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1.
Plant Physiol ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38805221

RESUMO

Heme, an organometallic tetrapyrrole, is widely engaged in oxygen transport, electron delivery, enzymatic reactions, and signal transduction. In plants, it is also involved in photomorphogenesis and photosynthesis. HEME OXYGENASE 1 (HO1) initiates the first committed step in heme catabolism, and it has generally been thought that this reaction takes place in chloroplasts. Here, we show that HO1 in both Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) has two transcription start sites (TSSs), producing long (HO1L) and short (HO1S) transcripts. Their products localize to the chloroplast and the cytosol, respectively. During early development or de-etiolation, the HO1L/HO1S ratio gradually increases. Light perception via phytochromes and cryptochromes elevates the HO1L/HO1S ratio in the whole seedling through the functions of ELONGATED HYPOCOTYL 5 (HY5) and HY5 HOMOLOG (HYH) and through the suppression of DE-ETIOLATED 1 (DET1), CONSTITUTIVE PHOTOMORPHOGENESIS 1 (COP1), and PHYTOCHROME INTERACTING FACTORs (PIFs). HO1L introduction complements the HO1-deficient mutant; surprisingly, HO1S expression also restores the short hypocotyl phenotype and high pigment content and helps the mutant recover from the genomes uncoupled (gun) phenotype. This indicates the assembly of functional phytochromes within these lines. Furthermore, our findings support the hypothesis that a mobile heme signal is involved in retrograde signaling from the chloroplast. Altogether, our work clarifies the molecular mechanism of HO1 TSS regulation and highlights the presence of a cytosolic bypass for heme catabolism in plant cells.

2.
Int J Cancer ; 154(9): 1587-1595, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38194606

RESUMO

Esophageal squamous cell carcinoma (ESCC) is the second most common cancer in Malawi. Risk factors for this cancer in Malawi are poorly understood. Poor oral health has previously been linked to increased ESCC risk in other high-incidence regions, including parts of Eastern and Southern Africa. We assessed the relationship between oral health and ESCC risk in a sex, age and location frequency-matched case-control study based at two hospitals in Lilongwe, Malawi from 2017 to 2020. Trained interviewers used a structured questionnaire and direct observation to collect data on demographics; behaviors; oral hygiene habits; the sum of decayed, missing or filled teeth (DMFT score); oral mucosa status; lip depigmentation and dental fluorosis via a visual scale. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CI), adjusted for known and suspected ESCC risk factors. During the study period, 300 cases and 300 controls were enrolled. Subjects in the highest tertile of DMFT score (≥7) had an increased risk of ESCC with an adjusted OR of 1.96 (95% CI: 1.16-3.36) compared to those with a DMFT score of 0. Severe dental fluorosis was associated with a statistically nonsignificant increased risk of ESCC (adjusted OR = 2.24, 95% CI: 0.97-5.49) compared to individuals with no fluorosis. Associations with oral mucosa status, lip depigmentation and toothbrushing method and frequency were mostly null or uncertain. Poor oral health, indicated by a higher DMFT score, was associated with increased ESCC risk in Malawi. Dental fluorosis is another possible risk factor in this population, but further evaluation is necessary to clarify any effects of fluorosis on ESCC risk.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Fluorose Dentária , Humanos , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Saúde Bucal , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/patologia , Fluorose Dentária/epidemiologia , Malaui/epidemiologia , Estudos de Casos e Controles , Fatores de Risco
3.
Hum Mol Genet ; 31(20): 3558-3565, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-35717579

RESUMO

Although multiple common susceptibility loci for lung cancer (LC) have been identified by genome-wide association studies, they can explain only a small portion of heritability. The etiological contribution of rare deleterious variants (RDVs) to LC risk is not fully characterized and may account for part of the missing heritability. Here, we sequenced the whole exomes of 2777 participants from the Environment and Genetics in Lung cancer Etiology study, a homogenous population including 1461 LC cases and 1316 controls. In single-variant analyses, we identified a new RDV, rs77187983 [EHBP1, odds ratio (OR) = 3.13, 95% confidence interval (CI) = 1.34-7.30, P = 0.008] and replicated two previously reported RDVs, rs11571833 (BRCA2, OR = 2.18; 95% CI = 1.25-3.81, P = 0.006) and rs752672077 (MPZL2, OR = 3.70, 95% CI = 1.04-13.15, P = 0.044). In gene-based analyses, we confirmed BRCA2 (P = 0.007) and ATM (P = 0.014) associations with LC risk and identified TRIB3 (P = 0.009), involved in maintaining genome stability and DNA repair, as a new candidate susceptibility gene. Furthermore, cases were enriched with RDVs in homologous recombination repair [carrier frequency (CF) = 22.9% versus 19.5%, P = 0.017] and Fanconi anemia (CF = 12.5% versus 10.2%, P = 0.036) pathways. Our results were not significant after multiple testing corrections but were enriched in cases versus controls from large scale public biobank resources, including The Cancer Genome Atlas, FinnGen and UK Biobank. Our study identifies novel candidate genes and highlights the importance of RDVs in DNA repair-related genes for LC susceptibility. These findings improve our understanding of LC heritability and may contribute to the development of risk stratification and prevention strategies.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias Pulmonares , Reparo do DNA/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Células Germinativas , Humanos , Neoplasias Pulmonares/genética
4.
Mol Biol Rep ; 51(1): 351, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38400865

RESUMO

The nervous system possesses the remarkable ability to undergo changes in order to store information; however, it is also susceptible to damage caused by invading pathogens or neurodegenerative processes. As a member of nucleotide-binding oligomerization domain-like receptor (NLR) family, the NLRP6 inflammasome serves as a cytoplasmic innate immune sensor responsible for detecting microbe-associated molecular patterns. Upon activation, NLRP6 can recruit the adapter protein apoptosis-associated speck-like protein (ASC) and the inflammatory factors caspase-1 or caspase-11. Consequently, inflammasomes are formed, facilitating the maturation and secretion of pro-inflammatory cytokines such as inflammatory factors-18 (IL-18) and inflammatory factors-1ß (IL-1ß). Precise regulation of NLRP6 is crucial for maintaining tissue homeostasis, as dysregulated inflammasome activation can contribute to the development of various diseases. Furthermore, NLRP6 may also play a role in the regulation of extraintestinal diseases. In cells of the brain, such as astrocytes and neurons, NLRP6 inflammasome are also present. Here, the assembly and subsequent activation of caspase-1 mediated by NLRP6 contribute to disease progression. This review aims to discuss the structure and function of NLRP6, explain clearly the mechanisms that induce and activate NLRP6, and explore its role within the central and peripheral nervous system.


Assuntos
Inflamassomos , Doenças do Sistema Nervoso , Humanos , Inflamassomos/metabolismo , Citocinas/metabolismo , Caspase 1/metabolismo , Apoptose , Doenças do Sistema Nervoso/genética , Caspases , Peptídeos e Proteínas de Sinalização Intracelular
5.
Food Microbiol ; 119: 104447, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225049

RESUMO

Yarrowia lipolytica N12 and A13 with high lipase activity obtained by mutagenesis were inoculated into sour meat, and their effects on physicochemical properties, microbial community succession, free amino acids, and volatile compounds of sour meat were investigated. Inoculation fermentation increased the contents of free amino acids observably, rapidly reduced pH, promoted the accumulation of total acids, decreased 2-thiobarbituric acid reactive substances (TBARS) values. In addition, the addition of Y. lipolytica might contribute to the growth of lactic acid bacteria, Candida spp., and Debaryomyces udenii, which play an important role in production of volatile compounds. It was shown that inoculation promoted the production of esters, aldehydes, and alcohols, especially ethyl esters, giving sour meat a better meat flavor. Besides, it was found that Y. lipolytica A13 had better fermenting property. Sample of A13 group had higher contents of ethyl esters, free amino acids and dominant microorganisms. The results may help to provide new strains for sour meat fermentation.


Assuntos
Lactobacillales , Saccharomycetales , Yarrowia , Yarrowia/genética , Ésteres/metabolismo , Lactobacillales/genética , Lactobacillales/metabolismo , Fermentação , Aminoácidos/metabolismo , Carne
6.
Mol Pharm ; 20(1): 473-480, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36305620

RESUMO

Noninvasive single-photon emission computed tomography (SPECT) imaging with [99mTc]Tc-HYNFA via folate receptor (FR) targeting was proposed to assess the inflammation and therapeutic effect of systemic sclerosis (SSc) in model mice. The radiochemical yield and purity of [99mTc]Tc-HYNFA were over 95%, with a specific activity of about 9.36 ± 0.17 MBq/nmol. At the end of induction, the uptake ratios of bleomycin-injected regions on the back-to-muscle (R/M) and lung-to-muscle (L/M) derived from SPECT images were 7.27 ± 0.50 and 4.25 ± 0.15, respectively. The radioactivity uptakes could be blocked by excessive folic acid (FA), and R/M and L/M obviously decreased to 2.78 ± 0.57 and 2.51 ± 0.79, respectively. R/M (2.22 ± 0.71) and L/M (1.62 ± 0.28) decreased very close to those of the control mice group (R/M = 1.99 ± 0.36, L/M = 1.50 ± 0.14) when macrophages had been depleted in advance. After being treated with cyclophosphamide (CTX) or methotrexate (MTX), R/M and L/M decreased to 3.58 ± 0.52 and 2.03 ± 0.32 (CTX treatment) or 2.48 ± 0.64 and 1.83 ± 0.06 (MTX treatment). R/M and L/M were highly correlated with pathological changes. The trend of hydroxyproline content in lungs at the later non-inflammatory phase of each group was similar to the uptake values of the lung in the 4th week from the beginning of induction. [99mTc]Tc-HYNFA had an ideal uptake in SSc lesions. R/M and L/M had a high consistency with pathological changes. SPECT imaging-targeted FR could monitor the therapeutic effect of CTX and MTX. It is expected to be an effective means to evaluate SSc.


Assuntos
Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Animais , Camundongos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Compostos Radiofarmacêuticos/química , Ácido Fólico/química , Metotrexato
7.
Mol Pharm ; 20(7): 3529-3538, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37243620

RESUMO

The stimulator of interferon genes (STING) is a pivotal protein in the production of STING-dependent type I interferon, which has the potential to enhance tumor rejection. The visualization of STING in the tumor microenvironment is valuable for STING-related treatments, but few STING imaging probes have been reported to date. In this study, we developed a novel 18F-labeled agent ([18F]F-CRI1) with an acridone core structure for the positron emission tomography (PET) imaging of STING in CT26 tumors. The probe was successfully prepared with a nanomolar STING binding affinity of Kd = 40.62 nM. [18F]F-CRI1 accumulated quickly in the tumor sites and its uptake reached a maximum of 3.02 ± 0.42% ID/g after 1 h i.v. injection. The specificity of [18F]F-CRI1 was confirmed both in in vitro cell uptake and in vivo PET imaging by blocking studies. Our findings suggest that [18F]F-CRI1 may be a potential agent for visualizing STING in the tumor microenvironment.


Assuntos
Radioisótopos de Flúor , Neoplasias , Humanos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias/diagnóstico por imagem , Interferons , Linhagem Celular Tumoral , Microambiente Tumoral
8.
Metab Brain Dis ; 38(4): 1143-1153, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36745250

RESUMO

Glioma is the most common malignant tumor of the central nervous system. The urea cycle (UC) is an essential pathway to convert excess nitrogen and ammonia into the less toxic urea in humans. However, less is known about the functional significance of the urea cycle in glioma. p53 functions as a tumor suppressor and modulates several cellular functions and disease processes. In the present study, we aimed to explore whether p53 influences glioma progression by regulating the urea cycle. Here, we demonstrated the inhibitory impact of p53 on the expression of urea cycle enzymes and urea genesis in glioma cells. The level of polyamine, a urea cycle metabolite, was also regulated by p53 in glioma cells. Carbamoyl phosphate synthetase-1 (CPS1) is the first key enzyme involved in the urea cycle. Functionally, we demonstrated that CPS1 knockdown suppressed glioma cell proliferation, migration and invasion. Mechanistically, we demonstrated that the expression of ornithine decarboxylase (ODC), which determines the generation of polyamine, was regulated by CPS1. In addition, the impacts of p53 knockdown on ODC expression, glioma cell growth and aggressive phenotypes were significantly reversed by CPS1 inhibition. In conclusion, these results demonstrated that p53 inhibits polyamine metabolism by suppressing the urea cycle, which inhibits glioma progression.


Assuntos
Glioma , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular , Carbamoil-Fosfato Sintase (Amônia)/genética , Carbamoil-Fosfato Sintase (Amônia)/metabolismo , Poliaminas/metabolismo , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Ureia/farmacologia , Ureia/metabolismo
9.
J Sci Food Agric ; 103(5): 2304-2312, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36636889

RESUMO

BACKGROUND: Studies have shown that either the addition of starter culture or enzyme can improve fermentation in fish or other products. However, little research has been carried out on the effects of coupling starter cultures with lipase on the microbial community and product quality. Suanzhayu is a Chinese fermented fish product that mainly relies on spontaneous fermentation, resulting in an unstable flavor and quality. The present study investigated the impact of lipase and Lactiplantibacillus plantarum 1-24-LJ on the quality of Suanzhayu. RESULTS: Inoculation decreased pH and 2-thiobarbituric acid reactive substances (TBARS) values, and also helped the dominance of the strain in the ecosystem, whereas lipase addition raised TBARS values and had little effect on pH, water activity (aw ) and microbiota. The addition of lipase and/or Lpb. plantarum increased the content of alcohols, aldehydes, ketones, esters and umami amino acids. The co-additions with the most significant effect and the total contents of volatile compounds (VCs) and free amino acids (FAAs) were 1801.92 g per 100 g and 21 357.05 mg per 100 g, respectively. Former-Lactobacillus was negatively correlated with pH, aw and Prevotella, but positively with VCs (ethyl ester of heptanoic acid, ethyl ester of octanoic acid) and FAAs (Tyr, Phe). Furthermore, adding Lpb. plantarum 1-24-LJ alone or in combination with lipase shortened the fermentation process. CONCLUSION: The present study provides a recommended Suanzhayu process approach for improving product quality and flavor, as well as shortening fermentation time, by adding Lpb. plantarum 1-24-LJ with or without lipase. © 2023 Society of Chemical Industry.


Assuntos
Lactobacillus plantarum , Animais , Lactobacillus plantarum/metabolismo , Lipase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Ecossistema , Microbiologia de Alimentos , Fermentação , Aminoácidos/metabolismo
10.
J Integr Plant Biol ; 65(3): 791-809, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36226597

RESUMO

It is of great importance to better understand how trees regulate nitrogen (N) uptake under N deficiency conditions which severely challenge afforestation practices, yet the underlying molecular mechanisms have not been well elucidated. Here, we functionally characterized PuHox52, a Populus ussuriensis HD-ZIP transcription factor, whose overexpression greatly enhanced nutrient uptake and plant growth under N deficiency. We first conducted an RNA sequencing experiment to obtain root transcriptome using PuHox52-overexpression lines of P. ussuriensis under low N treatment. We then performed multiple genetic and phenotypic analyses to identify key target genes of PuHox52 and validated how they acted against N deficiency under PuHox52 regulation. PuHox52 was specifically induced in roots by N deficiency, and overexpression of PuHox52 promoted N uptake, plant growth, and root development. We demonstrated that several nitrate-responsive genes (PuNRT1.1, PuNRT2.4, PuCLC-b, PuNIA2, PuNIR1, and PuNLP1), phosphate-responsive genes (PuPHL1A and PuPHL1B), and an iron transporter gene (PuIRT1) were substantiated to be direct targets of PuHox52. Among them, PuNRT1.1, PuPHL1A/B, and PuIRT1 were upregulated to relatively higher levels during PuHox52-mediated responses against N deficiency in PuHox52-overexpression lines compared to WT. Our study revealed a novel regulatory mechanism underlying root adaption to N deficiency where PuHox52 modulated a coordinated uptake of nitrate, phosphate, and iron through 'PuHox52-PuNRT1.1', 'PuHox52-PuPHL1A/PuPHL1B', and 'PuHox52-PuIRT1' regulatory relationships in poplar roots.


Assuntos
Ferro , Populus , Nitratos , Populus/genética , Nitrogênio/metabolismo , Fosfatos , Raízes de Plantas/genética , Regulação da Expressão Gênica de Plantas
11.
Pharmacol Res ; 183: 106395, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35970328

RESUMO

Riboflavin receptor 3 (RFVT3) is a key protein in energetic metabolism reprogramming and is overexpressed in multiple cancers involved in malignant proliferation, angiogenesis, chemotherapy resistance, and immunosuppression. To enable non-invasive real-time quantification of RFVT3 in tumors, we sought to develop a suitable PET probe that would allow specific and selective RFVT3 imaging in vivo. A novel radiofluorinated riboflavin probe (18F-RFTA) based on riboflavin was synthesized and characterized in terms of radiochemical purity, hydrophilicity, binding affinity, and stability. Positron emission tomography (PET) imaging of 18F-RFTA was performed in U87MG tumor-bearing mice. Immunohistochemistry staining was carried out to determine the expression of RFVT3 in U87MG tumors. 18F-RFTA was characterized by high radiochemical purity and RFVT3 binding affinity, and remarkable stability in vitro and in vivo. Small-animal PET imaging with 18F-RFTA revealed significantly higher uptake in RFVT3-expressing U87MG tumors than in muscle. In conclusion, we have developed the first radiofluorinated riboflavin-based PET probe that is suitable for imaging RFVT3-positive tumors. The new target/probe system can be leveraged for extensive use in the diagnosis and treatment of RFVT3 overexpressing diseases, such as oncologic, cardiovascular, and neurodegenerative diseases.


Assuntos
Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Animais , Linhagem Celular Tumoral , Camundongos , Neovascularização Patológica , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Riboflavina/metabolismo
12.
BMC Cancer ; 21(1): 589, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022824

RESUMO

BACKGROUND: Blood type has been associated with the risk of gastric cancer, but few studies have examined the association with esophageal squamous cell carcinoma (ESCC). METHODS: We conducted a case-control study using genotyping data of Chinese individuals, including cases of 2022 ESCC, 1189 gastric cardia adenocarcinoma, 1161 gastric noncardia adenocarcinoma, and 2696 controls. Genetic blood type was imputed using three single nucleotide polymorphisms. We used logistic regression to examine the association between blood type and the risk of each cancer. RESULTS: Compared to blood type O, the risk of ESCC was significantly elevated for blood type B and AB, with the highest risk for type AB (OR, 95%CI: 1.34, 1.07-1.67). Analysis of genotype suggested that the association of ESCC was from carrying the B allele. Similarly, blood type was significantly associated with gastric noncardia adenocarcinoma (P < 0.001) with risk significantly elevated in type A (1.37, 1.14-1.65) and AB (1.44, 1.10-1.89) compared to type O. Blood type was not associated with gastric cardia adenocarcinoma (P = 0.13). CONCLUSIONS: This study provides novel insights into the association between blood type and the risk of ESCC and restricted previously observed association to only gastric noncardia cancer, providing important evidence to clarify the pattern of association and suggesting mechanisms of action.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Adenocarcinoma/epidemiologia , Neoplasias Esofágicas/epidemiologia , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Neoplasias Gástricas/epidemiologia , Adenocarcinoma/sangue , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Neoplasias Esofágicas/sangue , Carcinoma de Células Escamosas do Esôfago/sangue , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Medição de Risco/métodos , Neoplasias Gástricas/sangue
13.
J Infect Dis ; 221(11): 1855-1863, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-31900482

RESUMO

BACKGROUND: Noroviruses are a leading cause of acute gastroenteritis. Genogroup 2 type 4 (GII.4) has been the dominant norovirus genotype worldwide since its emergence in the mid-1990s. Individuals with a functional fucosyltransferase-2 gene, known as secretors, have increased susceptibility to GII.4 noroviruses. We hypothesized that this individual-level trait may drive GII.4 norovirus predominance at the human population level. METHODS: We conducted a systematic review for studies reporting norovirus outbreak or sporadic case genotypes and merged this with data on proportions of human secretor status in various countries from a separate systematic review. We used inverse variance-weighted linear regression to estimate magnitude of the population secretor-GII.4 proportion association. RESULTS: Two hundred nineteen genotype and 112 secretor studies with data from 38 countries were included in the analysis. Study-level GII.4 proportion among all noroviruses ranged from 0% to 100%. Country secretor proportion ranged from 43.8% to 93.9%. We observed a 0.69% (95% confidence interval, 0.19-1.18) increase in GII.4 proportion for each percentage increase in human secretor proportion, controlling for Human Development Index. CONCLUSIONS: Norovirus evolution and diversity may be driven by local population human host genetics. Our results may have vaccine development implications including whether specific antigenic formulations would be required for different populations.


Assuntos
Infecções por Caliciviridae/transmissão , Infecções por Caliciviridae/genética , Infecções por Caliciviridae/virologia , Surtos de Doenças/prevenção & controle , Feminino , Fucosiltransferases , Genótipo , Saúde Global , Humanos , Masculino , Norovirus/classificação , Norovirus/genética , Filogenia , Galactosídeo 2-alfa-L-Fucosiltransferase
14.
Metab Eng ; 61: 120-130, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32474056

RESUMO

Adaptive laboratory evolution is often used to improve the performance of microbial cell factories. Reverse engineering of evolved strains enables learning and subsequent incorporation of novel design strategies via the design-build-test-learn cycle. Here, we reverse engineer a strain of Escherichia coli previously evolved for increased tolerance of octanoic acid (C8), an attractive biorenewable chemical, resulting in increased C8 production, increased butanol tolerance, and altered membrane properties. Here, evolution was determined to have occurred first through the restoration of WaaG activity, involved in the production of lipopolysaccharides, then an amino acid change in RpoC, a subunit of RNA polymerase, and finally mutation of the BasS-BasR two component system. All three mutations were required in order to reproduce the increased growth rate in the presence of 20 mM C8 and increased cell surface hydrophobicity; the WaaG and RpoC mutations both contributed to increased C8 titers, with the RpoC mutation appearing to be the major driver of this effect. Each of these mutations contributed to changes in the cell membrane. Increased membrane integrity and rigidity and decreased abundance of extracellular polymeric substances can be attributed to the restoration of WaaG. The increase in average lipid tail length can be attributed to the RpoCH419P mutation, which also confers tolerance to other industrially-relevant inhibitors, such as furfural, vanillin and n-butanol. The RpoCH419P mutation may impact binding or function of the stringent response alarmone ppGpp to RpoC site 1. Each of these mutations provides novel strategies for engineering microbial robustness, particularly at the level of the microbial cell membrane.


Assuntos
Caprilatos/metabolismo , RNA Polimerases Dirigidas por DNA , Proteínas de Escherichia coli , Escherichia coli , Glucosiltransferases , Engenharia Metabólica , Mutação de Sentido Incorreto , Substituição de Aminoácidos , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo
15.
New Phytol ; 228(4): 1369-1385, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32589766

RESUMO

Adventitious root (AR) formation is critically important in vegetative propagation through cuttings in some plants, especially woody species. However, the underlying molecular mechanisms remain elusive. Here, we report the identification of a poplar homeobox gene, PuHox52, which was induced rapidly (within 15 min) at the basal ends of stems upon cutting and played a key regulatory role in adventitious rooting. We demonstrated that overexpression of PuHox52 significantly increased the number of ARs while suppression of PuHox52 had the opposite effect. A multilayered hierarchical gene regulatory network (ML-hGRN) mediated by PuHox52 was reverse-engineered and demonstrated to govern AR formation. PuHox52 regulated AR formation through upregulation of nine hub regulators, including a jasmonate signaling pathway gene, PuMYC2, and an auxin signaling pathway gene, PuAGL12. We also identified coherent type 4 feed-forward loops within this ML-hGRN; PuHox52 repressed PuHDA9, which encodes a histone deacetylase, and led to an increase in acetylation and presumably expression of three hub regulators, PuWRKY51, PuLBD21 and PuIAA7. Our results indicate that the ML-hGRN mediated by PuHox52 governs AR formation at the basal ends of stem cuttings from poplar trees.


Assuntos
Populus , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Ácidos Indolacéticos , Raízes de Plantas/genética , Populus/genética , Transdução de Sinais
16.
Plant Physiol ; 180(4): 2254-2271, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31221731

RESUMO

Zinc (Zn) is an essential micronutrient but in excess is highly toxic to plants. Plants regulate Zn homeostasis and withstand excess Zn through various pathways; these pathways are generally tightly regulated by a specific set of genes. However, the transcription factors involved in excess Zn tolerance have yet to be identified. Here, we characterized a Populus ussuriensis heat shock transcription factor A4a (PuHSFA4a) that acts as a positive regulator of excess Zn tolerance in P ussuriensis We used overexpression (PuHSFA4a-OE) and chimeric dominant repressor (PuHSFA4a-SRDX) lines to identify the targets of PuHSFA4a PuHSFA4a transcription is specifically induced in roots by high Zn. Overexpression of PuHSFA4a conferred excess Zn tolerance and a dominant repressor version of PuHSFA4a increased excess Zn sensitivity in P ussuriensis by regulating the antioxidant system in roots. PuHSFA4a coordinately activates genes related to abiotic stress responses and root development and directly binds to the promoter regions of glutathione-s-transferase U17 (PuGSTU17) and phospholipase A2 (PuPLA2 ). PuGSTU17 overexpression significantly increased GST activity and reduced reactive oxygen species levels in roots while PuGSTU17-RNA interference lines exhibited the opposite phenotype. Furthermore, PuPLA2 overexpression promoted root growth under high Zn stress. Taken together, we provide evidence that PuHSFA4a coordinately activates the antioxidant system and root development-related genes and directly targets PuGSTU17 and PuPLA, thereby promoting excess Zn tolerance in P ussuriensis roots.


Assuntos
Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Populus/efeitos dos fármacos , Populus/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Zinco/farmacologia , Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Ecotoxicol Environ Saf ; 206: 111164, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32858327

RESUMO

Pig farm wastewater treatment plants (WWTPs) are an important repository for resistant bacterial communities (RBCs) and antibiotic resistance genes (ARGs). However, the relationship between RBCs and ARG hosts has not been well characterized. In this study, water samples from influent and effluent from five pig farm WWTPs were collected. Gradient concentrations of doxycycline (DOX) were used to screen the culturable RBCs. The abundance of 21 subtypes of ARGs and the bacterial community were investigated. This study detected a large number of culturable DOX-RBCs and ARGs in the influent and effluent of pig farm WWTPs. The abundances of ARGs and RBCs in all effluent samples was significantly lower than that in the influent samples (P < 0.05), which indicated that the WWTPs can effectively remove most ARGs and RBCs in pig farm wastewater. The main potential culturable RBCs in pig farm wastewater were the dominant bacteria Proteobacteria, Actinobacteria, Pseudomonas, and Rheinheimera. However, most of the ARGs were mainly present in Bacteroidetes, Actinobacteria, Corynebacteriaceae, Macellibacteroides, Acinetobacter, and Enterobacteriaceae, which are considered potential ARG hosts. The results presented here showed that there were obvious differences between the species of culturable DOX-RBCs and ARG hosts in the pig farm WWTPs, which may be due to various environmental factors. This highlights the urgent need for further research on the relationship between RBCs and ARG hosts.


Assuntos
Doxiciclina , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Eliminação de Resíduos Líquidos , Águas Residuárias/microbiologia , Animais , Bactérias/efeitos dos fármacos , Fazendas , Suínos
18.
Clin Infect Dis ; 68(1): 96-105, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29788074

RESUMO

Background: Periodic mass distribution of benzimidazole anthelminthic drugs is the key strategy to control soil-transmitted helminths (STHs) globally. However, benzimidazoles have low efficacy against Trichuris trichiura, and there are concerns about benzimidazole resistance potentially emerging in humans. Therefore, identifying alternative drug regimens is a pressing priority. We present a systematic review and network meta-analysis comparing the efficacy of 21 different anthelminthic drug regimens, including standard, novel, and combination treatments. Methods: We searched PubMed, Medline, Embase, Web of Science, and Cochrane databases and identified studies comparing anthelminthic treatments to each other or placebo. The outcomes calculated were relative risk (RR) of cure and difference in egg reduction rates (dERR). We used an automated generalized pairwise modeling framework to generate mixed treatment effects against a common comparator, the current standard treatment (single-dose albendazole). Results: Our search identified 4876 studies, of which 114 were included in the meta-analysis. Results identified several drug combinations with higher efficacy than single-dose albendazole for T. trichiura, including albendazole-ivermectin (RR of cure, 3.22 [95% confidence interval {CI}, 1.84-5.63]; dERR, 0.97 [95% CI, .21-1.74]), albendazole-oxantel pamoate (RR, 5.07 [95% CI, 1.65-15.59]; dERR, 0.51 [95% CI, .50-.52]), mebendazole-ivermectin (RR, 3.37 [95% CI, 2.20-5.16]), and tribendimidine-oxantel pamoate (RR, 4.06 [95% CI, 1.30-12.64]). Conclusions: There are several promising drug combinations that may enhance the impact of STH control programs on T. trichiura, without compromising efficacy against Ascaris lumbricoides and hookworm. We suggest further, large-scale trials of these drug combinations and consideration of their use in STH control programs where T. trichiura is present. International Prospective Register of Systematic Reviews Registration: CRD42016050739.


Assuntos
Anti-Helmínticos/administração & dosagem , Ascaríase/tratamento farmacológico , Tricuríase/tratamento farmacológico , Combinação de Medicamentos , Humanos , Administração Massiva de Medicamentos/métodos , Placebos/administração & dosagem , Estudos Prospectivos , Resultado do Tratamento
19.
Clin Infect Dis ; 69(9): 1545-1552, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30602004

RESUMO

BACKGROUND: The early detection of enteric infections in older adults is challenging because typical signs and symptoms of disease may be less common, absent, or overlooked. Understanding illness characteristics of enteric infections among older adults could improve the timeliness and accuracy of clinical diagnoses, thereby improving patient outcomes and increasing cases reported to surveillance. METHODS: Here, we describe illness characteristics (percentage reporting bloody diarrhea, fever, vomiting, abdominal pain; percentage hospitalized; duration of hospitalization; and duration of illness) among older adults (≥65 years) with acute gastroenteritis and culture-confirmed Campylobacter and nontyphoidal Salmonella infections in Australia, Canada, and the United States and compare these characteristics with those among younger people (<5 years, 5-24 years, and 25-64 years). RESULTS: A significant negative correlation was found between all symptoms and increasing age group, except for bloody diarrhea in cases of acute gastroenteritis. Adults aged ≥85 years reported bloody diarrhea in only 9% of nontyphoidal Salmonella and 4% of Campylobacter infections compared with 59% and 55% among children aged <5 years. Conversely, a greater percentage of older adults (≥65) than younger persons (<5, 5-24, 25-64) reported being hospitalized, with an increasing linear relationship in age groups 65 years and older. CONCLUSIONS: Although older adults are more likely to have severe illness and be hospitalized, we found that the proportion of persons reporting symptoms typically associated with enteric infections decreases with age. These findings have implications for clinical recognition and treatment of gastrointestinal illness, as well as for public health research.


Assuntos
Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter/patogenicidade , Gastroenterite/tratamento farmacológico , Gastroenterite/microbiologia , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/microbiologia , Adolescente , Adulto , Antibacterianos/uso terapêutico , Austrália , Canadá , Criança , Pré-Escolar , Hospitalização/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
20.
Soc Psychiatry Psychiatr Epidemiol ; 54(10): 1189-1198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30989255

RESUMO

PURPOSE: We know little about how community structures influence the risk of common mental illnesses. This study presents a new way to establish links between depression and social fragmentation, thereby identifying pathways to better target mental health services and prevention programs to the right people in the right place. METHOD: A principal components analysis (PCA) was conducted to develop the proposed Australian neighborhood social fragmentation index (ANSFI). General practice clinical data were used to identify cases of diagnosed depression. The association between ANSFI and depression was explored using multilevel logistic regression. Spatial hot spots (clusters) of depression prevalence and social fragmentation at the statistical area level 1 (SA1) were examined. RESULTS: Two components of social fragmentation emerged, reflecting fragmentation related to family structure and mobility. Individuals treated for depression in primary care were more likely to live in neighborhoods with lower socioeconomic status and with higher social fragmentation related to family structure. A 1-SD increase in social fragmentation was associated with a 16% higher depression prevalence (95% CI 11%, 20%). However, the association attenuated with adjustment for neighborhood socio-economic status. Considerable spatial variation in social fragmentation and depression patterns across communities was observed. CONCLUSIONS: Developing a social fragmentation index for the first time in Australia at a small area level generates a new line of knowledge on the impact of community structures on health risks. Findings may extend our understanding of the mechanisms that drive geographical variation in the incidence of common mental disorders and mental health care.


Assuntos
Depressão/epidemiologia , Características de Residência/estatística & dados numéricos , Classe Social , Análise Espacial , Adulto , Austrália/epidemiologia , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Serviços de Saúde Mental , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
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