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1.
Eur J Obstet Gynecol Reprod Biol ; 294: 123-127, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38237310

RESUMO

OBJECTIVE: This study evaluated embryological and clinical outcomes in couples with severe male factor infertility versus those with normozoospermia undergoing ICSI and in vitro fertilisation. METHODS: This multicentre, retrospective cohort study included all couples who had undergone autologous ICSI cycles at My Duc Hospital and My Duc Phu Nhuan Hospital in Vietnam between January 2018 and January 2021 (female age < 35 years and males with severe male factor or normozoospermia based on the World Health Organization 2010 criteria). The primary outcome was the cumulative live birth rate after the first ICSI cycle. RESULTS: A total of 1296 couples were included, including 648 with severe male factor infertility and 648 with normozoospermia. The number of two pronuclei zygotes, embryos, and frozen embryos was significantly lower in couples with severe male factor infertility compared with normozoospermia (p < 0.05). In contrast, there were no significant differences between the two groups with respect to cumulative pregnancy outcomes, including the live birth rate, and secondary outcomes including clinical pregnancy rate, ongoing pregnancy rate, and miscarriage rate. CONCLUSION: Severe male factor infertility appeared to have an impact on the fertilisation and early developmental potential of embryos, but sperm quality did not affect cumulative clinical fertility outcomes.


Assuntos
Infertilidade Masculina , Infertilidade , Gravidez , Masculino , Humanos , Feminino , Adulto , Injeções de Esperma Intracitoplásmicas/métodos , Estudos Retrospectivos , Sêmen , Infertilidade Masculina/terapia , Fertilização in vitro/métodos , Taxa de Gravidez , Coeficiente de Natalidade , Nascido Vivo
2.
Front Bioeng Biotechnol ; 11: 1236429, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094898

RESUMO

Micron-scale structure biphasic calcium phosphate (BCP) materials have demonstrated promising clinical outcomes in the field of bone tissue repair. However, research on biphasic calcium phosphate materials at the nanoscale level remains limited. In this study, we synthesize granular-shaped biphasic calcium phosphate nanomaterials with multiple desirable characteristics, including negatively charged surfaces, non-cytotoxicity, and the capability to penetrate cells, using a nanogrinding dispersion process with a polymeric carboxylic acid as the dispersant. Our results reveal that treating human osteoblasts with 0.5 µg/mL biphasic calcium phosphate nanomaterials results in a marked increase in alkaline phosphatase (ALP) activity and the upregulation of osteogenesis-related genes. Furthermore, these biphasic calcium phosphate nanomaterials exhibit immunomodulatory properties. Treatment of THP-1-derived macrophages with BCP nanomaterials decreases the expression of various inflammatory genes. Biphasic calcium phosphate nanomaterials also mitigate the elevated inflammatory gene expression and protein production triggered by lipopolysaccharide (LPS) exposure in THP-1-derived macrophages. Notably, we observe that biphasic calcium phosphate nanomaterials have the capacity to reverse the detrimental effects of LPS-stimulated macrophage-conditioned medium on osteoblastic activity and mineralization. These findings underscore the potential utility of biphasic calcium phosphate nanomaterials in clinical settings for the repair and regeneration of bone tissue. In conclusion, this study highlights the material properties and positive effects of biphasic calcium phosphate nanomaterials on osteogenesis and immune regulation, opening a promising avenue for further research on inflammatory osteolysis in patients undergoing clinical surgery.

3.
Cell Death Discov ; 9(1): 340, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696858

RESUMO

The tumor suppressor p53 primarily functions as a mediator of DNA damage-induced cell death, thereby contributing to the efficacy of genotoxic anticancer therapeutics. Here, we show, on the contrary, that cancer cells can employ genotoxic stress-induced p53 to acquire treatment resistance through the production of the pleiotropic cytokine interleukin (IL)-6. Mechanistically, DNA damage, either repairable or irreparable, activates p53 and stimulates Caspase-2-mediated cleavage of its negative regulator mouse double minute 2 (MDM2) creating a positive feedback loop that leads to elevated p53 protein accumulation. p53 transcriptionally controls the major adenosine triphosphate (ATP) release channel pannexin 1 (Panx1), which directs IL-6 induction via a mechanism dependent on the extracellular ATP-activated purinergic P2 receptors as well as their downstream intracellular calcium (iCa2+)/PI3K/Akt/NF-ĸB signaling pathway. Thus, p53 silencing impairs Panx1 and IL-6 expression and renders cancer cells sensitive to genotoxic stress. Moreover, we confirm that IL-6 hampers the effectiveness of genotoxic anticancer agents by mitigating DNA damage, driving the expression of anti-apoptotic Bcl-2 family genes, and maintaining the migratory and invasive properties of cancer cells. Analysis of patient survival and relevant factors in lung cancer and pan-cancer cohorts supports the prognostic and clinical values of Panx1 and IL-6. Notably, IL-6 secreted by cancer cells during genotoxic treatments promotes the polarization of monocytic THP-1-derived macrophages into an alternative (M2-like) phenotype that exhibits impaired anti-survival activities but enhanced pro-metastatic effects on cancer cells as compared to nonpolarized macrophages. Our study reveals the precise mechanism for genotoxic-induced IL-6 and suggests that targeting p53-mediated IL-6 may improve the responsiveness of cancer cells to genotoxic anticancer therapy.

4.
Redox Biol ; 64: 102791, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385076

RESUMO

Snake venom l-amino acid oxidases (svLAAOs) have been recognized as promising candidates for anticancer therapeutics. However, multiple aspects of their catalytic mechanism and the overall responses of cancer cells to these redox enzymes remain ambiguous. Here, we present an analysis of the phylogenetic relationships and active site-related residues among svLAAOs and reveal that the previously proposed critical catalytic residue His 223 is highly conserved in the viperid but not the elapid svLAAO clade. To gain further insight into the action mechanism of the elapid svLAAOs, we purify and characterize the structural, biochemical, and anticancer therapeutic potentials of the Thailand elapid snake Naja kaouthia LAAO (NK-LAAO). We find that NK-LAAO, with Ser 223, exhibits high catalytic activity toward hydrophobic l-amino acid substrates. Moreover, NK-LAAO induces substantial oxidative stress-mediated cytotoxicity with the magnitude relying on both the levels of extracellular hydrogen peroxide (H2O2) and intracellular reactive oxygen species (ROS) generated during the enzymatic redox reactions, but not being influenced by the N-linked glycans on its surface. Unexpectedly, we discover a tolerant mechanism deployed by cancer cells to dampen the anticancer activities of NK-LAAO. NK-LAAO treatment amplifies interleukin (IL)-6 expression via the pannexin 1 (Panx1)-directed intracellular calcium (iCa2+) signaling pathway to confer adaptive and aggressive phenotypes on cancer cells. Accordingly, IL-6 silencing renders cancer cells vulnerable to NK-LAAO-induced oxidative stress together with abrogating NK-LAAO-stimulated metastatic acquisition. Collectively, our study urges caution when using svLAAOs in cancer treatment and identifies the Panx1/iCa2+/IL-6 axis as a therapeutic target for improving the effectiveness of svLAAOs-based anticancer therapies.


Assuntos
Interleucina-6 , Neoplasias , Humanos , Interleucina-6/genética , L-Aminoácido Oxidase/química , L-Aminoácido Oxidase/metabolismo , L-Aminoácido Oxidase/farmacologia , Peróxido de Hidrogênio/metabolismo , Filogenia , Venenos de Serpentes , Neoplasias/tratamento farmacológico , Aminoácidos
5.
Oncogenesis ; 11(1): 26, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589683

RESUMO

Tumor suppressor p53 plays a central role in preventing tumorigenesis. Here, we unravel how p53 modulates mitochondrial dynamics to restrain the metastatic properties of cancer cells. p53 inhibits the mammalian target of rapamycin complex 1 (mTORC1) signaling to attenuate the protein level of mitochondrial fission process 1 (MTFP1), which fosters the pro-fission dynamin-related protein 1 (Drp1) phosphorylation. This regulatory mechanism allows p53 to restrict cell migration and invasion governed by Drp1-mediated mitochondrial fission. Downregulating p53 expression or elevating the molecular signature of mitochondrial fission correlates with aggressive tumor phenotypes and poor prognosis in cancer patients. Upon p53 loss, exaggerated mitochondrial fragmentation stimulates the activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling resulting in epithelial-to-mesenchymal transition (EMT)-like changes in cell morphology, accompanied by accelerated matrix metalloproteinase 9 (MMP9) expression and invasive cell migration. Notably, blocking the activation of mTORC1/MTFP1/Drp1/ERK1/2 axis completely abolishes the p53 deficiency-driven cellular morphological switch, MMP9 expression, and cancer cell dissemination. Our findings unveil a hitherto unrecognized mitochondria-dependent molecular mechanism underlying the metastatic phenotypes of p53-compromised cancers.

6.
Front Digit Health ; 4: 838590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35373184

RESUMO

Nanoparticles (NPs) hold great potential as therapeutics, particularly in the realm of drug delivery. They are effective at functional cargo delivery and offer a great degree of amenability that can be used to offset toxic side effects or to target drugs to specific regions in the body. However, there are many challenges associated with the development of NP-based drug formulations that hamper their successful clinical translation. Arguably, the most significant barrier in the way of efficacious NP-based drug delivery systems is the tedious and time-consuming nature of NP formulation-a process that needs to account for downstream effects, such as the onset of potential toxicity or immunogenicity, in vivo biodistribution and overall pharmacokinetic profiles, all while maintaining desirable therapeutic outcomes. Computational and AI-based approaches have shown promise in alleviating some of these restrictions. Via predictive modeling and deep learning, in silico approaches have shown the ability to accurately model NP-membrane interactions and cellular uptake based on minimal data, such as the physicochemical characteristics of a given NP. More importantly, machine learning allows computational models to predict how specific changes could be made to the physicochemical characteristics of a NP to improve functional aspects, such as drug retention or endocytosis. On a larger scale, they are also able to predict the in vivo pharmacokinetics of NP-encapsulated drugs, predicting aspects such as circulatory half-life, toxicity, and biodistribution. However, the convergence of nanomedicine and computational approaches is still in its infancy and limited in its applicability. The interactions between NPs, the encapsulated drug and the body form an intricate network of interactions that cannot be modeled with absolute certainty. Despite this, rapid advancements in the area promise to deliver increasingly powerful tools capable of accelerating the development of advanced nanoscale therapeutics. Here, we describe computational approaches that have been utilized in the field of nanomedicine, focusing on approaches for NP design and engineering.

7.
Metabolism ; 122: 154841, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34333001

RESUMO

Inherited metabolic disorders (IMDs) have been observed in individuals with hearing loss (HL), but IMDs are rarely the cause of syndromic HL. With early diagnosis, management of HL is more effective and cortical reorganization is possible with hearing aids or cochlear implants. This review describes relationships between IMDs and HL in terms of incidence, etiology of HL, pathophysiology, and treatment. Forty types of IMDs are described in the literature, mainly in case reports. Management and prognosis are noted where existing. We also describe IMDs with HL given age of occurrence of HL. Reviewing the main IMDs that are associated with HL may provide an additional clinical tool with which to better diagnose syndromic HL.


Assuntos
Perda Auditiva/diagnóstico , Perda Auditiva/patologia , Doenças Metabólicas/diagnóstico , Doenças Metabólicas/patologia , Animais , Implante Coclear/métodos , Surdez/complicações , Surdez/patologia , Auxiliares de Audição , Perda Auditiva/complicações , Humanos , Incidência , Doenças Metabólicas/etiologia
8.
Vet World ; 13(5): 896-904, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32636585

RESUMO

AIM: The study was conducted to determine the prevalence and characterization of the Pasteurella multocida isolates from suspected pigs in Vietnam. MATERIALS AND METHODS: A total of 83 P. multocida strains were isolated from lung samples and nasal swabs collected from pigs associated with pneumonia, progressive atrophic rhinitis, or reproductive and respiratory symptoms. Isolates were subjected to multiplex polymerase chain reaction (PCR) for capsular typing, detection of virulence-associated genes and antibiotic resistance genes by PCR. The antimicrobial sensitivity profiles of the isolates were tested by disk diffusion method. RESULTS: All the isolates 83/83 (100%) were identified as P. multocida by PCR: serogroup A was obtained from 40/83 (48.19%), serogroup D was detected from 24/83 strains (28.91%), and serogroup B was found in 19/83 (22.35%) isolates. The presence of 14 virulence genes was reported including adhesins group (ptfA - 93.97%, pfhA - 93.97%, and fimA - 90.36%), iron acquisition (exbB - 100%, and exbD - 85.54%), hyaluronidase (pmHAS - 84.33%), and protectins (ompA - 56.62%, ompH 68.67%, and oma87 - 100%). The dermonecrotoxin toxA had low prevalence (19.28%). The antimicrobial susceptibility testing revealed that cephalexin, cefotaxime, ceftriaxone, ofloxacin, pefloxacin, ciprofloxacin, and enrofloxacin were the drugs most likely active against P. multocida while amoxicillin and tetracycline were inactive. The usage of PCR revealed that 63/83 isolates were carrying at least one of the drug resistance genes. CONCLUSION: Unlike other parts of the word, serotype B was prevalent among Vietnamese porcine P. multocida strains. The high antibiotic resistance detected among these isolates gives us an alert about the current state of imprudent antibiotic usage in controlling the pathogenic bacteria.

9.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137(1): 13-16, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31564619

RESUMO

OBJECTIVE: Compared to canal wall up (CWU) tympanoplasty, canal wall reconstruction (CWR) allows better visualization of cholesteatoma extension. The canal wall up approach provides good functional outcomes, but with higher rates of residual cholesteatoma. The aim of this study was to compare residual cholesteatoma prevalence and location between the two approaches. METHOD: Subjects were adult patients with residual cholesteatoma following CWU or CWR surgery between January 1, 2010 and December 31, 2015. During this period, 94 patients underwent CWU and 71 CWR; 22 presented with residual cholesteatoma: 16 after CWU (R-CWU group) and 6 after CWR (R-CWR group). RESULTS: There was no significant inter-group difference in residual cholesteatoma prevalence: 17% after CWU, 8.4% after CWR. Locations comprised: 13 (81%) in the attic, 9 (56%) in the tympanic cavity and 4 (25%) in the mastoid in the R-CWU group, and 6 (100%) in the attic in the R-CWR group. There were significantly fewer tympanic cavity locations after CWR compared to CWU (P=0.046). CONCLUSION: Residual cholesteatoma prevalence did not significantly differ between the CWU and CWR approaches. The most frequent location was the attic; significantly more locations were in the tympanic cavity with the CWU approach. These findings are important for surgeons and neuro-radiologists during follow-up.


Assuntos
Colesteatoma da Orelha Média/cirurgia , Timpanoplastia/métodos , Adulto , Colesteatoma da Orelha Média/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
10.
11.
Gefasschirurgie ; 23(Suppl 2): 46-55, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30147244

RESUMO

INTRODUCTION: The Kerecis™ Omega3 Wound matrix is a decellularized skin matrix derived from fish skin and represents an innovative concept to achieve wound healing. The aim of this study was to report the cumulative experience of three centers for vascular surgery regarding use of the Omega3 Wound matrix in selected patients with complicated wounds. MATERIAL AND METHODS: In this study 23 patients with 25 vascular and/or diabetes mellitus-associated complicated wounds and partially exposed bony segments were treated with the Omega3 Wound matrix in three vascular centers. In several patients, conventional wound treatment with vacuum therapy had previously been carried out sometimes over several weeks without durable success. Following initial debridement in the operating room, the matrix was applied and covered with a silicone mesh. In the further course, wound treatment was conducted on an outpatient setting if possible. RESULTS: In total 25 wounds were treated with localization at the level of the thigh (n = 2), the distal calf (n = 7), the forefoot (n = 14) and the hand (n = 2). The time to heal varied between 9 and 41 weeks and between 3 and 26 wound matrices were applied per wound. Interestingly, a reduction of analgesics intake was noted when the treatment with the Omega3 Wound matrix was initiated. CONCLUSION: The novel Omega3 Wound matrix in this study represented an effective treatment option in 25 complicated wounds. Further studies are necessary to evaluate the impact of the wound matrix on stimulation of granulation tissue and re-epithelialization as well as the potential antinociceptive and analgetic effects.

12.
Clin Microbiol Infect ; 24(1): 84.e1-84.e4, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28780059

RESUMO

OBJECTIVES: Melioidosis may be endemic in many tropical developing countries, but diagnosis of the disease is currently unreliable in resource-limited areas. We aimed to validate a simple and cheap laboratory algorithm for the identification of Burkholderia pseudomallei from clinical specimens in parts of Vietnam where the disease has not previously been reported. METHODS: In June 2015, we conducted training courses at five general hospitals in north-central provinces in order to raise awareness of the disease and to introduce a simple and cheap laboratory identification algorithm for B. pseudomallei including the three-antibiotic disc test. RESULTS: Until the end of the year (7 months later), 94 suspected B. pseudomallei strains resistant to gentamicin and colistin but sensitive to amoxicillin/clavulanic acid were detected in clinical specimens from 70 patients. All strains were further confirmed as B. pseudomallei by using a specific TTSS1 real-time PCR assay and recA sequencing analysis. Among positive blood cultures, positive rates with B. pseudomallei ranged from 3.4% (5/147) to 10.2% (32/312) in the various clinics. A total of 82.8% (58/70) patients were bacteraemic, with a mortality of 50% (18/36) among patients with known outcome. No death occurred in nonbacteraemic patients. CONCLUSIONS: Our results demonstrate that the introduction of a simple and easy-to-perform laboratory algorithm for the identification of B. pseudomallei from clinical samples, together with clinical awareness raising, can lead to the diagnosis of a significant number of melioidosis cases in resource-limited clinical laboratories which previously did not identify the pathogen.


Assuntos
Algoritmos , Técnicas de Tipagem Bacteriana/métodos , Hemocultura/métodos , Burkholderia pseudomallei/isolamento & purificação , Melioidose/diagnóstico , Amoxicilina/farmacologia , Antibacterianos/farmacologia , Ácido Clavulânico/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana Múltipla , Quimioterapia Combinada , Feminino , Gentamicinas/farmacologia , Humanos , Masculino , Melioidose/microbiologia , Melioidose/mortalidade , Recombinases Rec A/genética , Vietnã
13.
Tech Coloproctol ; 21(3): 225-232, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28251355

RESUMO

BACKGROUND: There is no consensus on the treatment and prognosis of malignant rectal polyps. The aim of the present study was to determine the role of transanal endoscopic microsurgery (TEM) after endoscopic complete polypectomy of malignant rectal adenomas with long-term follow-up. METHODS: Of 105 patients with pT1 rectal carcinoma in 32 patients TEM followed complete endoscopic polypectomy while 73 had primary TEM. Local recurrence (LR), distant metastasis, overall and cancer-specific survival were determined by the Kaplan-Meier method. RESULTS: Median follow-up was 9.1 years. In 32 patients with TEM following complete polypectomy no residual cancer was found. LR occurred in 3/28 (11%) patients with low-risk carcinoma (pT1 G1/2/X, L0/X, R0) and in 1/4 (25%) with high-risk carcinoma (pT1 G3/4 or L1). After primary TEM with complete resection (minimal distance >1 mm) LR occurred in 6/60 (10%) with low-risk carcinoma. After incomplete TEM resection (minimal distance ≤1 mm) LR occurred in 3/8 (38%) patients with low-risk and in 1/5 (20%) patients with high-risk carcinoma. Grading was the only significant risk factor for LR after endoscopic polypectomy followed by TEM (p = 0.002). At all outcomes did not differ between postpolypectomy TEM and primary TEM. CONCLUSIONS: Patients with malignant rectal polyps removed by endoscopic polypectomy have a substantial risk of LR even if TEM of polyp site is cancer free. Risk of LR depends on tumor characteristics. In low-risk carcinoma long-term follow-up is necessary. The high LR rate in patients with high-risk rectal carcinoma restricts the use of TEM alone.


Assuntos
Adenocarcinoma/cirurgia , Pólipos/cirurgia , Proctoscopia/métodos , Neoplasias Retais/cirurgia , Microcirurgia Endoscópica Transanal/métodos , Idoso , Carcinoma/cirurgia , Terapia Combinada , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Estudos Retrospectivos , Fatores de Risco , Tempo , Resultado do Tratamento
14.
Sci Rep ; 6: 31238, 2016 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-27550235

RESUMO

The luminescence and scintillation properties of ZnO single crystals were studied by photoluminescence and X-ray-induced luminescence (XRIL) techniques. XRIL allowed a direct comparison to be made between the near-band emission (NBE) and trap emissions providing insight into the carrier recombination efficiency in the ZnO crystals. It also provided bulk luminescence measurements that were not affected by surface states. The origin of a green emission, the dominant trap emission in ZnO, was then investigated by gamma-induced positron spectroscopy (GIPS) - a unique defect spectroscopy method that enables positron lifetime measurements to be made for a sample without contributions from positron annihilation in the source materials. The measurements showed a single positron decay curve with a 175 ps lifetime component that was attributed to Zn vacancies passivated by hydrogen. Both oxygen vacancies and hydrogen-decorated Zn vacancies were suggested to contribute to the green emission. By combining scintillation measurements with XRIL, the fast scintillation in ZnO crystals was found to be strongly correlated with the ratio between the defect luminescence and NBE. This study reports the first application of GIPS to semiconductors, and it reveals the great benefits of the XRIL technique for the study of emission and scintillation properties of materials.

15.
J Appl Microbiol ; 121(2): 341-51, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27124660

RESUMO

AIMS: The aims of this study were to characterize the antibacterial activity and the chemotype of Litsea cubeba leaf essential oil (EO) harvested in North Vietnam and to investigate the biological effects induced by the leaf powder on growth, nonspecific immunity and survival of common carp (Cyprinus carpio) challenged with Aeromonas hydrophila. METHODS AND RESULTS: The EO showed the prevalence of linalool (95%, n = 5). It was bactericidal against the majority of tested strains, with minimum inhibitory concentrations ranging from 0·72 to 2·89 mg ml(-1) (Aer. hydrophila, Edwarsiella tarda, Vibrio furnissii, Vibrio parahaemolyticus, Streptococcus garvieae, Escherichia coli, Salmonella Typhimurium). The fish was fed with 0 (control), 2, 4 and 8% leaf powder supplementation diets for 21 days. Nonspecific immunity parameters (lysozyme, haemolytic and bactericidal activities of plasma) were assessed 21 days after feeding period and before the experimental infection. Weight gain, specific growth rate and feed conversion ratio were improved by supplementation of L. cubeba in a dose-related manner, and a significant difference appeared at the highest dose (8%) when compared to the control. The increase in plasma lysozyme was significant for all the treated groups. Haemolysis activity was higher for the groups fed with 4 and 8% plant powder. Antibacterial activity increased significantly for the 8% dose only. CONCLUSIONS: Litsea cubeba leaf powder increased nonspecific immunity of carps in dose-related manner. After infection with Aer. hydrophila, survivals of fish fed with 4 and 8% L. cubeba doses were significantly higher than those fed with 2% dose and the control. SIGNIFICANCE AND IMPACT OF THE STUDY: A range of 4-8% L. cubeba leaf powder supplementation diet (from specific linalool-rich chemotype) can be used in aquaculture to reduce antibiotic burden and impacts of diseases caused by Aer. hydrophila.


Assuntos
Aeromonas hydrophila/fisiologia , Antibacterianos/administração & dosagem , Carpas , Doenças dos Peixes/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/veterinária , Litsea/química , Óleos Voláteis/administração & dosagem , Aeromonas hydrophila/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Aquicultura/métodos , Suplementos Nutricionais , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Imunidade Inata , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia
16.
J Nat Prod ; 78(6): 1397-405, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26068600

RESUMO

Five new steroid glycosides, luzonicosides B-E (2-5), belonging to a rare structure group of marine glycosides, containing carbohydrate moieties incorporated into a macrocycle, and a related open carbohydrate chain steroid glycoside, luzonicoside F (6), were isolated from the starfish Echinaster luzonicus along with the previously known cyclic steroid glycoside luzonicoside A (1). The structures of compounds 2-6 were established by extensive NMR and ESIMS techniques as well as chemical transformations. Luzonicoside A (1) at concentrations of 0.01-0.1 µM was shown to be potent in lysosomal activity stimulation, intracellular ROS level elevation, and NO synthesis up-regulation in RAW 264.7 murine macrophages. Luzonicoside D (4) was less active in these biotests.


Assuntos
Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/farmacologia , Estrelas-do-Mar/química , Esteroides/isolamento & purificação , Esteroides/farmacologia , Animais , Glicosídeos/química , Fatores Imunológicos/química , Macrófagos/efeitos dos fármacos , Biologia Marinha , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Espécies Reativas de Oxigênio/análise , Esteroides/química
17.
Phys Chem Chem Phys ; 17(12): 8223-30, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25732332

RESUMO

Thermodynamic equilibrium for adsorption means that the chemical potential of gas and adsorbed phase are equal. A precise knowledge of the chemical potential is, however, often lacking, because the activity coefficient of the adsorbate is not known. Adsorption isotherms are therefore commonly fitted to ideal models such as the Langmuir, Sips or Henry models. We propose here a new procedure to find the activity coefficient and the equilibrium constant for adsorption which uses the thermodynamic factor. Instead of fitting the data to a model, we calculate the thermodynamic factor and use this to find first the activity coefficient. We show, using published molecular simulation data, how this procedure gives the thermodynamic equilibrium constant and enthalpies of adsorption for CO2(g) on graphite. We also use published experimental data to find similar thermodynamic properties of CO2(g) and of CH4(g) adsorbed on activated carbon. The procedure gives a higher accuracy in the determination of enthalpies of adsorption than ideal models do.

18.
Phys Chem Chem Phys ; 17(2): 1226-33, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25418118

RESUMO

We study the adsorption of carbon dioxide at a graphite surface using the new Small System Method, and find that for the temperature range between 300 K and 550 K most relevant for CO2 separation; adsorption takes place in two distinct thermodynamic layers defined according to Gibbs. We calculate the chemical potential and the activity coefficient of both layers directly from the simulations. Based on thermodynamic relations, the entropy and enthalpy of the CO2 adsorbed layers are also obtained. Their values indicate that there is a trade-off between entropy and enthalpy when a molecule chooses for one of the two layers. The first layer is a densely packed monolayer of relatively constant excess density with relatively large repulsive interactions and negative enthalpy. The second layer has an excess density varying with the temperature, an activity coefficient, which also indicates repulsion, but to a much smaller degree than in the first layer. Results for activity coefficients, entropies and enthalpies can be used to model transport through and along graphitic membranes for carbon dioxide separation purposes.

19.
Int J Tuberc Lung Dis ; 15(12): 1643-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22118172

RESUMO

SETTING: Two general hospitals in Viet Nam. OBJECTIVE: To assess the risk of tuberculosis (TB) infection associated with hospital employment. DESIGN: During October-December 2009, we performed a cross-sectional study of hospital personnel and, for community comparison groups, staff from nearby schools. We tested for TB infection using the tuberculin skin test; an induration ≥ 10 mm indicated TB infection. RESULTS: Of 956 hospital personnel, 380 (40%) had TB infection compared to 40 (26%) of 155 school personnel. Hospital personnel had twice the odds of TB infection compared with school personnel (OR 2.0, 95%CI 1.3-3.0) after adjustment for age and sex. Compared to hospital administrative staff, the odds of TB infection were similar among clinical staff (OR 1.0, 95%CI 0.6- 1.3), clinical support staff (OR 0.9, 95%CI 0.5-1.6) and auxiliary staff (OR 1.1, 95%CI 0.6-2.0) at the hospitals. No additional infection risk was detected in high-risk departments (OR 1.1, 95%CI 0.6-2.0). CONCLUSIONS: Hospital personnel are at increased risk of TB infection. Among hospital personnel, risk was independent of job or department, suggesting that personnel are commonly at risk and that improvements in infection control are needed throughout hospitals.


Assuntos
Exposição Ocupacional/estatística & dados numéricos , Recursos Humanos em Hospital , Tuberculose/epidemiologia , Adulto , Idoso , Estudos Transversais , Feminino , Hospitais Gerais , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Instituições Acadêmicas , Teste Tuberculínico , Tuberculose/diagnóstico , Vietnã/epidemiologia , Adulto Jovem
20.
Steroids ; 75(12): 897-904, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20493893

RESUMO

Five new steroidal compounds, including an unusual glucoside, along with several known steroids were isolated from the starfish Archaster typicus collected in shallow waters of Quang Ninh province (Vietnam). Three new compounds are 27-nor-cholestane derivatives and the other two are 24,26-dihydroxycholestane derivatives. A biogenesis pathway for the unusual side chain of 27-nor-cholestane derivatives is proposed. Isolated compounds presented moderate toxic effects in the sperm- and 8-blastomere tests on embryonal development of the sea urchin Strongylocentrotusintermedius.


Assuntos
Água do Mar , Estrelas-do-Mar/química , Esteroides/química , Esteroides/isolamento & purificação , Animais , Etanol/química , Fertilização/efeitos dos fármacos , Hidroxilação , Esteroides/toxicidade , Strongylocentrotus/efeitos dos fármacos , Strongylocentrotus/embriologia , Strongylocentrotus/fisiologia , Vietnã
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