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1.
Am J Physiol Cell Physiol ; 326(1): C40-C49, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37955120

RESUMEN

The blood-brain barrier is composed of microvascular endothelial cells, immune cells, and astrocytes that work in concert with the coagulation cascade to control inflammation and immune cell infiltration into the central nervous system. Endothelial cell dysfunction leading to increased permeability and compromised barrier function are hallmarks of neuroinflammatory and autoimmune disorders, including multiple sclerosis (MS). Therapeutic strategies that improve or protect endothelial barrier function may be beneficial in the treatment or prevention of neuroinflammatory diseases. We therefore tested the hypothesis that biasing thrombin toward anticoagulant and cytoprotective activities would provide equivalent or even additive benefit compared with standard-of-care therapeutic strategies, including corticosteroids. In a mouse model of relapsing-remitting MS, treatment with the thrombin mutant, E-WE thrombin, an engineered thrombin mutant with cytoprotective activities that is biased toward anticoagulant and cytoprotective activity, reduced neuroinflammation and extracellular fibrin formation in SJL mice inoculated with proteolipid protein (PLP) peptide. When administered at the onset of detectable disease, E-WE thrombin significantly improved the disease severity of the initial attack as well as the relapse and delayed the onset of relapse to a similar extent as observed with methylprednisolone. Both methylprednisolone and E-WE thrombin reduced demyelination and immune cell recruitment. These results provide rationale for considering engineered forms of thrombin biased toward anticoagulant and cytoprotective activity as a therapeutic strategy and perhaps an effective alternative to high-dose methylprednisolone for the management of acute relapsing MS attacks.NEW & NOTEWORTHY There are limited treatment options for mitigating acute relapsing attacks for patients with multiple sclerosis. We tested the hypothesis that harnessing the cytoprotective activity of the blood coagulation enzyme, thrombin, would provide benefit and protection against relapsing disease in a mouse model of MS. Our results provide rationale for considering engineered forms of thrombin biased toward cytoprotective activity as a therapeutic strategy and perhaps an alternative to steroids for the management of relapsing MS attacks.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Trombina , Animales , Humanos , Ratones , Anticoagulantes , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Metilprednisolona , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Gravedad del Paciente , Recurrencia , Trombina/uso terapéutico
2.
Metab Brain Dis ; 36(3): 407-420, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33411219

RESUMEN

The coagulation cascade and immune system are intricately linked, highly regulated and respond cooperatively in response to injury and infection. Increasingly, evidence of hyper-coagulation has been associated with autoimmune disorders, including multiple sclerosis (MS). The pathophysiology of MS includes immune cell activation and recruitment to the central nervous system (CNS) where they degrade myelin sheaths, leaving neuronal axons exposed to damaging inflammatory mediators. Breakdown of the blood-brain barrier (BBB) facilitates the entry of peripheral immune cells. Evidence of thrombin activity has been identified within the CNS of MS patients and studies using animal models of experimental autoimmune encephalomyelitis (EAE), suggest increased thrombin generation and activity may play a role in the pathogenesis of MS as well as inhibit remyelination processes. Thrombin is a serine protease capable of cleaving multiple substrates, including protease activated receptors (PARs), fibrinogen, and protein C. Cleavage of all three of these substrates represent pathways through which thrombin activity may exert immuno-regulatory effects and regulate permeability of the BBB during MS and EAE. In this review, we summarize evidence that thrombin activity directly, through PARs, and indirectly, through fibrin formation and activation of protein C influences neuro-immune responses associated with MS and EAE pathology.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Esclerosis Múltiple/metabolismo , Trombina/metabolismo , Animales , Sistema Nervioso Central/metabolismo , Humanos
3.
Glia ; 68(2): 263-279, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31490574

RESUMEN

Myelination delay and remyelination failure following insults to the central nervous system (CNS) impede axonal conduction and lead to motor, sensory and cognitive impairments. Both myelination and remyelination are often inhibited or delayed due to the failure of oligodendrocyte progenitor cells (OPCs) to mature into myelinating oligodendrocytes (OLs). Digestion products of the glycosaminoglycan hyaluronan (HA) have been implicated in blocking OPC maturation, but how these digestion products are generated is unclear. We tested the possibility that hyaluronidase activity is directly linked to the inhibition of OPC maturation by developing a novel modified flavonoid that functions as a hyaluronidase inhibitor. This compound, called S3, blocks some but not all hyaluronidases and only inhibits matrix metalloproteinase activity at high concentrations. We find that S3 reverses HA-mediated inhibition of OPC maturation in vitro, an effect that can be overcome by excess recombinant hyaluronidase. Furthermore, we find that hyaluronidase inhibition by S3 accelerates OPC maturation in an in vitro model of perinatal white matter injury. Finally, blocking hyaluronidase activity with S3 promotes functional remyelination in mice with lysolecithin-induced demyelinating corpus callosum lesions. All together, these findings support the notion that hyaluronidase activity originating from OPCs in CNS lesions is sufficient to prevent OPC maturation, which delays myelination or blocks remyelination. These data also indicate that modified flavonoids can act as selective inhibitors of hyaluronidase activity and can promote OPC maturation, making them excellent candidates to accelerate myelination or promote remyelination following perinatal and adult CNS insults.


Asunto(s)
Enfermedades Desmielinizantes/patología , Células Precursoras de Oligodendrocitos/citología , Oligodendroglía/metabolismo , Remielinización/fisiología , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Vaina de Mielina/metabolismo , Neurogénesis/fisiología , Células Madre/metabolismo
4.
J Hand Surg Am ; 44(3): 245.e1-245.e5, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30853063

RESUMEN

PURPOSE: The goal of this study was to quantify the variation in daily volume that is expected in the normal hand. Our hypothesis is that hand swelling occurs overnight. METHODS: Hand volume measurements of 36 healthy volunteers with no hand pathology were taken daily at 8 am, 2 pm, and 8 pm over a 3-day period. Participants were blinded to the objective of the study. Statistical analysis was performed to determine if any of the time points or patient demographics were associated with an increased change in hand volume. RESULTS: Thirty-six healthy volunteers with mean age of 40.9 years and mean body mass index of 24.2 kg/m2 were enrolled. Twenty-one volunteers were men and 15 were women. Three of the volunteers were left-handed. The key finding from this study was that the change in hand volume overnight (8 pm-8 am) is significantly different than the change in hand volume from 8 am to 2 pm and from 2 pm to 8 pm. Although there was a significant reduction in hand volume from 8 am to 2 pm, the further reduction in hand volume from 2 pm to 8 pm was not significant after correcting for the number of post hoc comparisons. In addition, demographic variables such as age, body mass index, and sex did not influence changes in hand volume. CONCLUSIONS: Physiological hand swelling occurs overnight in individuals without active or prior hand pathology. Hand volume then decreases over the course of the day in these same individuals. CLINICAL RELEVANCE: By investigating the changes in hand volume that occur overnight and throughout the day, we gain a better understanding of the temporal relationship between hand swelling and symptoms of chronic hand disease.


Asunto(s)
Ritmo Circadiano/fisiología , Edema/fisiopatología , Mano/fisiología , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Estudios Prospectivos
5.
Artículo en Inglés | MEDLINE | ID: mdl-29229636

RESUMEN

Topical antibiotics, such as mupirocin and fusidic acid, are commonly used in the prevention and treatment of skin infections, particularly those caused by staphylococci. However, the widespread use of these agents is associated with increased resistance to these agents, potentially limiting their efficacy. Of particular concern is the observation that resistance to topical antibiotics is often associated with multidrug resistance, suggesting that topical antibiotics may play a role in the emergence of multidrug-resistant (MDR) strains. New Zealand (NZ) has some of the highest globally recorded rates of topical antibiotic usage and resistance. Using a combination of Pacific Biosciences single-molecule real-time (SMRT) whole-genome sequencing, Illumina short-read sequencing, and Bayesian phylogenomic modeling on 118 new multilocus sequence type 1 (ST1) community Staphylococcus aureus isolates from New Zealand and 61 publically available international ST1 genome sequences, we demonstrate a strong correlation between the clinical introduction of topical antibiotics and the emergence of MDR ST1 S. aureus We also provide in vitro experimental evidence showing that exposure to topical antibiotics can lead to the rapid selection of MDR S. aureus isolates carrying plasmids that confer resistance to multiple unrelated antibiotics, from within a mixed population of competitor strains. These findings have important implications regarding the impact of the indiscriminate use of topical antibiotics.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Administración Tópica , Teorema de Bayes , Farmacorresistencia Bacteriana Múltiple/genética , Ácido Fusídico/farmacología , Genoma Bacteriano/efectos de los fármacos , Genoma Bacteriano/genética , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Mupirocina/farmacología , Nueva Zelanda , Infecciones Cutáneas Estafilocócicas/tratamiento farmacológico , Infecciones Cutáneas Estafilocócicas/microbiología , Staphylococcus aureus/genética
6.
N Engl J Med ; 369(16): 1502-11, 2013 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-24088041

RESUMEN

BACKGROUND: Whole-exome sequencing is a diagnostic approach for the identification of molecular defects in patients with suspected genetic disorders. METHODS: We developed technical, bioinformatic, interpretive, and validation pipelines for whole-exome sequencing in a certified clinical laboratory to identify sequence variants underlying disease phenotypes in patients. RESULTS: We present data on the first 250 probands for whom referring physicians ordered whole-exome sequencing. Patients presented with a range of phenotypes suggesting potential genetic causes. Approximately 80% were children with neurologic phenotypes. Insurance coverage was similar to that for established genetic tests. We identified 86 mutated alleles that were highly likely to be causative in 62 of the 250 patients, achieving a 25% molecular diagnostic rate (95% confidence interval, 20 to 31). Among the 62 patients, 33 had autosomal dominant disease, 16 had autosomal recessive disease, and 9 had X-linked disease. A total of 4 probands received two nonoverlapping molecular diagnoses, which potentially challenged the clinical diagnosis that had been made on the basis of history and physical examination. A total of 83% of the autosomal dominant mutant alleles and 40% of the X-linked mutant alleles occurred de novo. Recurrent clinical phenotypes occurred in patients with mutations that were highly likely to be causative in the same genes and in different genes responsible for genetically heterogeneous disorders. CONCLUSIONS: Whole-exome sequencing identified the underlying genetic defect in 25% of consecutive patients referred for evaluation of a possible genetic condition. (Funded by the National Human Genome Research Institute.).


Asunto(s)
Exoma , Enfermedades Genéticas Congénitas/diagnóstico , Pruebas Genéticas/métodos , Análisis de Secuencia de ADN/métodos , Adolescente , Niño , Preescolar , Genes Dominantes , Genes Recesivos , Genes Ligados a X , Enfermedades Genéticas Congénitas/genética , Humanos , Mutación , Fenotipo , Adulto Joven
7.
Dev Biol ; 382(1): 160-71, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23872330

RESUMEN

Actin dynamics are necessary at multiple steps in the formation of multinucleated muscle cells. BAR domain proteins can regulate actin dynamics in several cell types, but have been little studied in skeletal muscle. Here, we identify novel functions for the N-BAR domain protein, Bridging integrator 3 (Bin3), during myogenesis in mice. Bin3 plays an important role in regulating myofiber size in vitro and in vivo. During early myogenesis, Bin3 promotes migration of differentiated muscle cells, where it colocalizes with F-actin in lamellipodia. In addition, Bin3 forms a complex with Rac1 and Cdc42, Rho GTPases involved in actin polymerization, which are known to be essential for myotube formation. Importantly, a Bin3-dependent pathway is a major regulator of Rac1 and Cdc42 activity in differentiated muscle cells. Overall, these data classify N-BAR domain proteins as novel regulators of actin-dependent processes in myogenesis, and further implicate BAR domain proteins in muscle growth and repair.


Asunto(s)
Proteínas de Microfilamentos/química , Proteínas de Microfilamentos/metabolismo , Desarrollo de Músculos , Neuropéptidos/metabolismo , Proteína de Unión al GTP cdc42/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Actinas/metabolismo , Animales , Movimiento Celular , Endocitosis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Microfilamentos/deficiencia , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiología , Estructura Terciaria de Proteína , Seudópodos/metabolismo , Regeneración
8.
Aust Endod J ; 50(2): 276-284, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38288530

RESUMEN

The aim of this study was to assess whether calcium silicate root fillings prevent bacterial penetration and to determine how bacteria penetrate roots. Extracted single-rooted, single-canal human teeth were decoronated, prepared and filled with ProRootMTA or Biodentine (n = 12 each). Positive and negative (n = 2 each) controls were not filled. A two-chamber model was used with Streptococcus gordonii. The lower compartment was evaluated for turbidity over 150 days. Roots were split and examined for bacteria via SEM. The chi-squared test was used for comparisons (α = 0.05). Experimental groups had bacteria in their coronal thirds. Tubules contained bacteria in 90.9% and 91.7% of areas examined in the Biodentine and ProRootMTA groups, respectively, with no significant difference (p = 0.914). Experimental and negative roots had no turbidity with no significant difference between Biodentine and ProRootMTA (p = 1.000). Positive controls had turbidity. Bacteria penetrate roots via dentine tubules of root-filled teeth. Biodentine was comparable to ProRoot MTA.


Asunto(s)
Compuestos de Calcio , Dentina , Materiales de Obturación del Conducto Radicular , Silicatos , Streptococcus gordonii , Compuestos de Calcio/farmacología , Silicatos/farmacología , Humanos , Dentina/microbiología , Dentina/efectos de los fármacos , Materiales de Obturación del Conducto Radicular/farmacología , Streptococcus gordonii/efectos de los fármacos , Streptococcus gordonii/fisiología , Cavidad Pulpar/microbiología , Combinación de Medicamentos , Microscopía Electrónica de Rastreo , Técnicas In Vitro , Óxidos/farmacología , Compuestos de Aluminio/farmacología , Ensayo de Materiales , Nefelometría y Turbidimetría , Preparación del Conducto Radicular/métodos
9.
Bioengineering (Basel) ; 10(11)2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-38002424

RESUMEN

Thrombin is a key enzyme involved in the development and progression of many cardiovascular diseases. Direct thrombin inhibitors (DTIs), with their minimum off-target effects and immediacy of action, have greatly improved the treatment of these diseases. However, the risk of bleeding, pharmacokinetic issues, and thrombotic complications remain major concerns. In an effort to increase the effectiveness of the DTI discovery pipeline, we developed a two-stage machine learning pipeline to identify and rank peptide sequences based on their effective thrombin inhibitory potential. The positive dataset for our model consisted of thrombin inhibitor peptides and their binding affinities (KI) curated from published literature, and the negative dataset consisted of peptides with no known thrombin inhibitory or related activity. The first stage of the model identified thrombin inhibitory sequences with Matthew's Correlation Coefficient (MCC) of 83.6%. The second stage of the model, which covers an eight-order of magnitude range in KI values, predicted the binding affinity of new sequences with a log room mean square error (RMSE) of 1.114. These models also revealed physicochemical and structural characteristics that are hidden but unique to thrombin inhibitor peptides. Using the model, we classified more than 10 million peptides from diverse sources and identified unique short peptide sequences (<15 aa) of interest, based on their predicted KI. Based on the binding energies of the interaction of the peptide with thrombin, we identified a promising set of putative DTI candidates. The prediction pipeline is available on a web server.

10.
Res Sq ; 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37131631

RESUMEN

Objective: Relapses in patients with relapsing-remitting multiple sclerosis (RRMS) are typically treated with high-dose corticosteroids including methylprednisolone. However, high-dose corticosteroids are associated with significant adverse effects, can increase the risk for other morbidities, and often do not impact disease course. Multiple mechanisms are proposed to contribute to acute relapses in RRMS patients, including neuroinflammation, fibrin formation and compromised blood vessel barrier function. The protein C activator, E-WE thrombin is a recombinant therapeutic in clinical development for its antithrombotic and cytoprotective properties, including protection of endothelial cell barrier function. In mice, treatment with E-WE thrombin reduced neuroinflammation and extracellular fibrin formation in myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE). We therefore tested the hypothesis that E-WE thrombin could reduce disease severity in a relapsing-remitting model of EAE. Methods: Female SJL mice were inoculated with proteolipid protein (PLP) peptide and treated with E-WE thrombin (25 µg/kg; iv) or vehicle at onset of detectable disease. In other experiments, E-WE thrombin was compared to methylprednisolone (100 mg/kg; iv) or the combination of both. Results: Compared to vehicle, administration of E-WE thrombin significantly improved disease severity of the initial attack and relapse and delayed onset of relapse as effectively as methylprednisolone. Both methylprednisolone and E-WE thrombin reduced demyelination and immune cell recruitment, and the combination of both treatments had an additive effect. Conclusion: The data presented herein demonstrate that E-WE thrombin is protective in mice with relapsing-remitting EAE, a widely used model of MS. Our data indicate that E-WE thrombin is as effective as high-dose methylprednisolone in improving disease score and may exert additional benefit when administered in combination. Taken together, these data suggest that E-WE thrombin may be an effective alternative to high-dose methylprednisolone for managing acute MS attacks.

11.
Digit Health ; 9: 20552076231180727, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37325078

RESUMEN

Introduction: The unmet need for remote monitoring of visual function with home-based, patient-centric technologies became increasingly palpable during the COVID-19 pandemic. Many patients with chronic eye conditions lack access to office-based examinations. Here, we evaluate the efficacy of the Accustat® test, a virtual application for measuring near visual acuity on any portable electronic device via telehealth. Materials and methods: Thirty-three adult subjects from the telehealth remote monitoring service of a retina practice performed the Accustat® acuity testing at home. All patients underwent in-office general eye examination with additional fundoscopic examination and optical coherence tomography retina imaging. Best corrected visual acuity assessment using a Snellen chart was compared with remote visual acuity assessment with the Accustat® test. Visual acuity was analyzed and compared between the best-corrected near visual acuity potential achieved on the Accustat® and in-office distance best-corrected Snellen visual acuity. Results: The mean logarithm of the minimum angle of resolution (logMAR) visual acuities of all eyes tested using the Accustat test was 0.19 ± 024 and for the office Snellen test 0.21 ± 0.21. A linear regression model with 95% confidence intervals reveals that there is a strong linear relationship between Accustat logMAR and office Snellen logMAR. Bland-Altman analysis demonstrated 95.2% significant agreement between Accustat and Office Snellen's best corrected visual acuity. Intraclass correlation coefficient (ICC = 0.94) demonstrated a strong positive correlation between at home versus office visual acuity. Conclusion: There was a high correlation between the visual acuity measured with the Accustat near vision digital self-test and the office Snellen acuity test, suggesting the potential utility of scalable remote monitoring of central retinal function via telehealth.

12.
BMC Genomics ; 13 Suppl 6: S19, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23134663

RESUMEN

BACKGROUND: Until recently, sequencing has primarily been carried out in large genome centers which have invested heavily in developing the computational infrastructure that enables genomic sequence analysis. The recent advancements in next generation sequencing (NGS) have led to a wide dissemination of sequencing technologies and data, to highly diverse research groups. It is expected that clinical sequencing will become part of diagnostic routines shortly. However, limited accessibility to computational infrastructure and high quality bioinformatic tools, and the demand for personnel skilled in data analysis and interpretation remains a serious bottleneck. To this end, the cloud computing and Software-as-a-Service (SaaS) technologies can help address these issues. RESULTS: We successfully enabled the Atlas2 Cloud pipeline for personal genome analysis on two different cloud service platforms: a community cloud via the Genboree Workbench, and a commercial cloud via the Amazon Web Services using Software-as-a-Service model. We report a case study of personal genome analysis using our Atlas2 Genboree pipeline. We also outline a detailed cost structure for running Atlas2 Amazon on whole exome capture data, providing cost projections in terms of storage, compute and I/O when running Atlas2 Amazon on a large data set. CONCLUSIONS: We find that providing a web interface and an optimized pipeline clearly facilitates usage of cloud computing for personal genome analysis, but for it to be routinely used for large scale projects there needs to be a paradigm shift in the way we develop tools, in standard operating procedures, and in funding mechanisms.


Asunto(s)
Genoma Humano , Programas Informáticos , Bases de Datos Genéticas , Humanos , Internet , Interfaz Usuario-Computador
13.
Semin Musculoskelet Radiol ; 16(4): 331-7, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23047280

RESUMEN

Ulnar-sided wrist pain is one of the most common symptoms in athletes of baseball, racket sports, golf, and wrestling where there is frequent use of the hands as well as in soccer and running, where hand use is minimal. Compared with all wrist injuries, ulnar-sided wrist injury is a relatively serious condition for athletes because it plays an important role in performing a strong grip and in the rotation of the forearm. Ulnar-sided wrist pain in athletes can be related to acute trauma or chronic overuse. Acute trauma can lead to bone fractures and sprains/tears of ligaments. Repetitive mechanical stresses to tendons, ligaments, and the joint structures can lead to tendinitis or osteoarthrosis. Diagnosis of the ulnar-sided wrist pain is challenging both for hand surgeons and radiologists because of the small and complex anatomy. In the present article, we discuss mechanisms of wrist injury, sports-specific ulnar-sided wrist injuries, and the differential diagnosis of ulnar-sided wrist pain.


Asunto(s)
Artralgia/etiología , Traumatismos en Atletas/diagnóstico , Traumatismos de la Muñeca/diagnóstico , Trastornos de Traumas Acumulados/diagnóstico , Diagnóstico Diferencial , Traumatismos de los Dedos/diagnóstico , Fracturas Óseas/diagnóstico , Humanos , Radiografía , Tendinopatía/diagnóstico , Traumatismos de los Tendones/diagnóstico , Fibrocartílago Triangular/anatomía & histología , Fibrocartílago Triangular/diagnóstico por imagen , Fibrocartílago Triangular/lesiones , Cúbito
14.
J Orthop ; 16(3): 206-210, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30906124

RESUMEN

PURPOSE: Myxoid liposarcoma has a propensity to metastasize to bone. MRI is the preferred modality for detecting bone disease. We evaluated multiple MRI sequences to determine an optimal screening method. METHODS: Whole body MRI was performed on all patients. The number and locations of metastases found by imaging and round cell component of the sites sampled were evaluated. RESULTS: We found a total of 68 osseous lesions. Whole body MRI utilizing STIR only sequences decreased imaging time by 83.6% and demonstrated the lesions the best. CONCLUSIONS: STIR sequences can be exclusively used during staging and screening of myxoid liposarcoma.

16.
Cells ; 8(4)2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-31010245

RESUMEN

Reduced risk of HIV-1 infection correlated with antibody responses to the envelope variable 1 and 2 regions in the RV144 vaccine trial. To understand the relationship between antibody responses, V2 sequence, and structure, plasma samples (n = 16) from an early acute HIV-1 infection cohort from Thailand infected with CRF01_AE strain were analyzed for binding to V2 peptides by surface plasmon resonance. Five participants with a range of V2 binding responses at week 24 post-infection were further analyzed against a set of four overlapping V2 peptides that were designed based on envelope single-genome amplification. Antibody responses that were relatively consistent over the four segments of the V2 region or a focused response to the C-strand (residues 165-186) of the V2 region were observed. Viral escape in the V2 region resulted in significantly reduced antibody binding. Structural modeling indicated that the C-strand and the sites of viral variation were highly accessible in the open conformation of the HIV-1 Env trimer. V2 residues, 165-186 are preferentially targeted during acute infection. Residues 169-184 were also preferentially targeted by the protective immune response in the RV144 trial, thus emphasizing the importance of these residues for vaccine design.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Vacunas contra el SIDA/administración & dosificación , Secuencia de Aminoácidos/genética , Anticuerpos Neutralizantes/sangre , Estudios de Cohortes , Proteína gp120 de Envoltorio del VIH/genética , Proteína gp120 de Envoltorio del VIH/ultraestructura , Seropositividad para VIH , Humanos , Inmunidad Humoral
17.
Artículo en Inglés | MEDLINE | ID: mdl-29668298

RESUMEN

BACKGROUND: There are over ten classification systems currently used in the staging of hallux rigidus. This results in confusion and inconsistency with radiographic interpretation and treatment. The reliability of hallux rigidus classification systems has not yet been tested. The purpose of this study was to evaluate intra- and interobserver reliability using three commonly used classifications for hallux rigidus. METHODS: Twenty-one plain radiograph sets were presented to ten ACFAS board-certified foot and ankle surgeons. Each physician classified each radiograph based on clinical experience and knowledge according to the Regnauld, Roukis, and Hattrup and Johnson classification systems. The two-way mixed single-measure consistency intraclass correlation was used to calculate intra- and interrater reliability. RESULTS: The intrarater reliability of individual sets for the Roukis and Hattrup and Johnson classification systems was "fair to good" (Roukis, 0.62±0.19; Hattrup and Johnson, 0.62±0.28), whereas the intrarater reliability of individual sets for the Regnauld system bordered between "fair to good" and "poor" (0.43±0.24). The interrater reliability of the mean classification was "excellent" for all three classification systems. Conclusions Reliable and reproducible classification systems are essential for treatment and prognostic implications in hallux rigidus. In our study, Roukis classification system had the best intrarater reliability. Although there are various classification systems for hallux rigidus, our results indicate that all three of these classification systems show reliability and reproducibility.

18.
PLoS One ; 12(7): e0182376, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28759645

RESUMEN

OBJECTIVE: Recent surveillance data suggests the United States (U.S.) Army HIV epidemic is concentrated among men who have sex with men. To identify potential targets for HIV prevention strategies, the relationship between demographic and clinical factors and membership within transmission clusters based on baseline pol sequences of HIV-infected Soldiers from 2001 through 2012 were analyzed. METHODS: We conducted a retrospective analysis of baseline partial pol sequences, demographic and clinical characteristics available for all Soldiers in active service and newly-diagnosed with HIV-1 infection from January 1, 2001 through December 31, 2012. HIV-1 subtype designations and transmission clusters were identified from phylogenetic analysis of sequences. Univariate and multivariate logistic regression models were used to evaluate and adjust for the association between characteristics and cluster membership. RESULTS: Among 518 of 995 HIV-infected Soldiers with available partial pol sequences, 29% were members of a transmission cluster. Assignment to a southern U.S. region at diagnosis and year of diagnosis were independently associated with cluster membership after adjustment for other significant characteristics (p<0.10) of age, race, year of diagnosis, region of duty assignment, sexually transmitted infections, last negative HIV test, antiretroviral therapy, and transmitted drug resistance. Subtyping of the pol fragment indicated HIV-1 subtype B infection predominated (94%) among HIV-infected Soldiers. CONCLUSION: These findings identify areas to explore as HIV prevention targets in the U.S. Army. An increased frequency of current force testing may be justified, especially among Soldiers assigned to duty in installations with high local HIV prevalence such as southern U.S. states.


Asunto(s)
Infecciones por VIH/epidemiología , Personal Militar/estadística & datos numéricos , Adolescente , Adulto , Femenino , Infecciones por VIH/transmisión , Humanos , Masculino , Persona de Mediana Edad , Estados Unidos
19.
Invest Radiol ; 41(9): 674-80, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16896302

RESUMEN

OBJECTIVES: We examined the relationship between computed tomography (CT)-quantified calcium and histopathologic atherosclerotic plaque morphology and rupture. MATERIALS AND METHODS: Seven aortae were harvested from autopsy cases. All were scanned, ex vivo, on a 16-slice CT scanner and CT calcium scores (CTCS) were calculated using a Siemens Calcium Scoring package. The aorta segments were physically cross sectioned at 3-mm intervals corresponding to CT reconstructions. Two pathologists evaluated the cross sections for histology calcium score (HCS), plaque fibrous cap disruption, overlying thrombus, internal hemorrhage, size, lipid content, and inflammation. CT and histology data were subsequently paired using predetermined quadrant and slice conventions. RESULTS: Three hundred forty-nine aorta cross sections yielded 41 atherosclerotic plaques. Eleven plaques demonstrated plaque disruption and thrombosis and all contained calcium. CTCS was not significantly different between atherosclerotic plaques with and without evidence of disruption/thrombosis (F[1,30] = 1.525, P = 0.227). CT was 100% sensitive for nodular calcification, but only 56% (5 of 9 plaques) sensitive for non-nodular calcification. There was no significant relationship between CTCS and intraplaque hemorrhage, lipid content, inflammation, and plaque size (P = 0.179, P = 0.230, P = 0.314, and P = 0.054). There was significant correlation between CTCS and HCS (Pearson coefficient = 0.535; P < 0.01). CONCLUSIONS: Calcium quantity does not appear to predict plaque morphology or likelihood of rupture. CT has lower sensitivity for non-nodular compared with nodular calcification.


Asunto(s)
Calcinosis/diagnóstico por imagen , Calcio/análisis , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/patología , Tomografía Computarizada por Rayos X , Calcinosis/patología , Enfermedad de la Arteria Coronaria/patología , Humanos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
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