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1.
J Fr Ophtalmol ; 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37088625
2.
Materials (Basel) ; 14(21)2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34772159

RESUMEN

The need to promote sustainable civil infrastructure is one of the most important concerns in the construction industry. Geopolymer composites are one of the promising eco-friendly materials for the development of low carbon concrete. The main objective of this experimental investigation is to study the effect of hybrid fibres on the shear strength of flexural members made with ternary blend geopolymer concrete (TGPC). A total number of 27 reinforced concrete beams of size 100 mm × 150 mm × 1200 mm were cast and tested for shear. M55 grade of concrete was considered in this study. Crimped steel fibres and polypropylene fibres with an aspect ratio of 66 and 300, respectively, were used in this work. The main variables considered in this investigation involve two volume proportions of steel fibres, viz., 0.5% and 1% as well as four volume proportions of polypropylene fibres viz., 0.1%, 0.15%, 0.2% and 0.25%. The hybrid fibre-reinforced ternary blend geopolymer concrete (HTGPC) beams were compared with TGPC beams without fibres. From the test results, it was clear that incorporating hybrid fibres improved the shear strength and changed the type of failure of the beam from shear to flexure. Moreover, a method to predict the ultimate shear strength of HTGPC was proposed, and the estimated values were found to be the same as the test results.

3.
Tropical Biomedicine ; : 1105-1116, 2020.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-862628

RESUMEN

@# Malaria is a life-threatening disease caused by the Plasmodium sp. parasite. Infection results in heightened pro-inflammatory response which contributes to the pathophysiology of the disease. To mitigate the overwhelming cytokine response, host-directed therapy is a plausible approach. Glycogen synthase kinase-3β (GSK3β), a serine/threonine kinase plays a pivotal role in the regulation of inflammatory response during pathogenic infections. The present study was conducted to investigate the chemo-suppressive and cytokine-modulating effects of insulin administration in malaria-infected mice and the involvement of GSK3β. Intraperitoneal administrations of 0.3 and 0.5 U/kg body weight insulin each for four consecutive days into Plasmodium berghei NK65 (PbN)-infected mice resulted in chemo-suppression exceeding 60% and improved median survival time of infected mice (20.5 days and 19 days respectively compared to 15.5 days for non-treated control). Western analysis revealed that pGSK3β (Ser9) intensity in brain samples from insulin-treated (0.3 and 0.5 U/kg body weight) infected mice each were 0.6 and 2.2 times respectively than that in control. In liver samples, pGSK3β (Ser9) intensity from insulin-treated infected mice were significantly higher (4.8 and 16.1 fold for 0.3 and 0.5 U/kg bw respectively) than that in control. Insulin administration decreased both brain and liver pNF-κB p65 (Ser536) intensities (to 0.8 and 0.6 times for 0.3 U/kg bw insulin; and to 0.2 and 0.1 times for 0.5 U/kg bw insulin respectively compared to control). Insulin treatment (0.5 U/kg bw) also significantly decreased the serum levels of pro-inflammatory cytokines (TNF-α (3.3 times) and IFN-γ (4.9 times)) whilst significantly increasing the levels of anti-inflammatory cytokines (IL-4 (4.9 fold) and IL-10 (2.1 fold)) in PbN-infected mice. Results from this study demonstrated that the cytokinemodulating effects of insulin at least in part involve inhibition of GSK3β and consequent inhibition of the activation of NF-κB p65 suggesting insulin as a potential adjunctive therapeutic for malaria.

4.
Tropical Biomedicine ; : 303-317, 2020.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-823185

RESUMEN

@#Burkholderia pseudomallei is the etiologic agent of melioidosis, a major cause of community-acquired pneumonia and sepsis in the endemic areas. The overall mortality of patients with severe melioidosis remains high due to severe sepsis attributed to overwhelming inflammatory cytokine response in spite of recommended antibiotic therapy. It is crucial that therapeutic approaches beyond just effective antibiotic treatment such as adjunct therapy be considered to mitigate the dysregulated inflammatory signaling and augment host defenses. In an acute B. pseudomallei infection model, we have previously demonstrated that treatment with anti-malarial drug, chloroquine, modulated inflammatory cytokine levels and increased animal survivability via Akt-mediated inhibition of glycogen synthase kinase-3β (GSK3β). GSK3β is a downstream effector molecule within the phosphatidylinositol 3-kinase (PI3K)/ Akt axis which plays a pivotal role in regulating the production of pro- and anti-inflammatory cytokines. Here we evaluate the effect of chloroquine treatment in combination with a subtherapeutic dose of the antibiotic doxycycline on animal survivability, cytokine levels and phosphorylation states of GSK3β (Ser9) in a murine model of acute melioidosis infection to investigate whether chloroquine could be used as an adjunct therapy along with doxycycline for the treatment of melioidosis. Our findings revealed that 50 mg/kg b.w. chloroquine treatment together with a dose of 20 mg/kg b.w. doxycycline improved survivability (100%) of mice infected with 3 X LD50 of B. pseudomallei and significantly (P<0.05) lowered the bacterial loads in spleen, liver and blood compared to controls. B. pseudomallei-infected mice subjected to adjunct treatment with chloroquine and doxycycline significantly (P<0.05) reduced serum levels of pro-inflammatory cytokines (TNF-α, IFN-γ and IL-6) but increased levels of antiinflammatory cytokines (IL-4 and IL-10). Western blot analysis demonstrated that the intensities of pGSK3β (Ser9) in liver samples from mice treated with chloroquine and doxycycline combination were significantly (P<0.05) higher suggesting that the adjunct treatment resulted in significant inhibition of GSK3β. Taken together the bacteriostatic action of doxycycline coupled with the cytokine-modulating effect of chloroquine gave full protection to B. pseudomallei-infected mice and involved inhibition of GSK3β. Findings from the present study using B. pseudomallei-infected BALB/c mice suggest that chloroquine is a plausible candidate for repurposing as adjunct therapy to treat acute B. pseudomallei infection.

5.
Trop Biomed ; 37(4): 1105-1116, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33612762

RESUMEN

Malaria is a life-threatening disease caused by the Plasmodium sp. parasite. Infection results in heightened pro-inflammatory response which contributes to the pathophysiology of the disease. To mitigate the overwhelming cytokine response, host-directed therapy is a plausible approach. Glycogen synthase kinase-3ß (GSK3ß), a serine/threonine kinase plays a pivotal role in the regulation of inflammatory response during pathogenic infections. The present study was conducted to investigate the chemo-suppressive and cytokine-modulating effects of insulin administration in malaria-infected mice and the involvement of GSK3ß. Intraperitoneal administrations of 0.3 and 0.5 U/kg body weight insulin each for four consecutive days into Plasmodium berghei NK65 (PbN)-infected mice resulted in chemo-suppression exceeding 60% and improved median survival time of infected mice (20.5 days and 19 days respectively compared to 15.5 days for non-treated control). Western analysis revealed that pGSK3ß (Ser9) intensity in brain samples from insulin-treated (0.3 and 0.5 U/kg body weight) infected mice each were 0.6 and 2.2 times respectively than that in control. In liver samples, pGSK3ß (Ser9) intensity from insulin-treated infected mice were significantly higher (4.8 and 16.1 fold for 0.3 and 0.5 U/kg bw respectively) than that in control. Insulin administration decreased both brain and liver pNF-κB p65 (Ser536) intensities (to 0.8 and 0.6 times for 0.3 U/kg bw insulin; and to 0.2 and 0.1 times for 0.5 U/kg bw insulin respectively compared to control). Insulin treatment (0.5 U/kg bw) also significantly decreased the serum levels of pro-inflammatory cytokines (TNF-α (3.3 times) and IFN-γ (4.9 times)) whilst significantly increasing the levels of anti-inflammatory cytokines (IL-4 (4.9 fold) and IL-10 (2.1 fold)) in PbN-infected mice. Results from this study demonstrated that the cytokinemodulating effects of insulin at least in part involve inhibition of GSK3ß and consequent inhibition of the activation of NF-κB p65 suggesting insulin as a potential adjunctive therapeutic for malaria.


Asunto(s)
Citocinas/sangre , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Insulina/farmacología , Malaria/tratamiento farmacológico , Animales , Encéfalo , Modelos Animales de Enfermedad , Hígado , Malaria/inmunología , Masculino , Ratones , Ratones Endogámicos ICR , Plasmodium berghei , Proteínas Proto-Oncogénicas c-akt , Factor de Transcripción ReIA
6.
Trop Biomed ; 37(2): 303-317, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33612800

RESUMEN

Burkholderia pseudomallei is the etiologic agent of melioidosis, a major cause of community-acquired pneumonia and sepsis in the endemic areas. The overall mortality of patients with severe melioidosis remains high due to severe sepsis attributed to overwhelming inflammatory cytokine response in spite of recommended antibiotic therapy. It is crucial that therapeutic approaches beyond just effective antibiotic treatment such as adjunct therapy be considered to mitigate the dysregulated inflammatory signaling and augment host defenses. In an acute B. pseudomallei infection model, we have previously demonstrated that treatment with anti-malarial drug, chloroquine, modulated inflammatory cytokine levels and increased animal survivability via Akt-mediated inhibition of glycogen synthase kinase-3ß (GSK3ß). GSK3ß is a downstream effector molecule within the phosphatidylinositol 3-kinase (PI3K)/ Akt axis which plays a pivotal role in regulating the production of pro- and anti-inflammatory cytokines. Here we evaluate the effect of chloroquine treatment in combination with a subtherapeutic dose of the antibiotic doxycycline on animal survivability, cytokine levels and phosphorylation states of GSK3ß (Ser9) in a murine model of acute melioidosis infection to investigate whether chloroquine could be used as an adjunct therapy along with doxycycline for the treatment of melioidosis. Our findings revealed that 50 mg/kg b.w. chloroquine treatment together with a dose of 20 mg/kg b.w. doxycycline improved survivability (100%) of mice infected with 3 X LD50 of B. pseudomallei and significantly (P<0.05) lowered the bacterial loads in spleen, liver and blood compared to controls. B. pseudomallei-infected mice subjected to adjunct treatment with chloroquine and doxycycline significantly (P<0.05) reduced serum levels of pro-inflammatory cytokines (TNF-α, IFN-γ and IL-6) but increased levels of antiinflammatory cytokines (IL-4 and IL-10). Western blot analysis demonstrated that the intensities of pGSK3ß (Ser9) in liver samples from mice treated with chloroquine and doxycycline combination were significantly (P<0.05) higher suggesting that the adjunct treatment resulted in significant inhibition of GSK3ß. Taken together the bacteriostatic action of doxycycline coupled with the cytokine-modulating effect of chloroquine gave full protection to B. pseudomallei-infected mice and involved inhibition of GSK3ß. Findings from the present study using B. pseudomallei-infected BALB/c mice suggest that chloroquine is a plausible candidate for repurposing as adjunct therapy to treat acute B. pseudomallei infection.


Asunto(s)
Cloroquina/uso terapéutico , Reposicionamiento de Medicamentos , Melioidosis/tratamiento farmacológico , Animales , Carga Bacteriana , Burkholderia pseudomallei , Citocinas , Doxiciclina/uso terapéutico , Masculino , Ratones , Ratones Endogámicos BALB C
7.
Trop Biomed ; 35(3): 709-723, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33601758

RESUMEN

Melioidosis is a common cause of fatal community-acquired septicaemia and pneumonia in endemic regions even with appropriate antibiotic treatments. The involvement of inflammatory cytokines in the manifestation of melioidosis is well-documented. Antibacterial and anti-inflammatory therapies may prove more efficacious against melioidosis rather than just anti-bacterial therapy alone. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway has a central role in regulating the host inflammatory response; and glycogen synthase kinase-3ß (GSK3ß), a downstream effector molecule within this axis, plays a pivotal role in regulating the production of pro- and anti-inflammatory cytokines. The anti-malarial drug, chloroquine is a novel activator of Akt, and can elicit inhibition of GSK3ß via PI3K/Akt signalling. LiCl, a GSK3 inhibitor is reported to increase survivability and modulate cytokine production in B. pseudomallei-infected mice. Here we determined the effects of chloroquine administration on animal survivability, cytokine levels and phosphorylation states of GSK3ß (Ser9), Akt (Ser473) and NF-κB p65 (Ser536) in a murine model of acute melioidosis infection. Administration of 50 mg/kg b w chloroquine improved survivability (mean 67.0 ± 6.3%) of mice infected with 3 X LD50 B. pseudomallei compared to controls. Bacterial loads in spleen, liver, lung and blood of infected mice administered with chloroquine were significantly lower than controls. Western blot analysis revealed that the intensities of pAkt (Ser473) and pGSK3ß (Ser9) in liver samples of mice administered with chloroquine were significantly (Pandlt;0.05) higher (2.3- and 4.4-fold respectively) compared to controls. On the other hand, chloroquine treatment signicantly decreased (Pandlt;0.05) phosphorylation of NF-κB p65 (Ser536) by 0.7-fold compared to control. Chloroquine administration also resulted in significantly reduced levels of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1ß and IL-18) but increased levels of antiinflammatory cytokines (IL-4 and IL-10) in sera and liver of B. pseudomallei-infected mice. Findings from this study demonstrate that the increased survivability of B. pseudomalleiinfected mice after chloroquine administration is at least in part due to its cytokine-modulating effects elicited via Akt-mediated inhibition of GSK3ß that resulted in inhibition of NF-κB activation. This study represents laboratory evidence of the use of chloroquine for cytokine modulation and a plausible effective adjunctive therapeutic for B. pseudomallei infection.

8.
Tropical Biomedicine ; : 709-723, 2018.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-750803

RESUMEN

@#Melioidosis is a common cause of fatal community-acquired septicaemia and pneumonia in endemic regions even with appropriate antibiotic treatments. The involvement of inflammatory cytokines in the manifestation of melioidosis is well-documented. Antibacterial and anti-inflammatory therapies may prove more efficacious against melioidosis rather than just anti-bacterial therapy alone. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway has a central role in regulating the host inflammatory response; and glycogen synthase kinase-3β (GSK3β), a downstream effector molecule within this axis, plays a pivotal role in regulating the production of pro- and anti-inflammatory cytokines. The anti-malarial drug, chloroquine is a novel activator of Akt, and can elicit inhibition of GSK3β via PI3K/Akt signalling. LiCl, a GSK3 inhibitor is reported to increase survivability and modulate cytokine production in B. pseudomallei-infected mice. Here we determined the effects of chloroquine administration on animal survivability, cytokine levels and phosphorylation states of GSK3β (Ser9), Akt (Ser473) and NF-κB p65 (Ser536) in a murine model of acute melioidosis infection. Administration of 50 mg/kg b w chloroquine improved survivability (mean 67.0 ± 6.3%) of mice infected with 3 X LD50 B. pseudomallei compared to controls. Bacterial loads in spleen, liver, lung and blood of infected mice administered with chloroquine were significantly lower than controls. Western blot analysis revealed that the intensities of pAkt (Ser473) and pGSK3β (Ser9) in liver samples of mice administered with chloroquine were significantly (P<0.05) higher (2.3- and 4.4-fold respectively) compared to controls. On the other hand, chloroquine treatment signicantly decreased (P<0.05) phosphorylation of NF-κB p65 (Ser536) by 0.7-fold compared to control. Chloroquine administration also resulted in significantly reduced levels of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β and IL-18) but increased levels of antiinflammatory cytokines (IL-4 and IL-10) in sera and liver of B. pseudomallei-infected mice. Findings from this study demonstrate that the increased survivability of B. pseudomalleiinfected mice after chloroquine administration is at least in part due to its cytokine-modulating effects elicited via Akt-mediated inhibition of GSK3β that resulted in inhibition of NF-κB activation. This study represents laboratory evidence of the use of chloroquine for cytokine modulation and a plausible effective adjunctive therapeutic for B. pseudomallei infection.

9.
Int Angiol ; 36(1): 1-20, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27606807

RESUMEN

The Asian venous thromboembolism (VTE) prophylaxis guidelines were first published in 2012. Since its first edition, the Asian Venous Thrombosis Forum (AVTF) working group have updated the Asian VTE epidemiology and reviewed issues that were not addressed in the previous guidelines. The authors noted that the rising incidence of VTE across Asia may be attributable to aging population, dietary changes, and increasing incidence of obesity and diabetes. The new additions in the guideline include role of thrombophilia in VTE, bleeding risk in Asians, individual risk assessment, updates in the prevention of VTE in medically ill, bariatric surgery, cancer, orthopedic and trauma patients. The influence of primary thrombophilia in perioperative VTE is still unclear. The secondary risk factors, however, are similar between Asians and Caucasians. The group found no evidence of increased risk of bleeding while using pharmacological agents, including the use of novel anti-coagulants. At present, Caprini risk assessment model is widely used for individual risk assessment. Further validation of this model is needed in Asia. In medically ill patients, pharmacological agents are preferred if there is no bleeding risk. Intermittent pneumatic compression device (IPC) is recommended in patients with bleeding risk but we do not recommend using graduated compressive stockings. In bariatric patients, data on VTE is lacking in Asia. We recommend following current international guidelines. A high index of suspicion should be maintained during postbariatric surgery to detect and promptly treat portomesenteric venous thrombosis. Different cancer types have different thrombotic risks and the types of surgery influence to a large extent the overall VTE risk. Cancer patients should receive further risk assessment. In patients with higher thrombotic risk, either due to predisposing risk or concomitant surgery, low molecular weight heparin is indicated. Different countries appear to have different incidence of VTE following trauma and major orthopedic surgery. We recommend mechanical prophylaxis using IPC as the main method and additional pharmacological prophylaxis if the thrombotic risk is high. As for obstetric practice, we propose adherence to the UK Greentop guideline that is widely accepted and utilized across Asia. To improve VTE thromboprophylaxis implementation in the region, we propose that there should be better health education, establishment of hospital-based guidelines and multidisciplinary collaboration.


Asunto(s)
Tromboembolia Venosa/prevención & control , Tromboembolia Venosa/terapia , Anticoagulantes/uso terapéutico , Asia/epidemiología , Femenino , Fibrinolíticos/uso terapéutico , Hemorragia/prevención & control , Humanos , Incidencia , Aparatos de Compresión Neumática Intermitente , Masculino , Complicaciones Posoperatorias/prevención & control , Embarazo , Medición de Riesgo , Factores de Riesgo , Sociedades Médicas , Medias de Compresión
10.
Indian Heart J ; 67(4): 362-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26304570

RESUMEN

Restrictive cardiomyopathy is the least common type of primary cardiomyopathies. Electrocardiographic recording is abnormal in 99% of patients with RCM. Biatrial enlargement, obliquely elevated ST segment with notched or biphasic late peaking T waves are considered characteristic ECG finding. Significant ST depression with T inversion mimicking subendocardial ischemia has also been reported in patients with RCM and is even suggested as a predictor of sudden cardiac death. We noted a similar ECG pattern in a 16 yr girl with Idiopathic restrictive cardiomyopathy. Coronaries were normal, stress perfusion imaging did not show any perfusion defect. This diffuse resting ST depression with T inversion in precordial & inferior leads along with ST elevation in aVR was persistent for more than six months.


Asunto(s)
Cardiomiopatía Restrictiva/diagnóstico , Electrocardiografía , Sistema de Conducción Cardíaco/fisiopatología , Adolescente , Cardiomiopatía Restrictiva/fisiopatología , Angiografía Coronaria , Diagnóstico Diferencial , Ecocardiografía Doppler , Femenino , Humanos , Imagen por Resonancia Cinemagnética , Imagen de Perfusión Miocárdica
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