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1.
Chemistry ; : e202401265, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38863386

RESUMO

The present work reports synthesis, characterization and theoretical insights on novel hydroxymethyl-bishomocubanone derivatives. Twelve new bishomocubanes (BHCs) were synthesized and fully characterized by various spectroscopic techniques and single crystal X-ray analysis. The densities of the title compounds were found in the range of 1.34-1.59 g/cm3. Density-functional theory (DFT) based calculations at B3LYP/6-311++G(d,p) level of theory were performed on  ten selected BHC based cage compounds. Propulsive and ballistic properties of newly synthesized hydroxymethyl-bishomocubanone derivatives in solid and liquid propulsion systems were calculated, and the results suggested that these compounds are superior to conventional fuel RP1 and binder HTPB. The detonation parameters revealed that these compounds are not explosive in nature and safe to use as solid propellants. Furthermore, kinetic and thermal stabilities of the title compounds were determined by HOMO-LUMO energy gap, ESP maps, impact sensitivity (h50) and bond dissociation energies (BDEs) followed by thermogravimetric analysis (TGA) and differential thermogravimetry analysis (DTA). Three compounds, a dinitroazide (Isp,vac= 310.98s), a dinitrate (Isp,vac = 309.51s), and a dinitronitrate (Isp,vac= 309.20s) were found to be excellent candidates for volume limited applications.

2.
Nat Commun ; 15(1): 1821, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418901

RESUMO

Interferon gamma (IFNγ) is a critical cytokine known for its diverse roles in immune regulation, inflammation, and tumor surveillance. However, while IFNγ levels were elevated in sera of most newly diagnosed acute myeloid leukemia (AML) patients, its complex interplay in AML remains insufficiently understood. We aim to characterize these complex interactions through comprehensive bulk and single-cell approaches in bone marrow of newly diagnosed AML patients. We identify monocytic AML as having a unique microenvironment characterized by IFNγ producing T and NK cells, high IFNγ signaling, and immunosuppressive features. IFNγ signaling score strongly correlates with venetoclax resistance in primary AML patient cells. Additionally, IFNγ treatment of primary AML patient cells increased venetoclax resistance. Lastly, a parsimonious 47-gene IFNγ score demonstrates robust prognostic value. In summary, our findings suggest that inhibiting IFNγ is a potential treatment strategy to overcoming venetoclax resistance and immune evasion in AML patients.


Assuntos
Interferon gama , Leucemia Mieloide Aguda , Sulfonamidas , Humanos , Interferon gama/farmacologia , Prognóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Microambiente Tumoral
3.
Cancer Res Commun ; 4(3): 671-681, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38391202

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous malignancy of the blood primarily treated with intensive chemotherapy. The allogeneic T-cell antileukemic activity via donor lymphocyte infusions and stem cell transplantation suggests a potential role for checkpoint blockade therapy in AML. While clinical trials employing these treatments have fallen short of expected results, a deeper exploration into the functional states of T cells in AML could bridge this knowledge gap. In this study, we analyzed the polyfunctional activity of T cells in a cohort of patients with relapsed/refractory (RelRef) AML treated on the clinical trial (ClinicalTrials.gov identifier: NCT02397720) of combination therapy using azacitidine and nivolumab (Aza/Nivo). We utilized the single-cell polyfunctional multiplexed immune assay IsoPlexis to evaluate the CD4 and CD8 T cells in peripheral blood and bone marrow samples collected before and after immunotherapy. This revealed at a pseudobulk level that the CD4 T cells exhibited higher functional activity post-immunotherapy (post-IO), suggesting that CD4-directed therapies may play a role in RelRef AML. Additional single-cell analysis revealed significant differences in baseline polyfunctionality in bone marrows of responders as compared with nonresponders for both CD4 and CD8 T cells. Overall, this study highlights the impact of polyfunctional assessment in understanding CD4 and CD8 dynamics in contexts of therapy in AML. SIGNIFICANCE: We found T-cell polyfunctionality differs between local and systemic microenvironments. Enhanced variability in proteomic profiles of bone marrow CD4 T cells post-IO suggests their pivotal role in AML treatment response. Single-cell analysis identified novel CD4 and CD8 T-cell functional groups linked to immunotherapy response within the bone marrow.


Assuntos
Inibidores de Checkpoint Imunológico , Leucemia Mieloide Aguda , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Proteômica , Secretoma , Leucemia Mieloide Aguda/tratamento farmacológico , Linfócitos T CD8-Positivos , Microambiente Tumoral
4.
Cancer Immunol Res ; : OF1-OF18, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37285177

RESUMO

Comprehensive investigation of CD8+ T cells in acute myeloid leukemia (AML) is essential for developing immunotherapeutic strategies beyond immune checkpoint blockade. Herein, we performed single-cell RNA profiling of CD8+ T cells from 3 healthy bone marrow donors and 23 newly diagnosed (NewlyDx) and 8 relapsed/refractory (RelRef) patients with AML. Cells coexpressing canonical exhaustion markers formed a cluster constituting <1% of all CD8+ T cells. We identified two effector CD8+ T-cell subsets characterized by distinct cytokine and metabolic profiles that were differentially enriched in NewlyDx and RelRef patients. We refined a 25-gene CD8-derived signature correlating with therapy resistance, including genes associated with activation, chemoresistance, and terminal differentiation. Pseudotemporal trajectory analysis supported enrichment of a terminally differentiated state in CD8+ T cells with high CD8-derived signature expression at relapse or refractory disease. Higher expression of the 25-gene CD8 AML signature correlated with poorer outcomes in previously untreated patients with AML, suggesting that the bona fide state of CD8+ T cells and their degree of differentiation are clinically relevant. Immune clonotype tracking revealed more phenotypic transitions in CD8 clonotypes in NewlyDx than in RelRef patients. Furthermore, CD8+ T cells from RelRef patients had a higher degree of clonal hyperexpansion associated with terminal differentiation and higher CD8-derived signature expression. Clonotype-derived antigen prediction revealed that most previously unreported clonotypes were patient-specific, suggesting significant heterogeneity in AML immunogenicity. Thus, immunologic reconstitution in AML is likely to be most successful at earlier disease stages when CD8+ T cells are less differentiated and have greater capacity for clonotype transitions.

5.
Cancer Immunol Res ; 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37163233

RESUMO

Comprehensive investigation of CD8+ T cells in acute myeloid leukemia (AML) is essential for developing immunotherapeutic strategies beyond immune checkpoint blockade. Herein, we performed single-cell RNA profiling of CD8+ T cells from 3 healthy bone marrow donors and 23 newly diagnosed (NewlyDx) and 8 relapsed/refractory (RelRef) AML patients. Cells co-expressing canonical exhaustion markers formed a cluster constituting <1% of all CD8+ T cells. We identified two effector CD8+ T cell subsets characterized by distinct cytokine and metabolic profiles that were differentially enriched in NewlyDx and RelRef patients. We refined a 25-gene CD8-derived signature correlating with therapy resistance, including genes associated with activation, chemoresistance, and terminal differentiation. Pseudotemporal trajectory analysis supported enrichment of a terminally differentiated state in CD8+ T cells with high CD8-derived signature expression at relapse or refractory disease. Higher expression of the 25-gene CD8 AML signature correlated with poorer outcomes in previously untreated AML patients, suggesting that the bona fide state of CD8+ T cells and their degree of differentiation are clinically relevant. Immune clonotype tracking revealed more phenotypic transitions in CD8 clonotypes in NewlyDx than in RelRef patients. Furthermore, CD8+ T cells from RelRef patients had a higher degree of clonal hyperexpansion associated with terminal differentiation and higher CD8-derived signature expression. Clonotype-derived antigen prediction revealed that most previously unreported clonotypes were patient-specific, suggesting significant heterogeneity in AML immunogenicity. Thus, immunologic reconstitution in AML is likely to be most successful at earlier disease stages when CD8+ T cells are less differentiated and have greater capacity for clonotype transitions.

6.
Ultrasound ; 25(4): 245-247, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29163661

RESUMO

Foreign body impaction at the cricopharyngeal level can be a life-threatening emergency. While traditionally, removal of these is performed in the operating room setting, patients with relatively unstable airways or significant discomfort may require immediate extraction to prevent further injury. This is the case of an 85-year-old man who presented to the emergency department in significant discomfort following aspiration of a large partial denture. We report here the first known use of ultrasound in an emergent airway situation to rapidly localize and retrieve an aspirated foreign body.

7.
Emerg Med Pract ; 18(3): 1-20, 24; quiz 20-1, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26881977

RESUMO

Pelvic trauma accounts for only 3% of all skeletal injuries but may have mortality as high as 45% in cases of severe trauma. Significant high-grade-mechanism trauma to the pelvis must always take the abdomen into consideration for evaluation. The focused assessment with sonography for trauma (FAST) examination has been shown to be a valuable tool in assessing the unstable trauma patient with blunt abdominal injury, though its diagnostic utility is much less well-defined than in primary pelvic trauma. This systematic review explores the utility and limitations of the FAST examination in patients with blunt pelvic trauma and discusses the timing for the examination during the trauma survey. Newer techniques for emergency department management of the unstable trauma patient are also addressed.


Assuntos
Traumatismos Abdominais/diagnóstico por imagem , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/lesões , Pelve/diagnóstico por imagem , Pelve/lesões , Traumatismos Abdominais/terapia , Adulto , Idoso , Procedimentos Clínicos , Diagnóstico Diferencial , Serviço Hospitalar de Emergência , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/terapia , Humanos , Masculino , Pelve/anatomia & histologia , Ultrassonografia , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/terapia , Adulto Jovem
8.
J Ultrasound ; 18(4): 415-20, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26550078

RESUMO

Acute limb ischemia (ALI) is a limb-threatening and life-threatening disease process. Mural aortic thrombosis (MAT) is a rare cause of ALI. While there is limited evidence on the use of bedside ultrasound for the detection of ALI or MAT, duplex ultrasound remains the standard in the diagnosis and ultimate medical decision-making in patients with acute and chronic limb ischemia. Point-of-care ultrasound may be used in the evaluation of patients with signs and symptoms of this disease entity. This is a case of a 79-year-old female with a complicated medical history, who presented with a pulseless right leg and abdominal tenderness. The patient quickly decompensated requiring intubation for airway protection. A post-intubation arterial blood gas (ABG) was unsuccessfully attempted in the right femoral artery, prompting an ultrasound-guided ABG. On B-mode ultrasound evaluation, echogenic material was visualized in the right common femoral artery without evidence of Doppler flow signal. Additionally, a partially obstructing echogenic material was also noted at the femoro-saphenous vein junction with only partial compressibility by compression sonography. A computed tomography angiography of the aorta was performed indicating extensive infrarenal aortic thrombosis. The patient expired despite the relatively prompt diagnosis, highlighting the importance of early identification of acute arterial occlusion.

9.
Cell Signal ; 27(7): 1413-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25862520

RESUMO

The type II epithelial-mesenchymal transition (EMT) produces airway fibrosis and remodeling, contributing to the severity of asthma and chronic obstructive pulmonary disease. While numerous studies have been done on the mechanisms of the transition itself, few studies have investigated the system effects of EMT on signaling networks. Here, we use mixed effects modeling to develop a computational model of phospho-protein signaling data that compares human small airway epithelial cells (hSAECs) with their EMT-transformed counterparts across a series of perturbations with 8 ligands and 5 inhibitors, revealing previously uncharacterized changes in signaling in the EMT state. Strong couplings between menadione, TNFα and TGFß and their known phospho-substrates were revealed after mixed effects modeling. Interestingly, the overall phospho-protein response was attenuated in EMT, with loss of Mena and TNFα coupling to heat shock protein (HSP)-27. These differences persisted after correction for EMT-induced changes in phospho-protein substrate abundance. Construction of network topology maps showed significant changes between the two cellular states, including a linkage between glycogen synthase kinase (GSK)-3α and small body size/mothers against decapentaplegic (SMAD)2. The model also predicted a loss of p38 mitogen activated protein kinase (p38MAPK)-independent HSP27 signaling, which we experimentally validated. We further characterized the relationship between HSP27 and signal transducers and activators of transcription (STAT)3 signaling, and determined that loss of HSP27 following EMT is only partially responsible for the downregulation of STAT3. These rewired connections represent therapeutic targets that could potentially reverse EMT and restore a normal phenotype to the respiratory mucosa.


Assuntos
Transição Epitelial-Mesenquimal , Modelos Moleculares , Transdução de Sinais , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Humanos , Microscopia Imunoeletrônica , Fosforilação , Fator de Transcrição STAT3/metabolismo , Fator de Crescimento Transformador alfa/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
J Cardiothorac Vasc Anesth ; 22(1): 34-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18249328

RESUMO

OBJECTIVES: Because hetastarches have deleterious effects on coagulation that increase with molecular weight (MWt), risk of coagulopathy associated with a high MWt hemoglobin-based oxygen carrier (HBOC) was studied. DESIGN: Preliminary laboratory study of donor blood using thromboelastography (TEG). SETTING: University laboratory. PARTICIPANTS: Volunteer donor blood. INTERVENTIONS: Experiments simulated hemodilution during clinical resuscitation of hemorrhagic shock with varying doses of HBOCs. Coagulopathy related to 1:11, 1:5, 1:2, or 1:1 dilution of whole blood with normal saline, 6% hetastarch (670 kilodaltons [kD]), hemoglobin glutamer-200 (HBOC-200, 200 kD), or OxyVita (OXYVITA Inc, New Windsor, NY) (a new-generation, zero-link polymerized bovine hemoglobin-based oxygen carrier, 33 megadaltons) were analyzed. MEASUREMENTS AND MAIN RESULTS: At 2 lower levels of hemodilution, hetastarch, HBOC-200, and OxyVita produced equivalent reductions in maximum clot strength (TEG-MA and TEG-G) that reached statistical significance compared with whole blood and normal saline. At 2 higher dilutions, OxyVita and HBOC-200 impaired maximum clot strength compared with whole blood, normal saline, and hetastarch. Dilution with hetastarch had a greater effect on clot propagation (K and alpha) than either HBOC. CONCLUSIONS: OxyVita and HBOC-200, HBOCs with different MWt, had similar effects on coagulation as measured by TEG. The impairment of coagulation by HBOCs and hetastarch occurred at doses corresponding to 12 mL/kg or a blood volume replacement of 17%. The use of HBOCs at doses corresponding to 23 mL/kg or a blood volume replacement of 33% significantly decreased coagulation to levels associated with increased clinical bleeding in this preliminary study. Minimal coagulopathic effects are expected with use of OxyVita at the manufacturer's anticipated effective dose of 10 g or 2 to 3 mL/kg.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Substitutos Sanguíneos/farmacologia , Hemoglobinas/farmacologia , Tromboelastografia/efeitos dos fármacos , Substitutos Sanguíneos/administração & dosagem , Relação Dose-Resposta a Droga , Hemoglobinas/administração & dosagem , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/farmacologia , Choque Hemorrágico/sangue , Choque Hemorrágico/terapia , Cloreto de Sódio/farmacologia
12.
Anesth Analg ; 100(2): 437-439, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15673872

RESUMO

In this study, we validated the accuracy of lactate measurements (YSI 2700 SELECT glucose/lactate analyzer) in the presence of methemoglobin from an oxidized bag of hemoglobin-based oxygen carrier (Met-HBOC), hemoglobin glutamer-200 (Oxyglobin; Biopure Corp). Different combinations of concentrated L-lactate solution, pooled canine plasma, and Plasmalyte A were added to 4 sample groups (1%, 10%, 20%, and 40% Met-HBOC [1.3 g/dL]) to yield linear increases in lactate concentration in consecutive samples. The mean difference between measured and calculated lactate was -5.1 mg/dL (1% Met-HBOC), -5.8 mg/dL (10% Met-HBOC), -4.6 mg (20% Met-HBOC), and -8.5 mg/dL (40% Met-HBOC). The root mean square error was 6.5 mg/dL, 7.4 mg/dL, 6.8 mg/dL, and 10.3 mg/dL, respectively. The Bland-Altman correlation (r) was r = -0.94 (P = 0.01), r = -0.91 (P < 0.001), r = -0.90 (P < 0.001), and r = -0.94 (P < 0.001), respectively, where r = 0 for perfect agreement between measured and calculated values. Results indicate that true lactate levels in the presence of Met-HBOC are underestimated when measured by an YSI 2700 analyzer independent of the amount of Met-HBOC present. When interpreting lactate concentrations from a patient with a HBOC present in plasma, underestimation of true lactate levels may occur unrelated to methemoglobin concentrations.


Assuntos
Substitutos Sanguíneos/química , Ácido Láctico/sangue , Metemoglobina/química , Animais , Cães , Hemoglobinas , Peróxido de Hidrogênio/química , Oxidantes/química , Oximetria
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