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2.
Clin Lung Cancer ; 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39304361

RESUMO

BACKGROUND: Lung cancer in Australia contributes 9% of all new cancer diagnoses and is the leading cause of cancer death and burden. Clinical practice guidelines provide evidence-based treatment recommendations for best practice management. We aimed to determine the extent of delivery of guideline-concordant treatment (GCT) and to identify modifiable variables influencing receipt of GCT and survival. METHODS: Data was sourced from the Victorian Lung Cancer Registry (VLCR) in Victoria, Australia. Descriptive statistics were used to summarize patient and disease characteristics according to treatment type: GCT versus non-GCT versus no/declined treatment. Statistical analyses included multiple logistic regression, multiple COX regression and Kaplan-Meier survival estimates. RESULTS: 52% of patients were treated with GCT, 32.8% non-GCT and 15.2% declined or received no treatment. GCT treated patients were younger, never smoked, had no comorbidities, had better performance status, had early stage cancer, were discussed at a multidisciplinary meeting or had treatment at a higher volume hospital. Overall, patients that received GCT had a 24% lower risk of mortality compared to patients that received non-GCT. CONCLUSION: Modifiable variables impacting likelihood of receiving GCT included age, smoking status and treating hospital characteristics. Several modifiable variables were identified with positive impacts on survival including increased treatment of the elderly, smoking cessation, delivery of GCT, and treatment in higher volume hospitals. The measurement and reporting of delivery of GCT has positive impacts on survival and therefore merits consideration as an evidence-based quality indicator in the reporting of lung cancer quality and safety outcomes.

3.
Heart Lung Circ ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39306552

RESUMO

Intraoperative fluorescence imaging using indocyanine green (ICG) is an innovative and safe tool in minimally invasive thoracic surgery. It provides real-time imaging capabilities that can enhance surgical precision. We describe several clinical uses of ICG including intersegmental plane identification, thoracic duct injury localisation, anomalous systemic artery identification in pulmonary sequestration, phrenic nerve identification, and sentinel lymph node mapping. Successful visualisation of ICG was achieved to identify intra-thoracic anatomical structures and boundaries, allowing for safe and precise dissection.

4.
Respirology ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138009

RESUMO

BACKGROUND AND OBJECTIVE: Approximately 16,000 new cases of lung cancer are diagnosed each year in Australia and Aotearoa New Zealand, and it is the leading cause of cancer death in the region. Unwarranted variation in lung cancer care and outcomes has been described for many years, although clinical quality indicators to facilitate benchmarking across Australasia have not been established. The purpose of this study was to establish clinical quality indicators applicable to lung and other thoracic cancers across Australia and Aotearoa New Zealand. METHODS: Following a literature review, a modified three round eDelphi consensus process was completed between October 2022 and June 2023. Participants included clinicians from all relevant disciplines, patient advocates, researchers and other stakeholders, with representatives from all Australian states and territories and Aotearoa New Zealand. Consensus was set at a threshold of 70%, with the first two rounds conducted as online surveys, and the final round held as a hybrid in person and virtual consensus meeting. RESULTS: The literature review identified 422 international thoracic oncology indicators, and a total of 71 indicators were evaluated over the course of the Delphi consensus. Ultimately, 27 clinical quality indicators reached consensus, covering the continuum of thoracic oncologic care from diagnosis to first line treatment. Indicators benchmarking supportive care were poorly represented. Attendant numeric quality standards were developed to facilitate benchmarking. CONCLUSION: Twenty-seven clinical quality indicators relevant to thoracic oncology care in Australasia were developed. Real world implementation will now be explored utilizing a prospective dataset collected across Australia.

5.
Cancer Med ; 13(14): e70006, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39001673

RESUMO

INTRODUCTION: Abnormal results in common blood tests may occur several months before lung cancer (LC) and colorectal cancer (CRC) diagnosis. Identifying early blood markers of cancer and distinct blood test signatures could support earlier diagnosis in general practice. METHODS: Using linked Australian primary care and hospital cancer registry data, we conducted a cohort study of 855 LC and 399 CRC patients diagnosed between 2001 and 2021. Requests and results from general practice blood tests (six acute phase reactants [APR] and six red blood cell indices [RBCI]) were examined in the 2 years before cancer diagnosis. Poisson regression models were used to estimate monthly incidence rates and examine pre-diagnostic trends in blood test use and abnormal results prior to cancer diagnosis, comparing patterns in LC and CRC patients. RESULTS: General practice blood test requests increase from 7 months before CRC and 6 months before LC diagnosis. Abnormalities in many APR and RBCI tests increase several months before cancer diagnosis, often occur prior to or in the absence of anaemia (in 51% of CRC and 81% of LC patients with abnormalities), and are different in LC and CRC patients. CONCLUSIONS: This study demonstrates an increase in diagnostic activity in Australian general practice several months before LC and CRC diagnosis, indicating potential opportunities for earlier diagnosis. It identifies blood test abnormalities and distinct signatures that are early markers of LC and CRC. If combined with other pre-diagnostic information, these blood tests have potential to support GPs in prioritising patients for cancer investigation of different sites to expedite diagnosis.


Assuntos
Neoplasias Colorretais , Testes Hematológicos , Neoplasias Pulmonares , Atenção Primária à Saúde , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/sangue , Neoplasias Colorretais/epidemiologia , Austrália/epidemiologia , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Testes Hematológicos/métodos , Testes Hematológicos/estatística & dados numéricos , Detecção Precoce de Câncer/métodos , Sistema de Registros , Biomarcadores Tumorais/sangue , Adulto , Incidência , Idoso de 80 Anos ou mais
6.
Cell ; 187(18): 4981-4995.e14, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39059381

RESUMO

Plasmodium falciparum reticulocyte-binding protein homolog 5 (RH5) is the most advanced blood-stage malaria vaccine candidate and is being evaluated for efficacy in endemic regions, emphasizing the need to study the underlying antibody response to RH5 during natural infection, which could augment or counteract responses to vaccination. Here, we found that RH5-reactive B cells were rare, and circulating immunoglobulin G (IgG) responses to RH5 were short-lived in malaria-exposed Malian individuals, despite repeated infections over multiple years. RH5-specific monoclonal antibodies isolated from eight malaria-exposed individuals mostly targeted non-neutralizing epitopes, in contrast to antibodies isolated from five RH5-vaccinated, malaria-naive UK individuals. However, MAD8-151 and MAD8-502, isolated from two malaria-exposed Malian individuals, were among the most potent neutralizers out of 186 antibodies from both cohorts and targeted the same epitopes as the most potent vaccine-induced antibodies. These results suggest that natural malaria infection may boost RH5-vaccine-induced responses and provide a clear strategy for the development of next-generation RH5 vaccines.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antiprotozoários , Antígenos de Protozoários , Vacinas Antimaláricas , Malária Falciparum , Plasmodium falciparum , Humanos , Anticorpos Neutralizantes/imunologia , Plasmodium falciparum/imunologia , Malária Falciparum/imunologia , Malária Falciparum/prevenção & controle , Malária Falciparum/parasitologia , Vacinas Antimaláricas/imunologia , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Proteínas de Protozoários/imunologia , Anticorpos Monoclonais/imunologia , Adulto , Linfócitos B/imunologia , Epitopos/imunologia , Feminino , Mali , Proteínas de Transporte/imunologia , Masculino , Adolescente
7.
Science ; 384(6695): 573-579, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38696577

RESUMO

Neurons on the left and right sides of the nervous system often show asymmetric properties, but how such differences arise is poorly understood. Genetic screening in zebrafish revealed that loss of function of the transmembrane protein Cachd1 resulted in right-sided habenula neurons adopting left-sided identity. Cachd1 is expressed in neuronal progenitors, functions downstream of asymmetric environmental signals, and influences timing of the normally asymmetric patterns of neurogenesis. Biochemical and structural analyses demonstrated that Cachd1 can bind simultaneously to Lrp6 and Frizzled family Wnt co-receptors. Consistent with this, lrp6 mutant zebrafish lose asymmetry in the habenulae, and epistasis experiments support a role for Cachd1 in modulating Wnt pathway activity in the brain. These studies identify Cachd1 as a conserved Wnt receptor-interacting protein that regulates lateralized neuronal identity in the zebrafish brain.


Assuntos
Canais de Cálcio , Habenula , Neurogênese , Neurônios , Via de Sinalização Wnt , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Receptores Frizzled/metabolismo , Receptores Frizzled/genética , Habenula/metabolismo , Habenula/embriologia , Mutação com Perda de Função , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Neurônios/metabolismo , Receptores Wnt/metabolismo , Receptores Wnt/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Canais de Cálcio/genética , Canais de Cálcio/metabolismo
8.
Annu Rev Biomed Data Sci ; 7(1): 155-177, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38723658

RESUMO

Proteins on the surfaces of cells serve as physical connection points to bridge one cell with another, enabling direct communication between cells and cohesive structure. As biomedical research makes the leap from characterizing individual cells toward understanding the multicellular organization of the human body, the binding interactions between molecules on the surfaces of cells are foundational both for computational models and for clinical efforts to exploit these influential receptor pathways. To achieve this grander vision, we must assemble the full interactome of ways surface proteins can link together. This review investigates how close we are to knowing the human cell surface protein interactome. We summarize the current state of databases and systematic technologies to assemble surface protein interactomes, while highlighting substantial gaps that remain. We aim for this to serve as a road map for eventually building a more robust picture of the human cell surface protein interactome.


Assuntos
Comunicação Celular , Proteínas de Membrana , Humanos , Comunicação Celular/fisiologia , Proteínas de Membrana/metabolismo , Mapeamento de Interação de Proteínas/métodos , Membrana Celular/metabolismo
9.
Malar J ; 23(1): 151, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755636

RESUMO

BACKGROUND: Sporozoite invasion of hepatocytes is an essential step in the Plasmodium life-cycle and has similarities, at the cellular level, to merozoite invasion of erythrocytes. In the case of the Plasmodium blood-stage, efforts to identify host-pathogen protein-protein interactions have yielded important insights including vaccine candidates. In the case of sporozoite-hepatocyte invasion, the host-pathogen protein-protein interactions involved are poorly understood. METHODS: To gain a better understanding of the protein-protein interaction between the sporozoite ligands and host receptors, a systematic screen was performed. The previous Plasmodium falciparum and human surface protein ectodomain libraries were substantially extended, resulting in the creation of new libraries comprising 88 P. falciparum sporozoite protein coding sequences and 182 sequences encoding human hepatocyte surface proteins. Having expressed recombinant proteins from these sequences, a plate-based assay was used, capable of detecting low affinity interactions between recombinant proteins, modified for enhanced throughput, to screen the proteins for interactions. The novel interactions identified in the screen were characterized biochemically, and their essential role in parasite invasion was further elucidated using antibodies and genetically manipulated Plasmodium parasites. RESULTS: A total of 7540 sporozoite-hepatocyte protein pairs were tested under conditions capable of detecting interactions of at least 1.2 µM KD. An interaction between the human fibroblast growth factor receptor 4 (FGFR4) and the P. falciparum protein Pf34 is identified and reported here, characterizing its affinity and demonstrating the blockade of the interaction by reagents, including a monoclonal antibody. Furthermore, further interactions between Pf34 and a second P. falciparum rhoptry neck protein, PfRON6, and between human low-density lipoprotein receptor (LDLR) and the P. falciparum protein PIESP15 are identified. Conditional genetic deletion confirmed the essentiality of PfRON6 in the blood-stage, consistent with the important role of this protein in parasite lifecycle. Pf34 was refractory to attempted genetic modification. Antibodies to Pf34 abrogated the interaction and had a modest effect upon sporozoite invasion into primary human hepatocytes. CONCLUSION: Pf34 and PfRON6 may be members of a functionally important invasion complex which could be a target for future interventions. The modified interaction screening assay, protein expression libraries and P. falciparum mutant parasites reported here may be a useful tool for protein interaction discovery and antigen candidate screening which could be of wider value to the scientific community.


Assuntos
Hepatócitos , Plasmodium falciparum , Proteínas de Protozoários , Esporozoítos , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Hepatócitos/parasitologia , Humanos , Esporozoítos/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Interações Hospedeiro-Patógeno , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Interações Hospedeiro-Parasita , Ligação Proteica
10.
mBio ; 15(5): e0085924, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639536

RESUMO

Visceral leishmaniasis is a deadly infectious disease and is one of the world's major neglected health problems. Because the symptoms of infection are similar to other endemic diseases, accurate diagnosis is crucial for appropriate treatment. Definitive diagnosis using splenic or bone marrow aspirates is highly invasive, and so, serological assays are preferred, including the direct agglutination test (DAT) or rK39 strip test. These tests, however, are either difficult to perform in the field (DAT) or lack specificity in some endemic regions (rK39), making the development of new tests a research priority. The availability of Leishmania spp. genomes presents an opportunity to identify new diagnostic targets. Here, we use genome data and a mammalian protein expression system to create a panel of 93 proteins consisting of the extracellular ectodomains of the Leishmania donovani cell surface and secreted proteins. We use these panel and sera from murine experimental infection models and natural human and canine infections to identify new candidates for serological diagnosis. We observed a concordance between the most immunoreactive antigens in different host species and transmission settings. The antigen encoded by the LdBPK_323600.1 gene can diagnose Leishmania infections with high sensitivity and specificity in patient cohorts from different endemic regions including Bangladesh and Ethiopia. In longitudinal sampling of treated patients, we observed reductions in immunoreactivity to LdBPK_323600.1 suggesting it could be used to diagnose treatment success. In summary, we have identified new antigens that could contribute to improved serological diagnostic tests to help control the impact of this deadly tropical infectious disease. IMPORTANCE: Visceral leishmaniasis is fatal if left untreated with patients often displaying mild and non-specific symptoms during the early stages of infection making accurate diagnosis important. Current methods for diagnosis require highly trained medical staff to perform highly invasive biopsies of the liver or bone marrow which pose risks to the patient. Less invasive molecular tests are available but can suffer from regional variations in their ability to accurately diagnose an infection. To identify new diagnostic markers of visceral leishmaniasis, we produced and tested a panel of 93 proteins identified from the genome of the parasite responsible for this disease. We found that the pattern of host antibody reactivity to these proteins was broadly consistent across naturally acquired infections in both human patients and dogs, as well as experimental rodent infections. We identified a new protein called LdBPK_323600.1 that could accurately diagnose visceral leishmaniasis infections in humans.


Assuntos
Anticorpos Antiprotozoários , Antígenos de Protozoários , Leishmania donovani , Leishmaniose Visceral , Proteínas de Protozoários , Testes Sorológicos , Leishmania donovani/genética , Leishmania donovani/imunologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Animais , Humanos , Camundongos , Cães , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Testes Sorológicos/métodos , Biomarcadores/sangue , Feminino , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Camundongos Endogâmicos BALB C , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Sensibilidade e Especificidade , Doenças do Cão/diagnóstico , Doenças do Cão/parasitologia
11.
Intern Med J ; 54(7): 1119-1125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38560767

RESUMO

BACKGROUND: Malignant pleural effusions (MPEs) are common, and a third of them have underlying trapped lung (TL). Management of MPE and TL is suspected to be heterogeneous. Understanding current practices in Australasia is important in guiding policies and future research. AIMS: Electronic survey of Australia-New Zealand respiratory physicians, thoracic surgeons and their respective trainees to determine practice of MPE and TL management. RESULTS: Of the 132 respondents, 56% were respiratory physicians, 23% were surgeons and 20% were trainees. Many respondents defined TL as >25% or any level of incomplete lung expansion; 75% would use large-volume thoracentesis to determine whether TL was present. For patients with TL, indwelling pleural catheters (IPCs) were the preferred treatment irrespective of prognosis. In those without TL, surgical pleurodesis was the most common choice if prognosis was >6 months, whereas IPC was the preferred option if survival was <3 months. Only 5% of respondents considered decortication having a definite role in TL, but 55% would consider it in select cases. Forty-nine per cent of surgeons would not perform decortication when the lung does not fully expand intra-operatively. Perceived advantages of IPCs were minimisation of hospital time, effusion re-intervention and usefulness irrespective of TL status. Perceived disadvantages of IPCs were lack of suitable drainage care, potentially indefinite duration of catheter-in-situ and catheter complications. CONCLUSION: This survey highlights the lack of definition of TL and heterogeneity of MPE management in Australasia, especially for patients with expandable lungs. This survey also identified the main hurdles of IPC use that should be targeted.


Assuntos
Derrame Pleural Maligno , Humanos , Derrame Pleural Maligno/terapia , Inquéritos e Questionários , Australásia , Cirurgiões , Pleurodese , Nova Zelândia , Austrália , Padrões de Prática Médica/estatística & dados numéricos , Toracentese , Cateteres de Demora , Cirurgia Torácica
13.
Elife ; 132024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666763

RESUMO

A crucial event in sexual reproduction is when haploid sperm and egg fuse to form a new diploid organism at fertilization. In mammals, direct interaction between egg JUNO and sperm IZUMO1 mediates gamete membrane adhesion, yet their role in fusion remains enigmatic. We used AlphaFold to predict the structure of other extracellular proteins essential for fertilization to determine if they could form a complex that may mediate fusion. We first identified TMEM81, whose gene is expressed by mouse and human spermatids, as a protein having structural homologies with both IZUMO1 and another sperm molecule essential for gamete fusion, SPACA6. Using a set of proteins known to be important for fertilization and TMEM81, we then systematically searched for predicted binary interactions using an unguided approach and identified a pentameric complex involving sperm IZUMO1, SPACA6, TMEM81 and egg JUNO, CD9. This complex is structurally consistent with both the expected topology on opposing gamete membranes and the location of predicted N-glycans not modeled by AlphaFold-Multimer, suggesting that its components could organize into a synapse-like assembly at the point of fusion. Finally, the structural modeling approach described here could be more generally useful to gain insights into transient protein complexes difficult to detect experimentally.


Assuntos
Proteínas de Membrana , Animais , Masculino , Camundongos , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/química , Espermatozoides/fisiologia , Espermatozoides/metabolismo , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Imunoglobulinas/química , Interações Espermatozoide-Óvulo/fisiologia , Feminino
14.
BMJ Open ; 14(3): e076797, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508629

RESUMO

Long-term outcome and 'health-related quality of life' (HRQoL) following hospitalisation for COVID-19-related severe acute respiratory infection (SARI) is limited. OBJECTIVE: To assess the impact of HRQoL in patients hospitalised with COVID-19-related SARI at 1 year post discharge, focusing on the potential impact of age, frailty, and disease severity. METHOD: Routinely collected outcome data on 1207 patients admitted with confirmed COVID-19 related SARI across all three secondary care sites in our NHS trust over 3 months were assessed in this retrospective cohort study. Of those surviving 1 year, we prospectively collected 36-item short form (SF-36) HRQoL questionnaires, comparing three age groups (<49, 49-69, and the over 69-year-olds), the relative impact of frailty (using the Clinical Frailty Score; CFS), and disease severity (using National Early Warning Score; NEWS) on HRQoL domains. RESULTS: Overall mortality was 46.5% in admitted patients. In our SF-36 cohort (n=169), there was a significant reduction in all HRQoL domains versus normative data; the most significant reductions were in the physical component (p<0.001) across all ages and the emotional component (p<0.01) in the 49-69 year age group, with age having no additional impact on HRQoL. However, there was a significant correlation between physical well-being versus CFS (the correlation coefficient=-0.37, p<0.05), though not NEWS, with no gender difference observed. CONCLUSION: There was a significant reduction in all SF-36 domains at 1 year. Poor CFS at admission was associated with a significant and prolonged impact on physical parameters at 1 year. Age had little impact on the severity of HRQoL, except in the domains of physical functioning and the overall physical component.


Assuntos
COVID-19 , Fragilidade , Humanos , Qualidade de Vida/psicologia , Estudos Retrospectivos , Alta do Paciente , Fragilidade/complicações , COVID-19/complicações , Assistência ao Convalescente , Hospitalização , Gravidade do Paciente
15.
Sci Adv ; 10(8): eadk6352, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38381819

RESUMO

Fertilization involves the recognition and fusion of sperm and egg to form a previously unidentified organism. In mammals, surface molecules on the sperm and egg have central roles, and while adhesion is mediated by the IZUMO1-JUNO sperm-egg ligand-receptor pair, the molecule/s responsible for membrane fusion remain mysterious. Recently, MAIA/FCRL3 was identified as a mammalian egg receptor, which bound IZUMO1 and JUNO and might therefore have a bridging role in gamete recognition and fusion. Here, we use sensitive assays designed to detect extracellular protein binding to investigate the interactions between MAIA and both IZUMO1 and JUNO. Despite using reagents with demonstrable biochemical activity, we did not identify any direct binding between MAIA/FCRL3 and either IZUMO1 or JUNO. We also observed no fusogenic activity of MAIA/FCRL3 in a cell-based membrane fusion assay. Our findings encourage caution in further investigations on the role played by MAIA/FCRL3 in fertilization.


Assuntos
Proteínas de Membrana , Receptores Fc , Animais , Humanos , Masculino , Imunoglobulinas/genética , Imunoglobulinas/análise , Imunoglobulinas/química , Ligantes , Mamíferos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/química , Sêmen/metabolismo , Interações Espermatozoide-Óvulo , Espermatozoides/metabolismo
16.
Proc Natl Acad Sci U S A ; 121(5): e2316304121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38261617

RESUMO

The discovery that Africans were resistant to infection by Plasmodium vivax (P. vivax) led to the conclusion that P. vivax invasion relied on the P. vivax Duffy Binding Protein (PvDBP) interacting with the Duffy Antigen Receptor for Chemokines (DARC) expressed on erythrocytes. However, the recent reporting of P. vivax infections in DARC-negative Africans suggests that the parasite might use an alternate invasion pathway to infect DARC-negative reticulocytes. To identify the parasite ligands and erythrocyte receptors that enable P. vivax invasion of both DARC-positive and -negative erythrocytes, we expressed region II containing the Duffy Binding-Like (DBL) domain of P. vivax erythrocyte binding protein (PvEBP-RII) and verified that the DBL domain binds to both DARC-positive and -negative erythrocytes. Furthermore, an AVidity-based EXtracelluar Interaction Screening (AVEXIS) was used to identify the receptor for PvEBP among over 750 human cell surface receptor proteins, and this approach identified only Complement Receptor 1 (CR1, CD35, or C3b/C4b receptor) as a PvEBP receptor. CR1 is a well-known receptor for P. falciparum Reticulocyte binding protein Homology 4 (PfRh4) and is present on the surfaces of both reticulocytes and normocytes, but its expression decreases as erythrocytes age. Indeed, PvEBP-RII bound to a subpopulation of both reticulocytes and normocytes, and this binding was blocked by the addition of soluble CR1 recombinant protein, indicating that CR1 is the receptor of PvEBP. In addition, we found that the Long Homology Repeat A (LHR-A) subdomain of CR1 is the only subdomain responsible for mediating the interaction with PvEBP-RII.


Assuntos
Malária Falciparum , Plasmodium vivax , Humanos , Receptores de Superfície Celular , Eritrócitos , Reticulócitos , Antígenos CD2 , Moléculas de Adesão Celular
17.
Nat Commun ; 14(1): 4619, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528099

RESUMO

Invasion of red blood cells (RBCs) by Plasmodium merozoites is critical to their continued survival within the host. Two major protein families, the Duffy binding-like proteins (DBPs/EBAs) and the reticulocyte binding like proteins (RBLs/RHs) have been studied extensively in P. falciparum and are hypothesized to have overlapping, but critical roles just prior to host cell entry. The zoonotic malaria parasite, P. knowlesi, has larger invasive merozoites and contains a smaller, less redundant, DBP and RBL repertoire than P. falciparum. One DBP (DBPα) and one RBL, normocyte binding protein Xa (NBPXa) are essential for invasion of human RBCs. Taking advantage of the unique biological features of P. knowlesi and iterative CRISPR-Cas9 genome editing, we determine the precise order of key invasion milestones and demonstrate distinct roles for each family. These distinct roles support a mechanism for phased commitment to invasion and can be targeted synergistically with invasion inhibitory antibodies.


Assuntos
Malária , Parasitos , Plasmodium knowlesi , Animais , Humanos , Proteínas de Transporte/metabolismo , Parasitos/metabolismo , Malária/parasitologia , Plasmodium knowlesi/genética , Plasmodium knowlesi/metabolismo , Proteínas de Protozoários/metabolismo , Eritrócitos/parasitologia , Merozoítos/metabolismo , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo
18.
Eur J Pharmacol ; 958: 176010, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37634841

RESUMO

In decompensated cirrhosis, the severity of portal hypertension (PHT) is associated with increased hepatic endothelial nitric oxide synthase (eNOS) trafficking inducer (Nostrin), but the mechanism remains unclear. AIM: To investigate: (1) Whether in cirrhosis-PHT models, ± superimposed inflammation to mimic acute-on-chronic liver failure (ACLF) modulates hepatic nitric oxide synthase trafficking inducer (NOSTRIN) expression, nitric oxide (NO) synthesis, and/or endothelial dysfunction (ED); and (2) Whether the "angiotensin II type 1 receptor blocker" candesartan cilexetil (CC) affects this pathway. CD-1 mice received intraperitoneal carbon tetrachloride injections (CCl4 15% v/v in corn oil, 0.5 mL/kg) twice weekly for 12 wk to induce cirrhosis. After 12 wk, mice were randomized to receive 2-wk oral administration of CC (8 mg/kg) ± LPS. At sacrifice, plasma (biochemical indicators, cytokines, and angiotensin II) and liver tissues (histopathology, Sirius-red stains, and molecular studies) were analysed. Moreover, Nostrin gene knockdown was tested in human umbilical vein endothelial cells (HUVECs). When compared to naïve animals, CCl4-treated animals showed markedly elevated hepatic Nostrin expression (P < 0.0001), while hepatic peNOS expression (measure of eNOS activity) was significantly reduced (P < 0.05). LPS challenge further increased Nostrin and reduced peNOS expression (P < 0.05 for both) in cirrhotic animals. Portal pressure and subsequent hepatic vascular resistance were also increased in all cirrhotic animals following LPS challenge. In CCl4 ± LPS-treated animals, CC treatment significantly reduced Nostrin (P < 0.05) and increased hepatic cGMP (P < 0.01). NOSIP, caveolin-1, NFκB, and iNOS protein expression were significantly increased in CCl4-treated animals (P < 0.05 for all). CC treatment non-significantly lowered NOSIP and caveolin-1 expression while iNOS and NFκB expression was significantly reduced in CCl4 + LPS-treated animals (P < 0.05 for both). Furthermore, Nostrin knockdown significantly improved peNOS expression and associated NO synthesis and reduced inflammation in HUVECs. This study is the first to indicate a potential mechanistic role for the Nostrin-eNOS-NO pathway in cirrhosis and ACLF development. Moreover, this pathway provides a potential therapeutic target given the ameliorative response to Candesartan treatment.


Assuntos
Insuficiência Hepática Crônica Agudizada , Hipertensão Portal , Animais , Humanos , Camundongos , Insuficiência Hepática Crônica Agudizada/complicações , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Caveolina 1/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células Endoteliais/metabolismo , Hipertensão Portal/complicações , Hipertensão Portal/tratamento farmacológico , Inflamação/complicações , Lipopolissacarídeos , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , NF-kappa B/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Pressão na Veia Porta
19.
J Hepatol ; 79(1): 79-92, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37268222

RESUMO

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is characterized by severe systemic inflammation, multi-organ failure and high mortality rates. Its treatment is an urgent unmet need. DIALIVE is a novel liver dialysis device that aims to exchange dysfunctional albumin and remove damage- and pathogen-associated molecular patterns. This first-in-man randomized-controlled trial was performed with the primary aim of assessing the safety of DIALIVE in patients with ACLF, with secondary aims of evaluating its clinical effects, device performance and effect on pathophysiologically relevant biomarkers. METHODS: Thirty-two patients with alcohol-related ACLF were included. Patients were treated with DIALIVE for up to 5 days and end points were assessed at Day 10. Safety was assessed in all patients (n = 32). The secondary aims were assessed in a pre-specified subgroup that had at least three treatment sessions with DIALIVE (n = 30). RESULTS: There were no significant differences in 28-day mortality or occurrence of serious adverse events between the groups. Significant reduction in the severity of endotoxemia and improvement in albumin function was observed in the DIALIVE group, which translated into a significant reduction in the CLIF-C (Chronic Liver Failure consortium) organ failure (p = 0.018) and CLIF-C ACLF scores (p = 0.042) at Day 10. Time to resolution of ACLF was significantly faster in DIALIVE group (p = 0.036). Biomarkers of systemic inflammation such as IL-8 (p = 0.006), cell death [cytokeratin-18: M30 (p = 0.005) and M65 (p = 0.029)], endothelial function [asymmetric dimethylarginine (p = 0.002)] and, ligands for Toll-like receptor 4 (p = 0.030) and inflammasome (p = 0.002) improved significantly in the DIALIVE group. CONCLUSIONS: These data indicate that DIALIVE appears to be safe and impacts positively on prognostic scores and pathophysiologically relevant biomarkers in patients with ACLF. Larger, adequately powered studies are warranted to further confirm its safety and efficacy. IMPACT AND IMPLICATIONS: This is the first-in-man clinical trial which tested DIALIVE, a novel liver dialysis device for the treatment of cirrhosis and acute-on-chronic liver failure, a condition associated with severe inflammation, organ failures and a high risk of death. The study met the primary endpoint, confirming the safety of the DIALIVE system. Additionally, DIALIVE reduced inflammation and improved clinical parameters. However, it did not reduce mortality in this small study and further larger clinical trials are required to re-confirm its safety and to evaluate efficacy. CLINICAL TRIAL NUMBER: NCT03065699.


Assuntos
Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Humanos , Insuficiência Hepática Crônica Agudizada/terapia , Insuficiência Hepática Crônica Agudizada/complicações , Padrão de Cuidado , Prognóstico , Diálise Renal/efeitos adversos , Cirrose Hepática/complicações , Biomarcadores , Inflamação/complicações
20.
ANZ J Surg ; 93(6): 1543-1550, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37106553

RESUMO

BACKGROUND: To review the outcomes of surgically resected lung neuroendocrine neoplasms (LNEN) at a tertiary referral centre and to validate a previously published LNEN-specific staging system (NETL). METHODS: All patients who were identified on histopathology to have LNEN were included. Pre-, intra- and post-operative outcomes were collected, including long-term survival. Patients were staged by both the TNM (seventh and eighth edition) and NETL staging (seventh and eighth edition definitions). Kaplan-Meier (KM) survival analysis was performed according to histopathology and stage, along with uni- and multivariate analyses. RESULT: A total of 132 patients were included in the study, with a median age of 65 years; 55% were female. Typical carcinoid (TC) was the most common pathology (53.4%) followed by large cell neuroendocrine carcinoma (LCNEC - 23.5%), atypical carcinoid (AC - 20.5%) and small cell carcinoma (3.0%). The most common operation performed was a lobectomy (55.3%). Overall survival at 5 years was 80% (100% TC, 78.2% AC, LCNEC 40.9%) and 5-year disease free survival was 76.8% (TC 94.3%, AC 56.8%, LCNEC 56.4%). KM curves showed a trend towards NETL performing better than TNM, however, in multivariate analysis only the histological subtype was found to be significant in our study. CONCLUSION: This is the largest known Australian series of LNEN to date, showing survival comparable to international outcomes. We have demonstrated large variations in outcome, driven by histological grade. The TNM system does not correlate with survival and we have not been able to show that currently proposed NETL staging is superior.


Assuntos
Tumor Carcinoide , Carcinoma Neuroendócrino , Neoplasias Pulmonares , Tumores Neuroendócrinos , Humanos , Feminino , Idoso , Masculino , Austrália , Neoplasias Pulmonares/patologia , Carcinoma Neuroendócrino/cirurgia , Carcinoma Neuroendócrino/patologia , Tumores Neuroendócrinos/cirurgia , Tumores Neuroendócrinos/patologia , Tumor Carcinoide/cirurgia , Tumor Carcinoide/patologia , Pulmão/patologia , Estadiamento de Neoplasias , Prognóstico
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