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1.
Afr Health Sci ; 21(2): 735-742, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34795730

RESUMO

Background: Anti-human leukocyte antigen antibodies (anti-HLA) play a crucial role in graft. Detection of anti-HLA, both pre- and post-transplant is a crucial investigation in clinical organ transplantation. Objectives: Three methodologies for the detection of lymphocytotoxic antibodies were compared to establish which of these is best suited to optimise pre-transplant donor-recipient matching. Methods: Serum samples from 15 renal transplant patients were tested for the presence of anti-HLA by i) cytotoxic-dependent cross-match (CDCXM), ii) flow cytometric cross-match (FCXM) and iii) Luminex-based donor specific antibody cross-match (DSAXM) method, Confirmatory tests for the presence of preformed HLA antibodies were tested using Luminex methodology. Results: Two (13%) of the 15 patients had positive HLA Class I antibodies (Ab) using all 3 methods. An additional 2 HLA Class I Ab were identified with FCXM/CDCXM. DSAXM identified 1 HLA Class I positive, not indicated by CDCXM/FCXM.High HLA Class II positivity (40%), identified by CDCXM, while DSAXM and FCXM identified two and one patients, respectively. CDCXM produced 4 false-positive results confirmed by lymphocyte single antigen (LSA) assay. Conclusions: The DSAXM method appears to add value in pre-transplantation screening to identify pre-sensitised patients that may not reject the donor graft due to the absence of donor-specific antibodies.

2.
Front Pharmacol ; 12: 743582, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675810

RESUMO

The development of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, with agents such as nivolumab, pembrolizumab, and cemiplimab targeting programmed cell death protein-1 (PD-1) and durvalumab, avelumab, and atezolizumab targeting PD-ligand 1 (PD-L1). Ipilimumab targets cytotoxic T lymphocyte-associated antigen-4 (CTLA-4). These inhibitors have shown remarkable efficacy in melanoma, lung cancer, urothelial cancer, and a variety of solid tumors, either as single agents or in combination with other anticancer modalities. Additional indications are continuing to evolve. Checkpoint inhibitors are associated with less toxicity when compared to chemotherapy. These agents enhance the antitumor immune response and produce side- effects known as immune-related adverse events (irAEs). Although the incidence of immune checkpoint inhibitor pneumonitis (ICI-Pneumonitis) is relatively low, this complication is likely to cause the delay or cessation of immunotherapy and, in severe cases, may be associated with treatment-related mortality. The primary mechanism of ICI-Pneumonitis remains unclear, but it is believed to be associated with the immune dysregulation caused by ICIs. The development of irAEs may be related to increased T cell activity against cross-antigens expressed in tumor and normal tissues. Treatment with ICIs is associated with an increased number of activated alveolar T cells and reduced activity of the anti-inflammatory Treg phenotype, leading to dysregulation of T cell activity. This review discusses the pathogenesis of alveolar pneumonitis and the incidence, diagnosis, and clinical management of pulmonary toxicity, as well as the pulmonary complications of ICIs, either as monotherapy or in combination with other anticancer modalities, such as thoracic radiotherapy.

3.
Front Genet ; 12: 698875, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394188

RESUMO

Bacteria use K+-uptake transporters differentially for adaptation in varying growth conditions. In Mycobacterium tuberculosis, two K+-uptake systems, the Trk comprising the CeoB and CeoC proteins and the Kdp consisting of the two-component system (TCS), KdpDE and KdpFABC, have been characterized, but their selective utilization during bacterial growth has not been completely explored. In the current study, the roles of the M. tuberculosis KdpDE regulatory system alone and in association with the Trk transporters in bacterial growth were investigated by evaluating the growth of M. tuberculosis KdpDE-deletion and KdpDE/Trk (KT)-double knockout mutant strains in planktonic culture under standard growth conditions. The KT-double knockout mutant strain was first constructed using homologous recombination procedures and was evaluated together with the KdpDE-deletion mutant and the wild-type (WT) strains with respect to their rates of growth, K+-uptake efficiencies, and K+-transporter gene expression during planktonic growth. During growth at optimal K+ concentrations and pH levels, selective deletion of the TCS KdpDE (KdpDE-deletion mutant) led to attenuation of bacterial growth and an increase in bacterial K+-uptake efficiency, as well as dysregulated expression of the kdpFABC and trk genes. Deletion of both the KdpDE and the Trk systems (KT-double knockout) also led to severely attenuated bacterial growth, as well as an increase in bacterial K+-uptake efficiency. These results demonstrate that the KdpDE regulatory system plays a key role during bacterial growth by regulating K+ uptake via modulation of the expression and activities of both the KdpFABC and Trk systems and is important for bacterial growth possibly by preventing cytoplasmic K+ overload.

4.
Front Pharmacol ; 12: 676399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34168563

RESUMO

Lung cancer remains the leading cause of cancer mortality in the United States, with non-small cell lung cancer (NSCLC) accounting for around 85% of cases. Of particular concern is the poor responsiveness of this malignancy to therapy, resulting in a very low 5-year survival rate (17.4%) and a prominent tendency to progress to metastatic disease. A number of very recent studies, both pre-clinical and clinical, have implicated the neutrophil in both the pathogenesis and unsatisfactory response to therapy of NSCLC. In this context, movement of neutrophils into the tumor microenvironment (TME) is a common feature of NSCLC. Indeed neutrophils are the dominant type of immune cell in the NSCLC TME, creating a highly immunosuppressive milieu that is not only conducive to tumor growth and spread, but also represents a significant obstacle to the success of anti-tumor therapy, especially novel immunotherapies. The clinically relevant adverse impact of a neutrophil predominance both systemically and in the TME of patients with NSCLC is underscored by the negative prognostic value of both a persistent neutrophilia and, in particular, a high (≥5) neutrophil:lymphocyte ratio. On a more positive note, however, recognition of the involvement of the neutrophil in both the pathophysiology of NSCLC and treatment failure has enabled identification of neutrophil-targeted strategies that have the potential to serve as adjuncts to standard anti-cancer therapies, including immunotherapy. These strategies together with a consideration of the immunosuppressive, pro-tumorigenic properties of the neutrophil represent the major thrusts of this review.

5.
Pneumonia (Nathan) ; 13(1): 5, 2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33894790

RESUMO

BACKGROUND: It has been recognised for a considerable time-period, that viral respiratory infections predispose patients to bacterial infections, and that these co-infections have a worse outcome than either infection on its own. However, it is still unclear what exact roles co-infections and/or superinfections play in patients with COVID-19 infection. MAIN BODY: This was an extensive review of the current literature regarding co-infections and superinfections in patients with SARS-CoV-2 infection. The definitions used were those of the Centers for Disease Control and Prevention (US), which defines coinfection as one occurring concurrently with the initial infection, while superinfections are those infections that follow on a previous infection, especially when caused by microorganisms that are resistant, or have become resistant, to the antibiotics used earlier. Some researchers have envisioned three potential scenarios of bacterial/SARS-CoV-2 co-infection; namely, secondary SARS-CoV-2 infection following bacterial infection or colonisation, combined viral/bacterial pneumonia, or secondary bacterial superinfection following SARS-CoV-2. There are a myriad of published articles ranging from letters to the editor to systematic reviews and meta-analyses describing varying ranges of co-infection and/or superinfection in patients with COVID-19. The concomitant infections described included other respiratory viruses, bacteria, including mycobacteria, fungi, as well as other, more unusual, pathogens. However, as will be seen in this review, there is often not a clear distinction made in the literature as to what the authors are referring to, whether true concomitant/co-infections or superinfections. In addition, possible mechanisms of the interactions between viral infections, including SARS-CoV-2, and other infections, particularly bacterial infections are discussed further. Lastly, the impact of these co-infections and superinfections in the severity of COVID-19 infections and their outcome is also described. CONCLUSION: The current review describes varying rates of co-infections and/or superinfections in patients with COVID-19 infections, although often a clear distinction between the two is not clear in the literature. When they occur, these infections appear to be associated with both severity of COVID-19 as well as poorer outcomes.

6.
Front Immunol ; 12: 634386, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777022

RESUMO

Neutrophils are important components of the innate immune system that mediate pathogen defense by multiple processes including phagocytosis, release of proteolytic enzymes, production of reactive oxygen species, and neutrophil extracellular trap formation. Abnormalities of neutrophil count and function have been described in the setting of HIV infection, with the majority of antiretroviral agents (ARVs), excluding zidovudine, having been reported to correct neutropenia. Questions still remain, however, about their impact on neutrophil function, particularly the possibility of persistent neutrophil activation, which could predispose people living with HIV to chronic inflammatory disorders, even in the presence of virally-suppressive treatment. In this context, the effects of protease inhibitors and integrase strand transfer inhibitors, in particular, on neutrophil function remain poorly understood and deserve further study. Besides mediating hemostatic functions, platelets are increasingly recognized as critical role players in the immune response against infection. In the setting of HIV, these cells have been found to harbor the virus, even in the presence of antiretroviral therapy (ART) potentially promoting viral dissemination. While HIV-infected individuals often present with thrombocytopenia, they have also been reported to have increased platelet activation, as measured by an upregulation of expression of CD62P (P-selectin), CD40 ligand, glycoprotein IV, and RANTES. Despite ART-mediated viral suppression, HIV-infected individuals reportedly have sustained platelet activation and dysfunction. This, in turn, contributes to persistent immune activation and an inflammatory vascular environment, seemingly involving neutrophil-platelet-endothelium interactions that increase the risk for development of comorbidities such as cardiovascular disease (CVD) that has become the leading cause of morbidity and mortality in HIV-infected individuals on treatment, clearly underscoring the importance of unraveling the possible etiologic roles of ARVs. In this context, abacavir and ritonavir-boosted lopinavir and darunavir have all been linked to an increased risk of CVD. This narrative review is therefore focused primarily on the role of neutrophils and platelets in HIV transmission and disease, as well as on the effect of HIV and the most common ARVs on the numbers and functions of these cells, including neutrophil-platelet-endothelial interactions.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Plaquetas/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , HIV/patogenicidade , Neutrófilos/efeitos dos fármacos , Animais , Plaquetas/imunologia , Plaquetas/metabolismo , Plaquetas/virologia , HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Interações Hospedeiro-Patógeno , Humanos , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/virologia , Ativação Plaquetária/efeitos dos fármacos , Resultado do Tratamento
7.
Curr Opin Oncol ; 33(4): 287-294, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33756517

RESUMO

PURPOSE OF REVIEW: The past decade has witnessed unprecedented delivery to the clinical arena of a range of novel, innovative, and effective targeted anticancer therapies. These include immunotherapies, most prominently immune checkpoint inhibitors, as well as agents that target growth factors and cancer-related mutations. Many of these new cancer therapies are, however, associated with an array of toxicities, necessitating insight and vigilance on the part of attending physicians to achieve high-quality supportive care alongside toxicity management. In this review, we consider some of the key supportive care issues in toxicity management. RECENT FINDINGS: Although both supportive care and targeted therapies have brought significant benefits to cancer care, the management of novel cancer therapy toxicities is nevertheless often complex. This is due in large part to the fact that target organs differ widely, particularly in the case of checkpoint inhibitors, with minor dermatological disorders being most common, while others, such as pneumonitis, are more severe and potentially life threatening. Accordingly, efficient management of these immune-related adverse events requires collaboration between multiple medical specialists. SUMMARY: Supportive care is a key component in the management of new cancer therapy toxicities and needs to be incorporated into treatment pathways.


Assuntos
Neoplasias/terapia , Cuidados Paliativos/métodos , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Humanos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico
8.
Artigo em Inglês | MEDLINE | ID: mdl-33560906

RESUMO

The relationship of various benthic metrics to physical habitat metrics, pyrethroids, metals and sediment parameters was evaluated for a 10 year data set in Pleasant Grove Creek (Roseville, California) using univariate linear models, stepwise multiple regressions, and canonical correlation analysis. In general, total physical habitat scores in this residential stream were considered to be marginal to suboptimal. The most dominant benthic taxa were generally considered to be tolerant of environmental stressors and the benthic communities were rated as impaired based on a benthic index. Potentially toxic sediment concentrations of cadmium, chromium, copper, nickel and zinc were reported at various sites based on a comparison with existing threshold effect levels. The sum of pyrethroid Toxics Units (TUs) indicated that 10 of 21 sites based on a sensitive Hyalella laboratory toxicity test had TUs greater than one thus suggesting toxicity at various sites. In summary, the effects of the physical habitat, as reflected by certain habitat metrics that were indicative of stream-flow, hydrology, habitat diversity, and substrate quality overshadowed any apparent effects of pyrethroids and metals on shaping resident benthic communities when all environmental variables were considered in multivariate analyses.


Assuntos
Ecossistema , Rios , Anfípodes/efeitos dos fármacos , Animais , California , Monitoramento Ambiental , Metais/análise , Metais/toxicidade , Piretrinas/análise , Piretrinas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
9.
Expert Rev Clin Pharmacol ; 14(3): 295-313, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33517803

RESUMO

INTRODUCTION: Patients with hematological and advanced solid malignancies have acquired immune dysfunction, often exacerbated by treatment, posing a significant risk for the development of infections. This review evaluates the utility of current clinical and treatment guidelines, in the setting of management of infections in cancer patients. AREAS COVERED: These include causes of infection in cancer patients, management of patients with high-risk and low-risk febrile neutropenia, management of low-risk patients in an outpatient setting, the role of granulocyte colony-stimulating factor (G-CSF) in the prevention and treatment of neutropenia-related infections, management of lung infections in various clinical settings, and emerging challenges surrounding the risk of infection in cancer patients treated with novel treatments. The literature search was performed by accessing PubMed and other databases, focusing on published clinical trials of relevant anti-cancer agents and diseases, primarily covering the recent past, but also including several key studies published during the last decade and, somewhat earlier in a few cases. EXPERT REVIEW: Notwithstanding the promise of gene therapy/gene editing in hematological malignancies and some types of solid cancers, innovations introduced in clinical practice include more discerning clinical management such as the generalized use of biosimilar formulations of G-CSF and the implementation of novel, innovative immunotherapies.


Assuntos
Neutropenia Febril/complicações , Infecções/terapia , Neoplasias/complicações , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Medicamentos Biossimilares/administração & dosagem , Neutropenia Febril/etiologia , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Imunoterapia/métodos , Infecções/etiologia , Neoplasias/terapia , Guias de Prática Clínica como Assunto
11.
Support Care Cancer ; 29(2): 1129-1138, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33230644

RESUMO

Patients with cancer are at higher risk of more severe COVID-19 infection and have more associated complications. The position paper describes the management of cancer patients, especially those receiving anticancer treatment, during the COVID-19 pandemic. Dyspnea is a common emergency presentation in patients with cancer with a wide range of differential diagnoses, including pulmonary embolism, pleural disease, lymphangitis, and infection, of which SARS-CoV-2 is now a pathogen to be considered. Screening interviews to determine whether patients may be infected with COVID-19 are imperative to prevent the spread of infection, especially within healthcare facilities. Cancer patients testing positive with no or minimal symptoms may be monitored from home. Telemedicine is an option to aid in following patients without potential exposure. Management of complications of systemic anticancer treatment, such as febrile neutropenia (FN), is of particular importance during the COVID-19 pandemic where clinicians aim to minimize patients' risk of infection and need for hospital visits. Outpatient management of patients with low-risk FN is a safe and effective strategy. Although the MASCC score has not been validated in patients with suspected or confirmed SARS-CoV-2, it has nevertheless performed well in patients with a range of infective illnesses and, accordingly, it is reasonable to expect efficacy in the clinical setting of COVID-19. Risk stratification of patients presenting with FN is a vital tenet of the evolving sepsis and pandemic strategy, necessitating access to locally formulated services based on MASCC and other national and international guidelines. Innovative oncology services will need to utilize telemedicine, hospital at home, and ambulatory care services approaches not only to limit the number of hospital visits but also to anticipate the complications of the anticancer treatments.


Assuntos
COVID-19/diagnóstico , Neutropenia Febril/diagnóstico , Febre/etiologia , Neoplasias/complicações , Assistência Ambulatorial , COVID-19/complicações , Neutropenia Febril/etiologia , Neutropenia Febril/terapia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Pandemias , SARS-CoV-2 , Telemedicina
12.
Pharmaceuticals (Basel) ; 13(12)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255391

RESUMO

This study probed the differential utilization of P2Y1 and P2Y12 receptors in mobilizing CD62P (P-selectin) from intracellular granules following activation of human platelets with adenosine 5'-diphosphate (ADP, 100 µmol·L-1) Platelet-rich plasma (PRP) was prepared from the blood of adult humans. CD62P was measured by flow cytometry following activation of PRP with ADP in the absence and presence of the selective antagonists of P2Y1 and P2Y12 receptors, MRS2500 and PSB0739 (both 0.155-10 µmol·L-1), respectively. Effects of the test agents on ADP-activated, CD62P-dependent formation of neutrophil:platelet (NP) aggregates were also measured by flow cytometry, while phosphatidylinositol 3-kinase (PI3K) activity was measured according to Akt1 phosphorylation in platelet lysates. Treatment with MRS2500 or PSB0739 at 10 µmol·L-1 almost completely attenuated (94.6% and 86% inhibition, respectively) ADP-activated expression of CD62P and also inhibited NP aggregate formation. To probe the mechanisms involved in P2Y1/P2Y12 receptor-mediated expression of CD62P, PRP was pre-treated with U73122 (phospholipase C (PLC) inhibitor), 2-aminoethoxy-diphenyl borate (2-APB, inositol triphosphate receptor antagonist), calmidazolium chloride (calmodulin inhibitor), or wortmannin (PI3K inhibitor). U73122, 2-APB, and wortmannin caused almost complete inhibition of ADP-activated expression of CD62P, while calmidazolium chloride caused statistically significant, partial inhibition. PSB0739, but not MRS2500, caused potent inhibition of PI3K-mediated phosphorylation of Akt1. Optimal mobilization of CD62P by ADP-stimulated platelets is critically dependent on the co-activation of platelet P2Y1 and P2Y12 receptors. P2Y12 receptor activation is the key event in activation of PI3K, while activation of the P2Y1 receptor appears to create a high cytosolic Ca2+ environment conducive to optimum PI3K activity.

13.
Pharmaceuticals (Basel) ; 13(11)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233675

RESUMO

Tumor cells are particularly adept at exploiting the immunosuppressive potential of neutrophils as a strategy to achieve uncontrolled proliferation and spread. Recruitment of neutrophils, particularly those of an immature phenotype, known as granulocytic myeloid-derived suppressor cells, is achieved via the production of tumor-derived granulocyte colony-stimulating factor (G-CSF) and neutrophil-selective chemokines. This is not the only mechanism by which G-CSF contributes to tumor-mediated immunosuppression. In this context, the G-CSF receptor is expressed on various cells of the adaptive and innate immune systems and is associated with induction of T cell polarization towards the Th2 and regulatory T cell (Treg) phenotypes. In contrast to the potentially adverse effects of sustained, endogenous production of G-CSF by tumor cells, stringently controlled prophylactic administration of recombinant (r) G-CSF is now a widely practiced strategy in medical oncology to prevent, and in some cases treat, chemotherapy-induced severe neutropenia. Following an overview of the synthesis, structure and function of G-CSF and its receptor, the remainder of this review is focused on: (i) effects of G-CSF on the cells of the adaptive and innate immune systems; (ii) mechanisms by which this cytokine promotes tumor progression and invasion; and (iii) current clinical applications and potential risks of the use of rG-CSF in medical oncology.

14.
Arch Environ Contam Toxicol ; 79(4): 508-523, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33074408

RESUMO

This study compared four different statistical methods, involving six estimation procedures, for addressing censored left data in measuring temporal trends of eight different pyrethroids measured in sediment from a 10-year data set in a residential California stream (Pleasant Grove Creek). The statistical methods used were: the Kaplan-Meier (km) method; the robust regression on order statistics (ros using normal and log normal distributions rosln); the maximum likelihood estimation (mlen using normal and log normal distributions mleln); and a substitution method (sub) using ½ the detection limit. For five of the eight pyrethroids (bifenthrin, cyfluthrin, cypermethrin, lambda-cyhalothrin, and permethrin), the six statistical methods generally agree, with one exception, that the data set exhibit significant declining trends. In the case of bifenthrin, the slight disagreement among statistical methods only occurred for the mleln estimate that did not show a significant declining trend, whereas the other five methods did. For deltamethrin, esfenvalerate, and fenpropathrin, all six statistical methods were in agreement showing no significant trends. Possible reasons for declining sediment concentrations of pyrethroids in Pleasant Grove Creek are urban label changes effective in 2012-2015 that reduced residential use, variable annual rainfall, and more responsible homeowner use based on outreach/education programs.


Assuntos
Monitoramento Ambiental/métodos , Inseticidas/análise , Piretrinas/análise , Poluentes Químicos da Água/análise , Animais , California , Nitrilas , Permetrina/análise , Rios
15.
Front Immunol ; 11: 577303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042161

RESUMO

Community-acquired pneumonia (CAP) remains an important cause of morbidity and mortality throughout the world with much recent and ongoing research focused on the occurrence of cardiovascular events (CVEs) during the infection, which are associated with adverse short-term and long-term survival. Much of the research directed at unraveling the pathogenesis of these events has been undertaken in the settings of experimental and clinical CAP caused by the dangerous, bacterial respiratory pathogen, Streptococcus pneumoniae (pneumococcus), which remains the most common bacterial cause of CAP. Studies of this type have revealed that although platelets play an important role in host defense against infection, there is also increasing recognition that hyperactivation of these cells contributes to a pro-inflammatory, prothrombotic systemic milieu that contributes to the etiology of CVEs. In the case of the pneumococcus, platelet-driven myocardial damage and dysfunction is exacerbated by the direct cardiotoxic actions of pneumolysin, a major pore-forming toxin of this pathogen, which also acts as potent activator of platelets. This review is focused on the role of platelets in host defense against infection, including pneumococcal infection in particular, and reviews the current literature describing the potential mechanisms by which platelet activation contributes to cardiovascular complications in CAP. This is preceded by an evaluation of the burden of pneumococcal infection in CAP, the clinical features and putative pathogenic mechanisms of the CVE, and concludes with an evaluation of the potential utility of the anti-platelet activity of macrolides and various adjunctive therapies.


Assuntos
Plaquetas/imunologia , Doenças Cardiovasculares/imunologia , Infecções Comunitárias Adquiridas/imunologia , Pneumonia Pneumocócica/imunologia , Streptococcus pneumoniae/fisiologia , Animais , Infecções Comunitárias Adquiridas/tratamento farmacológico , Proteína HMGB1/metabolismo , Humanos , Macrolídeos/uso terapêutico , Ativação Plaquetária , Pneumonia Pneumocócica/tratamento farmacológico
16.
Biomed Res Int ; 2020: 8237402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32923486

RESUMO

Materials and Methods: The planktonic and biofilm-forming cultures were prepared in Middlebrook 7H9 and Sauton broth media, respectively, using Mtb strain, H37Rv. The effects of CSC at concentrations of 0.05-3.12 mg/L on growth, biofilm formation and structure were evaluated using microplate Alamar Blue assay, spectrophotometric procedure and scanning electron microscopy (SEM), respectively. Involvement of reactive oxygen species in CSC-mediated biofilm formation was investigated by including catalase in biofilm-forming cultures. Results: CSC did not affect the growth of planktonic bacteria, but rather led to a statistically significant increase in biofilm formation at concentrations of 0.4-3.12 mg/L, as well as in the viability of biofilm-forming bacteria at CSC concentrations of 0.2-1.56 mg/L. SEM confirmed an agglomerated biofilm matrix and irregular bacterial morphology in CSC-treated biofilms. Inclusion of catalase caused significant attenuation of CSC-mediated augmentation of biofilm formation by Mtb, implying involvement of oxidative stress. These findings demonstrate that exposure of Mtb to CSC resulted in increased biofilm formation that appeared to be mediated, at least in part, by oxidative stress, while no effect on planktonic cultures was observed. Conclusion: Smoking-related augmentation of biofilm formation by Mtb may contribute to persistence of the pathogen, predisposing to disease reactivation and counteracting the efficacy of antimicrobial chemotherapy.


Assuntos
Biofilmes/efeitos dos fármacos , Fumar Cigarros/efeitos adversos , Mycobacterium tuberculosis/efeitos dos fármacos , Tabaco/efeitos adversos , Antibacterianos/farmacologia , Catalase/metabolismo , Meios de Cultura/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Plâncton/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
18.
Support Care Cancer ; 28(12): 6145-6157, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32880733

RESUMO

The immune checkpoints associated with the CTLA-4 and PD-1 pathways are critical modulators of immune activation. These pathways dampen the immune response by providing brakes on activated T cells, thereby ensuring more uniform and controlled immune reactions and avoiding immune hyper-responsiveness and autoimmunity. Cancer cells often exploit these regulatory controls through a variety of immune subversion mechanisms, which facilitate immune escape and tumor survival. Immune checkpoint inhibitors (ICI) effectively block negative regulatory signals, thereby augmenting immune attack and tumor killing. This process is a double-edged sword in which release of regulatory controls is felt to be responsible for both the therapeutic efficacy of ICI therapy and the driver of immune-related adverse events (IrAEs). These adverse immune reactions are common, typically low-grade and may affect virtually every organ system. In the early clinical trials, lung IrAEs were rarely described. However, with ever-expanding clinical applications and more complex ICI-containing regimens, lung events, in particular, pneumonitis, have become increasingly recognized. ICI-related lung injury is clinically distinct from other types of lung toxicity and may lead to death in advanced stage disease. Thus, knowledge regarding the key characteristics and optimal treatment of lung-IrAEs is critical to good outcomes. This review provides an overview of lung-IrAEs, including risk factors and epidemiology, as well as clinical, radiologic, and histopathologic features of ICI-related lung injury. Management principles for ICI-related lung injury, including current consensus on steroid refractory pneumonitis and the use of other immune modulating agents in this setting are also highlighted.


Assuntos
Fatores Imunológicos/efeitos adversos , Imunoterapia/efeitos adversos , Pneumopatias/induzido quimicamente , Pneumopatias/terapia , Neoplasias/terapia , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , História do Século XXI , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Fatores Imunológicos/uso terapêutico , Agências Internacionais/organização & administração , Agências Internacionais/normas , Pneumopatias/epidemiologia , Cuidados Paliativos/organização & administração , Cuidados Paliativos/normas , Medicina Paliativa/organização & administração , Medicina Paliativa/normas , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Índice de Gravidade de Doença , Sociedades Médicas/organização & administração , Sociedades Médicas/normas
19.
Lung Cancer Manag ; 9(3): LMT37, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32774468

RESUMO

Aim: We investigated the prognostic potential of pretherapy measurement of the neutrophil/lymphocyte ratio (NLR) in patients (n = 56) with non-small-cell lung cancer deemed suitable for treatment with nivolumab. Materials & methods: This was a multicenter, noninterventional, retrospective data analysis, involving five oncology centers. Results: Patients with prenivolumab NLR values of <5 and ≥5 had respective median overall survival (OS) values of 14.5 and 7.02 months (p = 0.0026). Patients with ≤2 and >2 metastatic sites had median OS values of 11.4 and 6.1 months, respectively (p = 0.0174). A Cox multiple regression model revealed baseline NLR ≥5 as the only variable significantly associated with decreased OS (p < 0.0447). Conclusion: Pretreatment elevated NLR values are associated with poor outcomes in patients with recurrent metastatic non-small-cell lung cancer treated with nivolumab.

20.
Support Care Cancer ; 28(12): 6111-6117, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32857220

RESUMO

Despite the success and ongoing promise of monoclonal antibody-targeted immune checkpoint inhibitor immunotherapy of advanced malignancies, in particular, antibodies directed against CTLA-4 and PD-1/PD-L1, the development of immune-related adverse events (irAEs) remains a constraint of this type of therapy. Although rarely fatal, the occurrence of irAEs may necessitate discontinuation of immunotherapy, as well as administration of corticosteroids or other immunosuppressive therapies that may not only compromise efficacy but also predispose for development of opportunistic infection. Clearly, retention of efficacy of immune checkpoint-targeted therapies with concurrent attenuation of immune-mediated toxicity represents a formidable challenge. In this context, the current brief review examines mechanistic relationships between these events, as well as recent insights into immunopathogenesis, and strategies which may contribute to resolving this issue. These sections are preceded by brief overviews of the discovery and functions of CTLA-4 and PD-1, as well as the chronology of the development of immunotherapeutic monoclonal antibodies which target these immune checkpoint inhibitors.


Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Imunoterapia/efeitos adversos , Neoplasias/terapia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/uso terapêutico , Oncologia/métodos , Oncologia/tendências , Neoplasias/epidemiologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia
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