type species, the morphology and infraciliature of Apoamphileptus robertsi nov. spec., isolated from a shrimp-farming pond near Qingdao (Tsingtao), China, have been investigated using living observations and the protargol silver impregnation method. The diagnosis for this new species is: Apoamphileptus 90-180 x 30-60 microm in vivo, body elongate pyriform-shaped and slightly flattened; with one cross-striated band along the cytostome; 2-6 (generally 4) large macronuclear nodules, one micronucleus; 33-43 right somatic kineties; left side 6-8 kineties; two extra anterior fragments on left side; about 13 contractile vacuoles dispersed throughout whole body; extrusomes absent or not recognizable; marine habitat. Some morphologically related morphotypes are discussed and tabulated. Regarding the pattern of infraciliature and other morphological features, the well-described fresh-water species, Amphileptus claparedii Stein, 1867 is believed to be a member of this new genus, hence a new combination is suggested: Apoamphileptus claparedii (Stein, 1867) nov. comb.

Animals↗