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1.
Nat Chem Biol ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965384

RESUMO

Targeted protein degradation (TPD) is an emerging therapeutic strategy that would benefit from new chemical entities with which to recruit a wider variety of ubiquitin E3 ligases to target proteins for proteasomal degradation. Here we describe a TPD strategy involving the recruitment of FBXO22 to induce degradation of the histone methyltransferase and oncogene NSD2. UNC8732 facilitates FBXO22-mediated degradation of NSD2 in acute lymphoblastic leukemia cells harboring the NSD2 gain-of-function mutation p.E1099K, resulting in growth suppression, apoptosis and reversal of drug resistance. The primary amine of UNC8732 is metabolized to an aldehyde species, which engages C326 of FBXO22 to recruit the SCFFBXO22 Cullin complex. We further demonstrate that a previously reported alkyl amine-containing degrader targeting XIAP is similarly dependent on SCFFBXO22. Overall, we present a potent NSD2 degrader for the exploration of NSD2 disease phenotypes and a new FBXO22-recruitment strategy for TPD.

2.
J Biol Chem ; 297(5): 101249, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34592312

RESUMO

Caspases are a family of cysteinyl proteases that control programmed cell death and maintain homeostasis in multicellular organisms. The caspase family is an excellent model to study protein evolution because all caspases are produced as zymogens (procaspases [PCPs]) that must be activated to gain full activity; the protein structures are conserved through hundreds of millions of years of evolution; and some allosteric features arose with the early ancestor, whereas others are more recent evolutionary events. The apoptotic caspases evolved from a common ancestor (CA) into two distinct subfamilies: monomers (initiator caspases) or dimers (effector caspases). Differences in activation mechanisms of the two subfamilies, and their oligomeric forms, play a central role in the regulation of apoptosis. Here, we examine changes in the folding landscape by characterizing human effector caspases and their CA. The results show that the effector caspases unfold by a minimum three-state equilibrium model at pH 7.5, where the native dimer is in equilibrium with a partially folded monomeric (PCP-7, CA) or dimeric (PCP-6) intermediate. In comparison, the unfolding pathway of PCP-3 contains both oligomeric forms of the intermediate. Overall, the data show that the folding landscape was first established with the CA and was retained for >650 million years. Partially folded monomeric or dimeric intermediates in the ancestral ensemble provide mechanisms for evolutionary changes that affect stability of extant caspases. The conserved folding landscape allows for the fine-tuning of enzyme stability in a species-dependent manner while retaining the overall caspase-hemoglobinase fold.


Assuntos
Caspases Efetoras/química , Evolução Molecular , Modelos Moleculares , Dobramento de Proteína , Multimerização Proteica , Caspases Efetoras/genética , Caspases Efetoras/metabolismo , Humanos
3.
J Pathol ; 255(4): 362-373, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34370295

RESUMO

Urinary fatty acid binding protein 1 (FABP1, also known as liver-type FABP) has been implicated as a biomarker of acute kidney injury (AKI) in humans. However, the precise biological mechanisms underlying its elevation remain elusive. Here, we show that urinary FABP1 primarily reflects impaired protein reabsorption in proximal tubule epithelial cells (PTECs). Bilateral nephrectomy resulted in a marked increase in serum FABP1 levels, suggesting that the kidney is an essential organ for removing serum FABP1. Injected recombinant FABP1 was filtered through the glomeruli and robustly reabsorbed via the apical membrane of PTECs. Urinary FABP1 was significantly elevated in mice devoid of megalin, a giant endocytic receptor for protein reabsorption. Elevation of urinary FABP1 was also observed in patients with Dent disease, a rare genetic disease characterized by defective megalin function in PTECs. Urinary FABP1 levels were exponentially increased following acetaminophen overdose, with both nephrotoxicity and hepatotoxicity observed. FABP1-deficient mice with liver-specific overexpression of FABP1 showed a massive increase in urinary FABP1 levels upon acetaminophen injection, indicating that urinary FABP1 is liver-derived. Lastly, we employed transgenic mice expressing diphtheria toxin receptor (DT-R) either in a hepatocyte- or in a PTEC-specific manner, or both. Upon administration of diphtheria toxin (DT), massive excretion of urinary FABP1 was induced in mice with both kidney and liver injury, while mice with either injury type showed marginal excretion. Collectively, our data demonstrated that intact PTECs have a considerable capacity to reabsorb liver-derived FABP1 through a megalin-mediated mechanism. Thus, urinary FABP1, which is synergistically enhanced by concurrent liver injury, is a biomarker for impaired protein reabsorption in AKI. These findings address the use of urinary FABP1 as a biomarker of histologically injured PTECs that secrete FABP1 into primary urine, and suggest the use of this biomarker to simultaneously monitor impaired tubular reabsorption and liver function. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Injúria Renal Aguda , Biomarcadores/urina , Proteínas de Ligação a Ácido Graxo/urina , Hepatopatias , Animais , Humanos , Camundongos
4.
J Biol Chem ; 295(43): 14578-14591, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-32788218

RESUMO

Coral reefs are experiencing precipitous declines around the globe with coral diseases and temperature-induced bleaching being primary drivers of these declines. Regulation of apoptotic cell death is an important component in the coral stress response. Although cnidaria are known to contain complex apoptotic signaling pathways, similar to those in vertebrates, the mechanisms leading to cell death are largely unexplored. We identified and characterized two caspases each from Orbicella faveolata, a disease-sensitive reef-building coral, and Porites astreoides, a disease-resistant reef-building coral. The caspases are predicted homologs of the human executioner caspases-3 and -7, but OfCasp3a (Orbicella faveolata caspase-3a) and PaCasp7a (Porites astreoides caspase-7a), which we show to be DXXDases, contain an N-terminal caspase activation/recruitment domain (CARD) similar to human initiator/inflammatory caspases. OfCasp3b (Orbicella faveolata caspase-3b) and PaCasp3 (Porites astreoides caspase-3), which we show to be VXXDases, have short pro-domains, like human executioner caspases. Our biochemical analyses suggest a mechanism in coral which differs from that of humans, where the CARD-containing DXXDase is activated on death platforms but the protease does not directly activate the VXXDase. The first X-ray crystal structure of a coral caspase, of PaCasp7a determined at 1.57 Å resolution, reveals a conserved fold and an N-terminal peptide bound near the active site that may serve as a regulatory exosite. The binding pocket has been observed in initiator caspases of other species. These results suggest mechanisms for the evolution of substrate selection while maintaining common activation mechanisms of CARD-mediated dimerization.


Assuntos
Antozoários/enzimologia , Caspases/metabolismo , Sequência de Aminoácidos , Animais , Antozoários/química , Antozoários/citologia , Antozoários/metabolismo , Apoptose , Caspases/química , Recifes de Corais , Cristalografia por Raios X , Ativação Enzimática , Humanos , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Alinhamento de Sequência , Especificidade por Substrato
5.
Eur J Nucl Med Mol Imaging ; 47(5): 1220-1227, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31758225

RESUMO

PURPOSE: Prognostic significance of volumetric 18F-fluorodeoxyglucose (FDG) positron emission tomography/computer tomography (PET/CT) parameters in carbon-ion radiotherapy (C-ion RT) treated stage I non-small cell lung cancer, and need of histology-wise separate cut-off values for risk stratification were assessed. METHODS: Thirty-nine patients (29 men and 10 women, 71.9 ± 8.3 years) who underwent FDG PET/CT examinations before C-ion RT were retrospectively evaluated. FDG-PET parameters: standardized uptake values (SUVmax, SUVpeak, and SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), and clinicopathological variables were assessed for prognosis using Cox proportional hazards regression analysis. Mann-Whitney test compared medians of significant parameters between adenocarcinoma (AC) and squamous cell carcinoma (SCC), and Kaplan-Meier curves were plotted for median-based low- and high-risk groups. RESULTS: Median follow-up period was 44.8 months. 1/2/3-year overall survival (OS), progression-free survival (PFS) and local control (LC) rates were 94.9/84.3/70.8, 82.1/69.2/58.4 and 97.3/85.7/82.3%. Multivariate analysis revealed age (hazard ratio, HR: 1.09; 95% confidence interval, CI: 1.0-1.19, p < 0.05) and MTV (HR 4.83, 95% CI 1.21-19.27, p < 0.03) predicted OS, and only MTV predicted PFS (HR 5.3, CI 1.32-21.35, p < 0.02) independently. Compared with AC, SCC had higher MTV (median, 6.625cm3 vs 0.2 cm3, p < 0.01). Single MTV cut-off based on overall cohort was insignificant in SCC for PFS (p > 0.02); separate cut-offs of MTV, 0.2 cm3 for AC (p < 0.03) and 6.625 cm3 for SCC (p < 0.05) were relevant. CONCLUSION: Among all FDG PET/CT parameters, only MTV beared prognostic ability for stage I NSCLC treated with C-ion RT, and its histological variation may need consideration for risk-adapted therapeutic management.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carbono , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Prognóstico , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Carga Tumoral
6.
Biochem J ; 476(22): 3475-3492, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31675069

RESUMO

Apoptotic caspases evolved with metazoans more than 950 million years ago (MYA), and a series of gene duplications resulted in two subfamilies consisting of initiator and effector caspases. The effector caspase genes (caspases-3, -6, and -7) were subsequently fixed into the Chordata phylum more than 650 MYA when the gene for a common ancestor (CA) duplicated, and the three effector caspases have persisted throughout mammalian evolution. All caspases prefer an aspartate residue at the P1 position of substrates, so each caspase evolved discrete cellular roles through changes in substrate recognition at the P4 position combined with allosteric regulation. We examined the evolution of substrate specificity in caspase-6, which prefers valine at the P4 residue, compared with caspases-3 and -7, which prefer aspartate, by reconstructing the CA of effector caspases (AncCP-Ef1) and the CA of caspase-6 (AncCP-6An). We show that AncCP-Ef1 is a promiscuous enzyme with little distinction between Asp, Val, or Leu at P4. The specificity of caspase-6 was defined early in its evolution, where AncCP-6An demonstrates a preference for Val over Asp at P4. Structures of AncCP-Ef1 and of AncCP-6An show a network of charged amino acids near the S4 pocket that, when combined with repositioning a flexible active site loop, resulted in a more hydrophobic binding pocket in AncCP-6An. The ancestral protein reconstructions show that the caspase-hemoglobinase fold has been conserved for over 650 million years and that only three substitutions in the scaffold are necessary to shift substrate selection toward Val over Asp.


Assuntos
Caspases Efetoras/química , Evolução Molecular , Mamíferos/genética , Animais , Caspases Efetoras/genética , Caspases Efetoras/metabolismo , Humanos , Mamíferos/classificação , Filogenia , Conformação Proteica , Especificidade por Substrato
7.
Eur J Orthop Surg Traumatol ; 24(6): 993-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24253959

RESUMO

BACKGROUND: Proximal tibia fractures are difficult to treat especially when soft tissues are compromised by conventional open reduction and internal fixation with high complication rates. Many methods have been tried to manage these fractures. Less invasive stabilization system (LISS) is the latest technology applied for these injuries. This report presents clinical results of the LISS for the treatment of complex proximal tibia fractures. MATERIALS AND METHODS: From June 2007 to May 2010, total of 35 cases of the proximal tibia fractures (19 AO type 41A, 11 type 41B and five AO type 41C) were treated with the LISS technique. Clinical and radiological evaluation was done at 6, 10, 14, 20, 24 weeks and 9, 12, 18 and 24 months, respectively. RESULTS: The mean age of the patients was 50.17 years (range 20-73 years); male patients were 21 and female 14. The mean follow-up time was 31.42 months (range 21-42 months). The patients were evaluated using Knee Society scores, and the mean score was 92.11 (range 84-100); the mean full weight bearing time was 15.8 weeks (range 12-22), and union time was 25.17 weeks (range 20-29). Superficial infections and slight mal-alignment were seen on five patients each. CONCLUSION: The less invasive stabilization internal fixator system can be used successfully to treat complex proximal tibia fractures with minimal complications. It can be an alternative method for the treatment of the proximal tibia fractures.


Assuntos
Fixação Interna de Fraturas/instrumentação , Fixadores Internos , Fraturas da Tíbia/cirurgia , Adulto , Idoso , Articulação do Tornozelo/fisiopatologia , Feminino , Seguimentos , Fixação Interna de Fraturas/efeitos adversos , Consolidação da Fratura , Humanos , Fixadores Internos/efeitos adversos , Articulação do Joelho/fisiopatologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular , Fraturas da Tíbia/diagnóstico por imagem , Fatores de Tempo , Suporte de Carga , Adulto Jovem
8.
Environ Eng Sci ; 30(2): 89-96, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23443733

RESUMO

Estrogens, a potent group of endocrine disruptors toward aquatic species, are primarily excreted as conjugates from humans and animals. Radioassay-based approaches with detailed speciation have been frequently conducted for environmental-fate studies for pesticides; however, such techniques have not been exploited for reproductive hormones, and especially for hormone conjugates. This article describes a simple, robust, and high-mass-recovery approach to investigate the fate and transformation of a prototype estrogen conjugate, that is, 17ß-estradiol-3-glucuronide (E2-3G), and its metabolites (free estrogens) in a laboratory soil and water matrix without the need for enzymatic cleavage and/or fluorescent derivatization. E2-3G and its metabolites were baseline resolved in a single run using high-performance liquid chromatography (HPLC) and quantified by liquid scintillation counting of the HPLC effluents. Transformation of E2-3G and the disposition of its metabolites--the free estrogens 17ß-estradiol and estrone--into aqueous, sorbed, and gaseous phases, were adequately accounted for in a soil-water batch system. High mass balances ranging from 99.0% to 114.1% were obtained. Although the method gave lower sensitivity (parts per billion) than tandem mass spectrometer (parts per trillion), it offered sufficient chromatographic resolution and sensitivity to study the fate of labile estrogens in environmental matrices, using the concentration range of this study. An additional advantage of the approach was the relatively low cost of the instrumentation employed. The presented approach can be successfully applied to study the fate of conjugated hormones and their metabolites in the environment allowing simultaneous discernment of complex fate and transformation processes in soil, water, and gas.

9.
Environ Sci Pollut Res Int ; 30(43): 98452-98469, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37608180

RESUMO

The study was carried out in the Khandbari Municipality, Sankhuwasabha District, Eastern Nepal to document the spring location and assess the water quality of the spring water for drinking and irrigation purposes. A total of 85 springs were mapped, which are located from 274 to 2176 m in altitude. Spring water samples were collected from 33 springs in the pre-monsoon (November, 2021) and 31 springs in the post-monsoon (March, 2022). Correlation matrices, t-test, principal component analysis (PCA), Piper diagram, Gibbs diagram, water quality index (WQI), United States Salinity Laboratory (USSL) diagram, and Wilcox diagram were applied for evaluating the spring water. All the physicochemical parameters were within the Nepalese National Drinking Water Quality Standard (NDWQS) and drinking water quality guidelines of the World Health Organization (WHO) except for pH in the pre-monsoon and iron in the post-monsoon season. The main contributors to the groundwater are Na+, Ca2+, Cl-, total dissolved solids (TDS), and total hardness, which exhibit significant correlations with electrical conductivity (EC) similar to TDS, suggesting their common source of origin. Based on the WQI, spring water is excellent in the post-monsoon and excellent and good in the pre-monsoon season. Furthermore, the spring water is excellent for irrigation purposes except for the percent sodium in the post-monsoon and the magnesium ratio in the pre-monsoon season. Gibbs diagram illustrates that spring water is mainly governed by rock and precipitation dominance in some springs. The PCA indicates that anthropogenic activities (mixing of human waste and agricultural run-off in the spring water) are the main causes of contamination. Piper trilinear diagram demonstrates carbonate dissolution and silicate weathering as major processes for controlling the spring water chemistry. The study reveals that 62.5% of spring water was contaminated with microbes. For benthic macroinvertebrates, 18 springs were sampled, where nine orders and 17 families were recorded in the pre-monsoon and six orders and ten families in the post-monsoon season. The main influencing variables for macroinvertebrate assemblages are elevation, discharge, NO3-, and NH3.


Assuntos
Água Potável , Humanos , Nepal , Qualidade da Água , Agricultura , Altitude
10.
J Clin Oncol ; 41(22): 3826-3838, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307512

RESUMO

PURPOSE: Radiation-associated cardiac disease is a major cause of morbidity/mortality among childhood cancer survivors. Radiation dose-response relationships for cardiac substructures and cardiac diseases remain unestablished. METHODS: Using the 25,481 5-year survivors of childhood cancer treated from 1970 to 1999 in the Childhood Cancer Survivor Study, we evaluated coronary artery disease (CAD), heart failure (HF), valvular disease (VD), and arrhythmia. We reconstructed radiation doses for each survivor to the coronary arteries, chambers, valves, and whole heart. Excess relative rate (ERR) models and piecewise exponential models evaluated dose-response relationships. RESULTS: The cumulative incidence 35 years from diagnosis was 3.9% (95% CI, 3.4 to 4.3) for CAD, 3.8% (95% CI, 3.4 to 4.2) for HF, 1.2% (95% CI, 1.0 to 1.5) for VD, and 1.4% (95% CI, 1.1 to 1.6) for arrhythmia. A total of 12,288 survivors (48.2%) were exposed to radiotherapy. Quadratic ERR models improved fit compared with linear ERR models for the dose-response relationship between mean whole heart and CAD, HF, and arrhythmia, suggesting a potential threshold dose; however, such departure from linearity was not observed for most cardiac substructure end point dose-response relationships. Mean doses of 5-9.9 Gy to the whole heart did not increase the risk of any cardiac diseases. Mean doses of 5-9.9 Gy to the right coronary artery (rate ratio [RR], 2.6 [95% CI, 1.6 to 4.1]) and left ventricle (RR, 2.2 [95% CI, 1.3 to 3.7]) increased risk of CAD, and to the tricuspid valve (RR, 5.5 [95% CI, 2.0 to 15.1]) and right ventricle (RR, 8.4 [95% CI, 3.7 to 19.0]) increased risk of VD. CONCLUSION: Among children with cancer, there may be no threshold dose below which radiation to the cardiac substructures does not increase the risk of cardiac diseases. This emphasizes their importance in modern treatment planning.


Assuntos
Sobreviventes de Câncer , Cardiopatias , Insuficiência Cardíaca , Neoplasias , Lesões por Radiação , Criança , Humanos , Neoplasias/tratamento farmacológico , Sobreviventes , Cardiopatias/etiologia , Cardiopatias/complicações , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Relação Dose-Resposta à Radiação
11.
Artigo em Inglês | MEDLINE | ID: mdl-37061912

RESUMO

PURPOSE: Radiation therapy (RT) is an essential component in the treatment of many pediatric malignancies. Thoracic RT may expose the heart to radiation dose and thereby increase the risk of late cardiac disease. This comprehensive review from the Pediatric Normal Tissue Effects in the Clinic (PENTEC) initiative focused on late cardiac disease in survivors of childhood cancer treated with RT. METHODS AND MATERIALS: This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. We identified 1496 articles; 4 were included for dose-response modeling between mean cardiac radiation dose and risk of late coronary artery disease, heart failure (HF), valvular disease, and any cardiac disease. RESULTS: For each 10-Gy increase in corrected mean cardiac radiation dose in 1.8- to 2.0-Gy fractions, we estimated a hazard ratio of 2.01 (95% confidence interval [CI], 1.79-2.25) for coronary artery disease, of 1.87 (95% CI, 1.70-2.06) for HF, of 1.87 (95% CI, 1.78-1.96) for valvular disease, and of 1.88 (95% CI, 1.75-2.03) for any cardiac disease. From the same model, for each 100-mg/m2 increase in cumulative anthracycline dose, the hazard ratio for the development of HF was 1.93 (95% CI, 1.58-2.36), equivalent to an increase in mean heart dose of approximately 10.5 Gy. Other nontreatment factors were inconsistently reported in the analyzed articles. CONCLUSIONS: Radiation dose to the heart increases the risk of late cardiac disease, but survivors of childhood cancer who receive a mean dose <10 Gy at standard fractionation are at low absolute risk (<∼2% approximately 30 years after exposure) of late cardiac disease in the absence of anthracycline exposure. Minimizing cardiac radiation dose is especially relevant in children receiving anthracyclines. When cardiac sparing is not possible, we recommend prioritizing target coverage. It is likely that individual cardiac substructure doses will be a better predictor of specific cardiac diseases than mean dose, and we urge the pediatric oncology community to further study these relationships.

12.
bioRxiv ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37961297

RESUMO

Targeted protein degradation (TPD) is an emerging therapeutic strategy that would benefit from new chemical entities with which to recruit a wider variety of ubiquitin E3 ligases to target proteins for proteasomal degradation. Here, we describe a TPD strategy involving the recruitment of FBXO22 to induce degradation of the histone methyltransferase and oncogene NSD2. UNC8732 facilitates FBXO22-mediated degradation of NSD2 in acute lymphoblastic leukemia cells harboring the NSD2 gain of function mutation p.E1099K, resulting in growth suppression, apoptosis, and reversal of drug resistance. The primary amine of UNC8732 is metabolized to an aldehyde species, which engages C326 of FBXO22 in a covalent and reversible manner to recruit the SCF FBXO22 Cullin complex. We further demonstrate that a previously reported alkyl amine-containing degrader targeting XIAP is similarly dependent on SCF FBXO22 . Overall, we present a highly potent NSD2 degrader for the exploration of NSD2 disease phenotypes and a novel FBXO22-dependent TPD strategy.

13.
Environ Sci Technol ; 46(20): 11047-53, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-22967238

RESUMO

In the environment, conjugated estrogens are nontoxic but may hydrolyze to their potent unconjugated, 'free' forms. Compared to free estrogens, conjugated estrogens would be more mobile in the environment because of their higher water solubility. To identify the fate of a conjugated estrogen in natural agricultural soils, batch experiments were conducted with a (14)C labeled prototype conjugate, 17ß-estradiol-3-glucuronide (E2-3G). Initially, aqueous dissipation was dominated by biological hydrolysis of E2-3G and its oxidized metabolite, estrone glucuronide (E1-3G), both of which were transformed into the free estrogens, 17ß-estradiol (E2) and estrone (E1), respectively. Following hydrolysis, hydrophobic sorption interactions of E2 and E1 dominated. Depending on soil organic matter contents, dissolved E2-3G persisted from 1-14 d, which was much longer than what others reported for free estrogens (generally <24 h). Biodegradation rate constants of E2-3G were smaller in the subsoil (0.01-0.02 h(-1)) compared to topsoil (0.2-0.4 h(-1)). Field observations supported our laboratory findings where significant concentrations (425 ng L(-1)) of intact E2-3G were detected in groundwater (6.5-8.1 m deep) near a swine (Sus scrofa domesticus) farm. This study provides evidence that conjugate estrogens may be a significant source of free estrogens to surface water and groundwater.


Assuntos
Agricultura , Estrogênios Conjugados (USP)/análise , Poluentes do Solo/análise , Solo/química , Biodegradação Ambiental , Monitoramento Ambiental , Estradiol/análogos & derivados , Estradiol/análise , Estrogênios/análise , Estrona/análise , Água Subterrânea , Modelos Químicos , Poluentes Químicos da Água/análise
14.
Phys Med Biol ; 67(12)2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35613603

RESUMO

Objective. Patients who receive proton beam therapy are exposed to unwanted stray neutrons. Stray radiations increase the risk of late effects in normal tissues, such as second cancers and cataracts, and may cause implanted devices such as pacemakers to malfunction. Compared to therapeutic beams, little attention has been paid to modeling stray neutron exposures. In the past decade, substantial progress was made to develop semiempirical models of stray neutron dose equivalent, but models to routinely calculate neutron absorbed dose and kerma are still lacking. The objective of this work was to develop a new physics based analytical model to calculate neutron spectral fluence, kerma, and absorbed dose in a water phantom.Approach. We developed the model using dosimetric data from Monte Carlo simulations and neutron kerma coefficients from the literature. The model explicitly considers the production, divergence, scattering, and attenuation of neutrons. Neutron production was modeled for 120-250 MeV proton beams impinging on a variety of materials. Fluence, kerma and dose calculations were performed in a 30 × 180 × 44 cm3phantom at points up to 43 cm in depth and 80 cm laterally.Main Results. Predictions of the analytical model agreed reasonably with corresponding values from Monte Carlo simulations, with a mean difference in average energy deposited of 20%, average kerma coefficient of 21%, and absorbed dose to water of 49%.Significance. The analytical model is simple to implement and use, requires less configuration data that previously reported models, and is computationally fast. This model appears potentially suitable for integration in treatment planning system, which would enable risk calculations in prospective and retrospective cases, providing a powerful tool for epidemiological studies and clinical trials.


Assuntos
Terapia com Prótons , Exposição à Radiação , Humanos , Método de Monte Carlo , Nêutrons , Física , Estudos Prospectivos , Terapia com Prótons/efeitos adversos , Radiometria/métodos , Dosagem Radioterapêutica , Estudos Retrospectivos , Água
15.
JNMA J Nepal Med Assoc ; 60(246): 177-182, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35210628

RESUMO

INTRODUCTION: Pancreatoduodenectomy with vascular resection is performed in locally advanced periampullary malignancies. In our practice, early oral feeding is initiated in patients undergoing pancreatoduodenectomy. This study aims to find the prevalence of early oral feeding with vascular resection among patients undergoing pancreatoduodenectomy. METHODS: This was a descriptive cross-sectional study conducted among hospital records of 152 patients who underwent pancreatoduodenectomy in the department of surgery of a tertiary care hospital from 2016 to 2020. Ethical approval was taken from the Institutional Review Committee (Reference number: 0812202102). Convenience sampling was done. Patients clinical and sociodemographic data were collected and analyzed using Statistical Package for the Social Sciences version 20. Point estimate at 95% Confidence Interval was calculated along with frequency, percentage, mean, and median. RESULTS: Among 152 patients undergoing pancreatoduodenectomy, early oral feeding with vascular resection was done in 17 (11.18%) (6.17-16.19 at 95% Confidence Interval). Portal vein and superior mesenteric artery were resected in one (5.88%) and hepatic artery in one (5.88%) patient. Type I, III and IV reconstruction was done in nine (52.9%), five (29.41%) and one (5.88%) respectively. Clinically relevant delayed gastric emptying and postoperative pancreatic fistula were seen in two (11.7%). Complication of Clavien-Dindo Grade III or higher was seen in one (5.88%) patient. One (5.88%) mortality was noted. CONCLUSIONS: The prevalence of early oral feeding with vascular resection among patients undergoing pancreatoduodenectomy was similar to other studies done in similar settings. Early enteral feeding is well tolerated in patients undergoing pancreatoduodenectomy with vascular resection.


Assuntos
Neoplasias Pancreáticas , Pancreaticoduodenectomia , Estudos Transversais , Humanos , Neoplasias Pancreáticas/patologia , Pancreaticoduodenectomia/efeitos adversos , Veia Porta/patologia , Veia Porta/cirurgia , Centros de Atenção Terciária
16.
Rev Bras Ortop (Sao Paulo) ; 57(2): 295-300, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35652028

RESUMO

Objective To analyze the radiological, clinical, and functional outcomes of clavicle fractures treated with the minimally-invasive plate osteosynthesis (MIPO) technique. Methods From June 2018 to July 2019, 17 cases of clavicular fractures were managed using the MIPO technique under C-arm fluoroscopy. The functional outcomes were assessed using the Constant-Murley score and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. The clinical results of union, the complications, the operative time, the hospital stay, as well as infection, were analyzed. Results The mean follow-up time was of 10.41 ± 1.75 months (range: 8 to 14 months). There were 11 male and 6 female patients, with a mean age of 39.05 ± 10.76 years (range: 22 to 57 years). All fractures united on the mean time of 15.35 ± 3.08 weeks (range: 12 to 20 weeks). The mean operative time was of 98.11 ± 13.83 minutes (range: 70 to 130 minutes), and the mean length of the hospital stay was of 4.7 ± 1.12 days (range: 3 to 7 days). The mean Constant-Murley score was of 74.82 ± 6.36 in 4 th postoperstive month, and of 92.35 ± 5.48 in the 8 th postoperative month, which was statistically significant. The mean DASH score was of 9.94 ± 1.55 in the 4 th postoperative month, and of 5.29 ± 1.85 in the 8 th postoperative month, which was also statistically significant. One patient had superficial skin infection at the site of the incision. Conclusions The MIPO technique is an alternative method for the fixation of clavicle fractures, but it is technically more demanding, and requires well-equipped operating room facilities.

17.
Cureus ; 14(10): e30781, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36320800

RESUMO

Introduction The prevailing guidelines do not include the involvement of an aberrant right hepatic artery (aRHA) arising from the superior mesenteric artery in classifying borderline resectable pancreatic ductal adenocarcinoma (BR PDAC). Our novel classification aims to distinguish different entities depending on the location and degree of tumor involvement of aRHA and propose a strategy to manage tumor involvement of aRHA in PDAC. Material and methods The patients who underwent pancreaticoduodenectomy (PD) from September 1, 2018, to August 31, 2022 were analyzed retrospectively, and patients with aRHA were included in the study. Depending on the radiological data, arterial involvement of the aRHA was classified into group I with proximal involvement of the aRHA up to 2 cm from its origin in the superior mesenteric artery (SMA) and group II with distal involvement of aRHA beyond 2 cm from its origin in SMA. In addition, the resection margin status was correlated with the technique employed for managing the tumor-involved artery. Results A total of 122 patients underwent PD during the study period. Eight patients were identified to have tumor involvement of the aRHA arising from the SMA. Among the five patients in group I, three patients who had upfront surgery showed R1 resection regardless of periarterial divestment or resection/reconstruction of the involved artery, whereas R0 resection was achieved in the two patients who had neoadjuvant therapy. All patients in group II had R0 resection regardless of receiving neoadjuvant therapy. There were no significant morbidity and mortality in our series. Conclusion The aRHA should be considered in the classification of BR PDAC. Management strategies should be tailored based on the location and the degree of tumor involvement in the aRHA. We advocate neoadjuvant therapy for proximal involvement and upfront surgery for distal involvement of aRHA to achieve good oncological clearance.

18.
Biomed Phys Eng Express ; 8(2)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34874300

RESUMO

Purpose.Radiation epidemiology studies of childhood cancer survivors treated in the pre-computed tomography (CT) era reconstruct the patients' treatment fields on computational phantoms. For such studies, the phantoms are commonly scaled to age at the time of radiotherapy treatment because age is the generally available anthropometric parameter. Several reference size phantoms are used in such studies, but reference size phantoms are only available at discrete ages (e.g.: newborn, 1, 5, 10, 15, and Adult). When such phantoms are used for RT dose reconstructions, the nearest discrete-aged phantom is selected to represent a survivor of a specific age. In this work, we (1) conducted a feasibility study to scale reference size phantoms at discrete ages to various other ages, and (2) evaluated the dosimetric impact of using exact age-scaled phantoms as opposed to nearest age-matched phantoms at discrete ages.Methods.We have adopted the University of Florida/National Cancer Institute (UF/NCI) computational phantom library for our studies. For the feasibility study, eight male and female reference size UF/NCI phantoms (5, 10, 15, and 35 years) were downscaled to fourteen different ages which included next nearest available lower discrete ages (1, 5, 10 and 15 years) and the median ages at the time of RT for Wilms' tumor (3.9 years), craniospinal (8.0 years), and all survivors (9.1 years old) in the Childhood Cancer Survivor Study (CCSS) expansion cohort treated with RT. The downscaling was performed using our in-house age scaling functions (ASFs). To geometrically validate the scaling, Dice similarity coefficient (DSC), mean distance to agreement (MDA), and Euclidean distance (ED) were calculated between the scaled and ground-truth discrete-aged phantom (unscaled UF/NCI) for whole-body, brain, heart, liver, pancreas, and kidneys. Additionally, heights of the scaled phantoms were compared with ground-truth phantoms' height, and the Centers for Disease Control and Prevention (CDC) reported 50th percentile height. Scaled organ masses were compared with ground-truth organ masses. For the dosimetric assessment, one reference size phantom and seventeen body-size dependent 5-year-old phantoms (9 male and 8 female) of varying body mass indices (BMI) were downscaled to 3.9-year-old dimensions for two different radiation dose studies. For the first study, we simulated a 6 MV photon right-sided flank field RT plan on a reference size 5-year-old and 3.9-year-old (both of healthy BMI), keeping the field size the same in both cases. Percent of volume receiving dose ≥15 Gy (V15) and the mean dose were calculated for the pancreas, liver, and stomach. For the second study, the same treatment plan, but with patient anatomy-dependent field sizes, was simulated on seventeen body-size dependent 5- and 3.9-year-old phantoms with varying BMIs. V15, mean dose, and minimum dose received by 1% of the volume (D1), and by 95% of the volume (D95) were calculated for pancreas, liver, stomach, left kidney (contralateral), right kidney, right and left colons, gallbladder, thoracic vertebrae, and lumbar vertebrae. A non-parametric Wilcoxon rank-sum test was performed to determine if the dose to organs of exact age-scaled and nearest age-matched phantoms were significantly different (p < 0.05).Results.In the feasibility study, the best DSCs were obtained for the brain (median: 0.86) and whole-body (median: 0.91) while kidneys (median: 0.58) and pancreas (median: 0.32) showed poorer agreement. In the case of MDA and ED, whole-body, brain, and kidneys showed tighter distribution and lower median values as compared to other organs. For height comparison, the overall agreement was within 2.8% (3.9 cm) and 3.0% (3.2 cm) of ground-truth UF/NCI and CDC reported 50th percentile heights, respectively. For mass comparison, the maximum percent and absolute differences between the scaled and ground-truth organ masses were within 31.3% (29.8 g) and 211.8 g (16.4%), respectively (across all ages). In the first dosimetric study, absolute difference up to 6% and 1.3 Gy was found for V15and mean dose, respectively. In the second dosimetric study, V15and mean dose were significantly different (p < 0.05) for all studied organs except the fully in-beam organs. D1and D95were not significantly different for most organs (p > 0.05).Conclusion.We have successfully evaluated our ASFs by scaling UF/NCI computational phantoms from one age to another age, which demonstrates the feasibility of scaling any CT-based anatomy. We have found that dose to organs of exact age-scaled and nearest aged-matched phantoms are significantly different (p < 0.05) which indicates that using the exact age-scaled phantoms for retrospective dosimetric studies is a better approach.


Assuntos
Fótons , Radiometria , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Imagens de Fantasmas , Radiometria/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
19.
Radiother Oncol ; 176: 118-126, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36063983

RESUMO

PURPOSE: The purposes of this study were to develop and integrate a colorectal model that incorporates anatomical variations of pediatric patients into the age-scalable MD Anderson Late Effects (MDA-LE) computational phantom, and validate the model for pediatric radiation therapy (RT) dose reconstructions. METHODS: Colorectal contours were manually derived from whole-body non-contrast computed tomography (CT) scans of 114 pediatric patients (age range: 2.1-21.6 years, 74 males, 40 females). One contour was used for an anatomical template, 103 for training and 10 for testing. Training contours were used to create a colorectal principal component analysis (PCA)-based statistical shape model (SSM) to extract the population's dominant deformations. The SSM was integrated into the MDA-LE phantom. Geometric accuracy was assessed between patient-specific and SSM contours using several overlap metrics. Two alternative colorectal shapes were generated using the first 17 dominant modes of the PCA-based SSM. Dosimetric accuracy was assessed by comparing colorectal doses from test patients' CT-based RT plans (ground truth) with reconstructed doses for the mean and two alternative models in age-matched MDA-LE phantoms. RESULTS: When using all 103 PCA modes, the mean (min-max) Dice similarity coefficient, distance-to-agreement and Hausdorff distance between the patient-specific and reconstructed contours for the test patients were 0.89 (0.85-0.91), 2.1 mm (1.7-3.0), and 8.6 mm (5.7-14.3), respectively. The average percent difference between reconstructed and ground truth mean and maximum colorectal doses for the mean (alternative 1, 2) model were 6.3% (8.1%, 6.1%) and 4.4% (4.3%, 4.7%), respectively. CONCLUSIONS: We developed, validated and integrated a colorectal PCA-based SSM into the MDA-LE phantom and demonstrated its dosimetric performance for accurate pediatric RT dose reconstruction.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância , Sobreviventes de Câncer , Neoplasias Colorretais , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/radioterapia , Imagens de Fantasmas , Radiometria/métodos , Tomografia Computadorizada por Raios X/métodos
20.
Int J Surg Case Rep ; 88: 106543, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34749175

RESUMO

INTRODUCTION AND IMPORTANCE: Self-inflicted abdominal stab injury with an intention of self-harm is uncommon. Moreover, self-inflicted injury leading to avulsion of the colon has rarely been reported in the literature. We report a case of a 42-years-female with schizoaffective disorder who presented with self-inflicted stab injury on the abdomen resulting in abdominal evisceration. PRESENTATION OF CASE: A 42-years-female with schizoaffective disorder (F25) for 10 years presented to the emergency department with multiple, self-inflicted injuries on the abdomen. A large free portion of the omentum and segment of the bowel were brought in a plastic carry bag. Examination revealed multiple transverse hesitation cuts in the epigastrium and a single deep penetrating transverse cut resulting in the evisceration of the omentum and colon. Intra-operatively, avulsion of a large portion of the greater omentum and missing segment of the mid transverse colon was observed. The patient underwent an immediate abdominal exploration and side-to-side colo-colic anastomosis along with diversion ileostomy. At three months following primary surgery, ileostomy closure was done. CONCLUSION: Patients with schizophrenia spectrum psychosis are at risk of self-harm and in our case a schizoaffective patient presented with self-inflicted injuries that required an emergency abdominal exploration and repair. This case highlights a multi-disciplinary approach for the management of these cases and mandates clinicians and caregivers to be more vigilant to restrict injuries in the future.

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