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1.
ACS Appl Bio Mater ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970152

RESUMO

INTRODUCTION: The demand for red blood cells (RBCs) is on the rise due to the increasing diagnosis of chronic diseases such as sickle cell anemia, malaria, and thalassemia. Despite many commercial attempts, there are no U.S. FDA-approved artificial RBCs for use in humans. Existing RBC substitutes have employed various strategies to transport oxygen, extend the circulation time, and reduce organ toxicity, but none have replicated the natural protective mechanisms of RBCs, which prevent hemoglobin (Hb) dimerization and heme iron oxidation. Lumbricus terrestris (earthworm) erythrocruorin (LtEc) is a naturally occurring extracellular hemoglobin (Hb) with promising attributes: large molecular diameter (30 nm), high molecular weight (3.6 MDa), low auto-oxidation rate, and limited nitric oxide-scavenging properties. These characteristics make LtEc an ideal candidate as an RBC substitute. However, LtEc has a significant drawback, its short circulatory half-life. To address this issue, we explored thiol-mediated surface PEGylation of LtEc (PEG-LtEc) at varying polyethylene glycol (PEG) surface coverages. Increasing PEG surface coverage beyond 40% destabilizes LtEc into smaller subunits that are 1/12th the size of LtEc. Therefore, we evaluated two PEG surface coverage options: PEG-LtEc-0.2 (20% PEGylation) and PEG-LtEc-1.0 (100% PEGylation). METHODS: We conducted experiments using golden Syrian hamsters with dorsal window chambers and catheters to assess the efficacy of these solutions. We measured microvascular parameters, organ function, cerebral blood flow, circulation time, mean arterial pressure, heart rate, and blood gases and performed histology to screen for toxicity. CONCLUSION: Our findings indicate that both PEG-LtEc molecules offer significant benefits in restoring microvascular parameters, organ function, cerebral blood flow, and circulation time compared to LtEc alone. Notably, PEG-LtEc-1.0 showed superior microvascular perfusion, although it exhibited a higher rate of auto-oxidation compared to PEG-LtEc-0.2. These results underscore the advantages of PEGylation in terms of tissue perfusion and organ health while highlighting its limitations.

2.
Adv Sci (Weinh) ; : e2402464, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38952077

RESUMO

Phase transitions are typically quantified using order parameters, such as crystal lattice distances and radial distribution functions, which can identify subtle changes in crystalline materials or high-contrast phases with large structural differences. However, the identification of phases with high complexity, multiscale organization and of complex patterns during the structural fluctuations preceding phase transitions, which are essential for understanding the system pathways between phases, is challenging for those traditional analyses. Here, it is shown that for two model systems- thermotropic liquid crystals and a lyotropic water/surfactant mixtures-graph theoretical (GT) descriptors can successfully identify complex phases combining molecular and nanoscale levels of organization that are hard to characterize with traditional methodologies. Furthermore, the GT descriptors also reveal the pathways between the different phases. Specifically, centrality parameters and node-based fractal dimension quantify the system behavior preceding the transitions, capturing fluctuation-induced breakup of aggregates and their long-range cooperative interactions. GT parameterization can be generalized for a wide range of chemical systems and be instrumental for the growth mechanisms of complex nanostructures.

3.
bioRxiv ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38948791

RESUMO

Background: The renin-angiotensin system involves many more enzymes, receptors and biologically active peptides than originally thought. With this study, we investigated whether angiotensin-(1-5) [Ang-(1-5)], a 5-amino acid fragment of angiotensin II, has biological activity, and through which receptor it elicits effects. Methods: The effect of Ang-(1-5) (1µM) on nitric oxide release was measured by DAF-FM staining in human aortic endothelial cells (HAEC), or Chinese Hamster Ovary (CHO) cells stably transfected with the angiotensin AT 2 -receptor (AT 2 R) or the receptor Mas. A potential vasodilatory effect of Ang-(1-5) was tested in mouse mesenteric and human renal arteries by wire myography; the effect on blood pressure was evaluated in normotensive C57BL/6 mice by Millar catheter. These experiments were performed in the presence or absence of a range of antagonists or inhibitors or in AT 2 R-knockout mice. Binding of Ang-(1-5) to the AT 2 R was confirmed and the preferred conformations determined by in silico docking simulations. The signaling network of Ang-(1-5) was mapped by quantitative phosphoproteomics. Results: Key findings included: (1) Ang-(1-5) induced activation of eNOS by changes in phosphorylation at Ser1177 eNOS and Tyr657 eNOS and thereby (2) increased NO release from HAEC and AT 2 R-transfected CHO cells, but not from Mas-transfected or non-transfected CHO cells. (3) Ang-(1-5) induced relaxation of preconstricted mouse mesenteric and human renal arteries and (4) lowered blood pressure in normotensive mice - effects which were respectively absent in arteries from AT 2 R-KO or in PD123319-treated mice and which were more potent than effects of the established AT 2 R-agonist C21. (5) According to in silico modelling, Ang-(1-5) binds to the AT 2 R in two preferred conformations, one differing substantially from where the first five amino acids within angiotensin II bind to the AT 2 R. (6) Ang-(1-5) modifies signaling pathways in a protective RAS-typical way and with relevance for endothelial cell physiology and disease. Conclusions: Ang-(1-5) is a potent, endogenous AT 2 R-agonist.

4.
J Vis Exp ; (208)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949382

RESUMO

Lung transplantation is hampered by the lack of suitable donors. Previously, donors that were thought to be marginal or inadequate were discarded. However, new and exciting technology, such as ex vivo lung perfusion (EVLP), offers lung transplant providers extended assessment for marginal donor allografts. This dynamic assessment platform has led to an increase in lung transplantation and has allowed providers to use donors that were previously discarded, thus expanding the donor pool. Current perfusion techniques use cellular or acellular perfusates, and both have distinct advantages and disadvantages. Perfusion composition is critical to maintaining a homeostatic environment, providing adequate metabolic support, decreasing inflammation and cellular death, and ultimately improving organ function. Perfusion solutions must contain sufficient protein concentration to maintain appropriate oncotic pressure. However, current perfusion solutions often lead to fluid extravasation through the pulmonary endothelium, resulting in inadvertent pulmonary edema and damage. Thus, it is necessary to develop novel perfusion solutions that prevent excessive damage while maintaining proper cellular homeostasis. Here, we describe the application of a polymerized human hemoglobin (PolyhHb)-based oxygen carrier as a perfusate and the protocol in which this perfusion solution can be tested in a model of rat EVLP. The goal of this study is to provide the lung transplant community with key information in designing and developing novel perfusion solutions, as well as the proper protocols to test them in clinically relevant translational transplant models.


Assuntos
Hemoglobinas , Transplante de Pulmão , Pulmão , Perfusão , Animais , Ratos , Transplante de Pulmão/métodos , Hemoglobinas/química , Perfusão/métodos , Pulmão/metabolismo , Humanos , Oxigênio/metabolismo , Substitutos Sanguíneos/farmacologia , Substitutos Sanguíneos/química , Masculino , Soluções para Preservação de Órgãos/química
5.
Mol Imaging ; 23: 15353508241245265, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952398

RESUMO

This meeting report summarizes a consultants meeting that was held at International Atomic Energy Agency Headquarters, Vienna, in July 2022 to provide an update on the development of multimodality imaging by combining nuclear medicine imaging agents with other nonradioactive molecular probes and/or biomedical imaging techniques.


Assuntos
Imagem Multimodal , Medicina Nuclear , Medicina Nuclear/métodos , Medicina Nuclear/tendências , Imagem Multimodal/métodos , Humanos
6.
Neurosci Biobehav Rev ; 164: 105807, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38981573

RESUMO

The efficacy and acceptability of various non-invasive brain stimulation (NIBS) interventions for autism spectrum disorder remain unclear. We carried out a systematic review for randomized controlled trials (RCTs) regarding NIBS for reducing autistic symptoms (INPLASY202370003). Sixteen articles (N = 709) met the inclusion criteria for network meta-analysis. Effect sizes were reported as standardized mean differences (SMDs) or odds ratios with 95 % confidence intervals (CIs). Fourteen active NIBS interventions, including transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation, and transcranial pulse stimulation were analyzed. Only anodal tDCS over the left dorsolateral prefrontal cortex paired with cathodal tDCS over an extracephalic location (atDCS_F3 + ctDCS_E) significantly improved autistic symptoms compared to sham controls (SMD = - 1.40, 95 %CIs = - 2.67 to - 0.14). None of the NIBS interventions markedly improved social-communication symptoms or restricted/repetitive behaviors in autistic participants. Moreover, no active NIBS interventions exhibited significant dropout rate differences compared to sham controls, and no serious adverse events were reported for any intervention.

7.
BMJ Open Respir Res ; 11(1)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019625

RESUMO

INTRODUCTION: Contemporary data on the burden of chronic respiratory diseases in sub-Saharan Africa is limited. More so, their economic burden is not well described. This study aims to establish a chronic respiratory disease observatory for Africa. Specific study aims are (1) to describe the prevalence and determinants of asthma with a target to screen up to 4000 children and adolescents across four African cities; (2) to determine the prevalence and determinants of chronic obstructive pulmonary disease (COPD) with a target to screen up to 3000 adults (≥18 years) across five African cities; (3) to describe the disease burden by assessing the frequency and severity of symptoms and exacerbations, medication use, emergency healthcare utilisation and hospitalisation; and (4) to assess the economic burden and affordability of the medicines for these diseases. METHODS AND ANALYSIS: Surveys will be conducted in schools to identify children and adolescents with asthma using the Global Asthma Network screening questionnaire in Ghana, Nigeria, the Democratic Republic of Congo, and Uganda. Community surveys will be conducted among adults using an adapted version of the Burden of Obstructive Lung Disease Questionnaire to identify persons with COPD symptoms in Nigeria, Burkina Faso, Mozambique, Rwanda, and Sierra Leone. Fractional exhaled nitric oxide and pre-bronchodilator and post-bronchodilator spirometry will be done for children with asthma or asthma symptoms and for all adult participants. Children and adults with respiratory symptoms or diagnoses will complete the health economic questionnaires. Statistical analysis will involve descriptive and analytical statistics to determine outcomes. ETHICS AND DISSEMINATION: Ethical approval has been obtained from participating institutions. This study's results will inform deliberations at the United Nations General Assembly high-level meeting on non-communicable diseases in 2025. The results will be shared through academic conferences and journals and communicated to the schools and the communities.


Assuntos
Asma , Efeitos Psicossociais da Doença , Doença Pulmonar Obstrutiva Crônica , Humanos , Asma/epidemiologia , Asma/economia , Asma/terapia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/economia , Doença Pulmonar Obstrutiva Crônica/terapia , Prevalência , Adolescente , Criança , Adulto , Feminino , Masculino , Inquéritos e Questionários , África/epidemiologia , Adulto Jovem , Projetos de Pesquisa , África Subsaariana/epidemiologia
8.
PLoS One ; 19(6): e0305125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38861560

RESUMO

BACKGROUND: Small airways obstruction (SAO) has been associated with occupational exposures. Whether exposure to harmful occupational agents impacts the survival of people with SAO is unknown. Our aim was to estimate the mortality risk associated with occupational exposures among people with SAO. METHODS: We used data from UK Biobank participants with SAO, defined as a ratio of forced expiratory volume in three seconds to forced expiratory volume in six seconds (FEV3/FEV6) below the lower limit of normal. We assigned lifetime occupational exposures to participants with available occupational histories using the ALOHA+ Job Exposure Matrix. Mortality data were provided by the National Death Registries. We used Cox regression to assess the association of all-cause mortality with lifetime occupational exposures (vapours, gases, dusts, fumes-VGDF; solvents; pesticides; metals), adjusting for potential confounders. RESULTS: The 13,942 participants with SAO had a mean age of 56±7 years, 59% were females and 94.2% were of White ancestry. Overall, there were 457 deaths over a median follow-up of 12.8 years. A greater mortality risk was associated with exposure to VGDF, with hazard ratios of 1.32 (95%CI: 1.04-1.78) for low levels and 1.41 (95%CI: 1.11-1.78) for moderate levels of cumulative exposure. There was no evidence of association for the other occupational exposures. CONCLUSION: Lifetime occupational exposure to VGDF in people with SAO may have a detrimental effect on their survival. Future respiratory health surveillance programmes of people exposed to VGDF should consider assessment for SAO and focus on primary prevention through adequate exposure control.


Assuntos
Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Feminino , Masculino , Pessoa de Meia-Idade , Obstrução das Vias Respiratórias/mortalidade , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/epidemiologia , Fatores de Risco , Modelos de Riscos Proporcionais , Idoso , Adulto , Reino Unido/epidemiologia , Volume Expiratório Forçado
10.
Dalton Trans ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38938129

RESUMO

Palladium(II) complexes have stimulated research interest mainly due to their in vitro cytotoxicity against various cancer cell lines and their low cytotoxicity in healthy cells. Thus, in this work, we combined Pd(II)/phosphine systems with the natural product curcumin as a ligand, obtaining a series of complexes, [Pd(cur)(PPh3)2]PF6 (A1), [Pd(cur)(dppe)]PF6 (A2), [Pd(cur)(dppp)]PF6 (A3), [Pd(cur)(dppb)]PF6 (A4) and [Pd(cur)(dppf)]PF6 (A5), where dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphosphino)propane, dppb = 1,4-bis(diphenylphosphino)butane, and dppf = 1,1'-bis(diphenylphosphino)ferrocene (P-P), which were characterized by elemental analysis, molar conductivity analysis, and mass, NMR (1H, 13C, 31P{1H}), UV-vis, and IR spectroscopies, and four of them (A1, A2, A4, and A5) by X-ray crystallography. The in vitro cell viability of the complexes A1-A5, cisplatin, and the free ligand curcumin against MDA-MB-231 (human triple-negative breast tumor cells), SK-BR-3 (human breast tumor cells), A549 (human lung tumor cells), MRC-5 (non-tumor human lung cells), A2780 (human ovarian carcinoma cells), and A2780cis (cisplatin-resistant human ovarian carcinoma cells), was evaluated by the MTT colorimetric assay. For the tumor cell lines tested, the complexes showed good anticancer activities. The results showed that in general the complexes had lower IC50 values than free curcumin and the precursors [PdCl2(P-P)]. IC50 results obtained for the A1-A5 complexes, in the MCF-7 cell line, are similar to those that had already been observed for some Pd/bipy/curcumin complexes. In the MDA-MB-231 cell line, complexes A1 and A5 stood out, with their lowest IC50 values, around 5 µmol L-1, and the complexes appeared to be more active (lower IC50 values) against the ovarian cell lines. Complex A1 was 23 and 22-fold more cytotoxic than cisplatin, against the A2780 and A2780cis cells, respectively. The complex A1 was studied on A2780cis cells and it was found that this complex inhibits colony formation and induces cell cycle arrest in the sub-G1 phase in a concentration-dependent manner and leads to cell death by apoptosis. The DCFDA assay revealed a potent ROS induction for complex A1.

11.
Ann Oncol ; 35(7): 588-606, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38834388

RESUMO

BACKGROUND: Advancements in the field of precision medicine have prompted the European Society for Medical Oncology (ESMO) Precision Medicine Working Group to update the recommendations for the use of tumour next-generation sequencing (NGS) for patients with advanced cancers in routine practice. METHODS: The group discussed the clinical impact of tumour NGS in guiding treatment decision using the ESMO Scale for Clinical Actionability of molecular Targets (ESCAT) considering cost-effectiveness and accessibility. RESULTS: As for 2020 recommendations, ESMO recommends running tumour NGS in advanced non-squamous non-small-cell lung cancer, prostate cancer, colorectal cancer, cholangiocarcinoma, and ovarian cancer. Moreover, it is recommended to carry out tumour NGS in clinical research centres and under specific circumstances discussed with patients. In this updated report, the consensus within the group has led to an expansion of the recommendations to encompass patients with advanced breast cancer and rare tumours such as gastrointestinal stromal tumours, sarcoma, thyroid cancer, and cancer of unknown primary. Finally, ESMO recommends carrying out tumour NGS to detect tumour-agnostic alterations in patients with metastatic cancers where access to matched therapies is available. CONCLUSION: Tumour NGS is increasingly expanding its scope and application within oncology with the aim of enhancing the efficacy of precision medicine for patients with cancer.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias , Medicina de Precisão , Humanos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento de Nucleotídeos em Larga Escala/normas , Medicina de Precisão/métodos , Medicina de Precisão/normas , Neoplasias/genética , Neoplasias/patologia , Neoplasias/terapia , Oncologia/métodos , Oncologia/normas , Europa (Continente)
12.
Biomater Adv ; 162: 213931, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38924805

RESUMO

Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (≈70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.


Assuntos
Alginatos , Antibacterianos , Escherichia coli , Poliésteres , Staphylococcus aureus , Infecção dos Ferimentos , Alginatos/química , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Antibacterianos/administração & dosagem , Poliésteres/química , Ampicilina/farmacologia , Ampicilina/uso terapêutico , Ampicilina/química , Humanos , Hidrogéis/química , Polietilenoglicóis/química , Animais , Bandagens , Testes de Sensibilidade Microbiana , Camundongos , Cicatrização/efeitos dos fármacos
13.
Psychiatry Res ; 338: 115979, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38850891

RESUMO

The depression response trajectory after a course of repetitive transcranial magnetic stimulation(rTMS) remains understudied. We searched for blinded randomized controlled trials(RCTs) that examined conventional rTMS over left dorsolateral prefrontal cortex(DLPFC) for major depressive episodes(MDE). The effect size was calculated as the difference in depression improvement, between active and sham rTMS. We conducted a random-effects dose-response meta-analysis to model the response trajectory from the beginning of rTMS to the post-treatment follow-up phase. The area under curve (AUC) of the first 8-week response trajectory was calculated to compare antidepressant efficacy between different rTMS protocols. We included 40 RCTs(n = 2012). The best-fitting trajectory model exhibited a logarithmic curve(X2=17.7, P < 0.001), showing a gradual ascent with tapering off around the 3-4th week mark and maintaining until week 16. The maximum effect size was 6.1(95 %CI: 1.25-10.96) at week 16. The subgroup analyses showed distinct trajectories across different rTMS protocols. Besides, the comparisons of AUC showed that conventional rTMS protocols with more pulse/session group or more total pulses were associated with greater efficacy than those with fewer pulse/session or fewer total pulses, respectively. A course of conventional left DLPFC rTMS could lead to both acute antidepressant effects and sustained after-effects, which were modeled by different rTMS protocols in MDE.


Assuntos
Transtorno Depressivo Maior , Córtex Pré-Frontal Dorsolateral , Estimulação Magnética Transcraniana , Humanos , Transtorno Depressivo Maior/terapia , Estimulação Magnética Transcraniana/métodos , Córtex Pré-Frontal Dorsolateral/fisiologia , Córtex Pré-Frontal , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
BMJ Open ; 14(6): e071136, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38889936

RESUMO

INTRODUCTION: Observational studies are fraught with several biases including reverse causation and residual confounding. Overview of reviews of observational studies (ie, umbrella reviews) synthesise systematic reviews with or without meta-analyses of cross-sectional, case-control and cohort studies, and may also aid in the grading of the credibility of reported associations. The number of published umbrella reviews has been increasing. Recently, a reporting guideline for overviews of reviews of healthcare interventions (Preferred Reporting Items for Overviews of Reviews (PRIOR)) was published, but the field lacks reporting guidelines for umbrella reviews of observational studies. Our aim is to develop a reporting guideline for umbrella reviews on cross-sectional, case-control and cohort studies assessing epidemiological associations. METHODS AND ANALYSIS: We will adhere to established guidance and prepare a PRIOR extension for systematic reviews of cross-sectional, case-control and cohort studies testing epidemiological associations between an exposure and an outcome, namely Preferred Reporting Items for Umbrella Reviews of Cross-sectional, Case-control and Cohort studies (PRIUR-CCC). Step 1 will be the project launch to identify stakeholders. Step 2 will be a literature review of available guidance to conduct umbrella reviews. Step 3 will be an online Delphi study sampling 100 participants among authors and editors of umbrella reviews. Step 4 will encompass the finalisation of PRIUR-CCC statement, including a checklist, a flow diagram, explanation and elaboration document. Deliverables will be (i) identifying stakeholders to involve according to relevant expertise and end-user groups, with an equity, diversity and inclusion lens; (ii) completing a narrative review of methodological guidance on how to conduct umbrella reviews, a narrative review of methodology and reporting in published umbrella reviews and preparing an initial PRIUR-CCC checklist for Delphi study round 1; (iii) preparing a PRIUR-CCC checklist with guidance after Delphi study; (iv) publishing and disseminating PRIUR-CCC statement. ETHICS AND DISSEMINATION: PRIUR-CCC has been approved by The Ottawa Health Science Network Research Ethics Board and has obtained consent (20220639-01H). Participants to step 3 will give informed consent. PRIUR-CCC steps will be published in a peer-reviewed journal and will guide reporting of umbrella reviews on epidemiological associations.


Assuntos
Guias como Assunto , Humanos , Estudos Transversais , Estudos de Coortes , Estudos de Casos e Controles , Projetos de Pesquisa/normas , Revisões Sistemáticas como Assunto , Lista de Checagem , Estudos Observacionais como Assunto
15.
mBio ; 15(7): e0116624, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38934618

RESUMO

Contemporary antifungal therapies utilized to treat filamentous fungal infections are inhibited by intrinsic and emerging drug resistance. Consequently, there is an urgent need to develop novel antifungal compounds that are effective against drug-resistant filamentous fungi. Here, we utilized an Aspergillus fumigatus cell-based high-throughput screen to identify small molecules with antifungal activity that also potentiated triazole activity. The screen identified 16 hits with promising activity against A. fumigatus. A nonspirocyclic piperidine, herein named MBX-7591, exhibited synergy with triazole antifungal drugs and activity against pan-azole-resistant A. fumigatus isolates. MBX-7591 has additional potent activity against Rhizopus species and CO2-dependent activity against Cryptococcus neoformans. Chemical, genetic, and biochemical mode of action analyses revealed that MBX-7591 increases cell membrane saturation by decreasing oleic acid content. MBX-7591 has low toxicity in vivo and shows good efficacy in decreasing fungal burden in a murine model of invasive pulmonary aspergillosis. Taken together, our results suggest MBX-7591 is a promising hit with a novel mode of action for further antifungal drug development to combat the rising incidence of triazole-resistant filamentous fungal infections.IMPORTANCEThe incidence of infections caused by fungi continues to increase with advances in medical therapies. Unfortunately, antifungal drug development has not kept pace with the incidence and importance of fungal infections, with only three major classes of antifungal drugs currently available for use in the clinic. Filamentous fungi, also called molds, are particularly recalcitrant to contemporary antifungal therapies. Here, a recently developed Aspergillus fumigatus cell reporter strain was utilized to conduct a high-throughput screen to identify small molecules with antifungal activity. An emphasis was placed on small molecules that potentiated the activity of contemporary triazole antifungals and led to the discovery of MBX-7591. MBX-7591 potentiates triazole activity against drug-resistant molds such as A. fumigatus and has activity against Mucorales fungi. MBX-7591's mode of action involves inhibiting the conversion of saturated to unsaturated fatty acids, thereby impacting fungal membrane integrity. MBX-7591 is a novel small molecule with antifungal activity poised for lead development.


Assuntos
Antifúngicos , Aspergillus fumigatus , Farmacorresistência Fúngica , Ácidos Graxos Insaturados , Testes de Sensibilidade Microbiana , Triazóis , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Antifúngicos/farmacologia , Triazóis/farmacologia , Camundongos , Animais , Ácidos Graxos Insaturados/farmacologia , Humanos , Ensaios de Triagem em Larga Escala , Sinergismo Farmacológico , Rhizopus/efeitos dos fármacos , Rhizopus/genética , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/genética , Piperidinas/farmacologia , Modelos Animais de Doenças , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Aspergilose Pulmonar Invasiva/microbiologia
16.
Pharmacol Rev ; 76(3): 323-357, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697859

RESUMO

Over the last six decades, lithium has been considered the gold standard treatment for the long-term management of bipolar disorder due to its efficacy in preventing both manic and depressive episodes as well as suicidal behaviors. Nevertheless, despite numerous observed effects on various cellular pathways and biologic systems, the precise mechanism through which lithium stabilizes mood remains elusive. Furthermore, there is recent support for the therapeutic potential of lithium in other brain diseases. This review offers a comprehensive examination of contemporary understanding and predominant theories concerning the diverse mechanisms underlying lithium's effects. These findings are based on investigations utilizing cellular and animal models of neurodegenerative and psychiatric disorders. Recent studies have provided additional support for the significance of glycogen synthase kinase-3 (GSK3) inhibition as a crucial mechanism. Furthermore, research has shed more light on the interconnections between GSK3-mediated neuroprotective, antioxidant, and neuroplasticity processes. Moreover, recent advancements in animal and human models have provided valuable insights into how lithium-induced modifications at the homeostatic synaptic plasticity level may play a pivotal role in its clinical effectiveness. We focused on findings from translational studies suggesting that lithium may interface with microRNA expression. Finally, we are exploring the repurposing potential of lithium beyond bipolar disorder. These recent findings on the therapeutic mechanisms of lithium have provided important clues toward developing predictive models of response to lithium treatment and identifying new biologic targets. SIGNIFICANCE STATEMENT: Lithium is the drug of choice for the treatment of bipolar disorder, but its mechanism of action in stabilizing mood remains elusive. This review presents the latest evidence on lithium's various mechanisms of action. Recent evidence has strengthened glycogen synthase kinase-3 (GSK3) inhibition, changes at the level of homeostatic synaptic plasticity, and regulation of microRNA expression as key mechanisms, providing an intriguing perspective that may help bridge the mechanistic gap between molecular functions and its clinical efficacy as a mood stabilizer.


Assuntos
Compostos de Lítio , Humanos , Animais , Compostos de Lítio/farmacologia , Compostos de Lítio/uso terapêutico , Antimaníacos/farmacologia , Antimaníacos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Plasticidade Neuronal/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores
17.
Adv Healthc Mater ; : e2400622, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820600

RESUMO

Virion-mediated outbreaks are imminent and despite rapid responses, continue to cause adverse symptoms and death. Therefore, tunable, sensitive, high-throughput assays are needed to help diagnose future virion-mediated outbreaks. Herein, it is developed a tunable in situ assay to selectively enrich virions and extracellular vesicles (EVs) and simultaneously detect antigens and nucleic acids at a single-particle resolution. The Biochip Antigen and RNA Assay (BARA) enhanced sensitivities compared to quantitative reverse-transcription polymerase chain reaction (qRT-PCR), enabling the detection of virions in asymptomatic patients, genetic mutations in single virions, and enabling the continued long-term expression of viral RNA in the EV-enriched subpopulation in the plasma of patients with post-acute sequelae of the coronavirus disease of 2019 (COVID-19). BARA revealed highly accurate diagnoses of COVID-19 by simultaneously detecting the spike glycoprotein and nucleocapsid-encoding RNA in saliva and nasopharyngeal swab samples. Altogether, the single-particle detection of antigens and viral RNA provides a tunable framework for the diagnosis, monitoring, and mutation screening of current and future outbreaks.

18.
Biomed Pharmacother ; 176: 116789, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815289

RESUMO

The widespread adoption of high-calorie, high-fat, high-sucrose diets (HFHSD) has become a global health concern, particularly due to their association with cardiovascular diseases and metabolic disorders. These comorbidities increase susceptibility to severe outcomes from viral infections and trauma, with trauma-related incidents significantly contributing to global mortality rates. This context underscores the critical need for a reliable blood supply. Recent research has focused on high molecular weight (MW) polymerized human hemoglobin (PolyhHb) as a promising alternative to red blood cells (RBCs), showing encouraging outcomes in previous studies. Given the overlap of metabolic disorders and trauma-related health issues, it is crucial to assess the potential toxicity of PolyhHb transfusions, particularly in models that represent these vulnerable populations. This study evaluated the effects of PolyhHb exchange transfusion in guinea pigs that had developed metabolic disorders due to a 12-week HFHSD regimen. The guinea pigs, underwent a 20 % blood volume exchange transfusion with either PolyhHb or the lower molecular weight polymerized bovine hemoglobin, Oxyglobin. Results revealed that both PolyhHb and Oxyglobin transfusions led to liver damage, with a more pronounced effect observed in HFHSD-fed animals. Additionally, markers of cardiac dysfunction indicated signs of cardiac injury in both the HFHSD and normal diet groups following the Oxyglobin transfusion. This study highlights how pre-existing metabolic disorders can exacerbate the potential side effects of hemoglobin-based oxygen carriers (HBOCs). Importantly, the newer generation of high MW PolyhHb showed lower cardiac toxicity compared to the earlier generation low MW PolyhHb, known as Oxyglobin, even in models with pre-existing endothelial and metabolic challenges.


Assuntos
Doenças Cardiovasculares , Hemoglobinas , Doenças Metabólicas , Peso Molecular , Animais , Hemoglobinas/metabolismo , Hemoglobinas/farmacologia , Cobaias , Masculino , Modelos Animais de Doenças , Dieta Hiperlipídica/efeitos adversos , Humanos , Substitutos Sanguíneos/farmacologia
19.
Ann Oncol ; 35(7): 630-642, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38755096

RESUMO

BACKGROUND: Immune checkpoint inhibitors improve the efficacy of first-line chemotherapy for patients with programmed death-ligand 1 (PD-L1)-positive unresectable locally advanced/metastatic triple-negative breast cancer (aTNBC), but randomised data in rapidly relapsing aTNBC are scarce. PATIENTS AND METHODS: IMpassion132 (NCT03371017) enrolled patients with aTNBC relapsing <12 months after last chemotherapy dose (anthracycline and taxane required) or surgery for early TNBC. PD-L1 status was centrally assessed using SP142 before randomisation. Initially patients were enrolled irrespective of PD-L1 status. From August 2019, enrolment was restricted to PD-L1-positive (tumour immune cell ≥1%) aTNBC. Patients were randomised 1:1 to placebo or atezolizumab 1200 mg every 21 days with investigator-selected chemotherapy until disease progression or unacceptable toxicity. Stratification factors were chemotherapy regimen (carboplatin plus gemcitabine or capecitabine monotherapy), visceral (lung and/or liver) metastases and (initially) PD-L1 status. The primary endpoint was overall survival (OS), tested hierarchically in patients with PD-L1-positive tumours and then, if positive, in the modified intent-to-treat (mITT) population (all-comer patients randomised pre-August 2019). Secondary endpoints included progression-free survival (PFS), objective response rate (ORR) and safety. RESULTS: Among 354 patients with rapidly relapsing PD-L1-positive aTNBC, 68% had a disease-free interval of <6 months and 73% received carboplatin/gemcitabine. The OS hazard ratio was 0.93 (95% confidence interval 0.73-1.20, P = 0.59; median 11.2 months with placebo versus 12.1 months with atezolizumab). mITT and subgroup results were consistent. Median PFS was 4 months across treatment arms and populations. ORRs were 28% with placebo versus 40% with atezolizumab. Adverse events (predominantly haematological) were similar between arms and as expected with atezolizumab plus carboplatin/gemcitabine or capecitabine following recent chemotherapy exposure. CONCLUSIONS: OS, which is dismal in patients with TNBC relapsing within <12 months, was not improved by adding atezolizumab to chemotherapy. A biology-based definition of intrinsic resistance to immunotherapy in aTNBC is urgently needed to develop novel therapies for these patients in next-generation clinical trials.


Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Gencitabina , Recidiva Local de Neoplasia , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Método Duplo-Cego , Idoso , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Adulto , Carboplatina/administração & dosagem , Capecitabina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Intervalo Livre de Progressão , Inibidores de Checkpoint Imunológico/administração & dosagem , Inibidores de Checkpoint Imunológico/efeitos adversos
20.
ESMO Open ; 9(5): 103443, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692082

RESUMO

BACKGROUND: The purpose of this study was to evaluate the prognostic value of the multigene EndoPredict test in prospectively collected data of patients screened for the randomized, double-blind, phase III UNIRAD trial, which evaluated the addition of everolimus to adjuvant endocrine therapy in high-risk, hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer. PATIENTS AND METHODS: Patients were classified into low or high risk according to the EPclin score, consisting of a 12-gene molecular score combined with tumor size and nodal status. Association of the EPclin score with disease-free survival (DFS) and distant metastasis-free survival (DMFS) was evaluated using Kaplan-Meier estimates. The independent prognostic added value of EPclin score was tested in a multivariate Cox model after adjusting on tumor characteristics. RESULTS: EndoPredict test results were available for 768 patients: 663 patients classified as EPclin high risk (EPCH) and 105 patients as EPclin low risk (EPCL). Median follow-up was 70 months (range 1-172 months). For the 429 EPCH randomized patients, there was no significant difference in DFS between treatment arms. The 60-month relapse rate for patients in the EPCL and EPCH groups was 0% and 7%, respectively. Hazard ratio (HR) supposing continuous EPclin score was 1.87 [95% confidence interval (CI) 1.4-2.5, P < 0.0001]. This prognostic effect remained significant when assessed in a Cox model adjusting on tumor size, number of positive nodes and tumor grade (HR 1.52, 95% CI 1.09-2.13, P = 0.0141). The 60-month DMFS for patients in the EPCL and EPCH groups was 100% and 94%, respectively (adjusted HR 8.10, 95% CI 1.1-59.1, P < 0.0001). CONCLUSIONS: The results confirm the value of EPclin score as an independent prognostic parameter in node-positive, hormone receptor-positive, HER2-negative early breast cancer patients receiving standard adjuvant treatment. EPclin score can be used to identify patients at higher risk of recurrence who may warrant additional systemic treatments.


Assuntos
Neoplasias da Mama , Receptor ErbB-2 , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Método Duplo-Cego , Idoso , Adulto , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Everolimo/uso terapêutico , Everolimo/farmacologia , Intervalo Livre de Doença , Biomarcadores Tumorais/metabolismo
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