Search PubMed⌕ Search

Biomedical subjects

J Lin

Publications and source records attributed to J Lin.

At least 127 records · Page 7Linked to original sources

Two-stage exchange hip arthroplasty for deep infection.

Although the risk of infection after total hip arthroplasty has decreased over the last three decades with the use of prophylactic antibiotics, laminar airflow operating rooms and whole-body exhaust suites, deep infection after total hip arthroplasty remains a serious complication. Significant morbidity to the patient and the cost to the health care system remain. During this period of time, diagnostic techniques also have improved including the use of polymerase chain reaction amplification. Treatment options now include: suppressive antibiotics, irrigation and debridement with retention of components, one-stage reimplantation, two-stage reimplantation, and salvage procedures. Based on the medical literature, the successful eradication of a total joint replacement infection with a two-stage reimplantation protocol is over 90% while the success rate with a one-stage protocol is approximately 80%. These success rates may decline however as the prevalence of antibiotic resistant organisms increases. Current controversies regarding two-stage reimplantation protocols include: duration of intravenous antibiotic therapy, timing of the reimplantation, the use of allograft bone in the reconstruction, the choice of fixation (cement versus cementless), and the use of antibiotic-loaded cement spacers.

Anti-Bacterial Agents↗

Intraarticular osteoid osteoma: sonographic findings in three patients with radiographic, CT, and MR imaging correlation.

OBJECTIVE: Intraarticular osteoid osteoma often has subtle radiographic findings and nonspecific clinical features; further diagnostic workup of unexplained joint pain may involve musculoskeletal sonography. We describe the sonographic features of intraarticular osteoid osteoma in three consecutive patients with radiographic, CT, and MR imaging correlation. CONCLUSION: The sonographic findings of painful cortical irregularity and focal synovitis should raise the possibility of intraarticular osteoid osteoma, prompting the search for characteristic findings on correlative imaging studies.

Adult↗

A genome scan for type 2 diabetes susceptibility loci in a genetically isolated population.

A total of 896 individuals of Ashkenazi Jewish descent were ascertained in Israel from 267 multiplex families, including 472 sib-pairs affected with type 2 diabetes. A genome-wide scan with average marker spacing of 9.5 cM revealed five regions on four chromosomes (4q, 8q, 14q, and 20q) that exhibited nominal evidence for linkage (P < 0.05). The highest observed nonparametric linkage Z score was 2.41 (equivalent to a logarithm of odds score of 1.26) at marker D4S1501. A maximal signal, with a Z score of 2.05, was observed on chromosome 20 near marker D20S195, and another on 20p near marker D20S103 (Z 1.80). A single marker on chromosome 8 (D8S593) and two adjacent markers on chromosome 14 (D14S749 and D14S605) also attained evidence of linkage. To explore the hypothesis that the signals on chromosomes 4 and 20 are differentially attributable to variation in BMI or age of onset, an ordered subset analysis was conducted. This analysis revealed that only when the families were ranked by BMI (in increasing order) did a subset attain nominal significance, and only for chromosome 4. The findings reported here lend credence to the hypothesis, now supported by four studies of Caucasian populations and most recently by a combined analysis of 1,852 pedigrees, that a type 2 diabetes susceptibility locus resides on chromosome 20q. This population, because of its unique genetic attributes, may facilitate identification of this and other genes contributing to type 2 diabetes.

Body Mass Index↗

Mutations in the coding region of the neurogenin 3 gene (NEUROG3) are not a common cause of maturity-onset diabetes of the young in Japanese subjects.

Mutations in transcription factors that play a role in the development of the endocrine pancreas, such as insulin promoter factor-1 and NeuroD1/BETA2, have been associated with diabetes. Cell type-specific members of the basic helix-loop-helix (bHLH) family of transcription factors play essential roles in the development and maintenance of many differentiated cell types, including pancreatic beta-cells. Neurogenin 3 is a bHLH transcription factor that is expressed in the developing central nervous system and the embryonic pancreas. Mice lacking this transcription factor fail to develop any islet endocrine cells and die postnatally from diabetes. Because neurogenin 3 is required for the development of beta-cells and other pancreatic islet cell types, we considered it a candidate diabetes gene. We screened the coding region of the human neurogenin 3 gene (NEUROG3) for mutations in a group of unrelated Japanese subjects with maturity-onset diabetes of the young (MODY). We found three sequence variants: a deletion of 2-bp in the 5'-untranslated region (NEUROG3-g.-44-45delCA), a G-to-A substitution in codon 167 (g.499G/ A), resulting in a Gly-to-Arg replacement (G/R167), and a T-to-C substitution in codon 199 (g.596T/C), resulting in a Phe/Ser polymorphism F/S199. These polymorphisms were not associated with MODY, thereby suggesting that mutations in NEUROG3 are not a common cause of MODY in Japanese patients.

Amino Acid Substitution↗

Regulation of the pancreatic pro-endocrine gene neurogenin3.

Neurogenin3 (ngn3), a basic helix-loop-helix (bHLH) transcription factor, functions as a pro-endocrine factor in the developing pancreas: by itself, it is sufficient to force undifferentiated pancreatic epithelial cells to become islet cells. Because ngn3 expression determines which precursor cells will differentiate into islet cells, the signals that regulate ngn3 expression control islet cell formation. To investigate the factors that control ngn3 gene expression, we mapped the human and mouse ngn3 promoters and delineated transcriptionally active sequences within the human promoter. Surprisingly, the human ngn3 promoter drives transcription in all cell lines tested, including fibroblast cell lines. In contrast, in transgenic animals the promoter drives expression specifically in regions of ngn3 expression in the developing pancreas and gut; and the addition of distal sequences greatly enhances transgene expression. Within the distal enhancer, binding sites for several pancreatic transcription factors, including hepatocyte nuclear factor (HNF)-1 and HNF-3, form a tight cluster. HES1, an inhibitory bHLH factor activated by Notch signaling, binds to the proximal promoter and specifically blocks promoter activity. Together with previous genetic data, these results suggest a model in which the ngn3 gene is activated by the coordinated activities of several pancreatic transcription factors and inhibited by Notch signaling through HES1.

Animals↗

[Expression of human brain derived neurotrophic factor gene in E. coli].

The primers specific for the full-length BDNF coding sequence was designed and synthesized. The BDNF coding sequence was directly amplified from human genomic DNA by using PCR and inserted into vector pGEM-3Zf(+). The recombinant DNA was transformed into the host cells JM109 to obtain the positive clone pGEMBF18. The restriction enzyme analysis and DNA sequence detection confirmed that the inserted fragment of clone pGEMBF18 is the full-length BDNF coding sequence. The hBDNF DNA fragment was recovered from the clone pGEMBF18 and ligated with prokaryotic expression vector pGEX-5T to construct the recombinant expression plasmid p5TBF34. The E. coli JM109 transformed with p5TBF34 was induced with IPTG. A new protein band with apparent molecular weight 43 kDa was detected in the lysate of the transformed cell by using SDS-PAGE. The result of western hybridization showed that this fusion protein reacted specifically to the antibodies to human BDNF. The amount of the soluble fusion protein was about 503.04 mg/L lysate, 7.53% of total bacterial soluble protein of transformed cells, estimated by absorbance scanning of SDS-PAGE and protein quantitation.

Brain-Derived Neurotrophic Factor↗

Multiple myeloma associated with extramedullary plasmacytoma causing nerve root compression: a case report.

Multiple myeloma associated with extramedullary plasmacytoma at initial presentation is rare. We describe a 45-year-old female patient with an initial presentation of low back pain and right side L5, S1 radiculopathy. There was no evidence of vertebral involvement but an epidural tumor was found later during neurosurgical intervention. The final diagnosis was immunoglobulin G, kappa multiple myeloma complicated with spinal root compression by an extramedullary plasmacytoma. No osteolytic lesion was noted over the length of the spine. Pathology revealed high-grade plasmablastic myeloma. During the clinical course, the patient was refractory to induction chemotherapy, and there was progressive deterioration of renal function. Urinary tract infection by Morganella morganii and pulmonary infection of unknown cause developed 5 months later, and the patient died.

Female↗

Formation of unusual glutamate conjugates of 1-[3-(aminomethyl)phenyl]-N-[3-fluoro-2'-(methylsulfonyl)-[1,1'-biphenyl]-4-yl]-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (DPC 423) and its analogs: the role of gamma-glutamyltranspeptidase in the biotransformation of benzylamines.

The role of gamma-glutamyltranspeptidase (GGT) in transferring glutamate from endogenous glutathione (GSH) to the benzylamine moiety of a compound, such as 1-[3-(aminomethyl)phenyl]-N-[3-fluoro-2'-(methylsulfonyl)-[1,1'-biphenyl]-4-yl]-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (DPC 423), is described. Studies were performed with structurally related analogs of DPC 423 to demonstrate that this type of reaction was common to compounds possessing a benzylamine group. Synthesizing appropriate standards and confirming by liquid chromatography (LC)/mass spectroscopy and LC/NMR made unambiguous assignments of the structures of glutamate conjugates of DPC 423. The use of stable isotope-labeled GSH for metabolism studies has not been described before. In the present study, we report the novel use of deuterated GSH in conjunction with mass spectral analysis to demonstrate the glutamate transfer to the benzylamines in the presence of GGT. To further demonstrate that the alpha protons on the benzylamines and glutamate (as part of glutathione) were unaffected during the transpeptidation, these protons were replaced with deuterium. Acivicin (AT-125), a potent and selective inhibitor of GGT, was used to abolish the formation of the glutamate conjugates of DPC 423 in vitro and in vivo. This provided further evidence of the role of GGT in forming the glutamate conjugates of benzylamines. This study demonstrated conclusively that GGT was responsible for mediating the transfer of glutamic acid from GSH to the benzylamine moiety of a series of structurally related compounds.

Animals↗

[Ectopic expression of human brain derived neurotrophic factor gene in fibroblasts].

The full-length sequence encoding hBDNF was inserted down into the enhancer-promotor regulatory element of Colia1 to construct minigene Colia1-BDNF. The recombinant eukaryotic expression plasmid pSCEPBFCAT was transfected into human fetal tendon fibroblasts in culture to realize ectopic expression of hBDNF gene in fibroblasts. The results of immuno-dot blot, Elisa and Western hybridization confirm that the expression protein with apparent molecular weight 27 kDa in pSCEPBFCAT transfected fibroblasts possesses antigen activity specific for the antibodies to BDNF.

Brain-Derived Neurotrophic Factor↗

[The effect of composite Radix Salviae Militiorrhizae injection on myocyte apoptosis in acute myocardial infarction of rabbits].

OBJECTIVE: To study the effect of composite Radix Salviae Militiorrhizae injectiion on myocyte apoptosis in experimental acute myocardial infarction of rabbits. METHODS: The models of acute myocardial infarction were made with rabbits. The method of terminal deoxynucleotidyl transferase mediated dUTP nick end labeling was used to explore myocardial cell apoptosis in different injury area of acute myocardial infarction. The activities of plasma superoxide dismurase and the contents of serum malonic aldehyde were determined. RESULTS: When rabbits were in the condition of acute myocardial infarction, there were myocyte apoptosis in the area of ischemia reperfusion injury and the area of infarction. The number of myocyte apoptosis and the myocyte rate in control group and composite Radix Salviae Militiorrhizae injectiion treated group were higher than in sham-operated group (P < 0.001). In the area of ischemia reperfusion injury the number of myocyte apoptosis and the myocyte rate in composite salvia militiorrhiza-treated group were lower than in control group (P < 0.05). The activity of plasma superoxide dismurase in composite salvia militiorrhiza-treated group was higher than in control group (P < 0.05), but lower than in sham-orerated group (P < 0.001). The content of serum malonic aldehyde in composite Radix Salviae Militiorrhizae injectiion treated group were lower than in control group (P < 0.05), but higher than in sham-operated group (P < 0.01). CONCLUSION: Composite Radix Salviae Militiorrhizae injectiion could reduce the number of myocyte apoptosis in the area of ischemia reperfusion injury, which maybe explained by the increase of the activity of plasma superoxide dismurase and the decrease of the contents of serum malonic aldehyde.

Animals↗

[Effects of metformin on hyperinsulinemic anovulation].

OBJECTIVE: To investigate the effects of metformin on serum testosterone (T) levels and ovulation in hyperinsulinemic women. METHODS: Twenty-nine patients with hyperinsulinemic anovulation were treated with metformin for 12 weeks. Among them 19 had history of clomiphene(CC) treatment with 11 cases failure. CC was given again after one month of metformin treatment. Serum T, luteinizing hormone, follicle-stimulating hormone, insulin(Ins) levels were measured after 4 weeks of treatment. Basic body temperature was also observed. RESULTS: Serum T and Ins levels declined significantly after 4 weeks of metformin treatment [(2.7 +/- 1.6) nmol/L Vs (1.9 +/- 1.0) nmol/L, (49.2 +/- 34.1) mU/L Vs (25.3 +/- 23.9) mU/L, P < 0.05, P < 0.05 respectively]. Eight cases ovulated spontaneously and 8 cases with history of CC failure became ovulatory during CC treatment. CONCLUSIONS: Metformin is effective for suppressing serum T levels and improving the outcome of ovulation.

Adult↗

Application of ultrasonic scalpel in gynecologic operative laparoscopy.

OBJECTIVE: To investigate the applied value of the ultrasonic scalpel in gynecologic operative laparoscopy. METHODS: Gynecologic operations were performed using the ultrasonic scalpel under laparoscopy. Operative bleeding and time, perioperative body temperature and hemogram, and tissue damage were observed. RESULTS: Forty-two cases of benign gynecologic diseases were treated with the ultrasonic scalpel under laparoscopy. Among them, there were 4 hysterectomies, 9 ovarian cystectomies, 18 salpingotomies, 4 ectopic pregnancies, 3 myomectomies, 3 adhesiolysis and 1 adnexectomy. The amount of operative bleeding, operating time and the tissue injury were related to the type of operation. The minimual operative bleeding amount, operating time, depth of tissue necrosis, tissue injury score and fibrin deposition score were 24.77 +/- 4.71 ml, 23.39 +/- 3.01 min, 0.22 +/- 0.10 mm, 0.98 +/- 0.21 and 0.38 +/- 0.26, respectively. The maximal operative bleeding amount, operating time, depth of tissue necrosis, tissue injury score and fibrin deposition score were 166.7 +/- 47.18 ml, 127.2 +/- 16.99 min, 0.35 +/- 0.20 mm, 1.25 +/- 0.20 and 0.81 +/- 0.29, respectively. The levels of body temperature, white blood cells and hemoglobin before and after the operations were not statistically different (P > 0.05) except for hysterectomy (P < 0.05). CONCLUSION: The ultrasonic scalpel can be safely applied for gynecologic operative laparoscopy and should be used widely.

Blood Loss, Surgical↗

[Effect of Cordyceps sinensis on inhibiting systemic lupus erythematosus in MRL 1pr/1pr mice (correction of rats)].

OBJECTIVE: To study the effect of Cordyceps sinensis on inhibiting systemic lupus erythematosus (SLE) in MRL 1pr/1pr rats. METHODS: The evalutions of lymphnoditis, proteinuria, kidney function and plasma antibody were adopted in MRL 1pr/1pr rats. RESULTS: Cordyceps sinensis could inhibit lymphadenectasis, induce the level of proteinuria and anti-ds-DNA antibody in plasma, and improve kidney function in SLE rats. CONCLUSION: Codyceps sinensis played an role on SLE rats.

Animals↗

[Vitreoretinal surgery with intraocular C3F8 tamponade for retinal detachment due to macular hole without face-down positioning].

OBJECTIVE: To evaluate the effectiveness of vitreoretinal surgery with 16% perfluoropropane (C3F8) tamponade without face-down positioning in treatment of retinal detachment due to macular hole. METHODS: Twenty-seven consecutive eyes in 27 patients with retinal detachment due to myopic macular hole underwent closed vitrectomy, membrane peeling, gas-fluid exchange with C3F8 tamponade in the whole vitreous chamber. In 3 eyes, phacoemulsification was performed, and 2 of them received intraocular lens implantation. Postoperatively, except avoiding the supine position, the body position was not restricted. RESULTS: Twenty-one cases (78%) obtained successful retinal reattachment without the postoperative face-down positioning. In another 6 cases, because of the relatively quick absorption of the gas, the white macular hole and the subretinal proliferation, the operation was not successful, the hole being not sealed and the retinal detachment at the lower part still existing. In the 3 cases with quick absorption of the gas, on the 10th day after the operation, the body position was changed into a face-down one. In 2 of them, the retinal reattachment occurred. After > 6 months of follow-up, the retinal reattachment remain the same in 22 cases (81%), the macular hole was healed, and the visual acuity was elevated to > or = 0.1 in 19 cases. The main complications were lens opacity in 6 cases (31%), temporary elevation of intraocular pressure in 3 cases (11%). CONCLUSION: Use the methods for the treatment of macular hole and retinal detachment mentioned above may obtain relatively good therapeutic results, particularly suitable for senile and unhealthy cases.

Aged↗

[Primary research about reconstruction of cornea in three-dimensional collagen gel in vitro].

OBJECTIVE: To research the reconstruction of cornea in three-dimensional culture. METHODS: Using primary cultured corneal epithelial cells, stromal cells and endothelial cells rebuilt a corneal structure in three-dimensional collagen gel reconstruction system. The artificial corneal transparency was examined by a slit-lamp microscope. The biological characters of cells were tested by routine pathologic and transmission electron microscopic technology. RESULTS: The reconstructed corneal tissue formed three layers. The epithelial cell layer was two or three cell thickness. The endothelial cells formed a single layer. The stromal cells were diffuse in distribution in the collagen gel. The cells had proliferative ability and capability of producing collagen. CONCLUSION: The regular and transparent corneal structure can be rebuilt by tissue engineering technology.

Cells, Cultured↗

[A study on susceptibility of different layers of rabbit retina to ocular hypertension].

OBJECTIVE: To investigate the histological damage and its degrees of different layers of rabbit retina induced by ocular hypertension. METHODS: The intraocular pressure (IOP) was elevated by intracameral injection of 0.10 - 0.15 ml of 2% methylcellulose in sixteen gray rabbits. The rabbit eyes were enucleated, fixed, and paraffin-embedded. For histological evaluation, the slides were stained with hematoxylin-eosin, examined by light microscopic and computer automatic image analysis. RESULTS: The quantitative analysis indicated that all of the retinal layers have different degrees of histopathological damage. Among them, the retinal ganglion cells (RGCs) and retinal nerve fiber layer (RNFL) were most severely damaged, with the decrease rate of 74.3% and 61.9%, respectively. The decrease rates of other retinal layers were as follows: the retinal inner layer, 42.4%; the whole sensory layer of the retina, 35.0% and the outer layer, 24.2%. We also found a significant correlation between RGCs loss and RNFL thinning (r = 0.68, P < 0.01), demonstrating a strong correlation between IOP level and RNFL thickness (F = 8.97, P < 0.01). CONCLUSION: All of the anatomic layers of retina can suffer from degeneration and atrophy at different degrees.

Animals↗