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1.
Proc Natl Acad Sci U S A ; 119(18): e2118465119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35486698

RESUMO

The GroEL/ES chaperonin cavity surface charge properties, especially the negative charges, play an important role in its capacity to assist intracavity protein folding. Remarkably, the larger fraction of GroEL/ES negative charges are not conserved among different bacterial species, resulting in a large variation in negative-charge density in the GroEL/ES cavity across prokaryotes. Intriguingly, eukaryotic GroEL/ES homologs have the lowest negative-charge density in the chaperonin cavity. This prompted us to investigate if GroEL's chaperoning mechanism changed during evolution. Using a model in vivo GroEL/ES substrate, we show that the ability of GroEL/ES to buffer entropic traps in the folding pathway of its substrate was partially dependent upon the negative-charge density inside its cavity. While this activity of GroEL/ES was found to be essential for Escherichia coli, it has been perfected in some organisms and diminished in others. However, irrespective of their charges, all the tested homologs retained their ability to regulate polypeptide chain collapse and remove enthalpic traps from folding pathways. The ability of these GroEL/ES homologs to buffer mutational variations in a model substrate correlated with their negative-charge density. Thus, Hsp60/10 chaperonins in different organisms may have changed to accommodate a different spectrum of mutations on their substrates.


Assuntos
Chaperonina 60 , Dobramento de Proteína , Chaperonina 60/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Chaperonas Moleculares/metabolismo , Peptídeos/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-38321360

RESUMO

OBJECTIVES: There is an unmet need to develop patient-reported outcomes (PRO) measures for Idiopathic Inflammatory Myopathies (IIM). To investigate the feasibility, compliance, and psychometric properties of NIH's Patient-Reported Outcomes Measurement Information System (PROMIS) physical function-20 (PF-20) in a large U.S. IIM population. METHODS: "Myositis Patient Centered Tele-Research" (My PACER) is a multicentre prospective observational study of IIM patients, competitively recruited through traditional in-person clinic visits (Center-Based Cohort [CBC]), and remotely using smartphone and web-based technology (Tele-Research Cohort [TRC]). The CBC was further randomly divided (1:1 ratio) into a traditional local sub-cohort, and a remote sub-cohort. Data collected included PRO and other patient self-assessments monthly for 6 months. Clinician-reported outcomes were obtained at baseline and 6 months. RESULTS: 120 IIM patients were enrolled (82 TRC/38 CBC, mean age 55 ± 13.4, 75% females, 81% Caucasians), with similar demographics and mean PROMIS PF-20 score between cohorts. The PROMIS PF-20 score was not associated with age, sex or race. The compliance and completion rates were similar between TRC and CBC as well as sub-cohorts. PROMIS PF-20 showed strong test-retest reliability at 1 month. PROMIS PF-20 was significantly associated with all core set measures except extra-muscular global and CK, as well as with most of symptoms, function and physical activity measures. PROMIS PF-20 illustrated concordant change with myositis response criteria and patient assessment, with a large effect size. CONCLUSIONS: PROMIS PF-20 demonstrates favorable psychometric properties including reliability, validity and responsiveness in a large cohort of myositis patients, with similar adherence in local or remotely enrolled patients.

3.
Naturwissenschaften ; 111(1): 9, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342817

RESUMO

This article presents an attempt to discriminate between human male and female hair samples using a single strand of scalp hair. The methodology involves the non-destructive application of ATR-FTIR spectroscopy coupled with chemometric analysis. A total of 96 hair samples, evenly distributed between 48 male and 48 female volunteers from India, were collected. Spectral analysis revealed subtle differences between the two groups, and reliance on visual interpretation might introduce biasness. To avoid subjective biases, chemometric techniques such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) were employed for enhanced data visualization and separation. PCA results revealed that the first 10 principal components accounted for 93% of the total variance, with three significant PCs. The PLS-DA model demonstrated a remarkable sensitivity and specificity in sex discrimination from hair samples, establishing its efficacy as a robust classification tool. Furthermore, the proposed model exhibited 100% accuracy in predicting unknown samples, underscoring its potential applicability in real-world scenarios. These outcomes affirm the viability of our approach for non-invasive classification of human male and female hair based on single-strand scalp hair analysis.


Assuntos
Quimiometria , Cabelo , Humanos , Masculino , Feminino , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Discriminante , Cabelo/química , Análise de Componente Principal , Proteínas Mutadas de Ataxia Telangiectasia/análise
4.
Immunol Invest ; 53(3): 295-347, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38206610

RESUMO

Respiratory diseases (RD) are a group of common ailments with a rapidly increasing global prevalence, posing a significant threat to humanity, especially the elderly population, and imposing a substantial burden on society and the economy. RD represents an unmet medical need that requires the development of viable pharmacotherapies. While various promising strategies have been devised to advance potential treatments for RD, their implementation has been hindered by difficulties in drug delivery, particularly in critically ill patients. Nanotechnology offers innovative solutions for delivering medications to the inflamed organ sites, such as the lungs. Although this approach is enticing, delivering nanomedicine to the lungs presents complex challenges that require sophisticated techniques. In this context, we review the potential of novel nanomedicine-based immunomodulatory strategies that could offer therapeutic benefits in managing this pressing health condition.


Assuntos
Nanopartículas , Doenças Respiratórias , Idoso , Humanos , Nanomedicina/métodos , Sistemas de Liberação de Medicamentos/métodos , Imunomodulação , Pulmão
5.
J Cell Physiol ; 238(7): 1530-1541, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37098757

RESUMO

Binding of lipopolysaccharide (LPS) to CD14 is required for its cellular effects via TLR4. A role of LPS/TLR4-mediated signaling in activated hepatic stellate cells (aHSCs), the major fibrogenic cells, in liver fibrosis has been reported. We investigated effects of LPS on carbon tetrachloride (CCl4)-induced fibrosis in CD14-knockout (KO) mice in vivo, and culture-activated HSCs in vitro. CCl4 (biweekly; 4 weeks)-treated wild type (WT) and CD14-KO mice were challenged with single LPS administration for 24 h. Liver injury, inflammation and fibrosis were determined. Culture-activated HSCs from WT or CD14-KO mice were stimulated with LPS. Parameters of fibrogenic activity (expression of collagen1a1 [Col1a1], α-smooth muscle actin [αSMA] and TGFß1) and inflammatory cytokines/chemokines were measured. CCl4 treatment caused similar liver injury and fibrosis in WT and CD14-KO mice. LPS increased liver injury and inflammation similarly in CCl4-treated WT and CD14-KO mice, but downregulated Timp1 and upregulated Mmp13. LPS elicited similar NFκB activation and inflammatory response in WT and CD14-KO aHSCs. LPS similarly downregulated Acta2 (encodes αSMA), Pdgfrb, Col1a1 and Mmp13 expression but did not affect Timp1 expression in WT and CD14-KO aHSCs. LPS did not alter Tgfb1 but increased expression of decorin (Dcn) (inhibitor of TGFß1) expression in WT and CD14-KO aHSCs. The results indicate that the effects of LPS on HSCs are CD14-independent, and CD14 is not required for hepatic fibrosis. LPS-induced down-modulation of fibrogenic markers in aHSCs is also CD14-independent.


Assuntos
Tetracloreto de Carbono , Receptores de Lipopolissacarídeos , Lipopolissacarídeos , Animais , Camundongos , Tetracloreto de Carbono/efeitos adversos , Células Estreladas do Fígado/metabolismo , Inflamação/patologia , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 4 Toll-Like/metabolismo
6.
Am J Pathol ; 192(3): 518-535, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34954210

RESUMO

Acetaminophen (APAP)-induced liver injury is influenced by inflammatory Gram-negative bacterial endotoxin [lipopolysaccharide (LPS)], mechanisms of which are not completely understood. Because LPS-stimulated perisinusoidal hepatic stellate cells (HSCs) produce cytokines that affect survival of hepatocytes, this study investigated their role in APAP-induced liver injury. Fed (nonstarved) rats were administered 5 mg/kg LPS or phosphate-buffered saline (PBS) vehicle, followed by 200 mg/kg APAP or PBS an hour later, and euthanized at 6 hours. Control rats received PBS at both time points. Both LPS and APAP caused mild hepatocyte injury (apoptosis), as assessed by histopathology, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining, and caspase-3 activation. The liver injury was augmented in rats administered LPS + APAP, in association with increased nuclear translocation of interferon-regulatory factor-1 (IRF1). In vitro, APAP augmented LPS/HSC-conditioned medium-induced inhibition of DNA and protein synthesis, apoptosis, and nuclear IRF1 in hepatocytes. LPS-stimulated HSCs produced interferon-ß (IFN-ß), and LPS/HSC + APAP-induced hepatocyte apoptosis was inhibited by anti-IFN-ß antibody. Finally, HSC-depleted mice produced significantly lower IFN-ß and tumor necrosis factor-α, exhibited less oxidative stress, and were protected from excessive injury due to high APAP dose (600 mg/kg), as well as LPS (5 mg/kg overnight) followed by APAP. In co-culture with or without LPS, HSCs increased expression of proinflammatory cytokines by Kupffer cells. These results suggest that HSCs play a critical role in APAP-induced liver injury without or with LPS preconditioning, and it involves INF-ß-IRF1 signaling.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Acetaminofen/metabolismo , Acetaminofen/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Citocinas/metabolismo , Endotoxinas/metabolismo , Endotoxinas/toxicidade , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Lipopolissacarídeos/toxicidade , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ratos
7.
Chem Biodivers ; 20(9): e202300371, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37477112

RESUMO

The phytochemical analysis of ethyl acetate and methanol extract of Goniothalamus wynaadensis Bedd. leaves led to an isolation of eight (1-8) known molecules, among them seven (2-8) isolated for the first time from this species, which includes (+)-goniothalamin oxide (2), goniodiol-7-monoacetate (3), goniodiol-8-monoacetate (4), goniodiol (5), (+)-8-epi-9-deoxygoniopypyrone (6) etc. The phytochemical modification by acetylation of 3 and 4 gave goniodiol diacetate (9) with absolute configuration (6R, 7R, 8R) confirmed by single crystal X-ray diffraction. Compounds 3-9 were cytotoxic against breast, ovarian, prostate and colon cancer cell lines with IC50 <10 µM. Cell cycle analysis and Annexin-V assay on MDA-MB-231 cell using goniodiol-7-monoacetate (3) exhibited apoptotic response as well as necrotic response and showed cell proliferation arrest at G2/M phase. An in silico target identification for these molecules was carried out with an α-tubulin protein target by covalent docking. To gain an in-depth understanding and identify the stability of these protein-ligand complexes on thermodynamic energy levels, further assessment of the isolated molecules binding to the Cys-316 of α-tubulin was performed based on reaction energetic analysis via DFT studies which hinted the isolated molecules may be α-tubulin inhibitors similar to Pironetin. Molecular dynamics reiterated the observations.


Assuntos
Antineoplásicos , Goniothalamus , Estrutura Molecular , Tubulina (Proteína)/metabolismo , Estirenos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células , Simulação de Acoplamento Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Apoptose , Relação Estrutura-Atividade
8.
Chem Biodivers ; 20(9): e202300495, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37539766

RESUMO

The present study was designed to appraise the photoprotective, antioxidant, and antibacterial bioactivities of Ruellia tuberosa leaves extracts (RtPE, RtChl, RtEA, RtAc, RtMe, and RtHMe). The results showed that, RtHMe extracts of R. tuberosa was rich in total phenolic content, i. e., 1.60 mgGAE/g dry extract, while highest total flavonoid content was found in RtAc extract, i. e., 0.40 mgQE/g. RtMe showed effective antioxidant activity (%RSA: 58.16) at the concentration of 120 µL. RtMe, RtEA and RtHMe exhibited effective in vitro antibacterial activity against Gram-negative bacteria (E. coli). In silico docking studies revealed that paucifloside (-11.743 kcal/mol), indole-3-carboxaldehyde (-7.519 kcal/mol), nuomioside (-7.275 kcal/mol), isocassifolioside (-6.992 kcal/mol) showed best docking score against PDB ID 2EX8 [penicillin binding protein 4 (dacB) from Escherichia coli, complexed with penicillin-G], PDB ID 6CQA (E. coli dihydrofolate reductase protein complexed with inhibitor AMPQD), PDB ID 2Y2I [Penicillin-binding protein 1B in complex with an alkyl boronate (ZA3)] and PDB ID 2OLV (from S. aureus), respectively. Docked phytochemicals also showed good drug likeness properties.


Assuntos
Acanthaceae , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Compostos Fitoquímicos/farmacologia , Acanthaceae/química
9.
Int Tinnitus J ; 27(1): 40-46, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38050883

RESUMO

BACKGROUND: Tinnitus is the perception of sound in the absence of external acoustic stimulation. Being one of the most common diseases of the ear, it has a global prevalence ranging from 4.1 to 37.2%. To date, it has been difficult to treat tinnitus as its pathophysiology is poorly understood and there are limited treatment options. OBJECTIVE: To investigate the effect of OKN-007 (also known as HPN-07), a nitrone-based investigational drug, in combination with oral N-acetylcycsteine (NAC), for the treatment of hearing loss and chronic tinnitus under an individual expanded access protocol. PATIENT CASE: We report the case of a patient who presented with left-sided ear fullness, mild tinnitus, and mild high frequency sensorineural hearing loss with 100% word recognition. A large enhancing mass seen on MRI revealed a vestibular schwannoma. He underwent subtotal resection of the tumor resulting in a moderate-to-profound sensorineural hearing loss and catastrophic tinnitus. The patient was treated with intravenous OKN-007 at 60 mg/kg dosed three times per week and oral NAC 2500 mg twice daily. RESULTS: Post-treatment audiometric testing revealed an average of 16.66 dB in hearing threshold improvement in three frequencies (125, 250 and 500 Hz) with residual hearing in the affected left ear. His tinnitus loudness matching improved from 90 dB to 19 dB post-treatment. His Tinnitus Handicap Inventory improved from 86/100 (Catastrophic) to 40/100 (Moderate). He also experienced improvements in sleep, concentration, hearing, and emotional well-being, and reported significantly decreased levels of tinnitusrelated distress. CONCLUSIONS: This case report highlights the feasibility and therapeutic potential of the combination of OKN-007 and NAC in treating hearing loss and tinnitus that warrants further investigation.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Perda Auditiva Unilateral , Perda Auditiva , Neuroma Acústico , Zumbido , Masculino , Humanos , Zumbido/diagnóstico , Zumbido/tratamento farmacológico , Zumbido/etiologia , Perda Auditiva Unilateral/diagnóstico , Perda Auditiva Unilateral/etiologia , Perda Auditiva Unilateral/terapia , Neuroma Acústico/complicações , Neuroma Acústico/diagnóstico , Neuroma Acústico/cirurgia , Perda Auditiva/complicações
10.
J Cell Physiol ; 237(11): 4215-4225, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36098042

RESUMO

Liver depleted of hepatic stellate cells (HSCs) is resistant to ischemia/reperfusion-, concanavalin A-, and acetaminophen-induced acute injury. Whether HSCs regulate carbon tetrachloride (CCl4 )-induced acute liver injury is not known. CCl4 treatment damages pericentral hepatocytes that express CCl4 -metabolizing Cyp2E1 and activates HSCs. We investigated whether HSC-depletion in mice transgenic for thymidine kinase under the glial fibrillary acidic protein promoter (GFAP-TK-Tg) confers resistance to injury and inflammation due to CCl4 rechallenge. GFAP-TK-Tg or wild type (WT) mice were administered 0.16 ml/kg CCl4 (3× at 3 days intervals), then 40 µg/g/day ganciclovir for 10 days. The treatment depletes ~70%-75% HSCs from GFAP-TK-Tg but not WT mice while the liver recovers from earlier CCl4 -induced injury. Mice were then administered CCl4 , and liver injury and inflammation were determined at 24 h. HSC-depleted and HSC-sufficient mice showed similar CCl4 -induced hepatocyte necrosis and oxidative stress. However, increase in F4/80+ macrophages, but not CD68+ cells, was greater in CCl4 rechallenged HSC-depleted compared to HSC-sufficient mice. Expression of tumor necrosis factor-α (TNF-α), CCL2, and CXCL1 increased similarly, whereas increase in interleukin-6 (IL6), IL1ß, and IL10 expression was higher in CCl4 rechallenged HSC-depleted compared to HSC-sufficient mice. CCl4 rechallenge of HSC-sufficient mice rapidly activated HSCs causing significant fibrosis with increased expression of Col1a1, transforming growth factor ß1 (TGFß1), tissue inhibitors of metalloproteinases 1 (TIMP1); increase in TIPM1 was much lower and metalloproteinases 13 (MMP13) greater in CCl4 rechallenged HSC-depleted mice. Interestingly, hepatic recruitment of both profibrogenic (Ly6Chi ) and antifibrogenic restorative (Ly6Clo ) macrophages, and neutrophils was significantly greater in CCl4 rechallenged HSC-depleted mice. These data suggest that CCl4 directly damages hepatocytes but HSCs regulate inflammation. Rapid fibrogenesis in CCl4 rechallenged HSC-sufficient mice recovered from earlier injury indicates that even transiently activated HSCs that had reverted to the quiescent phenotype remain primed to become reactivated.


Assuntos
Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas , Camundongos , Animais , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Macrófagos/metabolismo , Inflamação/patologia , Cirrose Hepática/genética
11.
J Hepatol ; 77(5): 1410-1421, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35777586

RESUMO

Augmenter of liver regeneration (ALR), a ubiquitous fundamental life protein, is expressed more abundantly in the liver than other organs. Expression of ALR is highest in hepatocytes, which also constitutively secrete it. ALR gene transcription is regulated by NRF2, FOXA2, SP1, HNF4α, EGR-1 and AP1/AP4. ALR's FAD-linked sulfhydryl oxidase activity is essential for protein folding in the mitochondrial intermembrane space. ALR's functions also include cytochrome c reductase and protein Fe/S maturation activities. ALR depletion from hepatocytes leads to increased oxidative stress, impaired ATP synthesis and apoptosis/necrosis. Loss of ALR's functions due to homozygous mutation causes severe mitochondrial defects and congenital progressive multiorgan failure, suggesting that individuals with one functional ALR allele might be susceptible to disorders involving compromised mitochondrial function. Genetic ablation of ALR from hepatocytes induces structural and functional mitochondrial abnormalities, dysregulation of lipid homeostasis and development of steatohepatitis. High-fat diet-fed ALR-deficient mice develop non-alcoholic steatohepatitis (NASH) and fibrosis, while hepatic and serum levels of ALR are lower than normal in human NASH and NASH-cirrhosis. Thus, ALR deficiency may be a critical predisposing factor in the pathogenesis and progression of NASH.


Assuntos
Regeneração Hepática , Hepatopatia Gordurosa não Alcoólica , Trifosfato de Adenosina/metabolismo , Animais , Citocromos c/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Humanos , Lipídeos , Fígado/patologia , Regeneração Hepática/fisiologia , Camundongos , Mitocôndrias/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo
12.
Curr Oncol Rep ; 24(4): 501-515, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35192120

RESUMO

PURPOSE OF REVIEW: High-grade gliomas (HGG) are rare brain tumors that cause disproportionate suffering and mortality. Palliative care, whose aim is to relieve the symptoms and stressors of serious illness, may benefit patients with HGG and their families. In this review, we summarize the extant literature and provide recommendations for addressing the symptom management and communication needs of brain tumor patients and their caregivers at key points in the illness trajectory: initial diagnosis; during upfront treatment; disease recurrence; end-of-life period; and after death during bereavement. RECENT FINDINGS: Patients with HGG experience highly intrusive symptoms, cognitive and functional decline, and emotional and existential distress throughout the disease course. The caregiver burden is also substantial during the patient's illness and after death. There is limited evidence to guide the palliative management of these issues. Palliative care is likely to benefit patients with HGG, yet further research is needed to optimize the delivery of palliative care in neuro-oncology.


Assuntos
Neoplasias Encefálicas , Glioma , Assistência Terminal , Neoplasias Encefálicas/psicologia , Neoplasias Encefálicas/terapia , Glioma/patologia , Glioma/terapia , Humanos , Recidiva Local de Neoplasia , Cuidados Paliativos , Qualidade de Vida/psicologia
13.
Curr Neurol Neurosci Rep ; 22(7): 413-425, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35588045

RESUMO

PURPOSE OF REVIEW: Leptomeningeal disease (LMD) is a rare, late complication of systemic cancer and is associated with significant neurological morbidity and high mortality. Here we provide an overview of this condition, summarizing key recent research findings and clinical practice trends in its diagnosis and treatment. We also review current clinical trials for LMD. RECENT FINDINGS: Improved molecular diagnostic tools are in development to enable more sensitive detection of LMD, including circulating tumor cells and circulating tumor DNA. The use of targeted and CNS-penetrant therapeutics has shown survival improvements with tyrosine kinase inhibitors, antibody-drug conjugates, and select chemotherapy. However, these studies have primarily been phase I/II and retrospective analyses. There remains a dearth of clinical trials that include LMD patients. The combination of patient-specific molecular information and novel therapeutic approaches holds significant promise for improving outcomes in patients with LMD.


Assuntos
Neoplasias Meníngeas , Terapia Combinada , Progressão da Doença , Humanos , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/terapia , Estudos Retrospectivos
14.
Hepatology ; 72(5): 1800-1818, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32064648

RESUMO

BACKGROUND AND AIMS: During liver injury, quiescent hepatic stellate cells (qHSCs) transdifferentiate into proliferative and fibrogenic activated myofibroblastic phenotype (activated hepatic stellate cell; aHSCs) expressing smooth muscle α-actin (αSMA) and platelet-derived growth factor beta receptor (PDGFßR). Their interactions with gut-derived bacterial lipopolysaccharide (LPS) are implicated in hepatic fibrogenesis. However, LPS can also attenuate fibrogenic characteristics of aHSCs. APPROACH AND RESULTS: We examined molecular mechanisms of antifibrogenic effects of LPS on aHSCs in vitro and in vivo. Culture-activated rat HSCs were exposed to 0-100 ng/mL of LPS or its active component, diphosphoryl-lipid A (DPLA), and parameters of fibrosis and inflammatory cytokines/chemokines were determined by qRT-PCR, western, and immunohistochemical analyses. In vivo, HSCs were activated by repeated CCl4 administration to rats every 3 days for 3 or 8 weeks, then challenged with LPS (5 mg/kg; IP). HSCs were isolated 24 hours later, and fibrogenic/inflammatory parameters were analyzed. LPS induced phenotypic changes in aHSCs (rounding, size reduction) and loss of proliferation. LPS down-regulated expression of αSMA, PDGFßR, transforming growth factor beta receptor 1 (TGFßR1), collagen 1α1 (Col1α1), and fibronectin while up-regulating tumor necrosis factor alpha, interleukin-6, and C-X-C motif chemokine ligand 1 expression. LPS did not increase peroxisome proliferation-activated receptor gamma expression or lipid accumulation typical of qHSCs. DPLA elicited the same effects as LPS on aHSCs, indicating specificity, and monophosphoryl lipid A down-regulated fibrogenic markers, but elicited very weak inflammatory response. LPS down-regulated the expression of cMyb, a transcription factor for αSMA, and up-regulated small mother against decapentaplegic (SMAD)7 and CCAAT/enhancer-binding protein (C/EBP)δ, the transcriptional inhibitors of Col1α1 expression. In vivo LPS treatment of aHSCs inhibited their proliferation, down-regulated PDGFßR, αSMA, TGFßR1, Col1α1, and cMyb expression, and increased expression of SMAD7, C/EBPα, and C/EBPδ. CONCLUSIONS: In conclusion, LPS induces a unique phenotype in aHSCs associated with down-regulation of key fibrogenic mechanisms and thus may have an important role in limiting fibrosis.


Assuntos
Regulação da Expressão Gênica/imunologia , Células Estreladas do Fígado/imunologia , Lipídeo A/análogos & derivados , Cirrose Hepática Experimental/imunologia , Fígado/patologia , Animais , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Tetracloreto de Carbono/administração & dosagem , Tetracloreto de Carbono/toxicidade , Transdiferenciação Celular/imunologia , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Regulação para Baixo , Inativação Gênica , Células Estreladas do Fígado/patologia , Humanos , Lipídeo A/imunologia , Lipídeo A/metabolismo , Fígado/citologia , Fígado/imunologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/patologia , Camundongos , Camundongos Knockout , Miofibroblastos/imunologia , Miofibroblastos/patologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-myb/metabolismo , Ratos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Proteína Smad7/genética , Proteína Smad7/metabolismo , Regulação para Cima/imunologia
15.
Hepatology ; 72(5): 1586-1604, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32031683

RESUMO

BACKGROUND AND AIMS: The augmenter of liver regeneration (ALR) protein is critical for lipid homeostasis and mitochondrial function. We investigated high-fat/high-carbohydrate (HF/HC) diet-induced nonalcoholic fatty liver disease (NAFLD) in wild-type (WT), hepatocyte-specific ALR-knockout (ALR-H-KO), and ALR-heterozygous (ALR-H-HET) mice. ALR was measured in serum of human nonalcoholic steatohepatitis (NASH) and NASH-induced cirrhosis (serum and liver). APPROACH AND RESULTS: HF/HC feeding decreased ALR expression in all groups of mice. The otherwise normal ALR-H-HET mice gained more weight and steatosis than WT mice when challenged metabolically with the HF/HC diet; ALR-H-KO mice gained the least weight and had the least steatosis. These findings were consistent with correspondingly increased triglycerides and cholesterol and altered expression of carnitine palmitoyltransferase 1a, sterol regulatory element-binding protein, acetyl coenzyme A carboxylase, and fatty acid synthase. All HF/HC-fed mice developed insulin resistance, the magnitude being lower in ALR-H-KO mice. HF/HC-fed ALR-H-HET mice were more resistant to glucose challenge than WT or ALR-H-KO mice. The frequency of tumor necrosis factor alpha-producing, interleukin 6 (IL6)-producing, and IL17-producing cells was greater in ALR-H-KO than ALR-H-HET and lowest in WT mice. HF/HC feeding did not increase their number in ALR-H-KO mice, and the increase in ALR-H-HET was greater than that in WT mice except for IL17 cells. Cluster of differentiation 25-positive (CD25+ ) forkhead box P3-positive CD4+ regulatory T-cell frequency was lower in ALR-H-HET than WT mice and further reduced in ALR-H-KO mice; HF/HC reduced regulatory T-cell frequency only in WT mice. HF/HC-fed ALR-H-HET, but not WT, mice developed fibrosis; and ALR-H-KO mice progressed to cirrhosis. White adipose tissue of HF/HC-fed ALR-deficient mice developed strong inflammation, indicating bidirectional interactions with the liver. Hepatic and serum ALR levels were significantly reduced in patients with NASH-cirrhosis. Serum ALR was also significantly lower in patients with NASH. CONCLUSIONS: Hepatic ALR deficiency may be a critical predisposing factor for aggressive NAFLD progression.


Assuntos
Cirrose Hepática/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/deficiência , Adulto , Idoso , Animais , Biópsia , Colesterol/sangue , Colesterol/metabolismo , Dieta da Carga de Carboidratos/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Hepatectomia , Heterozigoto , Humanos , Resistência à Insulina , Fígado/cirurgia , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Regeneração Hepática , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/sangue , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Triglicerídeos/sangue , Triglicerídeos/metabolismo
16.
J Magn Reson Imaging ; 54(3): 739-749, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33738856

RESUMO

BACKGROUND: An imaging method that allows quantitative fibrosis estimates is needed to facilitate the diagnosis of chronic liver disease. Amide proton transfer (APT) and tissue sodium concentration (TSC) estimates could meet this need. HYPOTHESIS: APT and TSC estimates correlate with fibrosis in a mouse model of chronic liver disease. STUDY TYPE: Prospective. PHANTOMS/ANIMAL MODEL: Male C57Bl/6 mice given CCl4 or vehicle (N = 8 each) twice weekly for 16 weeks. FIELD STRENGTH/SEQUENCE: Liver T1 (Look-Locker gradient recalled echo [GRE] sequence), T2 (multiecho spin echo sequence), T1rho (fast spin echo sequence with 500 Hz spin locking pulse), and APT (GRE sequence with off-resonance pulses) data were acquired at 7 T at 12 and 16 weeks. Liver sodium data (multiple echo GRE sequence) were acquired at 12 weeks at 9.4 T. ASSESSMENT: Liver proton T1 , T2 , T1rho , APT, sodium T2 *, and TSC were calculated. Histological measures included Sirius Red, hematoxylin and eosin, liver hydroxyproline content, and serum alanine transaminase (ALT). STATISTICAL TESTS: Welch's two-sided t-test was used to test for differences between control and CCl4 -treated groups for serum ALT, hydroxyproline, Sirius Red staining, T1 , T2 , T1rho , APT, TSC, and sodium T2 *. Pearson's correlations between liver T1 , APT, TSC, or sodium T2 * with Sirius Red staining and hydroxyproline levels were calculated. RESULTS: APT was significantly different (P < 0.05) between groups in the left liver lobe at 16 weeks (CCl4 : 8.0% ± 1.2%, controls: 6.2% ± 1.0%), as were average liver TSC at 12 weeks (CCl4 : 38 mM ± 5 mM, controls: 27 mM ± 2 mM), and average sodium liver T2 * at 12 weeks (CCl4 : 10 msec ± 1.0 msec, controls: 12 msec ± 1.9 msec). APT, TSC, and sodium T2 * correlated significantly (P < 0.05) with Sirius Red staining and hydroxyproline levels. DATA CONCLUSION: Liver TSC and APT significantly correlated with histopathologic markers of fibrosis in this mouse model. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.


Assuntos
Cirrose Hepática , Imageamento por Ressonância Magnética , Animais , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Masculino , Camundongos , Imagens de Fantasmas , Estudos Prospectivos
17.
Theor Appl Genet ; 134(3): 849-858, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33388887

RESUMO

KEY MESSAGE: A new leaf rust resistance gene Lr80 was identified and closely linked markers were developed for its successful pyramiding with other marker-tagged genes to achieve durable control of leaf rust. Common wheat landrace Hango-2, collected in 2006 from the Himalayan area of Hango, District Kinnaur, in Himachal Pradesh, exhibited a very low infection type (IT;) at the seedling stage to all Indian Puccinia triticina (Pt) pathotypes, except the pathotype 5R9-7 which produced IT 3+. Genetic analysis based on Agra Local/Hango-2-derived F3 families indicated monogenic control of leaf rust resistance, and the underlying locus was temporarily named LrH2. Bulked segregant analysis using 303 simple sequence repeat (SSR) markers located LrH2 in the short arm of chromosome 2D. An additional set of 10 chromosome 2DS-specific markers showed polymorphism between the parents and these were mapped on the entire Agra Local/Hango-2 F3 population. LrH2 was flanked by markers cau96 (distally) and barc124 (proximally). The 90 K Infinium SNP array was used to identify SNP markers linked with LrH2. Markers KASP_17425 and KASP_17148 showed association with LrH2. Comparison of seedling leaf rust response data and marker locations across different maps demonstrated the uniqueness of LrH2 and it was formally named Lr80. The Lr80-linked markers KASP_17425, KASP_17148 and barc124 amplified alleles/products different to Hango-2 in 82 Australian cultivars indicating their robustness for marker-assisted selection of this gene in wheat breeding programs.


Assuntos
Basidiomycota/fisiologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Doenças das Plantas/genética , Proteínas de Plantas/genética , Triticum/genética , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Resistência à Doença/imunologia , Ligação Genética , Marcadores Genéticos , Doenças das Plantas/microbiologia , Triticum/imunologia , Triticum/microbiologia
18.
J Neurooncol ; 152(2): 313-323, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33486637

RESUMO

PURPOSE: Discordant prognostic awareness (PA) can cause distress, impact goals of care and future planning, especially in patients with high grade glioma (pwHGG) who have limited survival. We aimed to evaluate the feasibility of assessing PA of pwHGG, caregivers and clinicians using a single question and to evaluate these responses for discord, alignment and fluctuation over time. METHODS: This is a sub-study of an IRB-approved pilot study evaluating early palliative care and longitudinal symptom monitoring via a smart-device tool in 16 pwHGG and their caregivers receiving treatment at the Mayo Clinic Arizona (United States). Eligible patients were ≥ 18 years, English-speaking, newly-diagnosed, and had a willing caregiver. Participants answered a multiple-choice question asking for an estimate of their own or their loved one's survival on a monthly basis. RESULTS: All except one patient/caregiver dyad answered the question each time it was asked. The question did not appear to cause discomfort or increase conversations with clinicians around prognosis. PA of patients and caregivers fluctuated monthly, ranging from dismal to overtly optimistic, with a discordance frequency of 68%. Patients tended to be more optimistic than caregivers, and a higher QOL correlated to a more optimistic response. Clinicians' were more hopeful; their prediction tended to fluctuate less than those of patients and caregivers. CONCLUSIONS: PA may be assessed in pwHGG and caregivers with a single, frank question. There is clear discordance between PA of patients, their caregivers and clinicians. Understanding fluctuates longitudinally through disease and treatment course. Additional studies on timing and ways of discussing prognosis in this population are needed. CLINICAL TRIAL REGISTRATION: NCT04630379.


Assuntos
Neoplasias Encefálicas/mortalidade , Cuidadores , Compreensão , Glioma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Qualidade de Vida , Inquéritos e Questionários
19.
Physiol Plant ; 171(4): 882-895, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33179766

RESUMO

Selenium (Se) is a vital mineral for both plants and animals. It is widely distributed on the earth's crust and is taken up by the plants as selenite or selenate. Plants substantially vary in their physiological response to Se. The amount of Se in edible plants is genetically controlled. Its availability can be determined by measuring its phytoavailability in soil. The low concentration of Se in plants can help them in combating stress, whereas higher concentrations can be detrimental to plant health and in most cases it is toxic. Thus, solving the double-edged sword problem of nutritional Se deficiency and its elevated concentrations in environment requires a better understanding of Se uptake and metabolism in plants. The studies on Se uptake and metabolism can help in genetic biofortification of Se in plants and also assist in phytoremediation. Moreover, Se uptake and transport, especially biochemical pathways of assimilation and incorporation into proteins, offers striking mechanisms of toxicity and tolerance. These developments have led to a revival of Se research in higher plants with significant break throughs being made in the previous years. This review explores the new dimensions of Se research with major emphasis on key research events related to Se undertaken in last few years. Further, we also discussed future possibilities in Se research for crop improvement.


Assuntos
Selênio , Animais , Transporte Biológico , Plantas , Ácido Selênico , Solo
20.
Dermatol Ther ; 33(5): e13778, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32515033

RESUMO

The immune system of cancer patient gets compromised because of cancer therapy, surgery, and malignancy and thus the probability of infection are increased than the general patients. Immunosuppression can expose cancer patients to serious complications which can lead to delay in diagnosis and unnecessary hospitalizations that may adversely affect the prognosis of the disease. Patients who received chemotherapy or surgery within the 30 days before novel coronavirus disease pandemic have more risk of infection than the patients who had not undergone chemotherapy or surgery.


Assuntos
COVID-19/etiologia , Neoplasias/complicações , SARS-CoV-2 , Humanos , Neoplasias/imunologia , Neoplasias/terapia , Risco , Índice de Gravidade de Doença
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