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2.
Environ Sci Pollut Res Int ; 29(27): 41467-41474, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35088259

RESUMO

In Egypt, antibiotic sensitivity analysis for Helicobacter pylori is not routinely performed. We aimed to identify the clarithromycin and metronidazole resistance directly from gastric biopsies for better guide treatment regimens. This cross-sectional descriptive study included 75 adult dyspeptic patients referred to the upper endoscopy unit in Suez Canal University Hospital, Ismailia, Egypt. Gastric biopsies were taken for rapid urease test (RUT) and cultured on brucella agar with antibiotic supplements. Genomic DNA was extracted directly from the specimen, and PCR was performed for direct detection of H. pylori. Also, to explore clarithromycin and metronidazole resistance, mutations in the 23S rRNA gene and the rdxA gene were investigated. We found that 60 samples were positive to RUT (80%), and only 4 samples were positive by culture. UreC gene was detected in 45 specimens. Meanwhile, 26 isolates were contained mutations at positions 2142 and 2143. Amplification of the metronidazole rdx gene was performed by conventional PCR. Out of 45 isolates, DNA sequence analysis of PCR product showed the wild type (ACA) in 9 isolates, while the mutant type (ATA) was detected in 28 isolates. We found a significant proportion of clarithromycin and metronidazole resistance among H. pylori infected patients in our region.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina/farmacologia , Estudos Transversais , Farmacorresistência Bacteriana/genética , Helicobacter pylori/genética , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana
3.
Pathogens ; 9(6)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549303

RESUMO

Today, one of the most important challenges for physicians is the adequate treatment of infections due to multidrug resistant organism (MDR). Pseudomonas aeruginosa is considered an opportunistic organism causing different types of healthcare associated infections (HAIs). We aimed to investigate the MDR and pandrug resistance (PDR) rate in P. aeruginosa in our region and detect efflux-pump mexAB genes and the proposed binding interactions of five different categories of antimicrobial agents with the mexB pump. A total of 180 non-duplicated P. aeruginosa strains were isolated from patients with HAIs in the Suez Canal University Hospital. Phenotypically, minimum inhibitory concentration (MIC) was done for all MDR and PDR strains before and after addition of efflux pump inhibitor carbonyl cyanide m-chlorophenyl hydrazone (CCCP). Molecular detection of mexA and mexB genes was done by using polymerase chain reaction (PCR). Most of the isolated strains (126 strains) were MDR (70%); only 10 samples (5.5%) were PDR. MexA and mexB genes were detected in 88.2% (120 strains) and 70.5% (96 strains) of stains, respectively. All PDR strains (10 stains) carried both mexA and mexB genes. Efflux mexAB genes were detected in all MDR and PDR strains (136 strains). Molecular modeling studies were performed to investigate the modes of intermolecular binding interactions between the antimicrobial agents and mexB key amino acids that resulted in MDR and PDR. The current study reported high prevalence of MDR and PDR P. aeruginosa in patients with HAIs in the Suez Canal University Hospitals.

4.
Int J Nanomedicine ; 12: 6973-6984, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29033565

RESUMO

As an alternative therapeutic treatment to reduce or eliminate the current side effects associated with advanced prostate cancer (PCa) chemotherapy, a multifunctional double-receptor-targeting iron oxide nanoparticles (IONPs) (luteinizing hormone-releasing hormone receptor [LHRH-R] peptide- and urokinase-type plasminogen activator receptor [uPAR] peptide-targeted iron oxide nanoparticles, LHRH-AE105-IONPs) drug delivery system was developed. Two tumor-targeting peptides guided this double-receptor-targeting nanoscale drug delivery system. These peptides targeted the LHRH-R and the uPAR on PCa cells. Dynamic light scattering showed an increase in the hydrodynamic size of the LHRH-AE105-IONPs in comparison to the non-targeted iron oxide nanoparticles (NT-IONPs). Surface analysis showed that there was a decrease in the zeta potential values for drug-loaded LHRH-AE105-IONPs compared to the NT-IONPs. Prussian blue staining demonstrated that the LHRH-AE105-IONPs were internalized efficiently by the human PCa cell line, PC-3. In vitro, magnetic resonance imaging (MRI) results confirmed the preferential binding and accumulation of LHRH-AE105-IONPs in PC-3 cells compared to normal prostate epithelial cells (RC77N/E). The results also showed that LHRH-AE105-IONPs significantly maintained T2 MRI contrast effects and reduced T2 values upon internalization by PC-3 cells. These paclitaxel-loaded double-receptor-targeting IONPs also showed an approximately twofold reduction in PC-3 cell viability compared to NT-IONPs.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Compostos Férricos/química , Nanopartículas/química , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Simulação por Computador , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Humanos , Hidrodinâmica , Concentração de Íons de Hidrogênio , Ferro/metabolismo , Imageamento por Ressonância Magnética , Masculino , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Tamanho da Partícula , Peptídeos/química , Propriedades de Superfície
5.
Am J Pathol ; 185(12): 3164-77, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26482608

RESUMO

Insulinoma-associated protein 1 (INSM1) is expressed exclusively in embryonic developing neuroendocrine (NE) tissues. INSM1 gene expression is specific for small-cell lung cancer (SCLC), along with achaete-scute homolog-like 1 (ASCL1) and several NE molecules, such as chromogranin A, synaptophysin, and neural cell adhesion molecule 1. However, the underlying biological role of INSM1 in lung cancer remains largely unknown. We first showed that surgically resected SCLC samples specifically expressed INSM1. Forced expression of the INSM1 gene in adenocarcinoma cell lines (H358 and H1975) induced the expression of ASCL1, brain-2 (BRN2), chromogranin A, synaptophysin, and neural cell adhesion molecule 1; in contrast, knockdown of the INSM1 gene by siRNA in SCLC (H69 and H889) decreased their expression. However, forced/knockdown expression of ASCL1 and BRN2 did not affect INSM1 expression. A chromatin immunoprecipitation study revealed that INSM1 bound to the promoter region of the ASCL1 gene. A xenotransplantation assay using tet-on INSM1 gene-transfected adenocarcinoma cell lines demonstrated that INSM1 induced NE differentiation and growth inhibition. Furthermore, we found that INSM1 was not expressed in non-small-cell lung cancer and some SCLC cell lines expressing Notch1-Hes1. By forced/knockdown expression of Notch1 or Hes1 genes, we revealed that Notch1-Hes1 signaling suppressed INSM1, as well as ASCL1 and BRN2. INSM1, expressed exclusively in SCLC, is a crucial regulator of NE differentiation in SCLCs, and is regulated by the Notch1-Hes1 signaling pathway.


Assuntos
Neoplasias Pulmonares/metabolismo , Células Neuroendócrinas/patologia , Proteínas Repressoras/fisiologia , Carcinoma de Pequenas Células do Pulmão/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Apoptose/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Técnicas de Silenciamento de Genes , Xenoenxertos , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/fisiologia , Humanos , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/fisiologia , Transplante de Neoplasias , Células Neuroendócrinas/metabolismo , Fatores do Domínio POU/metabolismo , Fatores do Domínio POU/fisiologia , Receptor Notch1/fisiologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais/fisiologia , Carcinoma de Pequenas Células do Pulmão/patologia , Fatores de Transcrição HES-1
6.
Mol Pharm ; 9(5): 1470-80, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22540277

RESUMO

We have previously shown that a novel microtubule-modulating noscapinoid, EM011 (9-Br-Nos), displays potent anticancer activity by inhibition of cellular proliferation and induction of apoptosis in prostate cancer cells and preclinical mice models. However, physicochemical and cellular barriers encumber the development of viable formulations for future clinical translation. To circumvent these limitations, we have synthesized EM011-cyclodextrin inclusion complexes to improve solubility and enhance therapeutic index of EM011. Phase solubility analysis indicated that EM011 formed a 1:1 stoichiometric complex with ß-CD and methyl-ß-CD, with a stability constant (K(c)) of 2.42 × 10(-3) M and 4.85 × 10(-3) M, respectively. Fourier transform infrared spectroscopy suggested the penetrance of either a O-CH(2) or OCH(3)-C(6)H(4)-OCH(3) moiety of EM011 in the ß-CD or methyl-ß-CD cavity. In addition, multifarious techniques, namely, differential scanning calorimetry, powder X-ray diffraction, scanning electron microscopy, NMR spectroscopy, and computational studies validated the cage complex of EM011 with ß-CD and methyl-ß-CD. Moreover, rotating frame overhauser enhancement spectroscopy showed that the H(a) proton of the OCH(3)-C(6)H(4)-OCH(3) moiety was in close proximity with H3 proton of the ß-CD or methyl-ß-CD cavity. Furthermore, we found that the solubility of EM011 in phosphate buffer saline (pH 7.4) was enhanced by ~11 fold and ~21 fold upon complexation with ß-CD and methyl-ß-CD, respectively. The enhanced dissolution of the drug CD-complexes in aqueous phase remarkably decreased their IC(50) to 28.5 µM (9-Br-Nos-ß-CD) and 12.5 µM (9-Br-Nos-methyl-ß-CD) in PC-3 cells compared to free EM011 (~200 µM). This is the first report to demonstrate the novel construction of cylcodextrin-based nanosupramolecular vehicles for enhanced delivery of EM011 that warrants in vivo evaluation for the superior management of prostate cancer.


Assuntos
Ciclodextrinas/química , Noscapina/química , Noscapina/farmacologia , Neoplasias da Próstata/metabolismo , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dioxóis/química , Dioxóis/uso terapêutico , Humanos , Isoquinolinas/química , Isoquinolinas/uso terapêutico , Espectroscopia de Ressonância Magnética , Masculino , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
J Control Release ; 149(3): 314-22, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21047537

RESUMO

The tubulin-binding anticancer activity of noscapine, an orally available plant-derived anti-tussive alkaloid, has been recently identified. Noscapine inhibits tumor growth in nude mice bearing human xenografts of hematopoietic, breast, lung, ovarian, brain and prostate origin. Despite its nontoxic attributes, significant elimination of the disease has not been achieved, perhaps since the bioavailability of noscapine to tumors saturates at an oral dose of 300 mg/kg body weight. To enable the selective and specific delivery of noscapine to prostate cancer cells, we have engineered a multifunctional nanoscale delivery vehicle that takes advantage of urokinase plasminogen activator receptor (uPAR) overexpression in prostate cancer compared to normal prostate epithelia and can be tracked by magnetic resonance imaging (MRI) and near-infrared (NIR) imaging. Specifically, we employed the human-type 135 amino-acid amino-terminal fragment (hATF) of urokinase plasminogen activator (uPA), a high-affinity natural ligand for uPAR. Noscapine (Nos) was efficiently adsorbed onto the amphiphilic polymer coating of uPAR-targeted nanoparticles (NPs). Nos-loaded NPs were uniformly compact-sized, stable at physiological pH and efficiently released the drug at pH 4 to 5 within a span of 4h. Our results demonstrate that these uPAR-targeted NPs were capable of binding to the receptor and were internalized by PC-3 cells. uPAR-targeted Nos-loaded NPs enhanced intracellular noscapine accumulation as evident by the ~6-fold stronger inhibitory effect on PC-3 growth compared to free noscapine. In addition, Nos-loaded iron oxide NPs maintained their T2 MRI contrast effect upon internalization into tumor cells owing to their significant susceptibility effect in cells. Thus, our data provide compelling evidence that these optically and magnetic resonance imaging (MRI)-trackable uPAR-targeted NPs may offer a great potential for image-directed targeted delivery of noscapine for the management of prostate cancer.


Assuntos
Antineoplásicos/administração & dosagem , Antitussígenos/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Noscapina/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antitussígenos/farmacocinética , Antitussígenos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Nanopartículas/ultraestrutura , Noscapina/farmacocinética , Noscapina/farmacologia , Próstata/efeitos dos fármacos , Próstata/patologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética
8.
J Magn Magn Mater ; 322(2): 190-196, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20161408

RESUMO

The delivery of noscapine therapies directly to the site of the tumor would ultimately allow higher concentrations of the drug to be delivered, and prolong circulation time in vivo to enhance the therapeutic outcome of this drug. Therefore, we sought to design magnetic based polymeric nanoparticles for the site directed delivery of noscapine to invasive tumors. We synthesized Fe(3)O(4) nanoparticles with an average size of 10 ± 2.5 nm. These Fe(3)O(4) NPs were used to prepare noscapine loaded magnetic polymeric nanoparticles (NMNP) with an average size of 252 ± 6.3 nm. Fourier transform infrared (FT-IR) spectroscopy showed the encapsulation of noscapine on the surface of the polymer matrix. The encapsulation of the Fe(3)O(4) NPs on the surface of the polymer was confirmed by elemental analysis. We studied the drug loading efficiency of polylactide acid (PLLA) and poly (L-lactide acid-co-gylocolide) (PLGA) polymeric systems of various molecular weights. Our findings revealed that the molecular weight of the polymer plays a crucial role in the capacity of the drug loading on the polymer surface. Using a constant amount of polymer and Fe(3)O(4) NPs, both PLLA and PLGA at lower molecule weights showed higher loading efficiencies for the drug on their surfaces.

9.
Regul Pept ; 148(1-3): 88-94, 2008 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18455815

RESUMO

The enteric nervous system (ENS: myenteric and submucosal plexuses) of the gastrointestinal tract may have a role in the reduction of food intake by cholecystokinin (CCK). Exogenous cholecystokinin-8 (CCK-8) activates the myenteric plexus and the feeding control areas of the dorsal vagal complex (DVC) of the brainstem. An increasing number of reports, however, have shown that CCK-58 is the sole or the major circulating form of CCK in rat, human and dog, and that it is qualitatively different from CCK-8 in evoking various gastrointestinal physiological responses (e.g., contraction of the gallbladder and exocrine pancreatic secretion). In the current report, we compared the abilities of exogenous CCK-58 to activate the myenteric plexus and the dorsal vagal complex with those of exogenous CCK-8 by quantifying Fos-like immunoreactivity (Fos-LI; a marker for neuronal activation). We report that CCK-58 (1, 3, and 5 nmol/kg) increased Fos-LI in the myenteric plexus (p<0.001) and in the DVC (p<0.001) compared to the saline vehicle. The highest dose of CCK-58 increased Fos-LI more than an equimolar dose of CCK-8 in the myenteric plexus and the area postrema. Thus, CCK-8 and CCK-58 produce the same qualitative pattern of activation of central and peripheral neurons, but do not provoke identical quantitative patterns at higher doses. The different patterns produced by the two peptides at higher doses, in areas open to the circulation (myenteric plexus and area postrema) may reflect endocrine actions not observed at lower doses.


Assuntos
Colecistocinina/farmacologia , Plexo Mientérico/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Nervo Vago/efeitos dos fármacos , Animais , Colecistocinina/administração & dosagem , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Imuno-Histoquímica , Plexo Mientérico/citologia , Plexo Mientérico/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Nervo Vago/citologia , Nervo Vago/metabolismo
10.
Brain Res ; 1205: 27-35, 2008 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-18346716

RESUMO

We compared the abilities of cholecystokinin-33 (CCK-33) and CCK-8 to reduce food intake and to activate feeding-related areas of the nervous system. (1) Overnight food-deprived rats were presented with a 10% sucrose solution, and intake was measured at 5-min intervals throughout a 90-min test beginning immediately after intraperitoneal injections of 1, 3, or 5 nMol/kg of CCK-33, CCK-8, or the vehicle control. In the initial 20 min (first meal), both peptides were equally effective, producing large reductions of food intake. Thereafter, however, CCK-33 was more effective than CCK-8, producing much more sustained reductions. Overall, both peptides reduced total food intake, but CCK-33 was more effective than CCK-8. (2) Possible roles for the myenteric plexus of the duodenum and the dorsal vagal complex (DVC) of the brainstem in the differential satiety effects of CCK-33 and CCK-8 were examined by quantifying CCK-33- and CCK-8-stimulated Fos-like immunoreactivity (Fos-LI) in each site. Consistent with the greater ability of CCK-33 to produce sustained inhibitions of food intake, CCK-33 produced more Fos-LI than CCK-8 in nearly every section of the sampled sites. The results demonstrate: (1) Different forms of CCK have different efficacies in reducing food intake; (2) CCK-33 produces a much more prolonged satiety action than CCK-8; and (3) the myenteric plexus and DVC may play roles in these differential satiety actions.


Assuntos
Depressores do Apetite/farmacologia , Colecistocinina/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Nervo Vago/efeitos dos fármacos , Animais , Contagem de Células , Imuno-Histoquímica , Masculino , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Núcleo Solitário/citologia , Núcleo Solitário/efeitos dos fármacos
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