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1.
bioRxiv ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38948812

RESUMO

Solid carcinomas are often highly heterogenous cancers, arising from multiple epithelial cells of origin. Yet, how the cell of origin influences the response of the tumor microenvironment is poorly understood. Lung adenocarcinoma (LUAD) arises in the distal alveolar epithelium which is populated primarily by alveolar epithelial type I (AT1) and type II (AT2) cells. It has been previously reported that Gramd2 + AT1 cells can give rise to a histologically-defined LUAD that is distinct in pathology and transcriptomic identity from that arising from Sftpc + AT2 cells 1,2 . To determine how cells of origin influence the tumor immune microenvironment (TIME) landscape, we comprehensively characterized transcriptomic, molecular, and cellular states within the TIME of Gramd2 + AT1 and Sftpc + AT2-derived LUAD using KRAS G12D oncogenic driver mouse models. Myeloid cells within the Gramd2 + AT1-derived LUAD TIME were increased, specifically, immunoreactive monocytes and tumor associated macrophages (TAMs). In contrast, the Sftpc + AT2 LUAD TIME was enriched for Arginase-1 + myeloid derived suppressor cells (MDSC) and TAMs expressing profiles suggestive of immunosuppressive function. Validation of immune infiltration was performed using flow cytometry, and intercellular interaction analysis between the cells of origin and major myeloid cell populations indicated that cell-type specific markers SFTPD in AT2 cells and CAV1 in AT1 cells mediated unique interactions with myeloid cells of the differential immunosuppressive states within each cell of origin mouse model. Taken together, Gramd2 + AT1-derived LUAD presents with an anti-tumor, immunoreactive TIME, while the TIME of Sftpc + AT2-derived LUAD has hallmarks of immunosuppression. This study suggests that LUAD cell of origin influences the composition and suppression status of the TIME landscape and may hold critical implications for patient response to immunotherapy.

2.
Ann Bot ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850278

RESUMO

BACKGROUND AND AIMS: Climate change is a global phenomenon species are experiencing, which in arid regions will translate into more frequent and intense drought. The Sonoran Desert is becoming hotter and drier, and many organisms are rapidly changing in abundance and distribution. These population attributes directly depend on the dynamics of the population, which in turn depends on the vital rates of its individuals; yet few studies have documented the effects of climate change on the population dynamics of keystone species such as the saguaro cactus (Carnegiea gigantea). Although saguaros have traits that enable them to withstand present environmental conditions, climate change could make them vulnerable if forced beyond their tolerance limits. METHODS: We evaluated the effect of climate change on 13 saguaro populations spanning most of the species' distribution range. Using field data from 2014 to 2016, we built an integral projection model (IPM) describing the environmentally-explicit dynamics of the populations. We used this IPM, along with projections of two climate change and one no-change scenarios, to predict population sizes (N) and growth rates (λ) from 2017 to 2099 and compared these scenarios to demonstrate the effect of climate change on saguaro's future. KEY RESULTS: We found that all populations will decline, mainly due to future increases in drought, mostly hindering recruitment. However, the decline will be differential across populations, since those located near the coast will be affected by harsher drought events than those located further inland. CONCLUSIONS: Our study demonstrates that climate change and its associated increase in drought pose a significant threat to the saguaro cactus populations in the Sonoran Desert. Our findings indicate that the recruitment of saguaros, vital for establishing new individuals, is particularly vulnerable to intensifying drought conditions. Importantly, regional climate trends will have different impacts on saguaro populations across their distribution range.

3.
Clin Exp Metastasis ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717519

RESUMO

Metastatic disease results from the dissemination of tumor cells beyond their organ of origin to grow in distant organs and is the primary cause of death in patients with advanced breast cancer. Preclinical murine models in which primary tumors spontaneously metastasize are valuable tools for studying metastatic progression and novel cancer treatment combinations. Here, we characterize a novel syngeneic murine breast tumor cell line that provides a model of spontaneously metastatic neu-expressing breast cancer with quicker onset of widespread metastases after orthotopic mammary implantation in immune-competent NeuN mice. The NT2.5-lung metastasis (-LM) cell line was derived from serial passaging of tumor cells that were macro-dissected from spontaneous lung metastases after orthotopic mammary implantation of parental NT2.5 cells. Within one week of NT2.5-LM implantation, metastases are observed in the lungs. Within four weeks, metastases are also observed in the bones, spleen, colon, and liver. We demonstrate that NT2.5-LM metastases are positive for NeuN-the murine equivalent of human epidermal growth factor 2 (HER2). We further demonstrate altered expression of markers of epithelial-to-mesenchymal transition (EMT), suggestive of their enhanced metastatic potential. Genomic analyses support these findings and reveal enrichment in EMT-regulating pathways. In addition, the metastases are rapidly growing, proliferative, and responsive to HER2-directed therapy. The new NT2.5-LM model provides certain advantages over the parental NT2/NT2.5 model, given its more rapid and spontaneous development of metastases. Besides investigating mechanisms of metastatic progression, this new model may be used for the rationalized development of novel therapeutic interventions and assessment of therapeutic responses.

4.
Breast Cancer Res Treat ; 206(2): 245-259, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38643348

RESUMO

PURPOSE: Programmed death receptor ligand-1 (PD-L1) expression and tumor mutational burden (TMB) are approved screening biomarkers for immune checkpoint inhibition (ICI) in advanced triple negative breast cancer. We examined these biomarkers along with characterization of the tumor microenvironment (TME) between breast tumors (BrTs), axillary metastases (AxMs), liver metastases (LvMs), non-axillary lymph node metastases, and non-liver metastases to determine differences related to site of metastatic disease. METHODS: 3076 unpaired biopsies from breast cancer patients were analyzed using whole transcriptome sequencing and NextGen DNA depicting TMB within tumor sites. The PD-L1 positivity was determined with VENTANA PD-L1 (SP142) assay. The immune cell fraction within the TME was calculated by QuantiSeq and MCP-counter. RESULTS: Compared to BrT, more LvM samples had a high TMB (≥ 10 mutations/Mb) and fewer LvM samples had PD-L1+ expression. Evaluation of the TME revealed that LvM sites harbored lower infiltration of adaptive immune cells, such as CD4+, CD8+, and regulatory T-cells compared with the BrT foci. We saw differences in innate immune cell infiltration in LvM compared to BrT, including neutrophils and NK cells. CONCLUSIONS: LvMs are less likely to express PD-L1+ tumor cells but more likely to harbor high TMB as compared to BrTs. Unlike AxMs, LvMs represent a more immunosuppressed TME and demonstrate lower gene expression associated with adaptive immunity compared to BrTs. These findings suggest biopsy site be considered when interpreting results that influence ICI use for treatment and further investigation of immune composition and biomarkers expression by metastatic site.


Assuntos
Antígeno B7-H1 , Biomarcadores Tumorais , Neoplasias da Mama , Neoplasias Hepáticas , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Feminino , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Mutação , Metástase Linfática , Pessoa de Meia-Idade , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo
5.
J Med Food ; 27(4): 379-384, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38507677

RESUMO

Mushrooms of the genus Pleurotus have shown nematophagous activity as it produces many chemical compounds and enzymes affecting parasitic nematodes. This study aimed to extract the inhibitory activity of the five strains of the fungus Pleurotus spp. It was evaluated against eggs and larvae of Haemonchus contortus. The extract of P. ostreatus obtained the highest level of inhibition of eggs at 97.6% (1341 µg/mL) followed by P. pulmonarius (EPP) at 81.2% (774 µg/mL). The extract selected for evaluation against larvae was P. pulmonarius, showing no effect for L3 larvae, but for L4 larvae an immobility effect of 56.93% was observed at 900 µg/mL. The protein profile showed the presence of 23 protein bands in the extract. The crude extract of P. pulmonarius showed degradation of tissues both inside the eggs and larvae L1. Metabolites produced by Pleurotus mushrooms can consider using in agriculture sustainable by utilizing in producing of ovicidal and larvicidal against H. contortus instead of chemical compounds.


Assuntos
Agaricales , Haemonchus , Pleurotus , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Larva
6.
Diseases ; 12(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38534973

RESUMO

Meningitis is an inflammatory condition affecting the meninges surrounding the brain and spinal cord. Meningitis can be triggered by various factors, including infectious agents like viruses and bacteria and non-infectious contributors such as cancer or head injuries. The impact of meningitis on the central nervous system involves disruptions in the blood-brain barrier, cellular infiltrations, and structural alterations. The clinical features that differentiate between tuberculous meningitis (TBM) and non-tuberculous meningitis (NTM) are discussed in this review and aid in accurate diagnosis. The intricate interplay of reactive oxygen species, ferroptosis, and reactive nitrogen species within the central nervous system reveals a promising field of research for innovative therapeutic strategies tailored to TBM. This review highlights the alternative treatments targeting oxidative stress-induced TBM and ferroptosis, providing potential avenues for intervention in the pathogenesis of this complex condition.

7.
Biomedicines ; 12(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38540171

RESUMO

This review explores ferroptosis, a form of regulated cell death reliant on iron-induced phospholipid peroxidation, in diverse physiological and pathological contexts, including neurodegenerative disorders, and ischemia-reperfusion. In the realm of cardiovascular diseases, it significantly contributes to cardiomyopathies, including dilated cardiomyopathy, hypertrophic cardiomyopathy, and restrictive cardiomyopathy. Ferroptosis involves intricate interactions within cellular iron metabolism, lipid peroxidation, and the balance between polyunsaturated and monounsaturated fatty acids. Molecularly, factors like p53 and NRF2 impact cellular susceptibility to ferroptosis under oxidative stress. Understanding ferroptosis is vital in cardiomyopathies, where cardiac myocytes heavily depend on aerobic respiration, with iron playing a pivotal role. Dysregulation of the antioxidant enzyme GPX4 is linked to cardiomyopathies, emphasizing its significance. Ferroptosis's role in myocardial ischemia-reperfusion injury, exacerbated in diabetes, underscores its relevance in cardiovascular conditions. This review explores the connection between ferroptosis, the NRF2 pathway, and atherosclerosis, emphasizing their roles in protecting cells from oxidative stress and maintaining iron balance. It discusses the use of iron chelating agents in managing iron overload conditions, with associated benefits and challenges. Finally, it highlights the importance of exploring therapeutic strategies that enhance the glutathione (GSH) system and the potential of natural compounds like quercetin, terpenoids, and phenolic acids in reducing oxidative stress.

8.
bioRxiv ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38352476

RESUMO

Preclinical murine models in which primary tumors spontaneously metastasize to distant organs are valuable tools to study metastatic progression and novel cancer treatment combinations. Here, we characterize a novel syngeneic murine breast tumor cell line, NT2.5-lung metastasis (-LM), that provides a model of spontaneously metastatic neu-expressing breast cancer with quicker onset of widespread metastases after orthotopic mammary implantation in immune-competent NeuN mice. Within one week of orthotopic implantation of NT2.5-LM in NeuN mice, distant metastases can be observed in the lungs. Within four weeks, metastases are also observed in the bones, spleen, colon, and liver. Metastases are rapidly growing, proliferative, and responsive to HER2-directed therapy. We demonstrate altered expression of markers of epithelial-to-mesenchymal transition (EMT) and enrichment in EMT-regulating pathways, suggestive of their enhanced metastatic potential. The new NT2.5-LM model provides more rapid and spontaneous development of widespread metastases. Besides investigating mechanisms of metastatic progression, this new model may be used for the rationalized development of novel therapeutic interventions and assessment of therapeutic responses targeting distant visceral metastases.

9.
Toxins (Basel) ; 15(11)2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999486

RESUMO

GroEL is a chaperonin that helps other proteins fold correctly. However, alternative activities, such as acting as an insect toxin, have also been discovered. This work evaluates the chaperonin and insecticidal activity of different GroEL proteins from entomopathogenic nematodes on G. mellonella. The ability to synergize with the ExoA toxin of Pseudomonas aeruginosa was also investigated. The GroELXn protein showed the highest insecticidal activity among the different GroELs. In addition, it was able to significantly activate the phenoloxidase system of the target insects. This could tell us about the mechanism by which it exerts its toxicity on insects. GroEL proteins can enhance the toxic activity of the ExoA toxin, which could be related to its chaperonin activity. However, there is a significant difference in the synergistic effect that is more related to its alternative activity as an insecticidal toxin.


Assuntos
Inseticidas , Mariposas , Nematoides , Animais , Inseticidas/toxicidade , Inseticidas/metabolismo , Chaperonina 60/metabolismo , Chaperonina 60/farmacologia , Insetos/metabolismo , Bactérias/metabolismo , Larva/metabolismo
10.
Viruses ; 15(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38005901

RESUMO

Porcine circovirus type 3 (PCV3) is a nonenveloped virus of the Circoviridae family. This virus has been identified in pigs of different ages and pigs with several clinical manifestations of the disease or even in apparently healthy pigs. While PCV3 was first reported in 2015, several retrospective studies have reported the virus before that year. The earliest report indicates that PCV3 has been circulated in swine farms since 1996. In this study, we evaluated the presence of PCV3 in samples collected in Mexico in 2008, 2015, 2020, and 2021. This study assessed PCV3 DNA by qPCR and antibodies against CAP protein by indirect ELISA. The results showed that PCV3 (DNA and anti-CAP antibodies) was detected in the samples collected from 2008 to 2021. The highest prevalence was in 2008 (100%), and the lowest was in 2015 (negative). Genetic analysis of ORF2 showed that the virus identified belonged to genotype a, as most of the viruses identified thus far. PCV3 was detected in samples from piglets with respiratory signs and growth retardation, sows with reproductive failure, or asymptomatic piglets and sows. Pigs with respiratory signs, growth retardation, or reproductive failure had a higher prevalence of antibodies and qPCR-positive samples. In conclusion, this study showed that PCV3 has been circulating in Mexico since 2008 and that PCV3 DNA and antibodies were more prevalent in samples from pigs with clinical manifestations of diseases.


Assuntos
Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Animais , Suínos , Feminino , Estudos Retrospectivos , Doenças dos Suínos/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Circovirus/genética , México/epidemiologia , Anticorpos , DNA , Transtornos do Crescimento , Filogenia
11.
Animals (Basel) ; 13(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37889680

RESUMO

Microsporidia are unicellular eukaryotic obligate intracellular parasites with a wide range of hosts reported worldwide; however, little is known about the epidemiological data on microsporidia infection in animals from the Canary Islands. Since data on microsporidia infection in hedgehog species are scarce, the aim of this study was to analyze the presence and identity of microsporidia in a group of North African hedgehogs (Atelerix algirus) using microscopic and molecular methods. From December 2020 to September 2021, a total of 36 fecal samples were collected from naturally deceased hedgehogs from Tenerife and Gran Canaria. All samples showed spore-compatible structures (100%; 36/36) under microscopic analysis, of which 61.1% (22/36) were amplified via the nested-polymerase chain reaction (PCR) targeting the partial sequence of the 16S rRNA gene, the internal transcribed spacer (ITS) region, and the partial sequence of the 5.8S rRNA gene. After Sanger sequencing and ITS analysis, Enterocytozoon bieneusi was detected in 47.2% (17/36) of the samples, identifying two novel genotypes (AAE1 and AAE2), followed by the detection of an undetermined species in 8.3% (3/36) and Encephalitozoon cuniculi genotype I in 5.6% (2/36) of the samples. This study constitutes the first report of microsporidia species in Atelerix algirus worldwide, highlighting the high prevalence of zoonotic species.

12.
Animals (Basel) ; 13(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37443966

RESUMO

Lungworms are a major cause of feline respiratory disease, frequently underdiagnosed due to its presentation of symptoms being similar to that of other feline respiratory pathologies. Epidemiological data about these nematodes are scarce in the Canary Islands (Spain). Given the veterinary importance of these parasites, the aim of the present study was to improve the current epidemiological knowledge of the lungworm species that could be affecting feral cats in this archipelago. A total of 29 feral cats from La Gomera were analyzed. The respiratory tract of each animal was inspected and the nematodes obtained were identified by morphological keys and molecular techniques. Metastrongylids were detected to be widely distributed throughout the island with a prevalence of 55.2% (16/29). The species Aelurostrongylus abstrusus, Troglostrongylus brevior, Oslerus rostratus and Angiostrongylus chabaudi were identified. Also, coinfections with A. chabaudi and O. rostratus were detected in two animals. The present study shows a high diversity of lungworms in feral cats in La Gomera, with the first report of A. chabaudi and T. brevior for the Canary Archipelago and the first citation of A. chabaudi in cats for Spain. The wide distribution and high prevalence found in this study indicate a high risk of exposure to pulmonary infections in cats.

13.
Plants (Basel) ; 12(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447074

RESUMO

Mexico harbors over 50% of maize's genetic diversity in the Americas. Native maize varieties are actively managed by small-scale producers within a diverse array of cultivation systems. Seed lot use, exchange and admixture has consequences for the in situ conservation of such varieties. Here we analyze native maize seed management dynamics from 906 small-scale producers surveyed in three Mexican states: Mexico City, Oaxaca and Chiapas. Furthermore, we analyze how their management practices can relate to transgene presence, which was experimentally documented for maize samples associated with the applied surveys. Through a data mining approach, we investigated which practices might be related with a higher probability of transgene presence. The variables found to have a strong spatial association with transgene presence were: for Mexico City, maize producers with larger parcels; for Oaxaca, producer's age (43-46 years) and the sale of seed; for Chiapas, the use of agricultural machinery and younger producers (37-43 years). Additionally, transgene presence and frequency within the socioeconomic regions of Oaxaca and Chiapas was analyzed. In Oaxaca, higher transgene frequencies occurred in regions where transgene presence had been previously reported. In Chiapas, the border regions with Guatemala as well as a region where reproduction of improved seed takes place, the highest proportion of positive samples were found. A detailed mapping of regional seed markets and seed exchange sites together with deployment of national and local biosecurity measures, could help prevent the further spread of transgenes into native maize varieties, as well as improve conservation efforts.

14.
Animals (Basel) ; 13(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37370479

RESUMO

Angiostrongylus cantonensis is a metastrongyloid nematode and the etiologic agent of angiostrongyliasis, a disease characterized by eosinophilic meningitis. This emerging zoonotic parasite has undergone great expansion, including in some regions of Europe and America. In the Canary Islands, the parasite was first discovered parasitizing Rattus rattus on the island of Tenerife in 2010. To date, the distribution of this parasite in the Canary Islands has been restricted to the northern zone and the main cities of Tenerife. Using molecular tools for the sentinel species present in the Canary Islands, this study confirmed the presence of the nematode on two other islands in the Canary Archipelago: La Gomera and Gran Canaria. Furthermore, this emerging parasite was detected, besides in the common definitive host R. rattus, in wild Mus musculus and Felis catus and in four terrestrial gastropod species, Limacus flavus, Milax gagates, Insulivitrina emmersoni, and Insulivitrina oromii, two of them endemic to La Gomera, for the first time, increasing the number of non-definitive host species. This study reinforces the expansion character of A. cantonensis and highlights the importance of knowledge about sentinel species for identifying new transmission locations that help prevent and control the transmission of the parasite and, thus, prevent public health problems.

15.
Front Immunol ; 14: 1188815, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37359563

RESUMO

[This corrects the article DOI: 10.3389/fimmu.2023.1080238.].

16.
iScience ; 26(4): 106562, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37063467

RESUMO

This study reports the isolation and characterization of a human monoclonal antibody (mAb) called 19n01. This mAb was isolated by using single-cell RNAseq of B cells from donors infected with the ancestral strain. This mAb possesses a potent and broad capacity to bind and neutralize all previously circulating variants of concern (VOCs), including Omicron sublineages BA.1, BA.2, and BA.4/5. The pseudovirus neutralization assay revealed robust neutralization capacity against the G614 strain, BA.1, BA.2, and BA.4/5, with inhibitory concentration (IC50) values ranging from 0.0035 to 0.0164 µg/mL. The microneutralization assay using the G614 strain and VOCs demonstrated IC50 values of 0.013-0.267 µg/mL. Biophysical and structural analysis showed that 19n01 cross-competes with ACE2 binding to the receptor-binding domain (RBD) and the kinetic parameters confirmed the high affinity against the Omicron sublineages (KD of 61 and 30 nM for BA.2 and BA.4/5, respectively). These results suggest that the 19n01 is a remarkably potent and broadly reactive mAb.

17.
Cureus ; 15(2): e35283, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36968859

RESUMO

Sepsis is a major cause of mortality as a life-threatening condition that arises when the body's response to an infection injures its own tissue, and in the past decade, emphasis has been placed on early treatment to decrease mortality. In this case, we discuss the presentation of a young patient with sepsis due to acute complicated pyelonephritis with an obstructing ureterocele diagnosed by point-of-care ultrasound and explore the use of point-of-care ultrasound in sepsis.

18.
Front Immunol ; 14: 1080238, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969203

RESUMO

Advances in antigen targeting in veterinary medicine have gained traction over the years as an alternative approach for diseases that remain a challenge for traditional vaccines. In addition to the nature of the immunogen, antigen-targeting success relies heavily on the chosen receptor for its direct influence on the elicited response that will ensue after antigen uptake. Different approaches using antibodies, natural or synthetic ligands, fused proteins, and DNA vaccines have been explored in various veterinary species, with pigs, cattle, sheep, and poultry as the most frequent models. Antigen-presenting cells can be targeted using a generic approach, such as broadly expressed receptors such as MHC-II, CD80/86, CD40, CD83, etc., or focused on specific cell populations such as dendritic cells or macrophages (Langerin, DC-SIGN, XCR1, DC peptides, sialoadhesin, mannose receptors, etc.) with contrasting results. Interestingly, DC peptides show high specificity to DCs, boosting activation, stimulating cellular and humoral responses, and a higher rate of clinical protection. Likewise, MHC-II targeting shows consistent results in enhancing both immune responses; an example of this strategy of targeting is the approved vaccine against the bovine viral diarrhea virus in South America. This significant milestone opens the door to continuing efforts toward antigen-targeting vaccines to benefit animal health. This review discusses the recent advances in antigen targeting to antigen-presenting cells in veterinary medicine, with a special interest in pigs, sheep, cattle, poultry, and dogs.


Assuntos
Antígenos , Células Dendríticas , Bovinos , Animais , Suínos , Ovinos , Cães , Peptídeos , Macrófagos , Imunidade
19.
ACS Chem Biol ; 18(3): 629-642, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36854145

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant (MDR) bacterial pathogen of acute clinical significance. Resistance to current standard-of-care antibiotics, such as vancomycin and linezolid, among nosocomial and community-acquired MRSA clinical isolates is on the rise. This threat to global public health highlights the need to develop new antibiotics for the treatment of MRSA infections. Here, we describe a new benzamide FtsZ inhibitor (TXH9179) with superior antistaphylococcal activity relative to earlier-generation benzamides like PC190723 and TXA707. TXH9179 was found to be 4-fold more potent than TXA707 against a library of 55 methicillin-sensitive S. aureus (MSSA) and MRSA clinical isolates, including MRSA isolates resistant to vancomycin and linezolid. TXH9179 was also associated with a lower frequency of resistance relative to TXA707 in all but one of the MSSA and MRSA isolates examined, with the observed resistance being due to mutations in the ftsZ gene. TXH9179 induced changes in MRSA cell morphology, cell division, and FtsZ localization are fully consistent with its actions as a FtsZ inhibitor. Crystallographic studies demonstrate the direct interaction of TXH9179 with S. aureus FtsZ (SaFtsZ), while delineating the key molecular contacts that drive complex formation. TXH9179 was not associated with any mammalian cytotoxicity, even at a concentration 10-fold greater than that producing antistaphylococcal activity. In serum, the carboxamide prodrug of TXH9179 (TXH1033) is rapidly hydrolyzed to TXH9179 by serum acetylcholinesterases. Significantly, both intravenously and orally administered TXH1033 exhibited enhanced in vivo efficacy relative to the carboxamide prodrug of TXA707 (TXA709) in treating a mouse model of systemic (peritonitis) MRSA infection. Viewed as a whole, our results highlight TXH9179 as a promising new benzamide FtsZ inhibitor worthy of further development.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Pró-Fármacos , Infecções Estafilocócicas , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/química , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Proteínas do Citoesqueleto/química , Linezolida/farmacologia , Linezolida/uso terapêutico , Mamíferos , Meticilina/farmacologia , Meticilina/uso terapêutico , Testes de Sensibilidade Microbiana , Pró-Fármacos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Vancomicina/farmacologia
20.
Behav Sci (Basel) ; 13(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36829349

RESUMO

Suicide is considered a public health problem that affects families worldwide. Family functioning is the capability of the family system to fulfill needs during the stages of its development. In this study, we focused on evaluating family cohesion and adaptability in a group of adolescents who had attempted suicide and were hospitalized at a hospital for mental health disorders, compared to a control group. Methods: based on Olson's circumplex model, we used the FACES III scale to gain insights into the family functioning of both suicidal and control groups. Results: The case group presented lower scores in cohesion and adaptability compared to the control group, with moderate effect-size for cohesion (Cohen's d/r test = 1.217/0.52) and low effect-size for adaptability (Cohen's d/r test = 0.746/0.35) (p < 0.001 for both variables), and also presented predominantly disengaged families (72.5% in the case group vs. 27.5% in the control group) and structured families (45% in the case group vs. 23.8% in the control group). The type of family described by the adolescents with a history of suicide attempts may explain the presence of low self-esteem and little emotional support usually present in this type of patient.

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