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1.
Clin Exp Dermatol ; 47(8): 1617-1621, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35661395

RESUMO

A woman who had undergone haematopoietic stem cell transplantation presented with cutaneous features suggestive of graft-versus-host disease. Histopathological examination revealed a diffuse dermal infiltration of atypical monomorphic cells with a high proliferative index. Immunohistochemistry revealed positivity for monocytic markers, but negativity for T-cell markers.


Assuntos
Exantema , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Prurigo , Feminino , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Prurido
2.
Vet Pathol ; 59(5): 873-882, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35400234

RESUMO

Plasmodium falciparum remains one of the world's deadliest diseases and with ongoing concerns of evolving drug resistance, there is a need for continued refinement of the Plasmodium coatneyi infection model in macaques to study severe malaria. As such, the systemic ultrastructural lesions associated with P. coatneyi infection in splenectomized rhesus macaques was evaluated in 6 animals. Autopsy samples from multiple areas of the central nervous system (CNS), kidneys, heart, liver, and lungs of all 6 animals were processed for electron microscopy. A systematic analysis of the ultrastructural changes associated with the plasmodium was undertaken by multiple pathologists to ensure consensus. All tissues exhibited marked sequestration of infected red blood cells comprised either of cytoadherence to endothelium or rosette formation, associated with variable degrees of host cell damage in a range of tissues that in severe cases resulted in necrosis. This is the first complete systemic evaluation of ultrastructural tissue lesions in P. coatneyi-infected rhesus macaques, and the findings have important implications evaluating of the use of this model for the study of severe malaria caused by P. falciparum in humans.


Assuntos
Malária , Plasmodium , Animais , Eritrócitos/patologia , Eritrócitos/ultraestrutura , Humanos , Macaca mulatta , Malária/complicações , Malária/veterinária , Microscopia Eletrônica/veterinária
3.
Artigo em Inglês | MEDLINE | ID: mdl-31818818

RESUMO

Artemether-lumefantrine antimalarial efficacy in pregnancy could be compromised by reduced drug exposure. Population-based simulations suggested that therapeutic efficacy would be improved if the treatment duration was increased. We assessed the efficacy, tolerability, and pharmacokinetics of an extended 5-day regimen of artemether-lumefantrine compared to the standard 3-day treatment in 48 pregnant women and 48 nonpregnant women with uncomplicated falciparum malaria in an open-label, randomized clinical trial. Babies were assessed at birth and 1, 3, 6, and 12 months. Nonlinear mixed-effects modeling was used to characterize the plasma concentration-time profiles of artemether and lumefantrine and their metabolites. Both regimens were highly efficacious (100% PCR-corrected cure rates) and well tolerated. Babies followed up to 1 year had normal development. Parasite clearance half-lives were longer in pregnant women (median [range], 3.30 h [1.39 to 7.83 h]) than in nonpregnant women (2.43 h [1.05 to 6.00 h]) (P=0.005). Pregnant women had lower exposures to artemether and dihydroartemisinin than nonpregnant women, resulting in 1.2% decreased exposure for each additional week of gestational age. By term, these exposures were reduced by 48% compared to nonpregnant patients. The overall exposure to lumefantrine was improved with the extended regimen, with no significant differences in exposures to lumefantrine or desbutyl-lumefantrine between pregnant and nonpregnant women. The extended artemether-lumefantrine regimen was well tolerated and safe and increased the overall antimalarial drug exposure and so could be a promising treatment option in pregnancy in areas with lower rates of malaria transmission and/or emerging drug resistance. (This study has been registered at ClinicalTrials.gov under identifier NCT01916954.).


Assuntos
Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Adulto , África , Artemeter/uso terapêutico , Artemisininas/uso terapêutico , Feminino , Humanos , Gravidez , Adulto Jovem
4.
Clin Infect Dis ; 67(7): 991-999, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-29538635

RESUMO

Background: Acute kidney injury independently predicts mortality in falciparum malaria. It is unknown whether acetaminophen's capacity to inhibit plasma hemoglobin-mediated oxidation is renoprotective in severe malaria. Methods: This phase 2, open-label, randomized controlled trial conducted at two hospitals in Bangladesh assessed effects on renal function, safety, pharmacokinetic (PK) properties and pharmacodynamic (PD) effects of acetaminophen. Febrile patients (>12 years) with severe falciparum malaria were randomly assigned to receive acetaminophen (1 g 6-hourly for 72 hours) or no acetaminophen, in addition to intravenous artesunate. Primary outcome was the proportional change in creatinine after 72 hours stratified by median plasma hemoglobin. Results: Between 2012 and 2014, 62 patients were randomly assigned to receive acetaminophen (n = 31) or no acetaminophen (n = 31). Median (interquartile range) reduction in creatinine after 72 hours was 23% (37% to 18%) in patients assigned to acetaminophen, versus 14% (29% to 0%) in patients assigned to no acetaminophen (P = .043). This difference in reduction was 37% (48% to 22%) versus 14% (30% to -71%) in patients with hemoglobin ≥45000 ng/mL (P = .010). The proportion with progressing kidney injury was higher among controls (subdistribution hazard ratio, 3.0; 95% confidence interval, 1.1 to 8.5; P = .034). PK-PD analyses showed that higher exposure to acetaminophen increased the probability of creatinine improvement. No patient fulfilled Hy's law for hepatotoxicity. Conclusions: In this proof-of-principle study, acetaminophen showed renoprotection without evidence of safety concerns in patients with severe falciparum malaria, particularly in those with prominent intravascular hemolysis. Clinical Trials Registration: NCT01641289.


Assuntos
Acetaminofen/uso terapêutico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Artesunato/efeitos adversos , Artesunato/uso terapêutico , Malária Falciparum/tratamento farmacológico , Acetaminofen/administração & dosagem , Acetaminofen/farmacocinética , Adolescente , Adulto , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/farmacocinética , Analgésicos não Narcóticos/uso terapêutico , Antimaláricos/efeitos adversos , Antimaláricos/uso terapêutico , Área Sob a Curva , Feminino , Humanos , Masculino , Adulto Jovem
5.
Curr Opin Infect Dis ; 31(1): 69-77, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29206655

RESUMO

PURPOSE OF REVIEW: Cerebral impairment and acute kidney injury (AKI) are independent predictors of mortality in both adults and children with severe falciparum malaria. In this review, we present recent advances in understanding the pathophysiology, clinical features, and management of these complications of severe malaria, and discuss future areas of research. RECENT FINDINGS: Cerebral malaria and AKI are serious and well recognized complications of severe malaria. Common pathophysiological pathways include impaired microcirculation, due to sequestration of parasitized erythrocytes, systemic inflammatory responses, and endothelial activation. Recent MRI studies show significant brain swelling in both adults and children with evidence of posterior reversible encephalopathy syndrome-like syndrome although targeted interventions including mannitol and dexamethasone are not beneficial. Recent work shows association of cell-free hemoglobin oxidation stress involved in the pathophysiology of AKI in both adults and children. Paracetamol protected renal function likely by inhibiting cell-free-mediated oxidative stress. It is unclear if heme-mediated endothelial activation or oxidative stress is involved in cerebral malaria. SUMMARY: The direct causes of cerebral and kidney dysfunction remain incompletely understood. Optimal treatment involves prompt diagnosis and effective antimalarial treatment with artesunate. Renal replacement therapy reduces mortality in AKI but delayed diagnosis is an issue.


Assuntos
Injúria Renal Aguda/fisiopatologia , Injúria Renal Aguda/terapia , Coma/fisiopatologia , Coma/terapia , Malária Falciparum/complicações , Acetaminofen/administração & dosagem , Injúria Renal Aguda/patologia , Animais , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Coma/patologia , Dexametasona/administração & dosagem , Modelos Animais de Doenças , Humanos , Rim/patologia , Manitol/administração & dosagem , Estresse Oxidativo , Resultado do Tratamento
6.
BMC Infect Dis ; 17(1): 313, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-28449641

RESUMO

BACKGROUND: Intravascular hemolysis is an intrinsic feature of severe malaria pathophysiology but the pathogenic role of cell-free hemoglobin-mediated oxidative stress in severe malaria associated acute kidney injury (AKI) is unknown. METHODS: As part of a prospective observational study, enrolment plasma cell-free hemoglobin (CFH), lipid peroxidation markers (F2-isoprostanes (F2-IsoPs) and isofurans (IsoFs)), red cell deformability, and serum creatinine were quantified in Bangladeshi patients with severe falciparum malaria (n = 107), uncomplicated malaria (n = 80) and sepsis (n = 28). The relationships between these indices and kidney function and clinical outcomes were examined. RESULTS: AKI was diagnosed at enrolment in 58% (62/107) of consecutive patients with severe malaria, defined by an increase in creatinine ≥1.5 times expected baseline. Severe malaria patients with AKI had significantly higher plasma cell-free hemoglobin (geometric mean CFH: 8.8 µM; 95% CI, 6.2-12.3 µM), F2-isoprostane (56.7 pg/ml; 95% CI, 45.3-71.0 pg/ml) and isofuran (109.2 pg/ml; 95% CI, 85.1-140.1 pg/ml) concentrations on enrolment compared to those without AKI (CFH: 5.1 µM; 95% CI, 4.0-6.6 µM; P = 0.018; F2-IsoPs: 27.8 pg/ml; 95% CI, 23.7-32.7 pg/ml; P < 0.001; IsoFs: 41.7 pg/ml; 95% CI, 30.2-57.6 pg/ml; P < 0.001). Cell-free hemoglobin correlated with markers of hemolysis, parasite burden (P. falciparum histidine rich protein 2 (PfHRP2)), and F2-IsoPs. Plasma F2-IsoPs and IsoFs inversely correlated with pH, positively correlated with creatinine, PfHRP2 and fractional excretion of sodium, and were higher in patients later requiring hemodialysis. Plasma F2-IsoP concentrations also inversely correlated with red cell deformability and were higher in fatal cases. Mixed effects modeling including an interaction term for CFH and time showed that F2-IsoPs, IsoFs, PfHRP2, CFH, and red cell rigidity were independently associated with increasing creatinine over 72 h. Multivariable logistic regression showed that admission F2-IsoPs, IsoFs and red cell deformability were associated with the need for subsequent hemodialysis. CONCLUSIONS: Cell-free hemoglobin and lipid peroxidation are associated with acute kidney injury and disease severity in falciparum malaria, suggesting a pathophysiological role in renal tubular injury. Evaluation of adjunctive therapies targeting cell-free hemoglobin-mediated oxidative stress is warranted.


Assuntos
Injúria Renal Aguda/etiologia , Hemoglobinas/metabolismo , Malária Falciparum/metabolismo , Estresse Oxidativo , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Adulto , Antígenos de Protozoários/sangue , Biomarcadores/sangue , Creatinina/sangue , Eritrócitos/patologia , F2-Isoprostanos/sangue , F2-Isoprostanos/urina , Feminino , Humanos , Peroxidação de Lipídeos , Malária Falciparum/complicações , Malária Falciparum/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas de Protozoários/sangue , Diálise Renal , Sepse/sangue , Sepse/etiologia
8.
Malar J ; 14: 389, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26437894

RESUMO

BACKGROUND: The pathogenesis of pulmonary oedema (PE) in patients with severe malaria is still unclear. It has been hypothesized that lung injury depends, in addition to microvascular obstruction, on an increased pulmonary capillary pressure and altered alveolar-capillary membrane permeability, causing pulmonary fluid accumulation. METHODS: This study compared the histopathological features of lung injury in Southeast Asian patients (n = 43) who died from severe Plasmodium falciparum malaria, and correlated these with clinical history in groups with or without PE. To investigate the expression of mediators that may influence fluid accumulation in PE, immunohistochemistry and image analysis were performed on controls and sub-sets of patient with or without PE. RESULTS: The expression of leukocyte sub-set antigens, bronchial interleukin (IL)-33, γ-epithelium sodium channel (ENaC), aquaporin (AQP)-1 and -5, and control cytokeratin staining was quantified in the lung tissue of severe malaria patients. Bronchial IL-33 expression was significantly increased in severe malaria patients with PE. Malaria patients with shock showed significantly increased bronchial IL-33 compare to other clinical manifestations. Bronchial IL-33 levels were positively correlated with CD68+ monocyte and elastase + neutrophil, septal congestion and hyaline membrane formation. Moreover, the expression of both vascular smooth muscle cell (VSMC) and bronchial γ-ENaC significantly decreased in severe malaria patients with PE. Both VSMC and bronchial γ-ENaC were negatively correlated with the degree of parasitized erythrocyte sequestration, alveolar thickness, alveolar expansion score, septal congestion score, and malarial pigment score. In contrast AQP-1 and -5 and pan cytokeratin levels were similar between groups. CONCLUSIONS: The results suggest that IL-33 may play a role in lung injury during severe malaria and lead to PE. Both VSMC and bronchial γ-ENaC downregulation may explain pulmonary fluid disturbances and participate in PE pathogenesis in severe malaria patients.


Assuntos
Canais Epiteliais de Sódio/metabolismo , Interleucina-33/metabolismo , Malária Falciparum/complicações , Malária Falciparum/patologia , Edema Pulmonar/etiologia , Edema Pulmonar/patologia , Adolescente , Adulto , Sudeste Asiático , Criança , Pré-Escolar , Feminino , Histocitoquímica , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Malar J ; 14: 246, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26081927

RESUMO

BACKGROUND: Severe falciparum malaria may be complicated by haemolysis after parasite clearance, however the mechanisms remain unclear. Recent reports describe a pattern of delayed onset haemolysis among non-immune travellers with hyperparasitaemia treated with intravenous artesunate, termed post-artesunate delayed haemolysis (PADH). The occurrence and clinical impact of PADH following severe malaria infections in areas of unstable transmission are unknown. CASE: A 45-year-old Bangladeshi male was initially admitted to a local hospital with severe falciparum malaria complicated by hyperparasitaemia and treated with intravenous artesunate. Twenty days from his first presentation he was readmitted with delayed onset haemolytic anaemia and acute kidney injury. Multiple blood transfusions and haemodialysis were required. Renal biopsy revealed acute tubular injury and haem pigment nephropathy. His haemoglobin and renal function recovered to baseline after 62 days from his second admission. DISCUSSION: This case highlights the differential diagnosis of post-malaria delayed onset haemolysis, including the recently described syndrome of post-artemisinin delayed haemolysis. The pathophysiology contributing to acute kidney injury in this patient and the limited treatment options are discussed. CONCLUSIONS: This report describes PADH complicated by acute kidney injury in an adult patient living in a malaria hypoendemic region who subsequently required blood transfusions and haemodialysis. This case emphasizes the importance of routine follow up of haemoglobin and renal function in artesunate-treated patients who have recovered from severe malaria.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Anemia Hemolítica/tratamento farmacológico , Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Parasitemia/tratamento farmacológico , Injúria Renal Aguda/parasitologia , Administração Intravenosa , Anemia Hemolítica/parasitologia , Artesunato , Bangladesh , Humanos , Malária Falciparum/complicações , Masculino , Pessoa de Meia-Idade , Parasitemia/complicações , Resultado do Tratamento
10.
Malar J ; 13: 91, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24618154

RESUMO

BACKGROUND: Acute kidney injury (AKI) complicating severe Plasmodium falciparum malaria occurs in up to 40% of adult patients. The case fatality rate reaches 75% in the absence of renal replacement therapy (RRT). The precise pathophysiology of AKI in falciparum malaria remains unclear. Histopathology shows acute tubular necrosis with localization of host monocytes and parasitized red blood cells in the microvasculature. This study explored the relationship of plasma soluble urokinase-type plasminogen activator receptor (suPAR), as a proxy-measure of mononuclear cell activation, and plasma P. falciparum histidine rich protein 2 (PfHRP2), as a measure of sequestered parasite burden, with AKI in severe malaria. METHODS: Admission plasma suPAR and PfHRP2 concentrations were assessed in Bangladeshi adults with severe falciparum malaria (n=137). Patients were stratified according to AKI severity based on admission creatinine clearance. RESULTS: A total of 106 (77%) patients had AKI; 32 (23%), 42 (31%) and 32 (23%) were classified into 'mild, 'moderate' and 'severe' AKI groups, respectively. Plasma suPAR and PfHRP2 concentrations increased with AKI severity (test-for-trend P <0.0001) and correlated with other markers of renal dysfunction. Admission plasma suPAR and PfHRP2 concentrations were higher in patients who later required RRT (P <0.0001 and P=0.0004, respectively). In a multivariate analysis, both increasing suPAR and PfHRP2 were independently associated with increasing urine neutrophil gelatinase-associated lipocalin concentration, a marker of acute tubular necrosis (ß=16.54 (95% CI 6.36-26.71) and ß=0.07 (0.02-0.11), respectively). CONCLUSIONS: Both sequestered parasite burden and immune activation contribute to the pathogenesis of AKI in severe falciparum malaria.


Assuntos
Injúria Renal Aguda/patologia , Antígenos de Protozoários/sangue , Biomarcadores/sangue , Malária Falciparum/complicações , Malária Falciparum/imunologia , Proteínas de Protozoários/sangue , Receptores de Ativador de Plasminogênio Tipo Uroquinase/sangue , Injúria Renal Aguda/imunologia , Adolescente , Adulto , Animais , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Malária Falciparum/patologia , Masculino , Pessoa de Meia-Idade , Carga Parasitária , Adulto Jovem
11.
J Infect Dis ; 208(2): 192-8, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23585685

RESUMO

One hundred and twenty years ago, the Italian malariologists Marchiafava and Bignami proposed that the fundamental pathological process underlying lethal falciparum malaria was microvascular obstruction. Since then, several alternative hypotheses have been proposed. These formed the basis for adjunctive interventions, which have either been ineffective or harmful. Recent evidence strongly suggests that Marchiafava and Bignami were right.


Assuntos
Malária/patologia , Microvasos/patologia , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Humanos , Malária/sangue , Malária/tratamento farmacológico , Malária/parasitologia , Microvasos/efeitos dos fármacos , Plasmodium falciparum/fisiologia
12.
Malar J ; 12: 50, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23383853

RESUMO

BACKGROUND: Plasma angiopoietin (Ang)-2 is associated with disease severity and mortality in adults and children with falciparum malaria. However the mechanism of action of the angiopoietins in fatal malaria is unclear. This study aimed to determine whether the expression of Ang-1 and Ang-2 and their receptor Tie-2 in cerebral endothelial or parenchymal cells was specific to cerebral malaria (CM), correlated with coma or other severe clinical features, and whether plasma and CSF levels of these markers correlated with the clinical and neuropathological features of severe and fatal malaria in Vietnamese adults. METHODS: Immunohistochemistry was performed for Ang-1, Ang-2 and Tie-2 on post-mortem brain tissue from fatal malaria cases and controls. Quantitative ELISA for plasma and cerebrospinal fluid levels of Ang-1, Ang-2 and Tie-2 was done to compare fatal cases with surviving patients from the same study. RESULTS: Immunohistochemistry revealed significant differences in expression in endothelial and parenchymal cells compared to controls. However there was no significant difference in expression of these markers on endothelial cells, astroglial cells or neurons between CM and non-cerebral malaria cases. Immunostaining of Ang-1, Ang-2 and Tie-2 was also not associated with Plasmodium falciparum-infected erythrocyte sequestration in the brain. However Ang-1 and Ang-2 expression in neurons was significantly correlated with the incidence of microscopic haemorrhages. Plasma levels of Ang-2 and Ang-2/Ang-1 ratio were associated with the number of severe malaria complications and were significant and independent predictors of metabolic acidosis and fatal outcome. CONCLUSIONS: The independent prognostic significance of Ang-2 and the Ang-2/Ang-1 ratio in severe malaria was confirmed, although immunohistochemistry in fatal cases did not reveal increased expression on brain endothelium in cerebral versus non-cerebral cases. Activation of the Ang-Tie-2 pathway in severe malaria is therefore related to acidosis, number of severity criteria and outcome, but is not a specific event in the brain during cerebral malaria.


Assuntos
Encéfalo/patologia , Perfilação da Expressão Gênica , Malária Falciparum/patologia , Receptor TIE-2/análise , Ribonuclease Pancreático/análise , Proteínas de Transporte Vesicular/análise , Adulto , Biomarcadores/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Coma/patologia , Células Endoteliais/fisiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Masculino , Prognóstico , Receptor TIE-2/sangue , Receptor TIE-2/líquido cefalorraquidiano , Estudos Retrospectivos , Ribonuclease Pancreático/sangue , Ribonuclease Pancreático/líquido cefalorraquidiano , Proteínas de Transporte Vesicular/sangue , Proteínas de Transporte Vesicular/líquido cefalorraquidiano
13.
J Infect Dis ; 205(4): 663-71, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22207648

RESUMO

The pathogenesis of coma in severe Plasmodium falciparum malaria remains poorly understood. Obstruction of the brain microvasculature because of sequestration of parasitized red blood cells (pRBCs) represents one mechanism that could contribute to coma in cerebral malaria. Quantitative postmortem microscopy of brain sections from Vietnamese adults dying of malaria confirmed that sequestration in the cerebral microvasculature was significantly higher in patients with cerebral malaria (CM; n = 21) than in patients with non-CM (n = 23). Sequestration of pRBCs and CM was also significantly associated with increased microvascular congestion by infected and uninfected erythrocytes. Clinicopathological correlation showed that sequestration and congestion were significantly associated with deeper levels of premortem coma and shorter time to death. Microvascular congestion and sequestration were highly correlated as microscopic findings but were independent predictors of a clinical diagnosis of CM. Increased microvascular congestion accompanies coma in CM, associated with parasite sequestration in the cerebral microvasculature.


Assuntos
Coma/patologia , Eritrócitos/parasitologia , Hiperemia/patologia , Malária Cerebral/patologia , Malária Falciparum/patologia , Microvasos/patologia , Plasmodium falciparum/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Encéfalo/patologia , Feminino , Histocitoquímica , Humanos , Malária Cerebral/complicações , Malária Falciparum/complicações , Masculino , Microscopia , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Análise de Sobrevida , Vietnã
14.
Leukemia ; 37(2): 348-358, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36470992

RESUMO

The grading of fibrosis in myeloproliferative neoplasms (MPN) is an important component of disease classification, prognostication and monitoring. However, current fibrosis grading systems are only semi-quantitative and fail to fully capture sample heterogeneity. To improve the quantitation of reticulin fibrosis, we developed a machine learning approach using bone marrow trephine (BMT) samples (n = 107) from patients diagnosed with MPN or a reactive marrow. The resulting Continuous Indexing of Fibrosis (CIF) enhances the detection and monitoring of fibrosis within BMTs, and aids MPN subtyping. When combined with megakaryocyte feature analysis, CIF discriminates between the frequently challenging differential diagnosis of essential thrombocythemia (ET) and pre-fibrotic myelofibrosis with high predictive accuracy [area under the curve = 0.94]. CIF also shows promise in the identification of MPN patients at risk of disease progression; analysis of samples from 35 patients diagnosed with ET and enrolled in the Primary Thrombocythemia-1 trial identified features predictive of post-ET myelofibrosis (area under the curve = 0.77). In addition to these clinical applications, automated analysis of fibrosis has clear potential to further refine disease classification boundaries and inform future studies of the micro-environmental factors driving disease initiation and progression in MPN and other stem cell disorders.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Mielofibrose Primária , Trombocitemia Essencial , Humanos , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/patologia , Policitemia Vera/patologia , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/patologia , Medula Óssea/patologia , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/patologia , Fibrose
15.
Nat Commun ; 14(1): 7216, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940670

RESUMO

Single cell spatial interrogation of the immune-structural interactions in COVID -19 lungs is challenging, mainly because of the marked cellular infiltrate and architecturally distorted microstructure. To address this, we develop a suite of mathematical tools to search for statistically significant co-locations amongst immune and structural cells identified using 37-plex imaging mass cytometry. This unbiased method reveals a cellular map interleaved with an inflammatory network of immature neutrophils, cytotoxic CD8 T cells, megakaryocytes and monocytes co-located with regenerating alveolar progenitors and endothelium. Of note, a highly active cluster of immature neutrophils and CD8 T cells, is found spatially linked with alveolar progenitor cells, and temporally with the diffuse alveolar damage stage. These findings offer further insights into how immune cells interact in the lungs of severe COVID-19 disease. We provide our pipeline [Spatial Omics Oxford Pipeline (SpOOx)] and visual-analytical tool, Multi-Dimensional Viewer (MDV) software, as a resource for spatial analysis.


Assuntos
COVID-19 , Neutrófilos , Humanos , Linfócitos T CD8-Positivos , Pulmão , Linfócitos T Citotóxicos
16.
Carcinogenesis ; 33(9): 1717-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22777959

RESUMO

Hypoxia-inducible factors, HIF-1α and HIF-2α, are expressed in the majority of clear-cell renal cell carcinoma (CC-RCC). In vitro, HIFα isoforms regulate a differential set of genes, and their effects in vivo within CC-RCC tumours may affect outcome. The role of angiogenesis and HIFα transcriptional products, including those involved in cell metabolism and morphological dedifferentiation have not been extensively investigated and might have relevance to the development of antiangiogenic or anti-HIFα trials in primary CC-RCC, either before or after radical nephrectomy. We analysed 168 consecutive clear-cell renal tumours from 1983 to 1999 within tissue microarrays and assessed expression of HIF-1α and HIF-2α together with the protein expression of seven of their target genes (BNIP3, CA9, Cyclin D1, GLUT-1, LDH5, Oct-4 and VEGF). The expression of these factors was compared with patient overall survival and CD31 angiogenesis. We found that HIFα antigenicity deteriorated with the age of the paraffin block (P < 0.0001) and in tumours from 1983 to 1992 was deemed not to be reliable. Similar findings were found in aged archival osteosarcoma samples. This might have important implications for retrospective biomarker studies that rely on archival tissue material. HIF-1α(HIGH)/HIF-2α(LOW) tumours had a worse overall survival compared with HIF-1α(LOW)/HIF-2α(LOW) tumours (P = 0.04). Surprisingly, on multivariate analysis, high levels of CD31(+) angiogenesis was shown to be an independent prognostic marker of increased overall survival (P = 0.003). We propose that better differentiation of vascular endothelium may be a reflection of a greater production of vessel stabilization factors versus pro-angiogenic factors, and therefore a less aggressive phenotype.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Carcinoma de Células Renais/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Neoplasias Renais/tratamento farmacológico , Molécula-1 de Adesão Celular Endotelial a Plaquetas/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/análise , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Ciclina D1/análise , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Prognóstico
17.
Clin Infect Dis ; 54 Suppl 2: S165-71, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22403232

RESUMO

The diagnosis of etiology in severe pneumonia remains a challenging area. Postmortem lung tissue potentially increases the sensitivity of investigations for identification of causative pathogens in fatal cases of pneumonia and can confirm antemortem microbiological diagnoses. Tissue sampling allows assessment of histological patterns of disease and ancillary immunohistochemical or molecular diagnostic techniques. It may also enhance the recognition of noninfectious conditions that clinically simulate acute pneumonia. Biobanking of lung tissue or postmortem culture isolates offers opportunities for new pathogen discovery and research into host-pathogen interactions. The Pneumonia Etiology Research for Child Health study proposes a percutaneous needle biopsy approach to obtain postmortem samples, rather than a full open autopsy. This has the advantage of greater acceptability to relatives, but risks greater sampling error. Both approaches may be susceptible to microbiological contamination or pathogen degradation. However, previous autopsy studies have confirmed the value of histological examination in revealing unsuspected pathogens and influencing clinical guidelines for the diagnosis and treatment of future pneumonia cases.


Assuntos
Autopsia/métodos , Pneumonia/etiologia , Autopsia/ética , Autopsia/normas , Viés , Biópsia por Agulha/métodos , Criança , Humanos , Imuno-Histoquímica , Pneumopatias/diagnóstico , Pneumopatias/microbiologia , Pneumopatias/patologia , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Pneumonia/diagnóstico , Pneumonia/epidemiologia , Sensibilidade e Especificidade , Manejo de Espécimes/métodos
18.
BJU Int ; 107(9): 1488-99, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20840329

RESUMO

OBJECTIVE: • To compare immunostaining protocols using different antibodies for the type 1 insulin-like growth factor receptor (IGF-1R) in channel transurethal resection of the prostate (chTURP) chips, and to investigate how IGF-1R expression varies with time in serial prostate cancer specimens from individual patients. METHODS: • We studied IGF-1R expression in 44 prostate cancer specimens from 18 patients who had undergone serial chTURP at least 3 months apart. • Retrospective analysis of the hospital notes was undertaken to obtain clinical information, including age, Gleason score, prostate-specific antigen (PSA) level, hormone treatment and metastatic disease status at the time of each operation. • After an optimization process using three commercially-available IGF-1R antibodies, we used two antibodies for semiquantititve immunostaining of serial chTURP chips. RESULTS: • Santa Cruz antibody sc713 gave positive staining in IGF-1R null R- cells, and was not used further. Antibodies from Cell Signaling Technology (Beverly, MA, USA) (CS) and NeoMarkers Inc. (Fremont, CA, USA) (NM) did not stain R- cells and, in prostate tissue, showed staining of the glandular epithelium, with negligible stromal staining. All 44 chTURP samples contained identifiable malignant tissue and, of these, 73% and 64% scored moderately or strongly (score 3 or 4) with the CS and NM antibodies respectively. • There was significant correlation of IGF-1R scores of malignant tissue between the two antibodies (P < 0.001). By contrast, staining of benign glands showed poor correlation between antibodies: CS gave significantly weaker staining than malignant epithelium in the same sections (P < 0.001), whereas NM showed poor discrimination between malignant and benign glands. IGF-1R staining scores generated by the CS antibody were used to analyze the clinical data. • Most patients (six of seven) with falling IGF-1R staining scores were responding to androgen deprivation therapy (confirmed by PSA response) between operations. Conversely, in seven of eight patients who had progression to androgen-independence between procedures, IGF-1R levels increased or remained high. Finally, seven of 11 patients who developed radiologically confirmed metastases between procedures showed stable or increasing IGF-1R staining scores. CONCLUSION: • The present study is the first to assess changes in IGF-1R expression in serial prostate cancer samples. The results obtained indicate that IGF-1R expression usually remains high throughout the course of histologically-proven disease progression in serial specimens, suggesting that the IGF-1R remains a valid treatment target for advanced prostate cancer.


Assuntos
Neoplasias da Próstata/metabolismo , Receptor IGF Tipo 1/metabolismo , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/uso terapêutico , Progressão da Doença , Humanos , Immunoblotting , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/metabolismo , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Estudos Retrospectivos , Regulação para Cima
19.
BJU Int ; 107(8): 1290-6, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21929519

RESUMO

UNLABELLED: Study Type--Therapy (case series) Level of Evidence What's known on the subject? and What does the study add? Renal cancer is increasingly diagnosed when tumours are small and asymptomatic, during routine abdominal imaging. Whilst surgery is an effective and potentially curative option, it carries a significant risk of complications. Recent work suggests that thermally ablative therapies (RFA, cryotherapy, HIFU) may be suitable minimally invasive treatment options in selected patients. The success of extracorporeal HIFU has been limited by the abdominal wall and rib-cage limiting energy delivery. For this study, a purpose-built laparoscopic HIFU probe was designed to allow direct application of the transducer to the tumour surface, thus facilitating tumour destruction. Successful and accurate tumour destruction was demonstrated, paving the way for further clinical trials, subject to device modifications. OBJECTIVE: • To test and establish clinical proof of concept for a laparoscopic high-intensity focused ultrasound (HIFU) device that facilitates delivery of ultrasound by direct application of a probe to the tumour surface. PATIENTS AND METHODS: • Twelve patients with renal tumours were treated with laparoscopic HIFU using a newly designed probe inserted via an 18-mm laparoscopic port. • HIFU treatment was targeted at a pre-defined proportion of the tumour and immediate laparoscopic partial or radical nephrectomy was then performed. RESULTS: • No tumour ablation was seen in the first five patients which made modifications in the treatment protocol necessary. After this, definite histological evidence of ablation was seen in the remaining seven patients. • The ablated zones were within the targeted area in all patients and no intra-lesional skipping was seen. • Subcapsular skipping was seen at the probe-tumour interface in two patients with viable tumour cells seen at microscopy. • One patient did not undergo surgical extirpation; subsequent biopsy revealed no viable tumour cells. • There were no intraoperative or postoperative complications directly related to HIFU therapy and patients have reached a mean (range) follow-up of 15 (8-24) months with no evidence of metastatic disease or late complications. CONCLUSIONS: • Tumour ablation with laparoscopic HIFU is feasible. • Homogenous ablation can be achieved with no vital tissue within the targeted zone. • The technique is associated with low morbidity and may have a role in the definitive management of small tumours.


Assuntos
Carcinoma de Células Renais/terapia , Neoplasias Renais/terapia , Laparoscopia , Terapia por Ultrassom/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Nefrectomia/métodos , Resultado do Tratamento , Ultrassonografia
20.
Malar J ; 10: 267, 2011 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-21923924

RESUMO

BACKGROUND: The role of brain oedema in the pathophysiology of cerebral malaria is controversial. Coma associated with severe Plasmodium falciparum malaria is multifactorial, but associated with histological evidence of parasitized erythrocyte sequestration and resultant microvascular congestion in cerebral vessels. To determine whether these changes cause breakdown of the blood-brain barrier and resultant perivascular or parenchymal cerebral oedema, histology, immunohistochemistry and image analysis were used to define the prevalence of histological patterns of oedema and the expression of specific molecular pathways involved in water balance in the brain in adults with fatal falciparum malaria. METHODS: The brains of 20 adult Vietnamese patients who died of severe malaria were examined for evidence of disrupted vascular integrity. Immunohistochemistry and image analysis was performed on brainstem sections for activation of the vascular endothelial growth factor (VEGF) receptor 2 and expression of the aquaporin 4 (AQP4) water channel protein. Fibrinogen immunostaining was assessed as evidence of blood-brain barrier leakage and perivascular oedema formation. Correlations were performed with clinical, biochemical and neuropathological parameters of severe malaria infection. RESULTS: The presence of oedema, plasma protein leakage and evidence of VEGF signalling were heterogeneous in fatal falciparum malaria and did not correlate with pre-mortem coma. Differences in vascular integrity were observed between brain regions with the greatest prevalence of disruption in the brainstem, compared to the cortex or midbrain. There was a statistically non-significant trend towards higher AQP4 staining in the brainstem of cases that presented with coma (P = .02). CONCLUSIONS: Histological evidence of cerebral oedema or immunohistochemical evidence of localised loss of vascular integrity did not correlate with the occurrence of pre-mortem coma in adults with fatal falciparum malaria. Enhanced expression of AQP4 water channels in the brainstem may, therefore, reflect a mix of both neuropathological or attempted neuroprotective responses to oedema formation.


Assuntos
Coma/etiologia , Coma/fisiopatologia , Malária Cerebral/complicações , Plasmodium falciparum/patogenicidade , Adulto , Idoso , Aquaporina 4/análise , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Edema Encefálico/patologia , Edema Encefálico/fisiopatologia , Feminino , Fibrinogênio/análise , Histocitoquímica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neuroimagem , Fator A de Crescimento do Endotélio Vascular/análise , Adulto Jovem
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