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961.

OBJECTIVE:

Atrial fibrillation is a common arrhythmia that increases the risk of stroke by four- to five-fold. We aimed to establish a profile of patients with atrial fibrillation from a population of patients admitted with acute ischemic stroke or transient ischemic attack using clinical and echocardiographic findings.

METHODS:

We evaluated patients consecutively admitted to a tertiary hospital with acute ischemic stroke or transient ischemic attack. Subjects were divided into an original set (admissions from May 2009 to October 2010) and a validation set (admissions from November 2010 to April 2013). The study was designed as a cohort, with clinical and echocardiographic findings compared between patients with and without atrial fibrillation. A multivariable model was built, and independent predictive factors were used to produce a predictive grading score for atrial fibrillation (Acute Stroke AF Score-ASAS).

RESULTS:

A total of 257 patients were evaluated from May 2009 to October 2010 and included in the original set. Atrial fibrillation was diagnosed in 17.5% of these patients. Significant predictors of atrial fibrillation in the multivariate analysis included age, National Institutes of Health Stroke Scores, and the presence of left atrial enlargement. These predictors were used in the final logistic model. For this model, the area under the receiver operating characteristic curve was 0.79. The score derived from the logistic regression analysis was The model developed from the original data set was then applied to the validation data set, showing the preserved discriminatory ability of the model (c statistic = 0.76).

CONCLUSIONS:

Our risk score suggests that the individual risk for atrial fibrillation in patients with acute ischemic stroke can be assessed using simple data, including age, National Institutes of Health Stroke Scores at admission, and the presence of left atrial enlargement.  相似文献   
962.
The rapid identification of bacteria and fungi directly from the blood of patients with suspected bloodstream infections aids in diagnosis and guides treatment decisions. The development of an automated, rapid, and sensitive molecular technology capable of detecting the diverse agents of such infections at low titers has been challenging, due in part to the high background of genomic DNA in blood. PCR followed by electrospray ionization mass spectrometry (PCR/ESI-MS) allows for the rapid and accurate identification of microorganisms but with a sensitivity of about 50% compared to that of culture when using 1-ml whole-blood specimens. Here, we describe a new integrated specimen preparation technology that substantially improves the sensitivity of PCR/ESI-MS analysis. An efficient lysis method and automated DNA purification system were designed for processing 5 ml of whole blood. In addition, PCR amplification formulations were optimized to tolerate high levels of human DNA. An analysis of 331 specimens collected from patients with suspected bloodstream infections resulted in 35 PCR/ESI-MS-positive specimens (10.6%) compared to 18 positive by culture (5.4%). PCR/ESI-MS was 83% sensitive and 94% specific compared to culture. Replicate PCR/ESI-MS testing from a second aliquot of the PCR/ESI-MS-positive/culture-negative specimens corroborated the initial findings in most cases, resulting in increased sensitivity (91%) and specificity (99%) when confirmed detections were considered true positives. The integrated solution described here has the potential to provide rapid detection and identification of organisms responsible for bloodstream infections.  相似文献   
963.
Leishmania amazonensis is one of the major etiologic agents of a broad spectrum of clinical forms of leishmaniasis and has a wide geographical distribution in the Americas, which overlaps with the areas of transmission of many other Leishmania species. The LACK and A2 antigens are shared by various Leishmania species. A2 was previously shown to induce a potent Th1 immune response and protection against L. donovani infection in BALB/c mice. LACK is effective against L. major infection, but no significant protection against L. donovani infection was observed, in spite of the induction of a potent Th1 immune response. In an attempt to select candidate antigens for an American leishmaniasis vaccine, we investigated the protective effect of these recombinant antigens (rLACK and rA2) and recombinant interleukin-12 (rIL-12) against L. amazonensis infection in BALB/c mice. As expected, immunization with either rA2-rIL-12 or rLACK-rIL-12 induced a robust Th1 response prior to infection. However, only the BALB/c mice immunized with rA2-rIL-12 were protected against infection. Sustained gamma interferon (IFN-gamma) production, high levels of anti-A2 antibodies, and low levels of parasite-specific antibodies were detected in these mice after infection. In contrast, mice immunized with rLACK-rIL-12 displayed decreased levels of IFN-gamma and high levels of both anti-LACK and parasite-specific antibodies. Curiously, the association between rA2 and rLACK antigens in the same vaccine completely inhibited the rA2-specific IFN-gamma and humoral responses and, consequently, the protective effect of the rA2 antigen against L. amazonensis infection. We concluded that A2, but not LACK, fits the requirements for a safe vaccine against American leishmaniasis.  相似文献   
964.
Endemic pemphigus foliaceus (EPF) is an autoimmune disease characterized by blister formation with a loss of cohesion and infiltration of inflammatory cells. We observed that supernatants of peripheral blood mononuclear cells from patients produced significantly more interleukin-1beta (IL-1beta) than those from stimulated healthy controls. Furthermore, a Th2 bias was observed in EPF patients when the IL-5/gamma interferon ratio was analyzed. These results indicate that cells from pemphigus patients react with a vigorous proinflammatory response.  相似文献   
965.

Study Objectives:

To test the effects of exercise training on sleep and neurovascular control in patients with systolic heart failure with and without sleep disordered breathing.

Design:

Prospective interventional study.

Setting:

Cardiac rehabilitation and exercise physiology unit and sleep laboratory.

Patients:

Twenty-five patients with heart failure, aged 42 to 70 years, and New York Heart Association Functional Class I-III were divided into 1 of 3 groups: obstructive sleep apnea (n = 8), central sleep apnea (n = 9) and no sleep apnea (n = 7).

Interventions:

Four months of no-training (control) followed by 4 months of an exercise training program (three 60-minute, supervised, exercise sessions per week).

Measures and Results:

Sleep (polysomnography), microneurography, forearm blood flow (plethysmography), peak VO2, and quality of life were evaluated at baseline and at the end of the control and trained periods. No significant changes occurred in the control period. Exercise training reduced muscle sympathetic nerve activity (P < 0.001) and increased forearm blood flow (P < 0.01), peak VO2(P < 0.01), and quality of life (P < 0.01) in all groups, independent of the presence of sleep apnea. Exercise training improved the apnea-hypopnea index, minimum O2 saturation, and amount stage 3-4 sleep (P < 0.05) in patients with obstructive sleep apnea but had no significant effects in patients with central sleep apnea.

Conclusions.

The beneficial effects of exercise training on neurovascular function, functional capacity, and quality of life in patients with systolic dysfunction and heart failure occurs independently of sleep disordered breathing. Exercise training lessens the severity of obstructive sleep apnea but does not affect central sleep apnea in patients with heart failure and sleep disordered breathing.

Citation:

Ueno LM; Drager LF; Rodrigues ACT; Rondon MUPB; Braga AMFW; Mathias W; Krieger EM; Barretto ACP; Middlekauff HR; Lorenzi-Filho G; Negrão CE. Effects of exercise training in patients with chronic heart failure and sleep apnea. SLEEP 2009;32(5):637-647.  相似文献   
966.
We investigated the effects of age and gender on emotional perception and physiology using electrodermal skin conductance response (SCR) and examined whether SCR is related to subjective perceptions of emotional pictures. Older adults found pictures to be more positive and arousing than younger participants. Older women rated pictures more extremely at both ends of the valence continuum: they rated positive pictures more positively and negative pictures more negatively. Elders were less likely to show measurable SCRs. However, magnitude of SCRs when a response occurred did not differ between young and old. Subjective ratings of emotion correlated with physiological responses in younger participants, but they were unrelated in older participants. Thus, in older adults the perception of emotional events was disconnected from the physiological state induced by emotion.  相似文献   
967.
We present a case of malignant ameloblastoma presenting in the posterior mandible and cervical lymph nodes of an African American child. This case is somewhat unusual in that the patient was an adolescent and presented with metastatic disease. This partly clinical as well as cytologic diagnosis was facilitated by the presence of typical ameloblastoma cytology in multiple cervical lymph nodes adjacent to the histologically confirmed intraosseous ameloblastoma. Although cytology is helpful in diagnosing ameloblastoma, its features are by no means definitive as there are several cytologic mimics. A high index of suspicion is therefore necessary to confirm or exclude ameloblastoma when evaluating any jaw lesion and/or adjacent enlarged lymph nodes by cytologic examination. Adequate sampling is paramount to accurate diagnosis, and is especially important when attempting to distinguish ameloblastoma from ameloblastic carcinoma. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
968.
Fanconi anemia (FA) is a rare autosomal recessive or X‐linked disorder characterized by aplastic anemia, cancer susceptibility and cellular sensitivity to DNA crosslinking agents. Eight FA proteins (FANCA, FANCB, FANCC, FANCE, FANCF, FANCG, FANCL and FANCM) and three non‐FA proteins (FAAP100, FAAP24 and HES1) form an FA nuclear core complex, which is required for monoubiquitination of the FANCD2‐FANCI dimer upon DNA damage. FANCL possesses a PHD/RING‐finger domain and is a putative E3 ubiquitin ligase subunit of the core complex. In this study, we report an FA patient with an unusual presentation belonging to the FA‐L complementation group. The patient lacks an obvious FA phenotype except for the presence of a café‐au‐lait spot, mild hypocellularity and a family history of leukemia. The molecular diagnosis and identification of the FA subgroup was achieved by FA complementation assay. We identified bi‐allelic novel mutations in the FANCL gene and functionally characterized them. To the best of our knowledge, this is the second reported case belonging to the FA‐L complementation group. © 2009 Wiley‐Liss, Inc.  相似文献   
969.
IntroductionPriapism is the persistent and painful erection of the penis and is a common sickle cell disease (SCD) complication.AimThe goal of this study was to characterize clinical and genetic factors associated with priapism within a large multi-center SCD cohort in Brazil.MethodsCases with priapism were compared to SCD type-matched controls within defined age strata to identify clinical outcomes associated with priapism. Whole blood single nucleotide polymorphism genotyping was performed using a customized array, and a genome-wide association study (GWAS) was conducted to identify single nucleotide polymorphisms associated with priapism.Main Outcome MeasureOf the 1,314 male patients in the cohort, 188 experienced priapism (14.3%).ResultsPriapism was more common among older patients (P = .006) and more severe SCD genotypes such as homozygous SS (P < .0001). In the genotype- and age-matched analyses, associations with priapism were found for pulmonary hypertension (P = .05) and avascular necrosis (P = .01). The GWAS suggested replication of a previously reported candidate gene association of priapism for the gene transforming growth factor beta receptor 3 (TGFBR3) (P = 2 × 10?4).Clinical ImplicationsOlder patients with more severe genotypes are at higher risk of priapism, and there is a lack of consensus on standard treatment strategies for priapism in SCD.Strengths & LimitationsThis study characterizes SCD patients with any history of priapism from a large multi-center cohort. Replication of the GWAS in an independent cohort is required to validate the results.ConclusionThese findings extend the understanding of risk factors associated with priapism in SCD and identify genetic markers to be investigated in future studies to further elucidate priapism pathophysiology.Ozahata M, Page GP, Guo Y, et al. Clinical and Genetic Predictors of Priapism in Sickle Cell Disease: Results from the Recipient Epidemiology and Donor Evaluation Study III Brazil Cohort Study. J Sex Med 2019;16:1988–1999.  相似文献   
970.
Advances in health care science and delivery, coupled with patient need for access to care, have driven expanded practice in midwifery for decades. The process for development and implementation of expanded practices for midwives and midwifery practices is described. Important components include assessment of need, identifying stakeholders and supporters, development of a program proposal, obtaining privileges, developing training programs, and conducting ongoing quality management and program evaluation. Examples of expanded practice in midwifery are presented.  相似文献   
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