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1.
J Immunol ; 202(1): 151-159, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30530595

RESUMEN

The FcγRs are immune cell surface proteins that bind IgG and facilitate cytokine production, phagocytosis, and Ab-dependent, cell-mediated cytotoxicity. FcγRs play a critical role in immunity; variation in these genes is implicated in autoimmunity and other diseases. Cynomolgus macaques are an excellent animal model for many human diseases, and Mauritian cynomolgus macaques (MCMs) are particularly useful because of their restricted genetic diversity. Previous studies of MCM immune gene diversity have focused on the MHC and killer cell Ig-like receptor. In this study, we characterize FcγR diversity in 48 MCMs using PacBio long-read sequencing to identify novel alleles of each of the four expressed MCM FcγR genes. We also developed a high-throughput FcγR genotyping assay, which we used to determine allele frequencies and identify FcγR haplotypes in more than 500 additional MCMs. We found three alleles for FcγR1A, seven each for FcγR2A and FcγR2B, and four for FcγR3A; these segregate into eight haplotypes. We also assessed whether different FcγR alleles confer different Ab-binding affinities by surface plasmon resonance and found minimal difference in binding affinities across alleles for a panel of wild type and Fc-engineered human IgG. This work suggests that although MCMs may not fully represent the diversity of FcγR responses in humans, they may offer highly reproducible results for mAb therapy and toxicity studies.


Asunto(s)
Genotipo , Macaca fascicularis , Receptores de IgG/genética , Alelos , Animales , Citotoxicidad Celular Dependiente de Anticuerpos , Frecuencia de los Genes , Haplotipos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunidad , Inmunoglobulina G/metabolismo , Modelos Animales , Unión Proteica/genética , Receptores de IgG/metabolismo
2.
PLoS Pathog ; 13(5): e1006378, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28542585

RESUMEN

Infection with Zika virus (ZIKV) is associated with human congenital fetal anomalies. To model fetal outcomes in nonhuman primates, we administered Asian-lineage ZIKV subcutaneously to four pregnant rhesus macaques. While non-pregnant animals in a previous study contemporary with the current report clear viremia within 10-12 days, maternal viremia was prolonged in 3 of 4 pregnancies. Fetal head growth velocity in the last month of gestation determined by ultrasound assessment of head circumference was decreased in comparison with biparietal diameter and femur length within each fetus, both within normal range. ZIKV RNA was detected in tissues from all four fetuses at term cesarean section. In all pregnancies, neutrophilic infiltration was present at the maternal-fetal interface (decidua, placenta, fetal membranes), in various fetal tissues, and in fetal retina, choroid, and optic nerve (first trimester infection only). Consistent vertical transmission in this primate model may provide a platform to assess risk factors and test therapeutic interventions for interruption of fetal infection. The results may also suggest that maternal-fetal ZIKV transmission in human pregnancy may be more frequent than currently appreciated.


Asunto(s)
Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Infecciosas del Embarazo , Infección por el Virus Zika/transmisión , Virus Zika/fisiología , Líquido Amniótico/virología , Animales , Decidua/patología , Decidua/virología , Modelos Animales de Enfermedad , Femenino , Desarrollo Fetal , Feto , Humanos , Pulmón/patología , Pulmón/virología , Macaca mulatta , Placenta/patología , Placenta/virología , Embarazo , ARN Viral/análisis , Bazo/patología , Bazo/virología , Cordón Umbilical/patología , Cordón Umbilical/virología , Viremia , Infección por el Virus Zika/patología , Infección por el Virus Zika/virología
3.
Immunogenetics ; 70(6): 381-399, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29134258

RESUMEN

Pig-tailed macaques (Macaca nemestrina, Mane) are important models for human immunodeficiency virus (HIV) studies. Their infectability with minimally modified HIV makes them a uniquely valuable animal model to mimic human infection with HIV and progression to acquired immunodeficiency syndrome (AIDS). However, variation in the pig-tailed macaque major histocompatibility complex (MHC) and the impact of individual transcripts on the pathogenesis of HIV and other infectious diseases is understudied compared to that of rhesus and cynomolgus macaques. In this study, we used Pacific Biosciences single-molecule real-time circular consensus sequencing to describe full-length MHC class I (MHC-I) transcripts for 194 pig-tailed macaques from three breeding centers. We then used the full-length sequences to infer Mane-A and Mane-B haplotypes containing groups of MHC-I transcripts that co-segregate due to physical linkage. In total, we characterized full-length open reading frames (ORFs) for 313 Mane-A, Mane-B, and Mane-I sequences that defined 86 Mane-A and 106 Mane-B MHC-I haplotypes. Pacific Biosciences technology allows us to resolve these Mane-A and Mane-B haplotypes to the level of synonymous allelic variants. The newly defined haplotypes and transcript sequences containing full-length ORFs provide an important resource for infectious disease researchers as certain MHC haplotypes have been shown to provide exceptional control of simian immunodeficiency virus (SIV) replication and prevention of AIDS-like disease in nonhuman primates. The increased allelic resolution provided by Pacific Biosciences sequencing also benefits transplant research by allowing researchers to more specifically match haplotypes between donors and recipients to the level of nonsynonymous allelic variation, thus reducing the risk of graft-versus-host disease.


Asunto(s)
Genes MHC Clase I/genética , Macaca nemestrina/genética , Macaca nemestrina/inmunología , Alelos , Secuencia de Aminoácidos , Animales , Clonación Molecular/métodos , VIH , Haplotipos/inmunología , Antígenos de Histocompatibilidad/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Complejo Mayor de Histocompatibilidad/inmunología , Virus de la Inmunodeficiencia de los Simios
4.
Immunogenetics ; 69(4): 211-229, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28078358

RESUMEN

Very little is currently known about the major histocompatibility complex (MHC) region of cynomolgus macaques (Macaca fascicularis; Mafa) from Chinese breeding centers. We performed comprehensive MHC class I haplotype analysis of 100 cynomolgus macaques from two different centers, with animals from different reported original geographic origins (Vietnamese, Cambodian, and Cambodian/Indonesian mixed-origin). Many of the samples were of known relation to each other (sire, dam, and progeny sets), making it possible to characterize lineage-level haplotypes in these animals. We identified 52 Mafa-A and 74 Mafa-B haplotypes in this cohort, many of which were restricted to specific sample origins. We also characterized full-length MHC class I transcripts using Pacific Biosciences (PacBio) RS II single-molecule real-time (SMRT) sequencing. This technology allows for complete read-through of unfragmented MHC class I transcripts (~1100 bp in length), so no assembly is required to unambiguously resolve novel full-length sequences. Overall, we identified 311 total full-length transcripts in a subset of 72 cynomolgus macaques from these Chinese breeding facilities; 130 of these sequences were novel and an additional 115 extended existing short database sequences to span the complete open reading frame. This significantly expands the number of Mafa-A, Mafa-B, and Mafa-I full-length alleles in the official cynomolgus macaque MHC class I database. The PacBio technique described here represents a general method for full-length allele discovery and genotyping that can be extended to other complex immune loci such as MHC class II, killer immunoglobulin-like receptors, and Fc gamma receptors.


Asunto(s)
Haplotipos/genética , Macaca fascicularis/genética , Complejo Mayor de Histocompatibilidad/genética , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN/métodos , Alelos , Animales , Cruzamiento , China , Frecuencia de los Genes , Genotipo
5.
Immunogenetics ; 69(5): 325-339, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28343239

RESUMEN

Killer cell immunoglobulin-like receptors (KIRs) modulate disease progression of pathogens including HIV, malaria, and hepatitis C. Cynomolgus and rhesus macaques are widely used as nonhuman primate models to study human pathogens, and so, considerable effort has been put into characterizing their KIR genetics. However, previous studies have relied on cDNA cloning and Sanger sequencing that lack the throughput of current sequencing platforms. In this study, we present a high throughput, full-length allele discovery method utilizing Pacific Biosciences circular consensus sequencing (CCS). We also describe a new approach to Macaque Exome Sequencing (MES) and the development of the Rhexome1.0, an adapted target capture reagent that includes macaque-specific capture probe sets. By using sequence reads generated by whole genome sequencing (WGS) and MES to inform primer design, we were able to increase the sensitivity of KIR allele discovery. We demonstrate this increased sensitivity by defining nine novel alleles within a cohort of Mauritian cynomolgus macaques (MCM), a geographically isolated population with restricted KIR genetics that was thought to be completely characterized. Finally, we describe an approach to genotyping KIRs directly from sequence reads generated using WGS/MES reads. The findings presented here expand our understanding of KIR genetics in MCM by associating new genes with all eight KIR haplotypes and demonstrating the existence of at least one KIR3DS gene associated with every haplotype.


Asunto(s)
Exoma , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Macaca fascicularis/genética , Receptores KIR/genética , Animales , Frecuencia de los Genes , Macaca fascicularis/inmunología , Análisis de Secuencia de ADN/métodos
6.
J Foot Ankle Surg ; 55(3): 444-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26884262

RESUMEN

First metatarsocuneiform joint arthrodesis with a locking bone plate and screw system has been effectively used to correct metatarsus primus varus and instability of the first ray. The goal of the present cadaveric biomechanical study was to quantify and compare the inherent strength of the first metatarsocuneiform joint and surrounding bones fixated with the osteo-WEDGE(™) bone plate locking system (OW) with that of intact specimens. Fourteen fresh-frozen adult human cadaveric foot specimens consisting of the first metatarsal and medial cuneiform bones with intact joint capsules and ligaments were used. The OW was implanted in 7 of these specimens at the first metatarsal cuneiform joint (MCJ), and the remaining 7 specimens were left intact. Each of the specimens was then subjected to axial force to simulate dorsiflexion of the first metatarsal using a cantilever bending test setup. Load was applied on the plantar aspect of the first metatarsal head until failure of the construct. The mean load and bending moment on the first MCJ at failure for the implanted specimens were 119.98 ± 56.76 N and 5.57 ± 2.71 Nm, respectively. For the intact specimens, the mean load and bending moment on the first MCJ at failure were 107.93 ± 60.90 N and 6.07 ± 3.18 Nm, respectively. None of the specimens showed catastrophic failure within the physiologic loading limits. These results imply that the mechanical strength of the OW is comparable to that of intact specimens. Thus, the first MCJ and surrounding bones fixated with an OW should be able to effectively withstand the vertical ground reaction forces the same as intact specimens.


Asunto(s)
Artrodesis/instrumentación , Placas Óseas , Hallux Valgus/cirugía , Articulaciones Tarsianas/cirugía , Adulto , Artrodesis/métodos , Fenómenos Biomecánicos , Humanos , Huesos Metatarsianos/cirugía , Diseño de Prótesis , Huesos Tarsianos/cirugía
7.
Am J Bot ; 99(9): 1541-52, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22947483

RESUMEN

PREMISE OF THE STUDY: The filamentous chlorophyte Cladophora produces abundant nearshore populations in marine and freshwaters worldwide, often dominating periphyton communities and producing nuisance growths under eutrophic conditions. High surface area and environmental persistence foster such high functional and taxonomic diversity of epiphytic microfauna and microalgae that Cladophora has been labeled an ecological engineer. We tested the hypotheses that (1) Cladophora supports a structurally and functionally diverse epiphytic prokaryotic microbiota that influences materials cycling and (2) mutualistic host-microbe interactions occur. Because previous molecular sequencing-based analyses of the microbiota of C. glomerata found as western Lake Michigan beach drift had identified pathogenic associates such as Escherichia coli, we also asked if actively growing lentic C. glomerata harbors known pathogens. METHODS: We used 16S rRNA gene amplicon pyrosequencing to examine the microbiota of C. glomerata of Lake Mendota, Dane, Wisconsin, United States, during the growing season of 2011, at the genus- or species-level to infer functional phenotypes. We used correlative scanning electron and fluorescence microscopy to describe major prokaryotic morphotypes. KEY RESULTS: We found microscopic evidence for diverse bacterial morphotypes, and molecular evidence for ca. 100 distinct sequence types classifiable to genus at the 80% confidence level or species at the 96-97% level within nine bacterial phyla, but not E. coli or related human pathogens. CONCLUSIONS: We inferred that bacterial epiphytes of lentic C. glomerata have diverse functions in materials cycling, with traits that indicate the occurrence of mutualistic interactions with the algal host.


Asunto(s)
Chlorophyta/microbiología , Metagenoma/genética , Algas Marinas/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/ultraestructura , Secuencia de Bases , Genotipo , Filogenia , ARN Ribosómico 16S/genética , Wisconsin
8.
J Foot Ankle Surg ; 51(1): 23-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22196455

RESUMEN

The purpose of this retrospective study was to determine long-term functional outcomes and device tolerance achieved in adult patients who chose to undergo an extraosseous talotarsal stabilization procedure HyProCure(®) for the treatment of flexible talotarsal joint deformity. Eighty-three adult patients participated in this study. Postoperative subjective assessment of device performance was evaluated using Maryland Foot Scores, which were collected at a mean follow-up period of 51 months. The mean postoperative Maryland Foot Score was 88 out of 100; postoperatively, 52% of cases reported complete alleviation of foot pain, 69% of cases had no limitations on their foot functional abilities, and 80% of cases reported complete satisfaction with the appearance of their feet. The implant was removed in 7 out of 117 cases (removal rate: 6%) due to prolonged pain of the anterior talofibular ligament (4 cases), psychogenic reaction (2 cases), and postoperative infection (1 case). The long-term positive subjective outcomes and excellent patient satisfaction obtained in this study may imply that extraosseous talotarsal stabilization was effective in stabilizing the talotarsal joint complex and eliminating excessive abnormal pronation, thus reducing pain and improving quality of life of the patients; it represents a possible treatment option for partial talotarsal dislocation in cases with flexible and reducible deformity.


Asunto(s)
Inestabilidad de la Articulación/cirugía , Prótesis e Implantes , Articulaciones Tarsianas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Artralgia/cirugía , Femenino , Estudios de Seguimiento , Humanos , Luxaciones Articulares/cirugía , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
9.
J Foot Ankle Surg ; 51(5): 613-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22789481

RESUMEN

Displacement of the articular facets of talus on the tarsal mechanism, or partial talotarsal dislocation, is a condition seen in children, adult, and geriatric populations. A characteristic of this pathologic condition is a prolonged period of and excessive amount of pronation (hyperpronation) on weightbearing. The ill effects of this condition may lead to a multitude of other foot pathologies and to pathologies associated with the proximal lower extremity musculoskeletal structures. A variety of conservative and operative treatment options have been used to eliminate or minimize hyperpronation. Extraosseous talotarsal stabilization (EOTTS) devices have been used to realign and stabilize the articular facets of the talus on the tarsal mechanism, thereby attempting to restore the normal range of hindfoot motion while eliminating hyperpronation. A multitude of such devices, which are intended for the same purpose, are available for the surgeon to choose from. However, there is no literature discussing the differences among these devices, or the benefits of one device over the other. Based on current understanding and available knowledge base, the goal of this article was to classify EOTTS devices based on their design features and biomechanical functioning. A theoretical description of how these different types of devices function is laid out in an attempt to understand the reason for their success or failure. This new classification system is intended to help researchers and surgeons appreciate the subtle yet important differences among these devices, and to thus help them design future research studies when using these devices.


Asunto(s)
Luxaciones Articulares/cirugía , Inestabilidad de la Articulación/cirugía , Astrágalo/fisiopatología , Articulaciones Tarsianas , Fenómenos Biomecánicos , Humanos , Equipo Ortopédico , Estrés Mecánico , Huesos Tarsianos/fisiopatología , Articulaciones Tarsianas/fisiopatología
10.
J Foot Ankle Surg ; 51(5): 548-55, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22795448

RESUMEN

The purpose of this study was to determine radiographic correction achieved in adult patients treated with an extraosseous talotarsal stabilization (EOTTS) procedure. Patients diagnosed with flexible/reducible talotarsal joint dislocation (partial) underwent surgical correction with the HyProCure(®) EOTTS device. Preoperative and postoperative weightbearing radiographs taken in the anteroposterior (AP) and lateral views for a total 95 feet (in 70 patients) were analyzed to determine standardized radiographic angles, and to quantify the correction obtained after the EOTTS procedure. Postoperative radiographs were taken at an average follow-up of 17 days from the surgery date. The mean preoperative and postoperative talar second metatarsal angles (measured from the AP radiographs) were 24.8° ± 1.0° and 5.8° ± 0.9°, respectively, that is, mean decrease by 19°. The mean preoperative and postoperative talar declination angles (measured from the lateral radiographs) were 25.1° ± 0.7° and 19.4° ± 0.5°, respectively, that is, mean decrease by 5.7°. The mean preoperative and postoperative calcaneal inclination angles (measured from the lateral radiographs) were 21° ± 0.7° and 21.8° ± 0.7°, respectively, that is, mean increase by 0.8°. Postoperatively, the talar second metatarsal and talar declination angles were reduced to average values reported in the literature for normal feet. This study shows the efficacy of a minimally invasive EOTTS procedure in restoring the normal angular relationships between hindfoot and forefoot osseous structures on weightbearing, in both the transverse and sagittal planes. This indicates stabilization of the talotarsal joint complex and elimination of hyperpronation, which may lead to reduced pain, improved foot functional abilities, and patient satisfaction.


Asunto(s)
Luxaciones Articulares/diagnóstico por imagen , Astrágalo/diagnóstico por imagen , Articulaciones Tarsianas/diagnóstico por imagen , Articulaciones Tarsianas/lesiones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Luxaciones Articulares/cirugía , Masculino , Persona de Mediana Edad , Pronación , Radiografía , Rango del Movimiento Articular , Astrágalo/cirugía , Articulaciones Tarsianas/cirugía , Soporte de Peso , Adulto Joven
12.
J Foot Ankle Surg ; 50(5): 551-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21683621

RESUMEN

The navicular drop in the sagittal plane on weight-bearing is a valid indicator of foot pronation. Dislocation of the talus on the tarsal mechanism results in hyperpronation, which can lead to excessive navicular drop. The purpose of the present study was to radiographically determine the efficacy of HyProCure(®) in realigning the navicular bone in hyperpronating feet. We hypothesized that following the placement of HyProCure(®), the navicular height would increase significantly compared to its preoperative value. Radiographs of 61 adult patients (86 feet) who received HyProCure(®) without adjunctive hindfoot or midfoot soft tissue or osseous procedures were analyzed. The distance of the navicular with respect to the cuboid was measured from the pre- and postoperative weight-bearing lateral radiographs. Additionally, we measured foot length to normalize the navicular to cuboid distance. The postoperative radiographs were taken at an average follow-up of 17 days. The mean preoperative true navicular to cuboid distance was 19 ± 6 mm as compared to a mean postoperative value of 24 ± 5 mm. The mean pre- and postoperative normalized navicular to cuboid distances were 0.098 ± 0.029 and 0.125 ± 0.027, respectively (± 1 SD). The postoperative increase in the true and normalized navicular to cuboid distance was statistically significant (p < .001). HyProCure(®) was effective in improving the anatomic alignment of the talonavicular joint by reducing excessive navicular drop. This indicates reduction of excessive abnormal pronation and stabilization of the medial column of the foot, which can also lead to reduction in the excessive forces placed on the supporting soft tissue structures.


Asunto(s)
Inestabilidad de la Articulación/cirugía , Pronación/fisiología , Prótesis e Implantes , Huesos Tarsianos/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/fisiopatología , Luxaciones Articulares/cirugía , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/fisiopatología , Masculino , Persona de Mediana Edad , Radiografía , Huesos Tarsianos/fisiopatología , Articulaciones Tarsianas/diagnóstico por imagen , Articulaciones Tarsianas/fisiopatología , Articulaciones Tarsianas/cirugía , Adulto Joven
13.
J Foot Ankle Surg ; 50(1): 44-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21106413

RESUMEN

Tarsal tunnel syndrome is characterized by increased pressure in the tarsal tunnel. In hyperpronation, there is excessive abnormal pronation resulting from partial displacement of the talus on the calcaneus. In this study, we hypothesized that hyperpronation caused by talotarsal instability will lead to increased pressure in the tarsal tunnel and porta pedis. We also hypothesized that the pressure in these compartments will decrease following an extra-osseous talotarsal stabilization procedure using HyProCure(®). Pressures in the tarsal tunnel and porta pedis were measured in 9 fresh-frozen cadaver specimens using an intracompartmental pressure monitor system. Pressures were measured with the foot in neutral and hyperpronated position, before and after stabilization using HyProCure. For the tarsal tunnel, pressure in the neutral position with and without HyProCure was 3 ± 3 mm Hg and 4 ± 3 mm Hg, respectively (P = .159). However, for the hyperpronating foot, the pressure decreased from 32 ± 16 mm Hg to 21 ± 10 mm Hg (P < .001) following the placement of HyProCure. In the porta pedis, pressure in the neutral position with and without HyProCure was 2 ± 2 mm Hg and 2 ± 2 mm Hg, respectively (P = .168). However, for the hyperpronating foot, the pressure decreased from 29 ± 15 mm Hg to 18 ± 11 mm Hg (P < .001) following the placement of HyProCure. The pain caused by compression of the posterior tibial nerve in the tarsal tunnel and its branches in the porta pedis, owing to hyperpronation, may be alleviated by implantation of HyProCure.


Asunto(s)
Descompresión Quirúrgica/instrumentación , Stents , Síndrome del Túnel Tarsiano/cirugía , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Cadáver , Descompresión Quirúrgica/métodos , Femenino , Humanos , Presión , Pronación , Rango del Movimiento Articular/fisiología , Estadísticas no Paramétricas , Estrés Mecánico , Nervio Tibial/fisiopatología
14.
J Foot Ankle Surg ; 50(6): 682-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21920784

RESUMEN

Abnormal talotarsal joint mechanics leading to hyperpronation is implicated as one of the most common causes of plantar fasciopathy. In patients with hyperpronating feet, the plantar fascia experiences excessive tensile forces during static and dynamic weight-bearing activities because of excessive medial longitudinal arch depression. For the purposes of this study, we hypothesized that plantar fascia strain in hyperpronating cadaveric feet would decrease after intervention with an extra-osseous talotarsal stabilization (EOTTS) device. A miniature differential variable reluctance transducer was used to quantify the plantar fascia strain in 6 fresh-frozen cadaver foot specimens exhibiting flexible instability of the talotarsal joint complex (i.e., hyperpronation). The strain was measured as the foot was moved from its neutral to maximally pronated position, before and after intervention using the HyProCure(®) EOTTS device. The mean plantar fascia elongation was 0.83 ± 0.27 mm (strain 3.62% ± 1.17%) and 0.56 ± 0.2 mm (strain 2.42% ± 0.88%) before and after intervention, respectively (N = 18, variation reported is ± 1 SD). The average plantar fascia strain decreased by 33%, and the difference was statistically significant with p < .001. From this cadaveric experiment, the reduction in plantar fascia strain suggests that an EOTTS device might be effective in stabilizing the pathologic talotarsal joint complex and the medial longitudinal arch and in eliminating hyperpronation. An EOTTS procedure might offer a possible treatment option for plantar fasciopathy in cases in which the underlying etiology is abnormal talotarsal biomechanics.


Asunto(s)
Fascia/fisiopatología , Inestabilidad de la Articulación/cirugía , Procedimientos Ortopédicos/métodos , Esguinces y Distensiones/fisiopatología , Articulaciones Tarsianas/cirugía , Adulto , Fenómenos Biomecánicos , Cadáver , Fascitis Plantar/etiología , Fascitis Plantar/fisiopatología , Femenino , Pie/cirugía , Humanos , Inestabilidad de la Articulación/complicaciones , Inestabilidad de la Articulación/fisiopatología , Procedimientos Ortopédicos/efectos adversos , Pronación/fisiología , Rango del Movimiento Articular/fisiología , Esguinces y Distensiones/etiología , Estrés Mecánico
15.
J Foot Ankle Surg ; 50(6): 672-5, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21907596

RESUMEN

Excessive abnormal strain or tension on the posterior tibial nerve in feet exhibiting talotarsal instability has been considered one of the possible etiologic factors of tarsal tunnel syndrome. The suggested treatment options in such cases include stabilization of the talotarsal joint complex in a corrected position, which might help minimize the abnormal forces placed on the posterior tibial nerve due to over stretching. The primary goal of this study was to quantify strain on the posterior tibial nerve in feet exhibiting hyperpronation caused by talotarsal instability, before and after an extra-osseous talotarsal stabilization (EOTTS) procedure. We hypothesized that the excessive strain placed on the posterior tibial nerve in hyperpronating cadaveric feet would be reduced significantly after intervention using the HyProCure(®) EOTTS device. Posterior tibial nerve strain was quantified in 9 fresh-frozen cadaver specimens. A miniature differential variable reluctance transducer was used to measure nerve elongation as the foot was moved from its neutral to a maximally pronated position, before and after intervention. The mean elongation of the posterior tibial nerve (with respect to a fixed reference point) decreased by 43% after the EOTTS procedure (i.e., from 5.91 ± 0.91 mm to 3.38 ± 1.20 mm; N = 27). The reduction was statistically significant at p < .001. HyProCure(®) was effective in stabilizing the talotarsal joint complex, thus reducing the excessive amount of strain placed on the posterior tibial nerve. Clinical implications of this study suggest the use of EOTTS devices in the treatment of tarsal tunnel syndrome.


Asunto(s)
Inestabilidad de la Articulación/complicaciones , Inestabilidad de la Articulación/cirugía , Procedimientos de Cirugía Plástica/métodos , Articulaciones Tarsianas/cirugía , Síndrome del Túnel Tarsiano/etiología , Nervio Tibial/fisiopatología , Fenómenos Biomecánicos , Cadáver , Femenino , Humanos , Masculino , Pronación/fisiología , Rango del Movimiento Articular/fisiología , Sensibilidad y Especificidad , Esguinces y Distensiones/fisiopatología , Esguinces y Distensiones/cirugía , Estrés Mecánico , Articulaciones Tarsianas/fisiopatología , Síndrome del Túnel Tarsiano/fisiopatología , Síndrome del Túnel Tarsiano/prevención & control , Nervio Tibial/cirugía
16.
J Foot Ankle Surg ; 50(6): 676-81, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21908205

RESUMEN

Posterior tibial tendon dysfunction is considered one of the most common causes of progressive adult acquired flatfoot deformity. The etiology leading to the dysfunction of posterior tibial tendon remains controversial. The purpose of this study was to quantify strain on the posterior tibial tendon in cadaver feet exhibiting hyperpronation caused by flexible instability of the talotarsal joint complex. We hypothesized that posterior tibial tendon strain would decrease after a minimally invasive extra-osseous talotarsal stabilization procedure. A miniature differential variable reluctance transducer was used to measure the elongation of posterior tibial tendon in 9 fresh-frozen cadaver specimens. The elongation was measured as the foot was moved from its neutral to maximally pronated position, before and after intervention with the HyProCure(®) extra-osseous talotarsal stabilization device. The mean elongation of the posterior tibial tendon (with respect to a fixed reference point) was found to be 6.23 ± 2.07 mm and 3.04 ± 1.85 mm, before and after intervention, respectively (N = 27; variation is ± 1 SD). The average elongation reduced by 51% and was statistically significant with p < .001. Strain on the posterior tibial tendon is significantly higher in hyperpronating feet. An extra-osseous talotarsal stabilization procedure reduces excessive abnormal elongation of the posterior tibial tendon by minimizing excessive abnormal pronation. This minimally invasive procedure may thus provide a possible treatment option to prevent or cure posterior tibial tendon dysfunction in patients exhibiting flexible instability of the talotarsal joint complex.


Asunto(s)
Inestabilidad de la Articulación/cirugía , Procedimientos Ortopédicos/métodos , Disfunción del Tendón Tibial Posterior/cirugía , Rango del Movimiento Articular/fisiología , Adulto , Articulación del Tobillo/fisiopatología , Articulación del Tobillo/cirugía , Fenómenos Biomecánicos , Cadáver , Intervalos de Confianza , Femenino , Pie Plano/etiología , Pie Plano/cirugía , Humanos , Disfunción del Tendón Tibial Posterior/complicaciones , Pronación/fisiología , Esguinces y Distensiones , Estrés Mecánico , Articulaciones Tarsianas/fisiopatología , Articulaciones Tarsianas/cirugía , Tendones/fisiopatología , Tendones/cirugía
17.
Front Immunol ; 11: 586251, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33193411

RESUMEN

Allogeneic hematopoietic stem cell transplants can lead to dramatic reductions in human immunodeficiency virus (HIV) reservoirs. This effect is partially mediated by donor T cells recognizing lymphocyte-expressed minor histocompatibility antigens (mHAgs). The potential to mark malignant and latently infected cells for destruction makes mHAgs attractive targets for cellular immunotherapies. However, testing such HIV reservoir reduction strategies will likely require preclinical studies in non-human primates (NHPs). In this study, we used a combination of alloimmunization, whole exome sequencing, and bioinformatics to identify an mHAg in Mauritian cynomolgus macaques (MCMs). We mapped the minimal optimal epitope to a 10-mer peptide (SW10) in apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3C (APOBEC3C) and determined the major histocompatibility complex class I restriction element as Mafa-A1∗063, which is expressed in almost 90% of MCMs. APOBEC3C SW10-specific CD8+ T cells recognized immortalized B cells but not fibroblasts from an mHAg-positive MCM. These results provide a framework for identifying mHAgs in a non-transplant setting and suggest that APOBEC3C SW10 could be used as a model antigen to test mHAg-targeted therapies in NHPs.


Asunto(s)
Citidina Desaminasa/inmunología , Macaca fascicularis/inmunología , Antígenos de Histocompatibilidad Menor/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Modelos Animales de Enfermedad , Epítopos de Linfocito T/inmunología
18.
PLoS One ; 14(12): e0224694, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31830044

RESUMEN

BACKGROUND: Excessive hindfoot pronation, talotarsal joint (TTJ) instability, has been attributed to an increase in medial knee compartment pathology. Advocacy for hindfoot realignment has been the subject of research. An internal solution for TTJ instability, extra-osseous talotarsal stabilization (EOTTS), exists but its effect on knee forces is unknown. This is the first study to measure the in vivo forces acting within the medial knee compartment before and after EOTTS. We hypothesized that following EOTTS there should be a reduction of force acting on the medial knee compartment. METHODS: 10 fresh frozen cadaver lower extremities exhibiting clinical and radiographic evidence of TTJ instability were evaluated. The proximal femur segment was mounted to a mechanical testing unit. Pressure sensors were placed within the medial knee compartment. A force of 1000 newtons was then applied, and the femur was internally rotated 10 degrees. Measurements were recorded before and after the insertion of a type II EOTTS stent. RESULTS: Pre-EOTTS resulted in an average of 842 ± 247N acting within the medial knee joint compartment. These forces then decreased to an average of 565 ± 260N (<0.05) following EOTTS, representing an average reduction of force by 32.8%. CONCLUSION: EOTTS has been shown to decrease the in vivo forces action within the medial knee compartment. This helps to further illustrate the importance of realigning and stabilizing the hindfoot for the prevention and treatment of chronic knee pain.


Asunto(s)
Inestabilidad de la Articulación/prevención & control , Articulación de la Rodilla/cirugía , Rango del Movimiento Articular , Estrés Mecánico , Articulaciones Tarsianas/cirugía , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Cadáver , Humanos , Articulación de la Rodilla/fisiopatología , Persona de Mediana Edad , Articulaciones Tarsianas/fisiopatología
20.
Nat Commun ; 8(1): 169, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28765581

RESUMEN

Zika virus is present in urine, saliva, tears, and breast milk, but the transmission risk associated with these body fluids is currently unknown. Here we evaluate the risk of Zika virus transmission through mucosal contact in rhesus macaques. Application of high-dose Zika virus directly to the tonsils of three rhesus macaques results in detectable plasma viremia in all animals by 2 days post-exposure; virus replication kinetics are similar to those observed in animals infected subcutaneously. Three additional macaques inoculated subcutaneously with Zika virus served as saliva donors to assess the transmission risk from contact with oral secretions from an infected individual. Seven naive animals repeatedly exposed to donor saliva via the conjunctivae, tonsils, or nostrils did not become infected. Our results suggest that there is a risk of Zika virus transmission via the mucosal route, but that the risk posed by oral secretions from individuals with a typical course of Zika virus infection is low.Zika virus (ZIKV) is present in body fluids, including saliva, but transmission risk through mucosal contact is not well known. Here, the authors show that oropharyngeal mucosal infection of macaques with a high ZIKV dose results in viremia, but that transmission risk from saliva of infected animals is low.


Asunto(s)
Membrana Mucosa/virología , Orofaringe/virología , Saliva/virología , Viremia/transmisión , Infección por el Virus Zika/transmisión , Virus Zika , Animales , Macaca mulatta , Replicación Viral
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