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1.
Cell Rep ; 42(10): 113253, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37819760

RESUMEN

Sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the brain microcirculation is a hallmark of cerebral malaria (CM), which leads to endothelial activation, brain swelling, and death. Here, we probed CM inflammation in a perfusable 3D human brain microvessel model. 3D brain microvessels supported in vivo-like capacities for parasite binding and maturation in situ, leading to a distinct inflammatory response from the pro-inflammatory cytokine tumor necrosis factor α (TNF-α). By combining transcriptional analysis, imaging, and leukocyte perfusion, we showed that whereas TNF-α promotes a reversible inflammatory phenotype with widespread leukocyte recruitment, parasites induce unique stress response pathways and cause localized cell adhesivity changes, focal endothelial disruptions, and apoptosis. Furthermore, parasites modified the temporal kinetics of the TNF transcriptional response, suggesting augmented inflammatory damage with the two sequential stimuli. Our findings offer mechanistic insights into CM biology in a 3D brain microvessel mimetic platform and suggest that multiple events intersect to promote brain barrier inflammation in CM.


Asunto(s)
Malaria Cerebral , Malaria Falciparum , Humanos , Factor de Necrosis Tumoral alfa , Encéfalo/patología , Plasmodium falciparum/genética , Inflamación/patología , Microvasos/patología , Eritrocitos/parasitología , Malaria Falciparum/parasitología
2.
Neurobiol Dis ; 181: 106125, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37062307

RESUMEN

In Alzheimer's disease (AD), secretion and deposition of amyloid beta peptides (Aß) have been associated with blood-brain barrier dysfunction. However, the role of Aß in endothelial cell (EC) dysfunction remains elusive. Here we investigated AD mediated EC activation by studying the effect of Aß secreted from human induced pluripotent stem cell-derived cortical neurons (hiPSC-CN) harboring a familial AD mutation (Swe+/+) on human brain microvascular endothelial cells (HBMECs) in 2D and 3D perfusable microvessels. We demonstrated that increased Aß levels in Swe+/+ conditioned media (CM) led to stress fiber formation and upregulation of genes associated with endothelial inflammation and immune-adhesion. Perfusion of Aß-rich Swe+/+ CM induced acute formation of von Willebrand factor (VWF) fibers in the vessel lumen, which was attenuated by reducing Aß levels in CM. Our findings suggest that Aß peptides can trigger rapid inflammatory and thrombogenic responses within cerebral microvessels, which may exacerbate AD pathology.


Asunto(s)
Enfermedad de Alzheimer , Células Madre Pluripotentes Inducidas , Humanos , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Células Endoteliales/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Microvasos/metabolismo , Neuronas/metabolismo , Secretoma
3.
Methods Mol Biol ; 2470: 557-585, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35881375

RESUMEN

P. falciparum-infected red blood cell (iRBC) sequestration in the microvasculature is a pivotal event in severe malaria pathogenesis. In vitro binding assays using endothelial cell monolayers under static and flow conditions have revealed key ligand-receptor interactions for iRBC sequestration. However, mechanisms remain elusive for iRBC sequestration in specific vascular locations, which prevents further development of effective therapies. New models are needed to better recapitulate the complex geometry of blood flow in human blood vessels and organ-specific vascular signatures. Recent advances in engineering 3D microvessels in vitro have emerged as promising technologies to not only model complex human vascular structures but also allow for precise and step-wise control of individual biological and biomechanical parameters. By designing networks with different branching structures and change of vessel diameter along the flow path, these models recapitulate pressure and flow changes occurring in vivo. Here, we describe the methodology employed to build 3D microvessels using soft lithography and injection molding techniques, as well as the protocol to fabricate capillary-size vessels through collagen photoablation. Furthermore, we describe the methodology of using these models to study malaria and narrate necessary steps for perfusion of P. falciparum through 3D microvessels and different options to quantify P. falciparum-iRBC binding.


Asunto(s)
Malaria Falciparum , Plasmodium falciparum , Adhesión Celular , Eritrocitos/patología , Humanos , Malaria Falciparum/patología , Microvasos , Plasmodium falciparum/metabolismo
4.
J Spec Oper Med ; 22(1): 9, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35278311
5.
Pediatr Emerg Care ; 38(1): 17-21, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32544142

RESUMEN

OBJECTIVE: The objective of this study was to assess the use of a color-only method syringe for accuracy and timeliness when administrating midazolam. This method was compared with a U.S. Food and Drug Administration (FDA)-approved validation method. METHODS: A prospective, randomized, crossover trial was conducted to compare the dosing accuracy and timeliness of the color-only syringe method versus the validation method. Twenty-five participants prepared pediatric midazolam doses according to their preferred method, a FDA-approved validation method, and a color-only method. Primary endpoints included dosing accuracy and time to medication administration. RESULTS: The preferred 3-kg calculations had a median margin of error of 5.6% and a median time to completion of 55.6 seconds. The color-only method took less time to complete than the validation method (median time: 29.5 seconds vs 58.2 seconds). There was no statistically significant difference in errors between the color-only method and the validation method. None of the participants reported a mistake using the color-only method, whereas 25% (5/20) reported a mistake using the validation method. Only 20% (4/20) of participants believed that the validation method found or eliminated any mistakes. There were 8 medication errors identified when participants used the method of choice, 4 with the validation method, and 1 with the color-only method. CONCLUSIONS: There was no significant difference in dosing errors between the FDA-approved validation method and the color-only method. Use of a color-only method did reduced time to medication administration when compared with a preferred method and an FDA-approved validation method.


Asunto(s)
Midazolam , Jeringas , Niño , Estudios Cruzados , Humanos , Estudios Prospectivos , Estados Unidos , United States Food and Drug Administration
6.
J Histotechnol ; 45(1): 10-20, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34496720

RESUMEN

Falloposcopy is the endoscopic examination of the fallopian tubes, which are challenging to access due to their deep body location, small opening from the uterus, and lumen filled with plicae. We and others have developed endoscopes that are inserted through the uterus guided by a hysteroscope into the tubal ostium. To better understand how to utilize these endoscopes either as standalone devices or in concert with everting delivery balloons, a preliminary study of anatomy and mechanical behavior was performed ex vivo on porcine and human fallopian tubes. Segments of fallopian tubes from the isthmus, ampulla and infundibulum were inflated with saline either to bursting or held at sub-burst pressures with saline or a saline-filled balloon. Formalin fixed, paraffin embedded tissue sections stained with Masson's trichrome were examined for damage to the mucosa and muscularis. Porcine fallopian tubes tolerated saline pressurization at 15 psi for 1 minute without morphological damage. Balloon inflation to 15 psi caused no apparent damage to the muscle layer or rupture of the fallopian tube, but balloon movement within the tube can denude the mucosal epithelial layer. Human fallopian tubes averaged higher burst pressure values than porcine tubes. Under pressurization, the external tube diameter expanded by minimal to moderate amounts. Human and porcine tissues were similar in histological appearance. These studies suggest that moderate pressurization is acceptable but will not appreciably expand the fallopian tube diameter. The results also indicate that pigs are a reasonable model to study damage from falloscopy as seen in human tissue.


Asunto(s)
Trompas Uterinas , Laparoscopía , Animales , Endoscopios , Trompas Uterinas/patología , Femenino , Humanos , Histeroscopios , Porcinos , Útero
7.
Toxicol Sci ; 185(1): 64-76, 2021 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-34718823

RESUMEN

Benzene is a ubiquitous environmental pollutant abundant in household products, petrochemicals, and cigarette smoke. Benzene is a well-known carcinogen in humans and experimental animals; however, little is known about the cardiovascular toxicity of benzene. Recent population-based studies indicate that benzene exposure is associated with an increased risk for heart failure. Nonetheless, it is unclear whether benzene exposure is sufficient to induce and/or exacerbate heart failure. We examined the effects of benzene (50 ppm, 6 h/day, 5 days/week, and 6 weeks) or high-efficiency particulate absorbing-filtered air exposure on transverse aortic constriction (TAC)-induced pressure overload in male C57BL/6J mice. Our data show that benzene exposure had no effect on cardiac function in the Sham group; however, it significantly compromised cardiac function as depicted by a significant decrease in fractional shortening and ejection fraction, as compared with TAC/Air-exposed mice. RNA-seq analysis of the cardiac tissue from the TAC/benzene-exposed mice showed a significant increase in several genes associated with adhesion molecules, cell-cell adhesion, inflammation, and stress response. In particular, neutrophils were implicated in our unbiased analyses. Indeed, immunofluorescence studies showed that TAC/benzene exposure promotes infiltration of CD11b+/S100A8+/myeloperoxidase+-positive neutrophils in the hearts by 3-fold. In vitro, the benzene metabolites, hydroquinone, and catechol, induced the expression of P-selectin in cardiac microvascular endothelial cells by 5-fold and increased the adhesion of neutrophils to these endothelial cells by 1.5- to 2.0-fold. Benzene metabolite-induced adhesion of neutrophils to the endothelial cells was attenuated by anti-P-selectin antibody. Together, these data suggest that benzene exacerbates heart failure by promoting endothelial activation and neutrophil recruitment.


Asunto(s)
Insuficiencia Cardíaca , Remodelación Ventricular , Animales , Benceno/toxicidad , Células Endoteliales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Remodelación Ventricular/fisiología
8.
Am J Physiol Heart Circ Physiol ; 321(4): H784-H797, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34533403

RESUMEN

Coenzyme A (CoA) is an essential cofactor required for intermediary metabolism. Perturbations in homeostasis of CoA have been implicated in various pathologies; however, whether CoA homeostasis is changed and the extent to which CoA levels contribute to ventricular function and remodeling during pressure overload has not been explored. In this study, we sought to assess changes in CoA biosynthetic pathway during pressure overload and determine the impact of limiting CoA on cardiac function. We limited cardiac CoA levels by deleting the rate-limiting enzyme in CoA biosynthesis, pantothenate kinase 1 (Pank1). We found that constitutive, cardiomyocyte-specific Pank1 deletion (cmPank1-/-) significantly reduced PANK1 mRNA, PANK1 protein, and CoA levels compared with Pank1-sufficient littermates (cmPank1+/+) but exerted no obvious deleterious impact on the mice at baseline. We then subjected both groups of mice to pressure overload-induced heart failure. Interestingly, there was more ventricular dilation in cmPank1-/- during the pressure overload. To explore potential mechanisms contributing to this phenotype, we performed transcriptomic profiling, which suggested a role for Pank1 in regulating fibrotic and metabolic processes during the pressure overload. Indeed, Pank1 deletion exacerbated cardiac fibrosis following pressure overload. Because we were interested in the possibility of early metabolic impacts in response to pressure overload, we performed untargeted metabolomics, which indicated significant changes to metabolites involved in fatty acid and ketone metabolism, among other pathways. Collectively, our study underscores the role of elevated CoA levels in supporting fatty acid and ketone body oxidation, which may be more important than CoA-driven, enzyme-independent acetylation in the failing heart.NEW & NOTEWORTHY Changes in CoA homeostasis have been implicated in a variety of metabolic diseases; however, the extent to which changes in CoA homeostasis impacts remodeling has not been explored. We show that limiting cardiac CoA levels via PANK deletion exacerbated ventricular remodeling during pressure overload. Our results suggest that metabolic alterations, rather than structural alterations, associated with Pank1 deletion may underlie the exacerbated cardiac phenotype during pressure overload.


Asunto(s)
Metabolismo Energético , Miocardio/enzimología , Fosfotransferasas (Aceptor de Grupo Alcohol)/deficiencia , Disfunción Ventricular Izquierda/enzimología , Función Ventricular Izquierda , Remodelación Ventricular , Animales , Aorta/fisiopatología , Aorta/cirugía , Apoptosis , Presión Arterial , Coenzima A/metabolismo , Modelos Animales de Enfermedad , Femenino , Fibrosis , Eliminación de Gen , Humanos , Masculino , Metaboloma , Ratones Endogámicos C57BL , Ratones Noqueados , Miocardio/patología , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Transcriptoma , Disfunción Ventricular Izquierda/genética , Disfunción Ventricular Izquierda/patología , Disfunción Ventricular Izquierda/fisiopatología
9.
J Mol Cell Cardiol ; 159: 1-13, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34118217

RESUMEN

Organ-on-a-chip (OOC) platforms involve the miniaturization of cell culture systems and enable a variety of novel experimental approaches. These range from modeling the independent effects of biophysical forces on cells to screening novel drugs in multi-organ microphysiological systems, all within microscale devices. As in living systems, the incorporation of vascular structure is a key feature common to almost all organ-on-a-chip systems. In this review we highlight recent advances in organ-on-a-chip technologies with a focus on the vasculature. We first present the developmental process of the blood vessels through which vascular cells assemble into networks and remodel to form complex vascular beds under flow. We then review self-assembled vascular models and flow systems for the study of vascular development and biology as well as pre-patterned vascular models for the generation of perfusable microvessels for modeling vascular and tissue function. We finally conclude with a perspective on developing future OOC approaches for studying different aspects of vascular biology. We highlight the fit for purpose selection of OOC models towards either simple but powerful testbeds for therapeutic development, or complex vasculature to accurately replicate human physiology for specific disease modeling and tissue regeneration.


Asunto(s)
Vasos Sanguíneos/fisiología , Animales , Biología/métodos , Regeneración Tisular Dirigida/métodos , Humanos , Dispositivos Laboratorio en un Chip
10.
J Spec Oper Med ; 21(1): 87-89, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33721312

RESUMEN

Ultrasonography is currently the primary means of imaging for forward surgical teams/forward resuscitative surgical teams (FSTs/FRSTs). As FSTs/FRSTs are pushed farther forward into more austere environments, access to other imaging modalities may be limited, potentially affecting resources. On a recent deployment, the 126th FRST was able to use radiography equipment from a co-located explosive ordnance disposal (EOD) team to assist in the diagnosis and treatment of medical and surgical patients, thereby saving time and resources. We provide three case examples in which using EOD radiography assisted in clinical decision making. Although the safety profile has not been assessed for clinical use in humans, EOD radiography can be a useful technique to aid in time-sensitive decision making in resource-constrained operational areas.


Asunto(s)
Sustancias Explosivas , Humanos , Radiografía , Resucitación , Ultrasonografía
11.
Adv Healthc Mater ; 10(10): e2100031, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33586357

RESUMEN

Engineering functional human tissues in vitro is currently limited by difficulty replicating the small caliber, complex connectivity, cellularity, and 3D curvature of the native microvasculature. Multiphoton ablation has emerged as a promising technique for fabrication of microvascular structures with high resolution and full 3D control, but cellularization and perfusion of complex capillary-scale structures has remained challenging. Here, multiphoton ablation combined with guided endothelial cell growth from pre-formed microvessels is used to successfully create perfusable and cellularized organ-specific microvascular structures at anatomic scale within collagen hydrogels. Fabrication and perfusion of model 3D pulmonary and renal microvascular beds is demonstrated, as is replication and perfusion of a brain microvascular unit derived from in vivo data. Successful endothelialization and blood perfusion of a kidney-specific microvascular structure is achieved, using laser-guided angiogenesis. Finally, proof-of-concept hierarchical blood vessels and complex multicellular models are created, using multistep patterning with multiphoton ablation techniques. These successes open new doors for the creation of engineered tissues and organ-on-a-chip devices.


Asunto(s)
Técnicas de Ablación , Microvasos , Células Endoteliales , Humanos , Perfusión , Ingeniería de Tejidos , Venas
12.
Trends Parasitol ; 37(5): 401-413, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33485788

RESUMEN

Plasmodium falciparum pathogenesis is complex and intimately connected to vascular physiology. This is exemplified by cerebral malaria (CM), a neurovascular complication that accounts for most of the malaria deaths worldwide. P. falciparum sequestration in the brain microvasculature is a hallmark of CM and is not replicated in animal models. Numerous aspects of the disease are challenging to fully understand from clinical studies, such as parasite binding tropism or causal pathways in blood-brain barrier breakdown. Recent bioengineering approaches allow for the generation of 3D microvessels and organ-specific vasculature that provide precise control of vessel architecture and flow dynamics, and hold great promise for malaria research. Here, we discuss recent and future applications of bioengineered microvessels in malaria pathogenesis research.


Asunto(s)
Bioingeniería , Microvasos , Parasitología , Plasmodium falciparum , Animales , Bioingeniería/tendencias , Encéfalo/parasitología , Humanos , Microvasos/química , Microvasos/parasitología , Parasitología/métodos , Plasmodium falciparum/fisiología
13.
Lasers Surg Med ; 52(10): 993-1009, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32311117

RESUMEN

BACKGROUND AND OBJECTIVES: To determine the efficacy of targeted fluorescent biomarkers and multiphoton imaging to characterize early changes in ovarian tissue with the onset of cancer. STUDY DESIGN/MATERIALS AND METHODS: A transgenic TgMISIIR-TAg mouse was used as an animal model for ovarian cancer. Mice were injected with fluorescent dyes to bind to the folate receptor α, matrix metalloproteinases, and integrins. Half of the mice were treated with 4-vinylcyclohexene diepoxide (VCD) to simulate menopause. Widefield fluorescence imaging (WFI) and multiphoton imaging of the ovaries and oviducts were conducted at 4 and 8 weeks of age. The fluorescence signal magnitude was quantified, and texture features were derived from multiphoton imaging. Linear discriminant analysis was then used to classify mouse groups. RESULTS: Imaging features from both fluorescence imaging and multiphoton imaging show significant changes (P < 0.01) with age, VCD treatment, and genotype. The classification model is able to classify different groups to accuracies of 75.53%, 69.53%, and 86.76%, for age, VCD treatment, and genotype, respectively. Building a classification model using features from multiple modalities shows marked improvement over individual modalities. CONCLUSIONS: This study demonstrates that using WFI with targeted biomarkers, and multiphoton imaging with endogenous contrast shows promise for detecting early changes in ovarian tissue with the onset of cancer. The results indicate that multimodal imaging can provide higher sensitivity for classifying tissue types than using single modalities alone. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.


Asunto(s)
Neoplasias Ováricas , Posmenopausia , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Imagen Óptica , Neoplasias Ováricas/diagnóstico por imagen
14.
Sci Adv ; 6(3): eaay7243, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-32010773

RESUMEN

Microcirculatory obstruction is a hallmark of severe malaria, but mechanisms of parasite sequestration are only partially understood. Here, we developed a robust three-dimensional microvessel model that mimics the arteriole-capillary-venule (ACV) transition consisting of a narrow 5- to 10-µm-diameter capillary region flanked by arteriole- or venule-sized vessels. Using this platform, we investigated red blood cell (RBC) transit at the single cell and at physiological hematocrits. We showed normal RBCs deformed via in vivo-like stretching and tumbling with negligible interactions with the vessel wall. By comparison, Plasmodium falciparum-infected RBCs exhibited virtually no deformation and rapidly accumulated in the capillary-sized region. Comparison of wild-type parasites to those lacking either cytoadhesion ligands or membrane-stiffening knobs showed highly distinctive spatial and temporal kinetics of accumulation, linked to velocity transition in ACVs. Our findings shed light on mechanisms of microcirculatory obstruction in malaria and establish a new platform to study hematologic and microvascular diseases.


Asunto(s)
Fenómenos Biofísicos , Eritrocitos/parasitología , Malaria/parasitología , Plasmodium falciparum/fisiología , Ingeniería de Tejidos , Capilares , Adhesión Celular , Movimiento Celular , Colágeno/metabolismo , Hematócrito , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Ligandos , Luz , Perfusión
15.
J Biomed Opt ; 24(9): 1-16, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31571434

RESUMEN

Ovarian cancer is the deadliest gynecologic cancer due predominantly to late diagnosis. Early detection of ovarian cancer can increase 5-year survival rates from 40% up to 92%, yet no reliable early detection techniques exist. Multiphoton microscopy (MPM) is a relatively new imaging technique sensitive to endogenous fluorophores, which has tremendous potential for clinical diagnosis, though it is limited in its application to the ovaries. Wide-field fluorescence imaging (WFI) has been proposed as a complementary technique to MPM, as it offers high-resolution imagery of the entire organ and can be tailored to target specific biomarkers that are not captured by MPM imaging. We applied texture analysis to MPM images of a mouse model of ovarian cancer. We also conducted WFI targeting the folate receptor and matrix metalloproteinases. We find that texture analysis of MPM images of the ovary can differentiate between genotypes, which is a proxy for disease, with high statistical significance (p < 0.001). The wide-field fluorescence signal also changes significantly between genotypes (p < 0.01). We use the features to classify multiple tissue groups to over 80% accuracy. These results suggest that MPM and WFI are promising techniques for the early detection of ovarian cancer.


Asunto(s)
Detección Precoz del Cáncer/métodos , Interpretación de Imagen Asistida por Computador/métodos , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Imagen Óptica/métodos , Neoplasias Ováricas/diagnóstico por imagen , Algoritmos , Animales , Modelos Animales de Enfermedad , Femenino , Ratones , Ovario/diagnóstico por imagen
16.
mBio ; 10(3)2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31138740

RESUMEN

Cerebral malaria is a severe neurological complication associated with sequestration of Plasmodium falciparum-infected erythrocytes (IE) in the brain microvasculature, but the specific binding interactions remain under debate. Here, we have generated an engineered three-dimensional (3D) human brain endothelial microvessel model and studied P. falciparum binding under the large range of physiological flow velocities that occur in both health and disease. Perfusion assays on 3D microvessels reveal previously unappreciated phenotypic heterogeneity in parasite binding to tumor necrosis factor alpha (TNF-α)-activated brain endothelial cells. While clonal parasite lines expressing a group B P. falciparum erythrocyte membrane protein 1 (PfEMP1) present an increase in binding to activated 3D microvessels, P. falciparum-IE expressing DC8-PfEMP1 present a decrease in binding. The differential response to endothelium activation is mediated by surface expression changes of endothelial protein C receptor (EPCR) and intercellular adhesion molecule 1 (ICAM-1). These findings demonstrate heterogeneity in parasite binding and provide evidence for a parasite strategy to adapt to a changing microvascular environment during infection. The engineered 3D human brain microvessel model provides new mechanistic insight into parasite binding and opens opportunities for further studies on malaria pathogenesis and parasite-vessel interactions.IMPORTANCE Cerebral malaria research has been hindered by the inaccessibility of the brain. Here, we have developed an engineered 3D human brain microvessel model that mimics the blood flow rates and architecture of small blood vessels to study how P. falciparum-infected human erythrocytes attach to brain endothelial cells. By studying parasite lines with different adhesive properties, we show that the malaria parasite binding rate is heterogeneous and strongly influenced by physiological differences in flow and whether the endothelium has been previously activated by TNF-α, a proinflammatory cytokine that is linked to malaria disease severity. We also show the importance of human EPCR and ICAM-1 in parasite binding. Our model sheds new light on how P. falciparum binds within brain microvessels and provides a powerful method for future investigations of recruitment of human brain pathogens to the blood vessel lining of the brain.


Asunto(s)
Encéfalo/parasitología , Adhesión Celular , Receptor de Proteína C Endotelial/metabolismo , Eritrocitos/parasitología , Molécula 1 de Adhesión Intercelular/metabolismo , Microvasos/parasitología , Plasmodium falciparum/fisiología , Sitios de Unión , Encéfalo/citología , Técnicas de Cultivo de Célula , Células Cultivadas , Células Endoteliales/parasitología , Receptor de Proteína C Endotelial/genética , Eritrocitos/fisiología , Humanos , Molécula 1 de Adhesión Intercelular/genética , Malaria Cerebral/parasitología , Malaria Cerebral/fisiopatología , Malaria Falciparum/parasitología , Microvasos/citología , Proteínas Protozoarias/metabolismo , Receptores de Superficie Celular/metabolismo , Ingeniería de Tejidos/métodos , Factor de Necrosis Tumoral alfa/inmunología
17.
Comp Med ; 69(1): 16-21, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30591091

RESUMEN

Transgenic TgMISIIR-TAg (TAg) mice express the oncogenic virus SV40 in Mullerian epithelial cells. Female TAg mice spontaneously develop epithelial ovarian carcinoma, the most common type of ovarian cancer in women. Female TAg mice are infertile, but the reason has not been determined. We therefore investigated whether female TAg mice undergo puberty, demonstrate follicular development, maintain regular cycles, and ovulate. Ovarian cancers in women commonly develop after menopause. The occupational chemical 4-vinylcyclohexene diepoxide (VCD) accelerates follicle degeneration in the ovaries of rats and mice, causing early ovarian failure. We therefore used VCD dosing of mice to develop an animal model for menopause. The purpose of this study was to characterize reproductive parameters in female TAg mice and to investigate whether the onset of ovarian failure due VCD dosing differed between female TAg and WT C57BL/6 mice. As in WT female mice, TAg female mice underwent puberty (vaginal opening) and developed cyclicity in patterns that were similar between the groups. Vehicle-only TAg mice had fewer ovulations (numbers of corpora lutea) than WT animals. VCD exposure delayed the onset of puberty (day of first estrus) in TAg as compared with WT mice. Morphologic evaluation of ovaries revealed many more degenerating follicles in TAg mice than WT mice, and more VCD-dosed TAg mice were in ovarian failure than VCD-dosed WT mice. These results suggest that despite showing similar onset of sexual maturation, TAg mice have increased follicular degeneration and fewer ovulations than WT. These features may contribute to the inability of female TAg mice to reproduce.


Asunto(s)
Variantes Farmacogenómicas , Reproducción/efectos de los fármacos , Reproducción/genética , Animales , Ciclohexenos/toxicidad , Estro/efectos de los fármacos , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Folículo Ovárico/efectos de los fármacos , Compuestos de Vinilo/toxicidad
18.
J Bone Joint Surg Am ; 94(17): 1605-9, 2012 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-22992851

RESUMEN

BACKGROUND: C5 nerve palsy is a known complication of cervical spine surgery. The development and etiology of this complication are not completely understood. The purpose of the present study was to determine whether rotation of the cervical spinal cord predicts the development of a C5 palsy. METHODS: We performed a retrospective review of prospectively collected spine registry data as well as magnetic resonance images. We reviewed the records for 176 patients with degenerative disorders of the cervical spine who underwent anterior cervical decompression or corpectomy within the C4 to C6 levels. Our measurements included area for the spinal cord, space available for the cord, and rotation of the cord with respect to the vertebral body. RESULTS: There was a 6.8% prevalence of postoperative C5 nerve palsy as defined by deltoid motor strength of ≤ 3 of 5. The average rotation of the spinal cord (and standard deviation) was 2.8° ± 3.0°. A significant association was detected between the degree of rotation (0° to 5° versus 6° to 10° versus ≥ 11°) and palsy (point-biserial correlation = 0.94; p < 0.001). A diagnostic criterion of 6° of rotation could identify patients who had a C5 palsy (sensitivity = 1.00 [95% confidence interval, 0.70 to 1.00], specificity = 0.97 [95% confidence interval, 0.93 to 0.99], positive predictive value = 0.71 [95% confidence interval, 0.44 to 0.89], negative predictive value = 1.00 [95% confidence interval, 0.97 to 1.00]). CONCLUSIONS: Our evidence suggests that spinal cord rotation is a strong and significant predictor of C5 palsy postoperatively. Patients can be classified into three types, with Type 1 representing mild rotation (0° to 5°), Type 2 representing moderate rotation (6° to 10°), and Type 3 representing severe rotation (≥ 11°). The rate of C5 palsy was zero of 159 in the Type-1 group, eight of thirteen in the Type-2 group, and four of four in the Type-3 group. This information may be valuable for surgeons and patients considering anterior surgery in the C4 to C6 levels.


Asunto(s)
Neuropatías del Plexo Braquial/etiología , Vértebras Cervicales/cirugía , Descompresión Quirúrgica/efectos adversos , Médula Espinal/fisiopatología , Estenosis Espinal/cirugía , Adulto , Anciano , Neuropatías del Plexo Braquial/fisiopatología , Vértebras Cervicales/patología , Estudios de Cohortes , Descompresión Quirúrgica/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Parálisis/etiología , Parálisis/fisiopatología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/métodos , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Rotación , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Raíces Nerviosas Espinales/fisiopatología , Estenosis Espinal/diagnóstico , Resultado del Tratamiento , Adulto Joven
19.
Am J Trop Med Hyg ; 77(4): 623-6, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17978060

RESUMEN

The pathogenesis of malarial anemia is incompletely understood. Hepcidin, a recently discovered peptide hormone, is a major regulator of iron metabolism and is thought to play a central role in the anemia of chronic inflammation. The specific aim of the study was to characterize the association between urinary hepcidin, hemoglobin, and parasitemia in 199 patients presenting for evaluation of Plasmodium falciparum malaria in Ghana. Urinary hepcidin was semi-quantitatively assessed using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. Urinary hepcidin (intensity/mmol creatinine) was associated with log parasitemia in 86 children (beta = 0.086, standard error [SE] = 0.035, P < 0.017), 31 pregnant women (beta = 0.218, SE = 0.085, P < 0.016), and 82 adults (beta = 0.184, SE =0.043, P < 0.0001). Urinary hepcidin was not significantly associated with hemoglobin or anemia. Urinary hepcidin is more strongly associated with parasitemia than hemoglobin or anemia among patients with acute P. falciparum malaria in Ghana.


Asunto(s)
Anemia/orina , Péptidos Catiónicos Antimicrobianos/orina , Malaria Falciparum/orina , Adolescente , Adulto , Anemia/sangre , Niño , Preescolar , Femenino , Ghana , Hemoglobinas/metabolismo , Hepcidinas , Humanos , Hierro/metabolismo , Malaria Falciparum/sangre , Malaria Falciparum/parasitología , Masculino , Espectrometría de Masas/métodos , Parasitemia/sangre , Parasitemia/orina , Embarazo
20.
J Trop Pediatr ; 53(4): 238-44, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17463011

RESUMEN

The high incidence of anemia of infection among children in developing countries is not well characterized. We investigated the relationship between diarrhea, fever and other risk factors for anemia in young children in the community. The relationship between risk factors for anemia was examined in a cross-sectional study of 85 229 children, aged 6-59 months, from impoverished families in rural areas of Indonesia. The prevalence of anemia was 56.1% among the study subjects. Those considered anemic were more likely to be younger, male, stunted, underweight, wasted, to have low maternal and paternal education and to have current diarrhea or history of diarrhea in the previous 7 days compared with children without anemia (all P < 0.0001). In separate multivariate models adjusted for age, sex, stunting, maternal age and education, and weekly per capita household expenditure, current diarrhea (OR 1.15, 95% CI 1.07-1.325, P < 0.0001) and a history of diarrhea in the previous 7 days (OR 1.16, 95% CI 1.09-1.25, P < 0.0001) were associated with an increased risk of anemia. In similar models, current fever had a borderline association with anemia (OR 1.14, 95% CI 0.98-1.32, P = 0.09). We conclude that diarrhea is a contributing factor of anemia among young children living in rural areas in Indonesia.


Asunto(s)
Anemia/epidemiología , Diarrea/epidemiología , Salud Rural , Anemia/etiología , Preescolar , Estudios Transversales , Diarrea/complicaciones , Escolaridad , Femenino , Fiebre/epidemiología , Humanos , Incidencia , Indonesia/epidemiología , Lactante , Modelos Logísticos , Masculino , Áreas de Pobreza , Factores de Riesgo
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