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1.
Parasite Immunol ; 46(2): e13025, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38372623

RESUMO

Trichomonas vaginalis (Tv) is a parasite that causes trichomoniasis, a prevalent sexually-transmitted infection. Neutrophils are found at the site of infection, and can rapidly kill the parasite in vitro, using trogocytosis. However, the specific molecular players in neutrophil killing of Tv are unknown. Here, we show that complement proteins play a role in Tv killing by human neutrophil-like cells (NLCs). Using CRISPR/Cas9, we generated NLCs deficient in each of three complement receptors (CRs) known to be expressed on human neutrophils: CR1, CR3, and CR4. Using in vitro trogocytosis assays, we found that CR3, but not CR1 or CR4 is required for maximum trogocytosis of the parasite by NLCs, with NLCs lacking CR3 demonstrating ~40% reduction in trogocytosis, on average. We also observed a reduction in NLC killing of Tv in CR3 knockout, but not CR1 or CR4 knockout NLCs. On average, NLCs lacking CR3 had ~50% reduction in killing activity. We also used a parallel approach of pre-incubating NLCs with blocking antibodies against CR3, which similarly reduced NLC killing of parasites. These data support a model in which Tv is opsonized by the complement protein iC3b, and bound by neutrophil CR3 receptor, to facilitate trogocytic killing of the parasite.


Assuntos
Parasitos , Trichomonas vaginalis , Humanos , Animais , Antígeno de Macrófago 1 , Trichomonas vaginalis/genética , Neutrófilos , Antígeno CD11b
2.
Vet Res Commun ; 48(2): 865-875, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37968413

RESUMO

The protozoan parasite Tritrichomonas foetus (T. foetus) is the causative organism of bovine trichomonosis (also referred to as trichomoniasis), a sexually-transmitted infection that reduces fertility in cattle. Efforts to control trichomonosis on cattle farms are hindered by the discouragement of antibiotic use in agriculture, and the incomplete, short-lived protection conferred by the current vaccines. A more complete mechanistic understanding of what effective immunity to T. foetus entails could enable the development of more robust infection control strategies. While neutrophils, the primary responders to infection, are present in infected tissues and have been shown to kill the parasite in vitro, the mechanism they use for parasite killing has not been established. Here, we show that primary bovine neutrophils isolated from peripheral blood rapidly kill T. foetus in vitro in a dose-dependent manner, and that optimal parasite killing is reduced by inhibitors of trogocytosis. We also use imaging to show that bovine neutrophils surround T. foetus and trogocytose its membrane. These findings are consistent with killing via trogocytosis, a recently described novel neutrophil antimicrobial mechanism.


Assuntos
Doenças dos Bovinos , Parasitos , Infecções Protozoárias em Animais , Tritrichomonas foetus , Bovinos , Animais , Neutrófilos , Trogocitose , Doenças dos Bovinos/parasitologia , Infecções Protozoárias em Animais/parasitologia , Infecções Protozoárias em Animais/prevenção & controle
3.
Parasite Immunol ; 45(12): e13011, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37776091

RESUMO

The protozoan parasite Toxoplasma gondii infects approximately 2.5 billion people worldwide. Infection induces a rapid dissemination of parasites throughout the body followed by the formation of lifelong cysts within neurons of the host brain. Both stages require a dynamic immune response comprised of both innate and adaptive cells. Neutrophils are a primary responding cell to acute infection and have been observed in the brain during murine chronic infection. Previous studies investigating human neutrophils found that invasion by Toxoplasma tachyzoites inhibits apoptosis of neutrophils, prolonging their survival under inflammatory conditions. Here, we demonstrate the differentiation of two distinct subsets following exposure of human neutrophil-like-cells (HNLC) to Toxoplasma cysts. In vitro stimulation and imaging studies show cyst-specific induction of cytokines and cyst clearance by HNLCs. Further testing demonstrates that aged HNLCs perform less phagocytosis of cysts compared to non-aged HNLCs. In conclusion, this study identifies a novel response of HNLCs to Toxoplasma cysts and may indicate a role for neutrophils in the clearance of cysts during human infection with Toxoplasma.


Assuntos
Anti-Infecciosos , Toxoplasma , Humanos , Animais , Camundongos , Idoso , Neutrófilos , Encéfalo/parasitologia , Citocinas
4.
Cleft Palate Craniofac J ; : 10556656231154814, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36972482

RESUMO

Osteosarcomas arising within the pterygomaxillary/infratemporal fossa region are rare among the pediatric population. Survival rates are most influenced by tumor resection with negative margins, which can be dependent on surgical accessibility of the tumor site. The pterygomaxillary/infratemporal fossa location poses several challenges to safe and adequate tumor resection, including proximity of the facial nerve and great vessels and scarring associated with traditional transfacial approaches. In this article, we present the case of a 6-year-old boy with an osteosarcoma of the left pterygomaxillary/infratemporal fossa region successfully managed with an "oncoplastic" approach, incorporating the use of CAD/CAM and mixed reality technologies.

5.
Cureus ; 14(8): e28225, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36158330

RESUMO

Introduction The Florida International University (FIU) Green Family Neighborhood Health Education Learning Program (NeighborhoodHELP) in Miami-Dade County serves communities impacted by adverse social determinants of health. This study identified sociodemographic factors affecting control of diabetes and hypertension among NeighborhoodHELP patients. Methods This non-concurrent cohort study evaluated NeighborhoodHELP patients who received care at mobile health centers (MHCs) utilizing de-identified data extracted from the MHCs' clinical quality metrics data set for the 2018-2019 fiscal year. A total of 143 eligible adults with diabetes and 222 adults with hypertension were identified. Condition control was defined as blood pressure ≤ 130 mmHg (systolic) and ≤ 80 mmHg (diastolic) or hemoglobin A1c (HbA1c) ≤ 7% (diabetes). Association with age, gender, ethnicity, marital status, language, service area, income per-capita, and medical student assignment was explored using logistic regression. Results The model showed decreased diabetes control likelihood among Haitian-Creole speakers (OR: 0.13; 95% CI: 0.02-0.75). Odds of diabetes control were greater in two discrete areas serviced by the program, one known as Hippocrates (OR: 4.9; 95% CI: 1.23-19.37) and the other Semmelweis (OR: 3.71; 95% CI: 1.07-12.83). Income greater than $10,000 increased hypertension control likelihood (OR: 2.22; 95% CI: 1.03-4.8). Conclusions Among NeighborhoodHELP patients, geographic region and language impact diabetes control, while income affects hypertension control. Further research is warranted to identify the role of other factors.

6.
Abdom Radiol (NY) ; 46(3): 909-918, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32936419

RESUMO

PURPOSE: To evaluate how initial abdominopelvic CT findings and staging correlate with outcomes in a cohort of patients aged 18-40 years. METHODS: We evaluated all young adult patients at a single tertiary center diagnosed with histopathologically confirmed CRC who also had CT of the abdomen and pelvis at the time of initial diagnosis. Demographics, symptoms, CT findings, staging, treatments, and outcomes at 1 year and 5 years were recorded. RESULTS: Of 91 patients who met initial inclusion criteria, 81.8% had a mass present on CT, with an average size of 4.8 cm ± 2.9. A majority of patients were surgical stage III or IV (64.3%). Advanced AJCC stage was more common with rectal tumors and metastatic disease on initial CT (p < 0.0001). In a subgroup analysis, almost all patients initially staged 4A or higher had progression of disease. At the final follow-up visit, by RECIST 1.1 criteria, 58.8% had progressive disease, 35.3% complete response, and 3.9% stable disease. The overall 5-year survival rate in this subgroup was 40% with lower survival probability with increasing stage (p = 0.0001). CONCLUSION: Most young adult patients presented with large tumors on imaging, increasing the likelihood of identification on CT. Tumors initially presenting in the rectum with enlarged lymph nodes and/or with distant metastases on CT were more often associated with advanced surgical stage and poorer prognosis. A majority of patients presented at an advanced stage, most commonly stage 4A, and had progression of disease at follow-up.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Retais , Humanos , Estadiamento de Neoplasias , Reto , Tomografia Computadorizada por Raios X , Adulto Jovem
7.
Cureus ; 10(12): e3686, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30761238

RESUMO

A supernumerary kidney is extremely rare, with less than 100 cases currently reported in the literature. When this variant is present, the additional renal parenchyma demonstrates its own collecting system, vascular supply, and distinct encapsulated parenchyma. Herein, we discuss the case of a supernumerary kidney in a 20-year-old male.

8.
Cureus ; 9(8): e1634, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-29104842

RESUMO

Multiple myeloma (MM) and osteosarcoma (OS) are two common bone malignancies, however, the simultaneous occurrence of both primary bone tumors in the same patient has not been reported in the United States to date. We present a unique case in which both malignancies present concurrently in a 72-year-old man. Results of spinal magnetic resonance imaging (MRI), radiographic skeletal survey, and hematological workup established the initial diagnosis of MM. Approximately three months later, the patient was admitted with severe right hip pain and shortness of breath and was evaluated with computed tomography (CT) of the right hip, abdomen, pelvis, and chest, revealing an osseous mass with a "sunburst" pattern in the right hip, and several calcified nodules in the lungs. Subsequent wedge resection and histological evaluation of the lung nodules confirmed the diagnosis of metastatic OS to the lungs, with a presumptive diagnosis of primary OS of the right hip. The clinical findings and imaging characteristics in this case are presented. Two similar cases found in the literature are also briefly discussed. The findings of this case report suggest that, in rare instances, MM patients with sclerotic bone findings may have a concurrent diagnosis of OS.

9.
Case Rep Cardiol ; 2017: 7298347, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848680

RESUMO

We report a case of a 39-year-old male who presented to the emergency department with acute chest pain while being in remission from T-cell acute lymphoblastic leukemia (T-ALL). Cardiac markers were elevated and EKG revealed ischemic changes compatible with acute myocardial ischemia. Coronary computed tomography angiography (CCTA) showed calcium-free coronary arteries and soft tissue myocardial infiltration suggestive of cardiac leukemia. A bone marrow biopsy confirmed recurrence of T-ALL, and patient was successfully treated with chemotherapy. We discuss the prospective diagnosis of myopericardial leukemic involvement and the role of CCTA in diagnosis and perform a literature review.

10.
Cureus ; 8(8): e737, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27660736

RESUMO

Paget's disease of the bone, historically known as osteitis deformans, is an uncommon disease typically affecting individuals of European descent. Patients with Paget's disease of the bone are at increased risk for primary bone neoplasms, particularly osteosarcoma. Many cases of metastatic disease to pagetic bone have been reported. However, renal cell carcinoma metastasized to pagetic bone is extremely rare. A 94-year-old male presented to the emergency department complaining of abdominal pain. A computed tomography scan of the abdomen demonstrated a large mass in the right kidney compatible with renal cell carcinoma. The patient was also noted to have Paget's disease of the pelvic bones and sacrum. Within the pagetic bone of the sacrum, there was an enhancing mass compatible with renal cell carcinoma. A subsequent biopsy of the renal lesion confirmed renal cell carcinoma. Paget's disease of the bone places the patient at an increased risk for bone neoplasms. The most commonly reported sites for malignant transformation are the femur, pelvis, and humerus. In cases of malignant transformation, osteosarcoma is the most common diagnosis. Breast, lung, and prostate carcinomas are the most common to metastasize to pagetic bone. Renal cell carcinoma associated with Paget's disease of the bone is very rare, with only one prior reported case. Malignancy in Paget's disease of the bone is uncommon with metastatic disease to pagetic bone being extremely rare. We report a patient diagnosed with concomitant renal cell carcinoma and metastatic disease within Paget's disease of the sacrum. Further research is needed to assess the true incidence of renal cell carcinoma associated with pagetic bone.

11.
Cureus ; 8(12): e930, 2016 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-28097081

RESUMO

Lymphoma can involve any organ or tissue that contains lymphoid tissue and the heart is no exception. A few prior case reports have described lymphoma encasing a coronary artery or involving one or more cardiac valves. We present a rare case of diffuse large B-cell lymphoma (DLBCL) involving the tricuspid valve and right coronary artery diagnosed on coronary CT angiography. The clinical and imaging characteristics of cardiac lymphoma are discussed.

12.
Nat Chem ; 5(9): 757-61, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23965677

RESUMO

High shear stresses are known to trigger destructive bond-scission reactions in polymers. Recent work has shown that the same shear forces can be used to accelerate non-destructive reactions in mechanophores along polymer backbones, and it is demonstrated here that such mechanochemical reactions can be used to strengthen a polymer subjected to otherwise destructive shear forces. Polybutadiene was functionalized with dibromocyclopropane mechanophores, whose mechanical activation generates allylic bromides that are crosslinked in situ by nucleophilic substitution reactions with carboxylates. The crosslinking is activated efficiently by shear forces both in solvated systems and in bulk materials, and the resulting covalent polymer networks possess moduli that are orders-of-magnitude greater than those of the unactivated polymers. These molecular-level responses and their impact on polymer properties have implications for the design of materials that, like biological materials, actively remodel locally as a function of their physical environment.


Assuntos
Butadienos/química , Elastômeros/química , Ácidos Carboxílicos/química , Ciclopropanos/química , Resistência ao Cisalhamento
14.
J Am Chem Soc ; 134(31): 12939-42, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22817476

RESUMO

Force-induced transformations of polymer-bound functionalities have the potential to produce a rich array of stress-responsive behavior. One area of particular interest is the activation of non-scissile mechanophores in which latent reactivity can be unveiled that, under the appropriate conditions, could lead to constructive bond formation in materials exposed to typically destructive stress. Here, the mechanical activation of a bicyclo[3.2.0]heptane (BCH) mechanophore is demonstrated via selective labeling of bis-enone products. BCH ring-opening produces large local elongation (>4 Å) and products that are reactive to conjugate additions under mild conditions. Subsequent photocyclization regenerates the initial BCH functionality, providing switchable structure and reactivity along the polymer backbone in response to stress and visible light.


Assuntos
Compostos Bicíclicos com Pontes/química , Heptanos/química , Processos Fotoquímicos , Catálise , Química Click , Ciclização , Fenômenos Mecânicos , Estrutura Molecular
15.
J Am Chem Soc ; 134(23): 9577-80, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22650366

RESUMO

Epoxidized polybutadiene and epoxidized polynorbornene were subjected to pulsed ultrasound in the presence of small molecules capable of being trapped by carbonyl ylides. When epoxidized polybutadiene was sonicated, there was no observable small molecule addition to the polymer. Concurrently, no appreciable isomerization (cis to trans epoxide) was observed, indicating that the epoxide rings along the backbone are not mechanically active under the experimental conditions employed. In contrast, when epoxidized polynorbornene was subjected to the same conditions, both addition of ylide trapping reagents and net isomerization of cis to trans epoxide were observed. The results demonstrate the mechanical activity of epoxides, show that mechanophore activity is determined not only by the functional group but also the polymer backbone in which it is embedded, and facilitate a characterization of the reactivity of the ring-opened dialkyl epoxide.

16.
ACS Macro Lett ; 1(1): 23-27, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35578474

RESUMO

The high shear forces generated during the pulsed ultrasound of dilute polymer solutions lead to large tensile forces that are focused near the center of the polymer chain, but quantitative experimental evidence regarding the force distribution is rare. Here, pulsed ultrasound of quantitatively geminal-dihalocyclopropanated (gDHC) polybutadiene provides insights into the distribution. Pulsed ultrasound leads to the mechanochemical ring-opening of the gDHC mechanophore to a 2,3-dihaloalkene. The alkene product is then degraded through ozonolysis to leave behind only those stretches of the polymer that have not experienced large enough forces to be activated. Microstructural and molecular weight analysis reveals that the activated and unactivated regions of the polymer are continuous, indicating a smooth and monotonic force distribution from the midchain peak toward the polymer ends. When coupled to chain scission, the net process constitutes the rapid, specific, and reagentless conversion of a single homopolymer into block copolymers. Despite their compositional polydispersity, the sonicated polymers assemble into ordered lamellar phases that are characterized by small-angle X-ray scattering.

17.
Environ Sci Technol ; 38(19): 5022-9, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15506194

RESUMO

Our paper reports on the reactivities and orientations of two common phenols, phenol (2) and m-cresol (3), and some of their chlorinated intermediates with aqueous monochloramine, NH2Cl, and dichloramine, NHCl2. We also examined the further reactivity of 2,4,6-trichlorophenol (4) with the chloramines. The phenols are an important area of investigation because they are substituents in the humic acids and are common contaminants in water. m-Cresol (3) was found to be more reactive than phenol (2)with both chlorinating agents. Both NH2Cl and NHCl2were sufficiently reactive to chlorinate all positions ortho and para to the hydroxyl groups. Mono- and dichloramine showed the same orientation with 2 but different orientations in their reactions with the substituent phenols. Indophenol (as its salt) was formed to a minor extent at high pH but not at pH 9. Both NH2Cl and NHCl2 rapidly replaced the parachlorine in 2,4,6-trichlorophenol (4) to give a mixture of 2,6-dichloro-1,4-benzoquinone-4-(N-chloro) imine (5) and 2,6-dichloro-1,4-benzoquinone (18). Similar reactions occurwith 2,4,6-trichloro-m-cresol (17) and 2,4,6-trichloro-3-methoxyphenol (29). The products for 17 were confirmed by mass spectrometry (El and Cl), 1H NMR, 13C NMR, and IR; the products for 29 were confirmed by mass spectrometry (El and Cl) and IR. An ion radical mechanism is suggested to account for the chlorine replacement by the chloramines. [No side chain oxidation of the methyl group in 17 in H20 or ether occurred, with or without ultraviolet radiation.] Both 5 and 18 underwent further chlorination with NH2Cl or NHCl2. Imine 5 did not function as a chlorinated agent.


Assuntos
Cloraminas/química , Desinfetantes/química , Modelos Teóricos , Fenol/química , Poluentes da Água/análise , Cresóis/química , Substâncias Húmicas , Fotoquímica , Raios Ultravioleta
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