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INTRODUCTION: The aim of this study was to evaluate the adverse effects and immune response associated with IgG anti S1 SAEA-CoV-2 antibodies among healthcare workers at Señor del Milagro Hospital in Salta city, after receiving two doses of COVID-19 vaccine. METHODS: A prospective cohort study was carried out from March 2021 to April 2022. Demographic, clinical data, adverse events supposedly attributed to vaccination (AEFIs) were collected and two samples were taken to measure serum antibody levels. RESULTS: 408 volunteers participated, 401 (98%) were vaccinated with Sputnik-V. The average age was 45.5 years with a predominance of the female sex (71%). AEFIs were reported in 188 (46.1%) and 121 (29.7%) after the first and second doses respectively (p<0.001). These events were mostly mild and transient, more frequent after the first dose. The first antibody test was positive in 99% with a mean titer of 9.7 (SD 3.7). The second dosage was positive in 88% with a mean titer of 6.4 (SD 4.4). Participants with a history of infection and previous positive testing showed significantly higher antibody titers (p<0.001). CONCLUSION: The AEFIs reported were mostly mild and transient. Mass vaccination and administration of the recommended dose are essential to achieve effective herd immunity. The majority of vaccinated healthcare workers developed antibodies and those who had the disease prior to vaccination had significant antibody titers.
Introducción: El objetivo de este estudio fue evaluar los efectos adversos y la respuesta inmune de anticuerpos IgG anti S1 SAEA-CoV-2 en el personal de Salud del Hospital del Milagro de la ciudad de Salta, posterior a recibir dos dosis de vacuna COVID-19. Métodos: Se realizó un estudio prospectivo de cohorte desde marzo de 2021 hasta abril 2022. Se recopilaron datos demográficos, clínicos, eventos adversos supuestamente atribuidos a la vacunación (ESAVI) y se tomaron dos muestras de sangre para medir los niveles de anticuerpos. Resultados: Participaron 408 voluntarios, 401 (98%) fueron vacunados con Sputnik- V. La edad promedio fue de 45.5 años con predominio del sexo femenino (71%). Los ESAVI fueron reportados en 188 (46.1%) y 121 (29.7%) luego de la primera y segunda dosis respectivamente (p<0.001). Estos eventos fueron mayormente de carácter leve y transitorios, más frecuentes luego de la primera dosis. El primer dosaje de anticuerpos fue positivo en 99% con una media de títulos de 9.7 (SD 3.7). El segundo dosaje fue positivo en 88% con una media de títulos de 6.4 (SD 4.4). Los participantes con antecedentes de infección y dosajes previos positivos mostraron títulos significativamente más altos de anticuerpos (p<0.001). Conclusión: Los ESAVI reportados fueron mayoritariamente leves y transitorios. La vacunación masiva y la administración de la dosis recomendada son esenciales para lograr una inmunidad colectiva efectiva. La mayoría de los trabajadores de la salud vacunados desarrollaron anticuerpos y aquellos que cursaron la enfermedad previa a la vacunación presentaron títulos significativos más elevados de anticuerpos.
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Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Personal de Salud , SARS-CoV-2 , Humanos , Femenino , Masculino , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/efectos adversos , Personal de Salud/estadística & datos numéricos , Persona de Mediana Edad , Estudios Prospectivos , COVID-19/prevención & control , COVID-19/inmunología , Adulto , Anticuerpos Antivirales/sangre , SARS-CoV-2/inmunología , Inmunoglobulina G/sangre , Inmunogenicidad Vacunal/inmunologíaRESUMEN
Background: In September 2012, a comprehensive survey of Pico Island was conducted along an elevational transect, starting at Manhenha (10 m a.s.l.) and culminating at the Pico Mountain caldera (2200 m a.s.l.). The primary objective was to systematically inventory the bryophytes inhabiting the best-preserved areas of native vegetation environments. Twelve sites were selected, each spaced at 200 m elevation intervals. Within each site, two 10 m x 10 m plots were established in close proximity (10-15 m apart). Within these plots, three 2 m x 2 m quadrats were randomly selected and sampled for bryophytes using microplots measuring 10 cm x 5 cm, which were then collected into paper bags. Six substrates were surveyed in each quadrat: rock, soil, humus, organic matter, tree bark and leaves/fronds. Three replicates were obtained from all substrates available and colonised by bryophytes, resulting in a maximum of 18 microplots per quadrat, 54 microplots per plot, 108 microplots per site, and a total of 1296 microplots across the 12 sites on Pico Island. New information: Two-thirds of the maximum expected number of microplots (n = 878; 67.75%) were successfully collected, yielding a total of 4896 specimens. The vast majority (n = 4869) were identified at the species/subspecies level. The study identified a total of 70 moss and 71 liverwort species or subspecies. Elevation levels between 600-1000 m a.s.l., particularly in the native forest plots, exhibited both a higher number of microplots and greater species richness. This research significantly enhanced our understanding of Azorean bryophyte diversity and distribution, contributing valuable insights at both local and regional scales. Notably, two new taxa for the Azores were documented during the MOVECLIM study, namely the pleurocarpous mosses Antitrichiacurtipendula and Isotheciuminterludens.
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Sarcomas are a heterogenous group of tumours that commonly carry poor prognosis with limited therapeutic options. Adolescents and young adults (AYAs) with sarcoma are a unique and understudied patient population that have only achieved modest survival gains compared to other groups. We present our institutional experience of AYAs with sarcoma who underwent comprehensive molecular profiling (CMP) via either large-panel targeted DNA sequencing or whole genome and transcriptome sequencing and evaluated the feasibility and clinical impact of this approach. Genomic variants detected were determined to be clinically relevant and actionable following evaluation by the Molecular Tumour Board. Clinicians provided feedback regarding the utility of testing three months after reporting. Twenty-five patients who were recruited for CMP are included in this analysis. The median time from consent to final molecular report was 45 days (interquartile range: 37-57). Potentially actionable variants were detected for 14 patients (56%), and new treatment recommendations were identified for 12 patients (48%). Pathogenic germline variants were identified in three patients (12%), and one patient had a change in diagnosis. The implementation of CMP for AYAs with sarcoma is clinically valuable, feasible, and should be increasingly integrated into routine clinical practice as technologies and turnaround times continue to improve.
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BACKGROUND: Lung ultrasound (LUS) can detect pulmonary edema and it is under consideration to be added to updated acute respiratory distress syndrome (ARDS) criteria. However, it remains uncertain whether different LUS scores can be used to quantify pulmonary edema in patient with ARDS. OBJECTIVES: This study examined the diagnostic accuracy of four LUS scores with the extravascular lung water index (EVLWi) assessed by transpulmonary thermodilution in patients with moderate-to-severe COVID-19 ARDS. METHODS: In this predefined secondary analysis of a multicenter randomized-controlled trial (InventCOVID), patients were enrolled within 48 hours after intubation and underwent LUS and EVLWi measurement on the first and fourth day after enrolment. EVLWi and ∆EVLWi were used as reference standards. Two 12-region scores (global LUS and LUS-ARDS), an 8-region anterior-lateral score and a 4-region B-line score were used as index tests. Pearson correlation was performed and the area under the receiver operating characteristics curve (AUROCC) for severe pulmonary edema (EVLWi > 15 mL/kg) was calculated. RESULTS: 26 out of 30 patients (87%) had complete LUS and EVLWi measurements at time point 1 and 24 out of 29 patients (83%) at time point 2. The global LUS (r = 0.54), LUS-ARDS (r = 0.58) and anterior-lateral score (r = 0.54) correlated significantly with EVLWi, while the B-line score did not (r = 0.32). ∆global LUS (r = 0.49) and ∆anterior-lateral LUS (r = 0.52) correlated significantly with ∆EVLWi. AUROCC for EVLWi > 15 ml/kg was 0.73 for the global LUS, 0.79 for the anterior-lateral and 0.85 for the LUS-ARDS score. CONCLUSIONS: Overall, LUS demonstrated an acceptable diagnostic accuracy for detection of pulmonary edema in moderate-to-severe COVID-19 ARDS when compared with PICCO. For identifying patients at risk of severe pulmonary edema, an extended score considering pleural morphology may be of added value. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04794088, registered on 11 March 2021. European Clinical Trials Database number 2020-005447-23.
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PURPOSE: A hallmark of acute respiratory distress syndrome (ARDS) is hypoxaemic respiratory failure due to pulmonary vascular hyperpermeability. The tyrosine kinase inhibitor imatinib reversed pulmonary capillary leak in preclinical studies and improved clinical outcomes in hospitalized COVID-19 patients. We investigated the effect of intravenous (IV) imatinib on pulmonary edema in COVID-19 ARDS. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled trial. Invasively ventilated patients with moderate-to-severe COVID-19 ARDS were randomized to 200 mg IV imatinib or placebo twice daily for a maximum of seven days. The primary outcome was the change in extravascular lung water index (∆EVLWi) between days 1 and 4. Secondary outcomes included safety, duration of invasive ventilation, ventilator-free days (VFD) and 28-day mortality. Posthoc analyses were performed in previously identified biological subphenotypes. RESULTS: 66 patients were randomized to imatinib (n = 33) or placebo (n = 33). There was no difference in ∆EVLWi between the groups (0.19 ml/kg, 95% CI - 3.16 to 2.77, p = 0.89). Imatinib treatment did not affect duration of invasive ventilation (p = 0.29), VFD (p = 0.29) or 28-day mortality (p = 0.79). IV imatinib was well-tolerated and appeared safe. In a subgroup of patients characterized by high IL-6, TNFR1 and SP-D levels (n = 20), imatinib significantly decreased EVLWi per treatment day (- 1.17 ml/kg, 95% CI - 1.87 to - 0.44). CONCLUSIONS: IV imatinib did not reduce pulmonary edema or improve clinical outcomes in invasively ventilated COVID-19 patients. While this trial does not support the use of imatinib in the general COVID-19 ARDS population, imatinib reduced pulmonary edema in a subgroup of patients, underscoring the potential value of predictive enrichment in ARDS trials. Trial registration NCT04794088 , registered 11 March 2021. European Clinical Trials Database (EudraCT number: 2020-005447-23).
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COVID-19 , Edema Pulmonar , Síndrome de Dificultad Respiratoria , Humanos , COVID-19/complicaciones , Mesilato de Imatinib/efectos adversos , Pulmón , Método Doble CiegoRESUMEN
INTRODUCTION: The Radiographic Assessment of Lung Edema (RALE) score provides a semi-quantitative measure of pulmonary edema. In patients with acute respiratory distress syndrome (ARDS), the RALE score is associated with mortality. In mechanically ventilated patients in the intensive care unit (ICU) with respiratory failure not due to ARDS, a variable degree of lung edema is observed as well. We aimed to evaluate the prognostic value of RALE in mechanically ventilated ICU patients. METHODS: Secondary analysis of patients enrolled in the 'Diagnosis of Acute Respiratory Distress Syndrome' (DARTS) project with an available chest X-ray (CXR) at baseline. Where present, additional CXRs at day 1 were analysed. The primary endpoint was 30-day mortality. Outcomes were also stratified for ARDS subgroups (no ARDS, non-COVID-ARDS and COVID-ARDS). RESULTS: 422 patients were included, of which 84 had an additional CXR the following day. Baseline RALE scores were not associated with 30-day mortality in the entire cohort (OR: 1.01, 95% CI: 0.98-1.03, p = 0.66), nor in subgroups of ARDS patients. Early changes in RALE score (baseline to day 1) were only associated with mortality in a subgroup of ARDS patients (OR: 1.21, 95% CI: 1.02-1.51, p = 0.04), after correcting for other known prognostic factors. CONCLUSIONS: The prognostic value of the RALE score cannot be extended to mechanically ventilated ICU patients in general. Only in ARDS patients, early changes in RALE score were associated with mortality.
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Pulmonary edema is a central hallmark of acute respiratory distress syndrome (ARDS). Endothelial dysfunction and epithelial injury contribute to alveolar-capillary permeability but their differential contribution to pulmonary edema development remains understudied. Plasma levels of surfactant protein-D (SP-D), soluble receptor for advanced glycation end products (sRAGE), and angiopoietin-2 (Ang-2) were measured in a prospective, multicenter cohort of invasively ventilated patients. Pulmonary edema was quantified using the radiographic assessment of lung edema (RALE) and global lung ultrasound (LUS) score. Variables were collected within 48 h after intubation. Linear regression was used to examine the association of the biomarkers with pulmonary edema. In 362 patients, higher SP-D, sRAGE, and Ang-2 concentrations were significantly associated with higher RALE and global LUS scores. After stratification by ARDS subgroups (pulmonary, nonpulmonary, COVID, non-COVID), the positive association of SP-D levels with pulmonary edema remained, whereas sRAGE and Ang-2 showed less consistent associations throughout the subgroups. In a multivariable analysis, SP-D levels were most strongly associated with pulmonary edema when combined with sRAGE (RALE score: ßSP-D = 6.79 units/log10 pg/mL, ßsRAGE = 3.84 units/log10 pg/mL, R2 = 0.23; global LUS score: ßSP-D = 3.28 units/log10 pg/mL, ßsRAGE = 2.06 units/log10 pg/mL, R2 = 0.086), whereas Ang-2 did not further improve the model. Biomarkers of epithelial injury and endothelial dysfunction were associated with pulmonary edema in invasively ventilated patients. SP-D and sRAGE showed the strongest association, suggesting that epithelial injury may form a final common pathway in the alveolar-capillary barrier dysfunction underlying pulmonary edema.
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COVID-19 , Edema Pulmonar , Síndrome de Dificultad Respiratoria , Enfermedades Vasculares , Humanos , Edema Pulmonar/etiología , Estudios Prospectivos , Proteína D Asociada a Surfactante Pulmonar , Respiración Artificial/efectos adversos , Ruidos Respiratorios , Biomarcadores/metabolismo , Receptor para Productos Finales de Glicación AvanzadaRESUMEN
BACKGROUND: Comorbidities and socioeconomic issues impact outcome of rotator cuff tear (RCT) repair. There are no data on RCT repair outcome from developing regions. We determined the impact of obesity and smoking following RCT repair in a low-income population. METHODS: This is a retrospective case series. Forty-seven shoulders of 42 patients subjected to open or arthroscopic repair of a RCT with a minimum of 2 years follow-up were cross-sectionally evaluated. Patients were seen in the Orthopaedic Service of the Hospital Geral de Fortaleza-CE, Brazil between March and September 2018. RCT were classified as partial or full-thickness lesions. Fatty infiltration (Goutallier) and tendon retraction (Patte) were recorded as well as obesity (BMI > 30), literacy [>/≤ 8 school years (SY)] and smoking status 6 months prior to surgery (present/absent). Outcomes included pain (visual analogue scale; VAS, 0-10 cm), range of motion [active forward flexion and external rotation (ER)], UCLA and ASES scoring. RESULTS: Patients were 59.9 ± 7.4 years-old, 35(74.4%) female with 19 (17.1-30.2 IQR) median of months from diagnosis to surgery and 25 median months of follow-up (26.9-34.0 IQR); over 90% declared < 900.00 US$ monthly family income and two-thirds had ≤8 SY. Forty patients (85.1%) had full-thickness tears, 7 (14.9%) had Goutallier ≥3 and over 80% had < Patte III stage. Outcomes were similar regardless of fatty infiltration or tendon retraction staging. There were 17 (36.1%) smokers and 13 (27.6%) obese patients. Outcome was similar when comparing obese vs non-obese patients. Smokers had more pain (P = 0.043) and less ER (P = 0.029) with a trend towards worse UCLA and ASES scores as compared to non-smokers though differences did not achieve minimal clinically important difference (MCID) proposed for surgical RCT treatment. After adjusting for obesity, VAS and ER values in smokers were no longer significant (P = 0.2474 and 0.4872, respectively). CONCLUSIONS: Our data document outcomes following RCT repair in a low-income population. Smoking status but not obesity impacted RCT repair outcome though not reaching MCID for surgical treatment.
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Lesiones del Manguito de los Rotadores , Anciano , Artroscopía , Femenino , Humanos , Persona de Mediana Edad , Obesidad/diagnóstico , Obesidad/epidemiología , Pobreza , Lesiones del Manguito de los Rotadores/epidemiología , Lesiones del Manguito de los Rotadores/cirugía , Fumar , Resultado del TratamientoRESUMEN
Congenital amegakaryocytic thrombocytopenia (CAMT) is a severe inherited thrombocytopenia due to loss-of-function mutations affecting the thrombopoietin (TPO) receptor, MPL. Here, we report a new homozygous MPL variant responsible for CAMT in 1 consanguineous family. The propositus and her sister presented with severe thrombocytopenia associated with mild anemia. Next-generation sequencing revealed the presence of a homozygous MPLR464G mutation resulting in a weak cell-surface expression of the receptor in platelets. In cell lines, we observed a defect in MPLR464G maturation associated with its retention in the endoplasmic reticulum. The low cell-surface expression of MPLR464G induced very limited signaling with TPO stimulation, leading to survival and reduced proliferation of cells. Overexpression of a myeloproliferative neoplasm-associated calreticulin (CALR) mutant did not rescue trafficking of MPLR464G to the cell surface and did not induce constitutive signaling. However, it unexpectedly restored a normal response to eltrombopag (ELT), but not to TPO. This effect was only partially mimicked by the purified recombinant CALR mutant protein. Finally, the endogenous CALR mutant was able to restore the megakaryocyte differentiation of patient CD34+ cells carrying MPLR464G in response to ELT.
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Benzoatos/farmacología , Calreticulina , Síndromes Congénitos de Insuficiencia de la Médula Ósea , Hidrazinas/farmacología , Mutación Missense , Pirazoles/farmacología , Receptores de Trombopoyetina , Trombocitopenia , Adulto , Sustitución de Aminoácidos , Calreticulina/genética , Calreticulina/metabolismo , Niño , Preescolar , Síndromes Congénitos de Insuficiencia de la Médula Ósea/tratamiento farmacológico , Síndromes Congénitos de Insuficiencia de la Médula Ósea/genética , Síndromes Congénitos de Insuficiencia de la Médula Ósea/metabolismo , Síndromes Congénitos de Insuficiencia de la Médula Ósea/patología , Femenino , Células HEK293 , Homocigoto , Humanos , Lactante , Masculino , Receptores de Trombopoyetina/genética , Receptores de Trombopoyetina/metabolismo , Trombocitopenia/tratamiento farmacológico , Trombocitopenia/genética , Trombocitopenia/metabolismo , Trombocitopenia/patologíaRESUMEN
BACKGROUND: A weaning trial can be considered a stress test of the cardiorespiratory system; it increases oxygen demand and thus warrants a higher cardiac index and elevated breathing effort. We hypothesized that the combination of easily performed ultrasound measurements of heart, lungs, and diaphragm would yield good diagnostic accuracy to predict extubation failure. METHODS: Adult subjects ventilated for > 72 h with a successful spontaneous breathing trial were included. Ultrasound measurements of heart (left ventricular function), lungs (number of B-lines), and diaphragm thickening fraction were performed during a spontaneous breathing trial. The primary outcomes were sensitivity, specificity, and area under the receiver operating characteristic curve of a holistic ultrasound approach for extubation failure. Re-intubation within 48 h was considered extubation failure. RESULTS: Eighty-three subjects were included, of whom 15 (18%) were re-intubated within 48 h. The sensitivity and specificity of a holistic approach were 100% (78.2-100%) and 7.7% (2.5-17.1%), respectively, with an area under the receiver operating characteristic curve of 0.54. The sensitivity and specificity of diaphragm thickening fraction, using a cutoff value of < 30% for extubation failure were 86.7% (59.5-98.3%) and 25.4% (15.5-37.5%), respectively, with an area under the receiver operating characteristic curve of 0.61. CONCLUSIONS: In subjects ventilated for > 72 h who had a successful spontaneous breathing trial, holistic ultrasound was a weak predictor for extubation failure. (ClinicalTrials.gov registration NCT04196361).
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Extubación Traqueal , Desconexión del Ventilador , Adulto , Diafragma/diagnóstico por imagen , Humanos , Estudios Prospectivos , UltrasonografíaRESUMEN
Scholarship identifies critical consciousness as a key developmental asset in promoting the well-being of adolescents experiencing multiple socio-structural axes of oppression. Girls of color at acute risk for legal system involvement or re-involvement are absent from this literature. They are a critical population in which to examine this construct given their experiences of oppression and the myriad benefits of critical consciousness. The current study addresses this gap by examining traumatic incidents and experiences of racism and sexism as correlates of critical reflection and action among a sample of girls (N = 220; Mean age = 14.5 years; SD = 1.3 years). Using path analysis and multigroup modeling, we examine direct associations between these three manifestations of structural oppression and critical consciousness and explore the interplay of traumatic incidents, and racism and sexism in girls' critical consciousness development. Findings suggest that experiences of sexism and racism, uniquely and positively predict critical action, but not critical reflection. Surprisingly, girls' experiences of traumatic incidents do not predict reflection or action. Finally, multigroup analyses show no evidence that these associations vary by the interplay of traumatic incidents, racism, and sexism. Implications for community psychology values and juvenile legal system practice and policy are discussed.
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Racismo , Adolescente , Estado de Conciencia , Femenino , Humanos , SexismoRESUMEN
The aim of this study was to develop simple sequence repeat (SSR) markers for genetic studies on G. chacoensis, as well as to evaluate their transferability to other bamboo species. Genomic DNA was isolated from G. chacoensis and its partial sequencing was used to find SSR loci. The obtained sequencing data were de novo assembled using the software CLC Genomics Workbench® 8.0v. The SSR loci primers were identified and designed with the software SSRLocator. The selected markers were validated using 56 plants sampled in seven populations from southern Brazil. The markers with potential polymorphism were selected and fluorescently labeled for characterization by capillary electrophoresis. In total, 92 SSR loci were found in G. chacoensis contigs. Suitable primers were designed for 70 SSR loci, and the remaining 22 SSR loci did not have sequences for primer development. Out of 35 selected SSR markers, after PCR optimization, 10 with high polymorphism potential were characterized. These loci can be used in genetic analyses of G. chacoensis and all of them were successfully transferred to other bamboo species. Non-polymorphic loci require further tests with additional plants, from different populations, to identify possibilities of their use.
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Mutations in the MPL gene encoding the human thrombopoietin receptor (TpoR) drive sporadic and familial essential thrombocythemias (ETs). We identified 2 ET patients harboring double mutations in cis in MPL, namely, L498W-H499C and H499Y-S505N. Using biochemical and signaling assays along with partial saturation mutagenesis, we showed that L498W is an activating mutation potentiated by H499C and that H499C and H499Y enhance the activity of the canonical S505N mutation. L498W and H499C can activate a truncated TpoR mutant, which lacks the extracellular domain, indicating these mutations act on the transmembrane (TM) cytosolic domain. Using a protein complementation assay, we showed that L498W and H499C strongly drive dimerization of TpoR. Activation by tryptophan substitution is exquisitely specific for position 498. Using structure-guided mutagenesis, we identified upstream amino acid W491 as a key residue required for activation by L498W or canonical activating mutations such as S505N and W515K, as well as by eltrombopag. Structural data point to a common dimerization and activation path for TpoR via its TM domain that is shared between the small-molecule agonist eltrombopag and canonical and novel activating TpoR mutations that all depend on W491, a potentially accessible extracellular residue that could become a target for therapeutic intervention.
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Benzoatos/farmacología , Predisposición Genética a la Enfermedad , Hidrazinas/farmacología , Mutación , Pirazoles/farmacología , Receptores de Trombopoyetina/agonistas , Receptores de Trombopoyetina/genética , Trombocitemia Esencial/genética , Alelos , Sustitución de Aminoácidos , Línea Celular , Estudios de Asociación Genética , Humanos , Fenotipo , Transducción de Señal/efectos de los fármacos , Trombocitemia Esencial/diagnóstico , Trombocitemia Esencial/metabolismoRESUMEN
The orchid seed banks of Atlantic Forest may be considered a key strategy for the conservation of species threatened with extinction by indiscriminate collection or habitat destruction. The aim of this study was to evaluate the seed viability, to choose the best culture medium for the asymbiotic germination and evaluate germination, after storage for different periods and temperatures for the Brazilian native orchids: Gomesa praetexta (Rchb.f.) M.W.Chase & N.H.Williams, Gomesa forbesii (Hook.) M.W.Chase & N.H.Williams, Gomesa recurva R.Br. and Grandiphyllum divaricatum (Lindl.) Docha Neto. Knudson C (KC), Murashige & Skoog (MS), half-strength MS (1/2 MS macro- and micro-nutrients) and Woody Plant Medium (WPM) culture media were tested for germination. The WPM culture medium was the best for asymbiotic germination of all species evaluated, with high germination percentages and improved seedling development. Seeds of G. divaricatum, G. praetexta, G. recurva and G. forbesii indicated orthodox behavior, with high viability rates after 12 months of storage, being recommended the storage temperature of -80°C for the first three species and -20°C for G. forbesii. The protocol developed in the present study was efficient for seed bank storage, in vitro germination and seedling production of G. divaricatum and G. praetexta, contributing to conservation strategies of these species.
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Técnicas de Cultivo/métodos , Germinación/fisiología , Orchidaceae/crecimiento & desarrollo , Plantones/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Aclimatación , Brasil , Medios de Cultivo , Especies en Peligro de Extinción , Bosques , Orchidaceae/clasificación , Banco de SemillasRESUMEN
Introduction: Classical Myeloproliferative Neoplasms (MPNs) include three disorders: Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF). MPNs are associated with constitutive activation of JAK2 leading to persistent cell signaling downstream of the dimeric myeloid cytokine receptors due to mutations in three genes encoding JAK2, calreticulin (CALR) and the thrombopoietin (TPO) receptor (MPL or TPOR). CALR and MPL mutants induce JAK2 activation that depends on MPL expression, thus explaining why they induce megakaryocyte pathologies including ET and PMF, but not PV. In contrast, JAK2 V617F drives all three diseases as it induces persistent signaling via EPOR, G-CSFR (CSF3R) and MPL. Areas Covered: Here, we review how different pathogenic mutations of MPL are translated into active receptors by inducing stable dimerization. We focus on the unique role of MPL on the hematopoietic stem cell (HSC), explaining why MPL is indispensable for the development of all MPNs. Last but not least, we describe how CALR mutants are pathogenic via binding and activation of MPL. Expert Opinion: Altogether, we believe that MPL is an important, but challenging, therapeutic target in MPNs that requires novel strategies to interrupt the specific conformational changes induced by each mutation or pathologic interaction without compromising the key functions of wild type MPL.
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Trastornos Mieloproliferativos/genética , Receptores de Trombopoyetina/metabolismo , HumanosRESUMEN
The aim of the present report was to demonstrate how a novel approach for immunohistochemical localization of cytokinins in the leaf and particularly in the phloem may complement to the study of their long-distance transport. Different procedures of fixation were used to conjugate either cytokinin bases or their ribosides to proteins of cytoplasm to enable visualization and differential localization of these cytokinins in the leaf cells of wheat plants. In parallel to immunolocalization of cytokinins in the leaf cells, we immunoassayed distribution of free bases of cytokinins, their nucleotides and ribosides between roots and shoots of wheat plants as well as their presence in phloem sap after incubation of leaves in a solution supplemented with either trans-zeatin or isopentenyladenine. The obtained data show ribosylation of the zeatin applied to the leaves and its elevated level in the phloem sap supported by in vivo localization showing the presence of ribosylated forms of zeatin in leaf vessels. This suggests that conversion of zeatin to its riboside is important for the shoot-to-root transport of zeatin-type cytokinins in wheat. Exogenous isopentenyladenine was not modified, but diffused from the leaves as free base. These metabolic differences may not be universal and may depend on the plant species and age. Although the measurements of cytokinins in the phloem sap and root tissue is the most defining for determining cytokinin transport, study of immunolocalization of either free cytokinin bases or their ribosylated forms may be a valuable source of information for predicting their transport in the phloem and to the roots.
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Citocininas/metabolismo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Triticum/metabolismo , Transporte Biológico , Isopenteniladenosina/metabolismo , Floema/metabolismo , Zeatina/metabolismoRESUMEN
A well-functioning hematopoietic system requires a certain robustness and flexibility to maintain appropriate quantities of functional mature blood cells, such as red blood cells and platelets. This review focuses on the cytokine receptor that plays a significant role in thrombopoiesis: the receptor for thrombopoietin (TPO-R; also known as MPL). Here, we survey the work to date to understand how this receptor functions at a molecular level throughout its lifecycle, from traffic to the cell surface, dimerization and binding cognate cytokine via its extracellular domain, through to its subsequent activation of associated Janus kinases and initiation of downstream signaling pathways, as well as the regulation of these processes. Atomic level resolution structures of TPO-R have remained elusive. The identification of disease-causing mutations in the receptor has, however, offered some insight into structure and function relationships, as has artificial means of receptor activation, through TPO mimetics, transmembrane-targeting receptor agonists, and engineering in dimerization domains. More recently, a novel activation mechanism was identified whereby mutated forms of calreticulin form complexes with TPO-R via its extracellular N-glycosylated domain. Such complexes traffic pathologically in the cell and persistently activate JAK2, downstream signal transducers and activators of transcription (STATs), and other pathways. This pathologic TPO-R activation is associated with a large fraction of human myeloproliferative neoplasms.