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1.
Nat Immunol ; 25(8): 1411-1421, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38997431

RESUMO

A subset of individuals exposed to Mycobacterium tuberculosis (Mtb) that we refer to as 'resisters' (RSTR) show evidence of IFN-γ- T cell responses to Mtb-specific antigens despite serially negative results on clinical testing. Here we found that Mtb-specific T cells in RSTR were clonally expanded, confirming the priming of adaptive immune responses following Mtb exposure. RSTR CD4+ T cells showed enrichment of TH17 and regulatory T cell-like functional programs compared to Mtb-specific T cells from individuals with latent Mtb infection. Using public datasets, we showed that these TH17 cell-like functional programs were associated with lack of progression to active tuberculosis among South African adolescents with latent Mtb infection and with bacterial control in nonhuman primates. Our findings suggested that RSTR may successfully control Mtb following exposure and immune priming and established a set of T cell biomarkers to facilitate further study of this clinical phenotype.


Assuntos
Linfócitos T CD4-Positivos , Mycobacterium tuberculosis , Tuberculose , Mycobacterium tuberculosis/imunologia , Humanos , Animais , Adolescente , Tuberculose/imunologia , Tuberculose/microbiologia , Linfócitos T CD4-Positivos/imunologia , Células Th17/imunologia , Feminino , Macaca mulatta , Masculino , Fenótipo , Interferon gama/metabolismo , Interferon gama/imunologia , Antígenos de Bactérias/imunologia , Tuberculose Latente/imunologia , Tuberculose Latente/microbiologia , África do Sul , Adulto Jovem , Linfócitos T Reguladores/imunologia , Adulto
3.
Mol Ther ; 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369272

RESUMO

Acute myeloid leukemia (AML) is a lethal hematologic malignancy. Chemotherapy resistance results in a dismal survival rate of 1-2 years in older adults with AML. Therefore, novel therapies are urgently required. In this context, microRNA (miRNA)-based treatments remain an untapped strategy in AML. Using patient-derived specimens, we found increased inflammatory cytokines, including interleukin-6 (IL-6) in the serum of older adults with AML, and decreased miR-497-5p in CD34+ leukemic blasts. Target prediction revealed that miR-497-5p could directly target mitogen-activated protein kinase-1 (MAP2K1) mRNA to indirectly target cytokines and the JAK/STAT signaling pathway through the p38-MAPK signaling pathway, potentially inhibiting leukemic growth and overcoming chemoresistance from venetoclax. To improve miRNA delivery and minimize off-target effects, which represent key barriers to clinical translation, we developed liposomes for co-delivery of miR-497-5p and venetoclax. We decorated our liposomes with a peptide targeting CLL1, which is present on 92% of leukemia blasts while being absent in normal hematopoietic cells. This targeted approach demonstrated high efficacy in inhibiting AML growth in mice with minimal toxicity, as well as reduced exposure to chemoresistance. Our findings suggested that anti-CLL1-decorated, miR-497-5p, and venetoclax-loaded liposomes represent a promising novel miRNA-based therapeutic, which should be investigated further as a strategy to reduce venetoclax resistance in AML.

4.
Nucleic Acids Res ; 51(17): 9314-9336, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37439347

RESUMO

We have examined the roles of yeast mRNA decapping-activators Pat1 and Dhh1 in repressing the translation and abundance of specific mRNAs in nutrient-replete cells using ribosome profiling, RNA-Seq, CAGE analysis of capped mRNAs, RNA Polymerase II ChIP-Seq, and TMT-mass spectrometry of mutants lacking one or both factors. Although the Environmental Stress Response (ESR) is activated in dhh1Δ and pat1Δ mutants, hundreds of non-ESR transcripts are elevated in a manner indicating cumulative repression by Pat1 and Dhh1 in wild-type cells. These mRNAs show both reduced decapping and diminished transcription in the mutants, indicating that impaired mRNA turnover drives transcript derepression in cells lacking Dhh1 or Pat1. mRNA degradation stimulated by Dhh1/Pat1 is not dictated by poor translation nor enrichment for suboptimal codons. Pat1 and Dhh1 also collaborate to reduce translation and protein production from many mRNAs. Transcripts showing concerted translational repression by Pat1/Dhh1 include mRNAs involved in cell adhesion or utilization of the poor nitrogen source allantoin. Pat1/Dhh1 also repress numerous transcripts involved in respiration, catabolism of non-preferred carbon or nitrogen sources, or autophagy; and we obtained evidence for elevated respiration and autophagy in the mutants. Thus, Pat1 and Dhh1 function as post-transcriptional repressors of multiple pathways normally activated only during nutrient limitation.


Assuntos
Saccharomyces cerevisiae , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Nutrientes , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
5.
J Physiol ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39323077

RESUMO

Smooth muscle organs of the lower urinary tract comprise the bladder detrusor and urethral wall, which have a reciprocal contractile relationship during urine storage and micturition. As the bladder fills with urine, detrusor smooth muscle cells (DSMCs) remain relaxed to accommodate increases in intravesical pressure while urethral smooth muscle cells (USMCs) sustain tone to occlude the urethral orifice, preventing leakage. While neither organ displays coordinated regular contractions as occurs in small intestine, lymphatics or renal pelvis, they do exhibit patterns of rhythmicity at cellular and tissue levels. In rabbit and guinea-pig urethra, electrical slow waves are recorded from USMCs. This activity is linked to cells expressing vimentin, c-kit and Ca2+-activated Cl- channels, like interstitial cells of Cajal in the gastrointestinal tract. In mouse, USMCs are rhythmically active (firing propagating Ca2+ waves linked to contraction), and this cellular rhythmicity is asynchronous across tissues and summates to form tone. Experiments in mice have failed to demonstrate a voltage-dependent mechanism for regulating this rhythmicity or contractions in vitro, suggesting that urethral tone results from an intrinsic ability of USMCs to 'pace' their own Ca2+ mobilization pathways required for contraction. DSMCs exhibit spontaneous transient contractions, increases in intracellular Ca2+ and action potentials. Consistent across numerous species, including humans, this activity relies on voltage-dependent Ca2+ influx in DSMCs. While interstitial cells are present in the bladder, they do not 'pace' the organ in an excitatory manner. Instead, specialized cells (PDGFRα+ interstitial cells) may 'negatively pace' DSMCs to prevent bladder overexcitability.

6.
Biochem Biophys Res Commun ; 735: 150833, 2024 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-39423573

RESUMO

Plastics and plasticizers accumulate in the ecological niches affecting biodiversity, and human and environmental health. Bacteria degrading polyethylene terephthalate (PET) were screened and PETases involved in PET degradation were characterized. Here, we identified a carboxylesterase Dkca1 of 48.44 kDa molecular mass from Dietzia kunjamensis IITR165 shown to degrade amorphous PET film into bis(2-hydroxyethyl) terephthalate (BHET) and terephthalic acid (TPA) formed 64.35 µM and 35.26 µM, respectively within 96 h at 37 °C as revealed by LC-MS analysis showed significant PET hydrolase activity similar to reported PETases. SEM analysis confirms the surface erosion as cavities and holes. Dkca1 also hydrolysed BHET and dibutyl phthalate (DBP) at a concentration of 1 mM within 3 h indicating its versatility. Fluorescence quenching shows Dkca1 protein has a maximum affinity (Kd) towards BHET (86.55 µM) than DBP (134.2 µM). The protein demonstrated high stability under temperatures above 40 °C and at the pH range of 6.0-9.0. Moreover, Amino acid composition showed that the Dkca1 enzyme belongs to family VII carboxylesterase containing conserved catalytic triad of Ser183-Glu289-His378 with pentapeptide motif GXSAG and an oxyanion hole H103GGG106, sharing 37.47 % and 32.44 % similarity with a PET hydrolase TfCa from Thermobifida fusca and PAE hydrolase CarEW from Bacillus sp. K91, respectively. A docking study revealed that ligand PET, BHET, and DBP showed favourable binding in the catalytic pocket of the Dkca1 protein.

7.
Nat Mater ; 22(3): 380-390, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36717665

RESUMO

The ideal vaccine against viruses such as influenza and SARS-CoV-2 must provide a robust, durable and broad immune protection against multiple viral variants. However, antibody responses to current vaccines often lack robust cross-reactivity. Here we describe a polymeric Toll-like receptor 7 agonist nanoparticle (TLR7-NP) adjuvant, which enhances lymph node targeting, and leads to persistent activation of immune cells and broad immune responses. When mixed with alum-adsorbed antigens, this TLR7-NP adjuvant elicits cross-reactive antibodies for both dominant and subdominant epitopes and antigen-specific CD8+ T-cell responses in mice. This TLR7-NP-adjuvanted influenza subunit vaccine successfully protects mice against viral challenge of a different strain. This strategy also enhances the antibody response to a SARS-CoV-2 subunit vaccine against multiple viral variants that have emerged. Moreover, this TLR7-NP augments antigen-specific responses in human tonsil organoids. Overall, we describe a nanoparticle adjuvant to improve immune responses to viral antigens, with promising implications for developing broadly protective vaccines.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Nanopartículas , Animais , Camundongos , Humanos , Influenza Humana/prevenção & controle , Receptor 7 Toll-Like/genética , SARS-CoV-2/genética , COVID-19/prevenção & controle , Adjuvantes Imunológicos/farmacologia , Imunidade , Vacinas de Subunidades Antigênicas
8.
J Am Acad Dermatol ; 90(3): 545-551, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37949119

RESUMO

BACKGROUND: Metastatic basal cell carcinoma (mBCC) is rare and there are limited data regarding patient and tumor risk factors, optimal treatments, and disease prognosis. OBJECTIVE: To assess patient and tumor characteristics, therapeutics, and outcomes of mBCC stratified by location of metastasis. METHODS: Retrospective cohort study of 53 patients with mBCC treated at 4 large academic centers in Boston, Massachusetts; Philadelphia, Pennsylvania; and Cleveland, Ohio between January 1, 2005 and December 31, 2021. RESULTS: A total of 53 patients with mBCC were identified across 4 centers, 22 (42%) of whom had mBCC with spread limited to lymph nodes and 31 (58%) patients with distant organ spread (with or without lymph node involvement). Overall, half (n = 11) of patients with nodal metastasis achieved complete remission of disease, compared with just 1 (3%) patient with distant metastasis. The 5-year survival for nodal and distant metastatic patients was 89.3% and 61.0%, respectively. LIMITATIONS: Small sample size due to disease rarity. CONCLUSIONS AND RELEVANCE: Patients with nodal disease are more likely to have disease remission whereas patients with distant metastasis are more likely to have persistent disease and die from their disease. However, 5-year survival rates exceed 50%, even for stage IV disease.


Assuntos
Carcinoma Basocelular , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/patologia , Estudos Retrospectivos , Carcinoma Basocelular/patologia , Prognóstico , Linfonodos/patologia , Fatores de Risco , Philadelphia
9.
Prenat Diagn ; 44(6-7): 876-878, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38752660

RESUMO

Fetal pericardial teratomas are rare. They present with pericardial effusion and hydrops. The definitive management is postnatal resection of the tumor. The exact antenatal management is not known due to its rarity. We present a case of fetal pericardial teratoma with pericardial tamponade. Pericardiocentesis performed at 31 weeks significantly relieved the venous compression, leading to resolution of hydrops and prolonging the gestational age for the definitive management.


Assuntos
Neoplasias Cardíacas , Pericardiocentese , Teratoma , Humanos , Teratoma/cirurgia , Teratoma/complicações , Teratoma/diagnóstico , Teratoma/diagnóstico por imagem , Pericardiocentese/métodos , Feminino , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/cirurgia , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/diagnóstico , Gravidez , Adulto , Ultrassonografia Pré-Natal , Derrame Pericárdico/cirurgia , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/etiologia , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Tamponamento Cardíaco/diagnóstico , Hidropisia Fetal/etiologia , Hidropisia Fetal/diagnóstico , Hidropisia Fetal/cirurgia , Doenças Fetais/cirurgia
10.
Dermatol Surg ; 50(7): 611-615, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38700380

RESUMO

BACKGROUND: Risk stratification can identify individuals in primary care settings who are at increased risk of developing melanoma. OBJECTIVE: Converting and implementing a validated risk stratification tool as a patient self-administered tablet-based survey. METHODS: Mackie risk stratification tool was transformed into a patient questionnaire. The questionnaire was completed in academic dermatologist practices by patients and dermatologists and revised to optimize sensitivity and specificity using physician assessment as gold standard. The optimized survey was administered before routine primary care visits during 2019 to 2021. High-risk patients were referred to dermatology. The number needed to screen (NNS), sensitivity, specificity, positive predictive value, and negative predictive value to identify a melanoma were calculated. RESULTS: Of the 7,893 respondents, 5,842 (74%) and 2,051 (26%) patients were categorized as low-risk and high-risk population, respectively. The NNS to identify 1 melanoma was 64 in the high-risk population. CONCLUSION: Incorporating self-administered patient-risk stratification tools in primary care settings can identify high-risk individuals for targeted melanoma screening. Further studies are needed to optimize specificity and sensitivity in more targeted populations.


Assuntos
Detecção Precoce de Câncer , Melanoma , Atenção Primária à Saúde , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Projetos Piloto , Medição de Risco/métodos , Feminino , Neoplasias Cutâneas/diagnóstico , Masculino , Detecção Precoce de Câncer/métodos , Pessoa de Meia-Idade , Adulto , Inquéritos e Questionários/estatística & dados numéricos , Idoso , Sensibilidade e Especificidade , Computadores de Mão
11.
Am J Perinatol ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38768642

RESUMO

OBJECTIVE: This study aimed to identify factors associated with refractory severe hypertension that does not resolve after an initial dose of antihypertensive medication in patients with preeclampsia. STUDY DESIGN: This was a retrospective study of all pregnant and postpartum individuals with a diagnosis of preeclampsia, superimposed preeclampsia, HELLP (hemolysis, elevated liver enzymes, low platelet) syndrome, or eclampsia who delivered at 22 weeks or greater at a single academic institution from 2010 to 2020. Inclusion criteria were patients with preeclampsia who developed severe hypertension (systolic pressure ≥160 mm Hg or diastolic pressure ≥110 mm Hg) and received antihypertensive medications for acute severe hypertension. We defined refractory severe hypertension as a systolic blood pressure of ≥160 mm Hg or a diastolic blood pressure of ≥110 mm Hg that did not improve after receiving the initial treatment. To evaluate for factors associated with refractory severe hypertension, we developed multivariable modified Poisson regression using all variables with p-value <0.1 on bivariable analysis and calculated adjusted relative risks (aRRs) with 95% confidence intervals (95% CIs). RESULTS: Of 850, 386 (45.4%) had refractory severe hypertension and 464 (54.6%) responded to the initial antihypertensive medications. Factors associated with refractory severe hypertension included higher body mass index (BMI), chronic hypertension, and higher systolic pressure. Every 5 kg/m2 increase in BMI was associated with a 7% increased risk of refractory severe hypertension (aRR = 1.07; 95% CI: 1.02-1.12). Every 10 mm Hg increase in systolic blood pressure was associated with a 10% increased risk of refractory severe hypertension (aRR = 1.10; 95% CI: 1.04-1.17). Chronic hypertension was associated with a 25% increased risk of refractory severe hypertension (aRR = 1.25; 95% CI: 1.01-1.56) in the diastolic pressure model. CONCLUSION: Refractory severe hypertension was associated with elevated BMI, chronic hypertension, and higher systolic blood pressure. KEY POINTS: · Risk factors for refractory severe hypertension are not well-known.. · Almost half of the patients had refractory severe hypertension.. · Higher BMI, chronic hypertension, and higher systolic pressure were the risk factors.. · These patients would require closer follow-up and prompt response to vital signs..

12.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39273596

RESUMO

Staphylococcus aureus infections present a significant threat to the global healthcare system. The increasing resistance to existing antibiotics and their limited efficacy underscores the urgent need to identify new antibacterial agents with low toxicity to effectively combat various S. aureus infections. Hence, in this study, we have screened T-muurolol for possible interactions with several S. aureus-specific bacterial proteins to establish its potential as an alternative antibacterial agent. Based on its binding affinity and interactions with amino acids, T-muurolol was identified as a potential inhibitor of S. aureus lipase, dihydrofolate reductase, penicillin-binding protein 2a, D-Ala:D-Ala ligase, and ribosome protection proteins tetracycline resistance determinant (RPP TetM), which indicates its potentiality against S. aureus and its multi-drug-resistant strains. Also, T-muurolol exhibited good antioxidant and anti-inflammatory activity by showing strong binding interactions with flavin adenine dinucleotide (FAD)-dependent nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, and cyclooxygenase-2. Consequently, molecular dynamics (MD) simulation and recalculating binding free energies elucidated its binding interaction stability with targeted proteins. Furthermore, quantum chemical structure analysis based on density functional theory (DFT) depicted a higher energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital (EHOMO-LUMO) with a lower chemical potential index, and moderate electrophilicity suggests its chemical hardness and stability and less polarizability and reactivity. Additionally, pharmacological parameters based on ADMET, Lipinski's rules, and bioactivity score validated it as a promising drug candidate with high activity toward ion channel modulators, nuclear receptor ligands, and enzyme inhibitors. In conclusion, the current findings suggest T-muurolol as a promising alternative antibacterial agent that might be a potential phytochemical-based drug against S. aureus. This study also suggests further clinical research before human application.


Assuntos
Antibacterianos , Descoberta de Drogas , Compostos Fitoquímicos , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Descoberta de Drogas/métodos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Simulação por Computador , Humanos , Antioxidantes/farmacologia , Antioxidantes/química
13.
Int Ophthalmol ; 44(1): 231, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822988

RESUMO

PURPOSE: To analyze the intraoperative challenges of cataract surgery in children, following glaucoma filtering surgery. METHODS: This was a retrospective study to analyze intra-op challenges and outcomes of pediatric cataract surgery in post-glaucoma filtration surgery eyes, between January 2007 and December 2019. RESULTS: We included 20 eyes of 16 children. The most common glaucoma surgery performed was trabeculectomy and trabeculotomy (14 eyes). The median age at the time of cataract surgery was 74.5 months. The most common cataract surgery performed was lens aspiration with posterior chamber intraocular lens implantation (LA + PCIOL) (9/20). The most common intraoperative challenge faced was difficulty in capsulorrhexis (ten eyes), followed by extension of primary posterior capsulotomy (six eyes). At the final follow up eight eyes had improvement in visual acuity, five eyes had stable visual acuity and five eyes had a drop in visual acuity. In 12/20 eyes IOL was implanted, nine eyes in-the-bag and three eyes had in ciliary sulcus. None of the IOLs in the bag had decentration of IOL. The median postoperative IOP (p = 0.12) and median number of postoperative AGM (p = 0.13) at 2 years remained stable compared to the preoperative values. The IOP remained well controlled in 4 eyes without anti-glaucoma medications and in 14 eyes with anti-glaucoma medications and none needed additional surgery for IOP control. Two eyes developed retinal detachment postoperatively. CONCLUSION: Cataract surgery in pediatric eyes with prior glaucoma surgeries, have challenges with capsulorrhexis and IOL stability. The visual outcomes were reasonably good so was the IOP control.


Assuntos
Extração de Catarata , Catarata , Glaucoma , Pressão Intraocular , Acuidade Visual , Humanos , Estudos Retrospectivos , Masculino , Feminino , Extração de Catarata/métodos , Extração de Catarata/efeitos adversos , Criança , Pré-Escolar , Pressão Intraocular/fisiologia , Glaucoma/cirurgia , Glaucoma/fisiopatologia , Catarata/complicações , Cirurgia Filtrante/métodos , Seguimentos , Resultado do Tratamento , Adolescente , Complicações Intraoperatórias , Lactente , Trabeculectomia/métodos , Implante de Lente Intraocular/métodos
14.
Indian J Plast Surg ; 57(3): 216-222, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39139693

RESUMO

Background Kite string injuries (manja cut injuries), particularly those caused by Chinese manja, are new culprit of emergencies especially in the month of January in Maharashtra region. These injuries commonly affect the neck, face, hands, and legs, especially among individuals traveling on two wheelers. The visibility challenge, where the kite's thread is difficult to see, further exacerbates the risk. Materials and Methods We have studied 10 cases of manja cut injuries presented to a tertiary care center in Nagpur during the last 2 years. Result A total of 10 patients reported kite string-related injuries to our department over a period of 2 years. All patients were male. The majority of patients presented in the younger age group with the mean age of presentation was 25 years. Majority of the patients had injuries in zone 2 of the hand. Conclusion Kite flying is a traditional festival celebrated in the month of January in Gujarat and Maharashtra for years. However, the introduction of Chinese or nylon manja has led to serious injuries and fate, affecting not only kite flyers but also bystanders, animals, and birds. This study seeks to highlight the harmful consequences of Chinese manja and deceptive appearance of manja giving false impression of simple lacerated wound which could be just a tip of the iceberg.

15.
J Gen Virol ; 104(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37326617

RESUMO

Geminivirus-betasatellite disease complexes are an epidemic threat to the majority of economically important crops across the world. Plant virus satellites including betasatellites are maintained by their associated helper virus. Geminivirus-betasatellites influence viral pathogenesis by substantially increasing or decreasing their helper virus accumulation. In the present study, we attempted to understand the mechanistic details of the geminivirus-betasatellite interaction. Here, we used tomato leaf curl Gujarat virus (ToLCGV) and tomato leaf curl Patna betasatellite (ToLCPaB) as a model system. This study reveals that ToLCGV can efficiently trans-replicate ToLCPaB in Nicotiana benthamiana plants, but ToLCPaB greatly reduced the accumulation of its helper virus DNA. For the first time, we have identified that the ToLCPaB-encoded ßC1 protein is able to interact with ToLCGV-encoded replication initiator protein (Rep). In addition, we demonstrate that the C-terminal region of ßC1 interacts with the C-terminus of Rep (RepC) protein. Our previous study had established that ßC1 proteins encoded by diverse betasatellites possess a novel ATP hydrolysis activity and the conserved lysine/arginine residues at positions 49 and 91 are necessary for this function. Here, we show that mutating lysine at positions 49 to alanine of ßC1 (ßC1K49A) protein did not affect its ability to interact with RepC protein. Biochemical studies performed with ATP hydrolysis activity-deficient K49A mutated ßC1 (ßC1K49A) and RepC proteins revealed that Rep-ßC1 interaction interferes with the ATP hydrolysis activity of Rep protein. Further, we demonstrate that ßC1 protein is able to interact with D227A and D289A mutated RepC proteins but not with D262A, K272A or D286A mutated RepC proteins, suggesting that the ßC1-interacting region of Rep protein encompasses its Walker-B and B' motifs. The results of docking studies supported that the ßC1-interacting region of Rep protein encompasses its motifs associated with ATP binding and ATP hydrolysis activities. Docking studies also provided evidence that the Rep-ßC1 interaction interferes with the ATP binding activity of Rep protein. Together, our findings suggest that ßC1 protein regulates helper virus accumulation by interfering with the ATP hydrolysis activity of helper virus Rep protein.


Assuntos
Begomovirus , Geminiviridae , Geminiviridae/genética , Vírus Auxiliares , Lisina/metabolismo , Hidrólise , Proteínas Virais/genética , Proteínas Virais/metabolismo , Begomovirus/genética , Trifosfato de Adenosina/metabolismo , Doenças das Plantas , Nicotiana
16.
Reproduction ; 165(1): 79-91, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36215093

RESUMO

In brief: Oocyte quality remains the most important and unsolved issue in reproduction. Our data show that multidrug resistance transporters and oocyte mitochondria are involved in determining oocyte quality in a mouse model. Abstract: Multidrug resistance transporter-1 (MDR-1) is a transmembrane ATP-dependent effluxer present in organs that transport a variety of xenobiotics and by-products. Previous findings by our group demonstrated that this transporter is also present in the oocyte mitochondrial membrane and that its mutation led to abnormal mitochondrial homeostasis. Considering the importance of these organelles in the female gamete, we assessed the impact of MDR-1 dysfunction on mouse oocyte quality, with a particular focus on the meiotic spindle organization, aneuploidies, Ca2+ homeostasis, ATP production and mtDNA mutations. Our results demonstrate that young Mdr1a mutant mice produce oocytes characterized by lower quality, with a significant delay in the germinal vesicle to germinal vesicle breakdown transition, an increased percentage of symmetric divisions, chromosome misalignments and a severely altered meiotic spindle shape compared to the wild types. Mutant oocytes exhibit 7000 more SNPs in the exomic DNA and twice the amount of mitochondrial DNA (mtDNA) SNPs compared to the wild-type ones. Ca2+ analysis revealed the inability of MDR-1 mutant oocytes to manage Ca2+ storage content and oscillations in response to several stimuli, and ATP quantification shows that mutant oocytes trend toward lower ATP levels compared to wild types. Finally, 1-year-old mutant ovaries express a lower amount of SIRT1, SIRT3, SIRT5, SIRT6 and SIRT7 compared to wild-type levels. These results together emphasize the importance of MDR-1 in mitochondrial physiology and highlight the influence of MDR-1 on oocyte quality and ovarian aging.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Cálcio , Meiose , Oócitos , Sirtuínas , Animais , Feminino , Camundongos , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , DNA Mitocondrial/genética , Resistência a Múltiplos Medicamentos , Homeostase , Oócitos/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismo , Fuso Acromático/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo
17.
J Gen Intern Med ; 38(1): 21-29, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35641722

RESUMO

BACKGROUND: Inequitable follow-up of abnormal cancer screening tests may contribute to racial/ethnic disparities in colon and breast cancer outcomes. However, few multi-site studies have examined follow-up of abnormal cancer screening tests and it is unknown if racial/ethnic disparities exist. OBJECTIVE: This report describes patterns of performance on follow-up of abnormal colon and breast cancer screening tests and explores the extent to which racial/ethnic disparities exist in public hospital systems. DESIGN: We conducted a retrospective cohort study using data from five California public hospital systems. We used multivariable robust Poisson regression analyses to examine whether patient-level factors or site predicted receipt of follow-up test. MAIN MEASURES: Using data from five public hospital systems between July 2015 and June 2017, we assessed follow-up of two screening results: (1) colonoscopy after positive fecal immunochemical tests (FIT) and (2) tissue biopsy within 21 days after a BIRADS 4/5 mammogram. KEY RESULTS: Of 4132 abnormal FITs, 1736 (42%) received a follow-up colonoscopy. Older age, Medicaid insurance, lack of insurance, English language, and site were negatively associated with follow-up colonoscopy, while Hispanic ethnicity and Asian race were positively associated with follow-up colonoscopy. Of 1702 BIRADS 4/5 mammograms, 1082 (64%) received a timely biopsy; only site was associated with timely follow-up biopsy. CONCLUSION: Despite the vulnerabilities of public-hospital-system patients, follow-up of abnormal cancer screening tests occurs at rates similar to that of patients in other healthcare settings, with colon cancer screening test follow-up occurring at lower rates than follow-up of breast cancer screening tests. Site-level factors have larger, more consistent impact on follow-up rates than patient sociodemographic traits. Resources are needed to identify health system-level factors, such as test follow-up processes or data infrastructure, that improve abnormal cancer screening test follow-up so that effective health system-level interventions can be evaluated and disseminated.


Assuntos
Neoplasias da Mama , Neoplasias Colorretais , Humanos , Feminino , Estudos Retrospectivos , Detecção Precoce de Câncer , Seguimentos , Neoplasias da Mama/diagnóstico , Colonoscopia , California/epidemiologia , Neoplasias Colorretais/diagnóstico
18.
Arch Virol ; 168(7): 196, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37386317

RESUMO

Geminiviruses have mastered plant cell modulation and immune invasion to ensue prolific infection. Encoding a relatively small number of multifunctional proteins, geminiviruses rely on satellites to efficiently re-wire plant immunity, thereby fostering virulence. Among the known satellites, betasatellites have been the most extensively investigated. They contribute significantly to virulence, enhance virus accumulation, and induce disease symptoms. To date, only two betasatellite proteins, ßC1, and ßV1, have been shown to play a crucial role in virus infection. In this review, we offer an overview of plant responses to betasatellites and counter-defense strategies deployed by betasatellites to overcome those responses.


Assuntos
Geminiviridae , Geminiviridae/genética , Células Vegetais , Imunidade Vegetal/genética , Virulência
19.
Arch Toxicol ; 97(4): 963-979, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36878992

RESUMO

The use of nanomaterials in medicine depends largely on nanotoxicological evaluation in order to ensure safe application on living organisms. Artificial intelligence (AI) and machine learning (MI) can be used to analyze and interpret large amounts of data in the field of toxicology, such as data from toxicological databases and high-content image-based screening data. Physiologically based pharmacokinetic (PBPK) models and nano-quantitative structure-activity relationship (QSAR) models can be used to predict the behavior and toxic effects of nanomaterials, respectively. PBPK and Nano-QSAR are prominent ML tool for harmful event analysis that is used to understand the mechanisms by which chemical compounds can cause toxic effects, while toxicogenomics is the study of the genetic basis of toxic responses in living organisms. Despite the potential of these methods, there are still many challenges and uncertainties that need to be addressed in the field. In this review, we provide an overview of artificial intelligence (AI) and machine learning (ML) techniques in nanomedicine and nanotoxicology to better understand the potential toxic effects of these materials at the nanoscale.


Assuntos
Inteligência Artificial , Nanoestruturas , Nanomedicina , Aprendizado de Máquina , Nanoestruturas/toxicidade
20.
Environ Monit Assess ; 195(8): 985, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488362

RESUMO

Planorbella trivolvis (ramshorn snail) is one of India's most extensively sold exotic aquarium pet snails. The unintentional or deliberate release of P. trivolvis may result in the colonisation and establishment as an invasive snail in freshwater ecosystems. However, the successful invasion of P. trivolvis will depend on several abiotic and biotic factors of the concerned freshwater ecosystem. We have assessed the possibility of overcoming the opposing factors in P. trivolvis invasion through laboratory-based experiments and examined the effects of household-derived pollutants on egg hatchability, adult survivability and fecundity, and temperature (15 to 35 °C) on growth, sexual maturity, and reproduction. Additionally, we have evaluated the potential of native predators as biotic resistance to invasion by prey-choice experiment. The results indicated that egg hatchability, adult survivability, and fecundity were reduced with increasing pollutant concentration. However, the same traits did not differ from a native freshwater snail, Indoplanorbis exustus. The fecundity of P. trivolvis increased with increasing body size, but no considerable differences at different temperature levels suggest a wide range of adaptation to temperature. Faster growth and the requirement of comparatively few days to attain sexual maturity were observed in the higher temperatures. The native predators, Glossiphonia weberi and Diplonychus rusticus, avoided P. trivolvis as prey over the alternative prey snails in most instances, suggesting the masking of biotic resistance against the colonisation. Our observations indicate that the chance dispersal of P. trivolvis from household or commercial aquaria may lead to a possible invasion of freshwater ecosystems under suitable conditions.


Assuntos
Ecossistema , Poluentes Ambientais , Animais , Monitoramento Ambiental , Índia , Caramujos
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