Designed eggs containing conjugated linoleic acids and omega-3 polyunsaturated fatty acids.
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Biomedical subjects
Publications and source records attributed to S Feng.
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OBJECTIVE: The purpose of this study was to anatomically confirm that anterior shoulder injection could result in penetration of the anterior stabilizing structures of the glenohumeral joint and to advocate the use of a tailored approach to MR arthrography based on presenting symptoms. CONCLUSION: A tailored approach to MR arthrography may be a useful way to isolate expected pathology in the shoulder and limit confounding findings related to the performance of the procedure.
OBJECTIVE: To explore the genetic model of systemic lupus erythematosus(SLE). METHODS: Complex segregation analysis was performed by using statistical analysis for genetic epidemiology-REGTL(SAGE-REGTL). The genetic model and gene frequency were estimated. 300 pedigrees with SLE were collected from 300 patients as probands. RESULTS: The complex segregation analysis found the genetic model of SLE to be additive,the gene frequency 0.336. The authors believe the possibility of some different modes coexisting under different circumstances. The genetic effect on young man is stronger than that on old one. CONCLUSION: This study suggests that the genetic mode of SLE could be the major gene trait, and additive mode is the best fitted one.
OBJECTIVE: To investigate the influence and mechanism of incidence of atrioventricular block (AVB) treated with thrombolytic therapy in acute inferior myocardial infarction (AIMI). METHODS: A total of 46 patients with AIMI were divided into the thrombolytic group (n = 23) and the non-thrombolytic group (n = 23). Intravenous or intracoronary urokinase was given to the former group. We observed the advancing courses of AVB, and further assessed the relationship between occurrence of AVB and stenosis of infarct-related artery (IRA) with coronary angiography. RESULTS: Two cases died of III degree AVB in the non-thrombolytic group, but none was found in the thrombolytic group. The occurrence rate of AVB was similar in both groups; but that of III degree AVB was much lower in the thrombolytic group (4 cases) than that in the non-thrombolytic group (11 cases, P < 0.05), and the duration of AVB decreased from 201 +/- 113 hours to 102 +/- 60 hours after thrombolytic therapy (P < 0.01), which was mainly due to the decrease of AVB in the vanishing interval, but not in the developing interval. The coronary angiography demonstrated that there were an increasing reperfusion flow and a decreasing coronary stenosis of the infarct-related artery after thrombolytic therapy. CONCLUSION: Thrombolytic therapy can reduce the incidence of severe AVB, shorten its duration and decrease the mortality by increasing the coronary reperfusion flow in the patients with AIMI.
With haloalkane dehalogenase gene (dhlA) of Xanthobacter autothophicus as a negative selection marker, a novel trans-inactivation system for transgenes in plants was developed. After the Arabidopsis plants were transformed with dhlA, one plant was shown dhlA post-transcriptional silencing by nuclear run-off transcriptional analysis. The Arabidopsis plants containing silencing locus were crossed to those efficiently expressed dhlA, referred as a homologous transgenic locus, and 96% of F1 plants became the homologous dhlA inactivated in trans. When the F1 plants were selfed, and the silencing locus and the homologous locus were separated in some progenies, 42 of the 200 progenies exhibited DhlA activity, and 158 no DhlA activity, and the proportion of the DhlA-expressing plants to the dhlA-silencing ones was 3.76 to 1, which suggested that the silencing locus inactivated in trans the homologous transgenic locus as a Mendelian dominant factor.
OBJECTIVE: To study the curative effect of transnasal medial canthopexy. METHODS: By a coronal or medial canthal incision, we applied transnasal medial canthopexy to repair medial canthal detachment. A total of 78 patients received the operation. RESULTS: Of them, 64 patients obtained satisfactory postoperative appearance with one operation; 6 patients obtained satisfactory results with two operations. The operation was unsuccessful in 8 patients. CONCLUSION: This method is one of the ideal methods of repairing medial canthal detachment, however its indications should be observed.
Disease-susceptible (C3H) and -resistant (B6) immunocompetent and immunodeficient (C3H-scid and B6-rag1) mice were examined up to 10 weeks after inoculation with Helicobacter bilis (a prototype species of proven virulence). Infection was monitored weekly by use of fecal culture, polymerase chain reaction (PCR) nucleic acid amplification, membrane extract enzyme-linked immunosorbent assay (ELISA), and histologic examination. All mice became infected by three to five weeks after inoculation, on the basis of results of culture and PCR analysis of feces. The PCR analysis was more sensitive than culture at determining infection status, particularly during early infection. None of the mice had evidence of disease by week 10. Immunoglobulin G seroconversion was detectable in C3H mice by week eight and in B6 mice by week nine. Results indicated that culture and PCR analysis are more sensitive than is membrane extract ELISA serologic testing for detecting early infection in individual mice, regardless of genotype or immune status. Results underscore the need for improved seroassays for this important group of murine pathogens.
OBJECTIVE: To investigate the expression of leukemia inhibitory factor (LIF) in the decidua of normal early pregnancy, threatened abortion and inevitable abortion. METHOD: We examined LIF gene expression in the above-mentioned decidua by a quantitative reverse transcription-polymerase chain reaction (RT-PCR) method, and also examined the serum pregesterone, human chorionic gonadotrapin (hCG) by radioimmunoassay in all cases. RESULTS: (1) Serum levels of pregesterone and hCG are: (91.5 +/- 27.2) nmol/L, (69.9 +/- 14.9) kU/L in normal early pregnancy; (88.4 +/- 24.7) nmol/L, (57.6 +/- 11.2) kU/L in threatened abortion respectively. There was no difference in the levels of pregesterone and hCG between the two groups (P > 0.05). While serum pregesterone, hCG levels in inevitable group were (33.1 +/- 19.6) nmol/L, (10.3 +/- 3.2) kU/L respectively. Compared with normal early pregnancy and threatened abortion group, the levels of serum pregesterone and hCG reduced significantly (P < 0.05). (2) The expression of LIF in three groups: There was no statistically significant difference in the levels of LIF expression between the normal early pregnancy group (2.10 +/- 0.32) and threatened abortion (1.92 +/- 0.20) groups, while the levels of LIF expression in inevitable abortion group (0.7 +/- 0.06) was lower than those in normal early pregnancy group and threatened abortion group (P < 0.05, respectively). CONCLUSION: The reduction of LIFmRNA expression in the decidua of early pregnancy may decrease the serum pregesterone and hCG levels and cause inevitable abortion.
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BACKGROUND: Dendritic cells are potent antigen-presenting cells that bind allogeneic T cells. They are thus candidates for targeting immunoregulatory molecules to the alloreactive T cell compartment and suppressing the alloimmune response. METHOD: A dendritic cell line derived from the BALB/c mouse (H2d) was genetically modified to express the immunoregulatory molecule CTLA4-Ig. The ability of these dendritic cell transfectants to downregulate the alloimmune response was tested in an islet transplant model. Allogeneic C57Bl/6 (H2b) mice were rendered diabetic with streptozocin, and they received BALB/c islet (H2d) transplants. Mice were administered 25 million untransfected or CTLA4-Ig-transfected D2SC/1 cells i.v. on the day of islet transplantation and 6 days later[fnc]. RESULT: Mice treated with CTLA4-Ig-transfected D2SC/1 cells demonstrated prolonged allograft survival (mean = 20 days, median = 17 days, SD = 9.39) compared with mice treated with untransfected D2SC/1 cells (mean = 12 days, median = 11 days, SD=2.74) or untreated control mice (mean = 11 days, median = 11 days SD = 1.41). Third party allograft survival was not prolonged in mice receiving similar treatment. CONCLUSIONS: These results demonstrate that a genetically modified dendritic cell line can suppress the alloimmune response and prolong islet allograft survival in an allospecific manner. The findings also suggest that genetically modified dendritic cells may be useful in targeting alloreactive T cells and prolonging allograft survival.
Shear stress causes the platelet glycoprotein (Gp) Ib/IX/V to bind to von Willebrand factor, resulting in platelet adhesion. GpIb/IX/V also functions to stimulate transmembranous signaling, leading to platelet activation and the expression of a ligand-receptive GpIIb-IIIa complex. The highly conserved cytoplasmic domain of GpIbalpha binds directly to a dimeric 14-3-3 adapter protein zeta isoform. To explore structural determinants of GpIb/IX/V binding to 14-3-3zeta, the authors examined 14-3-3zeta interactions with GpIbalpha and GpIbbeta in heterologous cells and platelets. Truncations of GpIbalpha at amino acid 542 or 594, or deletions of residues 542 through 590, inhibited binding of 14-3-3zeta. Deletion of GpIbalpha from Trp(570) to Ser(590) eliminated 14-3-3zeta binding, and deletion of the sequence from Arg(542)-Trp(570) enhanced binding of 14-3-3zeta to GpIbalpha. All GpIbalpha mutations that eliminated GpIbalpha binding to the GST-14-3-3zeta fusion protein also eliminated GpIbbeta binding to the fusion protein. Forskolin treatment of Chinese hamster ovary cells expressing wild-type GpIbalpha/beta/IX resulted in the phosphorylation of GpIbbeta associated with enhanced binding of GpIbbeta to GST-14-3-3zeta fusion protein and increased 14-3-3zeta coimmunoprecipitated with GpIbalpha. When intact human platelets aggregated in response to 90 dynes/cm(2) shear stress, 14-3-3zeta disassociated from GpIbalpha. Prostacyclin treatment of platelets inhibited shear stress-induced aggregation and the release of 14-3-3zeta from GpIbalpha. These data demonstrate that amino acid residues in the cytoskeletal interaction domains of GpIbalpha regulate 14-3-3zeta binding to GpIbalpha/beta/IX, and suggest that protein kinase A-dependent phosphorylation of GpIbbeta enhances 14-3-3zeta binding to the GpIb/IX/V complex in human platelets. (Blood. 2000;95:551-557)
Experiments were conducted to determine the influence of basal lamina on the morphology of ovarian granulosa cells in vitro. Pure and intact basal lamina was isolated from the large preovulatory follicles of the chicken ovary and designated basal lamina of avian ovarian follicle (BLAOF). Examination of the isolated basal lamina with electron microscope revealed an ultrastructure that is similar to that of basal lamina in the intact ovarian follicle. Pieces of the intact basal lamina were attached to the bottom of 32 mm culture dishes (BLAOF-coated dishes) in which differentiated granulosa cells isolated from the largest preovulatory follicle or undifferentiated granulosa cells isolated from immature small yellow chicken ovarian follicles were cultured; uncoated dishes served as controls. Granulosa cells incubated on intact basal lamina assumed spherical shape, whereas granulosa cells incubated directly on plastic in control dishes became highly flattened. Interestingly, granulosa cells that attached to plastic close to BLAOF (in BLAOF-containing dishes) became rounded. The storage of BLAOF-coated culture dishes at 4 degrees C for 2 years had no apparent effect on its ability of the matrix material to induce changes in granulosa cell shape. Some components of the basal lamina could be solubilized with guanidine-HCl alone (fraction 1; 90-95% of total protein in BLAOF) with the remaining components solubilized with beta-mercaptoethanol containing guanidine-HCl (fraction 2; 5-10% of total protein in BLAOF). Differentiated and undifferentiated chicken granulosa cells became rounded when incubated in fraction 1-pre-coated wells; whereas those incubated directly on plastic in control wells were flattened. Similarly, when fraction 1 of solubilized basal lamina was added as liquid to incubation mixture, it caused both differentiated and undifferentiated granulosa cells to assume spherical shapes. The storage of fraction 1-coated culture dishes at 4 degrees C for 12 or more months had no apparent effect on its ability to influence granulosa cell shape. Fraction 1-induced changes in granulosa cell shape were similar to those observed for complete and intact basal lamina (BLAOF). These findings demonstrate that intact homologous basal lamina (BLAOF) or its solubilized (fluidized) form can induce normal (in vivo) morphology in granulosa cells. It is suggested that BLAOF or its solubilized form can be used to culture cells in experiments designed to examine the influence of the natural basal lamina microenvironment on cellular behavior and function.
Methods are described to establish distinct cell cultures from bovine placental cotyledon. The villous tissue of the bovine placental cotyledon is collected and dissociated with 0.125% trypsin. The cells are then cultured in three different media: a serum-free medium, a growth factor supplemented medium, and a medium with 10% serum. A polygonal cell line grew out of the serum-containing medium, a fan-shaped cell line grew out of the serum-free medium, and an epitheloid cell line grew out of the growth factor supplemented medium. These cells maintained their morphology when grown in serum containing medium. The preference of distinct cells for different media in vitro reflects the in vivo physiological regulation of these cells. These distinct cultures re ideal to study the extrinsic and interactive factors in bovine placenta.
Outer surface protein (Osp) C immune pressure during persistent infection with Borrelia burgdorferi was examined in relation to genetic variation of ospC. Mice were infected with clonal B. burgdorferi sensu stricto (s.s.) N40 or B. afzelii PKo and then were hyperimmunized with homologous recombinant OspC or with decorin-binding protein A (DbpA) (controls). After 6 months, B. burgdorferi isolates were subjected to restriction enzyme analysis of the amplified ospC genes and were found to have no differences among 9 B. burgdorferi s.s. N40 and 9 B. afzelii PKo isolates from OspC hyperimmune mice or among 10 B. burgdorferi s.s. N40 and 10 B. afzelii PKo isolates from DbpA hyperimmune mice, compared with input inocula. Comparison of gene sequences among 4 B. burgdorferi s.s. N40 and 9 B. afzelii PKo isolates from OspC-immunized mice revealed no ospC variation from input inocula. Variation in ospC among B. burgdorferi isolates and species during chronic infection is not likely to be an important mechanism for immune evasion.
A simple extraction procedure for delta9-tetrahydrocannabinol (delta9-THC) and its metabolites from various biological specimens was developed based on immunoaffinity chromatography. Using the affinity resin prepared by immobilization of THC antibody onto cyanogen bromide-activated Sepharose 4B, delta9-THC and its major metabolites including 11-nor-delta9-THC-9-carboxylic acid (delta9-THCCOOH), 11-hydroxy-delta9-THC (11-OH-delta9-THC), and 8beta,11-dihydroxy-delta9-THC (8beta,11-diOH-delta9-THC) were extracted simultaneously from plasma or urine after enzyme hydrolysis. The samples were derivatized as TMS derivatives and analyzed by gas chromatography-mass spectrometry in EI mode with SIM monitoring. Greater than 87% extraction recovery of the four analytes was obtained from both plasma and urine at 5 and 50 ng/mL concentration levels. The method was also used for meconium analysis with some modification. The extraction recovery from meconium, however, was lower than that of plasma and urine, ranging from 52 to 72% at the 10-ng/g level. All compounds showed good linearity within the tested ranges up to 100 ng/mL (g). The limits of detection ranged from 0.5 to 2.5 ng/mL in plasma and urine, and from 1.0 to 2.5 ng/g in meconium. Analysis of 24 meconium specimens showed that 11-OH-delta9-THC is indeed an important metabolite in meconium.
We present a model of isodiffracting single-cycle and few-cycle ultrashort electromagnetic pulses. The model is based on exact solutions of the time-dependent paraxial wave equation with space-time coupling effects included. The spatiotemporal structure of these pulses is characterized by a scaling parameter which relates off-axis pulse shapes to the axial temporal waveforms. Depending on the spectrum a pulse may transform itself from a single-cycle pulse to a multicycle pulse along the radial coordinate. This model is also used to describe recirculating pulses in a curved mirror cavity resonator. The Gouy phase shift contributes an absolute phase that results in a pulse-to-pulse temporal instability.
Lipopolysaccharide (LPS) is one of the main virulence factors of gram-negative bacteria. The LPS from Campylobacter spp. has endotoxic properties and has been shown to play a role in adhesion. We previously cloned a gene cluster (wla) which is involved in the synthesis of the Campylobacter jejuni 81116 LPS molecule. Sequence alignment of the first gene in this cluster indicated similarity with galE genes. These genes encode a UDP-glucose 4-epimerase, which catalyzes the interconversion of UDP-galactose and UDP-glucose. A Salmonella galE mutant was transformed with the galE gene from C. jejuni. The LPS analysis of wild-type, galE, and complemented galE Salmonella strains showed that the C. jejuni galE gene could restore the smooth wild-type Salmonella LPS. A UDP-glucose 4-epimerase assay was used to demonstrate that the galE gene from C. jejuni encoded this epimerase. We constructed a C. jejuni galE mutant which expressed a lipid A-core molecule of reduced molecular weight that did not react with antiserum raised against the parental strain. These results show an essential role for the galE gene in the synthesis of C. jejuni LPS. The galE mutant also showed a reduction in its ability to adhere to and invade INT407 cells. However, it was still able to colonize chickens to the same level as the wild-type strain. The serum resistance and hemolytic activity of this mutant were not changed compared to the parent strain. The ability of the mutant to take up DNA and integrate it in its genome was reduced 20-fold. These results show that LPS of C. jejuni is an important virulence factor.