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61.
Whether or not mechanisms underlying circadian locomotor rhythms and learning are related anatomically through the mushroom bodies (MBs) was investigated by monitoring behavioral rhythmicity in flies with MB lesions induced by chemical ablation and by mutations in five different genes. All flies tested were later examined histologically to assess (1) MB neuroanatomy, and (2) the condition of the putative pacemaker cells -- the ventral Lateral Neurons (LN v s) and their terminals that project to the vicinity of the MB calyces. All groups of flies had normal rhythms except for mushroom body miniature ( mbm ; only in a wild-type Berlin genetic background) and mushroom body defect ( mud ). MB ablation had no effect on the gender-specific differences in the rhythmic activity profile that are typical of wild-type flies. However, ablated males had a slightly longer period than untreated males and were more active under constant dark conditions. LN v s and their arborization patterns appeared normal in MB-ablated and in most mutant flies. Activity defects of mbm flies were attributed to genetic background rather than to the mutation alone. Misrouted LN v projections and ~14% arrhythmia of mud flies were uncorrelated and attributed to pleiotropy rather than to specific effects of MB lesions. Our results imply that MBs are not involved in circadian activity rhythms but that they do have an inhibitory effect on activity levels of male flies. 相似文献
62.
Camille Cenni Stephanie Andres Maja Hempel Tim M. Strom Ellen Thomas Angela Davies Norma Timoney Alessandra Frigiola Malcolm Logan Muriel Holder-Espinasse 《European journal of medical genetics》2021,64(7):104213
Holt-Oram syndrome (HOS) is a rare, autosomal dominant heart-hand syndrome caused by mutations in the TBX5 gene. A wide spectrum of TBX5 mutations have been reported previously, most resulting in a null allele leading to haploinsufficiency. TBX5 gene duplications have been previously reported in association with typical and atypical HOS phenotypes. Ulnar-Mammary syndrome (UMS) is a distinct rare, autosomal dominant condition caused by mutations in the TBX3 gene. TBX5 and TBX3 are physically linked in cis on human chromosome 12 and contiguous chromosome 12q24 deletions comprising both TBX5 and TBX3 genes have been previously reported but to our knowledge, duplications have never been described. We report on a large German family with at least 17 affected individuals over 6 generations bearing a duplication at 12q24.21 identified on array-CGH comprising both TBX5 and TBX3 genes. Affected patients are presenting with HOS and UMS symptoms, consisting of variable limb anomalies involving the radial and the ulnar rays and cardiac findings such as congenital heart defects, persistent arterial duct or aortic stenosis, and non-classical symptoms, such as supernumerary nipples and cardiomyopathy. Fluorescence in situ hybridisation confirmed a tandem duplication at the 12q24.21 locus. This is the first report of a contiguous TBX3/TBX5 duplication associated with HOS/UMS phenotype. 相似文献
63.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献
64.
Influence of Smoking Dosage and Chronic Obstructive Lung Disease on the Incidence of Appropriate Therapies and Mortality in Patients with Structural Heart Disease and an Implantable Cardioverter Defibrillator
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65.
Jessika A. Contreras Richard B. Wilder Eric A. Mellon Tobin J. Strom Daniel C. Fernandez Matthew C. Biagioli 《International braz j urol : official journal of the Brazilian Society of Urology》2015,41(1):40-45
Purpose
There is little information in the literature on health-related quality of life (HRQOL) changes due to high-dose-rate (HDR) brachytherapy monotherapy for prostate cancer.Materials and Methods
We conducted a prospective study of HRQOL changes due to HDR brachytherapy monotherapy for low risk or favorable intermediate risk prostate cancer. Sixty-four of 84 (76%) patients who were treated between February 2011 and April 2013 completed 50 questions comprising the Expanded Prostate Cancer Index Composite (EPIC) before treatment and 6 and/or 12 months after treatment.Results
Six months after treatment, there was a significant decrease (p<0.05) in EPIC urinary, bowel, and sexual scores, including urinary overall, urinary function, urinary bother, urinary irritative, bowel overall, bowel bother, sexual overall, and sexual bother scores. By one year after treatment, EPIC urinary, bowel, and sexual scores had increased and only the bowel overall and bowel bother scores remained significantly below baseline values.Conclusions
HDR brachytherapy monotherapy is well-tolerated in patients with low and favorable intermediate risk prostate cancer. EPIC urinary and sexual domain scores returned to close to baseline 12 months after HDR brachytherapy. 相似文献66.
67.
J S Meisner G Keren O E Pajaro A Mani J A Strom R W Frater S Laniado E L Yellin 《Circulation》1991,84(4):1469-1480
BACKGROUND. The importance of the contribution of atrial systole to ventricular filling in mitral stenosis is controversial. The cause of reduced cardiac output following the onset of atrial fibrillation may be due to an increased heart rate, a loss of booster pump function, or both. METHODS AND RESULTS. We studied the atrial contribution to filling under a variety of conditions by combining noninvasive studies of patients with computer modeling. Thirty patients in sinus rhythm with mild-to-severe stenosis were studied with two-dimensional and Doppler echocardiography for measurement of mitral flow velocity and mitral valve area (MVA). The mean +/- SD atrial contribution to left ventricular filling volume was 18 +/- 10% and varied inversely with mitral resistance. Patients with mild mitral stenosis (MVA, 1.8 +/- 0.7 cm2) and severe mitral stenosis (MVA, 0.9 +/- 0.2 cm2) had atrial contributions of 29 +/- 4% and 9 +/- 5%, respectively. The pathophysiological mechanisms responsible for these trends were further investigated by the computer model. In modeled severe mitral stenosis, increasing heart rate from 75 to 150 beats/min caused an increase of 5.2 mm Hg in mean left atrial pressure, whereas loss of atrial contraction at a heart rate of 150 beats/min caused only a 1.3 mm Hg increase. CONCLUSIONS. The atrial booster pump contributes less to ventricular filling in mitral stenosis than in the normal heart, and the loss of atrial pump function is less important than the effect of increasing heart rate as the cause of decompensation during atrial fibrillation. 相似文献
68.
Ingberg E Theodorsson A Theodorsson E Strom JO 《General and comparative endocrinology》2012,175(1):188-193
Rodent models constitute a cornerstone in the elucidation of the effects and biological mechanisms of 17β-estradiol. However, a thorough assessment of the methods for long-term administration of 17β-estradiol to mice is lacking. The fact that 17β-estradiol has been demonstrated to exert different effects depending on dose emphasizes the need for validated administration regimens. Therefore, 169 female C57BL/6 mice were ovariectomized and administered 17β-estradiol using one of the two commonly used subcutaneous methods; slow-release pellets (0.18 mg, 60-day release pellets; 0.72 mg, 90-day release pellets) and silastic capsules (with/without convalescence period, silastic laboratory tubing, inner/outer diameter: 1.575/3.175 mm, filled with a 14 mm column of 36 μg 17β-estradiol/mL sesame oil), or a novel peroral method (56 μg 17β-estradiol/day/kg body weight in the hazelnut cream Nutella). Forty animals were used as ovariectomized and intact controls. Serum samples were obtained weekly for five weeks and 17β-estradiol concentrations were measured using radioimmunoassay. The peroral method resulted in steady concentrations within--except on one occasion--the physiological range and the silastic capsules produced predominantly physiological concentrations, although exceeding the range by maximum a factor three during the first three weeks. The 0.18 mg pellet yielded initial concentrations an order of magnitude higher than the physiological range, which then decreased drastically, and the 0.72 mg pellet produced between 18 and 40 times higher concentrations than the physiological range during the entire experiment. The peroral method and silastic capsules described in this article constitute reliable modes of administration of 17β-estradiol, superior to the widely used commercial pellets. 相似文献
69.
L Tingey M Cwik N Goklish M Alchesay A Lee R Strom R Suttle J Walkup A Barlow 《The American journal of drug and alcohol abuse》2012,38(5):409-415
Background: Risk factors for binge substance use and non-suicidal self-injury (NSSI) are similar, suggesting the importance of exploring how binge substance use and self-injury interrelate. Objectives: To gain insight from a sample of American Indian (AI) adolescents regarding how binge drinking and drug use function in their lives, including as overlapping forms of self-injury, and to identify community-based ideas for dual prevention strategies. Methods: A total of N?=?58 White Mountain Apache (Apache) adolescents participated in ten mixed gender (n?=?33 males, 55.9%) focus group discussions. Results were interpreted and categorized by Apache researchers and compared to Nock's behavioral model of NSSI. Results: Participants reported substance use most commonly with "family" and "friends," "at a house," or "around the community." Substance use was not confined to a particular time of day, and often occurred "at school." Commonly endorsed reasons fell into two main categories: "to avoid problems" or "to reduce negative feelings," versus "to be cool" or "to feel part of a group." All adolescents but one thought that some youths use substances excessively as a way to harm/injure themselves (n?=?25 responses). Prevention approaches included encouraging healthy relationships, teaching about consequences of use, providing alternative recreation, and changing/enforcing laws on the reservation. Conclusion: Tribal-specific data support the idea that binge substance use sometimes functions as a form of self-injury. Home/school environments are critical prevention settings, in addition to improved law enforcement and increased recreation. Scientific Significance: Understanding possible shared root causes and functions of binge substance use and self-injury may advance integrated prevention approaches. 相似文献
70.