Search PubMed⌕ Search

Biomedical subjects

J J Lin

Publications and source records attributed to J J Lin.

233 records · Page 13Linked to original sources
PubMed1976

Biosynthesis and assembly of envelope lipoprotein in a glycerol-requiring mutant of Salmonella typhimurium.

A glycerol-requiring mutant of Salmonella typhimurium was used in a study of the biosynthesis and assembly of a structural lipoprotein in the cell envelope of gram-negative bacteria. Upon removal of glycerol from the growth medium, the biosynthesis of lipoprotein, as measured by radioactive arginine incorporation, was reduced by the same extent as that of other envelope proteins, the cumulative incorporation of arginine being 20% of that of the unstarved control cells. However, the incorporation of radioactive palmitate into lipoprotein was more severely curtailed after glycerol starvation, the cumulative rate of which was 8% of that observed in the unstarved cells. It was further observed that the lipoprotein synthesized in the glycerol-starved cells was more enriched in unmodified cysteine, which is known to be the N-terminal amino acid of lipoprotein, than that synthesized in the unstarved cells. We conclude that the synthesis of the apoprotein portion of Braun's lipoprotein proceeds independently of the attachment of diglyceride to the sulfhydryl group of the N-terminal cysteine and may, in fact, precede the incorporation of the diglyceride moiety.

Amino Acids↗
PubMed1976

Escherichia coli mutants altered in murein lipoprotein.

Mutants with alterations in the structure, biosynthesis, or assembly of murein lipoprotein were selected by a procedure based on radiation suicide of wild-type organisms by [3H]arginine under conditions where the radioactive arginine was preferentially incorporated into lipoprotein. Further screening for the potential mutants among the survivors of [3H]arginine suicide was carried out by using a sensitive immunodiffusion test, followed by radioactive double-labeling experiments. Three mutants were obtained and partially characterized.

Alanine↗
PubMedDate not supplied

Changes in cell shape and actin distribution induced by constant electric fields.

The development of motility in cultured cells is usually associated with a polarization of the cell shape. In particular, the leading edge of the cell is extended into a lamella which acts as a locus for the elaboration of cell processes and for the formation of cell-substrate contacts and, at the opposite end, retraction fibres often extend beyond the trailing edge of the cell. The alignment of microfilament bundles (stress fibres) along the direction of migration and the presence of a band of actin at the leading edge of the cell suggest an involvement of this protein in the motile process. The direction of growth and orientation of various cell types in tissue culture can be influenced by externally applied d.c. electric fields but the effect of the field on cellular motile activities is unknown. Here we describe a galvanotropic response of cultured Xenopus epithelial cells. At a field strength of 5 V cm-1 these cells elongate perpendicularly with respect to the field. The anodal side of the cell retracts and both the ends and cathodal edge become active in the extension of ruffling lamellipodia. In parallel with the change in the cell axis, stress fibres are oriented perpendicularly to the field, and a band of actin is associated with the lamellae at the cathodal edge and at the ends of the cell.

Actins↗
PubMedDate not supplied

Pseudomalignant tumor after biopsy of periostitis.

Periosteal reaction is a commonly encountered radiographic finding. Differential diagnoses include trauma, infection, and neoplasia. Biopsy may be necessary for the definitive diagnosis. Surgical trauma to an inflamed periosteum can stimulate a rapid and tremendous bone-forming response.

Biopsy↗
PubMedDate not supplied

Gene cloning, expression and vaccine testing of Schistosoma japonicum SjFABP.

A 600 bp DNA fragment was amplified by PCR from an adult Schistosoma japonicum cDNA library. Sequence analysis confirmed that this fragment contained an S. japonicum Chinese mainland strain fatty acid binding protein (Sj14FABP) gene. This gene was subsequently expressed in Escherichia coli (E. coli) and in Baculovirus/silkworm systems. The recombinant protein from E. coli was a 41 kDa GST fusion protein (rSj14/GST), which could be purified by glutathione agarose affinity chromatography, with a yield of 25 mg/L E. coli culture. The recombinant protein from the Baculovirus/silkworm system was an 18 kDa fusion protein (rSj14/His), which could be purified by Ni-NTA resin chromatography column with a yield of 3.5 mg per silkworm larva. Both rSj14/GST and rSj14/His could be recognized by S. japonicum-infected mouse sera and anti-rSj14/GST mouse sera in Western blotting. The purified recombinant protein was immunogenic in mice, rats and sheep, and 34.3%, 31.9% and 59.2% worm reductions, respectively, were obtained in vaccinated Kunming mice, Wistar rats and sheep vaccinated with Sj14/GST, compared to non-vaccinated control groups. Worm reductions of 48.8% and 49.0% were recorded in Balb/c mice immunized with Sj14/His, compared to non-vaccinated and BCG-vaccinated groups, respectively. These results indicate that rSj14FABP is a promising candidate vaccine for schistosomiasis japonica, particularly as in the rat and sheep vaccination experiments, no adjuvant was used.

Amino Acid Sequence↗
PubMedDate not supplied

The effect of antiplatelet therapy on the incidence of carotid plaque hemorrhage.

Hemorrhage into the carotid atheroma has recently been gaining attention with respect to the pathophysiology of cerebrovascular disease. Many patients are currently receiving platelet agents for various vascular diseases. Some researchers have postulated that antiplatelet therapy may be detrimental by possibly inducing intraplaque hemorrhage or by increasing preexisting hemorrhage. This retrospective study was undertaken to determine if the use of antiplatelet therapy increases the incidence of carotid plaque hemorrhage. Ninety-five consecutive carotid endarterectomies were performed and the atheromas examined microscopically for intraplaque hemorrhage. The atheromas were divided into two groups; those from patients receiving preoperative antiplatelet therapy and those who were not. Forty-five atheromas were removed from patients receiving preoperative antiplatelet therapy; 39 (87%) of these demonstrated intraplaque hemorrhage. Of the 50 atheromas which were removed from patients not receiving preoperative therapy, 45 (90%) showed intraplaque hemorrhage. We conclude that antiplatelet therapy does not increase the incidence of carotid plaque hemorrhage.

Aged↗
PubMedDate not supplied

Correlations between plasminogen activator inhibitor-1 and peritoneal transport in pediatric CCPD patients.

OBJECTIVE: Plasminogen activator inhibitor-1 (PAI-1) is an important regulator of plasminogen activators and has been shown to be involved in the accumulation of extracellular matrix (ECM) in various tissues. Since peritoneal ECM is a resistance site for peritoneal transport, the production and release of PAI-1 in the peritoneum may affect the peritoneal transport of water and small solutes. DESIGN: The linear correlations between the dialysate PAI-1 levels and the variables of peritoneal transport during peritoneal equilibration tests (PET) were examined. SETTING: A tertiary university hospital. PATIENTS: Six stable pediatric patients (age 10.8 +/- 4 years) undergoing continuous cycler-assisted peritoneal dialysis were included. INTERVENTIONS: None. RESULTS: All data are mean +/- SD. There was a positive correlation between the infused volume and the net ultrafiltration (UF, 198 +/- 127 mL, r = 0.82, p < 0.05). The dialysate PAI-1 levels increased during the dwell time (2.44 +/- 2.23 ng/mL or 2.46 +/- 1.72 micrograms at 4 hours vs 0.04 +/- 0.1 ng/mL or 0.04 +/- 0.09 micrograms at 0 hour, p < 0.05). The saturation indices (dialysate/plasma ratio) of PAI-1 and albumin at 4 hours were 1.05 +/- 1.21 and 0.028 +/- 0.004, respectively. The changes from 0 hour dwell to 4 hour dwell in the dialysate PAI-1 concentration (PAI4-0, 2.4 +/- 2.2 ng/mL) or amount corrected to body surface area (APAI4-0/BSA, 2.61 +/- 2.11 micrograms/m2) negatively correlated with UF or UF/body surface area and positively correlated with the number of episodes of peritonitis. There was no correlation between PAI4-0,APAI4-0/BSA, or plasma PAI-1 concentration and the mass transfer coefficient and clearance of either urea or creatinine. CONCLUSIONS: The elevated PAI-1 level during the PET was likely from the local production and release of PAI-1. It had an inverse relationship with the amount of ultrafiltration. Repeated inflammation of the peritoneum was associated with an increased production and release of PAI-1 into the peritoneum.

Adolescent↗
PubMedDate not supplied

Postinfectious encephalopathy in a child following Campylobacter jejuni enteritis.

We report a case of acute postinfectious encephalopathy in a child following Campylobacter jejuni enteritis. Serial MR scans showed lesions involving predominantly gray matter and the adjacent subcortical white matter--findings different from those in other immune-mediated disorders, such as systemic lupus erythematosus, in which either white or gray matter may be involved, and acute disseminated encephalomyelitis, in which white matter abnormalities predominate with involvement of the subcortical white matter.

Brain↗
PubMedDate not supplied

Changes in laminin during recovery from postischemic acute renal failure in rats.

Changes in the immunoreactivity of laminin have been demonstrated in a variety of tissues undergoing injury-regeneration process and during nephrogenesis. Studies in vitro revealed that laminin is important in many cellular functions such as growth, differentiation, and cell communication. This study examined the changes of laminin in the extracellular matrix (ECM) of proximal straight tubules (PST) in the outer stripe of the outer medulla after renal ischemia, an area where most morphological damage occurred. Anesthetized male Sprague-Dawley adult rats underwent a 30-min temporary occlusion of the left renal artery. The inulin clearance (Cin) of the postischemic left kidneys was significantly decreased at 30 min, 1 day, 2 days, and 5 days after the injury, and at 7 and 10 days after the injury it rose to a level not significantly different from the sham-operated controls. Using immunogold electron microscopy, the density of immunoreactive laminin (gold-conjugated laminin grains/micron2 ECM area) in PST where flattened PST cells were present was decreased at 1 day and 2 days, and at 5 days, a time when the renal function was still depressed, it returned to a level not significantly different from that in controls. These changes were not observed in those PST or proximal convoluted tubules in which morphology was intact. Further studies are needed to determine if these changes in laminin of damaged PST cells have any significant role during their recovery from the ischemic injury.

Acute Kidney Injury↗
PubMedDate not supplied

Comparing the effectiveness of different educational programs for patients with total knee arthroplasty.

PURPOSE: To compare the effects of preadmission and postadmission educational programs for patients with total knee arthroplasty. DESIGN: Quasiexperimental study. SAMPLE: 60 total knee arthroplasty patients. METHODS: Subjects in the experimental group received preadmission preoperative teaching with an instruction booklet during a preoperative outpatient clinic visit. Upon admission to the hospital, they were presented with an educational video tape. The control group received only postadmission preoperative teaching with the same instruction booklet and no video. PREADMISSION AND POSTADMISSION: Preoperative anxiety level, knowledge about postoperative care, exercise performance and postoperative recovery were used as outcome measures. FINDINGS: The research results found: 1. there was no significant difference between the two groups in reduction of preoperative anxiety score: 2. the experimental group had a significantly higher knowledge level than the control group; 3. the experimental group performed exercise more regularly and correctly than those in the control group; 4. the experimental group had greater flexion of the operative knee joint than the control group. CONCLUSION: Preadmission teaching with a videotape program and a health manual for patients with total knee arthroplasty is recommended. IMPLICATIONS FOR NURSING RESEARCH: More indicators such as postoperative pain and patient satisfaction can be used to investigate the effectiveness of intervention. In addition, increasing the sample size is recommended for future studies.

Aged↗