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1.

Objectives

The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.

Design

Pilot randomised-controlled trial.

Methods

Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.

Results

All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.

Conclusions

This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials.  相似文献   
2.
Summary: T cells and natural killer (NK) cells are presumed to share a common intrathymic precursor. The development of conventional a|3 T lymphocytes begins within the early fetal thymus, after the colonization of multipotent CDl1 71 precursors. Irrevocable commitment to the T lineage is marked by thymus-induced expression of CD25. However, the contribution of the fetal thymus to NK lineage commitment and differentiation remains largely unappreciated. Recently, we demonstrated that the development of functional mouse NK cells occurs first in the fetal thymus. Moreover, the appearance of mature fetal thymic NK cells (NK1.1+/CD 117-) is preceded by a thymus-induced developmental stage (NKl.1+/CD1 17+) that marks lineage commitment of multipotent hematopoietic precursors to the T and NK-cell fates. Commitment to the T/NK bipotent stage is induced by fetal thymic stroma, but is not thymus dependent. Recent data indicate that CD90+/CD117lo fetal blood prothymocytes exhibit NK lineage potential and are phenotypically and functionally identical to fetal thymic NK1,1+/CD1 17+ progenitors. This finding also indicates that full commitment of circulating precursors to the T-cell lineage occurs after thymus colonization. In this review, we discuss recent insights into the cellular and molecular events involved in fetal mouse T and NK lineage commitment and differentiation to unipotent progenitors.  相似文献   
3.
4.
Adolescent pregnancy is a social issue that severely jeopardizes the quality of life for young parents and their children. It is estimated that if fertility rates remain unchanged, the United States will see a 26% increase in the number of adolescent pregnancies and births due to an increase in the adolescent population (Henshaw, 1996). With a disproportional rate of Black adolescents becoming pregnant, there is a need to examine factors related to the high adolescent pregnancy rate among the Black community. Black adolescent mothers and their children face additional adverse psychosocial effects due to healthcare disparities, a higher incidence of health problems, and an increase risk of financial hardship (Hogan, Astone, & Kitagawa, 1985; J. V. Horn, 1998; Morgan, Chapar, & Fisher, 1995). Although the teenage pregnancy rate has declined, it is important for practitioners to continue to implement interventions that promote abstinence and increase contraceptive use among sexually active adolescents.  相似文献   
5.
The activin type II receptorgene (ACTRII) is mutated in 58.1% of microsatellite-unstable (MSI-H) colorectal cancers and is a close relative of the TGFbeta-1 type II receptor, which is known to be involved in both MSI-H and non-MSI-H colorectal carcinogenesis. We therefore sought to determine whether ACTRII was involved in non-MSI-H colorectal cancers. We evaluated ACTRII inactivation by allelic deletion, loss of mRNA expression, or somatic mutation in 51 non-MSI-H colon cancers. Loss of heterozygosity (LOH) at the ACTRII locus (2q23.1) was found in 9 (17.6%) of 51 primary tumors. Loss of ACTRII mRNA expression was seen in one (14.3%) of the seven LOH-positive primary tumors from which total RNA was available. We also performed DNA sequencing analysis of tumors showing LOH. One LOH-positive primary tumor exhibited a novel germline missense sequence alteration (amino acid substitution, 117 Ile to Phe) that was not found in 23 additional normal individuals, implying that this alteration is not a frequent polymorphism. We conclude that ACTRII is probably involved in both non-MSI-H and MSI-H colorectal carcinogenesis, but more frequently in the latter subgroup.  相似文献   
6.
The cannabinoid system and immune modulation   总被引:13,自引:0,他引:13  
  相似文献   
7.
BackgroundFindings regarding longer term symptoms of depression and the impact of depression on outcomes such as weight loss and patient satisfaction, are mixed or lacking.ObjectivesThis study sought to understand the relationship between depression, weight loss, and patient satisfaction in the two years after bariatric surgery.SettingThis study used data from a multi-institutional, statewide quality improvement collaborative of 45 different bariatric surgery sites.MethodsParticipants included patients (N = 1991) who underwent Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) between 2015–2018. Participants self-reported symptoms of depression (Patient Health Questionnaire-8 [PHQ-8]), satisfaction with surgery, and weight presurgery and 1 year and 2 years postsurgery.ResultsCompared to presurgery, fewer patients’ PHQ-8 scores indicated clinically significant depression (PHQ-8≥10) at 1 year (P < .001; 14.3% versus 5.1%) and 2 years postsurgery (P < .0001; 8.7%). There was a significant increase in the prevalence of clinical depression from the first to second year postsurgery (P < .0001; 5.1% versus 8.7%). Higher PHQ-8 at baseline was related to less weight loss (%Total Weight Loss [%TWL] and %Excess Weight Loss [%EWL]) at 1 year postsurgery (P < .001), with a trend toward statistical significance at 2 years (P = .06). Postoperative depression was related to lower %TWL and %EWL, and less reduction in body mass index (BMI) at 1 year (P < .001) and 2 years (P < .0001). Baseline and postoperative depression were associated with lower patient satisfaction at both postoperative time points.ConclusionsThis study suggests improvements in depression up to 2 years postbariatric surgery, although it appears that the prevalence of depression increases after the first year. Depression, both pre- and postbariatric surgery, may impact weight loss and patient satisfaction.  相似文献   
8.
PURPOSE: To assess the antitumor efficacy of pharmacokinetically guided topotecan dosing in previously untreated patients with medulloblastoma and supratentorial primitive neuroectodermal tumors, and to evaluate plasma and CSF disposition of topotecan in these patients. PATIENTS AND METHODS: After maximal surgical resection, 44 children with previously untreated high-risk medulloblastoma were enrolled, of which 36 were assessable for response. The topotecan window consisted of two cycles, administered initially as a 30-minute infusion daily for 5 days, lasting 6 weeks. Pharmacokinetic studies were conducted on day 1 to attain a topotecan lactone area under the plasma concentration-time curve (AUC) of 120 to 160 ng/mL.h. After 10 patients were enrolled, the infusion was modified to 4 hours, with dosage individualization. RESULTS: Of 36 assessable patients, four patients (11.1%) had a complete response and six (16.6%) showed a partial response, and disease was stable in 17 patients (47.2%). Toxicity was mostly hematologic, with only one patient experiencing treatment delay. The target plasma AUC was achieved in 24 of 32 studies (75%) in the 30-minute infusion group, and in 58 of 93 studies (62%) in the 4-hour infusion group. The desired CSF topotecan exposure was achieved in seven of eight pharmacokinetic studies when the topotecan plasma AUC was within target range. CONCLUSION: Topotecan is an effective agent against pediatric medulloblastoma in patients who have received no therapy other than surgery. Pharmacokinetically guided dosing achieved the target plasma AUC in the majority of patients. This drug warrants testing as part of standard postradiation chemotherapeutic regimens. Furthermore, these results emphasize the importance of translational research in drug development, which in this case identified an effective drug.  相似文献   
9.

Background  

Our goal was to quantify the evidence that is available to the physicians of a pediatric emergency department (PED) in making treatment decisions. Further, we wished to ascertain what percentage of evidence for treatment provided in the PED comes from pediatric studies.  相似文献   
10.
Study of an outbreak of ciguatera fish poisoning in Hong Kong.   总被引:5,自引:0,他引:5  
Ciguatera fish poisoning (CFP) has been a significant and increasing public health problem in Hong Kong since 1980s. With growing demand for imported live coral fishes, the number of people who suffered from this disease has also been increasing. An outbreak of CFP in 2004 was the second most prominent in record as compared with the most significant one that occurred in 1998. In 2004, out of a total of 823 reported food poisoning outbreaks involving 3159 persons, 65 incidents (7.9%) affecting 247 people (7.8%) were attributed to CFP. Validated mouse bioassay analysis of surveillance samples revealed that seven samples (13%) were confirmed to be contaminated with ciguatoxins (CTXs). Typical symptoms of CTXs were found in mice injected with 20mg of fish extracts. The causative fishes included Cheilinus undulatus, Epinephelus coioides, Plectropomus areolatus, and Plectropomus leopardus. Most of these CTX-positive samples analyzed had only trace amounts of CTXs in their extract, except a C. undulatus sample which contained a mice lethal dose (2.5MU/20mg ether extract). This fish species was also the major origin of coral fish that caused clusters of CFP in the last quarter of 2004. Cigua-Check analysis of 20 flesh grains from seven CTX-positive fishes, previously confirmed as CTX-positive samples by mouse bioassay, showed that 50% of flesh grains were CTX contaminated.  相似文献   
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