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1.
Blood Sci ; 6(1): e00178, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38213825

RESUMO

Letermovir is a specific inhibitor of cytomegalovirus (CMV) terminase complex. Several studies have reported that letermovir can effectively prevent CMV activation after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We aimed to identify the efficacy and safety of letermovir prophylaxis for CMV infection after allo-HSCT with a systemic review and meta-analysis. A literature search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. PubMed and Embase databases were searched. A total of 28 studies were included. The incidence of CMV activation at 14 weeks after HSCT was 0.10 (95% confidence interval [CI], 0.06-0.18), which was 0.10 (95% CI, 0.04-0.21) and 0% in adult and children (2 studies were included and both of them were 0%). In addition, the incidence of CMV activation at 14 weeks after allo-HSCT was 0.11 (95% CI, 0.06-0.21) and 0.07 (only 1 study included), respectively, in retrospective and prospective studies. The incidence of CMV activation at 100 and 200 days after HSCT was 0.23 (95% CI, 0.16-0.33) and 0.49 (95% CI, 0.32-0.67), respectively. The incidence of CMV disease at 14 weeks and at 6 months after HSCT was 0.01 (95% CI, 0.01-0.02) and 0.03 (95% CI, 0.01-0.09), respectively. Thus, our systemic review and meta-analysis suggested that letermovir prophylaxis was safe and effective for CMV activation after allo-HSCT.

2.
Phytochemistry ; 213: 113775, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37392937

RESUMO

This work reports the isolation of seven undescribed polyphenolic glycosides (1-7) together with fourteen known compounds (8-21) from the fruit of Lycium ruthenicum Murray. The structures of the undescribed compounds were identified based on comprehensive spectroscopic methods including IR, HRESIMS, NMR and ECD, and chemical hydrolysis. Compounds 1-3 possess an unusual four-membered ring, while 11-15 were firstly isolated from this fruit. Interestingly, compounds 1-3 inhibited monoamine oxidase B with IC50 of 25.36 ± 0.44, 35.36 ± 0.54, and 25.12 ± 1.59 µM, respectively, and showed significant neuroprotective effect on PC12 cells injured by 6-OHDA. Moreover, compound 1 improved the lifespan, dopamine level, climbing behavior, and olfactory ability of the PINK1B9 flies, a Drosophila model of Parkinson's disease. This work presents the first in vivo neuroprotective evidence of the small molecular compounds in L. ruthenicum Murray fruit, indicating its good potential as neuroprotectant.


Assuntos
Lycium , Fármacos Neuroprotetores , Glicosídeos/química , Lycium/química , Fármacos Neuroprotetores/farmacologia , Frutas/química
3.
Plant Foods Hum Nutr ; 78(1): 68-75, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36322321

RESUMO

Lycium barbarum (LB) is a famous traditional Chinese medicinal plant as well as food supplement possessing various pharmacological functions such as anti-aging and antioxidant effects. The Parkinson's disease (PD)-related kinase Pink1 plays vital role in maintaining the neuron cell homeostasis, having been recognized as a potential target for the development of anti-PD drugs. In this work, the neuroprotective effects of methanol extract of LB fruit (LBFE) were investigated using a Drosophila PD model (PINK1B9) and a human neuroblastoma SH-SY5Y cell line. We found that when LBFE was supplied to the PINK1B9 flies at 6, 12, and 18 days of age, it raised the ATP and dopamine levels at all ages, extended life span, improved motor behavior, and rescued olfactory deficits of the PINK1B9 flies. In addition, histopathological examinations indicated that muscle atrophy in thoraces of the mutant flies was significantly repaired. Finally, LBFE was able to rescue the SH-SY5Y cells against MPP+-induced neurotoxicity. This work reports for the first time the anti-PD potential of L. barbarum fruit extract in PINK1 mutant fruit flies, presenting a new viewpoint for studing the mechanism of action of LBFE.


Assuntos
Proteínas de Drosophila , Lycium , Neuroblastoma , Fármacos Neuroprotetores , Doença de Parkinson , Animais , Humanos , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Doença de Parkinson/genética , Fármacos Neuroprotetores/farmacologia , Lycium/metabolismo , Modelos Genéticos , Extratos Vegetais/farmacologia , Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/farmacologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/farmacologia
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(6): 1011-1014, 2023 Dec 30.
Artigo em Chinês | MEDLINE | ID: mdl-38173115

RESUMO

One case with ascites and lower limb edema as the initial manifestations was reported.The echocardiography revealed inferior vena cava and right atrial occupation,which combined with increased alpha fetoprotein and imaging examination,suggested liver malignant tumor combined with tumor thrombus of inferior vena cava and right atrium.After targeted therapy combined with immunotherapy,the tumor shrank and alpha fetoprotein decreased significantly,suggesting that the treatment was effective.The median survival time of the patient was 3 months.This patient had a clear history of cirrhosis due to hepatitis B and was clinically diagnosed with advanced liver cancer,which suggested the importance of early liver cancer screening.


Assuntos
Neoplasias Hepáticas , Veia Cava Inferior , Humanos , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/patologia , alfa-Fetoproteínas , Ecocardiografia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Neoplasias Hepáticas/patologia
5.
J Phys Condens Matter ; 34(43)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35985316

RESUMO

Electronic band structure and optical conductivity of single-layer graphene could be altered by applied uniaxial strain. Valley and space inversion symmetries are broken. Dirac cones are deformed. We investigate the effect of uniaxial strain on the radiative properties of graphene from the perspective of direction and modulus. Optical conductivity exhibits wealthy phenomenon due to the degeneracy of the energy band broken by strain. The total energy radiation exhibits a novel behavior of periodicity inθ, in accordance with the symmetry of the hexagonal honeycomb lattice.

6.
CNS Neurosci Ther ; 28(9): 1393-1408, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35702948

RESUMO

AIMS: Visceral hypersensitivity in irritable bowel syndrome (IBS) is widespread, but effective therapies for it remain elusive. As a canonical anti-inflammatory protein, suppressor of cytokine signaling 3 (SOCS3) reportedly relays exchange protein 1 directly activated by cAMP (Epac1) signaling and inhibits the intracellular response to inflammatory cytokines. Despite the inhibitory effect of SOCS3 on the pro-inflammatory response and neuroinflammation in PVN, the systematic investigation of Epac1-SOCS3 signaling involved in visceral hypersensitivity remains unknown. This study aimed to explore Epac1-SOCS3 signaling in the activity of hypothalamic paraventricular nucleus (PVN) corticotropin-releasing factor (CRF) neurons and visceral hypersensitivity in adult rats experiencing neonatal colorectal distension (CRD). METHODS: Rats were subjected to neonatal CRD to simulate visceral hypersensitivity to investigate the effect of Epac1-SOCS3 signaling on PVN CRF neurons. The expression and activity of Epac1 and SOCS3 in nociceptive hypersensitivity were determined by western blot, RT-PCR, immunofluorescence, radioimmunoassay, electrophysiology, and pharmacology. RESULTS: In neonatal-CRD-induced visceral hypersensitivity model, Epac1 and SOCS3 expressions were downregulated and IL-6 levels elevated in PVN. However, infusion of Epac agonist 8-pCPT in PVN reduced CRF neuronal firing rates, and overexpression of SOCS3 in PVN by AAV-SOCS3 inhibited the activation of PVN neurons, reduced visceral hypersensitivity, and precluded pain precipitation. Intervention with IL-6 neutralizing antibody also alleviated the visceral hypersensitivity. In naïve rats, Epac antagonist ESI-09 in PVN increased CRF neuronal firing. Consistently, genetic knockdown of Epac1 or SOCS3 in PVN potentiated the firing rate of CRF neurons, functionality of HPA axis, and sensitivity of visceral nociception. Moreover, pharmacological intervention with exogenous IL-6 into PVN simulated the visceral hypersensitivity. CONCLUSIONS: Inactivation of Epac1-SOCS3 pathway contributed to the neuroinflammation accompanied by the sensitization of CRF neurons in PVN, precipitating visceral hypersensitivity and pain in rats experiencing neonatal CRD.


Assuntos
Fatores de Troca do Nucleotídeo Guanina , Hiperalgesia , Enteropatias , Proteína 3 Supressora da Sinalização de Citocinas , Dor Visceral , Animais , Doenças do Colo/genética , Doenças do Colo/metabolismo , Doenças do Colo/patologia , Hormônio Liberador da Corticotropina/metabolismo , Dilatação Patológica/complicações , Dilatação Patológica/genética , Dilatação Patológica/metabolismo , Modelos Animais de Doenças , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Hiperalgesia/etiologia , Hiperalgesia/genética , Hiperalgesia/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Recém-Nascido , Doenças do Recém-Nascido/genética , Doenças do Recém-Nascido/metabolismo , Interleucina-6/metabolismo , Enteropatias/complicações , Enteropatias/genética , Enteropatias/metabolismo , Enteropatias/patologia , Doenças Neuroinflamatórias/genética , Doenças Neuroinflamatórias/metabolismo , Neurônios/metabolismo , Dor , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Sprague-Dawley , Doenças Retais/genética , Doenças Retais/metabolismo , Doenças Retais/patologia , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Dor Visceral/etiologia , Dor Visceral/genética , Dor Visceral/metabolismo
7.
J Psychopharmacol ; 35(5): 591-605, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33749357

RESUMO

BACKGROUND: Long-term morphine use is associated with serious side effects, such as morphine-induced hyperalgesia and analgesic tolerance. Previous investigations have documented the association between dopamine (DA) neurons in the ventral tegmental area (VTA) and pain. However, whether VTA DA neurons are implicated in morphine-induced hyperalgesia and analgesic tolerance remains elusive. METHODS: Initially, we observed behavioural effects of lidocaine administration into VTA or ablation of VTA DA neurons on morphine-induced hyperalgesia and anti-nociceptive tolerance. Subsequently, c-Fos expression in nucleus accumbens (NAc) shell-projecting and medial prefrontal cortex (mPFC)-projecting VTA DA neurons after chronic morphine treatment was respectively investigated. Afterwards, the effects of chemogenetic manipulation of NAc shell-projecting or mPFC-projecting DA neurons on morphine-induced hyperalgesia and anti-nociceptive tolerance were observed. Additionally, effects of chemogenetic manipulation of VTA GABA neurons on c-Fos expression in VTA DA neurons were investigated. RESULTS: Lidocaine injection into VTA relieved established hyperalgesia and anti-nociceptive tolerance whereas ablation of VTA DA neurons prevented the development of morphine-induced hyperalgesia and anti-nociceptive tolerance. Chronic morphine treatment increased c-Fos expression in NAc shell-projecting DA neurons, rather than in mPFC-projecting DA neurons. Chemogenetic manipulation of NAc shell-projecting DA neurons had influence on morphine-induced hyperalgesia and tolerance. However, chemogenetic manipulation of mPFC-projecting DA neurons had no significant effects on morphine-induced hyperalgesia and anti-nociceptive tolerance. Chemogenetic manipulation of VTA GABA neurons affected the c-Fos expression in VTA DA neurons. CONCLUSIONS: These findings revealed the involvement of NAc shell-projecting VTA DA neurons in morphine-induced hyperalgesia and anti-nociceptive tolerance, and may shed new light on the clinical management of morphine-induced hyperalgesia and analgesic tolerance. PERSPECTIVE: This study demonstrated that NAc shell-projecting DA neurons rather than mPFC-projecting DA neurons in the VTA were implicated in morphine-induced hyperalgesia and anti-nociceptive tolerance. Our findings may pave the way for the discovery of novel therapies for morphine-induced hyperalgesia and analgesic tolerance.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Tolerância a Medicamentos , Hiperalgesia/induzido quimicamente , Morfina/toxicidade , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacologia , Analgésicos Opioides/toxicidade , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Morfina/administração & dosagem , Morfina/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo
8.
J Phys Condens Matter ; 33(5)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33017806

RESUMO

We investigate the radiation of energy and angular momentum from 2D topological systems with broken inversion symmetry and time reversal symmetry. A general theory of far-field radiation is developed using the linear response of 2D materials to the thermal fluctuation of electric currents. Applying the theory to the Haldane model, we verify that the heat radiation complies with Planck's law only at low temperature and deviates from it as temperature becomes high. In contrast to normal metals, angular momentum radiation is possible for this system and exhibits saturation as temperature increases. Parameters crucial to the radiation are investigated and optimized. This research enlightens the possibility of transposing the quantum information to the angular momentum degree of freedom.

9.
J Inflamm (Lond) ; 17: 12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32127783

RESUMO

BACKGROUND: Inflammatory molecular signals are modulated by a variety of intracellular transduction pathways, the activation of which may induce and amplify the spread of inflammatory response. Suppresser of cytokine signaling 3 (SOCS3) is an established negative feedback regulation transcription factor associated with tumor, diabetes mellitus, inflammation and anaphylaxis. Herein, we investigated whether SOCS3 in the paraventricular nucleus (PVN) can attenuate pro-inflammatory responses, and thereby relieve the inflammatory pain. METHODS: Adeno-associated virus (AAV) overexpressing SOCS3 was pre-injected into the PVN. Three weeks later, rat model of chronic inflammatory pain was established via subcutaneous injection of complete Freund's adjuvant (CFA) into the plantar center of hind paws. The therapeutic effect of SOCS3 was tested by the measurement of thermal and mechanical allodynia. In mechanistic study, the protein level of SOCS3 was evaluated by Western blotting, and the expression of c-fos and Iba-1 were assessed by immunofluorescent staining. RESULTS: Inflammatory pain was associated with upregulated interleukin 6 (IL-6) and SOCS3 in PVN in the acute phase. Thermal hyperalgesia can be relieved by intra-PVN injection of IL-6 neutralizing antibody (NA). Meanwhile, the upregulated c-fos and microglial activation was reversed. Furthermore, SOCS3 expression in PVN was downregulated in the chronic phase. Intra-PVN injection of AAV overexpressing SOCS3 suppressed the activation of neurons and attenuated thermal hyperalgesia and mechanical allodynia. CONCLUSION: Inhibition of IL-6 signaling attenuated inflammatory hyperalgesia in the acute phase. SOCS3 overexpression in the PVN attenuated inflammatory pain in the chronic phase via suppression of neuronal activation.

10.
Front Pharmacol ; 10: 1569, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038246

RESUMO

Cigarette smoking or nicotine exposure during pregnancy is associated with numerous obstetrical, fetal, and developmental complications, as well as an increased risk of adverse health consequences in the adult offspring. In this study, we examined the effects of maternal nicotine exposure during perinatal and lactation stages on behavioral performance and hippocampal neurogenesis in the adolescent stage of offspring mice. Female C57BL/mice received nicotine in drinking water (200 µg/ml nicotine) or vehicle (1% saccharin) starting from 2 weeks premating until the offspring were weaned on postnatal day 20. Experiments started on postnatal day 35. Female offspring with maternal nicotine exposure presented an increase in anxiety-like behavior in an open-field test. BrdU assay revealed that nicotine offspring presented an increase in cell proliferation in hippocampal dentate gyrus, but the number of BrdU+ cells was decreased in one week and further decreased in three weeks. The occurrence of disarray of DCX+ cells increased in both male and female nicotine offspring. The density of microglial marker protein Iba1 was significantly increased in the nicotine offspring. Furthermore, the expression of microglia marker Iba1, the CX3CL1, CX3CR1, and downstream molecules PKA and p-ErK were significantly increased in the nicotine group. In summary, maternal nicotine exposure affects both hippocampal neurogenesis and microglial activity in the adolescent offspring.

11.
Hepatol Res ; 48(3): E133-E145, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28707778

RESUMO

AIM: Chronic hepatitis B (CHB) patients with normal alanine aminotransferase (ALT) levels are not free from significant hepatic lesions. Recently, there has been an improved understanding of the clinical significance of quantitative hepatitis B core antibody levels (qAnti-HBc) during CHB management. In this cross-sectional study, we evaluated the utility of qAnti-HBc in identifying significant liver inflammation in CHB patients. METHODS: A total of 469 patients (training set, n = 363; validation set, n = 106) who underwent liver biopsy (LB) were included. The qAnti-HBc levels were quantified and the relationship between histology and serum markers was systematically analyzed. RESULTS: In the training set, qAnti-HBc levels were found to have significant diagnostic value for moderate to severe liver inflammation (≥G2) in all patients (area under the receiver operating characteristic curve [AUROC] = 0.768; 95% confidence interval [CI], 0.721-0.810; P < 0.001) and in patients with normal or near-normal ALT levels (AUROC = 0.767; 95% CI, 0.697-0.828; P < 0.001). Our novel index (AC index) for the identification of ≥G2 inflammation, which combined the qAnti-HBc and ALT levels, significantly improved diagnostic performance (AUROC = 0.813; 95% CI, 0.768-0.852) compared to the use of ALT alone (AUROC = 0.779; 95% CI, 0.732-0.821) in all patients. In the validation set, the AC index showed an improved AUROC of 0.890 (95% CI, 0.814-0.942) and 0.867 (95% CI, 0.749-0.943) in all patients and patients with normal ALT levels, respectively. CONCLUSIONS: The qAnti-HBc level predicts significant liver inflammation well, even in patients with normal or near-normal ALT levels. Compared with the conventional ALT level, the AC index is a more reliable non-invasive biomarker for significant liver inflammation in CHB patients.

12.
Neuromolecular Med ; 19(4): 541-554, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28916896

RESUMO

The pro-inflammatory activity of interleukin 17, which is produced by the IL-23/IL-17 axis, has been associated with the pathogenesis of traumatic brain injury (TBI). The study investigated the potential role of IL-17 in secondary brain injury of TBI in a rat model. Our data showed that the levels of IL-17 increased from 6 h to 7 days and peaked at 3 days, in both the CNS and serum, which were consistent with the severity of secondary brain injury. The IL-23 inhibitor suberoylanilide hydroxamic acid (SAHA) treatment markedly decreased the expressions of IL-17 and apoptosis-associated proteins cleaved caspase-3 and increased the protein ratio of Bcl-2 (B cell lymphoma/leukemia-2)/Bax (Bcl-2-associated X protein). Meanwhile, neuronal apoptosis was reduced, and neural function was improved after SAHA treatment. This study suggests that IL-17 is involved in secondary brain injury after TBI. Administering an IL-23 inhibitor and thereby blocking the IL-23/IL-17 axis may be beneficial in the treatment of TBI.


Assuntos
Dano Encefálico Crônico/fisiopatologia , Lesões Encefálicas Traumáticas/fisiopatologia , Interleucina-17/fisiologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/metabolismo , Dano Encefálico Crônico/prevenção & controle , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico , Inflamação , Interleucina-17/sangue , Interleucina-17/líquido cefalorraquidiano , Interleucina-17/genética , Interleucina-23/antagonistas & inibidores , Interleucina-23/fisiologia , Masculino , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/sangue , Proteínas do Tecido Nervoso/líquido cefalorraquidiano , Proteínas do Tecido Nervoso/genética , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Vorinostat
13.
Front Pharmacol ; 8: 309, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28611665

RESUMO

Neonatal maternal separation (MS) is a major early life stress that increases the risk of emotional disorders, visceral pain perception and other brain dysfunction. Elevation of toll-like receptor 4 (TLR4) signaling in the paraventricular nucleus (PVN) precipitates early life colorectal distension (CRD)-induced visceral hypersensitivity and pain in adulthood. The present study aimed to investigate the role of TLR4 signaling in the pathogenesis of postnatal MS-induced visceral hypersensitivity and pain during adulthood. The TLR4 gene was selectively knocked out in C57BL/10ScSn mice (Tlr4-/-). MS was developed by housing the offspring alone for 6 h daily from postnatal day 2 to day 15. Visceral hypersensitivity and pain were assessed in adulthood. Tlr4+/+, but not Tlr4-/-, mice that had experienced neonatal MS showed chronic visceral hypersensitivity and pain. TLR4 immunoreactivity was observed predominately in microglia in the PVN, and MS was associated with an increase in the expression of protein and/or mRNA levels of TLR4, corticotropin-releasing factor (CRF), CRF receptor 1 (CRFR1), tumor necrosis factor-α, and interleukin-1ß in Tlr4+/+ mice. These alterations were not observed in Tlr4-/- mice. Local administration of lipopolysaccharide, a TLR4 agonist, into the lateral cerebral ventricle elicited visceral hypersensitivity and TLR4 mRNA expression in the PVN, which could be prevented by NBI-35965, an antagonist to CRFR1. The present results indicate that neonatal MS induces a sensitization and upregulation of microglial TLR4 signaling activity, which facilitates the neighboring CRF neuronal activity and, eventually, precipitates visceral hypersensitivity in adulthood. Highlights (1)Neonatal MS does not induce chronic visceral hypersensitivity and pain in Tlr4-/- mice.(2)Neonatal MS increases the expression of TLR4 mRNA, CRF protein and mRNA, CRFR1 protein, TNF-α protein, and IL-1ß protein in Tlr4+/+ mice.(3)TLR4 agonist LPS (i.c.v.) elicits visceral hypersensitivity and TLR4 mRNA expression in the PVN.

14.
Artigo em Inglês | MEDLINE | ID: mdl-27821444

RESUMO

Penicillin-binding proteins (PBPs) function as transpeptidases, carboxypeptidases, or endopeptidases during peptidoglycan synthesis in bacteria. As the well-known drug targets for ß-lactam antibiotics, the physiological functions of PBPs and whether they are essential for growth are of significant interest. The pathogen Pseudomonas aeruginosa poses a particular risk to immunocompromised and cystic fibrosis patients, and infections caused by this pathogen are difficult to treat due to antibiotic resistance. To identify potential drug targets among the PBPs in P. aeruginosa, we performed gene knockouts of all the high-molecular-mass (HMM) PBPs and determined the impacts on cell growth and morphology, susceptibility to ß-lactams, peptidoglycan structure, virulence, and pathogenicity. Disruptions of the transpeptidase domains of most HMM PBPs, including double disruptions, had only minimal effects on cell growth. The exception was PBP3, where cell growth occurred only when the protein was conditionally expressed on an integrated plasmid. Conditional deletion of PBP3 also caused a defect in cell division and increased susceptibility to ß-lactams. Knockout of PBP1a led to impaired motility, and this observation, together with its localization at the cell poles, suggests its involvement in flagellar function. Overall, these findings reveal that PBP3 represents the most promising target for drug discovery against P. aeruginosa, whereas other HMM PBPs have less potential.


Assuntos
Proteínas de Ligação às Penicilinas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Ligação às Penicilinas/genética , Peptidoglicano/farmacologia , Pseudomonas aeruginosa/genética , beta-Lactamas/farmacologia
15.
Front Pharmacol ; 7: 138, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27303299

RESUMO

A number of acute or repeated stimuli can induce expression of DeltaFosB (ΔFosB), a transcription factor derived from the fosB gene (an osteosarcoma viral oncogene) via alternative splicing. ΔFosB protein is currently viewed as a 'molecular switch' to repeated stimuli that gradually converts acute responses into relatively stable adaptations underlying long-term neural and behavioral plasticity. ΔFosB has received extensive attention in drug addition, depression, and stress adaptation, but changes in ΔFosB protein expression during pain is not fully understood. In this study we explored ΔFosB expression in the medial prefrontal cortex (mPFC) of rats experiencing chronic or acute stress-induced pain. Our data reveal that chronic pain induced by neonatal colorectal distension, chronic constriction injury (CCI) of the sciatic nerve, or maternal separation was associated with an increase in ΔfosB protein expression in mPFC, but acute application of acetic acid or zymosan did not alter the ΔFosB protein expression. ΔFosB expression in the rat visual cortex, a non pain-related brain region, did not change in response to (CCI) of the sciatic nerve and acetic acid treatment. In conclusion, our results indicate that ΔFosB protein expression is significantly elevated in rats that have experienced chronic pain and stress, but not acute pain. The ΔFosB protein may serve as an important transcription factor for chronic stress-induced pain. Further research is needed to improve the understanding of both the upstream signaling leading to ΔFosB protein expression as well as the regulation of ΔFosB gene expression in cortical neurons.

16.
J Med Chem ; 59(7): 3140-51, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26964758

RESUMO

Antibiotic resistance is a growing threat to human health exacerbated by a lack of new antibiotics. We now describe a series of substituted diamines that produce rapid bactericidal activity against both Gram-positive and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus and stationary-phase bacteria. These compounds reduce biofilm formation and promote biofilm dispersal in Pseudomonas aeruginosa. The most potent analogue, 3 (1,13-bis{[(2,2-diphenyl)-1-ethyl]thioureido}-4,10-diazatridecane), primarily acts by depolarization of the cytoplasmic membrane and permeabilization of the bacterial outer membrane. Transmission electron microscopy confirmed that 3 disrupts membrane integrity rapidly. Compound 3 is also synergistic with kanamycin, demonstrated by the checkerboard method and by time-kill kinetic experiments. In human cell toxicity assays, 3 showed limited adverse effects against the HEK293T human kidney embryonic cells and A549 human adenocarcinoma cells. In addition, 3 produced no adverse effects on Caenorhabditis elegans development, survival, and reproduction. Collectively, diamines related to 3 represent a new class of broad-spectrum antibacterials against drug-resistant pathogens.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Membrana Celular/efeitos dos fármacos , Diaminas/química , Animais , Antibacterianos/efeitos adversos , Biofilmes/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/crescimento & desenvolvimento , Permeabilidade da Membrana Celular/efeitos dos fármacos , Técnicas de Química Sintética , Diaminas/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Interações Medicamentosas , Escherichia coli/efeitos dos fármacos , Células HEK293/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
17.
PeerJ ; 4: e1495, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26788419

RESUMO

Bacteria synchronize group behaviors using quorum sensing, which is advantageous during an infection to thwart immune cell attack and resist deleterious changes in the environment. In Pseudomonas aeruginosa, the Pseudomonas quinolone signal (Pqs) quorum-sensing system is an important component of an interconnected intercellular communication network. Two alkylquinolones, 2-heptyl-4-quinolone (HHQ) and 2-heptyl-3-hydroxy-4-quinolone (PQS), activate transcriptional regulator PqsR to promote the production of quinolone signals and virulence factors. Our work focused on the most abundant quinolone produced from the Pqs system, 2,4-dihydroxyquinoline (DHQ), which was shown previously to sustain pyocyanin production and antifungal activity of P. aeruginosa. However, little is known about how DHQ affects P. aeruginosa pathogenicity. Using C. elegans as a model for P. aeruginosa infection, we found pqs mutants only able to produce DHQ maintained virulence towards the nematodes similar to wild-type. In addition, DHQ-only producing mutants displayed increased colonization of C. elegans and virulence factor production compared to a quinolone-null strain. DHQ also bound to PqsR and activated the transcription of pqs operon. More importantly, high extracellular concentration of DHQ was maintained in both aerobic and anaerobic growth. High levels of DHQ were also detected in the sputum samples of cystic fibrosis patients. Taken together, our findings suggest DHQ may play an important role in sustaining P. aeruginosa pathogenicity under oxygen-limiting conditions.

18.
Brain Behav Immun ; 55: 93-104, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26743854

RESUMO

Visceral hypersensitivity is a major contributor to irritable bowel syndrome and other disorders with visceral pain. Substantial evidence has established that glial activation and neuro-glial interaction play a key role in the establishment and maintenance of visceral hypersensitivity. We recently demonstrated that activation of spinal microglial toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor κB (NF-κB) signaling facilitated the development of visceral hypersensitivity in a rat model developed by neonatal and adult colorectal distensions (CRDs). Hypothalamic paraventricular nucleus (PVN) plays a pivotal role in the pathogenesis of chronic pain. In this study, we examined the mechanism by which microglia and neurons in PVN establish and maintain visceral hypersensitivity and the involvement of TLR4 signaling. Visceral hypersensitivity was precipitated by adult colorectal distension (CRD) only in rats that experienced neonatal CRDs. Visceral hypersensitivity was associated with an increase in the expression of c-fos, corticotropin-releasing factor (CRF) protein and mRNA in PVN, which could be prevented by intra-PVN infusion of lidocaine or small interfering RNA targeting the CRF gene. These results suggest PVN CRF neurons modulate visceral hypersensitivity. Adult CRD induced an increase in the expression of Iba-1 (a microglial marker), TLR4 protein, and its downstream effectors MyD88, NF-κB, as well as proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) only in rats that experienced neonatal CRDs. Intra-PVN infusion of minocycline, a nonselective microglial inhibitor, attenuated the hyperactivity of TLR4 signaling cascade, microglial activation, and visceral hypersensitivity. Taken together, these data suggest that neonatal CRDs induce a glial activation in PVN. Adult CRD potentiates the glial and CRF neuronal activity, and precipitates visceral hypersensitivity and pain. TLR4 signaling and proinflammatory cytokines TNF-α and IL-1ß may participate in neuro-glial interaction during the pathogenesis of visceral hypersensitivity.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Síndrome do Intestino Irritável/metabolismo , Microglia/metabolismo , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Receptor 4 Toll-Like/metabolismo , Dor Visceral/metabolismo , Animais , Colo/fisiopatologia , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Reto/fisiopatologia
19.
Neuropharmacology ; 102: 295-303, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26656865

RESUMO

Visceral hypersensitivity is a common characteristic in patients suffering from irritable bowel syndrome (IBS) and other disorders with visceral pain. Although the pathogenesis of visceral hypersensitivity remains speculative due to the absence of pathological changes, the long-lasting sensitization in neuronal circuitry induced by early life stress may play a critical role beyond the digestive system even after complete resolution of the initiating event. The hippocampus integrates multiple sources of afferent inputs and sculpts integrated autonomic outputs for pain and analgesia regulation. Here, we examined the hippocampal mechanism in the pathogenesis of visceral hypersensitivity with a rat model induced by neonatal and adult colorectal distensions (CRDs). Neither neonatal nor adult CRD evoked behavioral abnormalities in adulthood; however, adult re-exposure to CRD induced persistent visceral hypersensitivity, depression-like behaviors, and spatial learning impairment in rats that experienced neonatal CRD. Rats that experienced neonatal and adult CRDs presented a decrease in hippocampal glucocorticoid receptor (GR) immunofluorescence staining and protein expression, and increases in hippocampal microglial activation and cytokine (IL-1ß and TNF-α) accumulation. The decrease in hippocampal GR expression and increase in hippocampal IL-1ß and TNF-α accumulation could be prevented by hippocampal local infusion of minocycline, a microglial inhibitor. These results suggest that neonatal CRD can increase the vulnerability of hippocampal microglia, and adult CRD challenge facilitates the hippocampal cytokine release from the sensitized microglia, which down-regulates hippocampal GR protein expression and, subsequently, precipitates visceral hypersensitivity.


Assuntos
Hipocampo/metabolismo , Microglia/metabolismo , Receptores de Glucocorticoides/metabolismo , Dor Visceral/metabolismo , Animais , Colo/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Interleucina-1beta/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/genética , Reto/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Dor Visceral/etiologia
20.
World J Gastroenterol ; 21(21): 6639-48, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-26074702

RESUMO

AIM: To investigate precore/basal core promoter (PC/BCP) mutants throughout hepatitis B virus (HBV) infection and to determine their relationship to hepatitis B early antigen (HBeAg) titers. METHODS: We enrolled 191 patients in various stages of HBV infection at the Huashan Hospital and the Taizhou Municipal Hospital from 2010 to 2012. None of the patients received antiviral therapy. HBV DNA from serum, was quantified by real-time PCR. The HBV genotype was determined by direct sequencing of the S gene. We used the Simpleprobe ultrasensitive quantitative method to detect PC/BCP mutants in each patient. We compared the strain number, percentage, and the changes in PC/BCP mutants in different phases, and analyzed the relationship between PC/BCP mutants and HBeAg by multiple linear regression and logistic regression. RESULTS: Patients with HBV infection (n = 191) were assigned to groups by phase: Immune tolerance (IT) = 55, Immune clearance (IC) = 67, Low-replicative (LR) = 49, and HBeAg-negative hepatitis (ENH) = 20. Of the patients (male, 112; female, 79) enrolled, 122 were HBeAg-positive and 69 were HBeAg-negative. The median age was 33 years (range: 18-78 years). PC and BCP mutation detection rates were 84.82% (162/191) and 96.86% (185/191), respectively. In five HBeAg-negative cases, we detected double mutation G1896A/G1899A. The logarithm value of PC mutant quantities (log10 PC) significantly differed in IT, IC, and LR phases, as well as in the ENH phase (F = 49.350, P < 0.001). The logarithm value of BCP mutant quantities (log10 BCP) also differed during the four phases (F = 25.530, P < 0.001). Log10 PC and log10 BCP values were high in the IT and IC phases, decreased in the LR phase, and increased in the ENH phase, although the absolute value at this point remained lower than that in the IT and IC phases. PC mutant quantity per total viral load (PC%) and BCP mutant quantity per total viral load (BCP%) differed between phases (F = 20.040, P < 0.001; F = 10.830, P < 0.001), with PC% and BCP% gradually increasing in successive phases. HBeAg titers negatively correlated with PC% (Spearman's rho = -0.354, P < 0.001) and BCP% (Spearman's rho = -0.395, P < 0.001). The negative correlation between PC% and HBeAg status was significant (B = -5.281, P = 0.001), but there was no such correlation between BCP% and HBeAg status (B = -0.523, P = 0.552). CONCLUSION: PC/BCP mutants become predominant in a dynamic and continuous process. Log10 PC, log10 BCP, PC% and BCP% might be combined to evaluate disease progression. PC% determines HBeAg status.


Assuntos
Análise Mutacional de DNA/métodos , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Mutação , Proteínas do Core Viral/genética , Adolescente , Adulto , Idoso , Biomarcadores/sangue , China , DNA Viral/sangue , Progressão da Doença , Feminino , Genótipo , Hepatite B/sangue , Hepatite B/diagnóstico , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/imunologia , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Carga Viral , Adulto Jovem
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