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Due to their widespread production and known environmental contamination, the need for the detection and remediation of per- and polyfluoroalkyl substances (PFAS) has grown quickly. While destructive thermal treatment of PFAS at low temperatures (e.g., 200-500 °C) is of interest due to lower energy and infrastructure requirements, the range of possible degradation products remains underexplored. To better understand the low temperature decomposition of PFAS species, we have coupled gas-phase infrared spectroscopy with a multivariate curve resolution (MCR) analysis and a database of high-resolution PFAS infrared reference spectra to characterize and quantify a complex mixture resulting from potassium perfluorooctanesulfonate (PFOS-K) decomposition. Beginning at 375 °C, nine prevalent decomposition products (namely smaller perfluorocarbon species) are identified and quantified.
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Recuperação e Remediação Ambiental , Fluorocarbonos , Espectrofotometria Infravermelho , Fluorocarbonos/química , Fluorocarbonos/análise , Recuperação e Remediação Ambiental/métodos , Ácidos Alcanossulfônicos/química , Ácidos Alcanossulfônicos/análise , Poluentes Ambientais/química , Poluentes Ambientais/análise , TemperaturaRESUMO
Per- and polyfluoroalkyl substances (PFAS) are synthetic organofluorine compounds known for their chemical and physical stability as well as their wide range of uses. Some PFAS are widely distributed in the environment, leading to concerns related to both environmental and human health. High temperature thermal treatment (i.e., incineration) has been utilized for PFAS treatment, but this requires significant infrastructure and energy, prompting interest in lower temperature approaches that may still lead to efficient destruction. Lower treatment temperatures, however, increase the potential for incomplete PFAS mineralization and formation of volatile organofluorine (VOF) products. Herein, we report the formation of novel VOF products that include chlorinated and brominated compounds during the thermal treatment of potassium perfluorohexane sulfonate (PFHxS), a representative perfluoroalkyl acid (PFAA). By comparing the gas chromatography-mass spectrometry (GC-MS) results of known VOF stocks to evolved VOF during thermal treatment of PFAS, the formation of perfluorohexyl chloride and perfluorohexyl bromide was observed when PFHxS was heated at temperatures between 275 and 475 °C in the presence of NaCl and NaBr, respectively. To our knowledge, this is the first report of chlorinated or brominated VOF products during thermal treatment of a PFAA. These findings suggest that a range of mixed halogenated VOF may form during thermal treatment of PFAS at relatively low temperature (e.g., 500 °C) and that these can be a function of salts present in the matrix.
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Ácidos Alcanossulfônicos , Fluorocarbonos , Humanos , Cloreto de Sódio , Temperatura , AlcanossulfonatosRESUMO
This multicenter retrospective study compared the performance of radiomics analysis coupled with machine learning (ML) with that of radiologists for the classification of breast tumors. A total of 93 consecutive women (mean age: 49 ± 12 years) with 104 histopathologically verified enhancing lesions (mean size: 22.8 ± 15.1 mm), classified as suspicious on multiparametric breast MRIs were included. Two experienced breast radiologists assessed all of the lesions, assigning a Breast Imaging Reporting and Database System (BI-RADS) suspicion category, providing a diffusion-weighted imaging (DWI) score based on lesion signal intensity, and determining the apparent diffusion coefficient (ADC). Ten predictive models for breast lesion discrimination were generated using radiomic features extracted from the multiparametric MRI. The area under the receiver operating curve (AUC) and the accuracy were compared using McNemar's test. Multiparametric radiomics with DWI score and BI-RADS (accuracy = 88.5%; AUC = 0.93) and multiparametric radiomics with ADC values and BI-RADS (accuracy= 88.5%; AUC = 0.96) models showed significant improvements in diagnostic accuracy compared to the multiparametric radiomics (DWI + DCE data) model (p = 0.01 and p = 0.02, respectively), but performed similarly compared to the multiparametric assessment by radiologists (accuracy = 85.6%; AUC = 0.03; p = 0.39). In conclusion, radiomics analysis coupled with the ML of multiparametric MRI could assist in breast lesion discrimination, especially for less experienced readers of breast MRIs.
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The aim of this study was to determine the range of apparent diffusion coefficient (ADC) values for benign axillary lymph nodes in contrast to malignant axillary lymph nodes, and to define the optimal ADC thresholds for three different ADC parameters (minimum, maximum, and mean ADC) in differentiating between benign and malignant lymph nodes. This retrospective study included consecutive patients who underwent breast MRI from January 2017-December 2020. Two-year follow-up breast imaging or histopathology served as the reference standard for axillary lymph node status. Area under the receiver operating characteristic curve (AUC) values for minimum, maximum, and mean ADC (min ADC, max ADC, and mean ADC) for benign vs malignant axillary lymph nodes were determined using the Wilcoxon rank sum test, and optimal ADC thresholds were determined using Youden's Index. The final study sample consisted of 217 patients (100% female, median age of 52 years (range, 22-81), 110 with benign axillary lymph nodes and 107 with malignant axillary lymph nodes. For benign axillary lymph nodes, ADC values (×10-3 mm2/s) ranged from 0.522-2.712 for mean ADC, 0.774-3.382 for max ADC, and 0.071-2.409 for min ADC; for malignant axillary lymph nodes, ADC values (×10-3 mm2/s) ranged from 0.796-1.080 for mean ADC, 1.168-1.592 for max ADC, and 0.351-0.688 for min ADC for malignant axillary lymph nodes. While there was a statistically difference in all ADC parameters (p<0.001) between benign and malignant axillary lymph nodes, boxplots illustrate overlaps in ADC values, with the least overlap occurring with mean ADC, suggesting that this is the most useful ADC parameter for differentiating between benign and malignant axillary lymph nodes. The mean ADC threshold that resulted in the highest diagnostic accuracy for differentiating between benign and malignant lymph nodes was 1.004×10-3 mm2/s, yielding an accuracy of 75%, sensitivity of 71%, specificity of 79%, positive predictive value of 77%, and negative predictive value of 74%. This mean ADC threshold is lower than the European Society of Breast Imaging (EUSOBI) mean ADC threshold of 1.300×10-3 mm2/s, therefore suggesting that the EUSOBI threshold which was recently recommended for breast tumors should not be extrapolated to evaluate the axillary lymph nodes.
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BACKGROUND: Nearly 1 in 5 American children are obese. The primary purpose of this study is to evaluate the relationship between childhood obesity and perioperative complications, patient-reported outcomes (PRO), and functional recovery after closed reduction and percutaneous pinning (CRPP) of type II and III supracondylar humerus fractures. METHODS: Retrospective review of patients treated operatively with CRPP of Wilkins modification of the Gartland classification type II and III supracondylar humerus fractures was performed over a 1-year timeframe (July 1, 2016 to July 1, 2017). One hundred forty-four patients under the age of 16 treated were identified. Obesity was defined as body mass index (BMI) at or above the 95th percentile for age. Obesity as a risk factor for poor outcomes was assessed. The primary outcome measure was postoperative PRO [quick-DASH, Patient Reported Outcomes Measurement Information System (PROMIS)-UE, PROMIS Global Health, and PROMIS Pain scores]. RESULTS: Mean age at surgery was 5.9 years (SD=2.1, 1.07 to 12.2) and mean age at final follow-up (3.3 y) was 8.8 (SD=2.14, 4 to 16). Mean patient BMI was 17.2 (SD=4.48, 12.4 to 56.2). Sixty-six patients were female (45.8%) and 78 patients were male (54.2%). In all, 31 of 144 patients (21.5%) met criteria for obesity. Obesity (95th percentile for BMI or above) was not associated with a higher rate of complications overall (χ2=1.29, P=0.256), range of motion loss (χ2=0.2, P=0.655) or requirement of postoperative physical therapy (χ2=0.17, P=0.678). Seventy-five patients were available and willing to participate in the outcomes score assessments. Mean follow-up for this cohort of 75 patients was 3.3 years (SD=0.31, 2.85 to 3.88). There were no differences in PROMIS pain, PROMIS upper extremity function, PROMIS general health, or quick-DASH scores when comparing obese with nonobese patients. CONCLUSIONS: Obesity is a growing concern in the United States and its effect on long-term outcomes after CRPP of supracondylar humerus fractures is unknown. The present study demonstrates no difference in complications or PRO among obese patients compared with nonobese patients. LEVEL OF EVIDENCE: Level IV-retrospective cohort study.
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Redução Fechada , Fixação Interna de Fraturas , Fraturas do Úmero/cirurgia , Obesidade/complicações , Medidas de Resultados Relatados pelo Paciente , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Redução Fechada/efeitos adversos , Articulação do Cotovelo/fisiopatologia , Feminino , Seguimentos , Fixação Interna de Fraturas/efeitos adversos , Humanos , Lactente , Masculino , Modalidades de Fisioterapia , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Invasive cervical resorption is entirely uncommon entities and the etiology is poorly understood. A 19 year old patient presented with fractured upper left central incisor and sinus tract opening on the distobuccal aspect in cervical region. Radiographic examination shows irregular radiolucency over the coronal one-third and it extended externally towards the external invasive resorption. After sectional obturation, the defect was accessed surgically. The resorption area was chemomechanically debrided using irrigant solution. Fibre post placement using flowable composite resin and Mineral Trioxide Aggregate (MTA) was used to fill the resorptive defect, and the coronal access was temporarily sealed. Composite restoration was subsequently replaced with ceramic crown after 4 years. Radiographs at 1 and 4 years showed adequate repair of the resorption and endodontic success. Clinically and radiographically the tooth was asymptomatic, and no periodontal pocket was found after a 4-year followup.
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BACKGROUND AND AIM: Ulcerative colitis (UC) and Crohn's disease (CD) are two major phenotypes of inflammatory bowel disease (IBD) that present with inflammation of the colon or the entire gastrointestinal tract, respectively. Genome-wide association studies have confirmed the role of nucleotide-binding oligomerization domain protein-2 (NOD2) variants and identified several other genes associated with IBD. We investigated whether variants in NOD2 and interleukin-23 receptor (IL23R) are associated with IBD in a well-characterized case-control cohort from southern India. METHODS: We recruited 652 patients (411 UC and 241 CD) using established diagnostic criteria and 442 age-, sex-, and ethnically-matched, normal individuals. By direct sequencing, we screened the complete NOD2 gene and genotyped the R381Q variant in IL23R, and performed an association analysis and genotype-phenotype correlation analysis. RESULTS: The clinical presentation of UC and CD patients did not differ significantly from the Europeans. We observed a monomorphic status for three common disease-susceptible variants, R702W, G908R, and 1007fs in NOD2; three other single nucleotide polymorphisms, P268S, R459R, and R587R, had a comparable minor allele frequency in patients and controls. Compared to Europeans, we found a low frequency (â¼1%) of the protective allele at R381Q in IL23R and no statistically-significant association with IBD (odds ratio = 0.87; 95% confidence interval = 0.26-2.86; P>0.05). CONCLUSIONS: Our study suggests that variants in the NOD2 gene and the protective variant R381Q in IL23R are not associated with IBD in Indians. Additional variants in these or other candidate genes might play a major role in the pathophysiology of IBD in Indians.
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Povo Asiático/genética , Colite Ulcerativa/genética , Doença de Crohn/genética , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina/genética , População Branca/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Colite Ulcerativa/etnologia , Doença de Crohn/etnologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Índia/epidemiologia , Lactente , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fenótipo , Medição de Risco , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare multi-organ cancer syndrome and understanding its genetic basis may help comprehend the molecular mechanism of familial cancer. A number of germ line mutations in the STK11 gene, encoding a serine threonine kinase have been reported in these patients. However, STK11 mutations do not explain all PJS cases. An earlier study reported absence of STK11 mutations in two Indian families and suggested another potential locus on 19q13.4 in one of them. METHODS: We sequenced the promoter and the coding region including the splice-site junctions of the STK11 gene in 16 affected members from ten well-characterized Indian PJS families with a positive family history. RESULTS: We did not observe any of the reported mutations in the STK11 gene in the index patients from these families. We identified a novel pathogenic mutation (c.790_793 delTTTG) in the STK11 gene in one index patient (10%) and three members of his family. The mutation resulted in a frame-shift leading to premature termination of the STK11 protein at 286th codon, disruption of kinase domain and complete loss of C-terminal regulatory domain. Based on these results, we could offer predictive genetic testing, prenatal diagnosis and genetic counselling to other members of the family. CONCLUSION: Ours is the first study reporting the presence of STK11 mutation in Indian PJS patients. It also suggests that reported mutations in the STK11 gene are not responsible for the disease and novel mutations also do not account for many Indian PJS patients. Large-scale genomic deletions in the STK11 gene or another locus may be associated with the PJS phenotype in India and are worth future investigation.