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1.
J Am Coll Surg ; 238(5): 801-807, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372360

RESUMO

BACKGROUND: Nonaccidental trauma (NAT), or child abuse, is a leading cause of childhood injury and death in the US. Studies demonstrate that military-affiliated individuals are at greater risk of mental health complication and family violence, including child maltreatment. There is limited information about the outcomes of military children who experience NAT. This study compares the outcomes between military-dependent and civilian children diagnosed with NAT. STUDY DESIGN: A single-institution, retrospective review of children admitted with confirmed NAT at a Level I trauma center was performed. Data were collected from the institutional trauma registry and the Child Abuse Team's database. Military affiliation was identified using insurance status and parental or caregiver self-reported active-duty status. Demographic and clinical data including hospital length of stay (LOS), morbidity, specialty consult, and mortality were compared. RESULTS: Among 535 patients, 11.8% (n = 63) were military-affiliated. The median age of military-associated patients, 3 months (interquartile range [IQR] 1 to 7), was significantly younger than civilian patients, 7 months (IQR 3 to 18, p < 0.001). Military-affilif:ated patients had a longer LOS of 4 days (IQR 2 to 11) vs 2 days (IQR 1 to 7, p = 0.041), increased morbidity or complication (3 vs 2 counts, p = 0.002), and a higher mortality rate (10% vs 4%, p = 0.048). No significant difference was observed in the number of consults or injuries, trauma activation, or need for surgery. CONCLUSIONS: Military-affiliated children diagnosed with NAT experience more adverse outcomes than civilian patients. Increased LOS, morbidity or complication, and mortality suggest military-affiliated patients experience more life-threatening NAT at a younger age. Larger studies are required to further examine this population and better support at-risk families.


Assuntos
Maus-Tratos Infantis , Militares , Criança , Humanos , Lactente , Maus-Tratos Infantis/diagnóstico , Estudos Retrospectivos , Hospitalização , Tempo de Internação , Centros de Traumatologia
2.
ACS Cent Sci ; 10(1): 28-42, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38292606

RESUMO

Chemiluminescence is a fascinating phenomenon that involves the generation of light through chemical reactions. The light emission from adamantyl-phenoxy-1,2-dioxetanes can glow from minutes to hours depending on the specific substituent present on the dioxetane molecule. In order to improve the light emission properties produced by these chemiluminescent luminophores, it is necessary to induce the chemiexcitation rate to a flash mode, wherein the bulk of light is emitted instantly rather than slowly over time. We report the realization of this goal through the incorporation of spirostrain release into the decomposition of 1,2-dioxetane luminophores. DFT computational simulations provided support for the hypothesis that the spiro-cyclobutyl substituent accelerates chemiexcitation as compared to the unstrained adamantyl substituent. Spiro-linking of cyclobutane and oxetane units led to greater than 100-fold and 1000-fold emission enhancement, respectively. This accelerated chemiexcitation rate increases the detection sensitivity for known chemiluminescent probes to the highest signal-to-noise ratio documented to date. A turn-ON probe, containing a spiro-cyclobutyl unit, for detecting the enzyme ß-galactosidase exhibited a limit of detection value that is 125-fold more sensitive than that for the previously described adamantyl analogue. This probe was also able to instantly detect and image ß-gal activity with enhanced sensitivity in E. coli bacterial assays.

3.
J Pediatr Surg ; 59(1): 80-85, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37858394

RESUMO

PURPOSE: We explored the application of a machine learning algorithm for the timely detection of potential abusive head trauma (AHT) using the first free-text note of an encounter and demographic information. METHODS: First free-text physician notes and demographic information were collected for children under 5 years of age at a Level 1 Trauma Center. The control group, which included patients with head/neck injury, was compared to those with AHT diagnosed by the Child Protective Team. Differential scores accounted for words overrepresented in AHT patient vs. control notes. Sentiment scores were reflective of note positivity/negativity and subjectivity scores accounted for note subjectivity/objectivity. The composite scores reflected the patient's differential score modified by the subjectivity score. Composite, sentiment, and subjectivity scores combined with demographic information trained a Random Forest (RF) machine learning algorithm to predict AHT. RESULTS: Final composite scores with demographic information were highly associated with AHT in a test dataset. The control group included 587 patients and the test group included 193 patients. Combining composite scores with demographic information into the RF model improved AHT classification area under the curve (AUC) from 0.68 to 0.78, with an overall accuracy of 84%. Feature importance analysis of our RF model revealed that composite score, sentiment, age, and subjectivity were the most impactful predictors of AHT. The sentiment was not significantly different between control and AHT notes (p = 0.87), while subjectivity trended higher for AHT notes (p = 0.081). CONCLUSION: We conclude that a machine learning algorithm can recognize patterns within free-text notes and demographic information that aid in AHT detection in children. LEVEL OF EVIDENCE: III.


Assuntos
Maus-Tratos Infantis , Traumatismos Craniocerebrais , Criança , Humanos , Lactente , Pré-Escolar , Maus-Tratos Infantis/diagnóstico , Estudos Retrospectivos , Traumatismos Craniocerebrais/diagnóstico , Diagnóstico Diferencial , Algoritmos
4.
Chemistry ; 29(25): e202300422, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36779696

RESUMO

Chemiexcitation of phenoxy-1,2-dioxetane chemiluminescent luminophores is initiated by electron transfer from a meta-positioned phenolate ion to the peroxide-dioxetane bond. Here we report the development of a unique 1,2-dioxetane chemiluminescent scaffold with chemiexcitation gated by an OR logic dual-set of triggering events. This scaffold is composed of meta-dihydroxyphenyl-1,2-dioxetane-adamantyl molecules, equipped with acrylic acid and chlorine substituents, that chemiexcitation under physiological conditions. A dual-mode chemiluminescent probe, armed with two different triggering substrates designed for activation by the enzymes ß-galactosidase and alkaline phosphatase, was synthesized. The probe emitted intense light signals in the response to each enzyme, demonstrating its ability to serve as a single-component chemiluminescent sensor for dual-analyte detection. We also demonstrated the ability of the probe to detect ß-galactosidase and phosphatase activities in bacteria. This is the first 1,2-dioxetane scaffold capable of responding to two different chemiexcitation events from two different positions on the same dioxetane molecule. We anticipate that the OR-gated mode of chemiexcitation, described herein, will find utility in the preparation of chemiluminescent probes with a dual-analyte detection/imaging mode.


Assuntos
Fosfatase Alcalina , Medições Luminescentes , Medições Luminescentes/métodos , beta-Galactosidase , Corantes , Fenóis
5.
RNA ; 28(10): 1325-1336, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35961752

RESUMO

Death associated protein 5 (DAP5/eIF4G2/NAT1) is a member of the eIF4G translation initiation factors that has been shown to mediate noncanonical and/or cap-independent translation. It is essential for embryonic development and for differentiation of embryonic stem cells (ESCs), specifically its ability to drive translation of specific target mRNAs. In order to expand the repertoire of DAP5 target mRNAs, we compared ribosome profiles in control and DAP5 knockdown (KD) human ESCs (hESCs) to identify mRNAs with decreased ribosomal occupancy upon DAP5 silencing. A cohort of 68 genes showed decreased translation efficiency in DAP5 KD cells. Mass spectrometry confirmed decreased protein abundance of a significant portion of these targets. Among these was KMT2D, a histone methylase previously shown to be essential for ESC differentiation and embryonic development. We found that nearly half of the cohort of DAP5 target mRNAs displaying reduced translation efficiency of their main coding sequences upon DAP5 KD contained upstream open reading frames (uORFs) that are actively translated independently of DAP5. This is consistent with previously suggested mechanisms by which DAP5 mediates leaky scanning through uORFs and/or reinitiation at the main coding sequence. Crosslinking protein-RNA immunoprecipitation experiments indicated that a significant subset of DAP5 mRNA targets bound DAP5, indicating that direct binding between DAP5 protein and its target mRNAs is a frequent but not absolute requirement for DAP5-dependent translation of the main coding sequence. Thus, we have extended DAP5's function in translation of specific mRNAs in hESCs by a mechanism allowing translation of the main coding sequence following upstream translation of short ORFs.


Assuntos
Fator de Iniciação Eucariótico 4G/metabolismo , Células-Tronco Embrionárias Humanas , Histona Metiltransferases/genética , Histona Metiltransferases/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Fases de Leitura Aberta/genética , Biossíntese de Proteínas , Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Am J Public Health ; 110(10): 1466-1471, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32816548

RESUMO

Objectives. To review the trends in pregnancy outcomes after Hurricane Katrina and assess effects of the disaster on research and public health related to pregnant women.Methods. We reexamined the 2004-2006 vital statistics data from Alabama, Louisiana, and Mississippi, assessing what the risk of adverse pregnancy outcomes in the population would have been under varying risk scenarios.Results. We saw a reduction in number of births as well as in low birth weight and preterm birth. If the number of births had stayed constant and the relative higher risk in the "missing" births had been between 17% and 100%, the storm would have been associated with an increased risk instead of a decrease. Because the relative decline in births was larger in Black women, the higher risk in the "missing" births required to create a significant increase associated with the storm was generally not as great as for White women.Conclusions. Higher exposure to Katrina may have produced a reduction in births among high-risk women in the region rather than increasing adverse outcomes among those who did give birth.


Assuntos
Coeficiente de Natalidade , Resultado da Gravidez , Medição de Risco , Alabama/epidemiologia , Coeficiente de Natalidade/etnologia , Coeficiente de Natalidade/tendências , Tempestades Ciclônicas/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Louisiana/epidemiologia , Mississippi/epidemiologia , Gravidez , Resultado da Gravidez/epidemiologia , Resultado da Gravidez/etnologia , Saúde Pública
7.
Genes Dev ; 30(17): 1991-2004, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27664238

RESUMO

Multiple transcriptional and epigenetic changes drive differentiation of embryonic stem cells (ESCs). This study unveils an additional level of gene expression regulation involving noncanonical, cap-independent translation of a select group of mRNAs. This is driven by death-associated protein 5 (DAP5/eIF4G2/NAT1), a translation initiation factor mediating IRES-dependent translation. We found that the DAP5 knockdown from human ESCs (hESCs) resulted in persistence of pluripotent gene expression, delayed induction of differentiation-associated genes in different cell lineages, and defective embryoid body formation. The latter involved improper cellular organization, lack of cavitation, and enhanced mislocalized apoptosis. RNA sequencing of polysome-associated mRNAs identified candidates with reduced translation efficiency in DAP5-depleted hESCs. These were enriched in mitochondrial proteins involved in oxidative respiration, a pathway essential for differentiation, the significance of which was confirmed by the aberrant mitochondrial morphology and decreased oxidative respiratory activity in DAP5 knockdown cells. Further analysis identified the chromatin modifier HMGN3 as a cap-independent DAP5 translation target whose knockdown resulted in defective differentiation. Thus, DAP5-mediated translation of a specific set of proteins is critical for the transition from pluripotency to differentiation, highlighting the importance of cap-independent translation in stem cell fate decisions.


Assuntos
Diferenciação Celular/genética , Fator de Iniciação Eucariótico 4G/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Células-Tronco Embrionárias Humanas/citologia , Apoptose/genética , Corpos Embrioides/patologia , Fator de Iniciação Eucariótico 4G/genética , Técnicas de Silenciamento de Genes , Proteínas HMGN/genética , Proteínas HMGN/metabolismo , Humanos , Células-Tronco Pluripotentes/fisiologia
8.
Arch Phys Med Rehabil ; 97(10): 1696-705, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27465752

RESUMO

OBJECTIVE: To assess cardiometabolic syndrome (CMS) risk definitions in spinal cord injury/disease (SCI/D). DESIGN: Cross-sectional analysis of a pooled sample. SETTING: Two SCI/D academic medical and rehabilitation centers. PARTICIPANTS: Baseline data from subjects in 7 clinical studies were pooled; not all variables were collected in all studies; therefore, participant numbers varied from 119 to 389. The pooled sample included men (79%) and women (21%) with SCI/D >1 year at spinal cord levels spanning C3-T2 (American Spinal Injury Association Impairment Scale [AIS] grades A-D). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We computed the prevalence of CMS using the American Heart Association/National Heart, Lung, and Blood Institute guideline (CMS diagnosis as sum of risks ≥3 method) for the following risk components: overweight/obesity, insulin resistance, hypertension, and dyslipidemia. We compared this prevalence with the risk calculated from 2 routinely used nonguideline CMS risk assessments: (1) key cut scores identifying insulin resistance derived from the homeostatic model 2 (HOMA2) method or quantitative insulin sensitivity check index (QUICKI), and (2) a cardioendocrine risk ratio based on an inflammation (C-reactive protein [CRP])-adjusted total cholesterol/high-density lipoprotein cholesterol ratio. RESULTS: After adjustment for multiple comparisons, injury level and AIS grade were unrelated to CMS or risk factors. Of the participants, 13% and 32.1% had CMS when using the sum of risks or HOMA2/QUICKI model, respectively. Overweight/obesity and (pre)hypertension were highly prevalent (83% and 62.1%, respectively), with risk for overweight/obesity being significantly associated with CMS diagnosis (sum of risks, χ(2)=10.105; adjusted P=.008). Insulin resistance was significantly associated with CMS when using the HOMA2/QUICKI model (χ(2)2=21.23, adjusted P<.001). Of the subjects, 76.4% were at moderate to high risk from elevated CRP, which was significantly associated with CMS determination (both methods; sum of risks, χ(2)2=10.198; adjusted P=.048 and HOMA2/QUICKI, χ(2)2=10.532; adjusted P=.04). CONCLUSIONS: As expected, guideline-derived CMS risk factors were prevalent in individuals with SCI/D. Overweight/obesity, hypertension, and elevated CRP were common in SCI/D and, because they may compound risks associated with CMS, should be considered population-specific risk determinants. Heightened surveillance for risk, and adoption of healthy living recommendations specifically directed toward weight reduction, hypertension management, and inflammation control, should be incorporated as a priority for disease prevention and management.


Assuntos
Síndrome Metabólica/epidemiologia , Doenças da Medula Espinal/epidemiologia , Traumatismos da Medula Espinal/epidemiologia , Adolescente , Adulto , Idoso , Pressão Sanguínea , Peso Corporal , Estudos Transversais , Feminino , Hemoglobinas Glicadas , Humanos , Mediadores da Inflamação/sangue , Resistência à Insulina , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Fatores de Risco , Traumatismos da Medula Espinal/classificação , Índices de Gravidade do Trauma , Adulto Jovem
9.
Nucleic Acids Res ; 43(7): 3764-75, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25779044

RESUMO

Initiation is a highly regulated rate-limiting step of mRNA translation. During cap-dependent translation, the cap-binding protein eIF4E recruits the mRNA to the ribosome. Specific elements in the 5'UTR of some mRNAs referred to as Internal Ribosome Entry Sites (IRESes) allow direct association of the mRNA with the ribosome without the requirement for eIF4E. Cap-independent initiation permits translation of a subset of cellular and viral mRNAs under conditions wherein cap-dependent translation is inhibited, such as stress, mitosis and viral infection. DAP5 is an eIF4G homolog that has been proposed to regulate both cap-dependent and cap-independent translation. Herein, we demonstrate that DAP5 associates with eIF2ß and eIF4AI to stimulate IRES-dependent translation of cellular mRNAs. In contrast, DAP5 is dispensable for cap-dependent translation. These findings provide the first mechanistic insights into the function of DAP5 as a selective regulator of cap-independent translation.


Assuntos
Fator de Iniciação 2B em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Biossíntese de Proteínas , Ribossomos/metabolismo , Células HEK293 , Humanos , Capuzes de RNA
10.
RNA ; 16(2): 364-74, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20040590

RESUMO

Heat shock proteins (HSPs) provide a useful system for studying developmental patterns in the digenetic Leishmania parasites, since their expression is induced in the mammalian life form. Translation regulation plays a key role in control of protein coding genes in trypanosomatids, and is directed exclusively by elements in the 3' untranslated region (UTR). Using sequential deletions of the Leishmania Hsp83 3' UTR (888 nucleotides [nt]), we mapped a region of 150 nt that was required, but not sufficient for preferential translation of a reporter gene at mammalian-like temperatures, suggesting that changes in RNA structure could be involved. An advanced bioinformatics package for prediction of RNA folding (UNAfold) marked the regulatory region on a highly probable structural arm that includes a polypyrimidine tract (PPT). Mutagenesis of this PPT abrogated completely preferential translation of the fused reporter gene. Furthermore, temperature elevation caused the regulatory region to melt more extensively than the same region that lacked the PPT. We propose that at elevated temperatures the regulatory element in the 3' UTR is more accessible to mediators that promote its interaction with the basal translation components at the 5' end during mRNA circularization. Translation initiation of Hsp83 at all temperatures appears to proceed via scanning of the 5' UTR, since a hairpin structure abolishes expression of a fused reporter gene.


Assuntos
Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Leishmania/genética , Leishmania/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , RNA de Protozoário/genética , RNA de Protozoário/metabolismo , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Animais , Animais Geneticamente Modificados , Sequência de Bases , Primers do DNA/genética , Genes Reporter , Leishmania mexicana/genética , Leishmania mexicana/metabolismo , Modelos Moleculares , Conformação de Ácido Nucleico , Biossíntese de Proteínas , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Protozoário/química , Temperatura
11.
J Appl Physiol (1985) ; 102(3): 1057-64, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17095644

RESUMO

In this study we present a noninvasive method that enables the investigation of the fetal heart rate (FHR) fluctuations. The objective was to design a quantitative measurement to assess the fetal autonomic nervous system and to investigate its development as a function of the gestational age. Our Medical Physics group has developed a complex algorithm for online beat-to-beat detection of the fetal ECG (FECG), extracted from the maternal abdominal ECG signal. We used our previously acquired FECG data, which includes noninvasive recordings of 200 maternal abdominal ECG signals. From these, we chose 35 cases of healthy pregnancies that we divided into three groups according to gestational age: Group 1, 23 +/- 2 wk; Group 2, 32 +/- 1 wk; and Group 3, 39 +/- 1 wk. The FHR variability was analyzed by a time-frequency decomposition based on a continuous wavelet transform. We showed that, independent of the gestational age, most of the FHR power is concentrated in the very-low-frequency range (0.02-0.08 Hz) and in the low-frequency range (0.08-0.2 Hz). In addition, there is power in the high-frequency range that correlates with the frequency range of fetal respiratory motion (0.4-1.7 Hz). In the intermediate-frequency range (0.2-0.4 Hz), the power is significantly smaller. The changes in the average power spectrum in relation to gestation time were carefully and quantitatively examined. The results imply that there is a neural organization during the last trimester of the pregnancy, and the sympathovagal balance is reduced with the gestational age.


Assuntos
Sistema Nervoso Autônomo/embriologia , Eletrocardiografia/métodos , Monitorização Fetal/métodos , Frequência Cardíaca Fetal/fisiologia , Algoritmos , Feminino , Idade Gestacional , Humanos , Gravidez
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