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1.
PLoS Genet ; 19(3): e1010678, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36972302

RESUMO

Cross-resistance to insecticides in multiple resistant malaria vectors is hampering resistance management. Understanding its underlying molecular basis is critical to implementation of suitable insecticide-based interventions. Here, we established that the tandemly duplicated cytochrome P450s, CYP6P9a/b are driving carbamate and pyrethroid cross-resistance in Southern African populations of the major malaria vector Anopheles funestus. Transcriptome sequencing revealed that cytochrome P450s are the most over-expressed genes in bendiocarb and permethrin-resistant An. funestus. The CYP6P9a and CYP6P9b genes are overexpressed in resistant An. funestus from Southern Africa (Malawi) versus susceptible An. funestus (Fold change (FC) is 53.4 and 17 respectively), while the CYP6P4a and CYP6P4b genes are overexpressed in resistant An. funestus in Ghana, West Africa, (FC is 41.1 and 17.2 respectively). Other up-regulated genes in resistant An. funestus include several additional cytochrome P450s (e.g. CYP9J5, CYP6P2, CYP6P5), glutathione-S transferases, ATP-binding cassette transporters, digestive enzymes, microRNA and transcription factors (FC<7). Targeted enrichment sequencing strongly linked a known major pyrethroid resistance locus (rp1) to carbamate resistance centering around CYP6P9a/b. In bendiocarb resistant An. funestus, this locus exhibits a reduced nucleotide diversity, significant p-values when comparing allele frequencies, and the most non-synonymous substitutions. Recombinant enzyme metabolism assays showed that both CYP6P9a/b metabolize carbamates. Transgenic expression of CYP6P9a/b in Drosophila melanogaster revealed that flies expressing both genes were significantly more resistant to carbamates than controls. Furthermore, a strong correlation was observed between carbamate resistance and CYP6P9a genotypes with homozygote resistant An. funestus (CYP6P9a and the 6.5kb enhancer structural variant) exhibiting a greater ability to withstand bendiocarb/propoxur exposure than homozygote CYP6P9a_susceptible (e.g Odds ratio = 20.8, P<0.0001 for bendiocarb) and heterozygotes (OR = 9.7, P<0.0001). Double homozygote resistant genotype (RR/RR) were even more able to survive than any other genotype combination showing an additive effect. This study highlights the risk that pyrethroid resistance escalation poses to the efficacy of other classes of insecticides. Available metabolic resistance DNA-based diagnostic assays should be used by control programs to monitor cross-resistance between insecticides before implementing new interventions.


Assuntos
Anopheles , Inseticidas , Malária , Piretrinas , Animais , Inseticidas/farmacologia , Carbamatos/metabolismo , Piretrinas/metabolismo , Anopheles/genética , Drosophila melanogaster , Resistência a Inseticidas/genética , Mosquitos Vetores/genética , Citocromos/metabolismo , Gana
2.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361877

RESUMO

The development of bacterial resistance to antibiotics is an increasing public health issue that worsens with the formation of biofilms. Quorum sensing (QS) orchestrates the bacterial virulence and controls the formation of biofilm. Targeting bacterial virulence is promising approach to overcome the resistance increment to antibiotics. In a previous detailed in silico study, the anti-QS activities of twenty-two ß-adrenoreceptor blockers were screened supposing atenolol as a promising candidate. The current study aims to evaluate the anti-QS, anti-biofilm and anti-virulence activities of the ß-adrenoreceptor blocker atenolol against Gram-negative bacteria Serratia marcescens, Pseudomonas aeruginosa, and Proteus mirabilis. An in silico study was conducted to evaluate the binding affinity of atenolol to S. marcescens SmaR QS receptor, P. aeruginosa QscR QS receptor, and P. mirabilis MrpH adhesin. The atenolol anti-virulence activity was evaluated against the tested strains in vitro and in vivo. The present finding shows considerable ability of atenolol to compete with QS proteins and significantly downregulated the expression of QS- and virulence-encoding genes. Atenolol showed significant reduction in the tested bacterial biofilm formation, virulence enzyme production, and motility. Furthermore, atenolol significantly diminished the bacterial capacity for killing and protected mice. In conclusion, atenolol has potential anti-QS and anti-virulence activities against S. marcescens, P. aeruginosa, and P. mirabilis and can be used as an adjuvant in treatment of aggressive bacterial infections.


Assuntos
Atenolol , Fatores de Virulência , Camundongos , Animais , Atenolol/farmacologia , Atenolol/metabolismo , Fatores de Virulência/genética , Percepção de Quorum , Biofilmes , Bactérias Gram-Negativas , Pseudomonas aeruginosa , Serratia marcescens/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Proteus mirabilis/metabolismo , Proteínas de Bactérias/metabolismo
3.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-903311

RESUMO

Objective@#The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. @*Materials and Methods@#Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. @*Results@#The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. @*Conclusions@#Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

4.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-895607

RESUMO

Objective@#The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. @*Materials and Methods@#Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. @*Results@#The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. @*Conclusions@#Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

5.
Egypt Heart J ; 71(1): 33, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31865489

RESUMO

BACKGROUND: Cardiac magnetic resonance (CMR) is an extremely accurate and useful modality that can give much data about myocardial damage after acute myocardial infarction and consequently can give a good idea about long-term prognosis. Unfortunately, this modality is still underused in Egypt. We tried to assess the prognostic significance of different parameters derived from CMR in Egyptian patients presenting with ST-elevation myocardial infarction (STEMI) treated by primary percutaneous intervention (PPCI). Twenty-five patients who presented with acute STEMI and were successfully reperfused by PPCI within 12 h from symptoms onset were included. CMR was performed 2-4 days after PPCI. Six months of long-term follow-up for major adverse cardiovascular events (re-infarction, new-onset heart failure and cardiac death) was done. CMR-derived parameters (edema volume, area at risk, infarction volume, infarction percentage, microvascular obstruction volume, microvascular obstruction percentage, myocardial salvage and myocardial salvage index) were analyzed in relation to incidence of major adverse cardiovascular events (MACE). RESULTS: Seven patients suffered from MACE. Univariate logistic regression analysis showed a significant correlation between edema volume (P = 0.04), area at risk (P = 0.05), infarction percentage (P = 0.05) and the occurrence of MACE. Multivariate logistic regression analysis showed that infarction percentage (P = 0.05) is the best parameter that can predict MACE. CONCLUSION: Infarction percentage is potentially the most important prognosticator derived from CMR in Egyptian patients with acute STEMI successfully reperfused by PPCI.

6.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-741318

RESUMO

PURPOSE: To evaluate the efficacy of switching to aflibercept in diabetic macular edema (DME) with suboptimal response to previous anti-vascular endothelial growth factor (anti-VEGF) injections. METHODS: A prospective interventional case series study recruited patients from a single center diagnosed with DME with suboptimal response to anti-VEGF injections. Three consecutive monthly injections of aflibercept were performed. The primary outcome measure was mean change in visual acuity after switching to aflibercept. RESULTS: Forty-two patients (42 eyes) were included. Baseline logarithm of the minimum angle of resolution (logMAR) visual acuity was 0.87 ± 0.23 and improved significantly to 0.62 ± 0.29, 0.56 ± 0.34, and 0.46 ± 0.35 at 1, 2, and 3 months, respectively, after the first injection. Mean baseline retinal thickness was 451.57 ± 107.09 µm and decreased significantly at 1, 2, and 3 months after switching to aflibercept (346.52 ± 79.03, 328.24 ± 81.98, and 313.71 ± 85.79 µm, respectively). Both visual improvement and mean change in retinal thickness were significant in patients with pre-aflibercept best-corrected visual acuity less than 1.0 logMAR but were not significant in patients with best-corrected visual acuity more than 1.0 logMAR. CONCLUSIONS: Switching to aflibercept in DME patients with an unsatisfactory response to previous anti-VEGF injections provided acceptable short-term visual and retinal architectural improvement.


Assuntos
Humanos , Retinopatia Diabética , Fatores de Crescimento Endotelial , Edema Macular , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Retinaldeído , Acuidade Visual
7.
Natural Product Sciences ; : 272-283, 2018.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-741630

RESUMO

The root-knot nematode, Meloidogyne incognita caused a serious damage to many plants. The phenolic components of the leaves of Schinus terebinthifolius were investigated as potential nematicidal agents for M. incognita. Nine compounds were isolated and characterized as viz., 1,2,3,4,6-pentagalloyl glucose (1), kaempferol-3-O-α-L-rhamnoside (Afzelin) (2), quercetin-3-O-α-L-rhamnoside (Quercetrin) (3), myricetin (4), myricetin-3-O-α-L-rhamnoside (Myricetrin) (5), methylgallate (6), protocatechuic acid (7), quercetin (8), and gallic acid (9) using nuclear magnetic resonance (NMR) spectroscopy. Compound 1 showed pronounced nematicidal activity compared to Oxamyl as a positive control. It showed the lowest eggs-hatchability (34%) and the highest mortality in nematode population (21% after 72 hours of treatment) at a concentration of 200 µg/mL. It exhibited the best suppressed total nematode population, root galling and number of eggmasses in infected tomato plants. The total carbohydrates and proteins were also significantly induced by 1 with reduction in total phenolics and increase in defense-related proteins. Thus, compound 1 could be a promising, more safe and effective natural nematicidal agent for the control of root-knot nematodes.


Assuntos
Anacardiaceae , Carboidratos , Ácido Gálico , Glucose , Solanum lycopersicum , Espectroscopia de Ressonância Magnética , Mortalidade , Fenol , Quercetina , Análise Espectral , Tylenchoidea
8.
Pharmazie ; 72(3): 143-151, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442049

RESUMO

Self-nanoemulsifying drug delivery systems (SNEDDS) offer an efficient choice to improve the poor dissolution and erratic bioavailability of poorly-water soluble drugs. However, liquid SNEDDS experience some manufacturing and stability limitations. To overcome these limitations, the current study aims to investigate and optimize the solidification of cinnarizine (CN) liquid SNEDDS onto pellets by fluid bed coating. The study involved optimization of process and formulation variables. The coated self-nanoemulsifying pellets (SNEP) were characterized, their droplet size and dissolution profiles were compared to the corresponding liquid SNEDDS. Higher spray/microclimate air pressure led to minimal agglomeration and minimal spray drying. However, slight increase in inlet air volume above 35 m3/h led to extensive spray drying. The optimized coating formula included oleic acid/Imwitor308/Cremophor El (25/25/50) as liquid SNEDDS, HPMC E3 as coating polymer and Plasacryl™T20 as anti-tacking agent. The optimum concentration of coating solution was 15% and optimum SNEDDS proportion in the coating layer was 40%. The droplet size of reconstituted SNEP was significantly (p < 0.05) higher than liquid SNEDDS, yet the SNEP aqueous dispersion was still within the nano-metric scale. Pure CN showed sharp precipitation upon shifting the media from pH 1.2 to 6.8. In contrast, Both SNEP and liquid SNEDDS maintained >85% CN in solution, even at pH 6.8. Therefore, CN-SNEP seems to be an excellent dosage form that maintains the solubilization benefits of liquid SNEDDS, overcomes their limitations along with the additional benefits of solid dosage form.


Assuntos
Química Farmacêutica/métodos , Cinarizina/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas , Cinarizina/química , Composição de Medicamentos/métodos , Emulsões , Excipientes/química , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Antagonistas dos Receptores Histamínicos H1/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Polímeros/química , Solubilidade
9.
Electron. j. biotechnol ; 18(3): 175-180, May 2015. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-750644

RESUMO

Background Enterococcus faecalis is considered to be one of most prevalent species in the oral cavity, particularly in endodontic infections. The aim of the present study was to investigate the prevalence of E. faecalis in dental root canals, clonal diversity by restriction fragment length polymorphism (RFLP) and randomly amplified polymorphic DNA (RAPD-PCR) analysis, and the antibiotic susceptibility of E. faecalis isolates. Results Among the bacterial strains isolated from dental root canal specimens (n = 82), E. faecalis was determined to have the highest prevalence followed by Streptococcus viridians, Leuconostoc mesenteroides, Staphylococcus aureus, Streptococcus mitis, and Pediococcus pentosaceus. Cluster analysis of RAPD-PCR and RFLP patterns of the E. faecalis isolates discriminated five and six different genotypes, respectively. Among the tested strains, 43%, 52% and 5% were susceptible, intermediate resistant, and resistant to erythromycin, respectively. In addition, one strain (E-12) was intermediate resistant to linezolid, and one isolate (E-16) was resistant to tetracycline. Interestingly, many of the intermediate resistant/resistant strains were grouped in clusters 5 and 6, according RAPD and to RFLP, respectively. Conclusions E. faecalis demonstrated the highest prevalence in the tested dental root canal specimens collected from Saudi patients and were grouped into five to six different genotypes. Different levels of antimicrobial susceptibility were observed in the tested E. faecalis strains, which clearly indicated that although bacterial strains may be similar, point mutations can result in extreme susceptibility or resistance to various antibiotics. This phenomenon is a cause for concern for clinicians in the treatment of dental infections caused by E. faecalis.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Infecções Bacterianas/microbiologia , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/genética , Farmacorresistência Bacteriana , Doenças da Polpa Dentária/microbiologia , Variação Genética , Polimorfismo de Fragmento de Restrição , Testes de Sensibilidade Microbiana , Técnica de Amplificação ao Acaso de DNA Polimórfico , Genótipo
10.
ANZ J Surg ; 81(4): 257-60, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21418469

RESUMO

BACKGROUND: Management of distal malignant large bowel obstruction (LBO) remains challenging. Acute surgical intervention is often associated with poorer clinical outcome compared to an elective procedure. Self-expandable metallic stents (SEMS) as a bridge to surgery (BTS) or palliation remain controversial and are not yet widely available. METHODS: From 1998 to 2008, a retrospective analysis of the patients presenting with an acute malignant LBO to The Tweed Public and John Flynn Private Hospitals was performed. RESULTS: Fifty-six admissions with malignant distal colonic obstruction were reviewed. On an intention to treat, patients underwent either stent 30 or surgery 26. American Association of Anaesthetists (ASA) scores, obesity rates and palliative procedures were all higher in the stent group. Inpatient deaths numbered four (two stent group, two surgery group). The technical success of inserted stents was 29/30, while clinical success was 27/30. Complications both medical, surgical and intensive care unit admissions were more common in the surgical group. Length of stay was 8.5 days for stent and 17.7 days for surgery. Of the 25 successful stent survivors, 14 were palliative and 11 were BTS. CONCLUSIONS: SEMS are effective in treatment of LBO either as palliation or BTS. They are associated with an overall better outcome and improved quality of life of patients. Surgery is indicated where SEMS are unavailable or have failed.


Assuntos
Colectomia/métodos , Colo/cirurgia , Neoplasias Colorretais/complicações , Obstrução Intestinal/cirurgia , Stents , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/cirurgia , Feminino , Seguimentos , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/psicologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento
11.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-625626

RESUMO

The cases of nine patients with unicameral bone cysts were reviewed from two orthopaedic centres. In one hospital, five patients received serial steroid injections, and at the other hospital four patients were treated conservatively following fractures. In the steroid injection group, three cases were in the proximal femur and two in the proximal humerus. The five steroid injection patients showed radiological evidence of cyst healing within six months of treatment. Subsequently four of the patients showed a satisfactory radiological outcome after a year and complete resolution after 2 years. In the conservative group, all four cases were in the proximal humerus. Persistent cystic lesions were observed in all four patients and two was complicated by another fracture within six months.

12.
Ann Thorac Cardiovasc Surg ; 14(5): 325-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18989251

RESUMO

Most parathyroid glands in hyperparathyroidism can be resected through a cervical approach. In approximately 2% of cases, the ectopic gland is in the mediastinum in a location that requires a thoracic approach. Advancement in video-assisted thoracoscopic surgical (VATS) techniques has decreased the need for sternotomy to successfully remove these ectopic glands. We describe a case involving a 29-year-old woman with hyperparathyroidism resulting from an ectopic mediastinal parathyroid adenoma that caused neonatal hypocalcemia, which was removed through VATS.


Assuntos
Adenoma/cirurgia , Coristoma/cirurgia , Hipocalcemia/etiologia , Doenças do Recém-Nascido/etiologia , Neoplasias do Mediastino/cirurgia , Glândulas Paratireoides , Neoplasias das Paratireoides/cirurgia , Complicações Neoplásicas na Gravidez/cirurgia , Cirurgia Torácica Vídeoassistida , Adenoma/complicações , Adenoma/patologia , Adulto , Coristoma/patologia , Feminino , Humanos , Hiperparatireoidismo Primário/etiologia , Hiperparatireoidismo Primário/cirurgia , Hipocalcemia/terapia , Recém-Nascido , Doenças do Recém-Nascido/terapia , Imageamento por Ressonância Magnética , Neoplasias do Mediastino/complicações , Neoplasias do Mediastino/patologia , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/patologia , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
13.
J Pediatr Surg ; 41(7): 1230-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16818054

RESUMO

BACKGROUND: Hydatid cyst still remains an important health problem in our country as in many Mediterranean countries. The disease may affect children, and its treatment may be challenging in this age group. Surgery is the primary way of treatment. In the current study, the features unique to childhood pulmonary hydatid disease are emphasized. METHODS: Between 1992 and 2003, 301 patients were operated on because of pulmonary hydatid cyst in our hospital; 44 of them were 14 years or younger. They were categorized as pediatric patients. We retrospectively evaluated the clinical data of the patients. RESULTS: The mean age of the patients was 10.6 +/- 3.7 years (5-14 years) in children and 32.2 +/- 14 years (16-75 years) in adults. The rate of intact cyst was 71% in children and 57% in adults (P = .07). The mean diameter of the cyst was 8.5 +/- 3.1 cm (3-15 cm) and 6.6 +/- 3 cm (2-16 cm) in children and adults, respectively (P < .001). The rate of parenchyme-saving procedures was 84.1% in children, whereas 94.9% in adults. Lobectomy was performed in 16% of children, whereas it was performed in 1.5% of adults (P < .001). Morbidity rates were 13.6% in children and 11.6% in adults. No children but 1 adult died. Long-term follow-up revealed the recurrence rates as 4.5% in children and 4.3% in adults. CONCLUSIONS: Surgery, the primary method of treatment of hydatid cyst, is safe. Parenchyma-saving procedures such as cystotomy and capitonnage should be performed as much as possible. Nevertheless, hydatid cyst can reach relatively larger dimensions in children than in adults, which causes parenchyme destruction eventually leading to lung resection.


Assuntos
Equinococose Pulmonar/cirurgia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Pulmonares , Estudos Retrospectivos
14.
Tropical Biomedicine ; : 148-54, 2006.
Artigo em Ml | WPRIM (Pacífico Ocidental) | ID: wpr-629806

RESUMO

Childhood obesity is an established problem in many countries and emerging in others. Epidemiological data on obesity in children is essential in order to plan public health policy and services. A study was conducted to determine the prevalence of obesity in schoolchildren in the fifth grade of elementary school (10-12 years old) in the district of Kuala Selangor. Ten schools of which five are in urban and five in rural areas were selected consisting of 699 eleven year old schoolchildren from the three major ethnic groups. Using international cut-off points for obesity, we report an overall prevalence of obesity of 7.2%. Prevalence of obesity in urban children is 7.2% whereas in rural children it is 7.0 %. Analysed by gender, there were 8.9% obese boys and 5.3% obese girls. Among the 3 major ethnic groups, the Malays had the highest prevalence of obesity at 9.3% followed by the Chinese with 6.6% while among Indians 3.0%. The data obtained from this study suggests that obesity in Kuala Selangor children is a cause for concern in urban and rural areas.


Assuntos
Criança , Obesidade , Zona Rural
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