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1.
J Nanobiotechnology ; 22(1): 254, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755625

RESUMO

AIM: The antifungal activity was studied on sessile and persister cells (PCs) of Candida tropicalis biofilms of gold nanoparticles (AuNPs) stabilized with cetyltrimethylammonium bromide (CTAB-AuNPs) and those conjugated with cysteine, in combination with Amphotericin B (AmB). MATERIALS/METHODS: The PC model was used and synergistic activity was tested by the checkerboard assay. Biofilms were studied by crystal violet and scanning electron microscopy. RESULTS/CONCLUSIONS: After the combination of both AuNPs and AmB the biofilm biomass was reduced, with significant differences in architecture being observed with a reduced biofilm matrix. In addition, the CTAB-AuNPs-AmB combination significantly reduced PCs. Understanding how these AuNPs aid in the fight against biofilms and the development of new approaches to eradicate PCs has relevance for chronic infection treatment.


Assuntos
Anfotericina B , Antifúngicos , Biofilmes , Candida tropicalis , Sinergismo Farmacológico , Ouro , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Candida tropicalis/efeitos dos fármacos , Ouro/química , Ouro/farmacologia , Biofilmes/efeitos dos fármacos , Anfotericina B/farmacologia , Anfotericina B/química , Nanopartículas Metálicas/química , Antifúngicos/farmacologia , Antifúngicos/química , Cetrimônio/química , Compostos de Cetrimônio/farmacologia , Compostos de Cetrimônio/química
2.
Bull Entomol Res ; 109(1): 111-118, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29784071

RESUMO

Lysinibacillus sphaericus (Bacillales: Planococcaceae) is a spore-forming bacillus used for the biological control of mosquitoes (Diptera: Culicidae) due to its larvicidal activity determined by various toxins and S-layer protein produced either during sporulation or by the vegetative cell. Aedes aegypti and Culex quinquefasciatus are the vectors of arboviruses that cause tropical diseases representing a current public health problem. Both species may coexist in the same larval development sites and are susceptible to the larvicidal activity of L. sphaericus. In this study, we compared the larvicidal effects of L. sphaericus 2362 (WHO Reference strain) and native strains III(3)7 and OT4b.25 against Cx. quinquefasciatus and Ae. aegypti in single-species and mixed-culture bioassays. Findings showed that L. sphaericus spores, vegetative cells and a combination thereof possessed high larvicidal activity against Cx. quinquefasciatus larvae, whereas only the formulation of L. sphaericus vegetative cells was effective against Ae. aegypti larvae. Similar results were obtained for field-collected larvae. We propose that a formulation of vegetative cells of L. sphaericus 2362 or III(3)7 could be a good alternative to chemical insecticides for the in situ control of mixed populations of Ae. aegypti and Cx. quinquefasciatus.


Assuntos
Aedes , Culex , Controle Biológico de Vetores , Planococáceas , Animais , Larva
3.
SAR QSAR Environ Res ; 28(12): 1011-1023, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29135323

RESUMO

This study performed an analysis of the influence of the training and test set rational selection on the quality and predictively of the quantitative structure-activity relationship (QSAR) model. The study was carried out on three different datasets of Influenza Neuraminidase (H1N1) inhibitors. The three datasets were divided into training and test sets using three rational selection methods: based on k-means, Kennard-Stone algorithm and Activity and the results were compared with Random selection. Then, a total of 31,490 mathematical models were developed and those models that presented a determination coefficient higher than: r2train > 0.8, r2loo > 0.7, r2test > 0.5 and minimum standard deviation (SD) and minimum root-mean square error (RMS) were selected. The selected models were validated using the internal leave-one-out method and the predictive capacity was evaluated by the external test set. The results indicate that random selection could lead to erroneous results. In return, a rational selection allows for obtaining more reliable conclusions. The QSAR models with major predictive power were found using the k-means algorithm and selection by activity.


Assuntos
Antivirais/química , Neuraminidase/antagonistas & inibidores , Relação Quantitativa Estrutura-Atividade , Algoritmos , Antivirais/análise , Vírus da Influenza A Subtipo H1N1 , Modelos Moleculares
4.
Acta Ortop Mex ; 31(1): 48-52, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28741328

RESUMO

INTRODUCTION: Metatarsalgia is the most common reason for consultation in orthopedic pathology of the foot. The key to its treatment lies in the correct determination of the symptoms, which are biological, morphological and mechanical alterations responsible for pain. Weil´s osteotomy is commonly used for multiple forefoot pathologies, including metatarsalgias. MATERIAL AND METHODS: We included patients with first-line failure syndrome and associated mechanical metatarsalgia-producing deformities. The minimum follow-up was six months. All individuals were interviewed with a standardized questionnaire based on the AOFAS, a survey to know their degree of satisfaction about the surgery. RESULTS: Twelve female subjects with a mean age of 51 years were recruited between March and September of 2013. Seven right feet, five left. The AOFAS values improved only in six, in which an excellent result was obtained; five rated them as good and six as unsatisfactory. CONCLUSIONS: In a very small series, postoperative complications were observed when the shortening of the metatarsal was greater than four millimeters, with the appearance of stiffness (floating finger).


INTRODUCCIÓN: La metatarsalgia es el motivo de consulta más frecuente en patología ortopédica del pie. La clave de su tratamiento radica en la correcta determinación del síntoma, que son alteraciones biológicas, morfológicas y mecánicas responsables del dolor. La osteotomía de Weil es comúnmente utilizada para múltiples patologías del antepié, incluyendo las metatarsalgias. MATERIAL Y MÉTODOS: Se estudiaron pacientes intervenidos por síndrome de insuficiencia del primer rayo y deformidades asociadas productoras de metatarsalgia mecánica. El seguimiento mínimo fue de seis meses. Se entrevistó a todos los individuos con un cuestionario estandarizado basado en la AOFAS, una encuesta para saber su grado de satisfacción acerca de la cirugía. RESULTADOS: Se obtuvieron 12 sujetos femeninos con un promedio de 51 años de edad en el período entre Marzo y Septiembre de 2013. Siete pies derechos, cinco izquierdos. Los valores de AOFAS mejoraron sólo en seis, se obtuvo un resultado excelente; cinco los calificaron como buenos y seis como no satisfactorio. CONCLUSIONES: En una serie muy pequeña, se identificaron complicaciones postquirúrgicas cuando el acortamiento del metatarsiano es mayor a cuatro milímetros, con la aparición de rigidez (dedo flotante).


Assuntos
Ossos do Metatarso , Metatarsalgia , Osteotomia , Artrodese , Feminino , , Humanos , Metatarsalgia/cirurgia , Pessoa de Meia-Idade , Osteotomia/métodos
5.
Exp Parasitol ; 159: 107-17, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26297682

RESUMO

In higher eukaryotes, the sarco-endoplasmic reticulum (ER) Ca(2+)-ATPase (SERCA) is characterized for its high sensitivity to low concentrations of thapsigargin (TG), a very specific inhibitor. In contrast, SERCA-like enzymes with different sensitivities to TG have been reported in trypanosomatids. Here, we characterized a SERCA-like enzyme from Trypanosoma evansi and evaluated its interaction with TG. Confocal fluorescence microscopy using BODIPY FL TG and specific anti-SERCA antibodies localized the T. evansi SERCA-like enzyme in the ER and confirmed its direct interaction with TG. Moreover, the use of either 1 µM TG or 25 µM 2',5'-di (tert-butyl)-1,4-benzohydroquinone prevented the reuptake of Ca(2+) and consequently produced a small increase in the parasite cytosolic calcium concentration in a calcium-free medium, which was released from the ER pool. A 3035 bp-sequence coding for a protein with an estimated molecular mass of 110.2 kDa was cloned from T. evansi. The corresponding gene product contained all the invariant residues and conserved motifs found in other P-type ATPases but lacked the calmodulin binding site. Modeling of the three-dimensional structure of the parasite enzyme revealed that the amino acid changes found in the TG-SERCA binding pocket do not compromise the interaction between the enzyme and the inhibitor. Therefore, we concluded that T. evansi possesses a SERCA-like protein that is inhibited by TG.


Assuntos
ATPases Transportadoras de Cálcio/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Bombas de Íon/efeitos dos fármacos , Tapsigargina/farmacologia , Trypanosoma/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , ATPases Transportadoras de Cálcio/antagonistas & inibidores , ATPases Transportadoras de Cálcio/genética , ATPases Transportadoras de Cálcio/imunologia , Retículo Endoplasmático/enzimologia , Doenças dos Cavalos/parasitologia , Cavalos , Bombas de Íon/metabolismo , Masculino , Microscopia Confocal , Modelos Moleculares , Dados de Sequência Molecular , Ratos , Ratos Sprague-Dawley , Alinhamento de Sequência , Trypanosoma/efeitos dos fármacos , Trypanosoma/fisiologia , Tripanossomíase/parasitologia , Tripanossomíase/veterinária
6.
Neuroscience ; 236: 88-98, 2013 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-23380500

RESUMO

Excitability, neurite outgrowth and their specification are very important features in the establishment of neuronal differentiation. We have studied a conditioned medium (CM) from sciatic nerve which is able to induce a neuronal-like differentiation of PC12 cells. Previously, we have demonstrated that supplementing this CM with a generic inhibitor (k252a), which mainly inhibits tropomyosin-related kinase receptors (Trk receptors) and protein kinase C (PKC), caused neurite elongation, sodium current induction and axon development. In the present work, we are showing that the enhancement of neurite length and induction of sodium currents induced by CM+k252a were prevented by ErbB receptor inhibition. Additionally, we demonstrated that specific inhibition of PKC produced a similar effect to that exerted by k252a in CM-treated cells, specifically by increasing the percentage of differentiated cells with long neurites and inducing sodium currents. Moreover, CM changed the mRNA levels for ErbB2 and ErbB3 increasing them 6- and 36-folds respectively compared to their control. The inclusion of k252a with CM changed the ErbB1, ErbB2 and ErbB3 mRNA proportions increasing those eight-, seven- and fivefolds respectively. From this point, it is clear that appropriate ErbB receptor levels and PKC inhibition are necessary to enhance the effect of the CM in inducing the neuronal-like differentiation of PC12 cells. In summary, we demonstrated the involvement of ErbB receptors in the regulation of neurite elongation and sodium current induction in PC12 cells and propose that these processes could be initiated by ErbB receptors followed by a fine regulation of PKC signaling. These findings might implicate a novel interplay between ErbB receptors and PKC in the regulation of these molecular mechanisms.


Assuntos
Receptores ErbB/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Proteína Quinase C/metabolismo , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Animais , Diferenciação Celular/fisiologia , Meios de Cultivo Condicionados/farmacologia , Humanos , Imuno-Histoquímica , Potenciais da Membrana/fisiologia , Neurogênese/efeitos dos fármacos , Neurogênese/fisiologia , Neurônios/efeitos dos fármacos , Células PC12 , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
7.
Acta Ortop Mex ; 26(3): 170-3, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23320312

RESUMO

OBJECTIVE: To compare the functional and histologicalal course of two animal model groups with acute Achilles tendon tears using platelet rich plasma. MATERIAL AND METHODS: An open clinical trial was conducted with dogs donated by the animal facility of the Autonomous University of Puebla (BUAP, for its acronym in Spanish). Dogs were divided into 2 groups: a control group and a problem group. Intentional surgical Achilles tendon tear was performed to them. The Krackow technique was used to repair the tendon and the control group received platelet rich plasma (PRP) as a clot; the other group did not receive PRP. The dogs were seen at 4 weeks to check functionality using the Farell and Schwarz scale to assess the degree of limping. They were sacrificed at week 5; the tendons were removed and sent to the histopathology lab. RESULTS: Functionality results according to the Farell and Schwarz scale showed grades I and II in the problem group, and grades IV and V in the control group. Histologically, the problem group showed moderate vascular proliferation and abundant fibroblastic proliferation. The control group had mild to moderate vascular proliferation and moderate fibroblastic proliferation. CONCLUSIONS: PRP improves tendon healing and this has repercussions on functional recovery.


Assuntos
Tendão do Calcâneo/lesões , Tendão do Calcâneo/cirurgia , Plasma Rico em Plaquetas , Traumatismos dos Tendões/terapia , Animais , Terapia Combinada , Modelos Animais de Doenças , Cães , Ruptura , Traumatismos dos Tendões/cirurgia
8.
Neuroscience ; 159(2): 550-8, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19171180

RESUMO

Excitability and axon/dendrite specification are the most distinctive features in the establishment of neuronal polarization. Conditioned medium from rat sciatic nerve (CM) induced a neuronal-like morphology in PC12 cells. Here we show that CM neuritogenic activity is limited to the induction of dendrites in PC12 cells. However, treatment of these cells with CM in combination with a generic inhibitor for tyrosine kinase receptors (k252a) promoted the enhancement of neurite length, development of axons and induction of sodium currents. On the other hand, specific inhibition of TrkA and p75(NTR) receptors in CM-treated cells reduced the neurite length in comparison with cells treated only with CM, although the effect over the induction of sodium currents was continuously observed. These results suggested that CM had some components that, even though are able to start the morphological cell differentiation and produce short neurites (likely acting through TrkA and p75(NTR)), can restrain further neurite extension. Depletion of pro-NGF isoforms from CM produced a similar effect as the exerted by k252a, TrkA and p75(NTR) receptor inhibitors in CM-treated cells, inducing the elicitation of sodium currents. These results suggested that the effect of CM might be mediated through pro-NGF. The difference between the results obtained with the generic inhibitor for Trk receptors and the specific inhibitors for TrkA and p75(NTR) receptors in CM-treated cells, suggested that alternative pathways could be used to regulate neurite elongation, axon specification and sodium currents in PC12 cells. These findings represent important clues to improve the understanding of the initiation of neuronal polarity.


Assuntos
Fatores de Crescimento Neural/antagonistas & inibidores , Neuritos/fisiologia , Células PC12/citologia , Precursores de Proteínas/antagonistas & inibidores , Nervo Isquiático/química , Canais de Sódio/metabolismo , Análise de Variância , Animais , Carbazóis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Meios de Cultivo Condicionados/farmacologia , Inibidores Enzimáticos/farmacologia , Imunoprecipitação/métodos , Alcaloides Indólicos/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Fator de Crescimento Neural/farmacologia , Fatores de Crescimento Neural/metabolismo , Neuritos/efeitos dos fármacos , Proteínas de Neurofilamentos/metabolismo , Células PC12/efeitos dos fármacos , Células PC12/fisiologia , Técnicas de Patch-Clamp/métodos , Precursores de Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Fator de Crescimento Neural/antagonistas & inibidores , Receptor trkA/antagonistas & inibidores , Fatores de Tempo , Técnicas de Cultura de Tecidos
9.
Clin Transl Oncol ; 10(5): 281-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18490245

RESUMO

OBJECTIVE: To assess the effectiveness of a single dose of radio therapy (8 Gy vs. 6 Gy) plus zoledronic acid in cancer patients with bone metastases in treating pain; quality of life, time to onset of skeletal events and functional status. MATERIAL AND METHODS: A total of 139 patients from 22 Spanish hospitals were randomly assigned to: Group A, administered a single dose of 8 Gy+zoledronic acid (4 mg iv, in 15-min infusions), and Group B, administered a single dose of 6 Gy+zoledronic acid (4 mg iv, in 15-min infusions). The main variable was pain, which was assessed with the Visual Analogue Pain Scale (VAS) in supine, seated and standing positions. RESULTS: There was a total of 118 patients for intention to treat (n=67 in Group A and n=51 in Group B). The most frequent primary neoplasms were the lung (29.66%), prostate (22.03%) and breast (21.19%). Sixty patients were analysed per protocol, n=34 in group A and n=26 in group B. Improvements were observed in the VAS scores for pain in all three positions. The mean time to onset of the event was greater (p=0.0211) in Group A than in Group B (122 vs. 81.62 days). Functional status improved in Group A, and quality of life improved in both groups. CONCLUSION: The two groups achieved similar levels of pain control in supine, seated and standing positions. Quality of life also improved in both groups. However, the higher dose (8 Gy dose) in combination with zoledronic acid is associated with a longer period without skeletal events.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Difosfonatos/administração & dosagem , Imidazóis/administração & dosagem , Manejo da Dor , Radioterapia , Idoso , Neoplasias Ósseas/complicações , Terapia Combinada , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Qualidade de Vida , Ácido Zoledrônico
10.
Dis Esophagus ; 21(2): 118-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18269646

RESUMO

There is controversy in the literature regarding the motor function behavior of the lower esophageal sphincter and esophagus following partial gastrectomy. We studied 26 patients with gastric adenocarcinoma of the distal corpus and/or antrum who underwent radical subtotal gastrectomy with Roux-en-Y reconstruction. There were 15 women (57.69%) and 11 men (42.31%) with a mean age of 57.2 years; 21 were White (80.8%) and five were of African descent (19.2%). Before the surgery and 3 months afterwards, every patient underwent manometric and endoscopic examinations. The lower esophageal sphincter showed reductions in mean respiratory pressure (19.41-15.59 mmHg, P= 0.02) and maximum expiratory pressure (8.13-5.54 mmHg, P= 0.02) without significant alteration in diaphragmatic crura pressure (32.92-30.64 mmHg, P= 0.37). An increase in peristaltic wave amplitude (91.43-124.86 mmHg, P < 0.01) and peristaltic wave conduction velocity (3.29 cm/s to 4.23 cm/s; P= 0.024) were detected in esophageal function. The presence of erosive esophagitis decreased from 10 (38.46%) patients to none (P= 0.002). We concluded that following surgery the lower esophageal sphincter function was impaired, through decreased pressure in the esophageal component without alteration in diaphragmatic crura pressure. On the other hand, there was significant increase in peristaltic wave amplitude and velocity, and improvement of the erosive esophagitis. The authors suggest that subtotal gastrectomy, with gastroesophageal junction preservation, and Roux-en-Y reconstruction should be the preferred operation for distal gastric cancer to minimize esophageal dysfunction and gastroesophageal reflux disease.


Assuntos
Esfíncter Esofágico Inferior/fisiologia , Gastrectomia , Adulto , Idoso , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade
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