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11.
12.
Treatment of motoneuron degeneration by intracerebroventricular delivery of VEGF in a rat model of ALS 总被引:18,自引:0,他引:18
Storkebaum E Lambrechts D Dewerchin M Moreno-Murciano MP Appelmans S Oh H Van Damme P Rutten B Man WY De Mol M Wyns S Manka D Vermeulen K Van Den Bosch L Mertens N Schmitz C Robberecht W Conway EM Collen D Moons L Carmeliet P 《Nature neuroscience》2005,8(1):85-92
Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general. 相似文献
13.
Wiegerinck MA Roukema M van Kessel PH Mol BW 《Human reproduction (Oxford, England)》2005,20(8):2355-2358
BACKGROUND: Sutureless re-anastomosis per laparoscopy is an alternative for microsurgical re-anastomosis by laparotomy in the treatment of sterilized women with renewed child wish. Our aim was to compare pregnancy rates after both surgical techniques. METHODS: We performed a retrospective cohort study in which consecutive women who underwent sutureless re-anastomosis per laparoscopy were compared to women who underwent microsurgical re-anastomosis by laparotomy. Both procedures were performed in neighbouring hospitals in Northern-Brabant, The Netherlands, and women were matched for age. The primary outcome was time to ongoing pregnancy. RESULTS: Overall, we included 41 women who had sutureless re-anastomosis by laparoscopy, and 41 age-matched women who underwent microsurgical re-anastomosis by laparotomy. The number of women who conceived was 20 (15 ongoing pregnancies) in the sutureless laparoscopic group versus 26 (24 ongoing pregnancies) in the laparotomic group, a difference due to a longer follow-up period in the laparotomic group. Time to ongoing pregnancy was comparable in both groups (P=0.46), with 3 year cumulative ongoing pregnancy rates of 45 and 52% respectively. After adjustment for other prognostic factors, the fecundity rate ratio was 0.97 (95% CI 0.26-3.6), indicating a similar performance of the two techniques. CONCLUSION: The simplified stitchless laparoscopic procedure for reversal of tubal sterilization with the use of a tubal splint, clip fixation of the muscularis and fibrin glue resulted in a promising pregnancy rate, which was similar to the pregnancy rate obtained with the microsurgical re-anastomosis per laparotomy. 相似文献
14.
Human ovarian granulosa cells and follicular fluid indices: the relationship to oocyte maturity and fertilization in vitro 总被引:1,自引:0,他引:1
The study investigates the correlation between oocyte maturity and
fertilization and a variety of hormonal parameters in follicular fluid and
ovarian granulosa cells. A methodology for purification of granulosa cells
from contaminating blood cells is also established. A total of 63
follicular aspirates were collected at oocyte retrieval from 30 women
superovulated using the long luteinizing hormone- releasing hormone (LHRH
analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone,
testosterone and human chorionic gonadotrophin (HCG) were quantified in
follicular fluid and granulosa cells were immunostained for human chorionic
gonadotrophin. Immunopurification of granulosa cells from contaminating
blood cells was performed. HCG in follicular fluid was significantly high
in follicles yielding immature (grade 3) oocytes (P=0.002); there was no
correlation with fertilization. Aspirates from follicles containing mature
(grade 1) oocytes and oocytes that subsequently fertilized had
significantly more granulosa cells immunobound to HCG (P < 0.001,
P=0.02). Moreover, the immunomagnetic purification technique provided
>98% pure population of granulosa cells. The data demonstrate that HCG
in follicular fluid and on granulosa cells may help to predict oocyte
maturity and fertilization. Furthermore, immunomagnetic beads provide a
reliable procedure for the purification of ovarian granulosa cells.
相似文献
15.
Comparison of biotyping, ribotyping, and pulsed-field gel electrophoresis for investigation of a common-source outbreak of Burkholderia pickettii bacteremia.
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H Chetoui P Melin M J Struelens E Delhalle M M Nigo R De Ryck P De Mol 《Journal of clinical microbiology》1997,35(6):1398-1403
Over a 3-month period, six immunocompromised patients developed one or more episodes of Burkholderia pickettii bacteremia and/or catheter infection. Vials of a commercially available, "sterile" saline for injection which had been used for flushing the patients' indwelling intravenous devices were implicated as the common source of the organisms. No further cases were diagnosed once the use of this saline was discontinued. Twenty-six isolates, including 9 outbreak-related strains from case patients and contaminated saline as well as 17 control strains, were tested comparatively by biotyping, ribotyping with EcoRI and HindIII, and pulsed-field gel electrophoresis (PFGE) with SpeI. Macrorestriction analysis revealed nine PFGE groups and was more discriminating than ribotyping (seven ribotypes) and biotyping (two biovars). Among the outbreak-related isolates, one B. pickettii type was found by the three typing methods. Furthermore, PFGE was useful for subdividing ribotypes and for distinguishing isolates involved in the outbreak from all epidemiologically unrelated strains. 相似文献
16.
Marjolein P de Vries Lisette van den Bemt Karen Aretz Bart PA Thoonen Jean WM Muris Arnold DM Kester Sonja Cloosterman CP Onno van Schayck 《The British journal of general practice》2007,57(536):184-190
BACKGROUND: The efficacy of bed covers that are impermeable to house dust mites has been disputed. AIM: The aim of the present study was to investigate whether the combination of 'house dust mite impermeable' covers and a self-management plan, based on peak flow values and symptoms, leads to reduced use of inhaled corticosteroids (ICS) than self-management alone. DESIGN OF STUDY: Prospective, randomised, double blind, placebo-controlled trial. SETTING: Primary care in a south-eastern region of the Netherlands. METHOD: Asthma patients aged between 16 and 60 years with a house dust mite allergy requiring ICS were randomised to intervention and placebo groups. They were trained to use a self-management plan based on peak flow and symptoms. After a 3-month training period, the intervention commenced using house dust mite impermeable and placebo bed covers. The follow-up period was 2 years. Primary outcome was the use of ICS; secondary outcomes were peak expiratory flow parameters, asthma control, and symptoms. RESULTS: One hundred and twenty-six patients started the intervention with house dust mite impermeable or placebo bed covers. After 1 and 2 years, significant differences in allergen exposure were found between the intervention and control groups (P<0.001). No significant difference between the intervention and control groups was found in the dose of ICS (P = 0.08), morning peak flow (P = 0.52), peak flow variability (P = 0.36), dyspnoea (P = 0.46), wheezing (P = 0.77), or coughing (P = 0.41). There was no difference in asthma control between the intervention and control groups. CONCLUSION: House dust mite impermeable bed covers combined with self-management do not lead to reduced use of ICS compared with self-management alone. 相似文献
17.
The t(X;1)(p11.2;q21.2) translocation in papillary renal cell carcinoma fuses a novel gene PRCC to the TFE3 transcription factor gene 总被引:4,自引:2,他引:4
18.
Mol A van Lieshout MI Dam-de Veen CG Neuenschwander S Hoerstrup SP Baaijens FP Bouten CV 《Biomaterials》2005,26(16):3113-3121
In cardiovascular tissue engineering approaches, efficient seeding methods are essential. To achieve this and to save time, cells can be encapsulated in gels. Combining the advantages of a gel as a cell carrier with the advantages of a fiber-based scaffold, providing structural integrity to the developing tissue, might offer several advantages. In this study, seeding by using fibrin as a cell carrier is compared to the conventional static seeding method with regard to tissue development. Seeding with fibrin resulted in less loss of soluble collagen into the medium and a more mature extracellular matrix in a shorter period of time. The use of fibrin degradation inhibitors was shown to inhibit extracellular matrix formation, although it did not hamper cell proliferation. The use of fibrin as a cell carrier to seed cells into a fiber-based scaffold may represent a promising, timesaving approach in cardiovascular tissue engineering applications. 相似文献
19.
Catt SL; Sakkas D; Bizzaro D; Bianchi PG; Maxwell WM; Evans G 《Molecular human reproduction》1997,3(9):821-825
Controlling the sex of offspring by the separation of X and Y
chromosome-bearing spermatozoa using flow cytometry has been reported as a
clinical technique aiding prevention of X-linked diseases. Although this
technique has resulted in several hundred normal births in animals and at
least one human birth, there is still concern over its genetic safety due
to the involvement of two potentially mutagenic agents: UV light and the
fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly
those considered abnormal, may be more likely to suffer DNA damage
following exposure to mutagenic agents, compared with other mammalian
species. The stability of normal fresh and decondensed human spermatozoa
were examined after exposure to a range of levels of UV and H33342
staining, using an assay that detects endogenous nicks in the DNA of
spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed
human spermatozoa was examined following UV laser, H33342 staining and flow
cytometry treatments utilizing the same assay. There was an increase in the
presence of endogenous nicks when spermatozoa were decondensed compared
with fresh spermatozoa. There was no increase in the incidence of nicks in
any group of spermatozoa after UV and fluorochrome exposure compared with
controls without exposure.
相似文献
20.
P. Van de Perre N. Clumeck M. Steens G. Zissis M. Carapl R. Lagasse S. De Wit T. Lafontaine P. De Mol J. P. Butzler 《European journal of epidemiology》1987,3(1):14-18
A seroepidemiological study was performed on HTLV-III, T. pallidum, C. trachomatis and Hepatitis B virus (HBV), in Butare, Rwanda, among 33 female prostitutes, 25 male customers of prostitutes, and 60 male and female controls. As compared with female controls the prostitutes had a higher prevalence of antibodies to HTLV-III (29/33 versus 4/33, p<0.001), T. pallidunz (TPHA: 27/33 versus 6/33, p<0.001; RPR: 19/33 versus 233, p<0.001; FTA-Abs: 27/33 versus 5/33, p<0:001) and C. trachomatis (IgG IF: 31/33 versus 13/33, p<0.001). HBV serological markers were more often detected in the prostitutes than in the female controls (31/33 versus 18/33, p<0.001) although HBs antigen carriage rate was similar in both groups. As compared with male controls, the male customers of prostitutes had more frequently detectable antibodies to HTLV-III (7/25 versus 2/27, p = 0.05), and a positive RPR (10/25 versus 1/27, p<0.01). Among the 118 individuals studied, odds ratios and trend analysis disclosed a significant association between HTLV-III seropositivity and a positive TPHA, RPR, FTA-Abs, Chlamvdia IgG IF test and serological markers to HBV. No association was found between HTLV-III seropositivity and IIBs Ag carriage. This study suggests that HTLV-III has to be considered as an infectious agent transmitted among promiscuous Central African heterosexuals by sexual contact and/or parenteral contact with unsterile needles used for STD treatments. 相似文献