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1.
Spine Deform ; 7(5): 779-787, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31495479

RESUMO

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVES: To identify the effects of preoperative steroid therapy on 30-day perioperative complications after adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: Chronic steroid therapy has demonstrated therapeutic effects in the treatment of various medical conditions but is also known to be associated with surgical complications. There remains a gap in the literature regarding the impact of chronic steroid therapy in predisposing patients to perioperative complications after elective surgery for ASD. METHODS: We performed a retrospective analysis of data from the 2008-2015 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patients were divided into two groups based on preoperative steroid therapy. Differences in baseline patient characteristics, comorbidities, and operative variables were assessed. Univariate analysis was performed to compare the incidence of perioperative complications. Multivariate stepwise logistic regression models were then used to adjust for baseline patient and operative variables in order to identify perioperative complications that were associated with preoperative steroid therapy. RESULTS: We identified 7,936 patients who underwent surgery for ASD, of which 418 (5.3%) were on preoperative steroid therapy. Preoperative steroid therapy was an independent risk factor for four perioperative complications, including mortality (odds ratio [OR] 2.42, 95% confidence interval [CI] 1.30, 4.51; p = .005), wound dehiscence (OR 3.12, 95% CI 1.45, 6.70; p = .004), deep vein thrombosis (DVT) (OR 2.10, 95% CI 1.24, 3.55; p = .006), and blood transfusion (OR 1.34, 95% CI 1.08, 1.66; p < .007). CONCLUSIONS: Patients on preoperative steroid therapy are at increased risk of 30-day mortality, wound dehiscence, DVT, and blood transfusion after surgery for ASD. An interdisciplinary approach to the perioperative management of steroid regimens is critical. LEVEL OF EVIDENCE: Level III.

2.
Anal Bioanal Chem ; 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286179

RESUMO

Graphite electrodes were modified with triangular (AuNTrs) or spherical (AuNPs) nanoparticles and further modified with fructose dehydrogenase (FDH). The present study reports the effect of the shape of these nanoparticles (NPs) on the catalytic current of immobilized FDH pointing out the different contributions on the mass transfer-limited and kinetically limited currents. The influence of the shape of the NPs on the mass transfer-limited and the kinetically limited current has been proved by using two different methods: a rotating disk electrode (RDE) and an electrode mounted in a wall jet flow-through electrochemical cell attached to a flow system. The advantages of using the wall jet flow system compared with the RDE system for kinetic investigations are as follows: no need to account for substrate consumption, especially in the case of desorption of enzyme, and studies of product-inhibited enzymes. The comparison reveals that virtually identical results can be obtained using either of the two techniques. The heterogeneous electron transfer (ET) rate constants (kS) were found to be 3.8 ± 0.3 s-1 and 0.9 ± 0.1 s-1, for triangular and spherical NPs, respectively. The improvement observed for the electrode modified with AuNTrs suggests a more effective enzyme-NP interaction, which can allocate a higher number of enzyme molecules on the electrode surface. Graphical abstract The shape of gold nanoparticles has a crucial effect on the catalytic current related to the oxidation of D-(-)-fructose to 5-keto-D-(-)-fructose occurring at the FDH-modified electrode surface. In particular, AuNTrs have a higher effect compared with the spherical one.

3.
Neurocirugia (Astur) ; 30(5): 222-227, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30975560

RESUMO

INTRODUCTION: There are different techniques for the reconstruction of the temporal muscle (TM) in the pterional approach (PA) in order to avoid and reduce atrophy, it has not been able to avoid it in its entirety. The administration of bupivacaine generates regeneration of muscle fibres. There are no studies in the medical literature that evaluate the time of TM manipulation and the use of bupivacaine for the treatment of atrophy after pterional approach, the present investigation aim is to describe the effects of these variables. PATIENT AND METHODS: Longitudinal study, including patients from 18-80 years old with pterional approach at 2016-2017. We evaluated the effects of the TM manipulation times and the administration of 0.5% bupivacaine on the trophism and function of TM. RESULTS: Twenty-nine patients underwent a PA; 16(55.17%) count with criteria for 0.5% bupivacain infiltration. We found a negative correlation between manipulation times and trophism, with no statistically significance (p>.05). We evaluated presurgical and postsurgical index of Helkimo and Fonseca's index, finding an increase of disfunction with statistically significance (p<.05). In patients who were infiltrated with 0.5% bupivacaine we observed a mean difference in the TM's trophism of 0.275±1.18mm, in contrast with no infiltrated which was 2.39±1.30mm (t[27] = -5.118, p=.0001). CONCLUSIONS: The manipulation of the TM during a pterional approach conditioned an impact on the quality of life according to the disfunction indexes, due to atrophy. This investigation exhibits that de administration of 0.5% bupivacaine during surgery offers a decrease in the TM atrophy.

4.
World Neurosurg ; 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30822580

RESUMO

OBJECTIVE: To examine the effects of chronic preoperative steroid therapy on 30-day perioperative complications after anterior lumbar fusion (ALF). METHODS: We retrospectively analyzed data from the American College of Surgeons National Surgical Quality Improvement Program between 2008 and 2015. Adult patients who underwent ALF were included and divided into 2 groups: steroids and no steroids. We compared baseline patient demographics, comorbidities, and operative variables between these 2 groups and then performed a multivariate regression analysis to determine complications that were independently associated with chronic steroid therapy. We also performed a subgroup analysis of the steroid group to identify additional risk factors that further predispose these patients to postoperative complications. RESULTS: A total of 9483 patients were included, of whom 289 (3.0%) were on chronic steroid therapy. Univariate analysis showed that chronic steroid use was independently associated with 4 perioperative complications, including deep surgical site infection (odds ratio [OR], 2.78; confidence interval [CI], 1.09-7.10; P = 0.033), pulmonary complications (OR, 1.98; CI, 1.02-3.86; P = 0.044), blood transfusion (OR, 1.60; CI, 1.15-2.23; P = 0.005), and extended length of stay (OR, 1.58; CI, 1.17-2.16; P = 0.003). In patients on chronic steroid therapy, pulmonary comorbidity and extended operative time were additional risk factors that further predisposed to perioperative complications, including deep surgical site infection, blood transfusion, and extended length of stay. CONCLUSIONS: Chronic preoperative steroid therapy is associated with perioperative complications after ALF. Decisions about the discontinuing or holding steroid therapy preoperatively should be determined through an interdisciplinary approach between the medical and surgical teams.

5.
Nat Commun ; 9(1): 5229, 2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30523329

RESUMO

Analysis of sleep for the diagnosis of sleep disorders such as Type-1 Narcolepsy (T1N) currently requires visual inspection of polysomnography records by trained scoring technicians. Here, we used neural networks in approximately 3,000 normal and abnormal sleep recordings to automate sleep stage scoring, producing a hypnodensity graph-a probability distribution conveying more information than classical hypnograms. Accuracy of sleep stage scoring was validated in 70 subjects assessed by six scorers. The best model performed better than any individual scorer (87% versus consensus). It also reliably scores sleep down to 5 s instead of 30 s scoring epochs. A T1N marker based on unusual sleep stage overlaps achieved a specificity of 96% and a sensitivity of 91%, validated in independent datasets. Addition of HLA-DQB1*06:02 typing increased specificity to 99%. Our method can reduce time spent in sleep clinics and automates T1N diagnosis. It also opens the possibility of diagnosing T1N using home sleep studies.

6.
Int J Surg Case Rep ; 51: 328-330, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30245355

RESUMO

INTRODUCTION: Brown tumors are non-neoplastic, expansive bone lesions that occur only in the setting of hyperparathyroidism. The most usual localization of brown tumors is in mandible, ribs and large bones. In cervical spine, to date, there are only 11 cases reported. The aim of this work is to report the case of a patient with Wegener´s granulomatosis with secondary end stage renal failure who developed a brown tumor in C4 vertebra. PRESENTATION OF CASE: A 25-year-old woman with an history of 2 months of worsening cervicalgia without history of trauma. She complained about progressive neck pain with irradiation to both shoulders and right arm paresthesias, spontaneous fracture or brown spinal cord tumor were suspected. She presented cervical spine instability, was managed with corpectomy of C4 and biopsy. DISCUSSION: The initial suspicion of this disease must be since the first clinician contact of the patient and with the past medical history of end stage renal failure plus recent neurologic manifestations. The aim of neurosurgical management of these patients is to promote spinal stability and release spinal cord and nerve roots to eliminate risk of neurological deficits. CONCLUSION: The importance of the prompt diagnosis of the brown tumor is to establish a multidisciplinary management to prevent progression, neurologic complications and sequelae despite its benign behavior.

7.
Elife ; 62017 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-28315524

RESUMO

To build a coherent view of the external world, an organism needs to integrate multiple types of sensory information from different sources, a process known as multisensory integration (MSI). Previously, we showed that the temporal dependence of MSI in the optic tectum of Xenopus laevis tadpoles is mediated by the network dynamics of the recruitment of local inhibition by sensory input (Felch et al., 2016). This was one of the first cellular-level mechanisms described for MSI. Here, we expand this cellular level view of MSI by focusing on the principle of inverse effectiveness, another central feature of MSI stating that the amount of multisensory enhancement observed inversely depends on the size of unisensory responses. We show that non-linear summation of crossmodal synaptic responses, mediated by NMDA-type glutamate receptor (NMDARs) activation, form the cellular basis for inverse effectiveness, both at the cellular and behavioral levels.


Assuntos
Percepção Auditiva/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Larva/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Colículos Superiores/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica , Animais , Rede Nervosa/fisiologia , Estimulação Luminosa , Colículos Superiores/anatomia & histologia , Sinapses/fisiologia , Transmissão Sináptica/fisiologia , Xenopus laevis
9.
PLoS One ; 10(9): e0138205, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26356080

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0114565.].

10.
Sleep Med ; 16(12): 1558-66, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26299470

RESUMO

OBJECTIVE: Type 1 narcolepsy/hypocretin deficiency is characterized by excessive daytime sleepiness, sleep fragmentation, and cataplexy. Short rapid eye movement (REM) latency (≤15 min) during nocturnal polysomnography (PSG) or during naps of the multiple sleep latency test (MSLT) defines a sleep-onset REM sleep period (SOREMP), a diagnostic hallmark. We hypothesized that abnormal sleep transitions other than SOREMPs can be identified in type 1 narcolepsy. METHODS: Sleep-stage transitions (one to 10 epochs to one to five epochs of any other stage) and bout length features (one to 10 epochs) were extracted from PSGs. The first 15 min of sleep were excluded when a nocturnal SOREMP was recorded. F(0.1) measures and receiver operating characteristic curves were used to identify specific (≥98%) features. A data set of 136 patients and 510 sex- and age-matched controls was used for the training. A data set of 19 cases and 708 sleep-clinic patients was used for the validation. RESULTS: (1) ≥5 transitions from ≥5 epochs of stage N1 or W to ≥2 epochs of REM sleep, (2) ≥22 transitions from ≥3 epochs of stage N2 or N3 to ≥2 epochs of N1 or W, and (3) ≥16 bouts of ≥6 epochs of N1 or W were found to be highly specific (≥98%). Sensitivity ranged from 16% to 30%, and it did not vary substantially with and without medication or a nocturnal SOREMP. In patients taking antidepressants, nocturnal SOREMPs occurred much less frequently (16% vs. 36%, p < 0.001). CONCLUSIONS: Increased sleep-stage transitions notably from ≥2.5 min of W/N1 into REM are specifically diagnostic for narcolepsy independent of a nocturnal SOREMP.


Assuntos
Narcolepsia/diagnóstico , Polissonografia/métodos , Fases do Sono/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Narcolepsia/fisiopatologia , Orexinas/líquido cefalorraquidiano , Sono REM/fisiologia
11.
PLoS One ; 9(12): e114565, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25489744

RESUMO

Periodic Limb Movements (PLMs) are episodic, involuntary movements caused by fairly specific muscle contractions that occur during sleep and can be scored during nocturnal polysomnography (NPSG). Because leg movements (LM) may be accompanied by an arousal or sleep fragmentation, a high PLM index (i.e. average number of PLMs per hour) may have an effect on an individual's overall health and wellbeing. This study presents the design and validation of the Stanford PLM automatic detector (S-PLMAD), a robust, automated leg movement detector to score PLM. NPSG studies from adult participants of the Wisconsin Sleep Cohort (WSC, n = 1,073, 2000-2004) and successive Stanford Sleep Cohort (SSC) patients (n = 760, 1999-2007) undergoing baseline NPSG were used in the design and validation of this study. The scoring algorithm of the S-PLMAD was initially based on the 2007 American Association of Sleep Medicine clinical scoring rules. It was first tested against other published algorithms using manually scored LM in the WSC. Rules were then modified to accommodate baseline noise and electrocardiography interference and to better exclude LM adjacent to respiratory events. The S-PLMAD incorporates adaptive noise cancelling of cardiac interference and noise-floor adjustable detection thresholds, removes LM secondary to sleep disordered breathing within 5 sec of respiratory events, and is robust to transient artifacts. Furthermore, it provides PLM indices for sleep (PLMS) and wake plus periodicity index and other metrics. To validate the final S-PLMAD, experts visually scored 78 studies in normal sleepers and patients with restless legs syndrome, sleep disordered breathing, rapid eye movement sleep behavior disorder, narcolepsy-cataplexy, insomnia, and delayed sleep phase syndrome. PLM indices were highly correlated between expert, visually scored PLMS and automatic scorings (r²â€Š= 0.94 in WSC and r²â€Š= 0.94 in SSC). In conclusion, The S-PLMAD is a robust and high throughput PLM detector that functions well in controls and sleep disorder patients.


Assuntos
Perna (Membro)/fisiopatologia , Informática Médica/métodos , Movimento , Mioclonia/diagnóstico , Mioclonia/fisiopatologia , Adulto , Algoritmos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Nat Methods ; 11(4): 385-92, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24562424

RESUMO

Sleep spindles are discrete, intermittent patterns of brain activity observed in human electroencephalographic data. Increasingly, these oscillations are of biological and clinical interest because of their role in development, learning and neurological disorders. We used an Internet interface to crowdsource spindle identification by human experts and non-experts, and we compared their performance with that of automated detection algorithms in data from middle- to older-aged subjects from the general population. We also refined methods for forming group consensus and evaluating the performance of event detectors in physiological data such as electroencephalographic recordings from polysomnography. Compared to the expert group consensus gold standard, the highest performance was by individual experts and the non-expert group consensus, followed by automated spindle detectors. This analysis showed that crowdsourcing the scoring of sleep data is an efficient method to collect large data sets, even for difficult tasks such as spindle identification. Further refinements to spindle detection algorithms are needed for middle- to older-aged subjects.


Assuntos
Automação , Crowdsourcing , Eletroencefalografia , Fases do Sono/fisiologia , Idoso , Algoritmos , Humanos , Internet , Pessoa de Meia-Idade
13.
Mov Disord ; 25(14): 2296-303, 2010 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-20976736

RESUMO

The aim of this study was to test the hypothesis that patients with REM sleep behavior disorder, many of whom will develop Parkinson's disease (PD) or a related synucleinopathy, will demonstrate decreased heart rate variability (HRV) compared with a group of age-matched controls as measured by an electrocardiogram during wakefulness. We compared HRV in 11 untreated idiopathic REM sleep behavior disorder patients (9 men and 2 women; mean age, 63.3 years; SD, 7.5 years) and 11 control subjects with idiopathic insomnia without REM sleep behavior disorder (7 men and 4 women; mean age, 59.5 years; SD, 8.7 years). Subjects with other causes of reduced HRV were excluded. HRV was determined from 5-minute presleep segments of a single channel electrocardiogram recorded during polysomnographic evaluations, using R-R intervals during wakefulness. Time domain, geometric measures, and spectral analysis of the R-R intervals were significantly different between cases and controls. A discriminant function analysis correctly classified 95.5% of subjects (overall model fit, P = 0.016). Leave-one-out cross-validation correctly classified 77.3% of subjects. HRV during wakefulness is significantly decreased in patients with idiopathic REM sleep behavior disorder compared with control subjects, suggesting abnormalities of both sympathetic and parasympathetic function. Patients with RBD may later develop motor and cognitive features of a Lewy body disorder, such as PD. Cardiac autonomic dysfunction is also impaired in PD, suggesting that impaired HRV may be an early sign of PD. HRV measured by routine electrocardiograms could be used to screen for Lewy body disorders such as PD.


Assuntos
Eletrocardiografia , Doença de Parkinson/diagnóstico , Transtorno do Comportamento do Sono REM/diagnóstico , Idoso , Doenças do Sistema Nervoso Autônomo/etiologia , Progressão da Doença , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Doença de Parkinson/fisiopatologia , Transtorno do Comportamento do Sono REM/fisiopatologia , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo
14.
Immunology ; 117(2): 220-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16423058

RESUMO

Dendritic cells (DC) are often arranged in planar layers in tissues with high antigenic exposure, such as skin and mucosae. Providing an en face view, this arrangement optimizes in situ analysis regarding morphology (even of individual dendrites), topographic distribution (regular/clustered) and quantification. The few reports on human genital DC usually utilize single markers and conventional sections, restricting immunolabelling only to cell parts sectioned by the cut. To better assess DC in situ, we labelled epithelial sheets, prepared from fresh cervix biopsies, with antibodies to major histocompatibility complex (MHC)-CII, CD1a and Langerin, revealing (with each of these markers) a dense DC network in a planar-like, regular distribution. Using the hybrid capture system to detect the high-risk mucotropic human papilloma virus (HPV) group, 16 positive and five negative women were studied and the results were compared between these groups. DC frequency per area was substantially reduced (to approximately 50% for the three markers) in samples from all HPV-infected patients compared with samples from controls. Unlike HPV(-) samples, Langerin(+) DC in HPV(+) cervix exhibited a highly accentuated dendritic appearance. We believe this to be the first study using these three DC-restricted markers (Langerin, CD1a and MHC-CII) in cervical epithelial sheets from high-risk HPV(+) donors and also the first study to demonstrate the morphological and quantitative changes triggered by high-risk HPV infection. Cervical DC reduction in early, premalignant high-risk HPV infection might represent viral subversion strategies interfering with efficient antigen handling by the immune system's peripheral sentinels, the DC, perhaps hampering appropriate recruitment and subsequent development of effector (cytotoxic) T cells.


Assuntos
Colo do Útero/imunologia , Células Dendríticas/imunologia , Células de Langerhans/imunologia , Papillomaviridae , Infecções por Papillomavirus/imunologia , Proteínas do Capsídeo/metabolismo , Neoplasia Intraepitelial Cervical/imunologia , Neoplasia Intraepitelial Cervical/patologia , Neoplasia Intraepitelial Cervical/virologia , Colo do Útero/anatomia & histologia , Colo do Útero/virologia , Células Dendríticas/patologia , Feminino , Antígenos HLA-DR/análise , Humanos , Técnicas Imunoenzimáticas , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/patologia , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
16.
Rev. méd. IMSS ; 23(5): 393-7, sept.-oct. 1985. tab, mapas
Artigo em Espanhol | LILACS | ID: lil-31854

RESUMO

Se inició un registro regional de tumores malignos, para el sur de Sonora, México, con una población de 750 000 habitantes. Se hizo una pesquisa de cada caso nuevo de cáncer informado por centros hospitalarios, consulta externa y laboratorios de anatomía patológica, así como en certificados de defunción, durante el periodo de 1982 a 1983 (del 15 de marzo al 14 de marzo siguiente). Se informan cifras de cada grupo de tumores por sitio de origen, sexo y decenios de la vida en que se presentan. Se encontraron en total 1 123 casos, o sea una frecuencia de 1 497.3 por obs: 1 000 000 de habitantes por año, y entre éstos se encontraron 570 defunciones, que constituyen una tasa de mortalidad de 760 por obs: 1 000 000 por año. Fueron 490 los casos (43.6%) en varones y 633 (56.4%) en mujeres. La máxima frecuencia ocurrió a partir de los 40 años. El tumor más frecuente fue el del cuello uterino, 246 casos (21.9%), y lo siguieron los de bronquios y pulmón, glándula mamaria, los linfomas, las leucemias y de piel con 130 (11.6%), 92 (8.2%), 90 (8%) y 86 (7.6%) casos, respectivamente


Assuntos
Humanos , Masculino , Feminino , Registros de Doenças , Neoplasias/epidemiologia , Inquéritos Epidemiológicos , México
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