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1.
Radiographics ; 43(3): e220092, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36729948

RESUMO

Zoonotic infections, which are transmitted from animals to humans, have been a substantial source of human disease since antiquity. As the human population continues to grow and human influence on the planet expands, humans frequently encounter both domestic and wild animals. This has only increased as deforestation, urbanization, agriculture, habitat fragmentation, outdoor recreation, and international travel evolve in modern society, all of which have resulted in the emergence and reemergence of zoonotic infections. Zoonotic infections pose a diagnostic challenge because of their nonspecific clinical manifestations and the need for specialized testing procedures to confirm these diagnoses. Affected patients often undergo imaging during their evaluation, and a radiologist familiar with the specific and often subtle imaging patterns of these infections can add important clinical value. The authors review the multimodality thoracic, abdominal, and musculoskeletal imaging findings of zoonotic bacterial (eg, Bartonella henselae, Pasteurella multocida, Francisella tularensis, Coxiella burnetii, and Brucella species), spirochetal (eg, Leptospira species), and parasitic (eg, Echinococcus, Paragonimus, Toxocara, and Dirofilaria species) infections that are among the more commonly encountered zoonoses in the United States. Relevant clinical, epidemiologic, and pathophysiologic clues such as exposure history, occupational risk factors, and organism life cycles are also reviewed. Although many of the imaging findings of zoonotic infections overlap with those of nonzoonotic infections, granulomatous diseases, and malignancies, radiologists' familiarity with the imaging patterns can aid in the differential diagnosis in a patient with a suspected or unsuspected zoonotic infection. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.


Assuntos
Zoonoses , Animais , Humanos , Estados Unidos , Zoonoses/diagnóstico por imagem , Zoonoses/epidemiologia , Zoonoses/microbiologia , Fatores de Risco
2.
Radiographics ; 42(2): 359-378, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35089819

RESUMO

Chest wall lesions are relatively uncommon and may be challenging once they are encountered on images. Radiologists may detect these lesions incidentally at examinations performed for other indications, or they may be asked specifically to evaluate a suspicious lesion. While many chest wall lesions have characteristic imaging findings that can result in an accurate diagnosis with use of imaging alone, other entities are difficult to distinguish at imaging because there is significant overlap among them. The interpreting radiologist should be familiar with the imaging features of both "do not touch" benign entities (which can be confidently diagnosed with imaging only, with no need for biopsy or resection unless the patient is symptomatic) and lesions that cannot be confidently characterized and thus require further workup. CT and MRI are the main imaging modalities used to assess the chest wall, with each having different benefits and drawbacks. Chest wall lesions can be classified according to their predominant composition: fat, calcification and ossification, soft tissue, or fluid. The identification or predominance of signal intensities or attenuation for these findings, along with the patient age, clinical history, and lesion location, can help establish the appropriate differential diagnosis. In addition, imaging findings in other organs, such as the lungs or upper abdomen, can at times provide clues to the underlying diagnosis. The authors review different chest wall lesions classified on the basis of their composition and highlight the imaging findings that can assist the radiologist in narrowing the differential diagnosis and guiding management. ©RSNA, 2022.


Assuntos
Cavidade Abdominal , Parede Torácica , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Parede Torácica/diagnóstico por imagem , Parede Torácica/patologia
3.
Cancer Control ; 28: 10732748211041221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34666555

RESUMO

BACKGROUND: Scarce data exist about colorectal cancer (CRC) presentation and outcomes in Lebanon. The aim of this study is to describe the characteristics of Lebanese patients diagnosed with colorectal cancer, particularly the method of detection, age of onset, stage at presentation, treatment modalities, and survival. METHODS: This is a retrospective study of a cohort of patients with CRC, diagnosed between 2005 and 2010, admitted to 6 major university-affiliated medical centers in Lebanon. RESULTS: The total sample consisted of 586 patients (median age: 64 years; M:F ratio: 1.25). The most common presenting symptoms were changes in bowel habits, abdominal pain, and blood per rectum. Only 3% had been diagnosed by screening colonoscopy. Of the patients diagnosed with CRC younger than 50 years of age, 72.5% had a positive family history (P = .07). More than two-thirds of patients had an advanced stage of the disease III and IV at presentation. The Kaplan-Meier-estimated survival rate was 0%, 44.5%, 70.2%, and 78.5% for those with stage IV, III, II, and I, respectively (P = .0001), and did not vary by age nor gender of the patient. There was no differential in survival estimate for patients with stage II and III by number of chemotherapy cycles received. However, there was a significant difference in median survivorship for patients with metastatic stage IV disease; those who received less than or equal to 9 cycles had a median survivorship of 2 years (CI: 1.31-2.68) compared to 4 years (CI: 2.36-5.63) for those who received more than 9 cycles (P = .047). The cox regression showed while controlling for age and gender that patients diagnosed at stage IV had a hazard ratio of 8.81 (3.20-24.22) compared to those who were diagnosed at stage I (P = .047). CONCLUSIONS: Lebanese patients affected by colorectal cancer tend to present with advanced disease stages, leading to poor prognosis and survival.


Assuntos
Neoplasias Colorretais/epidemiologia , Adulto , Idade de Início , Idoso , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Líbano/epidemiologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Estudos Retrospectivos
4.
AJR Am J Roentgenol ; 214(1): W1-W10, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593515

RESUMO

OBJECTIVE. Imaging plays an important role in the diagnosis and staging of malignancies. Many common lymphoproliferative and other solid tumor malignancies can be viral-related. CONCLUSION. This review discusses the imaging findings that can be associated with common viral-induced malignancies. Knowledge of these imaging presentations can help narrow the differential diagnosis to reach a specific diagnosis through a precise workup and proper management.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/virologia , Viroses/complicações , Neoplasias do Ânus/diagnóstico por imagem , Neoplasias do Ânus/virologia , Linfoma de Burkitt/diagnóstico por imagem , Linfoma de Burkitt/virologia , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/virologia , Feminino , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/virologia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/virologia , Masculino , Neoplasias Orofaríngeas/diagnóstico por imagem , Neoplasias Orofaríngeas/virologia , Neoplasias Penianas/diagnóstico por imagem , Neoplasias Penianas/virologia , Sarcoma de Kaposi/diagnóstico por imagem , Sarcoma de Kaposi/virologia , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/virologia
5.
Radiographics ; 40(7): 1895-1915, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33064622

RESUMO

Recreational drug use is a burgeoning health issue worldwide, with a variety of presenting symptoms and complications. These complications can be secondary to the toxic effects of the drug itself, drug impurities, and nonsterile injection. The abdominal radiologist is likely to encounter patients who use drugs recreationally and may be responsible for recognizing and reporting these acute conditions, which in some cases can be life threatening. Because these patients often present with an altered mental state and may deny or withhold information on drug use, the underlying cause may be difficult to determine. The most commonly used drugs worldwide include cocaine, cannabinoids, opioids, and amphetamines and their derivatives. Complications of use of these drugs that can be seen at abdominopelvic CT can involve multiple organ systems, including the soft tissue and gastrointestinal, genitourinary, vascular, and musculoskeletal systems. A diverse range of abdominal complications associated with these drugs can be seen at imaging, including disseminated infections, gastrointestinal ischemia, and visceral infarction. Radiologists should be familiar with the imaging findings of these complications to accurately diagnose these entities and help guide workup and patient treatment. ©RSNA, 2020.


Assuntos
Gastroenteropatias/induzido quimicamente , Gastroenteropatias/diagnóstico por imagem , Radiografia Abdominal , Uso Recreativo de Drogas , Transtornos Relacionados ao Uso de Substâncias/complicações , Doenças Urológicas/induzido quimicamente , Doenças Urológicas/diagnóstico por imagem , Doenças Vasculares/induzido quimicamente , Doenças Vasculares/diagnóstico por imagem , Humanos
6.
J Med Biol Eng ; 40(3): 419-427, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32494235

RESUMO

PURPOSE: Articular cartilage is known to be mechanically anisotropic. In this paper, the acoustic anisotropy of bovine articular cartilage and the effects of freeze-thaw cycling on acoustic anisotropy were investigated. METHODS: We developed apparatus and methods that use a magnetic L-shaped sample holder, which allowed minimal handling of a tissue, reduced the number of measurements compared to previous studies, and produced highly reproducible results. RESULTS: SOS was greater in the direction perpendicular to the articular surface compared to the direction parallel to the articular surface (N=17, P = 0.00001). Average SOS was 1,758 ± 107 m/s perpendicular to the surface, and 1,617 ± 55 m/s parallel to it. The average percentage difference in SOS between the perpendicular and parallel directions was 8.2% (95% CI: 5.4% to 11%). Freeze-thaw cycling did not have a significant effect on SOS (P>0.4). CONCLUSION: Acoustic measurement of tissue properties is particularly attractive for work in our laboratory since it has the potential for nondestructive characterization of the properties of developing engineered cartilage. Our approach allowed us to observe acoustic anisotropy of articular cartilage rapidly and reproducibly. This property was not significantly affected by freeze-thawing of the tissue samples, making cryopreservation practical for these assays.

7.
Am J Obstet Gynecol ; 217(6): 695.e1-695.e14, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29031893

RESUMO

BACKGROUND: The progestogen 17-α hydroxyprogesterone caproate (17-OHPC) is 1 of only 2 agents recommended for clinical use in the prevention of spontaneous preterm delivery, and studies of its efficacy have been conflicting. We have developed an in-vitro model to study the fetal membrane weakening process that leads to rupture in preterm premature rupture of the fetal membranes (pPROM). Inflammation/infection associated with tumor necrosis factor-α (TNF-α) induction and decidual bleeding/abruption associated thrombin release are leading causes of preterm premature rupture of the fetal membranes. Both agents (TNF-α and thrombin) cause fetal membrane weakening in the model system. Furthermore, granulocyte-macrophage colony-stimulating factor (GM-CSF) is a critical intermediate for both TNF-α and thrombin-induced fetal membrane weakening. In a previous report, we demonstrated that 3 progestogens, progesterone, 17-alpha hydroxyprogesterone (17-OHP), and medroxyprogesterone acetate (MPA), each inhibit both TNF-α- and thrombin-induced fetal membrane weakening at 2 distinct points of the fetal membrane weakening pathway. Each block both the production of and the downstream action of the critical intermediate granulocyte-macrophage colony-stimulating factor. OBJECTIVE: The objective of the study was to characterize the inhibitory effects of 17-OHPC on TNF-α- and thrombin-induced fetal membrane weakening in vitro. STUDY DESIGN: Full-thickness human fetal membrane fragments from uncomplicated term repeat cesarean deliveries were mounted in 2.5 cm Transwell inserts and cultured with/without 17-alpha hydroxyprogesterone caproate (10-9 to 10-7 M). After 24 hours, medium (supernatant) was removed and replaced with/without the addition of tumor necrosis factor-alpha (20 ng/mL) or thrombin (10 U/mL) or granulocyte-macrophage colony-stimulating factor (200 ng/mL). After 48 hours of culture, medium from the maternal side compartment of the model was assayed for granulocyte-macrophage colony-stimulating factor and the fetal membrane fragments were rupture strength tested. RESULTS: Tumor necrosis factor-alpha and thrombin both weakened fetal membranes (43% and 62%, respectively) and increased granulocyte-macrophage colony-stimulating factor levels (3.7- and 5.9-fold, respectively). Pretreatment with 17-alpha hydroxyprogesterone caproate inhibited both tumor necrosis factor-alpha- and thrombin-induced fetal membrane weakening and concomitantly inhibited the induced increase in granulocyte-macrophage colony-stimulating factor in a concentration-dependent manner. However, contrary to our prior reports regarding progesterone and other progestogens, 17-alpha hydroxyprogesterone caproate did not also inhibit granulocyte-macrophage colony-stimulating factor-induced fetal membrane weakening. CONCLUSION: 17-Alpha hydroxyprogesterone caproate blocks tumor necrosis factor-alpha- and thrombin-induced fetal membrane weakening by inhibiting the production of granulocyte-macrophage colony-stimulating factor. However, 17-alpha hydroxyprogesterone caproate did not also inhibit granulocyte-macrophage colony-stimulating factor-induced weakening. We speculate that progestogens other than 17-alpha hydroxyprogesterone caproate may be more efficacious in preventing preterm premature rupture of the fetal membranes-related spontaneous preterm birth.


Assuntos
Membranas Extraembrionárias/efeitos dos fármacos , Ruptura Prematura de Membranas Fetais/prevenção & controle , Hidroxiprogesteronas/farmacologia , Progestinas/farmacologia , Caproato de 17 alfa-Hidroxiprogesterona , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hemostáticos/farmacologia , Humanos , Técnicas In Vitro , Modelos Biológicos , Gravidez , Nascimento Prematuro/prevenção & controle , Trombina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
9.
Radiographics ; 36(5): 1390-407, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27618321

RESUMO

Life expectancies for solid organ recipients as well as graft survival rates for these patients have improved over the years because of advanced immunosuppressive therapies; however, with chronic use of these drugs, posttransplant malignancy has become one of the leading causes of morbidity for them. The risk of carcinogenesis in transplant recipients is significantly higher than for the general population and cancers tend to manifest at an advanced stage. Posttransplant malignancies are thought to develop by three mechanisms: de novo development, donor-related transmission, and recurrence of a recipient's pretransplant malignancy. Although nonmelanoma skin cancer, Kaposi sarcoma, posttransplant lymphoproliferative disorder, anogenital cancer, and lung cancer are malignancies that are thought to arise de novo, malignant melanoma and cancers that arise in the renal allograft are frequently donor related. Hepatocellular carcinomas and cholangiocarcinomas have a greater tendency to recur in liver transplant recipients. An altered or deranged immune system caused by chronic immunosuppression is considered to be one of the major contributing factors to carcinogenesis. The proposed pathogenic mechanisms for oncogenesis include impaired immunosurveillance of neoplastic cells, weakened immune activity against oncogenic viruses, and direct carcinogenic effects of immunosuppressive agents. Imaging plays an important role in screening, follow-up, and long-term surveillance in patients with malignancies because key imaging features can guide in their timely diagnosis. However, some benign entities such as transplant-related renal fibrosis, biliary necrosis, and infectious nodules in the lungs mimic malignancies and require pathologic confirmation. Management strategies that can improve malignancy-related morbidity and mortality in transplant recipients include prevention of risk factors, appropriate modulation of immunosuppressive agents, prophylaxis against infection-related malignancies, and use of intensive targeted screening programs. (©)RSNA, 2016.


Assuntos
Terapia de Imunossupressão/efeitos adversos , Neoplasias/diagnóstico por imagem , Neoplasias/etiologia , Transplante de Órgãos/efeitos adversos , Humanos , Neoplasias/epidemiologia , Fatores de Risco , Fatores de Tempo
10.
Am J Obstet Gynecol ; 213(4): 520.e1-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26070709

RESUMO

OBJECTIVE: Inflammation/infection and abruption are leading causes of preterm premature rupture of the membranes. Recently, we identified granulocyte-macrophage colony-stimulating factor (GM-CSF) as a critical mediator of both tumor necrosis factor-α- (TNF; modeling inflammation) and thrombin-induced (modeling abruption) weakening of the fetal membranes. We found that (1) TNF and thrombin both induced GM-CSF in the choriodecidua, (2) blockade of GM-CSF action with neutralizing antibodies inhibited both TNF- and thrombin-induced fetal membrane weakening, and (3) GM-CSF alone induced fetal membrane weakening. GM-CSF is thus part of an overlap of the inflammation and abruption-induced fetal membrane weakening pathways. The effects of progesterone analogs on the pathways by which fetal membranes are weakened have not been investigated. We examined the effects of progesterone, medroxyprogesterone acetate (MPA) and 17α-hydroxyprogesterone (HP) on TNF- and thrombin-induced fetal membrane weakening. STUDY DESIGN: Full-thickness fetal membranes from uncomplicated term repeat cesarean deliveries were mounted in Transwell inserts in Minimum Essential Medium alpha and incubated at 37°C in 5% CO2. The choriodecidua side of the fetal membrane fragments were preincubated with progesterone, MPA, HP, or vehicle for 24 hours. Fetal membranes were then exposed to TNF, thrombin, or GM-CSF on the choriodecidua side for an additional 48 hours. The fetal membrane tissues were then strength tested, and medium from the choriodecidua and amnion compartments was assayed for GM-CSF content. RESULTS: TNF and thrombin both weakened fetal membranes and elevated media GM-CSF levels on the choriodecidua side of the fetal membrane. Pretreatment with progesterone, MPA, or HP inhibited both TNF- and thrombin-induced fetal membrane weakening and also inhibited the induced increase in GM-CSF. GM-CSF decreased fetal membrane rupture strength by 68%, which was inhibited by progestogen pretreatment with a potency order: progesterone

Assuntos
Córion/efeitos dos fármacos , Decídua/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hemostáticos/farmacologia , Progesterona/farmacologia , Progestinas/farmacologia , Trombina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , 17-alfa-Hidroxiprogesterona/farmacologia , Membranas Extraembrionárias/efeitos dos fármacos , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Técnicas In Vitro , Acetato de Medroxiprogesterona/farmacologia , Gravidez
11.
J Anat ; 225(5): 519-26, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25146377

RESUMO

The mechanical behavior of bovine articular cartilage in shear was measured and related to its structure through the depth of the tissue. To make these measurements, we designed an apparatus that could apply controlled shear displacement and measure the resulting shear force on cartilage specimens. Shear displacement and shear strain were obtained from confocal images of photobleached lines on fluorescently stained deformed samples. Depth-dependent collagen structure was obtained using compensated polarized light microscopy. Depth-dependent shear behavior and structure of samples from two animals were measured (group A and B). Both animals were 18-24 months old, which is the range in which they are expected reach skeletal maturity. In mature samples (group A), the stiffest region was located beneath the superficial zone, and the most compliant region was found in the radial zone. In contrast, in samples that were in the process of maturing (group B) the most compliant region was located in the superficial zone. Compensated polarized light microscopy suggested that the animal from which the group A samples were obtained was skeletally mature, whereas the animal yielding the group B samples was in the process of maturing. Compensated polarized light microscopy was an important adjunct to the mechanical shear behavior in that it provided a means to reconcile differences in observed shear behavior in mature and immature cartilage. Although samples were harvested from two animals, there were clear differences in structure and shear mechanical behavior. Differences in the depth-dependent shear strain were consistent with previous studies on mature and immature samples and, based on the structural variation between mature and immature articular cartilage, their mechanical behavior differences can be tenable. These results suggest that age, as well as species and anatomic location, need to be considered when reporting mechanical behavior results.


Assuntos
Cartilagem Articular/fisiologia , Resistência ao Cisalhamento , Animais , Cartilagem Articular/anatomia & histologia , Bovinos
12.
Acad Radiol ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38395627

RESUMO

RATIONALE AND OBJECTIVES: The aim of this study was to develop a validated instrument to measure radiology residents' sense of psychological ownership of patient care. MATERIALS AND METHODS: A previously validated measure of patient care ownership was adapted through a two-step process of expert review and revision by six academic radiology faculty. An online, anonymous survey was distributed to 64 residents and fellows at the end of three consecutive four-week long rotations. We calculated Cronbach's α to determine the scale's internal consistency, performed exploratory factor analysis to identify possible subscales, and conducted bivariate and correlational analysis to establish construct validity. RESULTS: The 11-item ownership scale demonstrated good internal consistency (Cronbach's α = 0.93), and three subscales were identified corresponding to assertiveness, conscientiousness, and confidence/perceived competence. Sense of ownership was significantly associated with training level, prior experience in the type of rotation, stress, sleep, burnout, peer support, relationships with clinical staff, and recognition by department. We found no significant association between ownership and age, gender, type of rotation, site of rotation, type of residency, perceived interruption frequency, or remote work frequency. CONCLUSION: The radiology resident patient care ownership scale demonstrates good internal consistency and preliminary evidence of validity. After further validation, we expect the scale to be a valuable tool in evaluating interventions aimed at increasing radiology residents' sense of ownership.

13.
J Med Biol Eng ; 33(1): 1-16, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23606823

RESUMO

Tissue engineering (TE) has promise as a biological solution and a disease modifying treatment for arthritis. Although cartilage can be generated by TE, substantial inter- and intra-donor variability makes it impossible to guarantee optimal, reproducible results. TE cartilage must be able to perform the functions of native tissue, thus mechanical and biological properties approaching those of native cartilage are likely a pre-requisite for successful implantation. A quality-control assessment of these properties should be part of the implantation release criteria for TE cartilage. Release criteria should certify that selected tissue properties have reached certain target ranges, and should be predictive of the likelihood of success of an implant in vivo. Unfortunately, it is not currently known which properties are needed to establish release criteria, nor how close one has to be to the properties of native cartilage to achieve success. Achieving properties approaching those of native cartilage requires a clear understanding of the target properties and reproducible assessment methodology. Here, we review several main aspects of quality control as it applies to TE cartilage. This includes a look at known mechanical and biological properties of native cartilage, which should be the target in engineered tissues. We also present an overview of the state of the art of tissue assessment, focusing on native articular and TE cartilage. Finally, we review the arguments for developing and validating non-destructive testing methods for assessing TE products.

14.
Clin Imaging ; 78: 247-249, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34166884

RESUMO

We report two cases of myocarditis, in two young and previously healthy individuals, temporally related to the second dose of the mRNA-COVID-19 vaccine. Both patients developed acute chest pain, changes on electrocardiogram (ECG), and elevated serum troponin within two days of receiving their second dose. Cardiac magnetic resonance (CMR) findings were consistent with acute myocarditis.


Assuntos
COVID-19 , Miocardite , Vacinas contra COVID-19 , Humanos , Miocardite/diagnóstico por imagem , RNA Mensageiro , SARS-CoV-2
15.
Artigo em Inglês | MEDLINE | ID: mdl-32952604

RESUMO

We measured speed of sound in bovine articular cartilage as a function of compressive strain. Using techniques we developed, it was possible to apply strain starting from the unstrained, full height of a sample. Our measurements showed that speed of sound was not a monotonic function of strain as reported in earlier investigations. Speed increased with increasing strain over a range of lower strains. It reached a maximum, and then decreased as the strain increased further. These results were corroborated using a model of wave propagation in deformable porous materials. Using this model, we also established conditions under which a maximum in the speed would exist for samples in compression. Our measurements and analysis resolve the conflicting results reported in previous studies.


Assuntos
Cartilagem Articular , Animais , Bovinos , Força Compressiva , Som , Estresse Mecânico
16.
Obstet Gynecol Clin North Am ; 47(4): 523-544, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33121643

RESUMO

Using a novel in vitro model system combining biochemical/histologic with bioengineering approaches has provided significant insights into the physiology of fetal membrane weakening and rupture along with potential mechanistic reasons for lack of efficacy of currently clinically used agents to prevent preterm premature rupture of the membranes (pPROM) and preterm births. Likewise, the model has also facilitated screening of agents with potential for preventing pPROM and preterm birth.


Assuntos
Membranas Extraembrionárias/metabolismo , Ruptura Prematura de Membranas Fetais/metabolismo , Ruptura Prematura de Membranas Fetais/prevenção & controle , Membranas Extraembrionárias/fisiopatologia , Feminino , Ruptura Prematura de Membranas Fetais/fisiopatologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Recém-Nascido , Modelos Biológicos , Gravidez , Nascimento Prematuro/prevenção & controle , Progesterona/metabolismo , Ácido Tióctico/metabolismo , Trombina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
Placenta ; 89: 1-7, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31665659

RESUMO

INTRODUCTION: We have previously demonstrated two associations of PPROM, (1) inflammation/infection (modeled by tumor necrosis factor (TNF)) and (2) decidual bleeding (modeled by thrombin), both decrease fetal membrane (FM) rupture strength in-vitro. Furthermore, Granulocyte-Macrophage-Colony-Stimulating-Factor (GM-CSF) induced by both TNF and thrombin is a critical intermediate, necessary and sufficient for weakening by either agent. The amnion is the strength component of FM and must weaken for FM to rupture. It is unclear whether GM-CSF weakens amnion (AM) directly, or initially targets choriodecidua (CD) which secondarily releases agents to act on amnion. METHODS: Full thickness FM fragments were treated with/without GM-CSF. Some were preincubated with alpha-lipoic acid (LA), a known inhibitor of FM weakening. The FM fragments were then strength-tested. Separately, FM fragments were initially separated to AM and CD. AM fragments were cultured with Medium ± GM-CSF and then strength-tested. In other experiments, CD fragments were cultured with Medium, GM-CSF, LA, or LA + GM-CSF. Conditioned medium from each group was then incubated with AM. AM was then strength-tested. Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Matrix Metalloproteinases (TIMPs) were analyzed by Mutiplex Elisa. RESULTS: GM-CSF weakened intact FM which was blocked by LA. GM-CSF did not weaken isolated AM. However, GM-CSF conditioned CD media weakened AM and this weakening was inhibited by LA. GM-CSF treatment of CD increased MMPs 2, 9, and 10, and decreased TIMPs 1-3. LA reversed these effects. CONCLUSIONS: GM-CSF does not weaken amnion directly; GM-CSF acts on CD to increase proteases and decrease anti-proteases which secondarily weaken the amnion.


Assuntos
Âmnio/efeitos dos fármacos , Córion/efeitos dos fármacos , Ruptura Prematura de Membranas Fetais/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Metaloproteinases da Matriz/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Âmnio/metabolismo , Córion/metabolismo , Meios de Cultivo Condicionados , Feminino , Humanos , Gravidez , Ácido Tióctico/farmacologia
18.
Cureus ; 10(3): e2370, 2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-29805939

RESUMO

Bouveret's syndrome, first described in 1896, is an unusual cause of gastric outlet obstruction secondary to large gallstone impaction in the proximal duodenum after migration through a cholecystoduodenal fistula. Stone migration has been previously described after endoscopic or surgical fragmentation. However, this is the first reported case, in our knowledge, where the stone migrated after oral contrast administration a few days after the onset of symptoms, causing a distal gallstone ileus.

19.
Placenta ; 68: 9-14, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30055672

RESUMO

INTRODUCTION: We established an in-vitro model for the study of human fetal membrane (FM) weakening leading to pPROM. In this model, granulocyte-macrophage colony-stimulating factor (GM-CSF) is a critical intermediate for both tumor necrosis factor-α (TNF; modeling infection/inflammation) and thrombin (modeling decidual bleeding/abruption)-induced weakening. Thus, inhibitors of FM weakening can be categorized as targeting GM-CSF production, GM-CSF downstream action, or both. Most progestogens inhibit both, except 17-α hydroxyprogesterone caproate which inhibits FM weakening at only one point, GM-CSF production. α-lipoic acid (LA), an over-the-counter dietary supplement, has also been previously shown to inhibit TNF and thrombin induced FM weakening. OBJECTIVE: To determine the point of action of LA inhibition of FM weakening. METHODS: FM fragments were mounted in Transwell inserts and preincubated with/without LA/24 h, then with/without addition of TNF, thrombin or GM-CSF. After 48 h, medium was assayed for GM-CSF, and FM fragments were rupture-strength tested. RESULTS: TNF and thrombin both weakened FM and increased GM-CSF levels. GM-CSF also weakened FM. LA inhibited both TNF and thrombin induced FM weakening and concomitantly inhibited the increase in GM-CSF in a concentration-dependent manner. In addition, LA inhibited GM-CSF induced FM weakening in a concentration dependent manner. CONCLUSIONS: LA blocks TNF and thrombin induced FM weakening at two points, inhibiting both GM-CSF production and downstream action. Thus, we speculate that LA may be a potential standalone therapeutic agent, or supplement to current therapy for prevention of pPROM related spontaneous preterm birth, if preclinical studies to examine feasibility and safety during pregnancy are successfully accomplished.


Assuntos
Membranas Extraembrionárias/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Inflamação/metabolismo , Ácido Tióctico/farmacologia , Ruptura Prematura de Membranas Fetais/metabolismo , Humanos , Técnicas In Vitro , Trombina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
20.
Tissue Eng Part C Methods ; 24(8): 443-456, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29999475

RESUMO

Previous investigations have shown that tissue-engineered articular cartilage can be damaged under a combination of compression and sliding shear. In these cases, damage was identified in histological sections after a test was completed. This approach is limited, in that it does not identify when damage occurred. This especially limits the utility of an assay for evaluating damage when comparing modifications to a tissue-engineering protocol. In this investigation, the feasibility of using ultrasound (US) to detect damage as it occurs was investigated. US signals were acquired before, during, and after sliding shear, as were stereomicroscope images of the cartilage surface. Histology was used as the standard for showing if a sample was damaged. We showed that US reflections from the surface of the cartilage were attenuated due to roughening following sliding shear. Furthermore, it was shown that by scanning the transducer across a sample, surface roughness and erosion following sliding shear could be identified. Internal delamination could be identified by the appearance of new echoes between those from the front and back of the sample. Thus, it is feasible to detect damage in engineered cartilage using US.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Estresse Mecânico , Engenharia Tecidual/métodos , Ultrassonografia , Animais , Bovinos , Força Compressiva , Coelhos , Propriedades de Superfície , Suporte de Carga
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