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1.
Cell ; 187(12): 3120-3140.e29, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38714197

RESUMO

Non-hematopoietic cells are essential contributors to hematopoiesis. However, heterogeneity and spatial organization of these cells in human bone marrow remain largely uncharacterized. We used single-cell RNA sequencing (scRNA-seq) to profile 29,325 non-hematopoietic cells and discovered nine transcriptionally distinct subtypes. We simultaneously profiled 53,417 hematopoietic cells and predicted their interactions with non-hematopoietic subsets. We employed co-detection by indexing (CODEX) to spatially profile over 1.2 million cells. We integrated scRNA-seq and CODEX data to link predicted cellular signaling with spatial proximity. Our analysis revealed a hyperoxygenated arterio-endosteal neighborhood for early myelopoiesis, and an adipocytic localization for early hematopoietic stem and progenitor cells (HSPCs). We used our CODEX atlas to annotate new images and uncovered mesenchymal stromal cell (MSC) expansion and spatial neighborhoods co-enriched for leukemic blasts and MSCs in acute myeloid leukemia (AML) patient samples. This spatially resolved, multiomic atlas of human bone marrow provides a reference for investigation of cellular interactions that drive hematopoiesis.


Assuntos
Medula Óssea , Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Proteômica , Análise de Célula Única , Transcriptoma , Humanos , Análise de Célula Única/métodos , Medula Óssea/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Proteômica/métodos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Hematopoese , Nicho de Células-Tronco , Células da Medula Óssea/metabolismo , Células da Medula Óssea/citologia
2.
PLoS Pathog ; 19(6): e1011468, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37384799

RESUMO

Controlled human malaria infections (CHMI) are a valuable tool to study parasite gene expression in vivo under defined conditions. In previous studies, virulence gene expression was analyzed in samples from volunteers infected with the Plasmodium falciparum (Pf) NF54 isolate, which is of African origin. Here, we provide an in-depth investigation of parasite virulence gene expression in malaria-naïve European volunteers undergoing CHMI with the genetically distinct Pf 7G8 clone, originating in Brazil. Differential expression of var genes, encoding major virulence factors of Pf, PfEMP1s, was assessed in ex vivo parasite samples as well as in parasites from the in vitro cell bank culture that was used to generate the sporozoites (SPZ) for CHMI (Sanaria PfSPZ Challenge (7G8)). We report broad activation of mainly B-type subtelomeric located var genes at the onset of a 7G8 blood stage infection in naïve volunteers, mirroring the NF54 expression study and suggesting that the expression of virulence-associated genes is generally reset during transmission from the mosquito to the human host. However, in 7G8 parasites, we additionally detected a continuously expressed single C-type variant, Pf7G8_040025600, that was most highly expressed in both pre-mosquito cell bank and volunteer samples, suggesting that 7G8, unlike NF54, maintains expression of some previously expressed var variants during transmission. This suggests that in a new host, the parasite may preferentially express the variants that previously allowed successful infection and transmission. Trial registration: ClinicalTrials.gov - NCT02704533; 2018-004523-36.


Assuntos
Culicidae , Malária Falciparum , Malária , Parasitos , Animais , Humanos , Culicidae/genética , Expressão Gênica , Malária Falciparum/genética , Malária Falciparum/parasitologia , Parasitos/genética , Plasmodium falciparum/genética , Esporozoítos , Virulência/genética
3.
Tumour Biol ; 46(s1): S283-S295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37270828

RESUMO

Circulating tumor DNA (ctDNA), i.e., DNA shed from tumor cells into the bloodstream, is emerging as one of the most useful plasma biomarkers in patients with multiple types of cancer, including patients with non-small cell lung cancer (NSCLC). Indeed, NSCLC was the first malignancy in which measurement of ctDNA was approved for clinical use, i.e., mutational testing of EGFR for predicting response to EGFR tyrosine kinase inhibitors in patients with advanced disease. Although historically the gold standard method for EGFR mutational analysis required tumor tissue, the use of ctDNA is more convenient and safer for patients, results in a faster turn-around-time for return of results, provides a more complete representation of genetic alteration in heterogeneous tumors and is less costly to perform. Emerging uses of ctDNA in patients with lung or suspected lung cancer include screening for early disease, surveillance following initial treatment and monitoring response to therapy in metastatic disease. For evaluating therapy response, ctDNA appears to be especially useful in patients receiving targeted therapies against driver oncogenes or immunotherapy. Further work should not only validate these emerging findings but also aim to optimize and standardize ctDNA assays.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , DNA Tumoral Circulante/genética , Receptores ErbB/genética , Mutação , Biomarcadores Tumorais/genética
4.
PLoS Genet ; 17(2): e1009269, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33630855

RESUMO

Malaria remains a major public health problem in many countries. Unlike influenza and HIV, where diversity in immunodominant surface antigens is understood geographically to inform disease surveillance, relatively little is known about the global population structure of PfEMP1, the major variant surface antigen of the malaria parasite Plasmodium falciparum. The complexity of the var multigene family that encodes PfEMP1 and that diversifies by recombination, has so far precluded its use in malaria surveillance. Recent studies have demonstrated that cost-effective deep sequencing of the region of var genes encoding the PfEMP1 DBLα domain and subsequent classification of within host sequences at 96% identity to define unique DBLα types, can reveal structure and strain dynamics within countries. However, to date there has not been a comprehensive comparison of these DBLα types between countries. By leveraging a bioinformatic approach (jumping hidden Markov model) designed specifically for the analysis of recombination within var genes and applying it to a dataset of DBLα types from 10 countries, we are able to describe population structure of DBLα types at the global scale. The sensitivity of the approach allows for the comparison of the global dataset to ape samples of Plasmodium Laverania species. Our analyses show that the evolution of the parasite population emerging out of Africa underlies current patterns of DBLα type diversity. Most importantly, we can distinguish geographic population structure within Africa between Gabon and Ghana in West Africa and Uganda in East Africa. Our evolutionary findings have translational implications in the context of globalization. Firstly, DBLα type diversity can provide a simple diagnostic framework for geographic surveillance of the rapidly evolving transmission dynamics of P. falciparum. It can also inform efforts to understand the presence or absence of global, regional and local population immunity to major surface antigen variants. Additionally, we identify a number of highly conserved DBLα types that are present globally that may be of biological significance and warrant further characterization.


Assuntos
Antígenos de Protozoários/genética , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Variação Antigênica , Evolução Molecular , Gabão , Gana , Humanos , Malária Falciparum/epidemiologia , Cadeias de Markov , Modelos Estatísticos , Domínios Proteicos , Proteínas de Protozoários/metabolismo , Uganda
5.
BMC Biol ; 21(1): 65, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013531

RESUMO

BACKGROUND: The protozoan malaria parasite Plasmodium falciparum has a complex life cycle during which it needs to differentiate into multiple morphologically distinct life forms. A key process for transmission of the disease is the development of male and female gametocytes in the human blood, yet the mechanisms determining sexual dimorphism in these haploid, genetically identical sexual precursor cells remain largely unknown. To understand the epigenetic program underlying the differentiation of male and female gametocytes, we separated the two sexual forms by flow cytometry and performed RNAseq as well as comprehensive ChIPseq profiling of several histone variants and modifications. RESULTS: We show that in female gametocytes the chromatin landscape is globally remodelled with respect to genome-wide patterns and combinatorial usage of histone variants and histone modifications. We identified sex specific differences in heterochromatin distribution, implicating exported proteins and ncRNAs in sex determination. Specifically in female gametocytes, the histone variants H2A.Z/H2B.Z were highly enriched in H3K9me3-associated heterochromatin. H3K27ac occupancy correlated with stage-specific gene expression, but in contrast to asexual parasites this was unlinked to H3K4me3 co-occupancy at promoters in female gametocytes. CONCLUSIONS: Collectively, we defined novel combinatorial chromatin states differentially organising the genome in gametocytes and asexual parasites and unravelled fundamental, sex-specific differences in the epigenetic code. Our chromatin maps represent an important resource for future understanding of the mechanisms driving sexual differentiation in P. falciparum.


Assuntos
Malária Falciparum , Parasitos , Animais , Masculino , Feminino , Humanos , Plasmodium falciparum , Histonas/genética , Heterocromatina/genética , Heterocromatina/metabolismo , Montagem e Desmontagem da Cromatina , Diferenciação Sexual/genética , Malária Falciparum/parasitologia , Cromatina/genética , Cromatina/metabolismo , Parasitos/genética , Parasitos/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
6.
J Infect Dis ; 228(8): 1099-1107, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37341543

RESUMO

BACKGROUND: Antibodies to variant surface antigens (VSAs) such as Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) may vary with malaria severity. The influence of ABO blood group on antibody development is not understood. METHODS: Immunoglobulin G antibodies to VSAs in Papua New Guinean children with severe (n = 41) or uncomplicated (n = 30) malaria were measured by flow cytometry using homologous P falciparum isolates. Isolates were incubated with ABO-matched homologous and heterologous acute and convalescent plasma. RNA was used to assess var gene transcription. RESULTS: Antibodies to homologous, but not heterologous, isolates were boosted in convalescence. The relationship between antibody and severity varied by blood group. Antibodies to VSAs were similar in severe and uncomplicated malaria at presentation, higher in severe than uncomplicated malaria in convalescence, and higher in children with blood group O than other children. Six var gene transcripts best distinguished severe from uncomplicated malaria, including UpsA and 2 CIDRα1 domains. CONCLUSIONS: ABO blood group may influence antibody acquisition to VSAs and susceptibility to severe malaria. Children in Papua New Guinea showed little evidence of acquisition of cross-reactive antibodies following malaria. Var gene transcripts in Papua New Guinean children with severe malaria were similar to those reported from Africa.


Assuntos
Malária Falciparum , Malária , Humanos , Criança , Plasmodium falciparum/genética , Sistema ABO de Grupos Sanguíneos/genética , Convalescença , Antígenos de Protozoários/genética , Proteínas de Protozoários/genética , Antígenos de Superfície , Transcrição Gênica , Anticorpos Antiprotozoários
7.
Semin Cancer Biol ; 79: 58-67, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-32741700

RESUMO

Dysfunction of the TP53 (p53) gene occurs in most if not all human malignancies. Two principal mechanisms are responsible for this dysfunction; mutation and downregulation of wild-type p53 mediated by MDM2/MDM4. Because of its almost universal inactivation in malignancy, p53 is a highly attractive target for the development of new anticancer drugs. Although multiple strategies have been investigated for targeting dysfunctional p53 for cancer treatment, only 2 of these have so far yielded compounds for testing in clinical trials. These strategies include the identification of compounds for reactivating the mutant form of p53 back to its wild-type form and compounds for inhibiting the interaction between wild-type p53 and MDM2/MDM4. Currently, multiple p53-MDM2/MDM4 antagonists are undergoing clinical trials, the most advanced being idasanutlin which is currently undergoing testing in a phase III clinical trial in patients with relapsed or refractory acute myeloid leukemia. Two mutant p53-reactivating compounds have progressed to clinical trials, i.e., APR-246 and COTI-2. Although promising data has emerged from the testing of both MDM2/MDM4 inhibitors and mutant p53 reactivating compounds in preclinical models, it is still unclear if these agents have clinical efficacy. However, should any of the compounds currently being evaluated in clinical trials be shown to have efficacy, it is likely to usher in a new era in cancer treatment, especially as p53 dysfunction is so prevalent in human cancers.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Ciclo Celular/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Aminoquinolinas/uso terapêutico , Proteínas de Ciclo Celular/metabolismo , Humanos , Neoplasias/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirrolidinas/uso terapêutico , Quinuclidinas/uso terapêutico , Tiossemicarbazonas/uso terapêutico , Proteína Supressora de Tumor p53/genética , para-Aminobenzoatos/uso terapêutico
8.
Crit Rev Clin Lab Sci ; : 1-13, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936529

RESUMO

Circulating tumor DNA (ctDNA, DNA shed by cancer cells) is emerging as one of the most transformative cancer biomarkers discovered to-date. Although potentially useful at all the phases of cancer detection and patient management, one of its most exciting possibilities is as a relatively noninvasive pan-cancer screening test. Preliminary findings with ctDNA tests such as Galleri or CancerSEEK suggest that they have high specificity (> 99.0%) for malignancy. Their sensitivity varies depending on the type of cancer and stage of disease but it is generally low in patients with stage I disease. A major advantage of ctDNA over existing screening strategies is the potential ability to detect multiple cancer types in a single test. A limitation of most studies published to-date is that they are predominantly case-control investigations that were carried out in patients with a previous diagnosis of malignancy and that used apparently healthy subjects as controls. Consequently, the reported sensitivities, specificities and positive predictive values might be lower if the tests are used for screening in asymptomatic populations, that is, in the population where these tests are likely be employed. To demonstrate clinical utility in an asymptomatic population, these tests must be shown to reduce cancer mortality without causing excessive overdiagnosis in a large randomized prospective randomized trial. Such trials are currently ongoing for Galleri and CancerSEEK.

9.
Bioinformatics ; 38(7): 1823-1829, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35025988

RESUMO

MOTIVATION: Recombination is a fundamental process in molecular evolution, and the identification of recombinant sequences is thus of major interest. However, current methods for detecting recombinants are primarily designed for aligned sequences. Thus, they struggle with analyses of highly diverse genes, such as the var genes of the malaria parasite Plasmodium falciparum, which are known to diversify primarily through recombination. RESULTS: We introduce an algorithm to detect recent recombinant sequences from a dataset without a full multiple alignment. Our algorithm can handle thousands of gene-length sequences without the need for a reference panel. We demonstrate the accuracy of our algorithm through extensive numerical simulations; in particular, it maintains its effectiveness in the presence of insertions and deletions. We apply our algorithm to a dataset of 17 335 DBLα types in var genes from Ghana, observing that sequences belonging to the same ups group or domain subclass recombine amongst themselves more frequently, and that non-recombinant DBLα types are more conserved than recombinant ones. AVAILABILITY AND IMPLEMENTATION: Source code is freely available at https://github.com/qianfeng2/detREC_program. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Variação Genética , Proteínas de Protozoários , Proteínas de Protozoários/genética , Plasmodium falciparum/genética , Software , Evolução Molecular
10.
Invest New Drugs ; 41(4): 541-550, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37233863

RESUMO

TP53 (p53) and MYC are amongst the most frequently altered genes in cancer. Both are thus attractive targets for new anticancer therapies. Historically, however, both genes have proved challenging to target and currently there is no approved therapy against either. The aim of this study was to investigate the effect of the mutant p53 reactivating drug, COTI-2 on MYC. Total MYC, pSer62 MYC and pThr58 MYC were detected using Western blotting. Proteasome-mediated degradation was determined using the proteasome, inhibitor MG-132, while MYC half-life was measured using pulse chase experiments in the presence of cycloheximide. Cell proliferation was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Treatment of 5 mutant p53 breast cancer cell lines with COTI-2 resulted in dose-dependent MYC degradation. Addition of the proteasome inhibitor, MG132, rescued the degradation, suggesting that this proteolytic system was at least partly responsible for the inactivation of MYC. Using cycloheximide in pulse chase experiments, COTI-2 was found to reduce the half-life of MYC in 2 different mutant p53 breast cancer cell lines, i.e., from 34.8 to 18.6 min in MDA-MB-232 cells and from 29.6 to 20.3 min in MDA-MB-468 cells. Co-treatment with COTI-2 and the MYC inhibitor, MYCi975 resulted in synergistic growth inhibition in all 4 mutant p53 cell lines investigated. The dual ability of COTI-2 to reactivate mutant p53 and degrade MYC should enable this compound to have broad application as an anticancer drug.


Assuntos
Antineoplásicos , Neoplasias da Mama , Feminino , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células , Cicloeximida/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/farmacologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
11.
Cells Tissues Organs ; 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37231815

RESUMO

The primary cilium is a solitary, sensory organelle with many roles in bone development, maintenance, and function. In the osteogenic cell lineage, including skeletal stem cells, osteoblasts and osteocytes, the primary cilium plays a vital role in the regulation of bone formation and this has made it a promising pharmaceutical target to maintain bone health. While the role of the primary cilium in the osteogenic cell lineage has been increasingly characterized, little is known about the potential impact of targeting the cilium in relation to osteoclasts, a hematopoietic cell responsible for bone resorption. The objective of this study was to determine whether osteoclasts have a primary cilium and to investigate whether or not the primary cilium of macrophages, osteoclast precursors, serves a functional role in osteoclast formation. Using immunocytochemistry, we showed the macrophages have a primary cilium while osteoclasts lack this organelle. Furthermore, we increased macrophage primary cilia incidence and length using fenoldopam mesylate and found that cells undergoing such treatment showed a significant decrease in the expression of osteoclast markers tartrate-resistant acid phosphatase, cathepsin K, and c-Fos as well as decreased osteoclast formation. This work is the first to show that macrophage primary cilia resorption may be a necessary step for osteoclast differentiation. Since primary cilia and pre-osteoclasts are responsive to fluid flow, we applied fluid flow at magnitudes present in the bone marrow to differentiating cells and found that osteoclastic gene expression by macrophages was not affected by fluid-flow mechanical stimulation, suggesting that the role of the primary cilium in osteoclastogenesis is not a mechanosensory one. The primary cilium has been suggested to play a role in bone formation, and our findings indicate that it may also present a means to regulate bone resorption, presenting a dual benefit of developing ciliary-targeted pharmaceuticals for bone disease.

12.
Nutr Cancer ; 75(2): 450-460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36495143

RESUMO

Although best known for its role in skeletal health, a deficiency of vitamin D has also been implicated in cancer formation and progression. The aim of this article was to review the relationship between circulating levels of vitamin D {25(OH)D} and both the risk of developing cancer and outcome from cancer. We also reviewed the effects of vitamin D supplementation on cancer risk and outcome. Our primary focus was on patients with colorectal and breast cancer, as these are two of the cancer types best investigated with respect to the effects of vitamin D on cancer risk and outcome. Based on our review of the literature, we conclude that although low circulating levels of 25(OH)D appears to be associated with an increased risk of developing breast and colorectal cancer, the available evidence suggests that supplementation of healthy subjects with vitamin D does not decrease cancer risk. Supplementation may however, improve outcomes in patients who develop cancer, but this finding remains to be confirmed in an appropriately powered randomized clinical trial.


Assuntos
Neoplasias da Mama , Deficiência de Vitamina D , Humanos , Feminino , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico , Suplementos Nutricionais , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
BMC Cardiovasc Disord ; 23(1): 519, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880616

RESUMO

BACKGROUND: To compare functional and health related quality of life outcomes post-transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) in patients with critical aortic stenosis (AS) across low to high-risk surgical candidates. These patient-centred factors will be compared between both groups in the short to medium term time frames and will aid in shared decision making between patients and healthcare workers. MATERIALS AND METHODS: We conducted a systematic review and meta-analysis of randomised controlled trials which compared TAVI with SAVR and reported on quality of life (QoL) and functional scores. The scores used were the Kansas City Cardiomyopathy Questionnaire (KCCQ), Euroqol-5DL (EQ5DL), the short form-36/12 (SF-36/12) and the NYHA. RESULTS: We identified eight trials with a total of 8898 participants. Both groups showed improvements from baseline at one month. At one month there was a statistically significant difference in standardised mean difference (SMD) in favour of TAVI for EQ5DL (SMD 0.37, 95% CI 0.26,0.49), KCCQ (SMD 0.53,95% CI 0.48, 0.58), SF physical summary (SMD 0.55, 95% CI 0.31 - 0.78) and SF mental summary (SMD 0.34, 95% CI 0.27 - 0.40). At one year there was no statistically significant difference between any of these QoL metrics. For NYHA, no significant difference in odds ratio of class III/IV was observed at one month between TAVI and SAVR (OR 0.94, 95% CI 0.83, 1.07), however, TAVI was associated with reduced odds ratio of NYHA class I/II at one year (OR 0.87, 95% CI 0.78, 0.98). CONCLUSION: Both groups were associated with improvements in QoL and functional outcomes with TAVI reporting more significant improvements in QoL at one-month post-procedures. No significant improvements between groups were seen at one year. This is the largest meta-analysis comparing post-operative health-related quality of life outcomes post SAVR and TAVI and has major implications in shared decision making for the treatment of aortic stenosis.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Qualidade de Vida , Implante de Prótese de Valva Cardíaca/efeitos adversos , Resultado do Tratamento , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Fatores de Risco
14.
Behav Cogn Psychother ; 51(6): 660, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37309672

RESUMO

The subject of prolonged, complicated and traumatic grief has become more topical as a consequence of the Covid-19 pandemic. CBT practitioners have been asked to provide effective therapeutic responses for clients with enduring distressing grief reactions. These enduring grief conditions have now been categorised as Prolonged Grief Disorder in the two main mental health classification systems: in the ICD -11 in November 2020 and as a revision to the DSM-5 in 2021. In this paper we draw on our research and clinical experience in applying cognitive therapy for PTSD (CT-PTSD) to traumatic bereavement to derive lessons for the treatment of prolonged grief. During the pandemic the authors of this paper delivered several workshops on prolonged grief disorder (PGD) during which clinicians raised several thought-provoking questions; how do we differentiate between normal and abnormal or pathological grief; how do we categorise pathological grief; how effective are existing therapies and is there a role for CBT; and how do our experiences with Cognitive Therapy for PTSD help with conceptualisation and treatment of PGD. The purpose of this paper is to answer these important questions and in so doing, consider the historical and theoretical concepts relating to complex and traumatic grief, factors that differentiate normal grief from abnormal grief, maintenance factors for PGD and implications for CBT treatments.


Assuntos
Luto , Terapia Cognitivo-Comportamental , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtorno do Luto Prolongado , Pandemias , Pesar , Cognição , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/psicologia
15.
Infect Immun ; 90(2): e0043521, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34871039

RESUMO

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), a diverse family of multidomain proteins expressed on the surface of malaria-infected erythrocytes, is an important target of protective immunity against malaria. Our group recently studied transcription of the var genes encoding PfEMP1 in individuals from Papua, Indonesia, with severe or uncomplicated malaria. We cloned and expressed domains from 32 PfEMP1s, including 22 that were upregulated in severe malaria and 10 that were upregulated in uncomplicated malaria, using a wheat germ cell-free expression system. We used Luminex technology to measure IgG antibodies to these 32 domains and control proteins in 63 individuals (11 children). At presentation to hospital, levels of antibodies to PfEMP1 domains were either higher in uncomplicated malaria or were not significantly different between groups. Using principal component analysis, antibodies to 3 of 32 domains were highly discriminatory between groups. These included two domains upregulated in severe malaria, a DBLß13 domain and a CIDRα1.6 domain (which has been previously implicated in severe malaria pathogenesis), and a DBLδ domain that was upregulated in uncomplicated malaria. Antibody to control non-PfEMP1 antigens did not differ with disease severity. Antibodies to PfEMP1 domains differ with malaria severity. Lack of antibodies to locally expressed PfEMP1 types, including both domains previously associated with severe malaria and newly identified targets, may in part explain malaria severity in Papuan adults.


Assuntos
Malária Falciparum , Malária , Adulto , Anticorpos Antiprotozoários , Criança , Eritrócitos , Humanos , Indonésia , Proteínas de Membrana/genética , Plasmodium falciparum/genética , Proteínas de Protozoários/genética
16.
Breast Cancer Res Treat ; 195(2): 105-115, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35908121

RESUMO

BACKGROUND: MYC is one of the most frequently altered driver genes in triple-negative breast cancer (TNBC). The aim of this study was to evaluate targeting MYC for the treatment of TNBC. METHODS: The anti-proliferative and apoptosis-inducing effects of the recently discovered MYC inhibitor, MYCi975 were investigated in a panel of 14 breast cancer cell lines representing the main molecular forms of breast cancer. RESULTS: IC50 values for growth inhibition by MYCi975 varied from 2.49 to 7.73 µM. Response was inversely related to endogenous MYC levels as measured by western blotting (p = 0.047, r = - 0.5385) or ELISA (p = 0.001, r = - 0.767), i.e., response to MYCi975 decreased as endogenous MYC levels increased. MYCi975 also induced variable levels of apoptosis across the panel of cell lines, ranging from no detectable induction to 80% induction. Inhibition of proliferation and induction of apoptosis were greater in TNBC than in non-TNBC cell lines (p = 0.041 and p = 0.001, respectively). Finally, combined treatment with MYCi975 and either paclitaxel or doxorubicin resulted in enhanced cell growth inhibition. DISCUSSION: Our findings open the possibility of targeting MYC for the treatment of TNBC. Based on our results, we suggest that trials use a combination of MYCi975 and either docetaxel or doxorubicin and include MYC as a putative therapy predictive biomarker.


Assuntos
Neoplasias de Mama Triplo Negativas , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Doxorrubicina , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
17.
Clin Chem ; 68(11): 1381-1390, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-35962648

RESUMO

BACKGROUND: Protein-based biomarkers are widely used in monitoring patients with diagnosed cancer. These biomarkers however, lack specificity for cancer and have poor sensitivity in detecting early recurrences and monitoring therapy effectiveness. Emerging data suggest that the use of circulating tumor DNA (ctDNA) has several advantages over standard biomarkers. CONTENT: Following curative-intent surgery for cancer, the presence of ctDNA is highly predictive of early disease recurrence, while in metastatic cancer an early decline in ctDNA following the initiation of treatment is predictive of good outcome. Compared with protein biomarkers, ctDNA provides greater cancer specificity and sensitivity for detecting early recurrent/metastatic disease. Thus, in patients with surgically resected colorectal cancer, multiple studies have shown that ctDNA is superior to carcinoembryonic antigen (CEA) in detecting residual disease and early recurrence. Similarly, in breast cancer, ctDNA was shown to be more accurate than carbohydrate antigen 15-3 (CA 15-3) in detecting early recurrences. Other advantages of ctDNA over protein biomarkers in monitoring cancer patients include a shorter half-life in plasma and an ability to predict likely response to specific therapies and identify mechanisms of therapy resistance. However, in contrast to proteins, ctDNA biomarkers are more expensive to measure, less widely available, and have longer turnaround times for reporting. Furthermore, ctDNA assays are less well standardized. SUMMARY: Because of their advantages, it is likely that ctDNA measurements will enter clinical use in the future, where they will complement existing biomarkers and imaging in managing patients with cancer. Hopefully, these combined approaches will lead to a better outcome for patients.


Assuntos
Neoplasias da Mama , DNA Tumoral Circulante , Humanos , Feminino , Biomarcadores Tumorais , Recidiva Local de Neoplasia/genética
18.
Clin Chem ; 68(6): 837-847, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35312747

RESUMO

BACKGROUND: OncoMasTR is a recently developed multigene prognostic test for early-stage breast cancer. The test has been developed in a kit-based format for decentralized deployment in molecular pathology laboratories. The analytical performance characteristics of the OncoMasTR test are described in this study. METHODS: Expression levels of 6 genes were measured by 1-step reverse transcription-quantitative PCR on RNA samples prepared from formalin-fixed, paraffin-embedded (FFPE) breast tumor specimens. Assay precision, reproducibility, input range, and interference were determined using FFPE-derived RNA samples representative of low and high prognostic risk scores. A pooled RNA sample derived from 6 FFPE breast tumor specimens was used to establish the linear range, limit of detection, and amplification efficiency of the individual gene expression assays. RESULTS: The overall precision of the OncoMasTR test was high with an SD of 0.16, which represents less than 2% of the 10-unit risk score range. Test results were reproducible across 4 testing sites, with correlation coefficients of 0.94 to 0.96 for the continuous risk score and concordance of 86% to 96% in low-/high-risk sample classification. Consistent risk scores were obtained across a > 100-fold RNA input range. Individual gene expression assays were linear up to quantification cycle values of 36.0 to 36.9, with amplification efficiencies of 80% to 102%. Test results were not influenced by agents used during RNA isolation, by low levels of copurified genomic DNA, or by moderate levels of copurified adjacent nontumor tissue. CONCLUSION: The OncoMasTR prognostic test displays robust analytical performance that is suitable for deployment by local pathology laboratories for decentralized use.


Assuntos
Neoplasias da Mama , Biomarcadores Tumorais/genética , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Formaldeído , Perfilação da Expressão Gênica/métodos , Humanos , Inclusão em Parafina , Prognóstico , RNA/análise , Receptores de Estrogênio/metabolismo , Reprodutibilidade dos Testes
19.
Am J Forensic Med Pathol ; 43(1): 73-75, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35113818

RESUMO

ABSTRACT: Myocarditis can focally or diffusely involve the myocardium and is associated with arrhythmia, cardiac failure, and sudden death. The majority of cases of myocarditis are lymphocytic in etiology, and neutrophilic myocarditis is relatively uncommon. Although reported in lymphocytic myocarditis, isolated/focal neutrophilic myocarditis of the atrium causing death is not reported in the postmortem literature, and its postmortem computed tomography correlation is not documented. We report a fatal case of isolated neutrophilic atrial myocarditis affecting only the left atrium in a 33-year-old woman presenting as a sudden unexpected death. Microscopy of the left atrium, a not commonly sampled area of the heart, showed florid neutrophilic myocarditis with the remaining right atrium, conduction system, and both ventricles uninvolved. Similar to previously reported fatal isolated atrial lymphocytic myocarditis, postmortem computed tomography was unable to detect any atrial abnormalities. This case highlights a potential "blind spot" for both routine postmortem imaging and examination.


Assuntos
Miocardite , Adulto , Autopsia , Causas de Morte , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Miocardite/diagnóstico por imagem , Miocárdio , Tomografia Computadorizada por Raios X
20.
Int J Cancer ; 148(1): 8-17, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32638380

RESUMO

RAS, TP53 (p53) and MYC are among the most frequently altered driver genes in cancer. Thus, RAS is the most frequently mutated oncogene, MYC the most frequently amplified gene and TP53 the most frequently mutated tumor suppressor gene and overall the most frequently mutated gene in cancer. Theoretically, therefore, these genes are highly attractive targets for cancer treatment. However, as the protein products of each of these genes lack an accessible hydrophobic pocket into which low molecular weight compounds might bind with high affinity, they have proved difficult to target and have traditionally been referred to as "undruggable." Despite this branding, several low molecular weight compounds targeting each of these proteins have recently been reported to have anticancer activity in preclinical models. Indeed, several drugs inhibiting mutant KRAS, MYC overexpression or reactivating mutant p53 have undergone or are currently undergoing clinical trials. For targeting mutant KRAS and reactivating mutant p53, trials have progressed to a Phase III stage, that is, the mutant-p53 reactivating drug, APR-246 is currently being investigated in patients with myelodysplastic syndrome (MDS) and the RAS inhibitor, rigosertib is also undergoing evaluation in patients with MDS. Although there appears to be no directly acting MYC inhibitor currently being tested in a clinical trial, an anti-MYC compound, known as OmoMYC has been extensively validated in multiple preclinical models and is being developed for clinical evaluation. Based on current evidence, the traditional perception of RAS, p53 and MYC as being "undruggable" would appear to be coming to an end.


Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteína Supressora de Tumor p53/agonistas , Animais , Antineoplásicos/uso terapêutico , Sítios de Ligação , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Mutação , Neoplasias/genética , Proteínas Proto-Oncogênicas c-myc/química , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas p21(ras)/química , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética
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