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1.
Transfusion ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884364

RESUMEN

BACKGROUND: Blood collection from donors on testosterone therapy (TT) is restricted to red blood cell (RBC) concentrates to avoid patient exposure to supraphysiological testosterone (T). The objective of this study was to identify TT-related changes in RBC characteristics relevant to transfusion effectiveness in patients. STUDY DESIGN: This was a two-part study with cohorts of patients and blood donors on TT. In part 1, we conducted longitudinal evaluation of RBCs collected before and at three time points after initiation of T. RBC assays included storage and oxidative hemolysis, membrane deformability (elongation index), and oximetry. In part 2, we evaluated the fate of transfused RBCs from TT donors in immunodeficient mice and by retrospective analyses of NIH's vein-to-vein databases. RESULTS: TT increased oxidative hemolysis (1.45-fold change) and decreased RBC membrane deformability. Plasma free testosterone was positively correlated with oxidative hemolysis (r = .552) and negatively correlated with the elongation index (r = -.472). Stored and gamma-irradiated RBCs from TT donors had lower posttransfusion recovery in mice compared to controls (41.6 ± 12 vs. 55.3 ± 20.5%). Recipients of RBCs from male donors taking T had 25% lower hemoglobin increments compared to recipients of RBCs from non-TT male donors, and had increased incidence (OR, 1.80) of requiring additional RBC transfusions within 48 h of the index transfusion event. CONCLUSIONS: TT is associated with altered RBC characteristics and transfusion effectiveness. These results suggest that clinical utilization of TT RBCs may be less effective in recipients who benefit from longer RBC survival, such as chronically transfused patients.

2.
Psychooncology ; 33(3): e6315, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38423988

RESUMEN

BACKGROUND: Retinoblastoma is a rare childhood ophthalmic cancer that requires frequent eye examinations under anaesthesia and painful or distressing procedures. This can cause significant anxiety for children and their families. OBJECTIVE: We evaluated a Starlight Children's Foundation programme, 'Captains on Call', at the Queensland Children's Hospital, which aims to provide positive distraction and reduce stress, anxiety and pain during the perioperative journey for children in the retinoblastoma treatment pathway. This study examined the impact of the programme on the perioperative experience of the children and their families, using a qualitative design. METHODS: This study was conducted in a paediatric operating suite at a tertiary-level children's hospital in Australia. We interviewed a parent from 20 families (from a cohort of 40 families, including 44 children), whose children received treatment or screening for retinoblastoma, focusing on the programme's impact on the child and family at various stages during the perioperative journey. We undertook a thematic analysis of transcribed interviews. RESULTS: We identified two themes, each with two sub-themes: (1) the programme positively contributed to the overall treatment journey, by addressing different needs at different times, and helping to reframe a traumatic medical experience, and (2), the programme supported the whole family unit by empowering children through play, and adopting a family systems approach which recognised the impact of cancer treatment on the whole family. CONCLUSION: This study highlights the value of the Captains on Call programme in supporting children with retinoblastoma and their families during perioperative visits. The Captains, particularly as non-medicalised professionals in a healthcare setting, built trust and rapport with the children through play over repeated episodes of care. The interprofessional collaborative approach with a reflective cycle of practice extended it beyond a programme providing simple distraction. Other retinoblastoma services may benefit from implementing a similar approach.


Asunto(s)
Neoplasias de la Retina , Retinoblastoma , Niño , Humanos , Retinoblastoma/diagnóstico , Retinoblastoma/terapia , Padres , Dolor , Ansiedad , Neoplasias de la Retina/diagnóstico , Neoplasias de la Retina/terapia
3.
J Immunol ; 204(1): 49-57, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31740487

RESUMEN

The control of cytoskeletal dynamics by dedicator of cytokinesis 2 (DOCK2), a hematopoietic cell-specific actin effector protein, has been implicated in TCR signaling and T cell migration. Biallelic mutations in Dock2 have been identified in patients with a recessive form of combined immunodeficiency with defects in T, B, and NK cell activation. Surprisingly, we show in this study that certain immune functions of CD8+ T cells are enhanced in the absence of DOCK2. Dock2-deficient mice have a pronounced expansion of their memory T cell compartment. Bone marrow chimera and adoptive transfer studies indicate that these memory T cells develop in a cell-intrinsic manner following thymic egress. Transcriptional profiling, TCR repertoire analyses, and cell surface marker expression indicate that Dock2-deficient naive CD8+ T cells directly convert into virtual memory cells without clonal effector T cell expansion. This direct conversion to memory is associated with a selective increase in TCR sensitivity to self-peptide MHC in vivo and an enhanced response to weak agonist peptides ex vivo. In contrast, the response to strong agonist peptides remains unaltered in Dock2-deficient T cells. Collectively, these findings suggest that the regulation of the actin dynamics by DOCK2 enhances the threshold for entry into the virtual memory compartment by negatively regulating tonic TCR triggering in response to weak agonists.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Proteínas Activadoras de GTPasa/inmunología , Factores de Intercambio de Guanina Nucleótido/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Animales , Proteínas de Homeodominio/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos
4.
Transfusion ; 61(2): 435-448, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33146433

RESUMEN

BACKGROUND: Obesity is a global pandemic characterized by multiple comorbidities, including cardiovascular and metabolic diseases. The aim of this study was to define the associations between blood donor body mass index (BMI) and RBC measurements of metabolic stress and hemolysis. STUDY DESIGN AND METHODS: The associations between donor BMI (<25 kg/m2 , normal weight; 25-29.9 kg/m2 , overweight; and ≥30 kg/m2 , obese) and hemolysis (storage, osmotic, and oxidative; n = 18 donors) or posttransfusion recovery (n = 14 donors) in immunodeficient mice were determined in stored leukocyte-reduced RBC units. Further evaluations were conducted using the National Heart, Lung, and Blood Institute RBC-Omics blood donor databases of hemolysis (n = 13 317) and metabolomics (n = 203). RESULTS: Evaluations in 18 donors revealed that BMI was significantly (P < 0.05) and positively associated with storage and osmotic hemolysis. A BMI of 30 kg/m2 or greater was also associated with lower posttransfusion recovery in mice 10 minutes after transfusion (P = 0.026). Multivariable linear regression analyses in RBC-Omics revealed that BMI was a significant modifier for all hemolysis measurements, explaining 4.5%, 4.2%, and 0.2% of the variance in osmotic, oxidative, and storage hemolysis, respectively. In this cohort, obesity was positively associated (P < 0.001) with plasma ferritin (inflammation marker). Metabolomic analyses on RBCs from obese donors (44.1 ± 5.1 kg/m2 ) had altered membrane lipid composition, dysregulation of antioxidant pathways (eg, increased oxidized lipids, methionine sulfoxide, and xanthine), and dysregulation of nitric oxide metabolism, as compared to RBCs from nonobese (20.5 ± 1.0 kg/m2 ) donors. CONCLUSIONS: Obesity is associated with significant changes in RBC metabolism and increased susceptibility to hemolysis under routine storage of RBC units. The impact on transfusion efficacy warrants further evaluation.


Asunto(s)
Donantes de Sangre , Conservación de la Sangre/métodos , Eritrocitos/metabolismo , Obesidad/sangre , Adulto , Animales , Índice de Masa Corporal , Frío , Membrana Eritrocítica/química , Transfusión de Eritrocitos , Eritrocitos/citología , Femenino , Ferritinas/sangre , Pruebas Hematológicas , Hemólisis/fisiología , Humanos , Procedimientos de Reducción del Leucocitos , Masculino , Lípidos de la Membrana/sangre , Metaboloma , Ratones , Ratones Endogámicos NOD , Óxido Nítrico/sangre , Presión Osmótica , Estrés Oxidativo
5.
Transfusion ; 59(11): 3501-3510, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31599981

RESUMEN

BACKGROUND: Alloimmunization to platelet-rich plasma (PRP) transfusions can cause adverse reactions such as platelet refractoriness or transplant rejection. Pathogen reduction treatment with ultraviolet light and riboflavin (UV + R) of allogeneic PRP was shown to reduce allogeneic antibody responses and confer partial antigen-specific immune tolerance to subsequent transfusions in mice. Studies have shown that UV + R was effective at both rapidly killing donor white blood cells (WBCs) and reducing their ability to stimulate an allogeneic response in vitro. However, the manner in which UV + R induces WBC death and its associated role in the immune response to treated PRP is unknown. METHODS AND MATERIALS: This study evaluates whether UV + R causes WBC apoptosis by examining phosphatidylserine exposure on the plasma membrane, membrane asymmetry, caspase activity, and chromatin condensation by flow cytometry. The immunogenicity of WBCs killed with UV + R versus apoptotic or necrotic pathways was also examined in vivo. RESULTS: WBCs after UV + R exhibited early apoptotic-like characteristics including phosphatidylserine exposure on the outer leaflet of the plasma membrane and loss of membrane asymmetry, but unlike canonical apoptotic cells, caspase activity and chromatin condensation were not apparent. However, in vivo studies demonstrated, unlike untreated or necrotic WBCs, both apoptotic WBCs and UV + R-treated WBCs failed to prime alloantibody responses to subsequent untreated transfusions. CONCLUSION: Overall, the mechanism of WBC death following UV + R treatment shares some membrane characteristics of early apoptosis but is distinct from classic apoptosis. Despite these differences, UV + R-treated and apoptotic WBCs both offer some protection from alloimmunization.


Asunto(s)
Apoptosis/efectos de los fármacos , Seguridad de la Sangre/métodos , Leucocitos/efectos de los fármacos , Fármacos Fotosensibilizantes/farmacología , Riboflavina/farmacología , Reacción a la Transfusión/prevención & control , Rayos Ultravioleta , Animales , Biomarcadores/metabolismo , Femenino , Citometría de Flujo , Humanos , Tolerancia Inmunológica , Leucocitos/inmunología , Leucocitos/metabolismo , Leucocitos/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Fármacos Fotosensibilizantes/administración & dosificación , Transfusión de Plaquetas/métodos , Plasma Rico en Plaquetas/citología , Plasma Rico en Plaquetas/inmunología , Riboflavina/administración & dosificación
6.
Vox Sang ; 114(3): 207-215, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30734299

RESUMEN

BACKGROUND AND OBJECTIVES: Alloimmunization is common following transfusion with platelet-rich plasma (PRP) and can cause complications such as platelet refractoriness or transplant rejection. It has previously been shown that pathogen reduction of PRP with riboflavin and UV light (UV+R) can protect against alloimmunization in mice and induce partial tolerance to subsequent transfusions. MATERIALS AND METHODS: Using B6 H2d congenic mice, this study evaluated the relative contributions of major histocompatibility complex (MHC) antigens and minor antigens to both the alloresponse to PRP transfusion and the partial tolerance induced by UV+R treatment. RESULTS: Both total and MHC-specific alloantibody responses were highest when both MHC and minor antigens were mismatched, with lower alloantibody responses observed with MHC mismatch alone, demonstrating that allogeneic minor antigens can enhance the response to allogeneic MHC. There was a weak, but significant alloantibody response to minor antigens only. UV+R treatment protected against both major and minor antigen alloimmunization. Both allogeneic MHC and minor antigens primed an enhanced cytokine response ex vivo, though this was weaker with minor antigens, and both responses were blocked with UV+R treatment. CONCLUSION: Allogeneic MHC is both necessary and sufficient to induce the partial tolerance associated with UV+R treatment.


Asunto(s)
Plaquetas/inmunología , Tolerancia Inmunológica , Complejo Mayor de Histocompatibilidad/inmunología , Transfusión de Plaquetas/métodos , Animales , Plaquetas/efectos de los fármacos , Plaquetas/efectos de la radiación , Isoanticuerpos/inmunología , Ratones , Ratones Endogámicos BALB C , Transfusión de Plaquetas/efectos adversos , Riboflavina/farmacología , Rayos Ultravioleta
7.
Eukaryot Cell ; 12(7): 1009-19, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23687115

RESUMEN

SAS-6 is required for centriole biogenesis in diverse eukaryotes. Here, we describe a novel family of SAS-6-like (SAS6L) proteins that share an N-terminal domain with SAS-6 but lack coiled-coil tails. SAS6L proteins are found in a subset of eukaryotes that contain SAS-6, including diverse protozoa and green algae. In the apicomplexan parasite Toxoplasma gondii, SAS-6 localizes to the centriole but SAS6L is found above the conoid, an enigmatic tubulin-containing structure found at the apex of a subset of alveolate organisms. Loss of SAS6L causes reduced fitness in Toxoplasma. The Trypanosoma brucei homolog of SAS6L localizes to the basal-plate region, the site in the axoneme where the central-pair microtubules are nucleated. When endogenous SAS6L is overexpressed in Toxoplasma tachyzoites or Trypanosoma trypomastigotes, it forms prominent filaments that extend through the cell cytoplasm, indicating that it retains a capacity to form higher-order structures despite lacking a coiled-coil domain. We conclude that although SAS6L proteins share a conserved domain with SAS-6, they are a functionally distinct family that predates the last common ancestor of eukaryotes. Moreover, the distinct localization of the SAS6L protein in Trypanosoma and Toxoplasma adds weight to the hypothesis that the conoid complex evolved from flagellar components.


Asunto(s)
Evolución Biológica , Flagelos/metabolismo , Proteínas Protozoarias/metabolismo , Toxoplasma/metabolismo , Citoesqueleto de Actina/metabolismo , Axonema/metabolismo , Axonema/ultraestructura , Cilios/metabolismo , Flagelos/ultraestructura , Transporte de Proteínas , Proteínas Recombinantes de Fusión/metabolismo , Toxoplasma/ultraestructura
8.
Eukaryot Cell ; 11(2): 206-16, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22021240

RESUMEN

We have identified two novel proteins that colocalize with the subpellicular microtubules in the protozoan parasite Toxoplasma gondii and named these proteins SPM1 and SPM2. These proteins have basic isoelectric points and both have homologs in other apicomplexan parasites. SPM1 contains six tandem copies of a 32-amino-acid repeat, whereas SPM2 lacks defined protein signatures. Alignment of Toxoplasma SPM2 with apparent Plasmodium SPM2 homologs indicates that the greatest degree of conservation lies in the carboxy-terminal half of the protein. Analysis of Plasmodium homologs of SPM1 indicates that while the central 32-amino-acid repeats have expanded to different degrees (7, 8, 9, 12, or 13 repeats), the amino- and carboxy-terminal regions remain conserved. In contrast, although the Cryptosporidium SPM1 homolog has a conserved carboxy tail, the five repeats are considerably diverged, and it has a smaller amino-terminal domain. SPM1 is localized along the full length of the subpellicular microtubules but does not associate with the conoid or spindle microtubules. SPM2 has a restricted localization along the middle region of the subpellicular microtubules. Domain deletion analysis indicates that four or more copies of the SPM1 repeat are required for localization to microtubules, and the amino-terminal 63 residues of SPM2 are required for localization to the subpellicular microtubules. Gene deletion studies indicate that neither SPM1 nor SPM2 is essential for tachyzoite viability. However, loss of SPM1 decreases overall parasite fitness and eliminates the stability of subpellicular microtubules to detergent extraction.


Asunto(s)
Microtúbulos/metabolismo , Proteínas Protozoarias/metabolismo , Toxoplasma/metabolismo , Secuencia de Aminoácidos , Células Cultivadas , Humanos , Datos de Secuencia Molecular , Proteínas Protozoarias/genética , Alineación de Secuencia , Secuencias Repetidas en Tándem , Tubulina (Proteína)/metabolismo
9.
Front Immunol ; 14: 1281123, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38090570

RESUMEN

Introduction: Alloimmunization is common following platelet transfusion and can result in negative outcomes for recipients such as refractoriness to subsequent transfusions and rejection of transplants. Healthy people do not receive blood transfusions, and the diseases and therapies that result in a need to transfuse have significant impacts on the immunological environment to which these alloantigens are introduced. Ablative chemotherapies are common among platelet recipients and have potent immunological effects. In this study, we modeled the impact of chemotherapy on the alloresponse to platelet transfusion. As chemotherapies are generally regarded as immunosuppressive, we hypothesized that that they would result in a diminished alloresponse. Methods: Mice were given a combination chemotherapeutic treatment of cytarabine and doxorubicin followed by transfusion of allogeneic platelets, and compared to controls given no treatment, chemotherapy alone, or transfusion alone. Alloantibody responses were measured 2 weeks after transfusion, and cellular responses and growth factors were monitored over time. Results: Contrary to our hypothesis, we found that chemotherapy led to increased alloantibody responses to allogeneic platelet transfusion. This enhanced response was antigen-specific and was associated with increased CD4+ and CD8+ T cell responses. Chemotherapy led to rapid lymphocyte depletion followed by reconstitution, non-specific activation of transitional B cells with the highest levels of activation in the least mature subsets, and increased serum levels of B cell activating factor (BAFF). Conclusion: These data suggest that ablative chemotherapy can increase the risk of alloimmunization and, if confirmed clinically, that additional measures to protect these patient populations may be warranted.


Asunto(s)
Plaquetas , Transfusión de Plaquetas , Ratones , Humanos , Animales , Transfusión de Plaquetas/efectos adversos , Transfusión Sanguínea , Isoanticuerpos , Interleucina-4
10.
Front Immunol ; 14: 1281130, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38146372

RESUMEN

Introduction: Alloimmune responses against platelet antigens, which dominantly target the major histocompatibility complex (MHC), can cause adverse reactions to subsequent platelet transfusions, platelet refractoriness, or rejection of future transplants. Platelet transfusion recipients include individuals experiencing severe bacterial or viral infections, and how their underlying health modulates platelet alloimmunity is not well understood. Methods: This study investigated the effect of underlying inflammation on platelet alloimmunization by modelling viral-like inflammation with polyinosinic-polycytidylic acid (poly(I:C)) or gram-negative bacterial infection with lipopolysaccharide (LPS), hypothesizing that underlying inflammation enhances alloimmunization. Mice were pretreated with poly(I:C), LPS, or nothing, then transfused with non-leukoreduced or leukoreduced platelets. Alloantibodies and allogeneic MHC-specific B cell (allo-B cell) responses were evaluated two weeks later. Rare populations of allo-B cells were identified using MHC tetramers. Results: Relative to platelet transfusion alone, prior exposure to poly(I:C) increased the alloantibody response to allogeneic platelet transfusion whereas prior exposure to LPS diminished responses. Prior exposure to poly(I:C) had equivalent, if not moderately diminished, allo-B cell responses relative to platelet transfusion alone and exhibited more robust allo-B cell memory development. Conversely, prior exposure to LPS resulted in diminished allo-B cell frequency, activation, antigen experience, and germinal center formation and altered memory B cell responses. Discussion: In conclusion, not all inflammatory environments enhance bystander responses and prior inflammation mediated by LPS on gram-negative bacteria may in fact curtail platelet alloimmunization.


Asunto(s)
Lipopolisacáridos , Transfusión de Plaquetas , Ratones , Animales , Transfusión de Plaquetas/efectos adversos , Lipopolisacáridos/farmacología , Poli C , Ratones Endogámicos BALB C , Antígenos de Histocompatibilidad , Inflamación/etiología , Poli I-C/farmacología
11.
Br J Psychiatry ; 198(1): 51-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21200077

RESUMEN

BACKGROUND: There is a need for a rapid-acting, non-injection, acute treatment for agitation. AIMS: To evaluate inhaled loxapine for acute treatment of agitation in schizophrenia. METHOD: This phase III, randomised, double-blind, placebo-controlled, parallel-group study (ClinicalTrials.gov number NCT00628589) enrolled 344 individuals who received one, two or three doses of inhaled loxapine (5 or 10 mg) or a placebo. Lorazepam rescue was permitted after dose two. The primary efficacy end-point was change from baseline in Positive and Negative Syndrome Scale-Excited Component (PANSS-EC) 2 h after dose one. The key secondary end-point was Clinical Global Impression-Improvement scale (CGI-I) score 2 h after dose one. RESULTS: Inhaled loxapine (5 and 10 mg) significantly reduced agitation compared with placebo as assessed by primary and key secondary end-points. Reduced PANSS-EC score was evident 10 min after dose one with both 5 and 10 mg doses. Inhaled loxapine was well tolerated, and the most common adverse events were known effects of loxapine or minor oral effects common with inhaled medications. CONCLUSIONS: Inhaled loxapine provided a rapid, well-tolerated acute treatment for agitation in people with schizophrenia.


Asunto(s)
Antipsicóticos/administración & dosificación , Loxapina/administración & dosificación , Agitación Psicomotora/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Enfermedad Aguda , Administración por Inhalación , Adolescente , Adulto , Anciano , Antipsicóticos/efectos adversos , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Estimación de Kaplan-Meier , Loxapina/efectos adversos , Masculino , Persona de Mediana Edad , Placebos , Escalas de Valoración Psiquiátrica , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
12.
Antimicrob Agents Chemother ; 54(4): 1453-60, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20145086

RESUMEN

The human parasite Toxoplasma gondii is sensitive to dinitroaniline compounds which selectively disrupt microtubules in diverse protozoa but which have no detectable effect on vertebrate host cell microtubules or other functions. Replication of wild-type T. gondii is inhibited by 0.5 to 2.5 microM oryzalin, but mutant parasites harboring amino acid substitutions in the predicted dinitroaniline binding site confer resistance up to 40 microM oryzalin. However, the precise interaction between dinitroanilines and the binding site in alpha-tubulin remains unclear. We have investigated the activity of 12 dinitroanilines and the related compound amiprophos methyl on wild-type and dinitroaniline-resistant parasite lines that contain proposed binding site mutations. These data indicate that dinitramine is the most effective dinitroaniline to inhibit Toxoplasma growth in wild-type parasites and most resistant lines. Dinitramine has an amine group at the meta position not present in any of the other dinitroanilines tested here that is predicted to form hydrogen bonds with residues Arg2 and Gln133 according to docking data. Remarkably, although the binding site mutation Ile235Val confers increased resistance to most dinitroanilines, it confers increased sensitivity to GB-II-5, a compound optimized for activity against kinetoplastid tubulin. Kinetoplastid parasites have a valine at position 235 of alpha-tubulin, whereas apicomplexan parasites have an isoleucine at this site. We suggest that this heterogeneity in binding site environment influences relative dinitroaniline sensitivity in distinct protozoan lineages and hypothesize that a mutation that makes the apicomplexan dinitroaniline binding site more like the kinetoplastid site increases sensitivity to a dinitroaniline optimized for activity in the latter parasites.


Asunto(s)
Compuestos de Anilina/farmacología , Coccidiostáticos/farmacología , Proteínas Protozoarias/genética , Toxoplasma/efectos de los fármacos , Toxoplasma/genética , Tubulina (Proteína)/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Compuestos de Anilina/química , Compuestos de Anilina/farmacocinética , Animales , Sitios de Unión/genética , Coccidiostáticos/química , Coccidiostáticos/farmacocinética , Resistencia a Medicamentos/genética , Humanos , Enlace de Hidrógeno , Técnicas In Vitro , Modelos Moleculares , Datos de Secuencia Molecular , Pruebas de Sensibilidad Parasitaria , Mutación Puntual , Proteínas Protozoarias/química , Proteínas Protozoarias/metabolismo , Homología de Secuencia de Aminoácido , Toxoplasma/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
13.
Blood Adv ; 4(21): 5547-5561, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33166410

RESUMEN

Alloimmunization against platelet-rich plasma (PRP) transfusions can lead to complications such as platelet refractoriness or rejection of subsequent transfusions and transplants. In mice, pathogen reduction treatment of PRP with UVB light and riboflavin (UV+R) prevents alloimmunization and appears to induce partial antigen-specific tolerance to subsequent transfusions. Herein, the in vivo responses of antigen-presenting cells and T cells to transfusion with UV+R-treated allogeneic PRP were evaluated to understand the cellular immune responses leading to antigen-specific tolerance. Mice that received UV+R-treated PRP had significantly increased transforming growth factor ß (TGF-ß) expression by CD11b+ CD4+ CD11cHi conventional dendritic cells (cDCs) and CD11bHi monocytes (P < .05). While robust T-cell responses to transfusions with untreated allogeneic PRP were observed (P < .05), these were blocked by UV+R treatment. Mice given UV+R-treated PRP followed by untreated PRP showed an early significant (P < .01) enrichment in regulatory T (Treg) cells and associated TGF-ß production as well as diminished effector T-cell responses. Adoptive transfer of T-cell-enriched splenocytes from mice given UV+R-treated PRP into naive recipients led to a small but significant reduction of CD8+ T-cell responses to subsequent allogeneic transfusion. These data demonstrate that pathogen reduction with UV+R induces a tolerogenic profile by way of CD11b+ CD4+ cDCs, monocytes, and induction of Treg cells, blocking T-cell activation and reducing secondary T-cell responses to untreated platelets in vivo.


Asunto(s)
Plasma Rico en Plaquetas , Linfocitos T Reguladores , Animales , Tolerancia Inmunológica , Ratones , Monocitos , Factor de Crecimiento Transformador beta
14.
PLoS One ; 15(7): e0237106, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32735605

RESUMEN

Animal models are vital to the study of transfusion and development of new blood products. Post-transfusion recovery of human blood components can be studied in mice, however, there is a need to identify strains that can best tolerate xenogeneic transfusions, as well as to optimize such protocols. Specifically, the importance of using immunodeficient mice, such as NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice, to study human transfusion has been questioned. In this study, strains of wild-type and NSG mice were compared as hosts for human transfusions with outcomes quantified by flow cytometric analyses of CD235a+ erythrocytes, CD45+ leukocytes, and CD41+CD42b+ platelets. Complete blood counts were evaluated as well as serum cytokines by multiplexing methods. Circulating human blood cells were maintained better in NSG than in wild-type mice. Lethargy and hemoglobinuria were observed in the first hours in wild-type mice along with increased pro-inflammatory cytokines/chemokines such as monocyte chemoattractant protein-1, tumor necrosis factor α, keratinocyte-derived chemokine (KC or CXCL1), and interleukin-6, whereas NSG mice were less severely affected. Whole blood transfusion resulted in rapid sequestration and then release of human cells back into the circulation within several hours. This rebound effect diminished when only erythrocytes were transfused. Nonetheless, human erythrocytes were found in excess of mouse erythrocytes in the liver and lungs and had a shorter half-life in circulation. Variables affecting the outcomes of transfused erythrocytes were cell dose and mouse weight; recipient sex did not affect outcomes. The sensitivity and utility of this xenogeneic model were shown by measuring the effects of erythrocyte damage due to exposure to the oxidizer diamide on post-transfusion recovery. Overall, immunodeficient mice are superior models for xenotransfusion as they maintain improved post-transfusion recovery with negligible immune-associated side effects.


Asunto(s)
Transfusión de Componentes Sanguíneos/métodos , Modelos Animales , Animales , Transfusión de Eritrocitos , Xenoinjertos , Humanos , Transfusión de Leucocitos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Transfusión de Plaquetas
15.
Genetics ; 180(2): 845-56, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18780736

RESUMEN

Dinitroanilines (oryzalin, trifluralin, ethafluralin) disrupt microtubules in protozoa but not in vertebrate cells, causing selective death of intracellular Toxoplasma gondii parasites without affecting host cells. Parasites containing alpha1-tubulin point mutations are dinitroaniline resistant but show increased rates of aberrant replication relative to wild-type parasites. T. gondii parasites bearing the F52Y mutation were previously demonstrated to spontaneously acquire two intragenic mutations that decrease both resistance levels and replication defects. Parasites bearing the G142S mutation are largely dependent on oryzalin for viable growth in culture. We isolated 46 T. gondii lines that have suppressed microtubule defects associated with the G142S or the F52Y mutations by acquiring secondary mutations. These compensatory mutations were alpha1-tubulin pseudorevertants or extragenic suppressors (the majority alter the beta1-tubulin gene). Many secondary mutations were located in tubulin domains that suggest that they function by destabilizing microtubules. Most strikingly, we identified seven novel mutations that localize to an eight-amino-acid insert that stabilizes the alpha1-tubulin M loop, including one (P364R) that acts as a compensatory mutation in both F52Y and G142S lines. These lines have reduced dinitroaniline resistance but most perform better than parental lines in competition assays, indicating that there is a trade-off between resistance and replication fitness.


Asunto(s)
Compuestos de Anilina/farmacología , Resistencia a Medicamentos/genética , Mutación , Toxoplasma/genética , Moduladores de Tubulina/farmacología , Tubulina (Proteína)/genética , Animales , Dinitrobencenos/farmacología , Técnica del Anticuerpo Fluorescente , Modelos Moleculares , Estructura Terciaria de Proteína , Sulfanilamidas/farmacología , Toxoplasma/metabolismo , Trifluralina/análogos & derivados , Trifluralina/farmacología , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
16.
Arch Intern Med ; 159(2): 174-81, 1999 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-9927101

RESUMEN

BACKGROUND: Patients with Sjögren syndrome (SS) experience slowly progressive infiltration of lacrimal and salivary glands by mononuclear cells. This leads to diminished secretions, with resultant symptoms of xerostomia and xerophthalmia. Although pilocarpine hydrochloride tablets are currently indicated for the treatment of radiation-induced xerostomia, their effects on dry mouth or dry eyes in patients with SS are unclear. OBJECTIVE: To assess the safety and efficacy of pilocarpine (Salagen) tablets as symptomatic treatment for dry mouth and dry eyes caused by SS in a multicenter, doubleblind, placebo-controlled trial. METHODS: After providing written informed consent, 373 patients with primary or secondary SS and clinically significant dry mouth and dry eyes were randomized to receive 2.5-mg pilocarpine, 5-mg pilocarpine, or placebo tablets 4 times daily for 12 weeks. Symptoms were assessed by questionnaires with visual analog scales or categorical checkboxes. Whole-mouth salivary flow rates were measured. RESULTS: A significantly greater proportion of patients in the 5-mg pilocarpine group showed improvement compared with the placebo group (P< or =.01) in global assessments of dry mouth, dry eyes, and other symptoms of dryness (P< or =.05). Salivary flow was significantly increased 2- to 3-fold (P<.001) after administration of the first dose and was maintained throughout the 12-week study. The most common adverse effect was sweating, and no serious drug-related adverse experiences were reported. CONCLUSION: Administration of 5-mg pilocarpine tablets 4 times daily (20 mg/d) was well tolerated and produced significant improvement in symptoms of dry mouth and dry eyes and other xeroses in patients with SS.


Asunto(s)
Parasimpaticomiméticos/uso terapéutico , Pilocarpina/uso terapéutico , Adulto , Anciano , Esquema de Medicación , Femenino , Humanos , Aparato Lagrimal/efectos de los fármacos , Masculino , Persona de Mediana Edad , Parasimpaticomiméticos/administración & dosificación , Parasimpaticomiméticos/efectos adversos , Pilocarpina/administración & dosificación , Pilocarpina/efectos adversos , Salivación/efectos de los fármacos , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/fisiopatología , Encuestas y Cuestionarios , Resultado del Tratamiento
17.
Am J Psychiatry ; 145(6): 748-50, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3285702

RESUMEN

Carbamazepine was given to 12 chronic, treatment-refractory schizophrenic patients for 5 weeks. No overall change was found, but four patients significantly improved while eight worsened. Given the paucity of successful treatments for refractory schizophrenia, further study of carbamazepine appears warranted.


Asunto(s)
Carbamazepina/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Adulto , Ensayos Clínicos como Asunto , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico
18.
Clin Geriatr Med ; 8(2): 401-10, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1350940

RESUMEN

Schizophrenia in late life includes both chronic early-onset schizophrenia and late-onset schizophrenia. Treatment with neuroleptics in relatively low doses is often useful in controlling psychotic symptoms in these patients. The value of neuroleptics is limited, however, by the risks of side effects such as tardive dyskinesia.


Asunto(s)
Envejecimiento/psicología , Antipsicóticos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Anciano , Envejecimiento/metabolismo , Antipsicóticos/farmacocinética , Antipsicóticos/farmacología , Humanos , Factores de Tiempo
19.
Am J Pharm Educ ; 77(10): 225, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24371349

RESUMEN

OBJECTIVE: To assess the effectiveness of the Student Leadership Development Series (SLDS), an academic-year--long, co-curricular approach to developing leadership skills in pharmacy students. DESIGN: Participants met once per month for activities and a college-wide guest speaker session. Students also completed monthly forms regarding what they had learned, participated in poster presentations, and created a personal leadership platform. ASSESSMENT: One hundred twenty-three students participated in the program between 2008 and 2013. On monthly evaluation forms and a summative evaluation, students indicated that the program helped them feel prepared for leadership opportunities and increased their desire to pursue leadership. They valued interacting with pharmacy leaders from the community and learning how they could distinguish themselves as leaders. CONCLUSIONS: The SLDS provided pharmacy students with an opportunity to explore personal leadership styles and develop broader understanding of leadership, and increased their desire to pursue leadership positions in the future.


Asunto(s)
Educación en Farmacia/organización & administración , Liderazgo , Estudiantes de Farmacia , Curriculum , Evaluación Educacional , Relaciones Interprofesionales , Desarrollo de Programa
20.
Cytoskeleton (Hoboken) ; 67(9): 586-98, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20658557

RESUMEN

The asexually proliferating stages of apicomplexan parasites cause acute symptoms of diseases such as malaria, cryptosporidiosis and toxoplasmosis. These stages are characterized by the presence of two independent microtubule organizing centers (MTOCs). Centrioles are found at the poles of the intranuclear spindle. The apical polar ring (APR), a MTOC unique to apicomplexans, organizes subpellicular microtubules which impose cell shape and apical polarity on these protozoa. Here we describe the characteristics of a novel protein that localizes to the APR of Toxoplasma gondii which we have named ring-1 (RNG1). There are related RNG1 proteins in Neospora caninum and Sarcocystis neurona but no obvious homologs in Plasmodium spp., Cryptosporidium spp. or Babesia spp. RNG1 is a small, low-complexity, detergent-insoluble protein that assembles at the APR very late in the process of daughter parasite replication. We were unable to knock-out the RNG1 gene, suggesting that its gene product is essential. Tagged RNG1 lines have also allowed us to visualize the APR during growth of Toxoplasma in the microtubule-disrupting drug oryzalin. Oryzalin inhibits nuclear division and cytokinesis although Toxoplasma growth continues, and similar to earlier observations of unchecked centriole duplication in oryzalin-treated parasites, the APR continues to duplicate during aberrant parasite growth.


Asunto(s)
Centro Organizador de los Microtúbulos/fisiología , Proteínas Protozoarias/genética , Toxoplasma/metabolismo , Animales , Neospora/metabolismo , Octoxinol/farmacología , Proteínas Protozoarias/efectos de los fármacos , Proteínas Protozoarias/metabolismo , Sarcocystis/metabolismo , Solubilidad
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