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1.
Microbiol Resour Announc ; : e0112223, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634680

RESUMO

We report the whole-genome sequence and antibiotic-resistance gene profile of an Acinetobacter calcoaceticus isolate, designated AC001_UM, taken from soil along the Red River in Winnipeg, Manitoba, Canada. The genome comprised 3,916,544 nucleotides (GC content: 38.7%). Antibiotic-resistance gene analysis revealed a class D ß-lactamase and three efflux pump families.

2.
mSphere ; 9(3): e0074123, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38440986

RESUMO

Acinetobacter baumannii is a Gram-negative, opportunistic pathogen that causes infections in the immunocompromised. With a high incidence of muti-drug resistance, carbapenem-resistant A. baumannii is designated as a priority 1 pathogen by the WHO. The current literature has expertly characterized clinical isolates of A. baumannii. As the challenge of these infections has recently been classified as a One Health issue, we set out to explore the diversity of isolates from human and non-clinical sources, such as agricultural surface water, urban streams, various effluents from wastewater treatment plants, and food (tank milk); and, importantly, these isolates came from a wide geographic distribution. Phylogenomic analysis considering almost 200 isolates showed that our diverse set is well-differentiated from the main international clones of A. baumannii. We discovered novel sequence types in both hospital and non-clinical settings and five strains that overexpress the resistance-nodulation-division efflux pump adeIJK without changes in susceptibility reflected by this overexpression. Furthermore, we detected a bla ADC-79 in a non-human isolate despite its sensitivity to all antibiotics. There was no significant differentiation between the virulence profiles of clinical and non-clinical isolates in the Galleria mellonella insect model of virulence, suggesting that virulence is neither dependent on geographic origin nor isolation source. The detection of antibiotic resistance and virulence genes in non-human strains suggests that these isolates may act as a genetic reservoir for clinical strains. This endorses the notion that in order to combat multi-drug-resistant infection caused by A. baumannii, a One Health approach is required, and a deeper understanding of non-clinical strains must be achieved.IMPORTANCEThe global crisis of antibiotic resistance is a silent one. More and more bacteria are becoming resistant to all antibiotics available for treatment, leaving no options remaining. This includes Acinetobacter baumannii. This Gram-negative, opportunistic pathogen shows a high frequency of multi-drug resistance, and many strains are resistant to the last-resort drugs carbapenem and colistin. Research has focused on strains of clinical origin, but there is a knowledge gap regarding virulence traits, particularly how A. baumannii became the notorious pathogen of today. Antibiotic resistance and virulence genes have been detected in strains from animals and environmental locations such as grass and soil. As such, A. baumannii is a One Health concern, which includes the health of humans, animals, and the environment. Thus, in order to truly combat the antibiotic resistance crisis, we need to understand the antibiotic resistance and virulence gene reservoirs of this pathogen under the One Health continuum.


Assuntos
Acinetobacter baumannii , Anti-Infecciosos , Animais , Humanos , Virulência/genética , Filogenia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética
3.
Lett Appl Microbiol ; 77(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460955

RESUMO

The Acinetobacter calcoaceticus-baumannii (ACB) complex is an often-overlooked group of nosocomial pathogens with a significant environmental presence. Rapid molecular screening methods for virulence, antimicrobial resistance, and toxin (VAT) genes are required to investigate the potential pathogenicity of environmental isolates. This study aimed to develop and apply novel ACB complex-specific multiplex PCR (mPCR) primers and protocols for the rapid detection of eight VAT genes. We optimized three single-tube mPCR assays using reference DNA from ACB complex and other Acinetobacter species. These assays were then applied to detect VAT genes in cultured ACB complex isolates recovered from clinical and environmental sources. Widespread detection of VAT genes in environmental isolates confirmed the validity, functionality, and applicability of these novel assays. Overall, the three newly developed ACB complex species-specific mPCR assays are rapid and simple tools that can be adopted in diagnostic and clinical lab settings. The detection of VAT genes in environmental isolates suggests that environmental niches could serve as a reservoir for potentially pathogenic ACB complex and warrants further investigation. The newly developed mPCR assays are specific, sensitive, and efficient, making them well-suited for high-throughput screening in epidemiological studies and evaluating the potential pathogenicity of ACB complex recovered from various sources.


Assuntos
Acinetobacter baumannii , Acinetobacter calcoaceticus , Toxinas Biológicas , Reação em Cadeia da Polimerase Multiplex/métodos , Virulência/genética , Antibacterianos/farmacologia , Acinetobacter calcoaceticus/genética , Farmacorresistência Bacteriana , Acinetobacter baumannii/genética
4.
J Biol Chem ; 300(4): 107202, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38508310

RESUMO

We are interested in the contribution of integrins and the extracellular matrix to epithelial differentiation in carcinomas. This study was motivated by our finding that the Hippo effectors YAP and TAZ can sustain the expression of laminin 332 (LM332), the predominant ECM ligand for the integrin ß4, in breast carcinoma cells with epithelial differentiation. More specifically, we observed that YAP and TAZ regulate the transcription of the LAMC2 subunit of LM332. Given that the ß4-LM332 axis is associated with epithelial differentiation and YAP/TAZ have been implicated in carcinoma de-differentiation, we sought to resolve this paradox. Here, we observed that the ß4 integrin sustains the expression of miR-200s that target the transcription factor ZEB1 and that ZEB1 has a pivotal role in determining the nature of YAP/TAZ-mediated transcription. In the presence of ß4, ZEB1 expression is repressed enabling YAP/TAZ/TEAD-mediated transcription of LAMC2. The absence of ß4, however, induces ZEB1, and ZEB1 binds to the LAMC2 promoter to inhibit LAMC2 transcription. YAP/TAZ-mediated regulation of LAMC2 has important functional consequences because we provide evidence that LM332 enables carcinoma cells to resist ferroptosis in concert with the ß4 integrin.

5.
Microbiol Spectr ; 12(3): e0314123, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38305192

RESUMO

The microbiological content of water is an ongoing concern in First Nations communities in Canada. Many communities lack water treatment plants and continue to be under drinking water advisories. However, lack of access to treatment plants is only a part of the problem as poor water distribution systems also contribute to the failure to provide safe drinking water. Here, we studied the microbial diversity and antibiotic resistome from water stored in cisterns from two First Nations communities in Manitoba, Canada. We found that the cistern water contained a high number of bacteria and showed the presence of diverse antimicrobial resistance genes. Interestingly, the bacterial diversity and antimicrobial resistance genes varied considerably from that of the untreated source water, indicating that the origin of contamination in the cistern water came from within the treatment plant or along the delivery route to the homes. Our study highlights the importance of proper maintenance of the water distribution system in addition to access to water treatment facilities to ensure a supply of safe water to First Nations communities in Canada.IMPORTANCEThe work described addresses a critical issue in First Nations communities in Canada-the microbiological content of water. Many of these communities lack access to water treatment plants and frequently experience drinking water advisories. This study focused on the microbial diversity and antibiotic resistome in water stored in cisterns within two First Nations communities in Manitoba, Canada. These findings reveal that cistern water, a common source of drinking water in these communities, contains a high number of bacteria and a wide range of antimicrobial resistance genes. This highlights a serious health risk as exposure to such water can lead to the spread of drug-resistant infections, posing a threat to the well-being of the residents.


Assuntos
Água Potável , Manitoba , Canadá , Bactérias/genética , Antibacterianos/farmacologia , Genes Bacterianos
6.
J Vis Exp ; (203)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38251724

RESUMO

Acinetobacter baumannii is recognized as a challenging Gram-negative pathogen due to its widespread resistance to antibiotics. It is crucial to comprehend the mechanisms behind this resistance to design new and effective therapeutic options. Unfortunately, our ability to investigate these mechanisms in A. baumannii is hindered by the paucity of suitable genetic manipulation tools. Here, we describe methods for utilizing a chromosomal mini-Tn7-based system to achieve single-copy gene expression in an A. baumannii strain that lacks functional RND-type efflux mechanisms. Single-copy insertion and inducible efflux pump expression are quite advantageous, as the presence of RND efflux operons on high-copy number plasmids is often poorly tolerated by bacterial cells. Moreover, incorporating recombinant mini-Tn7 expression vectors into the chromosome of a surrogate A. baumannii host with increased efflux sensitivity helps circumvent interference from other efflux pumps. This system is valuable not only for investigating uncharacterized bacterial efflux pumps but also for assessing the effectiveness of potential inhibitors targeting these pumps.


Assuntos
Acinetobacter baumannii , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Bactérias , Transporte Biológico , Expressão Gênica
7.
Can J Microbiol ; 70(1): 1-14, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37699258

RESUMO

Salicylic acids have been used in human and veterinary medicine for their anti-pyretic, anti-inflammatory, and analgesic properties for centuries. A key role of salicylic acid-immune modulation in response to microbial infection-was first recognized during studies of their botanical origin. The effects of salicylic acid on bacterial physiology are diverse. In many cases, they impose selective pressures leading to development of cross-resistance to antimicrobial compounds. Initial characterization of these interactions was in Escherichia coli, where salicylic acid activates the multiple antibiotic resistance (mar) operon, resulting in decreased antibiotic susceptibility. Studies suggest that stimulation of the mar phenotype presents similarly in closely related Enterobacteriaceae. Salicylic acids also affect virulence in many opportunistic pathogens by decreasing their ability to form biofilms and increasing persister cell populations. It is imperative to understand the effects of salicylic acid on bacteria of various origins to illuminate potential links between environmental microbes and their clinically relevant antimicrobial-resistant counterparts. This review provides an update on known effects of salicylic acid and key derivatives on a variety of bacterial pathogens, offers insights to possible potentiation of current treatment options, and highlights cellular regulatory networks that have been established during the study of this important class of medicines.


Assuntos
Anti-Infecciosos , Proteínas de Escherichia coli , Humanos , Proteínas de Escherichia coli/genética , Proteínas de Bactérias/genética , Escherichia coli , Ácido Salicílico/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
8.
Nature ; 624(7991): 415-424, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38092908

RESUMO

The basic plan of the retina is conserved across vertebrates, yet species differ profoundly in their visual needs1. Retinal cell types may have evolved to accommodate these varied needs, but this has not been systematically studied. Here we generated and integrated single-cell transcriptomic atlases of the retina from 17 species: humans, two non-human primates, four rodents, three ungulates, opossum, ferret, tree shrew, a bird, a reptile, a teleost fish and a lamprey. We found high molecular conservation of the six retinal cell classes (photoreceptors, horizontal cells, bipolar cells, amacrine cells, retinal ganglion cells (RGCs) and Müller glia), with transcriptomic variation across species related to evolutionary distance. Major subclasses were also conserved, whereas variation among cell types within classes or subclasses was more pronounced. However, an integrative analysis revealed that numerous cell types are shared across species, based on conserved gene expression programmes that are likely to trace back to an early ancestral vertebrate. The degree of variation among cell types increased from the outer retina (photoreceptors) to the inner retina (RGCs), suggesting that evolution acts preferentially to shape the retinal output. Finally, we identified rodent orthologues of midget RGCs, which comprise more than 80% of RGCs in the human retina, subserve high-acuity vision, and were previously believed to be restricted to primates2. By contrast, the mouse orthologues have large receptive fields and comprise around 2% of mouse RGCs. Projections of both primate and mouse orthologous types are overrepresented in the thalamus, which supplies the primary visual cortex. We suggest that midget RGCs are not primate innovations, but are descendants of evolutionarily ancient types that decreased in size and increased in number as primates evolved, thereby facilitating high visual acuity and increased cortical processing of visual information.


Assuntos
Evolução Biológica , Neurônios , Retina , Vertebrados , Visão Ocular , Animais , Humanos , Neurônios/classificação , Neurônios/citologia , Neurônios/fisiologia , Retina/citologia , Retina/fisiologia , Células Ganglionares da Retina/classificação , Análise da Expressão Gênica de Célula Única , Vertebrados/fisiologia , Visão Ocular/fisiologia , Especificidade da Espécie , Células Amácrinas/classificação , Células Fotorreceptoras/classificação , Células Ependimogliais/classificação , Células Bipolares da Retina/classificação , Percepção Visual
9.
Cell Rep ; 42(11): 113347, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37910503

RESUMO

Understanding the cell biological mechanisms that enable tumor cells to persist after therapy is necessary to improve the treatment of recurrent disease. Here, we demonstrate that transient receptor potential channel 6 (TRPC6), a channel that mediates calcium entry, contributes to the properties of breast cancer stem cells, including resistance to chemotherapy, and that tumor cells that persist after therapy are dependent on TRPC6. The mechanism involves the ability of TRPC6 to regulate integrin α6 mRNA splicing. Specifically, TRPC6-mediated calcium entry represses the epithelial splicing factor ESRP1 (epithelial splicing regulatory protein 1), which enables expression of the integrin α6B splice variant. TRPC6 and α6B function in tandem to facilitate stemness and persistence by activating TAZ and, consequently, repressing Myc. Therapeutic inhibition of TRPC6 sensitizes triple-negative breast cancer (TNBC) cells and tumors to chemotherapy by targeting the splicing of α6 integrin mRNA and inducing Myc. These data reveal a Ca2+-dependent mechanism of chemotherapy-induced persistence, which is amenable to therapy, that involves integrin mRNA splicing.


Assuntos
Antineoplásicos , Canais de Potencial de Receptor Transitório , Canais de Cálcio/metabolismo , Integrina alfa6 , Canal de Cátion TRPC6 , Cálcio/metabolismo , Canais de Cátion TRPC/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Invest Ophthalmol Vis Sci ; 64(14): 26, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975848

RESUMO

Purpose: To investigate compensatory gaze-scanning behaviors during street crossings by pedestrians with homonymous hemianopia (HH) and hemispatial neglect (HSN). Methods: Pedestrians with right homonymous hemianopia (RHH) and left homonymous hemianopia without (LHH) and with left spatial-neglect (LHSN) walked on city streets wearing a gaze-tracking system that also captured scene videos. Street-crossing instances were manually annotated, and horizontal gaze scan of magnitude ≥20° and scanning rates were compared within-subject, between the side of the hemifield loss (BlindSide) and the other side (SeeingSide). Proportion of instances with scans to both the left and the right side at nonsignalized crossings (indicative of safe scanning behavior) were compared among the three subject groups. Results: Data from 19 participants (6 LHH, 7 RHH, and 6 with mild [4] or moderate [2] LHSN), consisting of 521 street-crossing instances of a total duration of 201 minutes and 5375 gaze scans, were analyzed. The overall gaze magnitude (mean [95% confidence interval (CI)]) was significantly larger toward the BlindSide (40.4° [39.1°-41.9°]) than the SeeingSide (36° [34.8°-37.3°]; P < 0.001). The scanning rate (mean [95% CI] scans/min) toward the BlindSide (14 [12.5-15.6]) was significantly higher than the SeeingSide (11.5 [10.3°-12.9°]; P < 0.001). The scanning rate in the LHSN group (10.7 [8.9-12.8]) was significantly lower than the LHH group (14 [11.6-17.0]; P = 0.045). The proportion of nonsignalized crossings with scans to both sides was significantly lower in LHSN (58%; P = 0.039) and RHH (51%; P = 0.003) than LHH (75%) participants. Conclusions: All groups demonstrated compensatory scanning, making more gaze scans with larger magnitudes to the blind side. Mild to moderate LHSN adversely impacted the scanning rate.


Assuntos
Pedestres , Transtornos da Percepção , Humanos , Hemianopsia/diagnóstico , Campos Visuais
11.
Altern Ther Health Med ; 29(8): 478-481, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37883772

RESUMO

Introduction: Hair is regarded as an essential part of human identity, and losing it has a negative effect on many facets of one's quality of life. Alopecia areata (AA) is a chronic, non-scarring hair loss of the scalp or body hair. It is believed to be an autoimmune disorder where the body cannot recognize its own cells, resulting in the subsequent destruction of the hair follicles. The efficacy of the available treatment is not adequate and remission of hair follicles is unpredictable. However, individualized homoeopathy (iHOM) has shown great results in treating AA. Methods: At the Dermatological Department of D.Y. Patil Homoeopathic Medical College & Research Center, India, an 11-year-old female patient diagnosed with Alopecia areata was treated homeopathically from July 2021 to November 2021. During the follow-up visits, the outcome was assessed. To assess whether the changes were due to homoeopathic medicine, an assessment using the modified Naranjo criteria was performed. Results: Over an observation period of 5 months, beneficial result from iHOM medicine was seen, and so can be used by physicians in treating Alopecia Areata as a complementary health practice. Conclusion: Considering the multi-factorial etiology of Alopecia Areata, iHOM medicine and the auxillary line of treatment are effective in treating Alopecia Areata.


Assuntos
Alopecia em Áreas , Homeopatia , Criança , Feminino , Humanos , Alopecia em Áreas/tratamento farmacológico , Alopecia em Áreas/diagnóstico , Cabelo , Qualidade de Vida
12.
Cureus ; 15(8): e43009, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37674956

RESUMO

Introduction Musculoskeletal (MSK) well-being plays a crucial role in determining one's quality of life. Musculoskeletal Health Questionnaire (MSK-HQ) score is a tool recently developed by the Versus Arthritis group of Oxford University in English to measure MSK health. Marathi is a regional language in western India spoken by more than 100 million people. There is a scarcity of valid and reliable tools to measure MSK health in this language. Hence, we decided to cross-culturally adapt and translate MSK-HQ to Marathi. Method We translated MSK-HQ score to Marathi (MSK-HQ-Ma) as per the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guidelines. We tested its internal consistency, construct validity and reproducibility. It was compared with other health status scores EQ-5D-5L and overall health using the Visual Analogue Scale (VAS). Test-retest reliability was tested in those subjects who were having stable MSK health after two weeks. Results We recruited 158 consecutive subjects attending musculoskeletal clinics who had Marathi as their native language. Mean age was 44.8±17 years, females were 78 (49%). It showed good internal consistency (Cronbach's alpha = 0.95). For construct validity we found a strong correlation between MSK-HQ-Ma and EQ-5D-5L values (Spearman's r = 0.82, p<0.001). There was also a good correlation between MSK-HQ-Ma and overall health by VAS (Spearman's r = 0.76, p<0.001). An excellent test-retest reliability (Spearman's r = 0.94, p<0.001) was seen in 105 subjects who had stable MSK condition after two weeks of first appearance. Conclusion The MSK-HQ-Ma instrument has demonstrated good consistency, reliability and construct validity when evaluating the musculoskeletal health of individuals who can understand the Marathi language. Hence it can be used as a validated tool for the evaluation of musculoskeletal health in western India where Marathi is a commonly used language.

13.
ACS Omega ; 8(32): 29359-29373, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37599980

RESUMO

ß-Lactam antibiotics remain one of the most effective therapeutics to treat infections caused by Gram-negative bacteria (GNB). However, since ancient times, bacteria have developed multiple resistance mechanisms toward this class of antibiotics including overexpression of ß-lactamases, suppression of porins, outer membrane impermeability, overexpression of efflux pumps, and target modifications. To cope with these challenges and to extend the lifetime of existing ß-lactam antibiotics, ß-lactamase inhibitors are combined with ß-lactam antibiotics to prevent antibiotic inactivation by ß-lactamases. The combination therapy of an outer membrane permeabilizer with ß-lactam antibiotics is an alternative approach to overcoming bacterial resistance of ß-lactams in GNB. This approach is of particular interest for pathogens with highly impermeable outer membranes like Pseudomonas aeruginosa. Previous studies have shown that outer membrane permeabilizers can be designed by linking tobramycin and nebramine units together in the form of dimers or chimeras. In this study, we developed trimeric tobramycin and nebramine-based outer membrane permeabilizers presented on a central 1,3,5-triazine framework. The resultant trimers are capable of potentiating outer membrane-impermeable antibiotics but also ß-lactams and ß-lactam/ß-lactamase inhibitor combinations against resistant P. aeruginosa isolates. Furthermore, the microbiological susceptibility breakpoints of ceftazidime, aztreonam, and imipenem were reached by a triple combination consisting of an outer-membrane permeabilizer/ß-lactam/ß-lactamase inhibitor in ß-lactam-resistant P. aeruginosa isolates. Overall, our results indicate that trimeric tobramycins/nebramines can rescue clinically approved ß-lactams and ß-lactam/ß-lactamase inhibitor combinations from resistance.

14.
Access Microbiol ; 5(6)2023.
Artigo em Inglês | MEDLINE | ID: mdl-37424542

RESUMO

Bacteria resistant to antibiotics arguably pose the greatest threat to human health in the twenty-first century. One such bacterium that typifies antibiotic resistance is Acinetobacter baumannii . Frequently, hospital strains of A. baumannii display multidrug resistant (MDR) or extensively drug resistant (XDR) phenotypes, often requiring the use of last resort antibiotics for treatment. In addition to hospital settings, A. baumannii has been isolated from many highly divergent sources including wastewater treatment plant effluent, soil, and agricultural run-off with global distribution. However, such isolates remain poorly characterized. In this study, we characterized a strain of A. baumannii, AB341-IK15, isolated from bulk tank milk in Germany that demonstrated resistance to ceftazidime and intermediate resistance to ceftriaxone and piperacillin/tazobactam. Further genetic characterization identified an ADC-5 cephalosporinase, first incidence in an environmental isolate; and an OXA-408 oxacillinase that may contribute to this phenotype. Interestingly, AB341-IK15 is of a novel sequence type. This research underscores the importance of studying isolates of A. baumannii of non-clinical origin to understand the antibiotic resistance and virulence potential of environmental isolates of A. baumannii as well to understand the diversity of this species.

16.
Sci Transl Med ; 15(694): eade5855, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37134151

RESUMO

Prostate cancers are largely unresponsive to immune checkpoint inhibitors (ICIs), and there is strong evidence that programmed death-ligand 1 (PD-L1) expression itself must be inhibited to activate antitumor immunity. Here, we report that neuropilin-2 (NRP2), which functions as a vascular endothelial growth factor (VEGF) receptor on tumor cells, is an attractive target to activate antitumor immunity in prostate cancer because VEGF-NRP2 signaling sustains PD-L1 expression. NRP2 depletion increased T cell activation in vitro. In a syngeneic model of prostate cancer that is resistant to ICI, inhibition of the binding of VEGF to NRP2 using a mouse-specific anti-NRP2 monoclonal antibody (mAb) resulted in necrosis and tumor regression compared with both an anti-PD-L1 mAb and control immunoglobulin G. This therapy also decreased tumor PD-L1 expression and increased immune cell infiltration. We observed that the NRP2, VEGFA, and VEGFC genes are amplified in metastatic castration-resistant and neuroendocrine prostate cancer. We also found that individuals with NRP2High PD-L1High metastatic tumors had lower androgen receptor expression and higher neuroendocrine prostate cancer scores than other individuals with prostate cancer. In organoids derived from patients with neuroendocrine prostate cancer, therapeutic inhibition of VEGF binding to NRP2 using a high-affinity humanized mAb suitable for clinical use also diminished PD-L1 expression and caused a substantial increase in immune-mediated tumor cell killing, consistent with the animal studies. These findings provide justification for the initiation of clinical trials using this function-blocking NRP2 mAb in prostate cancer, especially for patients with aggressive disease.


Assuntos
Neoplasias da Próstata , Fator A de Crescimento do Endotélio Vascular , Masculino , Animais , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neuropilina-2/genética , Neuropilina-2/metabolismo , Transdução de Sinais , Antígeno B7-H1/genética , Neoplasias da Próstata/metabolismo
17.
Sci Transl Med ; 15(694): eadf1128, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37134152

RESUMO

Although blocking the binding of vascular endothelial growth factor (VEGF) to neuropilin-2 (NRP2) on tumor cells is a potential strategy to treat aggressive carcinomas, a lack of effective reagents that can be used clinically has hampered this potential therapy. Here, we describe the generation of a fully humanized, high-affinity monoclonal antibody (aNRP2-10) that specifically inhibits the binding of VEGF to NRP2, conferring antitumor activity without causing toxicity. Using triple-negative breast cancer as a model, we demonstrated that aNRP2-10 could be used to isolate cancer stem cells (CSCs) from heterogeneous tumor populations and inhibit CSC function and epithelial-to-mesenchymal transition. aNRP2-10 sensitized cell lines, organoids, and xenografts to chemotherapy and inhibited metastasis by promoting the differentiation of CSCs to a state that is more responsive to chemotherapy and less prone to metastasis. These data provide justification for the initiation of clinical trials designed to improve the response of patients with aggressive tumors to chemotherapy using this monoclonal antibody.


Assuntos
Neuropilina-2 , Neoplasias de Mama Triplo Negativas , Humanos , Neuropilina-2/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ligação Proteica , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/metabolismo , Linhagem Celular Tumoral , Neuropilina-1/metabolismo
18.
Front Plant Sci ; 14: 1151057, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123843

RESUMO

Two major future challenges are an increase in global earth temperature and a growing world population, which threaten agricultural productivity and nutritional food security. Underutilized crops have the potential to become future climate crops due to their high climate-resilience and nutritional quality. In this context, C4 pseudocereals such as grain amaranths are very important as C4 crops are more heat tolerant than C3 crops. However, the thermal sensitivity of grain amaranths remains unexplored. Here, Amaranthus hypochondriacus was exposed to heat stress at the vegetative and reproductive stages to capture heat stress and recovery responses. Heat Shock Factors (Hsfs) form the central module to impart heat tolerance, thus we sought to identify and characterize Hsf genes. Chlorophyll content and chlorophyll fluorescence (Fv/Fm) reduced significantly during heat stress, while malondialdehyde (MDA) content increased, suggesting that heat exposure caused stress in the plants. The genome-wide analysis led to the identification of thirteen AhHsfs, which were classified into A, B and C classes. Gene expression profiling at the tissue and developmental scales resolution under heat stress revealed the transient upregulation of most of the Hsfs in the leaf and inflorescence tissues, which reverted back to control levels at the recovery time point. However, a few Hsfs somewhat sustained their upregulation during recovery phase. The study reported the identification, physical location, gene/motif structure, promoter analysis and phylogenetic relationships of Hsfs in Amaranthus hypochondriacus. Also, the genes identified may be crucial for future gene functional studies and develop thermotolerant cultivars.

19.
Genes (Basel) ; 14(5)2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37239397

RESUMO

BACKGROUND: The high prevalence and rapid emergence of antibiotic resistance in high-risk Klebsiella pneumoniae (KP) ST147 clones is a global health concern and warrants molecular surveillance. METHODS: A pangenome analysis was performed using publicly available ST147 complete genomes. The characteristics and evolutionary relationships among ST147 members were investigated through a Bayesian phylogenetic analysis. RESULTS: The large number of accessory genes in the pangenome indicates genome plasticity and openness. Seventy-two antibiotic resistance genes were found to be linked with antibiotic inactivation, efflux, and target alteration. The exclusive detection of the blaOXA-232 gene within the ColKp3 plasmid of KP_SDL79 suggests its acquisition through horizontal gene transfer. The association of seventy-six virulence genes with the acrAB efflux pump, T6SS system and type I secretion system describes its pathogenicity. The presence of Tn6170, a putative Tn7-like transposon in KP_SDL79 with an insertion at the flanking region of the tnsB gene, establishes its transmission ability. The Bayesian phylogenetic analysis estimates ST147's initial divergence in 1951 and the most recent common ancestor for the entire KP population in 1621. CONCLUSIONS: Present study highlights the genetic diversity and evolutionary dynamics of high-risk clones of K. pneumoniae. Further inter-clonal diversity studies will help us understand its outbreak more precisely and pave the way for therapeutic interventions.


Assuntos
Infecções por Klebsiella , beta-Lactamases , Humanos , beta-Lactamases/genética , Klebsiella pneumoniae/genética , Filogenia , Teorema de Bayes , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/genética , Infecções por Klebsiella/tratamento farmacológico
20.
Artigo em Inglês | MEDLINE | ID: mdl-37030815

RESUMO

In volume visualization transfer functions are widely used for mapping voxel properties to color and opacity. Typically, volume density data are scalars which require simple 1D transfer functions to achieve this mapping. If the volume densities are vectors of three channels, one can straightforwardly map each channel to either red, green or blue, which requires a trivial extension of the 1D transfer function editor. We devise a new method that applies to volume data with more than three channels. These types of data often arise in scientific scanning applications, where the data are separated into spectral bands or chemical elements. Our method expands on prior work in which a multivariate information display, RadViz, was fused with a radial color map, in order to visualize multi-band 2D images. In this work, we extend this joint interface to blended volume rendering. The information display allows users to recognize the presence and value distribution of the multivariate voxels and the joint volume rendering display visualizes their spatial distribution. We design a set of operators and lenses that allow users to interactively control the mapping of the multivariate voxels to opacity and color. This enables users to isolate or emphasize volumetric structures with desired multivariate properties. Furthermore, it turns out that our method also enables more insightful displays even for RGB data. We demonstrate our method with three datasets obtained from spectral electron microscopy, high energy X-ray scanning, and atmospheric science.

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