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81.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
相似文献
82.
S J Bowne S P Daiger M M Hims M M Sohocki K A Malone A B McKie J R Heckenlively D G Birch C F Inglehearn S S Bhattacharya A Bird L S Sullivan 《Human molecular genetics》1999,8(11):2121-2128
Retinitis pigmentosa is a genetically heterogeneous form of retinal degeneration that affects approximately 1 in 3500 people worldwide. Recently we identified the gene responsible for the RP1 form of autosomal dominant retinitis pigmentosa (adRP) at 8q11-12 and found two different nonsense mutations in three families previously mapped to 8q. The RP1 gene is an unusually large protein, 2156 amino acids in length, but is comprised of four exons only. To determine the frequency and range of mutations in RP1 we screened probands from 56 large adRP families for mutations in the entire gene. After preliminary results indicated that mutations seem to cluster in a 442 nucleotide segment of exon 4, an additional 194 probands with adRP and 409 probands with other degenerative retinal diseases were tested for mutations in this region alone. We identified eight different disease-causing mutations in 17 of the 250 adRP probands tested. All of these mutations are either nonsense or frameshift mutations and lead to a severely truncated protein. Two of the eight different mutations, Arg677X and a 5 bp deletion of nucleotides 2280-2284, were reported previously, while the remaining six mutations are novel. We also identified two rare missense changes in two other families, one new polymorphic amino acid substitution, one silent substitution and a rare variant in the 5'-untranslated region that is not associated with disease. Based on this study, mutations in RP1 appear to cause at least 7% (17/250) of adRP. The 5 bp deletion of nucleotides 2280-2284 and the Arg677X nonsense mutation account for 59% (10/17) of these mutations. Further studies will determine whether missense changes in the RP1 gene are associated with disease, whether mutations in other regions of RP1 can cause forms of retinal disease other than adRP and whether the background variation in either the mutated or wild-type RP1 allele plays a role in the disease phenotype. 相似文献
83.
Alwan S Armstrong L Joe H Birch PH Szudek J Friedman JM 《American journal of medical genetics. Part A》2007,(12):1326-1333
The characteristic sites of Neurofibromatosis 1-associated osseous manifestations are the long bones (usually the tibia and fibula), vertebrae and sphenoid wing. Although these focal bony lesions may cause profound clinical consequences, a minority of people with NF1 are affected. However, most people with NF1 are shorter than expected for their age, gender and family. The pathogenesis of NF1 focal osteopathy and its relationship, if any, to short stature are unknown. We examined associations between the occurrence of various osseous lesions in 3377 NF1 probands from the Children's Tumor Foundation NF International Database. Using logistic regression analysis among 260 NF1 probands who had undergone radiological examination of both the spine and skull, we found associations between the occurrence of sphenoid wing and long bone osteopathy (conditional odds ratio [OR] = 6.1; 95% confidence interval [CI] = 1.7-22.3; P = 0.006) and between sphenoid wing and vertebral osteopathy (OR = 16.9; 95% CI = 5.3-53.3; P < 0.001) after adjusting for age and gender. Similar findings were observed from all 3377 NF1 probands using a multivariate probit regression model. In a separate analysis, we found lower age- and gender-standardized height in patients who had characteristic vertebral or sphenoid wing lesions than in people who did not (P < 0.05). We found no relationship between height and tibial osteopathy. We conclude that some people with NF1 are more likely to develop osseous manifestations than others and speculate that there may be a common pathogenetic mechanism responsible for the development of osseous abnormalities and that of the vertebrae and long bones. 相似文献
84.
Morse CI Thom JM Mian OS Birch KM Narici MV 《European journal of applied physiology》2007,100(5):563-570
The aim of the present investigation was to determine whether muscle force per physiological cross sectional area (PCSA) of
the lateral gastrocnemius (GL) of elderly males increased following a 12-month physical training programme. Eleven elderly
males were assigned to a 12-month training programme (TRN mean age 72.7 ± 3.3 years, mean ± SD) and eight elderly males were
allocated to a control group (CTRL, 73.9 ± 4.0 years) who maintained their habitual physical activity levels. In vivo measurements
of muscle architecture, muscle volume (VOL), achilles tendon moment arm length and plantarflexor torque were used to estimate
GL PCSA (VOL/fascicle length) and specific force (GL fascicle force/GL PCSA). Maximal GL fascicle force was calculated accounting
for agonist muscle activation and antagonist co-activation. Following training GL fascicle force increased by 31% (P < 0.01), which was not entirely accounted for by a 17% increase in PCSA (from 27.2 ± 5.9 to 31.8 ± 6.2 cm2, P < 0.05). Specific force increased significantly from 8.9 ± 1.9 to 11.2 ± 3.0 N cm−2 (P < 0.05). Pennation angle, but not fascicle length, increased by 12% with training (P < 0.05). The CTRL group showed no change in muscle size, strength or architecture over the 12-month period. In conclusion,
with the level of agonist and antagonist muscle activity accounted for a 12-month strength training programme resulted in
an increase in both PCSA and specific force in elderly males. 相似文献
85.
86.
Tara Donker Katherine Petrie Judy Proudfoot Janine Clarke Mary-Rose Birch Helen Christensen 《Journal of medical Internet research》2013,15(11)
Background
The rapid growth in the use of mobile phone applications (apps) provides the opportunity to increase access to evidence-based mental health care.Objective
Our goal was to systematically review the research evidence supporting the efficacy of mental health apps for mobile devices (such as smartphones and tablets) for all ages.Methods
A comprehensive literature search (2008-2013) in MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, PsycINFO, PsycTESTS, Compendex, and Inspec was conducted. We included trials that examined the effects of mental health apps (for depression, anxiety, substance use, sleep disturbances, suicidal behavior, self-harm, psychotic disorders, eating disorders, stress, and gambling) delivered on mobile devices with a pre- to posttest design or compared with a control group. The control group could consist of wait list, treatment-as-usual, or another recognized treatment.Results
In total, 5464 abstracts were identified. Of those, 8 papers describing 5 apps targeting depression, anxiety, and substance abuse met the inclusion criteria. Four apps provided support from a mental health professional. Results showed significant reductions in depression, stress, and substance use. Within-group and between-group intention-to-treat effect sizes ranged from 0.29-2.28 and 0.01-0.48 at posttest and follow-up, respectively.Conclusions
Mental health apps have the potential to be effective and may significantly improve treatment accessibility. However, the majority of apps that are currently available lack scientific evidence about their efficacy. The public needs to be educated on how to identify the few evidence-based mental health apps available in the public domain to date. Further rigorous research is required to develop and test evidence-based programs. Given the small number of studies and participants included in this review, the high risk of bias, and unknown efficacy of long-term follow-up, current findings should be interpreted with caution, pending replication. Two of the 5 evidence-based mental health apps are currently commercially available in app stores. 相似文献87.
Mark Rakobowchuk Emma Harris Annabelle Taylor Richard M. Cubbon Karen M. Birch 《European journal of applied physiology》2013,113(4):839-849
Traditional continuous aerobic exercise training attenuates age-related increases of arterial stiffness, however, training studies have not determined whether metabolic stress impacts these favourable effects. Twenty untrained healthy participants (n = 11 heavy metabolic stress interval training, n = 9 moderate metabolic stress interval training) completed 6 weeks of moderate or heavy intensity interval training matched for total work and exercise duration. Carotid artery stiffness, blood pressure contour analysis, and linear and non-linear heart rate variability were assessed before and following training. Overall, carotid arterial stiffness was reduced (p < 0.01), but metabolic stress-specific alterations were not apparent. There was a trend for increased absolute high-frequency (HF) power (p = 0.10) whereas both absolute low-frequency (LF) power (p = 0.05) and overall power (p = 0.02) were increased to a similar degree following both training programmes. Non-linear heart rate dynamics such as detrended fluctuation analysis $({| {1 - \alpha_{1} }|})$ also improved (p > 0.05). This study demonstrates the effectiveness of interval training at improving arterial stiffness and autonomic function, however, the metabolic stress was not a mediator of this effect. In addition, these changes were also independent of improvements in aerobic capacity, which were only induced by training that involved a high metabolic stress. 相似文献
88.
OBJECTIVE—To analyse the distributions of and generate growth charts for stature and occipitofrontal circumference (OFC) in neurofibromatosis 1 (NF1) patients.
DESIGN—Cross sectional database survey.
SETTING—The National Neurofibromatosis Foundation International Database (NFDB) includes clinical information on NF1 patients from 14 participating centres in North America.
SUBJECTS—A total of 569 white, North American, NF1 patients, 55% female and 45% male.
MAIN OUTCOME MEASURES—Stature and OFC measurements of NF1 patients were compared to age and sex matched population norms using z score standardisation and centile curves.
RESULTS—The distributions of stature and OFC are shifted and unimodal among NF1 patients; 13% of patients have short stature (2 standard deviations below the population mean) and 24% have macrocephaly (OFC 2 standard deviations above the population mean).
CONCLUSIONS—Alterations of stature and OFC are not limited to NF1 patients with frank short stature or macrocephaly.
Keywords: neurofibromatosis 1; stature; occipitofrontal circumference; macrocephaly 相似文献
DESIGN—Cross sectional database survey.
SETTING—The National Neurofibromatosis Foundation International Database (NFDB) includes clinical information on NF1 patients from 14 participating centres in North America.
SUBJECTS—A total of 569 white, North American, NF1 patients, 55% female and 45% male.
MAIN OUTCOME MEASURES—Stature and OFC measurements of NF1 patients were compared to age and sex matched population norms using z score standardisation and centile curves.
RESULTS—The distributions of stature and OFC are shifted and unimodal among NF1 patients; 13% of patients have short stature (2 standard deviations below the population mean) and 24% have macrocephaly (OFC 2 standard deviations above the population mean).
CONCLUSIONS—Alterations of stature and OFC are not limited to NF1 patients with frank short stature or macrocephaly.
Keywords: neurofibromatosis 1; stature; occipitofrontal circumference; macrocephaly 相似文献
89.
目的:探讨如达溃疡散对大鼠乙酸性胃溃疡的作用及对其血清促胃液素(gastrin)含量的影响.方法:采用乙酸法复制胃溃疡模型,将大鼠随机分为对照组、如达溃疡散组、雷尼替丁组,观察如达溃疡散对大鼠胃溃疡的作用,并检测其对大鼠血清中促胃液素含量的影响.结果:与对照组相比,如达溃疡散能明显抑制溃疡的发生,抑制血清促胃液素含量.结论:如达溃疡散具有抗胃溃疡的作用,其作用机理可能是通过抑制促胃液素释放,进一步减少胃酸分泌来实现的. 相似文献
90.