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61.
62.
Sharon Stansfield Carole Dennis Rachel Altman Janelle Smith Hélène Larin 《Assistive technology : the official journal of RESNA》2018,30(2):84-90
The onset of crawling in infants contributes to cognitive, perceptual, social, and emotional development. Conversely, infants with motor impairment that delays or prevents autonomous mobility often have associated developmental delays. Evidence suggests that providing mobility may have positive developmental outcomes, however powered wheelchairs may not be recommended for very young children, due to safety concerns and the child’s level of cognitive maturity. The WeeBot is a mobility device controlled by infant weight shifting while seated; infants as young as 5 months have learned to use it. This study compares the efficacy of using the WeeBot vs. using the traditional manual joystick to control a robotic mobility device. Participants were 20 typically developing infants between 5 and 10 months who had not yet achieved independent mobility. A quasi-experimental two-group design was used: The first 10 participants recruited used the WeeBot (weight-shift); the next 10 used the joystick. Results showed that infants learned to use weight-shift control more easily and more skilfully than did infants using the joystick. The ability of infants to use the WeeBot suggests that an intuitive alternative control might allow very early powered mobility for children with disabilities, which might have implications for various aspects of their development. 相似文献
63.
Scott Kizy Ariella M. Altman Schelomo Marmor Jason W. Denbo Eric H. Jensen Todd M. Tuttle Jane Yuet Ching Hui 《Journal of Geriatric Oncology》2019,10(2):322-329
Introduction
The 21-gene recurrence score (RS) (Oncotype Dx, Genomic Health, Redwood City Ca) has not been validated in an older cohort with estrogen receptor (ER)-positive breast cancer. The objective of this study was to evaluate RS validity in a group of older women with ER-positive breast cancer.Methods
Utilizing the Surveillance, Epidemiology, and End Results Program (SEER) database with available RS, we evaluated women with ER-positive breast cancer aged 18–69 and those 70?years of age and older from 2004 to 2014. We utilized multivariable logistic regression models to evaluate factors associated with RS testing as well as a high-risk categorization for those who underwent testing. Survival was analyzed using Kaplan Meier curves and Cox proportional hazard models.Results
We identified 363,876 women aged 18–69?years and 147,107 women aged 70?years and older. A smaller proportion of patients in the older group (8%) underwent RS testing than in the younger group (18%). Of the patients who underwent testing, distribution of RS was similar between groups. High-risk categorization independently predicted a higher likelihood of death for older patients (hazard ratio 1.47, 95% confidence interval 1.15–1.90). Among patients with high-risk RS, chemotherapy was associated with a decreased risk of death in the younger group, but not in the older group.Conclusion
Older women are less likely to receive RS testing, but when tested, older patients have a similar distribution of RS as compared to younger patients. While high-risk categorization in the older cohort was prognostic, chemotherapy was not associated with improved survival. 相似文献64.
65.
66.
Andrea Haller Roger B. Altman Marie F. Soulière Scott C. Blanchard Ronald Micura 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(11):4188-4193
Thiamine pyrophosphate (TPP)-sensitive mRNA domains are the most prevalent riboswitches known. Despite intensive investigation, the complex ligand recognition and concomitant folding processes in the TPP riboswitch that culminate in the regulation of gene expression remain elusive. Here, we used single-molecule fluorescence resonance energy transfer imaging to probe the folding landscape of the TPP aptamer domain in the absence and presence of magnesium and TPP. To do so, distinct labeling patterns were used to sense the dynamics of the switch helix (P1) and the two sensor arms (P2/P3 and P4/P5) of the aptamer domain. The latter structural elements make interdomain tertiary contacts (L5/P3) that span a region immediately adjacent to the ligand-binding site. In each instance, conformational dynamics of the TPP riboswitch were influenced by ligand binding. The P1 switch helix, formed by the 5′ and 3′ ends of the aptamer domain, adopts a predominantly folded structure in the presence of Mg2+ alone. However, even at saturating concentrations of Mg2+ and TPP, the P1 helix, as well as distal regions surrounding the TPP-binding site, exhibit an unexpected degree of residual dynamics and disperse kinetic behaviors. Such plasticity results in a persistent exchange of the P3/P5 forearms between open and closed configurations that is likely to facilitate entry and exit of the TPP ligand. Correspondingly, we posit that such features of the TPP aptamer domain contribute directly to the mechanism of riboswitch-mediated translational regulation. 相似文献
67.
José Villar MD Leila Cheikh Ismail Prof Cesar G Victora Eric O Ohuma Prof Enrico Bertino Prof Doug G Altman Ann Lambert Aris T Papageorghiou Maria Carvalho Yasmin A Jaffer Michael G Gravett Manorama Purwar Ihunnaya O Frederick Prof Alison J Noble Prof Ruyan Pang Prof Fernando C Barros Prof Cameron Chumlea Prof Zulfiqar A Bhutta Stephen H Kennedy 《Lancet》2014
68.
Amnon Zung Yardena Tenenbaum‐Rakover Shiri Barkan Aaron Hanukoglu Eli Hershkovitz Orit Pinhas‐Hamiel Tzvy Bistritzer Zvi Zadik 《Clinical endocrinology》2010,72(2):264-271
Introduction Neonatal hyperthyrotropinaemia (HT), defined by elevated TSH and normal T4, is either transient or persistent. The eventual outcome of neonatal HT is unpredictable and the management of HT patients is controversial. We assessed perinatal parameters and diagnostic measures that may distinguish between transient and persistent HT, compared with congenital hypothyroidism (CH). We also aimed to recommend optimal treatment in these forms of thyroid impairment. Design and patients A multi‐centre, retrospective study was conducted in six paediatric endocrinology units. Forty‐three HT patients and 83 CH patients were included in the study. Measurements We evaluated differences in birth weight (BW), gestational age (GA), modes of diagnosis, screening and confirmatory T4 and TSH levels, thyroid imaging results and optimal thyroxine doses between HT and CH and between the two forms of HT. Results Newborns with HT had lower BW and GA than those with CH. Transient (n = 18) and persistent HT (n = 25) patients were indistinguishable by most parameters, but those with persistent HT had a higher prevalence of abnormal thyroid imaging (69%vs 8%; P = 0·005). During treatment, 79% and 55% of transient and persistent HT patients respectively experienced elevated levels of free T4. Although most HT patients were reevaluated after 2·5 years, six transient HT patients stopped therapy and showed full recovery within the first year of life. Conclusions We recommend obtaining thyroid imaging to distinguish between the two forms of HT. Adherence to recommended doses of thyroxine and probably early cessation of therapy in transient HT can prevent iatrogenic hyperthyroidism in these patients. 相似文献
69.
Middle-aged and older persons living with HIV/AIDS have unique needs arising from the physical, mental, and social changes associated not only with normal aging but also related to living with a chronic illness. To address these needs, two 10-week telephone psychoeducational support groups were offered for HIV-infected persons aged 50 or older. Each group was cofacilitated by a registered nurse and a social worker; each session was 50-60 minutes every Friday; approximately 1-5 clients participated with an average number of 3 clients and there was no charge to the participants. The issues addressed in the group were: (1) staying healthy; (2) symptom management; (3) understanding other chronic illnesses; (4) understanding diagnostic tests; (5) strategies for effective interactions with the health care provider; (6) optimizing HIV/AIDS medication use; (7) understanding new developments in HIV treatment; (8) coping with losses; and (9) finding commonalities. There were unique challenges. Boundaries of respect were more difficult to maintain in a teleconference, as opposed to an in-person group. Nonverbal cues were impossible to interpret and therefore greater sensitivity was required to gauge the impact of borderline, less controlled group members, especially in relationship to other group members who may tend to be less assertive. One group member withdrew because his hearing was impaired and the telephone modality was just too challenging. It has been found that middle-aged and older adults living with HIV/AIDS with greater depression identify a need for information and support. It is crucial to share concrete information, identify symptoms clearly, and explore the use of effective and ineffective medications and treatments. The psychosocial concerns are very real and encouraging group members to open up to one another to create a cohesive community of sharing is equally important. Although the use of teleconference technology makes this more difficult, the attempt to create a situation that facilitates connections with another individual is one strategy to decrease geographic or logistical isolation. 相似文献
70.
Zung A Glaser B Nimri R Zadik Z 《The Journal of clinical endocrinology and metabolism》2004,89(11):5504-5507
Permanent neonatal diabetes mellitus (PNDM) is a rare form of diabetes characterized by insulin-requiring hyperglycemia that is diagnosed within the first months of life. Recently, activating mutations in the gene encoding the ATP-sensitive potassium-channel subunit Kir6.2 were identified in 10 PNDM patients. Tolbutamide-stimulated insulin secretion, demonstrated in 3 of these patients suggested that some PNDM patients may respond to oral sulfonylurea treatment. In this report, we describe an infant with PNDM due to an arginine-to-histidine substitution at position 201 (R201H) of the gene encoding Kir6.2. After insulin pump therapy for six months, he was shifted to oral glybenclamide therapy at a daily dose of 0.8 mg/kg. Basal c-peptide level increased by two fold during glybenclamide treatment, but no further elevation was observed following intravenous glucose administration. Outpatient, continuous glucose monitoring while on a normal infant diet demonstrated a marked improvement in glycemic control. This study demonstrates the feasibility of oral sulfonylurea treatment in PNDM patients with Kir6.2 mutations even during infancy, and the superiority of this approach over insulin administration. 相似文献