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ESKAPE pathogens, a notorious consortium comprising Enterococcusfaecium, Staphylococcusaureus, Klebsiellapneumoniae, Acinetobacterbaumannii, Pseudomonasaeruginosa, and Enterobacter species, pose formidable challenges in healthcare settings due to their multidrug-resistant nature. The increasing global cases of antimicrobial-resistant ESKAPE pathogens are closely related to their remarkable ability to form biofilms. Thus, understanding the unique mechanisms of antimicrobial resistance of ESKAPE pathogens and the innate resilience of biofilms against traditional antimicrobial agents is important for developing innovative strategies to establish effective control methods against them. This review offers a thorough analysis of biofilm dynamics, with a focus on the general mechanisms of biofilm formation, the significant contribution of persister cells in the resistance mechanisms, and the recurrence of biofilms in comparison to planktonic cells. Additionally, this review highlights the potential strategies of nanoparticles for managing biofilms in the ESKAPE group of pathogens. Nanoparticles, with their unique physicochemical properties, provide promising opportunities for disrupting biofilm structures and improving antimicrobial effectiveness. The review has explored interactions between nanoparticles and biofilms, covering a range of nanoparticle types such as metal, metal-oxide, surface-modified, and functionalized nanoparticles, along with organic nanoparticles and nanomaterials. The additional focus of this review also encompasses green synthesis techniques of nanoparticles that involve plant extract and supernatants from bacterial and fungal cultures as reducing agents. Furthermore, the use of nanocomposites and nano emulsions in biofilm management of ESKAPE is also discussed. To conclude, the review addresses the current obstacles and future outlooks in nanoparticle-based biofilm management, stressing the necessity for further research and development to fully exploit the potential of nanoparticles in addressing biofilm-related challenges.
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BACKGROUND: Identifying local recurrences in breast cancer from patient data sets is important for clinical research and practice. Developing a model using natural language processing and machine learning to identify local recurrences in breast cancer patients can reduce the time-consuming work of a manual chart review. METHODS: We design a novel concept-based filter and a prediction model to detect local recurrences using EHRs. In the training dataset, we manually review a development corpus of 50 progress notes and extract partial sentences that indicate breast cancer local recurrence. We process these partial sentences to obtain a set of Unified Medical Language System (UMLS) concepts using MetaMap, and we call it positive concept set. We apply MetaMap on patients' progress notes and retain only the concepts that fall within the positive concept set. These features combined with the number of pathology reports recorded for each patient are used to train a support vector machine to identify local recurrences. RESULTS: We compared our model with three baseline classifiers using either full MetaMap concepts, filtered MetaMap concepts, or bag of words. Our model achieved the best AUC (0.93 in cross-validation, 0.87 in held-out testing). CONCLUSIONS: Compared to a labor-intensive chart review, our model provides an automated way to identify breast cancer local recurrences. We expect that by minimally adapting the positive concept set, this study has the potential to be replicated at other institutions with a moderately sized training dataset.
Assuntos
Neoplasias da Mama/diagnóstico , Aprendizado de Máquina , Processamento de Linguagem Natural , Recidiva Local de Neoplasia/diagnóstico , Estudos de Coortes , Registros Eletrônicos de Saúde , Feminino , Humanos , Reprodutibilidade dos Testes , Máquina de Vetores de Suporte , Unified Medical Language SystemRESUMO
Adaptation of the organism to potassium (K+) deficiency requires precise coordination among organs involved in K+ homeostasis, including muscle, liver, and kidney. How the latter performs functional and molecular changes to ensure K+ retention is not well understood. Here, we investigated the role of ubiquitin-protein ligase NEDD4-2, which negatively regulates the epithelial sodium channel (ENaC), Na+/Cl- cotransporter (NCC), and with no-lysine-kinase 1 (WNK1). After dietary K+ restriction for 2 weeks, compared with control littermates, inducible renal tubular NEDD4-2 knockout (Nedd4LPax8/LC1 ) mice exhibited severe hypokalemia and urinary K+ wasting. Notably, expression of the ROMK K+ channel did not change in the distal convoluted tubule and decreased slightly in the cortical/medullary collecting duct, whereas BK channel abundance increased in principal cells of the connecting tubule/collecting ducts. However, K+ restriction also enhanced ENaC expression in Nedd4LPax8/LC1 mice, and treatment with the ENaC inhibitor, benzamil, reversed excessive K+ wasting. Moreover, K+ restriction increased WNK1 and WNK4 expression and enhanced SPAK-mediated NCC phosphorylation in Nedd4LPax8/LC1 mice, with no change in total NCC. We propose a mechanism in which NEDD4-2 deficiency exacerbates hypokalemia during dietary K+ restriction primarily through direct upregulation of ENaC, whereas increased BK channel expression has a less significant role. These changes outweigh the compensatory antikaliuretic effects of diminished ROMK expression, increased NCC phosphorylation, and enhanced WNK pathway activity in the distal convoluted tubule. Thus, NEDD4-2 has a crucial role in K+ conservation through direct and indirect effects on ENaC, distal nephron K+ channels, and WNK signaling.
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Adaptação Fisiológica , Complexos Endossomais de Distribuição Requeridos para Transporte/fisiologia , Hipopotassemia/fisiopatologia , Túbulos Renais Distais/enzimologia , Ubiquitina-Proteína Ligases/fisiologia , Animais , Rim/fisiopatologia , Camundongos , Ubiquitina-Proteína Ligases Nedd4 , Fatores de TempoRESUMO
Even in the vaccine era, Streptococcus pneumoniae (the pneumococcus) remains a leading cause of otitis media, a significant public health burden, in large part because of the high prevalence of nasal colonization with the pneumococcus in children. The primary pneumococcal neuraminidase, NanA, which is a sialidase that catalyzes the cleavage of terminal sialic acids from host glycoconjugates, is involved in both of these processes. Coinfection with influenza A virus, which also expresses a neuraminidase, exacerbates nasal colonization and disease by S. pneumoniae, in part via the synergistic contributions of the viral neuraminidase. The specific role of its pneumococcal counterpart, NanA, in this interaction, however, is less well understood. We demonstrate in a mouse model that NanA-deficient pneumococci are impaired in their ability to cause both nasal colonization and middle ear infection. Coinfection with neuraminidase-expressing influenza virus and S. pneumoniae potentiates both colonization and infection but not to wild-type levels, suggesting an intrinsic role of NanA. Using in vitro models, we show that while NanA contributes to both epithelial adherence and biofilm viability, its effect on the latter is actually independent of its sialidase activity. These data indicate that NanA contributes both enzymatically and nonenzymatically to pneumococcal pathogenesis and, as such, suggest that it is not a redundant bystander during coinfection with influenza A virus. Rather, its expression is required for the full synergism between these two pathogens.
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Biofilmes , Vírus da Influenza A/fisiologia , Neuraminidase/metabolismo , Otite Média/microbiologia , Otite Média/virologia , Streptococcus pneumoniae/fisiologia , Simbiose , Animais , Aderência Bacteriana , Modelos Animais de Doenças , Ativação Enzimática , Feminino , Camundongos , Mucosa Nasal/microbiologia , Neuraminidase/genéticaRESUMO
The stimulation of postprandial K(+) clearance involves aldosterone-independent and -dependent mechanisms. In this context, serum- and glucocorticoid-induced kinase (SGK)1, a ubiquitously expressed kinase, is one of the primary aldosterone-induced proteins in the aldosterone-sensitive distal nephron. Germline inactivation of SGK1 suggests that this kinase is fundamental for K(+) excretion under conditions of K(+) load, but the specific role of renal SGK1 remains elusive. To avoid compensatory mechanisms that may occur during nephrogenesis, we used inducible, nephron-specific Sgk1(Pax8/LC1) mice to assess the role of renal tubular SGK1 in K(+) regulation. Under a standard diet, these animals exhibited normal K(+) handling. When challenged by a high-K(+) diet, they developed severe hyperkalemia accompanied by a defect in K(+) excretion. Molecular analysis revealed reduced neural precursor cell expressed developmentally downregulated protein (NEDD)4-2 phosphorylation and total expression. γ-Epithelial Na(+) channel (ENaC) expression and α/γENaC proteolytic processing were also decreased in mutant mice. Moreover, with no lysine kinase (WNK)1, which displayed in control mice punctuate staining in the distal convoluted tubule and diffuse distribution in the connecting tubule/cortical colleting duct, was diffused in the distal convoluted tubule and less expressed in the connecting tubule/collecting duct of Sgk(Pax8/LC1) mice. Moreover, Ste20-related proline/alanine-rich kinase phosphorylation, and Na(+)-Cl(-) cotransporter phosphorylation/apical localization were reduced in mutant mice. Consistent with the altered WNK1 expression, increased renal outer medullary K(+) channel apical localization was observed. In conclusion, our data suggest that renal tubular SGK1 is important in the regulation of K(+) excretion via the control of NEDD4-2, WNK1, and ENaC.
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Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Canais Epiteliais de Sódio/metabolismo , Proteínas Imediatamente Precoces/deficiência , Proteínas Imediatamente Precoces/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Potássio/urina , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Bloqueadores/farmacologia , Dieta , Regulação da Expressão Gênica , Túbulos Renais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Ubiquitina-Proteína Ligases Nedd4 , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/imunologia , Potássio na Dieta/farmacologia , Proteína Quinase 1 Deficiente de Lisina WNKRESUMO
Flow-induced K(+) secretion in the aldosterone-sensitive distal nephron is mediated by high-conductance Ca(2+)-activated K(+) (BK) channels. Familial hyperkalemic hypertension (pseudohypoaldosteronism type II) is an inherited form of hypertension with decreased K(+) secretion and increased Na(+) reabsorption. This disorder is linked to mutations in genes encoding with-no-lysine kinase 1 (WNK1), WNK4, and Kelch-like 3/Cullin 3, two components of an E3 ubiquitin ligase complex that degrades WNKs. We examined whether the full-length (or "long") form of WNK1 (L-WNK1) affected the expression of BK α-subunits in HEK cells. Overexpression of L-WNK1 promoted a significant increase in BK α-subunit whole cell abundance and functional channel expression. BK α-subunit abundance also increased with coexpression of a kinase dead L-WNK1 mutant (K233M) and with kidney-specific WNK1 (KS-WNK1), suggesting that the catalytic activity of L-WNK1 was not required to increase BK expression. We examined whether dietary K(+) intake affected L-WNK1 expression in the aldosterone-sensitive distal nephron. We found a paucity of L-WNK1 labeling in cortical collecting ducts (CCDs) from rabbits on a low-K(+) diet but observed robust staining for L-WNK1 primarily in intercalated cells when rabbits were fed a high-K(+) diet. Our results and previous findings suggest that L-WNK1 exerts different effects on renal K(+) secretory channels, inhibiting renal outer medullary K(+) channels and activating BK channels. A high-K(+) diet induced an increase in L-WNK1 expression selectively in intercalated cells and may contribute to enhanced BK channel expression and K(+) secretion in CCDs.
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Túbulos Renais Coletores/enzimologia , Potássio na Dieta/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Eliminação Renal , Animais , Feminino , Regulação Enzimológica da Expressão Gênica , Células HEK293 , Humanos , Túbulos Renais Coletores/citologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Potenciais da Membrana , Camundongos , Antígenos de Histocompatibilidade Menor , Mutação , Potássio na Dieta/administração & dosagem , Proteínas Serina-Treonina Quinases/genética , Coelhos , Transfecção , Regulação para Cima , Proteína Quinase 1 Deficiente de Lisina WNKRESUMO
Fabry nephropathy is a major cause of morbidity and premature death in patients with Fabry disease (FD), a rare X-linked lysosomal storage disorder. Gb3, the main substrate of α-galactosidase A (α-Gal A), progressively accumulates within cells in a variety of tissues. Establishment of cell models has been useful as a tool for testing hypotheses of disease pathogenesis. We applied CRISPR/Cas9 genome editing technology to the GLA gene to develop human kidney cell models of FD in human immortalized podocytes, which are the main affected renal cell type. Our podocytes lack detectable α-Gal A activity and have increased levels of Gb3. To explore different pathways that could have distinct patterns of activation under conditions of α-gal A deficiency, we used a high-throughput antibody array to perform phosphorylation profiling of CRISPR/Cas9-edited and control podocytes. Changes in both total protein levels and in phosphorylation status per site were observed. Analysis of our candidate proteins suggests that multiple signaling pathways are impaired in FD.
Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Doença de Fabry/metabolismo , Rim/metabolismo , Podócitos/metabolismo , alfa-Galactosidase/metabolismo , Linhagem Celular , Doença de Fabry/genética , Doença de Fabry/patologia , Humanos , Rim/patologia , Podócitos/patologia , Transdução de Sinais/fisiologia , alfa-Galactosidase/genéticaRESUMO
Sodium-coupled SLC12 cation chloride cotransporters play important roles in cell volume and chloride homeostasis, epithelial fluid secretion, and renal tubular salt reabsorption. These cotransporters are phosphorylated and activated indirectly by With-No-Lysine (WNK) kinases through their downstream effector kinases, Ste20- and SPS1-related proline alanine-rich kinase (SPAK) and oxidative stress-responsive kinase 1 (OSR1). Multiple WNK kinases can coexist within a single cell type, although their relative contributions to SPAK/OSR1 activation and salt transport remain incompletely understood. Deletion of specific WNKs from cells that natively express a functional WNK-SPAK/OSR1 network will help resolve these knowledge gaps. Here, we outline a simple method to selectively knock out full-length WNK1 expression from mammalian cells using RNA-guided clustered regularly interspaced short palindromic repeats/Cas9 endonucleases. Two clonal cell lines were generated by using a single-guide RNA (sgRNA) targeting exon 1 of the WNK1 gene, which produced indels that abolished WNK1 protein expression. Both cell lines exhibited reduced endogenous WNK4 protein abundance, indicating that WNK1 is required for WNK4 stability. Consistent with an on-target effect, the reduced WNK4 abundance was associated with increased expression of the KLHL3/cullin-3 E3 ubiquitin ligase complex and was rescued by exogenous WNK1 overexpression. Although the morphology of the knockout cells was indistinguishable from control, they exhibited low baseline SPAK/OSR1 activity and failed to trigger regulatory volume increase after hypertonic stress, confirming an essential role for WNK1 in cell volume regulation. Collectively, our data show how this new, powerful, and accessible gene-editing technology can be used to dissect and analyze WNK signaling networks.
Assuntos
Sistemas CRISPR-Cas , Técnicas de Silenciamento de Genes/métodos , Genoma Humano , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Forma Celular , Tamanho Celular , Proteínas Culina/genética , Proteínas Culina/metabolismo , Regulação para Baixo , Éxons , Genótipo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas dos Microfilamentos , Antígenos de Histocompatibilidade Menor , Pressão Osmótica , Fenótipo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade Proteica , Transdução de Sinais , Fatores de Tempo , Transfecção , Proteína Quinase 1 Deficiente de Lisina WNKRESUMO
Dispersion enables the transition from the biofilm to the planktonic growth state in response to various cues. While several Pseudomonas aeruginosa proteins, including BdlA and the c-di-GMP phosphodiesterases DipA, RbdA, and NbdA, have been shown to be required for dispersion to occur, little is known about dispersion cue sensing and the signalling translating these cues into the modulation c-di-GMP levels to enable dispersion. Using glutamate-induced dispersion as a model, we report that dispersion-inducing nutrient cues are sensed via an outside-in signalling mechanism by the diguanylate cyclase NicD belonging to a family of seven transmembrane (7TM) receptors. NicD directly interacts with BdlA and the phosphodiesterase DipA, with NicD, BdlA, and DipA being part of the same pathway required for dispersion. Glutamate sensing by NicD results in NicD dephosphorylation and increased cyclase activity. Active NicD contributes to the non-processive proteolysis and activation of BdlA via phosphorylation and temporarily elevated c-di-GMP levels. BdlA, in turn, activates DipA, resulting in the overall reduction of c-di-GMP levels. Our results provide a basis for understanding the signalling mechanism based on NicD to induce biofilm dispersion that may be applicable to various biofilm-forming species and may have implications for the control of biofilm-related infections.
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Biofilmes/crescimento & desenvolvimento , Proteínas de Escherichia coli/metabolismo , Alimentos , Fósforo-Oxigênio Liases/metabolismo , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/fisiologia , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Ácido Glutâmico/metabolismo , Fosforilação , Ligação Proteica , Processamento de Proteína Pós-Traducional , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Transdução de SinaisRESUMO
The thiazide-sensitive NaCl cotransporter (NCC) is the primary mediator of salt reabsorption in the distal convoluted tubule and is a key determinant of the blood pressure set point. Given its complex topology, NCC is inefficiently processed and prone to endoplasmic reticulum (ER)-associated degradation (ERAD), although the mechanisms governing this process remain obscure. Here, we identify factors that impact the ER quality control of NCC. Analyses of NCC immunoprecipitates revealed that the cotransporter formed complexes with the core chaperones Hsp90, Hsp70, and Hsp40. Disruption of Hsp90 function accelerated NCC degradation, suggesting that Hsp90 promotes NCC folding. In addition, two cochaperones, the C terminus of Hsp70-interacting protein (CHIP) and the Hsp70/Hsp90 organizer protein, were associated with NCC. Although CHIP, an E3 ubiquitin ligase, promoted NCC ubiquitination and ERAD, the Hsp70/Hsp90 organizer protein stabilized NCC turnover, indicating that these two proteins differentially remodel the core chaperone systems to favor cotransporter degradation and biogenesis, respectively. Adjusting the folding environment in mammalian cells via reduced temperature enhanced NCC biosynthetic trafficking, increased Hsp90-NCC interaction, and diminished binding to Hsp70. In contrast, cotransporters harboring disease-causing mutations that impair NCC biogenesis failed to escape ERAD as efficiently as the wild type protein when cells were incubated at a lower temperature. Instead, these mutants interacted more strongly with Hsp70, Hsp40, and CHIP, consistent with a role for the Hsp70/Hsp40 system in selecting misfolded NCC for ERAD. Collectively, these observations indicate that Hsp70 and Hsp90 comprise two functionally distinct ER quality control checkpoints that sequentially monitor NCC biogenesis.
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Retículo Endoplasmático/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Complexos Multiproteicos/metabolismo , Proteólise , Receptores de Droga/metabolismo , Simportadores/metabolismo , Animais , Linhagem Celular , Cães , Retículo Endoplasmático/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Humanos , Camundongos , Complexos Multiproteicos/genética , Dobramento de Proteína , Receptores de Droga/genética , Membro 3 da Família 12 de Carreador de Soluto , Simportadores/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The epithelial sodium channel, ENaC, plays a critical role in maintaining salt and water homeostasis, and not surprisingly defects in ENaC function are associated with disease. Like many other membrane-spanning proteins, this trimeric protein complex folds and assembles inefficiently in the endoplasmic reticulum (ER), which results in a substantial percentage of the channel being targeted for ER-associated degradation (ERAD). Because the spectrum of factors that facilitates the degradation of ENaC is incomplete, we developed yeast expression systems for each ENaC subunit. We discovered that a conserved Hsp70-like chaperone, Lhs1, is required for maximal turnover of the ENaC α subunit. By expressing Lhs1 ATP binding mutants, we also found that the nucleotide exchange properties of this chaperone are dispensable for ENaC degradation. Consistent with the precipitation of an Lhs1-αENaC complex, Lhs1 holdase activity was instead most likely required to support the ERAD of αENaC. Moreover, a complex containing the mammalian Lhs1 homolog GRP170 and αENaC co-precipitated, and GRP170 also facilitated ENaC degradation in human, HEK293 cells, and in a Xenopus oocyte expression system. In both yeast and higher cell types, the effect of Lhs1 on the ERAD of αENaC was selective for the unglycosylated form of the protein. These data establish the first evidence that Lhs1/Grp170 chaperones can act as mediators of ERAD substrate selection.
Assuntos
Degradação Associada com o Retículo Endoplasmático , Canais Epiteliais de Sódio/metabolismo , Glicoproteínas/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Trifosfato de Adenosina/metabolismo , Amilorida/farmacologia , Animais , Retículo Endoplasmático/metabolismo , Canais Epiteliais de Sódio/genética , Feminino , Glicoproteínas/genética , Células HEK293 , Proteínas de Choque Térmico HSP70/genética , Humanos , Immunoblotting , Transporte de Íons/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Mutação , Oócitos/metabolismo , Oócitos/fisiologia , Ligação Proteica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Sódio/metabolismo , XenopusRESUMO
Objective: Previous studies have shown that the cleavage of Sirt1 contributes to the development of osteoarthritis (OA). In fact, OA was effectively abrogated by the intra-articular (IA) administration of two compounds, one blocking Sirt1 cleavage (CA074me) and the other activating Sirt1 (SRT1720), using a post-traumatically induced model (PTOA) in young female mice. In this study, we attempted to understand if this local treatment is effective in preventing age-associated OA (AOA) progression and symptoms. Design: A group of 17-month-old female C57BL/6J mice were IA administered with CA074me and/or SRT1720 or their combination. Joint histopathological analysis and bone histomorphometry were carried out, with an assessment of knee mechanical hyperalgesia. A serum analysis for NT/CT Sirt1 was carried out along with immunohistochemistry for articular cartilage to detect p16INK4A or γH2A.X. Similarly, meniscal cartilage was monitored for Lef1 and Col1a1 deposition. The data were compared for young female mice subjected to post-traumatic OA (PTOA). Results: Similar to PTOA, combination-treated AOA exhibited improved knee hyperalgesia, yet structural improvements were undetected, corresponding to unchanged NT/CT Sirt1 serum levels. Both AOA and PTOA exhibited unchanged staining for nuclear p16INK4A or γH2A.X and lacked a correlation with OA severity. Contrarily to PTOA, the combination treatment with AOA did not exhibit a local reduction in the Lef1 and Col1 targets. Conclusions: When targeting Sirt1 cleavage, the PTOA and AOA models exhibited a similar pain response to the combination treatment; however, they displayed diverse structural outcomes for joint-related damage, related to Lef1-dependent signaling. Interestingly, nuclear p16INK4A was unaffected in both models, regardless of the treatment's effectiveness. Finally, these findings highlight the variations in the responses between two highly researched OA preclinical models, reflecting OA pathophysiology heterogeneity and variations in gender-related drug-response mechanisms.
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Cartilagem Articular , Osteoartrite , Sirtuína 1 , Animais , Feminino , Camundongos , Inibidor p16 de Quinase Dependente de Ciclina , Hiperalgesia , Camundongos Endogâmicos C57BL , Osteoartrite/tratamento farmacológico , Osteoartrite/etiologia , Sirtuína 1/efeitos dos fármacosRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major causes of hospital and community-acquired infections. Fewer drugs, such as vancomycin, teicoplanin, and daptomycin, are effective against it, but they come with high toxicity. Fifth-generation cephalosporins like ceftaroline and second-generation cefuroxime are effective against MRSA. Limited studies are available on ceftaroline resistance in the literature. This study was undertaken to determine ceftaroline resistance in MRSA in a tertiary care hospital in Eastern India. A cross-sectional, hospital-based study was carried out with MRSA isolates obtained from various clinical samples of patients. Identification of the isolates to the species level was performed by an automated Vitek system, and selected samples were genotypically confirmed by detecting the mecA gene via real-time PCR. Out of a total of 334 Staphylococcus aureus isolates examined in this study, the prevalence of MRSA was seen in 59.3% (198/334), and methicillin-sensitive Staphylococcus aureus was in 40.7% (136/334). Of the total 198 MRSA isolates, ceftaroline intermediate MRSA was seen in 8.6% (17/198), and ceftaroline sensitive MRSA was in 91.4% (181/198), respectively. Among the 17 ceftaroline intermediate MRSA isolates, 88.2% (15/17) showed a minimum inhibitory concentration (MIC) of 2 µg/ml, and 11.8% (2/17) showed an MIC of 3 µg/ml. All the remaining 91.4% (181/198) isolates were sensitive to ceftaroline and showed an MIC ≤1 µg/ml. Real-time PCR confirmed the presence of the mecA gene in MRSA isolates. In this present study, not a single isolate was resistant to ceftaroline, suggesting that it, being a safer drug, can be used in place of glycopeptides such as vancomycin or teicoplanin and linezolid, where resistance has already been detected. The rational use of ceftaroline could be useful in clinical settings, and further studies will confirm the findings.
RESUMO
Although little is known regarding the mechanism of biofilm dispersion, it is becoming clear that this process coincides with alteration of cyclic di-GMP (c-di-GMP) levels. Here, we demonstrate that dispersion by Pseudomonas aeruginosa in response to sudden changes in nutrient concentrations resulted in increased phosphodiesterase activity and reduction of c-di-GMP levels compared to biofilm and planktonic cells. By screening mutants inactivated in genes encoding EAL domains for nutrient-induced dispersion, we identified in addition to the previously reported ΔrbdA mutant a second mutant, the ΔdipA strain (PA5017 [dispersion-induced phosphodiesterase A]), to be dispersion deficient in response to glutamate, nitric oxide, ammonium chloride, and mercury chloride. Using biochemical and in vivo studies, we show that DipA associates with the membrane and exhibits phosphodiesterase activity but no detectable diguanylate cyclase activity. Consistent with these data, a ΔdipA mutant exhibited reduced swarming motility, increased initial attachment, and polysaccharide production but only somewhat increased biofilm formation and c-di-GMP levels. DipA harbors an N-terminal GAF (cGMP-specific phosphodiesterases, adenylyl cyclases, and FhlA) domain and two EAL motifs within or near the C-terminal EAL domain. Mutational analyses of the two EAL motifs of DipA suggest that both are important for the observed phosphodiesterase activity and dispersion, while the GAF domain modulated DipA function both in vivo and in vitro without being required for phosphodiesterase activity. Dispersion was found to require protein synthesis and resulted in increased dipA expression and reduction of c-di-GMP levels. We propose a role of DipA in enabling dispersion in P. aeruginosa biofilms.
Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes , Diester Fosfórico Hidrolases/metabolismo , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Membrana Celular/enzimologia , Membrana Celular/genética , Membrana Celular/metabolismo , GMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica , Diester Fosfórico Hidrolases/química , Diester Fosfórico Hidrolases/genética , Estrutura Terciária de Proteína , Transporte Proteico , Pseudomonas aeruginosa/química , Pseudomonas aeruginosa/genéticaRESUMO
To improve utilization and reduce the cost of maintaining mobile clinical equipment, healthcare organization leaders should do the following: Select an initial asset group to target. Conduct a physical inventory. Evaluate the organization's asset "ecosystem." Optimize workflow processes. Phase in new processes, and phase out inventory. Devote time to change management. Develop a replacement strategy.
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Orçamentos , Equipamentos e Provisões Hospitalares/economia , Equipamentos e Provisões Hospitalares/estatística & dados numéricos , Administração Financeira de Hospitais/economia , Eficiência Organizacional/economia , Estados UnidosRESUMO
INTRODUCTION: Nanoemulsion-based drug delivery approaches have witnessed massive acceptance over the years and acquired a significant foothold owing to their tremendous benefits over the others. It has widely been used for transdermal delivery of hydrophobic and hydrophilic drugs with solubility, lipophilicity, and bioavailability issues. AREAS COVERED: The review highlights the recent advancements and applications of transdermal nanoemulsions. Their utilities and characteristics, clinical pertinence showcasing intellectual properties and advancements, potential in treating disorders accompanying liquid, semisolid, and solid dosage forms, the ability to modulate a drug's physicochemical properties, and regulatory status are thoroughly summarized. EXPERT OPINION: Despite tremendous therapeutic utilities and extensive investigations, the transdermal nanoemulsion-based technologies yet tackles several challenges such as optimum use of surfactant mixtures, economic burden due to high energy consumption during production, lack of concrete regulatory requirement, etc. Provided with the concrete guidelines on the safe use of surfactants, stability, use of scalable and economical methods, and the use of NE as a transdermal system would solve the purpose best as nanoemulsion shows remarkable improvement in drug release profiles and bioavailability of many drugs. Nevertheless, a better understanding of nanoemulsion technology holds a promising outlook and would land more opportunities and better delivery outcomes.
Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Administração Cutânea , Disponibilidade Biológica , Liberação Controlada de Fármacos , Emulsões/química , Nanopartículas/químicaRESUMO
BACKGROUND: The gold standard test for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recommended by WHO is real-time reverse transcription polymerase chain reaction (RT-PCR), which has a turnaround time of five to six hours. Abbott ID NOW (Abbott Diagnostics Scarborough, Inc., Scarborough, ME, USA), the cartridge-based loop-mediated isothermal amplification (LAMP) assay, was approved by FDA for Emergency Use Authorization as rapid point of care testing. The present study was planned to evaluate the performance of the cartridge-based Abbott ID NOW test by comparing it to the currently used standard probe-based real-time RT-PCR method for detection of SARS-CoV-2. METHODOLOGY: A cross-sectional study was conducted in a tertiary care hospital in the eastern part of India after getting institutional ethics committee (IEC) approval. Two hundred fifty-nine cases of various age groups of both sexes who were advised for testing for SARS-CoV-2 were included in the study. Nasopharyngeal swabs were collected according to protocol advisory by the Indian Council of Medical Research (ICMR), India. Dry swabs were sent for Abbott ID NOW testing and swabs in viral transport medium were sent for probe-based RT-PCR assay using the CoviPath kit (Thermo Fisher Scientific, Bangalore, India). The data were collected and statistical analysis was performed using Statistical Package for Social Sciences (SPSS) (IBM Corp., Armonk, NY, USA). Sensitivity, specificity, positive and negative predictive values for ID NOW were calculated taking RT-PCR as the gold standard. Results: Out of 259 patients enrolled in the study, 49% were symptomatic for coronavirus disease 2019 (COVID-19). The prevalence rate of SARS-CoV-2 was 20.84% among the study population. Sensitivity and specificity, positive and negative predictive values of ID NOW test in comparison to RT-PCR assay was found to be 87%, 98%, 92.1% and 96.8% respectively. ID NOW detected seven out of 54 (12.9%) cases as false negative who were found to be positive with RT-PCR, with mean Ct value of the target genes >34. CONCLUSIONS: In this study the overall sensitivity for ID NOW assay was found to be lower, but specificity, positive and negative predictive values were found to be higher. It had the highest correlation to RT-PCR among symptomatic patients and at higher viral loads. Due to the ease of use and shortest result time for detecting COVID-19, ID NOW test could be used as a point-of-care test. But for all tests, the results should be interpreted according to the clinical and epidemiological context.
RESUMO
Trichomes show 47 morphological phenotypes, while literature reports only two root hair phenotypes in all plants. However, could hair-like structures exist below-ground in a similar wide range of morphologies like trichomes? Genetic mutants and root hair stress phenotypes point to the possibility of uncharacterized morphological variation existing belowground. For example, such root hairs in Arabidopsis (Arabidopsis thaliana) can be wavy, curled, or branched. We found hints in the literature about hair-like structures that emerge before root hairs belowground. As such, these early emerging hair structures can be potential exceptions to the contrasting morphological variation between trichomes and root hairs. Here, we show a previously unreported 'hooked' hair structure growing below-ground in common bean. The unique 'hooking' shape distinguishes the 'hooked hair' morphologically from root hairs. Currently, we cannot fully characterize the phenotype of our observation due to the lack of automated methods for phenotyping root hairs. This phenotyping bottleneck also handicaps the discovery of more morphology types that might exist below-ground as manual screening across species is slower than computer-assisted high-throughput screening.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fenótipo , Raízes de Plantas/genética , Tricomas/genéticaRESUMO
Pathophysiological defects in water homeostasis can lead to renal failure. Likewise, common genetic disorders associated with abnormal cytoskeletal dynamics in the kidney collecting ducts and perturbed calcium and cAMP signaling in the ciliary compartment contribute to chronic kidney failure. We show that collecting ducts in mice lacking the A-Kinase anchoring protein AKAP220 exhibit enhanced development of primary cilia. Mechanistic studies reveal that AKAP220-associated protein phosphatase 1 (PP1) mediates this phenotype by promoting changes in the stability of histone deacetylase 6 (HDAC6) with concomitant defects in actin dynamics. This proceeds through a previously unrecognized adaptor function for PP1 as all ciliogenesis and cytoskeletal phenotypes are recapitulated in mIMCD3 knock-in cells expressing a phosphatase-targeting defective AKAP220-ΔPP1 mutant. Pharmacological blocking of local HDAC6 activity alters cilia development and reduces cystogenesis in kidney-on-chip and organoid models. These findings identify the AKAP220-PPI-HDAC6 pathway as a key effector in primary cilia development.
Assuntos
Proteínas de Ancoragem à Quinase A/metabolismo , Cílios/metabolismo , Desacetilase 6 de Histona/metabolismo , Homeostase , Rim/metabolismo , Proteína Fosfatase 1/metabolismo , Actinas/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Células HEK293 , Inibidores de Histona Desacetilases/farmacologia , Humanos , Túbulos Renais Coletores , Camundongos , Organoides/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Breast magnetic resonance imaging (MRI) delineates disease extent sensitively in newly diagnosed breast cancer patients, but improved cancer outcomes are uncertain. Young women, for whom mammography is less sensitive, are expected to benefit from MRI-based resection. We identified 512 women aged ≤50 years, undergoing breast-conserving treatment (BCT: tumor-free resection margins and radiotherapy) during 2006-2013 through Northwestern Medicine database queries; 64.5% received preoperative MRI and 35.5% did not. Tumor and treatment parameters were similar between groups. We estimated the adjusted hazard ratios (aHR) for local and distant recurrences (LR and DR), using multivariable regression models, accounting for important therapeutic and prognostic parameters. LR rate with MRI use was 7.9 vs. 8.2% without MRI, aHR = 1.03 (95% CI 0.53-1.99). DR rate was 6.4 vs. 6.6%, aHR = 0.89 (95% CI 0.43-1.84). In 119 women aged ≤40, results were similar to LR aHR = 1.82 (95% CI 0.43-7.76) and DR aHR = 0.93 (95% CI 0.26-3.34). Sensitivity analyses showed similar results. The use of preoperative MRI in women aged ≤50 years should be reconsidered until there is proof of benefit.