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81.
Richard Ro Dan Halpern David J. Sahn Peter Homel Milla Arabadjian Charles Lopresto Mark V. Sherrid 《Journal of the American College of Cardiology》2014
Background
The hydrodynamic cause of systolic anterior motion of the mitral valve (SAM) is unresolved.Objectives
This study hypothesized that echocardiographic vector flow mapping, a new echocardiographic technique, would provide insights into the cause of early SAM in obstructive hypertrophic cardiomyopathy (HCM).Methods
We analyzed the spatial relationship of left ventricular (LV) flow and the mitral valve leaflets (MVL) on 3-chamber vector flow mapping frames, and performed mitral valve measurements on 2-dimensional frames in patients with obstructive and nonobstructive HCM and in normal patients.Results
We compared 82 patients (22 obstructive HCM, 23 nonobstructive HCM, and 37 normal) by measuring 164 LV pre- and post-SAM velocity vector flow maps, 82 maximum isovolumic vortices, and 328 2-dimensional frames. We observed color flow and velocity vector flow posterior to the MVL impacting them in the early systolic frames of 95% of obstructive HCM, 22% of nonobstructive HCM, and 11% of normal patients (p < 0.001). In both pre- and post-SAM frames, we measured a high angle of attack >60° of local vector flow onto the posterior surface of the leaflets whether the flow was ejection (59%) or the early systolic isovolumic vortex (41%). Ricochet of vector flow, rebounding off the leaflet into the cul-de-sac, was noted in 82% of the obstructed HCM, 9% of nonobstructive HCM, and none (0%) of the control patients (p < 0.001). Flow velocities in the LV outflow tract on the pre-SAM frame 1 and 2 mm from the tip of the anterior leaflet were low: 39 and 43 cm/s, respectively.Conclusions
Early systolic flow impacts the posterior surfaces of protruding MVL initiating SAM in obstructive HCM. 相似文献82.
83.
Fiene Marie Kuijper Uma V. Mahajan Seul Ku Daniel A.N. Barbosa Sheila M. Alessi Sherman C. Stein Kyle M. Kampman Brandon S. Bentzley Casey H. Halpern 《Neuromodulation》2022,25(2):253-262
ObjectivesCocaine is the second most frequently used illicit drug worldwide (after cannabis), and cocaine use disorder (CUD)-related deaths increased globally by 80% from 1990 to 2013. There is yet to be a regulatory-approved treatment. Emerging preclinical evidence indicates that deep brain stimulation (DBS) of the nucleus accumbens may be a therapeutic option. Prior to expanding the costly investigation of DBS for treatment of CUD, it is important to ensure societal cost-effectiveness.AimsWe conducted a threshold and cost-effectiveness analysis to determine the success rate at which DBS would be equivalent to contingency management (CM), recently identified as the most efficacious therapy for treatments of CUDs.Materials and MethodsQuality of life, efficacy, and safety parameters for CM were obtained from previous literature. Costs were calculated from a societal perspective. Our model predicted the utility benefit based on quality-adjusted life-years (QALYs) and incremental-cost-effectiveness ratio resulting from two treatments on a one-, two-, and five-year timeline.ResultsOn a one-year timeline, DBS would need to impart a success rate (ie, cocaine free) of 70% for it to yield the same utility benefit (0.492 QALYs per year) as CM. At no success rate would DBS be more cost-effective (incremental-cost-effectiveness ratio <$50,000) than CM during the first year. Nevertheless, as DBS costs are front loaded, DBS would need to achieve success rates of 74% and 51% for its cost-effectiveness to exceed that of CM over a two- and five-year period, respectively.ConclusionsWe find DBS would not be cost-effective in the short term (one year) but may be cost-effective in longer timelines. Since DBS holds promise to potentially be a cost-effective treatment for CUDs, future randomized controlled trials should be performed to assess its efficacy. 相似文献
84.
Diamond-Blackfan syndrome: evidence against cell-mediated erythropoietic suppression 总被引:2,自引:1,他引:2
The profound anemia of Diamond-Blackfan syndrome (DBS) is due to marrow red cell failure, but the pathogenesis is not understood. Studies by others indicated cell-mediated erythropoietic suppression in this condition. To explore this mechanism further, Ficoll-Hypaque--separated peripheral blood lymphocytes (PBL) from four anemic untreated patients with DBS, or from normals were cocultured with control marrow in vitro and the growth of erythropoietin-responsive stem cell colonies (CFU-E) was dermined. CFU-E numbers obtained from cultures with added normal PBL were not significantly different from the number without PBL. Similarly, CFU-E from cultures with added DBS PBL were not significantly different from the number without PBL (215 versus 220, 229 versus 220 and 84 versus 60, 74 versus 94/10(5) cells, respectively). Mixing marrows from a control and one DBS patient in ratios of 2:1, 1:1, or 1:2 prior to culture failed to disclose a decrease of colony growth. We could not show cellular inhibition of erythropoiesis in these patients with DBS. The mechanism of anemia in this disorder remains an open question. 相似文献
85.
J Przybylski P A Chiale M S Halpern J O Lzzari M V Elizari M B Rosenbaum 《Heart (British Cardiac Society)》1978,40(6):672-680
Escape beats probably arising from the anomalous bundle were documented in 2 patients with the Wolff-Parkinson-White (WPW) syndrome. A third patient, in whom complete AV block developed both in the anomalous bundle and the normal pathway, showed the occurrence of escape beats (an escape-bigeminy pattern), as well as a regular idioventricular rhythm arising from the anomalous bundle. Phase 4 block in the anomalous bundle occurred in 7 other patients, in 4 of them spontaneously and in 3 only after the administration of ajmaline or amiodarone. Only 4 of 14 fully investigated patients (out of a total number of 23) showed absence of both escape beats and phase 4 block. The escape beats were considered as direct evidence, and the phase 4 block as indirect evidence, for the existence of automaticity in the anomalous bundle. Such evidence supports the view that the anomalous bundle, like the His bundle-branch system, may be composed of specialised tissue endowed with the property of automaticity. 相似文献
86.
OBJECTIVE: To examine the moderating effects of child-rearing attitudes on the relation between parenting stress and infant behavioral characteristics for mothers of very-low-birth-weight (VLBW) and full-term infants. METHODS: Fifty-six 9-month-old infants (23 VLBW and 33 full-term) and their mothers were the participants. Mothers completed measures of parenting stress, child-rearing attitudes, infant temperament, and infant behavioral problems. RESULTS: The VLBW infants had a higher frequency of behavioral problems, and their mothers reported more child health concerns than the mothers of the full-term infants. Regression analyses showed that the relation between parenting stress and infant distress was moderated at medium and high levels of parental strictness for only the VLBW infants. CONCLUSIONS: The amount of stress the mothers of the VLBW infants experienced was a result of the congruence between their infant's behavioral characteristics and their own child-rearing attitudes. 相似文献
87.
Basel-Vanagaite L Taub E Halpern GJ Drasinover V Magal N Davidov B Zlotogora J Shohat M 《European journal of human genetics : EJHG》2007,15(2):250-253
Nonsyndromic mental retardation (NSMR) is the diagnosis of exclusion in mentally retarded individuals without additional abnormalities. We have recently identified a protein-truncating mutation, G408fsX437, in the gene CC2D1A on chromosome 19p13.12 in nine consanguineous Israeli Arab families with severe autosomal recessive NSMR, and have developed a comprehensive prevention program among the at-risk population in the village. The subjects tested were healthy women who were invited to undergo the genetic screening test as a part of their routine pregnancy monitoring. One hundred and seventeen subjects reported a family history positive for mental retardation. We tested 524 pregnant or preconceptional women and found 47 carriers (approximately 1/11), whose spouses were then recommended to undergo testing. We identified eight carrier couples, who were given genetic counseling and offered prenatal diagnosis. Of all the marriages, 28.6% were consanguineous; 16.5% of the total were between first cousins. The high prevalence of the mutation can be explained both by the founder effect owing to the generally high consanguinity rate among the inhabitants of the village, and also because two families with excessive numbers of mentally retarded offspring were unacceptable as marriage partners by the rest of the families. This is the first example of the establishment of a large-scale genetic screening program for autosomal recessive NSMR, which was made possible owing to the high frequency of the specific causative mutation in this isolated population. 相似文献
88.
Waller MW Hallfors DD Halpern CT Iritani BJ Ford CA Guo G 《Archives of women's mental health》2006,9(3):139-150
Summary Objective: This study uses a cluster analysis of adolescents, based on their substance use and sexual risk behaviors, to 1) examine
associations between risk behavior patterns and depressive symptoms, stratified by gender, and 2) examine gender differences
in risk for depression.
Methods: Data are from a nationally representative survey of over 20,000 U.S. adolescents. Logistic regression was used to examine
the associations between 16 risk behavior patterns and current depressive symptoms by gender.
Results: Compared to abstention, involvement in common adolescent risk behaviors (drinking, smoking, and sexual intercourse) was associated
with increased odds of depressive symptoms in both sexes. However, sex differences in depressive symptoms vary by risk behavior
pattern. There were no differences in odds for depressive symptoms between abstaining male and female adolescents (OR = 1.07,
95% CI 0.70–1.62). There were also few sex differences in odds of depressive symptoms within the highest-risk behavior profiles.
Among adolescents showing light and moderate risk behavior patterns, females experienced significantly more depressive symptoms
than males.
Conclusions: Adolescents who engage in risk behaviors are at increased risk for depressive symptoms. Girls engaging in low and moderate
substance use and sexual activity experience more depressive symptoms than boys with similar behavior. Screening for depression
is indicated for female adolescents engaging in even experimental risk behaviors. 相似文献
89.
Liver transplantation with monosegment from a living donor 总被引:3,自引:0,他引:3
Enne M Pacheco-Moreira LF Cerqueira A Balbi E Halpern M Luiz Pereira J Santalucia G Gracia J De Souza E Oliveira FG Paranhos GK Miecznikowski R De Faria LJ Pereira Diaz André R Caroli Bottino A Manoel Martinho J 《Pediatric transplantation》2004,8(2):189-191
The shortage of organ donors for low-weight liver transplant recipients, especially for small children, has led to the development of new surgical techniques to increase the donor pool. Almost all of these techniques use the left lateral segment (Couinaud's segments II and III), but even this graft could be too large for children under 10 kg. We report here the case of an 8-month-old boy, weighing 6.1 kg, who received a monosegmental graft (segment III) from his grandmother weighing 68 kg. The graft was reduced at the donor surgery, before clamping of the vessels. The donor was discharged on the fourth post-operative day; the recipient had an uneventful post-operative period and was discharged after 22 days. 相似文献
90.
Benjamin S. Halpern Sarah E. Lester Karen L. McLeod 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(43):18312-18317
The rapid increase in the science and implementation of marine protected areas (MPAs) around the world in the past 15 years is now being followed by similar increases in the science and application of marine ecosystem-based management (EBM). Despite important overlaps and some common goals, these two approaches have remained either separated in the literature and in conservation and management efforts or treated as if they are one and the same. In the cases when connections are acknowledged, there is often little assessment of if or how well MPAs can achieve specific EBM goals. Here we start by critically evaluating commonalities and differences between MPAs and EBM. Next, we use global analyses to show where and how much no-take marine reserves can be expected to contribute to EBM goals, specifically by reducing the cumulative impacts of stressors on ocean ecosystems. These analyses revealed large stretches of coastal oceans where reserves can play a major role in reducing cumulative impacts and thus improving overall ocean condition, at the same time highlighting the limitations of marine reserves as a single tool to achieve comprehensive EBM. Ultimately, better synergies between these two burgeoning approaches provide opportunities to greatly benefit ocean health. 相似文献