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51.
Shaw MM Gürr WK Thackray AM Watts PA Littler E Field HJ 《Journal of virological methods》2002,102(1-2):93-102
Levels of bystander death occurring in herpes simplex virus type 1 (HSV-1)-infected mouse brain stems were studied, as well as the extent to which bystander death is influenced by guanosine nucleoside analogue treatment. Consecutive sections from brain stems of HSV-1-infected mice were stained alternately for (i) viral infection and (ii) cell death (TUNEL assay). Virus antigen was detectable in brain stems on day 3 of infection, while TUNEL staining was comparatively lower. An increase in the extent of TUNEL staining was observed on day 4 of infection. Despite this increase, however, the ratio of TUNEL-stained to infection marker-stained tissue still indicated that the amount of TUNEL staining remained lower than infection staining at this time point. On days 5 and 6 of infection, TUNEL staining continued to increase and the TUNEL/infection marker ratio switched on day 6 in favour of excess TUNEL staining, which was observed in and around the foci of infection, suggesting bystander death. The excess TUNEL staining on day 6 of infection was further increased on treatment with antivirals. The significance and implications of these results are discussed with respect to the nature and mechanism of action of the TUNEL assay, dynamics of primary HSV-1 infection, immunological influences and potential effects of antiviral treatment. The potential problems of the TUNEL assay are considered in the context of viral infection and the TUNEL assay, in combination with infection marker staining, may potentially provide a model system for quantitative analysis of true bystander death during HSV infection in vivo. 相似文献
52.
Hore J Ritchie R Watts S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1999,125(3):302-312
Accuracy in an overarm throw requires great precision in the timing of finger opening. We tested the hypothesis that finger
opening in an overarm throw is triggered by proprioceptive feedback from elbow extension or wrist flexion. The hypothesis
was tested in two ways: first, by unexpectedly perturbing elbow extension or slowing wrist flexion and determining whether
changes occurred in finger opening, and second, by measuring the latency from the start of these joint rotations to the start
of finger opening. Subjects threw balls fast and accurately from a sitting or standing position while joint rotations were
recorded with the search-coil technique. Elbow extension was unexpectedly blocked near the start of forward motion of the
hand by a rope attached to the wrist that passed through a catch mechanism located behind the subject. In spite of a slowing
or complete block of elbow extension, and in some cases a replacement of elbow extension by elbow flexion, finger opening
always occurred and at the same latency as for normal throws. Wrist flexion was slowed in seven of eight subjects when subjects
changed from throwing with a light ball (14 g, 70 mm diam.) to a heavy ball (210 g, 65 mm diam.). For the first throw with
the heavy ball, this slowing was neither fully anticipated by the subject nor compensated for by the changed proprioceptive
feedback associated with the slowing. Consequently, the timing of finger opening was unchanged and (to the surprise of the
thrower) the ball went high. Furthermore, in unperturbed throws with tennis balls, the latency from onset of wrist flexion
or elbow extension to onset of finger opening was too short for either to have triggered finger opening (across subjects means
were 4 ms for wrist flexion and 21 ms for elbow extension). In additional analysis, no relation was found between the time
of onset of earlier occurring rotations at the shoulder and the time of onset of finger opening. We concluded that, although
a role for all proprioceptive feedback in triggering finger opening cannot be disproved by these experiments, it can be ruled
out for feedback arising from elbow extension and wrist flexion, and it seems unlikely for feedback arising from events occurring
very early in the throw. The more likely possibility is that finger opening in an overarm throw is triggered by a central
command based on an internal model of hand trajectory.
Received: 6 July 1998 / Accepted: 16 October 1998 相似文献
53.
APOE is a potential modifier gene in an autosomal dominant form of frontotemporal dementia (IBMPFD).
Sarju G Mehta Giles D J Watts Jennifer L Adamson Mike Hutton Geanie Umberger Shuling Xiong Sheena Ramdeen Mark A Lovell Virginia E Kimonis Charles D Smith 《Genetics in medicine》2007,9(1):9-13
PURPOSE: Inclusion-body myopathy, Paget's disease of bone and frontotemporal dementia is an adult-onset autosomal dominant illness (IBMPFD) caused by mutations in the valosin-containing protein (VCP) on chromosome 9p21.1-p12. The penetrance of the gene is 82% for myopathy, 49% for Paget's disease, but may be as low as 30% for frontotemporal dementia. Modifier genes could account for decreased frontotemporal dementia penetrance. In this study apolipoprotein-E (APOE) was evaluated for this role in IBMPFD families based on its known modifier effect in Alzheimer's disease. METHODS: From a database of 231 members of 15 families, 174 had APOE genotype available for analysis. Logistic regressions on APOE genotype and frontotemporal dementia were performed, using appropriate covariates. RESULTS AND CONCLUSION: FTD was associated with APOE 4 genotype (P=0.0002), myopathy (P=0.0006), and age (P=0.01), but not microtubule associated protein tau (MAPT) H2 haplotype (P=0.5) or gender (0.09) after adjustment for membership in pedigrees with at least one APOE 4 genotype. These data suggest a potential link between APOE 4 genotype and the specific form of frontotemporal dementia found in IBMPFD. The molecular basis of this link bears further investigation. We did not observe an association of frontotemporal dementia and H2 MAPT haplotype. 相似文献
54.
Summary The venous architecture in donor flaps was observed in 17 fresh cadavers by injection of latex or ink into the vessels or by making corrosion-cast specimens. The pattern of the veins resembles that of the arteries, with the difference that there is another set of venous trunks which do not accompany the arteries. Because these trunks are of larger caliber, they are the main drainage route for flaps. There are three types of drainage based on the anatomical architecture: 1) the superficial trunk is the main drainage path; 2) the deep trunk is the main path; 3) both superficial and deep veins are involved. These morphological considerations are the basis for selection of veins for anastomosis in microsurgery. The axial veins in temporal, frontal and facial flaps on the dorsum of the hand and the foot usually loosely accompany the axial arteries. The characteristics of these vascular pedicules should be studied in transplant operation.
Bases anatomiques du drainage veineux des lambeaux cutanés libres
Résumé Le drainage veineux des lambeaux cutanés libres a été étudié sur 17 cadavres frais par injection de latex ou d'encre dans les vaisseaux, ou en réalisant des moulages par injection-corrosion. La distribution des veines ressemble à celle des artères à la différence près qu'il existe des troncs veineux qui n'accompagnent pas les artères. Ces troncs ont un calibre plus important et représentent une voie de drainage principale pour les lambeaux. On peut individualiser trois types de drainages basés sur l'architecture veineuse : 1. Le tronc superficiel est la principale voie de drainage ; 2. le tronc profond est la principale voie; 3. les veines superficielles et profondes sont impliquées simultanément. Ces considérations morphologiques sont les bases de la sélection des axes veineux pour les anastomoses en micro-chirurgie. Les veines axiales au niveau temporal, frontal et facial et pour les lambeaux de la face dorsale de la main et du pied sont habituellement relativement éloignées du trajet artériel. Les caractéristiques de ces pédicules veineux doivent être précisées pour la réalisation des lambeaux.相似文献
55.
Acidosis and blood epinephrine levels in hemorrhagic hypotension 总被引:1,自引:0,他引:1
56.
Berhane K Karim R Cohen MH Masri-Lavine L Young M Anastos K Augenbraun M Watts DH Levine AM 《Journal of acquired immune deficiency syndromes (1999)》2004,37(2):1245-1252
BACKGROUND: Anemia is common in HIV-infected individuals and may be associated with decreased survival. OBJECTIVE: To ascertain the impact of highly active antiretroviral therapy (HAART) on anemia and the relationship between anemia and overall survival in HIV-infected women. METHODS: A prospective multicenter study of HIV-1 infection in women. Visits occurred every 6 months, including a standardized history, physical examination, and comprehensive laboratory evaluation. The setting was a university-affiliated clinic at 6 sites in the United States. Participants were 2056 HIV-infected women from the Women's Interagency HIV Study (WIHS). The outcome measure was anemia, defined as hemoglobin (Hb) <12 g/dL. Survival analysis was based on overall mortality during the follow-up period. RESULTS: Among HIV-infected women who were not anemic at baseline, 47% became anemic by 3.5 years of follow-up. On multivariate analysis, the use of HAART was associated with resolution of anemia even when used for only 6 months (odds ratio [OR] = 1.45; P < 0.05). In the multivariate model, a CD4 cell count <200 cells/microL (OR = 0.56; P < 0.001); HIV-1 RNA level > or =50,000 copies/mL (OR = 0.65; P < 0.001), and mean corpuscular volume (MCV) value <80 fL (OR = 0.40; P < 0.001) were also associated with an inability to correct anemia. Similarly, use of HAART for 12 months or more was associated with a protective effect against development of anemia (OR = 0.71; P < 0.001). Among HIV-infected women, anemia was independently associated with decreased survival (hazard ratio [HR] = 2.58; P < 0.001). Other factors associated with decreased survival included a CD4 cell count <200 cells/microL (HR = 5.83; P < 0.001), HIV-1 RNA level > or = 50,000 copies/mL (HR = 2.12; P < 0.001), and clinical diagnosis of AIDS (HR = 2.83; P < 0.001). CONCLUSIONS: Anemia is an independent risk factor for decreased survival among HIV-infected women. HAART therapy for as little as 6 months is associated with resolution of anemia. 相似文献
57.
Members of both the CD28 and TNFR families can have costimulatory roles in T cell activation. Gene targeted mice as well as in vivo blocking experiments have established distinct roles for CD28/B7; ICOS/ICOSL; CD27/CD70; 4-1BB/4-1BBL and OX40/OX40L during viral infection. Many issues remain to be addressed, including the timing and location of the interactions, the possibility of partial redundancy between related family members and the molecular basis for the specific phenotypes observed in the different gene targeted mice. 相似文献
58.
Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction 总被引:11,自引:16,他引:11
Silber SJ; Alagappan R; Brown LG; Page DC 《Human reproduction (Oxford, England)》1998,13(12):3332-3337
Y chromosome deletions encompassing the AZFc region have been reported in
13% of azoospermic men and 7% of severely oligozoospermic men. We examined
the impact of these Y deletions on the severity of testicular defects in 51
azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after
testicular sperm extraction (TESE) and 30 men with severe oligozoospermia
undergoing ICSI after ejaculation of spermatozoa. In addition, five
azoospermic patients shown previously to have Y chromosome deletions
underwent histological evaluation of their previously obtained testis
biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not
Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent
TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y
chromosome AZFc region. Of these 10, five had spermatozoa retrievable from
the testis, and in two cases the wives became pregnant. Of the 41
azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa
retrievable from the testis, and in 12 cases (29%) the wives became
pregnant. Four of 30 (13%) severely oligozoospermic patients were found to
be deleted for AZFc and in three (75%) of these pregnancy was achieved. The
other 26 severely oligozoospermic couples who had no AZFc deletions
underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The
embryo implantation rate was not significantly different for azoospermic
(22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the
total of 19 infertile men who had Y chromosome deletions, 14 had deletions
within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14
had some spermatozoa (however few in number) in the ejaculate or testis.
Five of the Y-deleted men had deletions that extended more proximally on
the Y chromosome, and in none of these could any spermatozoa be observed in
either ejaculate or testis. These results support the concept that, in
azoospermic or oligozoospermic men with Y chromosome deletions limited to
intervals 6D-6F (AZFc), there are generally very small numbers of
testicular or ejaculated spermatozoa. Larger Y deletions, including and
extending beyond the AZFc region and encompassing more Y genes, tend to be
associated with a total absence of testicular spermatozoa. In those cases
where spermatozoa were retrieved, the presence of Y deletions had no
obvious impact on fertilization or pregnancy rate.
相似文献
59.
60.
Christopher C. Norbury Benedict J. Chambers Alan R. Prescott Hans-Gustaf Ljunggren Colin Watts 《European journal of immunology》1997,27(1):280-288
Dendritic cells expanded from mouse bone marrow (BMDC) with granulocyte/macrophage-colony-stimulating factor have potent T cell-stimulatory properties both in vitro and in vivo. This has been well documented for major histocompatibility complex (MHC) class II-restricted responses, and more recently using peptide-loaded and protein-pulsed DC for CD8 responses following adoptive transfer in mice. An unresolved question concerns the capacity of BMDC to present exogenous antigen on MHC class I molecules, an unconventional mode of MHC class I loading for which there is now considerable evidence, particularly in macrophages. Here, we show that BMDC exhibit high levels of macropinocytosis driven by constitutive membrane ruffling activity. Up to one-third of actively ruffling and macropinocytosing BMDC transferred pinocytosed horseradish peroxidase into the cytosol following a 15-min pulse, suggesting that they might be capable of presenting exogenous soluble antigen on MHC class I molecules. We show that BMDC presented exogenous ovalbumin to a T cell hybridoma more effectively, more rapidly, and at lower exogenous antigen concentrations than BM macrophages on a cell-for-cell basis. Presentation was TAP dependent, brefeldin A sensitive, and blocked by inhibitors of proteasomal processing, demonstrating use of the classical MHC class I pathway. Although effective presentation of exogenous antigen by BMDC occurred in the absence of agents which stimulate macropinocytosis, treatment with phorbol myristate acetate (PMA) enhanced both pinocytosis and MHC class I presentation by BMDC. Finally, PMA-stimulated BMDC exposed to exogenous ovalbumin in vitro were able to prime an antigen-specific cytotoxic T lymphocyte response following adoptive transfer in vivo. 相似文献