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71.
Christine Keller Nancy E. Wang Daniel L. Imler Shreyas S. Vasanawala Matias Bruzoni James V. Quinn 《The Journal of emergency medicine》2017,52(3):318-323
Background
Ionizing radiation and cost make ultrasound (US), when available, the first imaging study for the diagnosis of suspected pediatric appendicitis. US is less sensitive and specific than computed tomography (CT) or magnetic resonance imaging (MRI) scans, which are often performed after nondiagnostic US.Objectives
We sought to determine predictors of nondiagnostic US in order to guide efficient ordering of imaging studies.Methods
A prospective cohort study of consecutive patients 4 to 30 years of age with suspected appendicitis took place at an emergency department with access to 24/7 US, MRI, and CT capabilities. Patients with US as their initial study were identified. Clinical (i.e., duration of illness, highest fever, and right lower quadrant pain) and demographic (i.e., age and sex) variables were collected. Body mass index (BMI) was calculated based on Centers for Disease Control and Prevention criteria; BMI >85th percentile was categorized as overweight. Patients were followed until day 7. Univariate and stepwise multivariate logistic regression analysis was performed.Results
Over 3 months, 106 patients had US first for suspected appendicitis; 52 (49%) had nondiagnostic US results. Eighteen patients had appendicitis, and there were no missed cases after discharge. On univariate analysis, male sex, a yearly increase in age, and overweight BMI were associated with nondiagnostic US (p < 0.05). In the multivariate model, only BMI (odds ratio 4.9 [95% CI 2.0–12.2]) and age (odds ratio 1.1 [95% CI 1.02–1.20]) were predictors. Sixty-eight percent of nondiagnostic US results occurred in overweight patients.Conclusion
Overweight and older patients are more likely to have a nondiagnostic US or appendicitis, and it may be more efficient to consider alternatives to US first for these patients. Also, this information about the accuracy of US to diagnose suspected appendicitis may be useful to clinicians who wish to engage in shared decision-making with the parents or guardians of children regarding imaging options for children with acute abdominal pain. 相似文献72.
Janey S.A. Pratt Allen Browne Nancy T. Browne Matias Bruzoni Megan Cohen Ashish Desai Thomas Inge Bradley C. Linden Samer G. Mattar Marc Michalsky David Podkameni Kirk W. Reichard Fatima Cody Stanford Meg H. Zeller Jeffrey Zitsman 《Surgery for obesity and related diseases》2018,14(7):882-901
The American Society for Metabolic and Bariatric Surgery Pediatric Committee updated their evidence-based guidelines published in 2012, performing a comprehensive literature search (2009–2017) with 1387 articles and other supporting evidence through February 2018. The significant increase in data supporting the use of metabolic and bariatric surgery (MBS) in adolescents since 2012 strengthens these guidelines from prior reports. Obesity is recognized as a disease; treatment of severe obesity requires a life-long multidisciplinary approach with combinations of lifestyle changes, nutrition, medications, and MBS. We recommend using modern definitions of severe obesity in children with the Centers for Disease Control and Prevention age- and sex-matched growth charts defining class II obesity as 120% of the 95th percentile and class III obesity as 140% of the 95th percentile. Adolescents with class II obesity and a co-morbidity (listed in the guidelines), or with class III obesity should be considered for MBS. Adolescents with cognitive disabilities, a history of mental illness or eating disorders that are treated, immature bone growth, or low Tanner stage should not be denied treatment. MBS is safe and effective in adolescents; given the higher risk of adult obesity that develops in childhood, MBS should not be withheld from adolescents when severe co-morbidities, such as depressed health-related quality of life score, type 2 diabetes, obstructive sleep apnea, and nonalcoholic steatohepatitis exist. Early intervention can reduce the risk of persistent obesity as well as end organ damage from long standing co-morbidities. 相似文献
73.
Caroline F. Ortmann Gislaine Z. Réus Zuleide M. Ignácio Helena M. Abelaira Stephanie E. Titus Pâmela de Carvalho Camila O. Arent Maria Augusta B. dos Santos Beatriz I. Matias Maryane M. Martins Angela M. de Campos Fabricia Petronilho Leticia J. Teixeira Meline O. S. Morais Emilio L. Streck João Quevedo Flávio H. Reginatto 《Neurotoxicity research》2016,29(4):469-483
The purpose of this study was to assess the effect of an enriched C-glycosyl flavonoids fraction (EFF-Cp) from Cecropia Pachystachya leaves on behavior, mitochondrial chain function, and oxidative balance in the brain of rats subjected to chronic mild stress. Male Wistar rats were divided into experimental groups (saline/no stress, saline/stress, EFF-Cp/no stress, and EFF-Cp/stress). ECM groups were submitted to stress for 40 days. On the 35th ECM day, EFF-Cp (50 mg/kg) or saline was administrated and the treatments lasted until the 42nd day. On the 41st and 42nd days, the animals were submitted to the splash test and the forced swim test. After these behavioral tests, the enzymatic activity of mitochondrial chain complexes and oxidative stress were analyzed. EFF-Cp reversed the depressive-like behavior induced by ECM. It also reversed the increase in thiobarbituric acid reactive species, myeloperoxidase activity, and nitrite/nitrate concentrations in some brain regions. The reduced activities of the antioxidants superoxide dismutase and catalase in some brain regions were also reversed by EFF-Cp. The most pronounced effect of EFF-Cp on mitochondrial complexes was an increase in complex IV activity in all studied regions. Thus, it is can be concluded that EFF-Cp exerts an antidepressant-like effect and that oxidative balance may be an important physiological process underlying these effects. 相似文献
74.
75.
Zhu Y Fariña JB Meshack S Santoveña A Patel S Oliva A Llabrés M Hodsdon ME Booth CJ Dannies PS 《Endocrine》2010,37(3):430-439
Women with ovarian cancer have a low survival rate and develop resistance to chemotherapy, so new approaches to treatment are needed. We unexpectedly found administration of a replication-deficient adenovirus containing human growth hormone sequences (AdXGH) was beneficial in a mouse model of human ovarian cancer. Intraperitoneal injections of AdXGH prolonged median survival from a mean of 31?±?1.2 to 40?±?1.4?days in immunodeficient SCID mice given SKOV3.ip1 human ovarian cancer cells in the peritoneal cavity. Adenovirus containing human prolactin or del32-71growth hormone sequences had no effect. Repeated injection of growth hormone or implantation of tablets with sustained growth hormone release did not increase survival. Control mice had overlapping tumors throughout the peritoneal cavity and liver and frequent lung metastases 24?days after tumor cell injection. Mice that received two injections of AdXGH had no lung metastases. Mice that received four injections had no lung or liver metastases and peritoneal fibrosis. They did not survive longer than mice that received two injections, but they had enlarged livers with hepatocellular changes, indicating that a limitation of increasing the dose is liver toxicity. 相似文献
76.
Ericka Barbosa Trarbach Milena Gurgel Teles Elaine Maria Frade Costa Ana Paula Abreu Heraldo Mendes Garmes Gil Guerra Junior Maria Tereza Matias Baptista Margaret De Castro Berenice Bilharinho Mendonca Ana Claudia Latronico 《Clinical endocrinology》2010,72(3):371-376
Objective Congenital hypogonadotropic hypogonadism with anosmia (Kallmann syndrome) or with normal sense of smell is a heterogeneous genetic disorder caused by defects in the synthesis, secretion and action of gonadotrophin‐releasing hormone (GnRH). Mutations involving autosomal genes have been identified in approximately 30% of all cases of hypogonadotropic hypogonadism. However, most studies that screened patients with hypogonadotropic hypogonadism for gene mutations did not include gene dosage methodologies. Therefore, it remains to be determined whether patients without detected point mutation carried a heterozygous deletion of one or more exons. Measurements We used the multiplex ligation‐dependent probe amplification (MLPA) assay to evaluate the potential contribution of heterozygous deletions of FGFR1, GnRH1, GnRHR, GPR54 and NELF genes in the aetiology of GnRH deficiency. Patients We studied a mutation‐negative cohort of 135 patients, 80 with Kallmann syndrome and 55 with normosmic hypogonadotropic hypogonadism. Results One large heterozygous deletion involving all FGFR1 exons was identified in a female patient with sporadic normosmic hypogonadotropic hypogonadism and mild dimorphisms as ogival palate and cavus foot. FGFR1 hemizygosity was confirmed by gene dosage with comparative multiplex and real‐time PCRs. Conclusions FGFR1 or other autosomal gene deletion is a possible but very rare event and does not account for a significant number of sporadic or inherited cases of isolated GnRH deficiency. 相似文献
77.
Pelaez-Coca M Bossa M Olmos S;Alzheimer's Disease Neuroimaging Initiative 《Neuroscience letters》2011,487(1):113-117
This work is a feature-extraction and classification study between Alzheimer's disease (AD) patients and normal subjects. Voxel-wise morphological features of brain MRI are defined as the Jacobian determinants that measure the local volume change between each subject and a given atlas. The goal of this work is to determine the region of interest (ROI) which is best suited for classification. Two types of ROIs are considered: anatomical regions, that were automatically segmented in the atlas (amygdalae, hippocampi and lateral ventricles); and statistical regions, defined from group comparison statistical maps. Classification performance was assessed with five classifiers on 20 pairs of matched training and test groups of subjects from the ADNI database. In this study the statistical masks provided the best classification performance. 相似文献
78.
Tolazzi AR Tolazzi KD Garcia M Graf RM Freitas RS Baretta GA Matias JE Campos AC 《Aesthetic plastic surgery》2009,33(1):84-89
Background Wound contractures can cause severe deformities and disabilities. Recent studies have suggested that leukotriene receptor
antagonists have an inhibitory effect on the healing contraction process. This study aimed to evaluate the influence of the
leukotriene inhibitor montelukast on the cutaneous healing process and the wound contraction phenomenon in rats.
Methods For this study, 60 male rats were randomly divided into four groups (MK-7d, SF-7d, MK-14d, and SF-14d) according to the drug
given through a rigid orogastric tube (MK group: montelukast 10 mg/kg/day; SF group: normal saline solution) and the day the
animals were killed (7d: postoperative day 7; 14d: postoperative day 14). An excisional wound (2 × 2 cm) was created on the
dorsum of each rat. The wounds were left open to heal spontaneously and documented by standard digital photographs on different
postoperative days. Wound contraction rates were calculated with specific software, and specimens were histologically evaluated
using picrosirius red stain. Results were analyzed using the Aspin-Welch, Mann–Whitney, and t tests, assuming a significance level of 5%.
Results The wound contraction rates were similar between the control and study groups (p > 0.05). On postoperative day 7, the wounds showed a marginally significant reduction in collagen maturation in the study
group (40.1% ± 6.88% vs 61.2% ± 8.02%; p = 0.0607). On postoperative day 14, this reduction was statistically significant in the MK group (26% ± 5.66% vs 68.3% ± 7.76%;
p = 0.0001).
Conclusions Montelukast does not alter the contraction rate of excisional wounds in rats but has a significant and progressive inhibitory
effect on collagen maturation.
This study was developed by the Post-Graduate Program in Surgery and Plastic and Reconstructive Surgery Unit of Federal University
of Paraná, Curitiba, Brazil. 相似文献
79.
Tognetti VB Zurbriggen MD Morandi EN Fillat MF Valle EM Hajirezaei MR Carrillo N 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(27):11495-11500
Iron limitation affects one-third of the cultivable land on Earth and represents a major concern for agriculture. It causes decline of many photosynthetic components, including the Fe-S protein ferredoxin (Fd), involved in essential oxidoreductive pathways of chloroplasts. In cyanobacteria and some algae, Fd down-regulation under Fe deficit is compensated by induction of an isofunctional electron carrier, flavodoxin (Fld), a flavin mononucleotide-containing protein not found in plants. Transgenic tobacco lines expressing a cyanobacterial Fld in chloroplasts were able to grow in Fe-deficient media that severely compromised survival of WT plants. Fld expression did not improve Fe uptake or mobilization, and stressed transformants elicited a normal deficit response, including induction of ferric-chelate reductase and metal transporters. However, the presence of Fld did prevent decrease of several photosynthetic proteins (but not Fd) and partially protected photosynthesis from inactivation. It also preserved the activation state of enzymes depending on the Fd-thioredoxin pathway, which correlated with higher levels of intermediates of carbohydrate metabolism and the Calvin cycle, as well as increased contents of sucrose, glutamate, and other amino acids. These metabolic routes depend, directly or indirectly, on the provision of reduced Fd. The results indicate that Fld could compensate Fd decline during episodes of Fe deficiency by productively interacting with Fd-dependent pathways of the host, providing fresh genetic resources for the design of plants able to survive in Fe-poor lands. 相似文献