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1.
Indian J Anaesth ; 68(2): 153-158, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38435651

RESUMO

Background and Aims: Maternal hypotension is a common and dangerous consequence after a subarachnoid block for a caesarean section. Combining pharmacological methods such as norepinephrine infusion, ondansetron and non-pharmacological methods in delayed supine positioning better impacts the maternal haemodynamic profile. The present study assessed the benefits and adverse effects of combining pharmacological and non-pharmacological methods in hypotension prophylaxis. Methods: This randomised controlled trial was conducted at Cairo University Hospital's obstetric theatre from January to October 2020. The study included 85 parturients who were randomised to two groups. Group Sitting was left seated for 2 min after injection, and Group Control was made to lie down in the supine position immediately after the subarachnoid block. Both groups received prophylactic intravenous norepinephrine infusion, in addition to an ondansetron bolus, before surgery. Patients' systolic blood pressure (SBP) from intrathecal injection until delivery of the foetus, was documented. Results: The Sitting group's SBP (122 (14) mmHg) till delivery was statistically higher than the Control group's readings (114 (10) mmHg) (P = 0.004). The Sitting group's intraoperative SBP values were often greater than the Control group values. In addition, the Sitting group had a reduced hypotension incidence and a lower rate of ephedrine use than the other group, but bradycardia incidence was comparable between both groups. Conclusion: In elective caesarean delivery, combining pharmacological and non-pharmacological methods achieve better results regarding maternal hypotension, vasopressor consumption, nausea and vomiting, and foetal outcomes.

2.
Cureus ; 16(2): e53527, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38445137

RESUMO

Objective To assess pain intensity levels during orthodontic therapy of Class II malocclusion patients undergoing skeletally anchored maxillary molar distalization assisted with different micro-osteoperforation (MOP) approaches. Methods Twenty-seven patients (12 males and 18 females) with a mean age of 16.1 ± 0.3 years were randomized into three equal groups (n=9): Group 1 comprised MOPs on buccal surface, Group 2 comprised MOPs on buccal and palatal surface, and Group 3 comprised the control or no-MOP group. The patients underwent maxillary molar distalization using skeletally anchored distal jet appliance assisted with or without MOPs. The MOPs were applied repeatedly on the buccal and buccal and palatal sides, or no MOP (control). Pain intensity was assessed using a 10 cm visual analog scale after each device activation at 24, 48, 72 hours, and at seven days. Data were analyzed using one-way ANOVA and repeated measures ANOVA for non-paired and paired means. Results Both approaches of buccal and buccal and palatal application of MOPs showed statistically significant (p< 0.01) higher levels of pain intensity after the first activation at 24 hours. Nevertheless, pain intensity levels decreased significantly in both MOP groups and between the two activations. Conclusion The repeated application of MOPs on either the buccal side only or on both buccal and palatal sides during maxillary molar distalization did not affect the levels of pain experienced; however, these levels were reported to be higher than that obtained in the control group. Moreover, it is observed that these pain levels tend to gradually reduce to mild levels over the subsequent days.

4.
BMC Vet Res ; 19(1): 23, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717850

RESUMO

An important food-producing sector in Egypt is aquaculture and fisheries; however, several pathogenic microorganisms lead to high mortalities and significant economic losses. The occurrence of Psychrobacter glacincola infection among 180 wild marine fishes collected from the Red sea at Hurghada, Egypt were investigated in the present study. The disease prevalence rate was 6.7%. The recovered isolates were subjected to biochemical and molecular identification. The study also investigated pathogenicity and the antibiogram profile of the recovered isolates. The clinical examination of the infected fish revealed various signs that included lethargy and sluggish movement, hemorrhages and ulcers on the body and the operculum, scale loss, and fin congestion and rot, especially at the tail fin. Furthermore, during postmortem examination, congestion of the liver, spleen, and kidney was observed. Interestingly, 12 isolates were recovered and were homogenous bacteriologically and biochemically. The phylogenetic analysis based on 16S rRNA gene confirmed that MRB62 identified strain was closely related the genus Psychrobacter and identified as P. glacincola and was pathogenic to Rhabdosargus haffara fish, causing 23.3% mortality combined with reporting a series of clinical signs similar to that found in naturally infected fishes. The present study also showed that P. glacincola isolates were sensitive to all antibiotics used for sensitivity testing. Our findings add to the body of knowledge regarding the occurrence of pathogenic P. glacincola infection in Egyptian marine fishes and its potential effects on fish. Future large-scale surveys exploring this bacterium among other freshwater and marine fishes in Egypt would be helpful for the implementation of effective strategies for the prevention and control of this infection are warranted.


Assuntos
Psychrobacter , Animais , Psychrobacter/genética , Egito/epidemiologia , RNA Ribossômico 16S/genética , Filogenia , Oceano Índico , Peixes/genética
5.
J Craniofac Surg ; 34(1): e52-e57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36036490

RESUMO

BACKGROUND: The use of a tissue expander in maxillofacial intraoral tissue reconstruction is a developing approach, which provide adequate tissue coverage and aesthetics. OBJECTIVES: The purpose of this study was to quantitatively compare the use of a soft tissue expander in conjunction with autogenous bone graft with bone graft alone for the repair of the mandible's anterior region. METHODS: The study comprised 24 patients with bone defects in the anterior mandibular region. Patients were divided into 2 groups at random. In group I, expander with bone graft was used, whereas in group II, bone graft was used alone. Volumetric measures of the grafted area was performed using CBCT, and cephalometric evaluations of the anteroposterior and vertical skeletal relationship, as well as the soft tissue profile were recoded. A comparison was made between the 2 groups 6 and 24 months after surgery with P ≤ 0.05 considered significant. RESULTS: The mean difference in grafted bone volume between the 2 groups was 1.95 cm 3 , indicating a significant difference between the 2 groups ( P = 0.05) with superior group I results. The soft tissue profile of group I demonstrated a considerable improvement and stability of the lower lip, the labiomental sulcus, and the thickness of the soft tissue Pogonion compared with group II. CONCLUSION: The use of a tissue expander in conjunction with a bone graft resulted in a better soft tissue profile, making it a favored approach in maxillofacial reconstruction.


Assuntos
Reconstrução Mandibular , Dispositivos para Expansão de Tecidos , Humanos , Transplante Ósseo/métodos , Estética Dentária , Reconstrução Mandibular/métodos
6.
Int J Mol Sci ; 25(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38203194

RESUMO

Cancer was initially attributed to genetic mutations and gene alterations, which resemble genetic diseases caused by various modifications of a specific gene in the genome sequence [...].


Assuntos
RNA não Traduzido , Mutação , RNA não Traduzido/genética
7.
BMC Ophthalmol ; 22(1): 492, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36522705

RESUMO

BACKGROUND: The goal of this work is to assess progression of diabetic macular edema (DME) following intravitreal ranibizumab injection compared to subtenon triamcinolone acetonide injection at cataract operation. METHODS: Retrospective analysis of 73 eyes of 65 participant with DME, with central macular thickness (CMT) ≥ 300 µm. The included eyes were separated into three groups; phacoemulsification with intravitreal Ranibizumab injection group, phacoemulsification with subtenon Triamcinolone acetonide injection group and phacoemulsification only group. Main measures involved best corrected visual acuity (BCVA) one week, one month and three months post-operative. The CMT was compared preoperative and postoperative (one and three months). RESULTS: After 1 month of operation, there was a statistical substantial distinction in the median of CMT between ranibizumab & control group (p < 0.001), between subtenon TA & control group (p < 0.001) and in ranibizumab and subtenon TA group (p = 0.023). After 3 months, the variance between ranibizumab & control group was considerable (p < 0.0001) and the variance between subtenon TA & control group was considerable (p = 0.030). CONCLUSIONS: Combined phacoemulsification with intravitreal injections of ranibizumab or subtenon triamcinolone acetonide may prevent further progression in CMT in individuals with DME following cataract operation.


Assuntos
Catarata , Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Humanos , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Edema Macular/prevenção & controle , Ranibizumab/uso terapêutico , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Injeções Intravítreas , Estudos Retrospectivos , Acuidade Visual , Triancinolona Acetonida/uso terapêutico , Glucocorticoides/uso terapêutico , Catarata/complicações , Resultado do Tratamento
8.
Materials (Basel) ; 15(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500034

RESUMO

Motivated by the loss of tensile strength in 9%Ni steel arc-welded joints performed using commercially available Ni-based austenitic filler metals, the viability of retaining tensile strength using an experimentally produced matching ferritic filler metal was confirmed. Compared to the austenitic Ni-based filler metal (685 MPa), higher tensile strength in gas metal arc (GMA) welded joints was achieved using a ferritic filler metal (749 MPa) due to its microstructure being similar to the base metal (645 MPa). The microstructure of hard martensite resulted in an impact energy of 71 J (-196 °C), which was two times higher than the specified minimum value of ≥34 J. The tensile and impact strength of the welded joint is affected not only by its microstructure, but also by the degree of its mechanical mismatch depending on the type of filler metal. Welds with a harder microstructure and less mechanical mismatch are important for achieving an adequate combination of tensile strength and notched impact strength. This is achievable with the cost-effective ferritic filler metal. A more desirable combination of mechanical properties is guaranteed by applying low preheating temperature (200 °C), which is a more practicable and economical solution compared to the high post-weld heat treatment (PWHT) temperature (580 °C) suggested by other research.

9.
Front Public Health ; 10: 998890, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225781

RESUMO

Background: Mental and psychological health issues are on the rise globally. People with disabilities are at greater risk of poor psychological quality of life especially after covid-19 pandemic. Along with other factors physical activity (PA) may have a significant effect on mental health. This study aims to analyze the difference of PA participation and sitting time among people with and without disabilities and their association with psychological quality of life. Methods: A standard questionnaire was used to collect the data from disabled and non-disabled participants above 15 years of age. Bivariate and multivariate analysis was performed to yield statistical results. Results: Total study sample consisted of 359 participants (67.7% without disability and 32.3% with disability). Participants without disabilities reported a significantly better psychological quality of life (QOL) (Mean score = 68) as compared to the ones with disabilities (Mean score = 61), (p < 0.01). There was significant difference between the sitting time of two groups with longer sitting time among people with disabilities (6.1 h/day) as compared to non-disabled (5.3 h). Optimum level of PA was strongly associated with better psychological quality of life among individuals without disabilities (p = 0.00). Younger age (p = 0.00) and being single (p = 0.01) were significant predictors of poor psychological health among non-disables. Increase in sedentary sitting time was significantly associated with poor psychological quality of life among both groups. Conclusions: Tailored health policies to encourage PA and reduce sitting hours should be formulated to improve psychological health with special focus on individuals with disabilities. Future studies with large sample size are recommended to validate the current results and further explore the difference in association of PA and psychological wellbeing in people with and without disabilities.


Assuntos
COVID-19 , Pessoas com Deficiência , COVID-19/epidemiologia , Pessoas com Deficiência/psicologia , Exercício Físico , Humanos , Pandemias , Qualidade de Vida/psicologia , Arábia Saudita , Postura Sentada , Inquéritos e Questionários
10.
Int Orthod ; 20(3): 100660, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35739004

RESUMO

OBJECTIVE: This retrospective investigation aimed to compare Bolton's ratios among different malocclusion groups of Egyptian adolescent orthodontic patients with original Bolton's standards. MATERIALS AND METHODS: Pre-treatment dental casts of 588 Egyptian subjects, 290 males and 298 females with mean age 16.7±2.2 years, were randomly selected and classified into 220 class I (108 males and 112 females), 230 class II (112 males and 118 females), and 138 class III (68 males and 70 females) groups. Mesiodistal widths from first molar to first molar were measured on 3-dimensionally scanned models via software and ratios were calculated. Two-way analysis of variance compared ratios as a function of skeletal classification and gender. Additionally, percentages of significant discrepancy outside 2 standard deviations (SDs) were calculated. RESULTS: The anterior mean ratio for the total sample were higher (79.4±4.7) and overall mean ratio was lower (90.1±5) than Bolton's standards. The differences between the obtained and standard values were statistically significant (P<0.001). However, there were no significant differences in either anterior ratio (P=0.637) or overall ratio (P=295) regarding gender. Class I cases showed the highest mean anterior ratio of 80±5.7 whereas class II and class III cases had the lowest ratio of 78.5±4.6 and 78.7±3.5, respectively. Concerning overall ratio, class III subjects had the highest ratio of 91.8±2.6 with no substantial distinction from class II cases (90.2±4.7) but was significantly different from class I cases that demonstrated the lowest ratio (89.7±5, P=0.020). High percentages of patients displayed clinically significant tooth size discrepancies (TSD), exceeding either above or below 2SD of Bolton's values, which were more marked in the anterior ratio. These were 25.2% and 7.4% for anterior ratio and 3.4% and 15.4% for overall ratio. CONCLUSIONS: Tooth size ratios of Egyptian orthodontic patients are generally different than the original Bolton's standards. Patients with class I and class III malocclusions had greater anterior and overall ratios than those with class II malocclusions with no considerable gender differences in either ratio.


Assuntos
Má Oclusão , Dente , Adolescente , Egito , Feminino , Humanos , Masculino , Odontometria , Estudos Retrospectivos
11.
Clin Exp Pharmacol Physiol ; 49(7): 710-718, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35527471

RESUMO

Endothelin-1 (ET-1) is implicated in the development of atherosclerosis and mediates glycosaminoglycan (GAG) chain hyperelongation on proteoglycans. Our aim was to identify the ET-1-mediated signalling pathway involving NADPH oxidase (NOX), p38 MAP kinsae and Smad2 linker region phosphorylation (phospho-Smad2L) regulate GAG synthesising enzymes mRNA expression (C4ST-1 and ChSy1) involved in GAG chains hyperelongation in human vascular smooth muscle cells (VSMCs). Signalling intermediates were detected and quantified by Western blotting and the mRNA levels of GAG synthesising enzymes were assessed by quantitative real-time polymerase chain reaction (qRT-PCR). ET-1 treatment of human VSMCs resulted in an increase in phospho-Smad2L level. The TGF-ß receptor antagonist, SB431542 and the mixed ETA and ETB receptor antagonist bosentan, inhibited ET-1-mediated phospho-Smad2L level. In the presence of apocynin and diphenyleneiodonium chloride (DPI) (NOX inhibitors) and SB239063 (p38 inhibitor) ET-1-mediated phospho-Smad2L levels were inhibited. The gene expression levels of GAG synthesising enzymes post-ET-1 treatment were increased compared to untreated controls (p < 0.01). The ET-mediated the mRNA levels of these enzymes were blocked by the bosentan, SB431542, SB239063, DPI, apocynin and antioxidant N-acetyl-L-cysteine (NAC). ET-1-mediated signalling to GAG synthesising enzymes gene expression occurs via transactivation-dependent pathway involving NOX, p38 MAP kinsae and Smad2 linker region phosphorylation.


Assuntos
Endotelina-1 , Glicosaminoglicanos , Bosentana , Endotelina-1/genética , Endotelina-1/metabolismo , Genes gag , Glicosaminoglicanos/metabolismo , Humanos , NADPH Oxidases/metabolismo , Fosforilação , RNA Mensageiro/metabolismo
12.
Food Waterborne Parasitol ; 26: e00144, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35146144

RESUMO

Trichinella spiralis larvae have very special characters that make them able to completely transform the function of the affected muscle cells towards a self-serving environment, offering them nourishment and protection via what is known as "nurse cells". This setting may be affected by drugs that are used for the treatment of co-morbidities and co-infections as calcium channel blockers, which are widely used in clinical practice. In the present study, the effects of verapamil, ivermectin (IVM), and their combined administration on the parasitic burden, immuno-pathology and angiogenesis were investigated during experimental trichinellosis. Estimation of intestinal adult parasitic stages and muscle larvae was done. VEGF gene expression and CD31 immunohistochemical local expression were measured to investigate angiogenesis, in addition to histopathological examination to explore the extent of inflammation. Although verapamil did not have an effect on the adult worm count during the intestinal phase, it induced an anti-inflammatory effect on intestinal pathology. During the muscle phase, it was very effective in reducing the larval count by 93.78%. IVM effectively reduced the worm count by 85.34%, and the muscle larval count by 97.84%, while combined verapamil and IVM administration resulted in a significant reduction in both adult parasites by 69.5% and larval stages by 99%. Both verapamil and IVM and their combination induced a potent decrease in local CD31 protein expression and VEGF gene expression. The important role of calcium and calcium channels during the pathology of trichinellosis, in addition to the pivotal role of calcium on biological processes such as immunity and angiogenesis, make calcium-channel blockers promising candidates for drug repurposing in the management of helminthic infection.

13.
Cell Mol Life Sci ; 79(2): 121, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35122536

RESUMO

Toll-like receptors (TLRs) recognise pathogen­associated molecular patterns, which allow the detection of microbial infection by host cells. Bacterial-derived toxin lipopolysaccharide activates TLR4 and leads to the activation of the Smad2 transcription factor. The phosphorylation of the Smad2 transcription factor is the result of the activation of the transforming growth factor-ß receptor 1 (TGFBR1). Therefore, we sought to investigate LPS via TLR4-mediated Smad2 carboxy terminal phosphorylation dependent on the transactivation of the TGFBR1. The in vitro model used human aortic vascular smooth muscle cells to assess the implications of TLR4 transactivation of the TGFBR1 in vascular pathophysiology. We show that LPS-mediated Smad2 carboxy terminal phosphorylation is inhibited in the presence of TGFBR1 inhibitor, SB431542. Treatment with MyD88 and TRIF pathway antagonists does not affect LPS-mediated phosphorylation of Smad2 carboxy terminal; however, LPS-mediated Smad2 phosphorylation was inhibited in the presence of MMP inhibitor, GM6001, and unaffected in the presence of ROCK inhibitor Y27632 or ROS/NOX inhibitor DPI. LPS via transactivation of the TGFBR1 stimulates PAI-1 mRNA expression. TLRs are first in line to respond to exogenous invading substances and endogenous molecules; our findings characterise a novel signalling pathway in the context of cell biology. Identifying TLR transactivation of the TGFBR1 may provide future insight into the detrimental implications of pathogens in pathophysiology.


Assuntos
Lipopolissacarídeos/farmacologia , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptor 4 Toll-Like/metabolismo , Ativação Transcricional/efeitos dos fármacos , Benzamidas/farmacologia , Linhagem Celular , Dioxóis/farmacologia , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fosforilação , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Proteína Smad2/metabolismo , Regulação para Cima/efeitos dos fármacos
14.
Mol Cell Biochem ; 477(4): 981-988, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34982346

RESUMO

G protein-coupled receptor (GPCR) agonist endothelin-1 (ET-1) through transactivation of the transforming growth factor (TGF) ß receptor (TGFBR1) stimulates glycosaminoglycan (GAG) elongation on proteoglycans. GPCR agonists thrombin and lysophosphatidic acid (LPA) via respective receptors transactivate the TGFBR1 via Rho/ROCK dependent pathways however mechanistic insight for ET-1 transactivation of the TGFBR1 remains unknown. NADPH oxidase (NOX) generates reactive oxygen species (ROS) and is a signalling entity implicated in the pathogenesis of many diseases including atherosclerosis. If implicated in this pathway, NOX/ROS would be a potential therapeutic target. In this study, we investigated the involvement of NOX in ET-1/ET receptor-mediated transactivation of TGFBR1 to stimulate mRNA expression of GAG chain synthesizing enzymes chondroitin 4-O-sulfotransferase 1 (C4ST-1) and chondroitin sulfate synthase 1 (ChSy-1). The invitro model used vascular smooth muscle cells that were treated with pharmacological antagonists in the presence and absence of ET-1 or TGF-ß. Proteins and phosphoproteins isolated from treated cells were quantified by western blotting and quantitative real-time PCR was used to assess mRNA expression of GAG synthesizing enzymes. In the presence of diphenyliodonium (DPI) (NOX inhibitor), ET-1 stimulated phospho-Smad2C levels were inhibited. ET-1 mediated mRNA expression of GAG synthesizing enzymes C4ST-1 and ChSy-1 was also blocked by TGBFR1 antagonists, SB431542, broad spectrum ET receptor antagonist bosentan, DPI and ROS scavenger N-acetyl-L-cysteine. This work shows that NOX and ROS play an important role in ET-1 mediated transactivation of the TGFBR1 and downstream gene targets associated with GAG chain elongation. As ROS is involved in GPCR to protein tyrosine kinase receptor transactivation, the NOX/ROS axis presents as the first common biochemical target in all GPCR to kinase receptor transactivation signalling.


Assuntos
Endotelina-1/metabolismo , Glicosaminoglicanos/metabolismo , NADPH Oxidases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/biossíntese , Ativação Transcricional , Células Cultivadas , Endotelina-1/genética , Humanos , NADPH Oxidases/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/genética
15.
Int Urol Nephrol ; 54(2): 289-298, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34146218

RESUMO

OBJECTIVE: To investigate the efficacy of exercise training on functional capacity and quality of life in chronic kidney disease. DATA SOURCES: SCOPUS, CINAHL, Science Direct, Web of Science, MEDLINE, ProQuest, Physiotherapy Evidence Database (PEDRO), and Google Scholar databases were searched between 2010 and December 2020. METHODS: Randomized controlled trials were included if they involved any types of exercise training (aerobic, resisted and respiratory ex.) conducted with chronic kidney disease patients. Three authors independently screened articles, extracted data, and assessed the methodological quality using PEDro scale, and two authors released any confliction. Modified Sackett Scale was used to determine the level of evidence for each outcome. RESULTS: Out of 130 papers screened, 13 studies with 619 participants met the inclusion criteria. The frequency of the treatment ranged from three to four sessions per week for a period ranging from 8 to 24 weeks. According to the Pedro scale, the quality of studies ranged from good (three studies) to fair (ten studies). All included studies showed positive effects on the measured outcomes (functional capacity and quality of life in chronic kidney disease). CONCLUSION: Exercise programs for chronic kidney disease patients provide beneficial clinical outcomes and optimize functional capacity and quality of life in those patients. Future studies still need to focus on high-quality evidence and studies evaluating the adverse effects of exercise.


Assuntos
Terapia por Exercício , Exercício Físico , Qualidade de Vida , Insuficiência Renal Crônica/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
16.
FEBS J ; 289(9): 2642-2656, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34826189

RESUMO

Transforming growth factor (TGF)-ß signalling commences with the engagement of TGF-ß ligand to cell surface TGF-ß receptors (TGFBR) stimulating Smad2 carboxyl-terminal phosphorylation (phospho-Smad2C) and downstream biological responses. In several cell models, G protein-coupled receptors (GPCRs) transactivate the TGF-ß receptors type-1 (TGFBR1) leading to phospho-Smad2C, however, we have recently published that in keratinocytes thrombin did not transactivate the TGFBR1. The bulk of TGFBRs reside in the cytosol and in response to protein kinase B (Akt phosphorylation) can translocate to the cell surface increasing the cell's responsiveness to TGF-ß. In this study, we investigate the role of Akt in GPCR transactivation of the TGFBR1. We demonstrate that angiotensin II and thrombin do not phosphorylate Smad2C in human vascular smooth muscle cells and in keratinocytes respectively. We used Akt agonist, SC79 to sensitise the cells to Akt and observed that Ang II and thrombin phosphorylate Smad2C via Akt/AS160-dependent pathways. We show that SC79 rapidly translocates TGFBRs to the cell surface thus increasing the cell's response to the GPCR agonist. These findings highlight novel mechanistic insight for the role of Akt in GPCR transactivation of the TGFBR1.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Trombina , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Trombina/metabolismo , Ativação Transcricional , Fator de Crescimento Transformador beta/metabolismo
17.
J Parasit Dis ; 44(4): 694-701, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33184536

RESUMO

Blastocystis sp. is a group of anaerobic protozoa parasitizing the gastrointestinal tract of humans and a broad variety of animals. Evidences of Blastocystis parasites resistance development to antiprotozoal drugs urge the exploration of new therapeutics. Antiprotozoal potential of Salvadora persica, a medicinal plant traditionally used for oral hygiene, was evaluated in vitro against Blastocystis sp. human isolates. Until now, no study has described the effect of S. persica extracts on this parasitic protozoa. Blastocystis sp. positive stool samples collected from patients with gastrointestinal complaints and asymptomatic individuals diagnosed by microscopy were furthermore cultured in vitro and characterized by PCR and multiplex-PCR using sequence-tagged-site primers to determine their subtypes. Out of 21 Blastocystis sp. isolates, five were determined as ST1, 14 as ST3, and two as ST5 subtypes. Antiprotozoal activity of untreated and heat-treated S. persica roots aqueous extracts was evaluated in vitro by serial dilutions on three Blastocystis sp. subtypes; ST1, ST3, and ST5 isolated from symptomatic patients. A significant killing activity was observed with both, untreated and heat-treated aqueous extracts of S. persica at minimal concentration of 2.5 µl/ml compared to parasites' growth controls (P < 0.05). Maximal antiprotozoal effect was reached at a concentration of 20 µl/ml of S. persica aqueous extract. Means of growth inhibition effect obtained with untreated and heat-treated extracts at 40 µl/ml against the three subtypes of Blastocystis sp. were 80% (SD 2.3) and 82% (SD 1.1), respectively. No significant difference was observed in the inhibitory effect of S. persica extracts between the three Blastocystis sp. subtypes. Aqueous extract of S. persica roots contains therefore heat-stable components with significant antiprotozoal activity against Blastocystis sp. subtypes ST1, ST3, and ST5 in vitro. Further investigations are required to determine and characterize the active antiprotozoal components of S. persica roots and their evaluation in vivo.

18.
ACS Pharmacol Transl Sci ; 3(3): 524-534, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32566917

RESUMO

Atherosclerosis begins in the vessel wall with the retention of low density lipoproteins to modified proteoglycans with hyperelongated glycosaminoglycan (GAG) chains. Bacterial infections produce endotoxins such as lipopolysaccharide that exacerbate the outcome of atherosclerosis by generating a heightened state of inflammation. Lipopolysaccharide (LPS) via its toll-like receptor (TLR) is well-known for its role in mediating an inflammatory response in the body. Emerging evidence demonstrates that TLRs are involved in regulating vascular functions. In this study we sought to investigate the role of LPS in proteoglycan modification and GAG chain elongation, and we hypothesize that LPS will signal via Smad2 dependent pathways to regulate GAG chain elongation. The in vitro model used human aortic vascular smooth muscle cells. GAG gene expression was assessed by quantitative real-time polymerase chain reaction. Western blotting was performed using whole-cell protein lysates to assess the signaling pathway. LPS via TLR4 stimulates the expression of GAG synthesizing enzymes to an equal extent to traditional cardiovascular agonists. LPS phosphorylates the Smad2 linker region via TAK-1/MAPK dependent pathways which correlated with genes associated with GAG chain initiation and elongation. The well-characterized role of LPS in inflammation and our data on GAG gene expression demonstrates that GAG chain elongation is the earliest marker of the inflammatory cascade in atherosclerosis development.

19.
Cell Mol Life Sci ; 77(2): 243-251, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31407020

RESUMO

Transforming growth factor (TGF)-ß signalling pathways are intensively investigated because of their diverse association with physiological and pathophysiological states. Smad transcription factors are the key mediators of TGF-ß signalling. Smads can be directly phosphorylated in the carboxy terminal by the TGF-ß receptor or in the linker region via multiple intermediate serine/threonine kinases. Growth factors in addition to hormones and TGF-ß can activate many of the same kinases which can phosphorylate the Smad linker region. Historically, Smad linker region phosphorylation was shown to prevent nuclear translocation of Smads and inhibit TGF-ß signalling pathways; however, it was subsequently shown that Smad linker region phosphorylation can be a driver of gene expression. This review will cover the signalling pathways of Smad linker region phosphorylation that drive the expression of genes involved in pathology and pathophysiology. The role of Smad signalling in cell biology is expanding rapidly beyond its role in TGF-ß signalling and many signalling paradigms need to be re-evaluated in terms of Smad involvement.


Assuntos
Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Expressão Gênica/fisiologia , Humanos
20.
Biochim Biophys Acta Gen Subj ; 1864(1): 129463, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676288

RESUMO

BACKGROUND: Widely used NAPDH oxidase (Nox) inhibitor, apocynin is a prodrug that needs to be converted to its pharmacologically active form by myeloperoxidase. In myeloperoxidase deficient non phagocytic cells such as vascular smooth muscle cells (VSMCs) apocynin stimulates the production of ROS. ROS is generated by the activation of many signalling pathways, thus we have used apocynin as a pharmacological tool to characterise the role of endogenous ROS in activating the transforming growth factor beta receptor (TGFBR1) without the activation of other pathways. METHODS: The in vitro study utilized human VSMCs. Western blotting and quantitative real time PCR were performed to assess signalling pathways and gene expression, respectively. Intracellular ROS levels was measured using fluorescence detection assay. RESULTS: Treatment with apocynin of human VSMCs stimulated ROS production and the phosphorylation of TGFBR1 and subsequent activation of TGFBR1 signalling leading to the formation of phosphorylated Smad2 which consequently upregulates the mRNA expression of glycosaminoglycan synthesizing enzyme. CONCLUSIONS: These findings outline a specific involvement of ROS production in TGFBR1 activation. Furthermore, because apocynin stimulates Nox and ROS production, apocynin must be used with considerable care in vitro as its actions clearly extend beyond the stimulation of Nox enzymes and it has consequences for cellular signalling. GENERAL SIGNIFICANCE: Apocynin can stimulate Nox leading to the production of ROS and the outcome is completely dependent upon the redox properties of the cell.


Assuntos
Acetofenonas/farmacologia , Antioxidantes/farmacologia , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Proteína Smad2/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , NADPH Oxidases/genética , Oxirredução/efeitos dos fármacos , Peroxidase/genética , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
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