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1.
Curr Psychiatry Rep ; 24(9): 375-386, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35895282

RESUMEN

PURPOSE OF REVIEW: Telehealth-delivered medication-assisted treatment for opioid use disorder (tele-MOUD) has received increased attention, with the intersection of the opioid epidemic and COVID-19 pandemic, but research on recent developments is scattered. We critically review recent literature on tele-MOUD and synthesize studies reporting primary data under four themes: clinical effectiveness, non-clinical effectiveness, perceptions, and regulatory considerations. RECENT FINDINGS: Despite increasing publications, most failed to include long-term comprehensive assessments. Findings indicate favorable outcomes such as improvements in retention and abstinence rates, positive experiences, and improved feasibility with the relaxation of regulatory measures. With increased adoption, clinician and patient perceptions appeared largely positive. Negative findings, albeit minor, were primarily associated with workflow adaptation difficulties and limited access of underserved populations to technology and internet connection. Additional financial, logistical, outreach, and training support for clinicians, patients, and support staff is recommended, in addition to permanent evidence-based regulatory reforms, to scale and optimize tele-MOUD services. Comprehensive recommendations to overcome limitations are expanded therein.


Asunto(s)
COVID-19 , Trastornos Relacionados con Opioides , Telemedicina , Analgésicos Opioides/uso terapéutico , Humanos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Pandemias
2.
PLoS Comput Biol ; 16(5): e1007890, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32453720

RESUMEN

The biconcave disk shape of the mammalian red blood cell (RBC) is unique to the RBC and is vital for its circulatory function. Due to the absence of a transcellular cytoskeleton, RBC shape is determined by the membrane skeleton, a network of actin filaments cross-linked by spectrin and attached to membrane proteins. While the physical properties of a uniformly distributed actin network interacting with the lipid bilayer membrane have been assumed to control RBC shape, recent experiments reveal that RBC biconcave shape also depends on the contractile activity of nonmuscle myosin IIA (NMIIA) motor proteins. Here, we use the classical Helfrich-Canham model for the RBC membrane to test the role of heterogeneous force distributions along the membrane and mimic the contractile activity of sparsely distributed NMIIA filaments. By incorporating this additional contribution to the Helfrich-Canham energy, we find that the RBC biconcave shape depends on the ratio of forces per unit volume in the dimple and rim regions of the RBC. Experimental measurements of NMIIA densities at the dimple and rim validate our prediction that (a) membrane forces must be non-uniform along the RBC membrane and (b) the force density must be larger in the dimple than the rim to produce the observed membrane curvatures. Furthermore, we predict that RBC membrane tension and the orientation of the applied forces play important roles in regulating this force-shape landscape. Our findings of heterogeneous force distributions on the plasma membrane for RBC shape maintenance may also have implications for shape maintenance in different cell types.


Asunto(s)
Deformación Eritrocítica , Membrana Eritrocítica/fisiología , Eritrocitos/citología , Miosinas/química , Citoesqueleto de Actina/química , Reactivos de Enlaces Cruzados/química , Glicoforinas/química , Humanos , Membrana Dobles de Lípidos/química , Proteínas de la Membrana/química , Microscopía Fluorescente , Cadenas Pesadas de Miosina/química , Faloidina/química , Rodaminas/química , Estrés Mecánico
3.
Proc Natl Acad Sci U S A ; 115(19): E4377-E4385, 2018 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-29610350

RESUMEN

The biconcave disk shape and deformability of mammalian RBCs rely on the membrane skeleton, a viscoelastic network of short, membrane-associated actin filaments (F-actin) cross-linked by long, flexible spectrin tetramers. Nonmuscle myosin II (NMII) motors exert force on diverse F-actin networks to control cell shapes, but a function for NMII contractility in the 2D spectrin-F-actin network of RBCs has not been tested. Here, we show that RBCs contain membrane skeleton-associated NMIIA puncta, identified as bipolar filaments by superresolution fluorescence microscopy. MgATP disrupts NMIIA association with the membrane skeleton, consistent with NMIIA motor domains binding to membrane skeleton F-actin and contributing to membrane mechanical properties. In addition, the phosphorylation of the RBC NMIIA heavy and light chains in vivo indicates active regulation of NMIIA motor activity and filament assembly, while reduced heavy chain phosphorylation of membrane skeleton-associated NMIIA indicates assembly of stable filaments at the membrane. Treatment of RBCs with blebbistatin, an inhibitor of NMII motor activity, decreases the number of NMIIA filaments associated with the membrane and enhances local, nanoscale membrane oscillations, suggesting decreased membrane tension. Blebbistatin-treated RBCs also exhibit elongated shapes, loss of membrane curvature, and enhanced deformability, indicating a role for NMIIA contractility in promoting membrane stiffness and maintaining RBC biconcave disk cell shape. As structures similar to the RBC membrane skeleton exist in many metazoan cell types, these data demonstrate a general function for NMII in controlling specialized membrane morphology and mechanical properties through contractile interactions with short F-actin in spectrin-F-actin networks.


Asunto(s)
Actinas/metabolismo , Forma de la Célula/fisiología , Membrana Eritrocítica/metabolismo , Miosina Tipo IIA no Muscular/metabolismo , Adenosina Trifosfato/metabolismo , Forma de la Célula/efectos de los fármacos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Humanos
4.
J Immunol ; 200(2): 788-799, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29246954

RESUMEN

Ligation of Dectin-1 by fungal glucans elicits a Th17 response that is necessary for clearing many fungal pathogens. Laminarin is a (1→3, 1→6)-ß-glucan that is widely reported to be a Dectin-1 antagonist, however, there are reports that laminarin is also a Dectin-1 agonist. To address this controversy, we assessed the physical properties, structure, purity, Dectin-1 binding, and biological activity of five different laminarin preparations from three different commercial sources. The proton nuclear magnetic resonance analysis indicated that all of the preparations contained laminarin although their molecular mass varied considerably (4400-34,400 Da). Two of the laminarins contained substantial quantities of very low m.w. compounds, some of which were not laminarin. These low m.w. moieties could be significantly reduced by extensive dialysis. All of the laminarin preparations were bound by recombinant human Dectin-1 and mouse Dectin-1, but the affinity varied considerably, and binding affinity did not correlate with Dectin-1 agonism, antagonism, or potency. In both human and mouse cells, two laminarins were Dectin-1 antagonists and two were Dectin-1 agonists. The remaining laminarin was a Dectin-1 antagonist, but when the low m.w. moieties were removed, it became an agonist. We were able to identify a laminarin that is a Dectin-1 agonist and a laminarin that is Dectin-1 antagonist, both of which are relatively pure preparations. These laminarins may be useful in elucidating the structure and activity relationships of glucan/Dectin-1 interactions. Our data demonstrate that laminarin can be either a Dectin-1 antagonist or agonist, depending on the physicochemical properties, purity, and structure of the laminarin preparation employed.


Asunto(s)
Productos Biológicos/farmacología , Glucanos/farmacología , Factores Inmunológicos/farmacología , Inmunomodulación/efectos de los fármacos , Animales , Productos Biológicos/química , Línea Celular , Citocinas/metabolismo , Técnicas de Silenciamiento del Gen , Glucanos/química , Humanos , Factores Inmunológicos/química , Lectinas Tipo C/química , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Leucocitos Mononucleares , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Polímeros/química , Polímeros/farmacología , Unión Proteica , Espectroscopía de Protones por Resonancia Magnética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
5.
Am J Hematol ; 94(6): 667-677, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30916803

RESUMEN

MYH9-related disease (MYH9-RD) is a rare, autosomal dominant disorder caused by mutations in MYH9, the gene encoding the actin-activated motor protein non-muscle myosin IIA (NMIIA). MYH9-RD patients suffer from bleeding syndromes, progressive kidney disease, deafness, and/or cataracts, but the impact of MYH9 mutations on other NMIIA-expressing tissues remains unknown. In human red blood cells (RBCs), NMIIA assembles into bipolar filaments and binds to actin filaments (F-actin) in the spectrin-F-actin membrane skeleton to control RBC biconcave disk shape and deformability. Here, we tested the effects of MYH9 mutations in different NMIIA domains (motor, coiled-coil rod, or non-helical tail) on RBC NMIIA function. We found that MYH9-RD does not cause clinically significant anemia and that patient RBCs have normal osmotic deformability as well as normal membrane skeleton composition and micron-scale distribution. However, analysis of complete blood count data and peripheral blood smears revealed reduced hemoglobin content and elongated shapes, respectively, of MYH9-RD RBCs. Patients with mutations in the NMIIA motor domain had the highest numbers of elongated RBCs. Patients with mutations in the motor domain also had elevated association of NMIIA with F-actin at the RBC membrane. Our findings support a central role for motor domain activity in NMIIA regulation of RBC shape and define a new sub-clinical phenotype of MYH9-RD.


Asunto(s)
Actinas , Membrana Eritrocítica , Eritrocitos Anormales , Pérdida Auditiva Sensorineural , Mutación , Cadenas Pesadas de Miosina , Trombocitopenia/congénito , Actinas/genética , Actinas/metabolismo , Membrana Eritrocítica/genética , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/patología , Eritrocitos Anormales/metabolismo , Eritrocitos Anormales/patología , Femenino , Pérdida Auditiva Sensorineural/genética , Pérdida Auditiva Sensorineural/metabolismo , Pérdida Auditiva Sensorineural/patología , Humanos , Masculino , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Trombocitopenia/genética , Trombocitopenia/metabolismo , Trombocitopenia/patología
6.
Emerg Infect Dis ; 22(6): 973-80, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27192043

RESUMEN

Single-strain outbreaks of Streptococcus pyogenes infections are common and often go undetected. In 2013, two clusters of invasive group A Streptococcus (iGAS) infection were identified in independent but closely located care homes in Oxfordshire, United Kingdom. Investigation included visits to each home, chart review, staff survey, microbiologic sampling, and genome sequencing. S. pyogenes emm type 1.0, the most common circulating type nationally, was identified from all cases yielding GAS isolates. A tailored whole-genome reference population comprising epidemiologically relevant contemporaneous isolates and published isolates was assembled. Data were analyzed independently using whole-genome multilocus sequencing and single-nucleotide polymorphism analyses. Six isolates from staff and residents of the homes formed a single cluster that was separated from the reference population by both analytical approaches. No further cases occurred after mass chemoprophylaxis and enhanced infection control. Our findings demonstrate the ability of 2 independent analytical approaches to enable robust conclusions from nonstandardized whole-genome analysis to support public health practice.


Asunto(s)
Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes/genética , Alelos , Biología Computacional/métodos , Farmacorresistencia Bacteriana , Genoma Bacteriano , Genómica/métodos , Instituciones de Salud , Humanos , Filogenia , Polimorfismo de Nucleótido Simple , Infecciones Estreptocócicas/prevención & control , Infecciones Estreptocócicas/transmisión , Streptococcus pyogenes/efectos de los fármacos , Streptococcus pyogenes/patogenicidad , Reino Unido/epidemiología , Virulencia/genética , Secuenciación Completa del Genoma
7.
Hum Resour Health ; 14: 9, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26964743

RESUMEN

BACKGROUND: This paper describes a rapid assessment of Cambodia's current system for regulating its health professions. The assessment forms part of a co-design process to set strategic priorities for strengthening health profession regulation to improve the quality and safety of health services. A health system approach for strengthening health professions' regulation is underway and aims to support the Government of Cambodia's plans for scaling up its health workforce, improving health services' safety and quality, and meeting its Association of South East Asian Nations (ASEAN) obligations to facilitate trade in health care services. METHODS: The assessment used a mixed methods approach including: A desktop review of key laws, plans, reports and other documents relating to the regulation of the health professions in Cambodia (medicine, dentistry, midwifery, nursing and pharmacy); Key informant interviews with stakeholders in Cambodia (The term "stakeholders" refers to government officials, people working on health professional regulation, people working for the various health worker training institutions and health workers at the national and provincial level); Surveys and questionnaires to assess Cambodian stakeholder knowledge of regulation; Self-assessments by members of the five Cambodian regulatory councils regarding key capacities and activities of high-performing regulatory bodies; and A rapid literature review to identify: The key functions of health professional regulation; The key issues affecting the Cambodian health sector (including relevant developments in the wider ASEAN region); and "Smart" health profession regulation practices of possible relevance to Cambodia. RESULTS: We found that the current regulatory system only partially meets Cambodia's needs. A number of key regulatory functions are being performed, but overall, the current system was not designed with Cambodia's specific needs in mind. The existing system is also overly complex, with considerable duplication and overlap between governance and regulatory arrangements for the five regulated professions. CONCLUSIONS: There is considerable scope for reform to the current regulatory system to better align the system to Cambodia's: Current needs and circumstances; Health system strategic priorities; and International obligations. Cambodia is also well placed to base its reformed regulatory system on recent developments of "smart regulatory practices" for health professionals.


Asunto(s)
Atención a la Salud , Gobierno , Empleos en Salud/legislación & jurisprudencia , Personal de Salud/legislación & jurisprudencia , Política de Salud , Servicios de Salud , Calidad de la Atención de Salud , Cambodia , Atención a la Salud/normas , Servicios de Salud/normas , Humanos , Recursos Humanos
9.
Proc Biol Sci ; 281(1788): 20140822, 2014 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-24966315

RESUMEN

In convergent evolution, similar phenotypes evolve repeatedly in independent populations, often reflecting adaptation to similar environments. Understanding whether convergent evolution proceeds via similar or different genetic and developmental mechanisms offers insight towards the repeatability and predictability of evolution. Oceanic populations of threespine stickleback fish, Gasterosteus aculeatus, have repeatedly colonized countless freshwater lakes and streams, where new diets lead to morphological adaptations related to feeding. Here, we show that heritable increases in branchial bone length have convergently evolved in two independently derived freshwater stickleback populations. In both populations, an increased bone growth rate in juveniles underlies the convergent adult phenotype, and one population also has a longer cartilage template. Using F2 crosses from these two freshwater populations, we show that two quantitative trait loci (QTL) control branchial bone length at distinct points in development. In both populations, a QTL on chromosome 21 controls bone length throughout juvenile development, and a QTL on chromosome 4 controls bone length only in adults. In addition to these similar developmental profiles, these QTL show similar chromosomal locations in both populations. Our results suggest that sticklebacks have convergently evolved longer branchial bones using similar genetic and developmental programmes in two independently derived populations.


Asunto(s)
Desarrollo Óseo , Branquias/crecimiento & desarrollo , Fenotipo , Sitios de Carácter Cuantitativo , Smegmamorpha/crecimiento & desarrollo , Smegmamorpha/genética , Adaptación Biológica , Animales , Evolución Biológica , Colombia Británica , Femenino , Agua Dulce , Branquias/anatomía & histología , Branquias/embriología , Masculino , Agua de Mar , Smegmamorpha/anatomía & histología , Smegmamorpha/embriología
10.
Front Immunol ; 14: 1280986, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38022590

RESUMEN

TIGIT is an immune checkpoint receptor expressed on activated and memory T cells, immunosuppressive T regulatory cells, and natural killer (NK) cells. TIGIT has emerged as an attractive target for antitumor therapies, due to its proposed immunosuppressive effects on lymphocyte function and T cell activation. We generated an anti-TIGIT monoclonal antibody (mAb) that binds with high affinity to human, non-human primate, and murine TIGIT and through multiple experimental methodologies demonstrated that checkpoint blockade alone is insufficient for antitumor activity. Generating anti-TIGIT mAbs with various Fc backbones we show that muting the Fc-Fcγ receptor (FcγR) interaction failed to drive antitumor activity, while mAbs with Fc functional backbones demonstrate substantial antitumor activity, mediated through activation of antigen-presenting cells (APCs), T cell priming, and NK-mediated depletion of suppressive Tregs and exhausted T cells. Further, nonfucosylation of the Fc backbone resulted in enhanced immune responses and antitumor activity relative to the intact IgG1 backbone. The improved activity correlated with the biased FcγR interaction profile of the nonfucosylated anti-TIGIT mAb, which supports that FcγRIIIa binding with decreased FcγRIIb binding favorably activates APCs and enhances tumor-specific CD8+ T cell responses. The anti-TIGIT mAbs with intact FcγR interacting backbones also demonstrated synergistic enhancement of other standard antitumor treatments, including anti-PD-1 treatment and a model monomethyl auristatin E antibody-drug conjugate. These findings highlight the importance of the anti-TIGIT mAb's Fc backbone to its antitumor activity and the extent to which this activity can be enhanced through nonfucosylation of the backbone.


Asunto(s)
Neoplasias , Receptores de IgG , Ratones , Animales , Receptores Inmunológicos/metabolismo , Anticuerpos Monoclonales/farmacología , Inmunidad Innata
11.
J Immunother Cancer ; 11(10)2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37793853

RESUMEN

BACKGROUND: SGN-B7H4V is a novel investigational vedotin antibody-drug conjugate (ADC) comprising a B7-H4-directed human monoclonal antibody conjugated to the cytotoxic payload monomethyl auristatin E (MMAE) via a protease-cleavable maleimidocaproyl valine citrulline (mc-vc) linker. This vedotin linker-payload system has been clinically validated in multiple Food and Drug Administration approved agents including brentuximab vedotin, enfortumab vedotin, and tisotumab vedotin. B7-H4 is an immune checkpoint ligand with elevated expression on a variety of solid tumors, including breast, ovarian, and endometrial tumors, and limited normal tissue expression. SGN-B7H4V is designed to induce direct cytotoxicity against target cells by binding to B7-H4 on the surface of target cells and releasing the cytotoxic payload MMAE upon internalization of the B7-H4/ADC complex. METHODS: B7-H4 expression was characterized by immunohistochemistry across multiple solid tumor types. The ability of SGN-B7H4V to kill B7-H4-expressing tumor cells in vitro and in vivo in a variety of xenograft tumor models was also evaluated. Finally, the antitumor activity of SGN-B7H4V as monotherapy and in combination with an anti-programmed cell death-1 (PD-1) agent was evaluated using an immunocompetent murine B7-H4-expressing Renca tumor model. RESULTS: Immunohistochemistry confirmed B7-H4 expression across multiple solid tumors, with the highest prevalence in breast, endometrial, and ovarian tumors. In vitro, SGN-B7H4V killed B7-H4-expressing tumor cells by MMAE-mediated direct cytotoxicity and antibody-mediated effector functions including antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis. In vivo, SGN-B7H4V demonstrated strong antitumor activity in multiple xenograft models of breast and ovarian cancer, including xenograft tumors with heterogeneous B7-H4 expression, consistent with the ability of vedotin ADCs to elicit a bystander effect. In an immunocompetent murine B7-H4-expressing tumor model, SGN-B7H4V drove robust antitumor activity as a monotherapy that was enhanced when combined with an anti-PD-1 agent. CONCLUSION: The immune checkpoint ligand B7-H4 is a promising molecular target expressed by multiple solid tumors. SGN-B7H4V demonstrates robust antitumor activity in preclinical models through multiple potential mechanisms. Altogether, these preclinical data support the evaluation of SGN-B7H4V as a monotherapy in the ongoing phase 1 study of SGN-B7H4V in advanced solid tumors (NCT05194072) and potential future clinical combinations with immunotherapies.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Animales , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Línea Celular Tumoral , Modelos Animales de Enfermedad , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Inmunoconjugados/química , Inmunohistoquímica , Ligandos
12.
J Biol Chem ; 286(20): 17682-92, 2011 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-21454712

RESUMEN

Previous studies have suggested that the BH3 domain of the proapoptotic Bcl-2 family member Noxa only interacts with the anti-apoptotic proteins Mcl-1 and A1 but not Bcl-2. In view of the similarity of the BH3 binding domains of these anti-apoptotic proteins as well as recent evidence that studies of isolated BH3 domains can potentially underestimate the binding between full-length Bcl-2 family members, we examined the interaction of full-length human Noxa with anti-apoptotic human Bcl-2 family members. Surface plasmon resonance using bacterially expressed proteins demonstrated that Noxa binds with mean dissociation constants (K(D)) of 3.4 nm for Mcl-1, 70 nm for Bcl-x(L), and 250 nm for wild type human Bcl-2, demonstrating selectivity but not absolute specificity of Noxa for Mcl-1. Further analysis showed that the Noxa/Bcl-2 interaction reflected binding between the Noxa BH3 domain and the Bcl-2 BH3 binding groove. Analysis of proteins expressed in vivo demonstrated that Noxa and Bcl-2 can be pulled down together from a variety of cells. Moreover, when compared with wild type Bcl-2, certain lymphoma-derived Bcl-2 mutants bound Noxa up to 20-fold more tightly in vitro, pulled down more Noxa from cells, and protected cells against killing by transfected Noxa to a greater extent. When killing by bortezomib (an agent whose cytotoxicity in Jurkat T-cell leukemia cells is dependent on Noxa) was examined, apoptosis was enhanced by the Bcl-2/Bcl-x(L) antagonist ABT-737 or by Bcl-2 down-regulation and diminished by Bcl-2 overexpression. Collectively, these observations not only establish the ability of Noxa and Bcl-2 to interact but also identify Bcl-2 overexpression as a potential mechanism of bortezomib resistance.


Asunto(s)
Antineoplásicos/farmacología , Ácidos Borónicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Linfocitos/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Pirazinas/farmacología , Apoptosis/efectos de los fármacos , Bortezomib , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Humanos , Células Jurkat , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas c-bcl-2/genética
13.
J Pharmacol Toxicol Methods ; 114: 107157, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35143957

RESUMEN

INTRODUCTION: Despite viral suppression due to combination antiretroviral therapy (cART), HIV-associated neurocognitive disorders (HAND) continue to affect half of people with HIV, suggesting that certain antiretrovirals (ARVs) may contribute to HAND. METHODS: We examined the effects of nucleoside/nucleotide reverse transcriptase inhibitors tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) and the integrase inhibitors dolutegravir (DTG) and elvitegravir (EVG) on viability, structure, and function of glutamatergic neurons (a subtype of CNS neuron involved in cognition) derived from human induced pluripotent stem cells (hiPSC-neurons), and primary human neural precursor cells (hNPCs), which are responsible for neurogenesis. RESULTS: Using automated digital microscopy and image analysis (high content analysis, HCA), we found that DTG, EVG, and TDF decreased hiPSC-neuron viability, neurites, and synapses after 7 days of treatment. Analysis of hiPSC-neuron calcium activity using Kinetic Image Cytometry (KIC) demonstrated that DTG and EVG also decreased the frequency and magnitude of intracellular calcium transients. Longer ARV exposures and simultaneous exposure to multiple ARVs increased the magnitude of these neurotoxic effects. Using the Microscopic Imaging of Epigenetic Landscapes (MIEL) assay, we found that TDF decreased hNPC viability and changed the distribution of histone modifications that regulate chromatin packing, suggesting that TDF may reduce neuroprogenitor pools important for CNS development and maintenance of cognition in adults. CONCLUSION: This study establishes human preclinical assays that can screen potential ARVs for CNS toxicity to develop safer cART regimens and HAND therapeutics.


Asunto(s)
Infecciones por VIH , Células Madre Pluripotentes Inducidas , Células-Madre Neurales , Adulto , Epigénesis Genética , Infecciones por VIH/tratamiento farmacológico , Humanos , Citometría de Imagen , Neuronas
14.
Sci Rep ; 12(1): 16860, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36258023

RESUMEN

Infection is the most common cause of mortality early in life, yet the broad potential of immunization is not fully realized in this vulnerable population. Most vaccines are administered during infancy and childhood, but in some cases the full benefit of vaccination is not realized in-part. New adjuvants are cardinal to further optimize current immunization approaches for early life. However, only a few classes of adjuvants are presently incorporated in vaccines approved for human use. Recent advances in the discovery and delivery of Toll-like receptor (TLR) agonist adjuvants have provided a new toolbox for vaccinologists. Prominent among these candidate adjuvants are synthetic small molecule TLR7/8 agonists. The development of an effective infant Bordetella pertussis vaccine is urgently required because of the resurgence of pertussis in many countries, contemporaneous to the switch from whole cell to acellular vaccines. In this context, TLR7/8 adjuvant based vaccine formulation strategies may be a promising tool to enhance and accelerate early life immunity by acellular B. pertussis vaccines. In the present study, we optimized (a) the formulation delivery system, (b) structure, and (c) immunologic activity of novel small molecule imidazoquinoline TLR7/8 adjuvants towards human infant leukocytes, including dendritic cells. Upon immunization of neonatal mice, this TLR7/8 adjuvant overcame neonatal hyporesponsiveness to acellular pertussis vaccination by driving a T helper (Th)1/Th17 biased T cell- and IgG2c-skewed humoral response to a licensed acellular vaccine (DTaP). This potent immunization strategy may represent a new paradigm for effective immunization against pertussis and other pathogens in early life.


Asunto(s)
Tos Ferina , Animales , Niño , Humanos , Lactante , Ratones , Adyuvantes Inmunológicos/farmacología , Adyuvantes Farmacéuticos , Vacuna contra la Tos Ferina , Receptor Toll-Like 7/agonistas , Vacunación , Vacunas Acelulares , Tos Ferina/epidemiología
15.
Postgrad Med J ; 87(1024): 110-5, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21097545

RESUMEN

Heart failure is increasingly common in western populations and is an inevitable consequence of the improved survival after myocardial infarction, and of an ageing population. Heart failure is usually relentlessly progressive as the maladaptive processes triggered by the physiological changes of the condition lead to further deterioration. However, in certain circumstances, heart failure is transient or potentially reversible when it occurs as part of intense systemic inflammatory activation. This review considers the role of inflammation in the aetiology of heart failure, and illustrates the strategies which have been used to modify the inflammatory response with anonymised clinical case reports.


Asunto(s)
Insuficiencia Cardíaca/etiología , Inflamación/complicaciones , Infarto del Miocardio/complicaciones , Insuficiencia Cardíaca/fisiopatología , Humanos , Inflamación/fisiopatología , Infarto del Miocardio/fisiopatología
16.
Emerg Med J ; 28(8): 700-2, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20682955

RESUMEN

BACKGROUND: Mortality from acute myocardial infarction is influenced by the speed at which reperfusion therapy is delivered. In the U.K., prehospital thrombolysis (PHT), administered by paramedics, has been developed to improve call to needle (CTN) times. Recently, it has been shown in randomised trials that mortality can be further reduced by primary percutaneous coronary intervention (PPCI). This project was developed to assess current ST-elevation myocardial infarction practice in a district general hospital and to prepare paramedics for PPCI. METHODS: Data were collected prospectively over a 12-month period for all patients who received thrombolysis for a presumed myocardial infarct. The primary outcome measures for each case were who delivered the thrombolysis, either the paramedic crew or the hospital, and if the patient did not receive PHT the reason why not. Secondary outcome measures included the CTN time. RESULTS: 153 patients received thrombolysis over the time period (99 men, 54 women, mean age 66 ± 15 years). Of this group, 55 patients received PHT (35.9%) with a median CTN time of 36 min (inter-quartile range (IQR) 30-42 min). The commonest reason for exclusion from receiving PHT was that the patient's history did not fit the eligibility criteria (25% of cases). CONCLUSIONS: Paramedics are able to deliver PHT promptly and safely. With the focus now on PPCI, it is anticipated that not only will paramedics be able to select patients for delivery to a heart attack centre for PPCI, they will be selecting many more patients for this treatment than have up to now received PHT.


Asunto(s)
Servicios Médicos de Urgencia/métodos , Auxiliares de Urgencia , Infarto del Miocardio/terapia , Terapia Trombolítica , Anciano , Anciano de 80 o más Años , Competencia Clínica , Toma de Decisiones , Servicios Médicos de Urgencia/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Estudios Prospectivos , Factores de Tiempo , Reino Unido
17.
J Med Chem ; 63(1): 309-320, 2020 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-31809053

RESUMEN

Mycobacterium tuberculosis (Mtb) continues to be a major health threat worldwide, and the development of Mtb vaccines could play a pivotal role in the prevention and control of this devastating epidemic. Th17-mediated immunity has been implicated in disease protection correlates of immune protection against Mtb. Currently, there are no approved adjuvants capable of driving a Th17 response in a vaccine setting. Recent clinical trial results using trehalose dibehenate have demonstrated a formulation-dependant proof of concept adjuvant system CAF01 capable of inducing long-lived protection. We have discovered a new class of Th17-inducing vaccine adjuvants based on the natural product Brartemicin. We synthesized and evaluated the capacity of a library of aryl trehalose derivatives to drive immunostimulatory reresponses and evaluated the structure-activity relationships in terms of the ability to engage the Mincle receptor and induce production of innate cytokines from human and murine cells. We elaborated on the structure-activity relationship of the new scaffold and demonstrated the ability of the lead entity to induce a pro-Th17 cytokine profile from primary human peripheral blood mononuclear cells and demonstrated efficacy in generating antibodies in combination with tuberculosis antigen M72 in a mouse model.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Mycobacterium tuberculosis/efectos de los fármacos , Trehalosa/análogos & derivados , Adyuvantes Inmunológicos/síntesis química , Adyuvantes Inmunológicos/metabolismo , Animales , Sitios de Unión , Bovinos , Línea Celular , Femenino , Humanos , Lectinas Tipo C/agonistas , Lectinas Tipo C/metabolismo , Ratones Endogámicos BALB C , Simulación del Acoplamiento Molecular , Estructura Molecular , Receptores Inmunológicos/agonistas , Receptores Inmunológicos/metabolismo , Relación Estructura-Actividad , Trehalosa/síntesis química , Trehalosa/metabolismo , Trehalosa/uso terapéutico , Tuberculosis/terapia , Vacunas contra la Tuberculosis/uso terapéutico
18.
Front Immunol ; 10: 338, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30873180

RESUMEN

Despite the ever present need for an effective Mycobacterium tuberculosis (Mtb) vaccine, efforts for development have been largely unsuccessful. Correlates of immune protection against Mtb are not wholly defined, but Th1 and likely Th17 adaptive immune responses have been demonstrated to be necessary for vaccine-mediated protection. Unfortunately, no approved adjuvants are able to drive a Th17 response, though recent clinical trials with CAF01 have demonstrated proof of concept. Herein we present the discovery and characterization of a new class of potential Th17-inducing vaccine adjuvants, alpha-branched trehalose diester molecules (αTDE). Based off the Mtb immunostimulatory component trehalose dimycolate (TDM), we synthesized and evaluated the immunostimulatory capacity of a library of structural derivatives. We evaluated the structure activity relationship of the compounds in relation to chain length and engagement of the Mincle receptor, production of innate cytokines from human and murine cells, and a pro-Th17 cytokine profile from primary human peripheral blood mononuclear cells. Murine cells displayed more structural tolerance, engaging and responding to a wide array of compound chain lengths. Interestingly, human cells displayed a unique specificity for ester chains between 5 and 14 carbons for maximal immune stimulating activity. Evaluation of two distinct αTDEs, B16 and B42, in concert with a recombinant Mtb antigen demonstrated their ability to augment a Th17 immune response against a Mtb antigen in vivo. Collectively this data describes the species-specific structural requirements for maximal human activity of alpha-branched trehalose diester compounds and demonstrates their capacity to serve as potent Th17-inducing adjuvants.


Asunto(s)
Factores Cordón/química , Factores Cordón/inmunología , Trehalosa/química , Trehalosa/inmunología , Adyuvantes Inmunológicos , Animales , Línea Celular , Citocinas/metabolismo , Humanos , Inmunidad Celular , Lectinas Tipo C , Ratones , Estructura Molecular , Mycobacterium tuberculosis/inmunología , Relación Estructura-Actividad , Células Th17/inmunología , Células Th17/metabolismo
19.
Am J Infect Control ; 47(1): e7-e14, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30612611

RESUMEN

BACKGROUND: Healthcare-associated Clostridium difficile infection (CDI) in pregnant/postpartum women is underreported, especially outside of North America. We report a cluster of cases in 2 neighboring secondary care hospitals in South-East England. The objective of this study was to identify the epidemiology and risk factors for infection. METHODS: An investigation into a cluster of cases of confirmed CDI in pregnant/postpartum women was performed over a 12-month period, from June 2016 to June 2017. RESULTS: Eleven cases, in 10 patients, were identified, including 1 patient who had a relapse. Eight of 10 patients developed symptoms after hospital discharge. All patients had received broad-spectrum antibiotics prior to CDI onset. Environmental vectors, such as labor room mattresses, that were found difficult to effectively decontaminate after heavy contamination with blood, feces, and other body fluids may have been possible reservoirs. An infection control care bundle was successful in preventing further cases. CONCLUSIONS: Antibiotic use and exposure to the organism in a contaminated labor room environment are likely risk factors for healthcare-associated CDI in postpartum women. Active surveillance is necessary to prevent these infections, as these cases often present after hospital discharge.


Asunto(s)
Infecciones por Clostridium/epidemiología , Infección Hospitalaria/epidemiología , Periodo Posparto , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Antibacterianos/uso terapéutico , Análisis por Conglomerados , Inglaterra/epidemiología , Exposición a Riesgos Ambientales , Femenino , Hospitales , Humanos , Embarazo , Recurrencia , Factores de Riesgo
20.
Methods Mol Biol ; 1698: 205-228, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29076092

RESUMEN

During erythropoiesis, erythroblasts undergo dramatic morphological changes to produce mature erythrocytes. Many unanswered questions regarding the molecular mechanisms behind these changes can be addressed with high-resolution fluorescence imaging. Immunofluoresence staining enables localization of specific molecules, organelles, and membrane components in intact cells at different phases of erythropoiesis. Confocal laser scanning microscopy can provide high-resolution, three-dimensional images of stained structures, which can be used to dissect the molecular mechanisms driving erythropoiesis. The sample preparation, staining procedure, imaging parameters, and image analysis methods used directly affect the quality of the confocal images and the amount and accuracy of information that they can provide. Here, we describe methods to dissect erythropoietic tissues from mice, to perform immunofluorescence staining and confocal imaging of various molecules, organelles and structures of interest in erythroblasts, and to present and quantitatively analyze the data obtained in these fluorescence images.


Asunto(s)
Eritroblastos/citología , Eritroblastos/metabolismo , Técnica del Anticuerpo Fluorescente , Microscopía Fluorescente , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Eritrocitos/citología , Eritrocitos/metabolismo , Eritropoyesis , Femenino , Feto , Procesamiento de Imagen Asistido por Computador , Hígado/citología , Ratones , Microscopía Confocal , Microscopía Fluorescente/métodos , Embarazo
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