The contrast agent 2,3,5-triiodobenzoic acid (TIBA) induces cell death in tumor cells through the generation of reactive oxygen species.

The 2,3,5-triiodobenzoic acid (TIBA) is an iodine contrast agent used for visualization of tissue in X-ray techniques. However, TIBA induces physiological complications like increase in oxygen reactive species (ROS), and consequently, contrast-induced nephropathies. TIBA's antitumor activity was demonstrated in lung cancer, but the subcellular mechanisms involving its activity in tumor cells are still unknown. Thus, the objective of this work was evaluate whether the anti-tumor activity of TIBA involves ROS increase, in tumor lines of non-small cell lung cancer (H460), chronic myeloid leukemia (K562), and its cytotoxicity in normal renal epithelial (VERO). The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay was used for evaluation of cell viability, the H2DCFDA (cell-permeant 2',7'-dichlorodihydrofluorescein diacetate) fluorescent probe to evaluate ROS induction, cell cycle analysis was performed using flow cytometry to measure cell death, and immunofluorescence with annexin/7-AAD (7-amino-actinomycin D), to assess the association of cell death with the ROS generation. TIBA decreases cell viability in a dose-dependent manner for the H460 and K562. However, VERO cells showed less response to the drug, with 70% viable cells after 72 h of treatment in the highest concentration of the drug. While the tumor cells with only 20% viable cells. Besides, tumor cells exhibited higher DNA fragmentation, compared to the renal line (VERO with 5% of fragmented DNA, H460 with 26%, and 56% in K562). Finally, TIBA-induced ROS increase and apoptosis in all lines, which is significantly decreased after treatment with the antioxidant N-acetyl-cysteine (NAC). These data demonstrate the relationship between the increased cellular oxidative stress and the anti-tumor action of the TIBA.

Immunoinformatics and analysis of antigen distribution of Ureaplasma diversum strains isolated from different Brazilian states.

BACKGROUND: Ureaplasma diversum has numerous virulence factors that contribute to pathogenesis in cattle, including Lipid-associated membrane proteins (LAMPs). Therefore, the objectives of this study were to evaluate in silico important characteristics for immunobiological applications and for heterologous expression of 36 LAMPs of U. diversum (UdLAMPs) and, also, to verify by conventional PCR the distribution of these antigens in strains of Brazilian states (Bahia, Minas Gerais, São Paulo, and Mato Grosso do Sul). The Manatee database was used to obtain the gene and peptide sequences of the antigens. Similarity and identity studies were performed using BLASTp and direct antigenicity was evaluated by the VaxiJen v2.0 server. Epitope prediction for B lymphocytes was performed on the BepiPred v2.0 and CBTOPE v1.0 servers. NetBoLApan v1.0 was used to predict CD8+ T lymphocyte epitopes. Subcellular location and presence of transmembrane regions were verified by the software PSORTb v3.0.2 and TMHMM v2.2 respectively. SignalP v5.0, SecretomeP v2.0, and DOLOP servers were used to predict the extracellular excretion signal. Physico-chemical properties were evaluated by the web-software ProtParam, Solpro, and Protein-sol. RESULTS: In silico analysis revealed that many UdLAMPs have desirable properties for immunobiological applications and heterologous expression. The proteins gudiv_61, gudiv_103, gudiv_517, and gudiv_681 were most promising. Strains from the 4 states were PCR positive for antigens predicted with immunogenic and/or with good characteristics for expression in a heterologous system. CONCLUSION: These works contribute to a better understanding of the immunobiological properties of the UdLAMPs and provide a profile of the distribution of these antigens in different Brazilian states.

Allantoin reduces cell death induced by cisplatin: possible implications for tumor lysis syndrome management.

Massive lysis of tumor mass in cancer patients under chemotherapy regimens generates high levels of uric acid, leading to what is known as tumor lysis syndrome (TLS). Rasburicase, a recombinant urate oxidase, converts urate to allantoin, which is readily excreted by the kidneys. Even though there is a high production of allantoin from urate in cancer patients following rasburicase treatment, there are no studies on how allantoin excess could interfere with chemotherapy. We have evaluated allantoin interference with cisplatin efficiency on the lung cancer cell line H460 in vitro. The cells were treated with cisplatin (33 µM), with or without allantoin, for 48 h, in the presence or absence of UV light, and N-acetyl-L-cysteine (NAC) for 24 h. Cell viability, cell cycle, ROS production, apoptosis and immunoblot assays were performed. We showed that allantoin reduced the apoptosis induced by cisplatin in the H460 cell line. However, the activity of carboplatin and oxaliplatin, betulinic acid, TIBA, UV and H2O2 was not affected by allantoin. NMR spectroscopy showed that allantoin reduces cisplatin activity through direct interaction with cisplatin.

Metformin as a therapeutic tool for resistant hematological malignancies: a literature review.

BACKGROUND AND OBJECTIVE: Hematological malignancies (HMs) are a group of neoplasms with hematopoietic origin, currently divided into leukemias, lymphomas and multiple myeloma (MM). Although the advances in the management of HMs, the rate of drug resistance, relapse and refractory disease has been increasing, requiring new therapeutic strategies. In this review, we aim to summarize metformin's antitumoral mechanisms of action and present the latest studies of metformin action in HMs, including in resistant ones. METHODS: For this review of literature, studies published between 1996 and 2023 from PubMed and clinical trials submitted to clinicaltrials.gov were considered. KEY CONTENT AND FINDINGS: Throughout this review we demonstrated the capacity of metformin to act as an anti-HMs drug, being able to re-sensitize HMs to classical anti-HMs agents and to overcome relapse and refractory HMs, as shown in vitro and in vivo studies. Associated with the potential anti-HM effect of metformin, some clinical trials are in progress, including in the view of reducing resistance and recurrence rate of HMs, which requires further exploration. The relationship among HMs cancer stem cells (HMs CSCs), drug resistance, cancer recurrence, and the effect of metformin in inhibiting CSCs were also discussed, despite this field needing more attention. CONCLUSIONS: In summary, metformin is a promising anti-HMs drug that can enhance patients' survival and prognosis through its action in the improvement of HMs response.

Virus-Induced Lysis of Tumor and Other Pathogenic Unicellular Entities and Its Potential to Treat Leishmaniasis.

This article is focused on the main pathways used by viruses to achieve infection and lysis of unicellular eukaryotes described as pathogenic for multicellular organisms. In light of the recent discussions on how tumor cells exhibit unicellular behavior, highly malignant cells can be considered as another unicellular pathogenic entity, but with endogenous origin. Thus, a comparative panel of viral lysis of exogenous pathogenic unicellular eukaryotes such as Acanthamoeba sp., yeast, and tumors is presented. The important intracellular parasite Leishmania sp is also presented, which, in contrast, has its virulence improved by viral infections. The possible exploitation of viral-mediated eukaryotic cell lysis to overcome infections of Leishmania sp is discussed.

Connexin Expression in Pituitary Adenomas and the Effects of Overexpression of Connexin 43 in Pituitary Tumor Cell Lines.

Gap junction intercellular communication (GJIC) is considered a key mechanism in the regulation of tissue homeostasis. GJIC structures are organized in two transmembrane channels, with each channel formed by connexins (Cxs). GJIC and Cxs expression alterations are related to the process of tumorigenesis in different cell types. Pituitary neuroendocrine tumors (PitNETs) represent 15-20% of intracranial neoplasms, and usually display benign behavior. Nevertheless, some may have aggressive behavior, invading adjacent tissues, and featuring a high proliferation rate. We aimed to assess the expression and relevance of GJIC and Cxs proteins in PitNETs. We evaluated the mRNA expression levels of Cx26, 32, and 43, and the protein expression of Cx43 in a series of PitNETs. In addition, we overexpressed Cx43 in pituitary tumor cell lines. At the mRNA level, we observed variable expression of all the connexins in the tumor samples. Cx43 protein expression was absent in most of the pituitary tumor samples that were studied. Moreover, in vitro studies revealed that the overexpression of Cx43 decreases cell growth and induces apoptosis in pituitary tumor cell lines. Our results indicate that the downregulation of Cx43 protein might be involved in the tumorigenesis of most pituitary adenomas and have a potential therapeutic value for pituitary tumor therapy.

Heterologous Expression, Purification, and Immunomodulatory Effects of Recombinant Lipoprotein GUDIV-103 Isolated from Ureaplasma diversum.

Ureaplasma diversum is a bacterial pathogen that infects cattle and can cause severe inflammation of the genital and reproductive systems. Lipid-associated membrane proteins (LAMPs), including GUDIV-103, are the main virulence factors in this bacterium. In this study, we heterologously expressed recombinant GUDIV-103 (rGUDIV-103) in Escherichia coli, purified it, and evaluated its immunological reactivity and immunomodulatory effects in bovine peripheral blood mononuclear cells (PBMCs). Samples from rabbits inoculated with purified rGUDIV-103 were analysed using indirect enzyme-linked immunosorbent assay and dot blotting to confirm polyclonal antibody production and assess kinetics, respectively. The expression of this lipoprotein in field isolates was confirmed via Western blotting with anti-rGUDIV-103 serum and hydrophobic or hydrophilic proteins from 42 U. diversum strains. Moreover, the antibodies produced against the U. diversum ATCC 49783 strain recognised rGUDIV-103. The mitogenic potential of rGUDIV-103 was evaluated using a lymphoproliferation assay in 5(6)-carboxyfluorescein diacetate succinimidyl ester−labelled bovine PBMCs, where it induced lymphocyte proliferation. Quantitative polymerase chain reaction analysis revealed that the expression of interleukin-1ß, toll-like receptor (TLR)-α, TLR2, TLR4, inducible nitric oxide synthase, and caspase-3−encoding genes increased more in rGUDIV-103−treated PBMCs than in untreated cells (p < 0.05). Treating PBMCs with rGUDIV-103 increased nitric oxide and hydrogen peroxide levels. The antigenic and immunogenic properties of rGUDIV-103 suggested its suitability for immunobiological application.

Imbalanced circulating matrix metalloproteinases in polycystic ovary syndrome.

Altered levels of matrix metalloproteinases (MMPs) may reflect relevant pathogenetic mechanisms of disease conditions. The objective of this study was to compare the plasma levels of MMPs and tissue inhibitors of MMPs (TIMPs) in polycystic ovary syndrome (PCOS) patients with those found in healthy ovulatory controls and to examine whether the levels of these biomarkers are associated with clinical and biochemical features of this syndrome. Sixty-five healthy ovulatory subjects (controls) and 80 patients with PCOS were include in this study. MMP-2, MMP-8, MMP-9, TIMP-1, TIMP-2 concentrations were measured in plasma samples by gelatin zymography or enzyme-linked immunoassays. MMP-2, MMP-8, MMP-9, and TIMP-1 levels were similar in PCOS patients and in healthy controls (P > 0.05). PCOS patients had lower plasma TIMP-2 levels than healthy controls (P < 0.05). We found higher MMP-2/TIMP-2 and MMP-9/TIMP-1 ratios in PCOS patients than in healthy controls (all P < 0.05). Testosterone levels correlated positively with the MMP-9/TIMP-1 ratio and negatively with TIMP-2 levels (r = 0.26, P < 0.01 and r = -0.21, P = 0.02, respectively). In addition, only testosterone was an independent predictor of TIMP-2 levels (estimate = -0.35, P = 0.04) and the MMP-9/TIMP-1 ratio (estimate = 0.01, P = 0.04). We found evidence indicating that the balance between MMPs and TIMPs in women with PCOS is altered, probably due to androgen excess found in these women.

Pomolic acid may overcome multidrug resistance mediated by overexpression of anti-apoptotic Bcl-2 proteins.

Multidrug resistance (MDR) is multifactorial and may be mediated by overexpression of anti-apoptotic proteins. This paper investigated whether pomolic acid (PA) was able to overcome resistance mediated by overexpression of Bcl-2 or BcL-xL. The results obtained showed that overexpression of these proteins partially inhibited the PA-induced apoptosis, loss of mitochondrial membrane potential and caspase -3 and -9 activation observed in HL-60/neo. Since Bcl-2 transfected cell lines were shown to be quite resistant to a series of chemotherapeutic agents, the data presented call attention to the possible clinical significance of PA as an anti-MDR drug.

Assessment of neuromuscular electrical stimulation in critically ill patients: physical therapists' knowledge and barriers to its use / Avaliação do uso da estimulação elétrica neuromuscular em pacientes críticos: conhecimento dos fisioterapeutas e barreiras à implementação / Evaluación del uso de la electroestimulación neuromuscular en pacientes críticos: conocimiento de los fisioterapeutas y barreras para su implementación

ABSTRACT Transcutaneous neuromuscular electrical stimulation (NMES) is considered an important tool to prevent muscle mass and strength loss in patients admitted to intensive care units (ICU). This study aimed to evaluate physical therapists' profile and knowledge of NMES and identify the main barriers to its use in ICUs. This observational cross-sectional study was conducted via a structured questionnaire created by the authors. It consisted of 12 objective questions to analyze physical therapists' knowledge of NMES use in critically ill patients. Physical therapists were invited to participate in this study during an international symposium on NMES. In total, 56 physical therapists, with a mean age of 33.5±7.2 years and working an average of 9.7±7 years after graduation, completed the survey. Overall, 34 respondents worked in ICUs, of which only four (12%) reported regular NMES use in their ICUs. We found a low average of correct answers to our questionnaire (25%; 3/12). The main barriers reported to using NMES in ICUs were lack of knowledge (28; 50%) and equipment (24; 43%). The number of correct answers expert and non-expert physical therapists was not statistically significant (p=0.68). Thus, we observed participants' poor knowledge of NMES use in critically ill patients. Respondents showed that NMES has been underused in their ICUs. Lack of knowledge and equipment seems to be the main barriers for the use of NMES in ICUs.

RESUMO A estimulação elétrica neuromuscular transcutânea (EENM) é considerada uma importante ferramenta para prevenir a perda de força e massa muscular em pacientes internados em unidades de terapia intensiva (UTIs). Este estudo teve como objetivo avaliar o perfil e conhecimento dos fisioterapeutas sobre a EENM e identificar as principais barreiras para sua utilização na UTI. Foi realizado um estudo observacional transversal, por meio de um questionário estruturado elaborado pelos autores. O questionário foi composto por 12 questões objetivas que visavam analisar o nível de conhecimento dos fisioterapeutas sobre o uso da EENM em pacientes críticos. Os fisioterapeutas foram convidados a participar do estudo durante um simpósio internacional sobre EENM. Cinquenta e seis fisioterapeutas completaram a pesquisa, a média de idade foi de 33,5±7,2 anos e o tempo médio de graduação de 9,7±7 anos. Trinta e quatro entrevistados trabalhavam na UTI, e destes apenas 4 (12%) relataram que a EENM era realizada rotineiramente em suas UTIs. Observou-se baixo nível de conhecimento sobre o uso da EENM em pacientes críticos no questionário, com média de 25% de acertos (3/12). Ao comparar os fisioterapeutas especialistas e não especialistas, o número de acertos não foi estatisticamente significativo (p=0,68). As principais barreiras relatadas para a utilização da técnica foram a falta de conhecimento 28 (50%) e a falta de equipamentos 24 (43%). Os entrevistados demonstraram que a EENM tem sido subutilizada em suas UTIs.

RESUMEN La electroestimulación neuromuscular transcutánea (TENS) es una herramienta importante para prevenir la pérdida de fuerza y masa muscular en pacientes ingresados en unidades de cuidados intensivos (UCI). Este estudio tuvo como objetivo evaluar el perfil y el conocimiento de los fisioterapeutas sobre la TENS, así como identificar las principales barreras para su uso en la UCI. Se llevó a cabo un estudio observacional transversal mediante un cuestionario estructurado desarrollado por los autores. El cuestionario constaba de 12 preguntas objetivas cuyo objetivo era analizar el nivel de conocimiento de los fisioterapeutas sobre el uso de la TENS en pacientes críticos. Se invitó a los fisioterapeutas a participar en el estudio durante un simposio internacional sobre TENS. Cincuenta y seis fisioterapeutas completaron la encuesta, la edad media fue de 33,5±7,2 años, y el tiempo medio desde la graduación fue de 9,7±7 años. Treinta y cuatro encuestados trabajaban en la UCI, y de estos solo 4 (12%) informaron que la TENS se realizaba de forma rutinaria en las UCI donde trabajaban. Los resultados del cuestionario mostraron un bajo nivel de conocimiento sobre el uso de la TENS en pacientes críticos, con un promedio de 25% de respuestas correctas (3/12). En la comparación entre los fisioterapeutas especialistas y los no especialistas, el número de respuestas correctas no fue estadísticamente significativo (p=0,68). Las principales barreras reportadas para el uso de esta técnica fueron la falta de conocimiento 28 (50%) y la falta de equipamiento 24 (43%). Los encuestados demostraron que esta técnica es infrautilizada en las UCI.

Oncogenes: The Passport for Viral Oncolysis Through PKR Inhibition.

The transforming properties of oncogenes are derived from gain-of-function mutations, shifting cell signaling from highly regulated homeostatic to an uncontrolled oncogenic state, with the contribution of the inactivating mutations in tumor suppressor genes P53 and RB, leading to tumor resistance to conventional and target-directed therapy. On the other hand, this scenario fulfills two requirements for oncolytic virus infection in tumor cells: inactivation of tumor suppressors and presence of oncoproteins, also the requirements to engage malignancy. Several of these oncogenes have a negative impact on the main interferon antiviral defense, the double-stranded RNA-activated protein kinase (PKR), which helps viruses to spontaneously target tumor cells instead of normal cells. This review is focused on the negative impact of overexpression of oncogenes on conventional and targeted therapy and their positive impact on viral oncolysis due to their ability to inhibit PKR-induced translation blockage, allowing virion release and cell death.

Pomolic acid triggers mitochondria-dependent apoptotic cell death in leukemia cell line.

One of the major goals in chemotherapy is to circumvent anti-apoptotic strategies developed by tumor cells. In a previous paper, we showed that pomolic acid (PA) is able to kill the leukemia cell line K562 and its MDR derivative, Lucena 1. Here, we demonstrated that PA-induced apoptosis of HL-60 cells is dependent on the activation of caspases-3 and -9 and dissipation of the mitochondrial transmembrane potential (Deltapsim). Disruption of Deltapsim precedes caspase activation and is not inhibited by zVAD-fmk indicating mitochondria as the main target of PA. Our data pointed to the potential use of PA to overcome apoptosis resistance.

Perillyl alcohol induces apoptosis in human glioblastoma multiforme cells.

Standard treatment of glioblastoma multiforme consisting of surgical resection, radiation and/or chemotherapy is rarely curative, emphasizing the need for new chemotherapeutic drugs. The monoterpene perillyl alcohol (POH) has preventive and therapeutic effects in a wide variety of pre-clinical tumor models and is currently under phase I and II clinical trials. In the present study, we analyzed its effect on human glioblastoma cell lines (U87 and A172) and a primary cell culture derived from a human glioblastoma tumor specimen (GBM-1). Using MTT, we showed that POH inhibits the viability of glioblastomas in a concentration-dependent way. Glioblastoma cell lines treated with POH showed morphological alterations characteristic of apoptosis. Analysis of cell cycle and quantification of DNA fragmentation, in cells stained with propidium iodide (PI), confirmed the apoptotic effect of POH on glioblastomas. These data support the potential usefulness of perillyl alcohol as an effective chemotherapeutic agent for patients with recurrent glioblastoma multiforme.

The study of homology between tumor progression genes and members of retroviridae as a tool to predict target-directed therapy failure.

Oncogenes are the primary candidates for target-directed therapy, given that they are involved directly in the progression and resistance of tumors. However, the appearance of point mutations can hinder the treatment of patients with these new molecules, raising costs and the need to development new analogs that target the novel mutations. Based on an analysis of homologies, the present study discusses the possibility of predicting the failure of a protein as a pharmacological target, due to its similarities with retrovirus sequences, which have extremely high mutation rates. This analysis was based on the molecular evidence available in the literature, and widely-used and well-established PSI-BLAST, with two iterations and maximum of 500 aligned sequences. The possibility of predicting which newly-discovered genes involved in tumor progression would likely result in the failure of targeted therapy, using free, simple and automated bioinformatics tools, could provide substantial savings in the time and financial resources needed for long-term drug development.

Convivência virtual: a arte de tecer redes com o trabalho afetivo antimanicomial / Virtual conviviality: the art of weaving networks with affective anti-asylum work

Este artigo visa compartilhar a experiência de trabalho do Centro de Convivência e Cultura da Zona Oeste da cidade do Rio de Janeiro, problematizando o conceito de trabalho afetivo antimanicomial, antes e durante a pandemia de Covid-19. Apresenta-se uma pesquisa com os trabalhadores destes serviços sobre a atividade de convivência e como se opera a dimensão afetiva, usando o método da oficina de fotos. Narra-se a construção de oficinas virtuais, decorrentes do contexto pandêmico, que inventaram outros modos de fortalecer redes de afeto e reduzir os danos do isolamento social através de tecnologias da informação e comunicação.

Pentacyclic triterpenes from Chrysobalanaceae species: cytotoxicity on multidrug resistant and sensitive leukemia cell lines.

Plants are known as important source in the search for new anti-cancer agents. Cytotoxicity-guided fractionation of leaves and fruits from Licania tomentosa Bench and leaves from Chrysobalanus icaco L. resulted in the isolation of betulinic, oleanolic and pomolic acids. These triterpenoids inhibited the growth and induced apoptosis of K562, an erythroleukemia cell line. Most importantly, they also inhibited the proliferation of Lucena 1, a vincristine-resistant derivative of K562 that displays several multidrug resistance (MDR) characteristics. Taken together, our findings emphasize the anti-tumor activity of these triterpenes on leukemia cell lines and call attention to their potential as anti MDR agents.