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1.
Physiol Mol Biol Plants ; 27(2): 189-201, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33707862

RESUMO

Freezing stress is a serious environmental factor that obstructs plant development. The root endophytic fungus Piriformospora indica has proved to be effective to confer abiotic stress tolerance to host plants. To investigate how P. indica improves freezing tolerance, we compared the expression profiles of P. indica-colonized and uncolonized Arabidopsis seedlings either exposed to freezing stress or not. Nearly 24 million (93.5%) reads were aligned on the Arabidopsis genome. 634 genes were differentially expressed between colonized and uncolonized Arabidopsis exposed to freezing stress. Interestingly, 193 Arabidopsis genes did not respond to freezing stress but were up-regulated by P. indica under freezing stress. Freezing stress-responsive genes encoded various members of the WRKY, ERF, bHLH, HSF, MYB and NAC transcription factor families. The qRT-PCR analyses confirmed the high-throughput sequencing results for 28 genes. Functional enrichment analysis indicated that the fungus mainly controls genes for freezing-stress related proteins involved in lipid and ion transport, metabolism pathways and phytohormone signaling. Our findings identified novel target genes of P. indica in freezing-stress exposed plants and highlight the benefits of the endophyte for plants exposed to a less investigated environmental threat. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s12298-020-00922-y) contains supplementary material, which is available to authorized users.

2.
Molecules ; 25(19)2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33036293

RESUMO

A novel series of some hydrazones bearing thiazole moiety were generated via solvent-drop grinding of thiazole carbohydrazide 2 with various carbonyl compounds. Also, dehydrative-cyclocondensation of 2 with active methylene compounds or anhydrides gave the respective pyarzole or pyrazine derivatives. The structures of the newly synthesized compounds were established based on spectroscopic evidences and their alternative syntheses. Additionally, the anti-viral activity of all the products was tested against SARS-CoV-2 main protease (Mpro) using molecular docking combined with molecular dynamics simulation (MDS). The average binding affinities of the compounds 3a, 3b, and 3c (-8.1 ± 0.33 kcal/mol, -8.0 ± 0.35 kcal/mol, and -8.2 ± 0.21 kcal/mol, respectively) are better than that of the positive control Nelfinavir (-6.9 ± 0.51 kcal/mol). This shows the possibility of these three compounds to effectively bind to SARS-CoV-2 Mpro and hence, contradict the virus lifecycle.


Assuntos
Antivirais/síntese química , Betacoronavirus/enzimologia , Hidrazonas/síntese química , Inibidores de Proteases/síntese química , Pirazinas/síntese química , Pirazóis/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/farmacologia , Betacoronavirus/química , Betacoronavirus/efeitos dos fármacos , Sítios de Ligação , COVID-19 , Proteases 3C de Coronavírus , Infecções por Coronavirus/tratamento farmacológico , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Descoberta de Drogas , Humanos , Hidrazonas/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pandemias , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Pirazinas/farmacologia , Pirazóis/farmacologia , SARS-CoV-2 , Termodinâmica , Interface Usuário-Computador , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
3.
Plant Signal Behav ; 15(4): 1745472, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32228382

RESUMO

The root endophytic fungus Piriformospora indica plays an important role in increasing abiotic stress tolerance of its host plants. To explore the impact of P. indica on freezing tolerance, Arabidopsis seedlings were co-cultivated with P. indica exposed to -6°C for 6 h. Freezing stress decreased the survival rate, electrolyte leakage, leaf temperature, water potential and chlorophyll fluorescence of Arabidopsis plants in comparison to the controls. P. indica colonizion reduced the negative effects of freezing, and the plants contained also higher amounts of soluble proteins, proline and ascorbic acid during the post-thaw recovery period (4°C; 12 h). In contrast, the H2O2 and malondialdehyde levels were reduced in seedlings colonized by the fungus. The brassinolide (BR) and abscisic acid (ABA) levels dramatically increased and the transcript levels of several crucial freezing-stress related genes (CBFs, CORs, BZR1, SAG1 and PYL6) were higher in inoculated plants during the post-thaw recovery period. Finally, inocculated mutants impaired in the freezing tolerance response (such as ice1 for INDUCER OF CBF EXPRESSION1, a crucial basic helix-loop-helix transcription factor for the cold-response pathway in Arabidopsis, cbf1, -2, -3 for C-REPEAT-Binding Factor, cor47 and -15 for COLD-REGULATED and siz1 encoding the SUMO E3 LIGASE) showed better survival rates and higher expression levels of freezing-related target genes after freezing compared to the inocculated controls. Our results demonstrate that P. indica confers freezing tolerance and better post-thaw recovery in Arabidopsis, and stimulates the expression of several genes involved in the CBF-dependent pathway.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Arabidopsis/microbiologia , Basidiomycota/fisiologia , Congelamento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Antioxidantes/metabolismo , Proteínas de Arabidopsis/metabolismo , Clorofila/metabolismo , Fluorescência , Íons , Mutação/genética , Fenótipo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Temperatura , Água
4.
Molecules ; 24(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717217

RESUMO

A novel series of thiazole-based heterocycles was synthesized using 1,3-dipolar cycloaddition reactions in the presence of chitosan-grafted-poly(vinylpyridine) as an eco-friendly biopolymeric basic catalyst. The molecular structure of the synthesized compounds was illustrated by spectroscopic and elemental analysis. Various in vitro biological assays were performed to explore the potential antitumor, antimicrobial and hepatoprotective activities of the newly synthesized compounds. The cytotoxic activities were assessed against human hepatocellular carcinoma (HepG-2), colorectal carcinoma (HCT-116) and breast cancer (MCF-7) cell lines and results revealed that all compounds displayed antitumor activities with the chlorine-containing derivatives, 11c and 6g, being the most potent. The majority of the tested thiazole derivatives exhibited satisfactory antibacterial activity towards the used gram positive and gram-negative bacterial species. Moreover, many derivatives showed weak hepatoprotective activity against CCl4-induced hepatotoxicity.


Assuntos
Antibacterianos/síntese química , Antineoplásicos/síntese química , Tetracloreto de Carbono/antagonistas & inibidores , Química Verde , Compostos Heterocíclicos/síntese química , Tiazóis/síntese química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Tetracloreto de Carbono/toxicidade , Catálise , Quitosana/química , Reação de Cicloadição , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Células HCT116 , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Concentração Inibidora 50 , Células MCF-7 , Testes de Sensibilidade Microbiana , Polivinil/química , Cultura Primária de Células , Piridinas/química , Relação Estrutura-Atividade , Tiazóis/farmacologia
5.
Chem Cent J ; 11(1): 25, 2017 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29086817

RESUMO

BACKGROUND: Thiazoles and 1,3,4-thiadiazoles have been reported to possess various pharmacological activities. RESULTS: A novel series of thiazoles carrying 1,3,4-thiadiazole core were designed and prepared via the reaction of the 2-(4-methyl-2-phenylthiazole-5-carbonyl)-N-phenylhydrazinecarbo-thioamide with the appropriate hydrazonoyl chlorides. The structures of the newly synthesized compounds were confirmed based on elemental and spectral analysis as well as their alternative syntheses. The cytotoxic potency of the newly synthesized thiadiazoles was evaluated by their growth inhibitory potency in liver HepG2 cancer cell line. Also, the structure activity relationship was studied. CONCLUSIONS: All the newly synthesized compounds were evaluated for their anticancer activity against liver carcinoma cell line (HepG2) using MTT assay. The results revealed that the compounds 12d, 12c, 6g, 18b, 6c, and 6f (IC50 = 0.82, 0.91, 1.06, 1.25, 1.29 and 1.88 µM, respectively) had good antitumor activity against liver carcinoma cell line (HepG2) when compared with the standard drug Doxorubicin (IC50 = 0.72 µM). Graphical abstract A facile synthesis and anticancer activity of some novel thiazoles carrying 1,3,4-thiadiazole moiety.

6.
Chem Cent J ; 11(1): 105, 2017 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-29086869

RESUMO

BACKGROUND: Many heterocyclic compounds containing thiazole or 1,3,4-thiadiazole ring in their skeletons have been reported to possess various pharmacological activities especially anticancer activities. RESULTS: 4-Methyl-2-phenylthiazole-5-carbohydrazide (2) was used as a synthon to prepare 2-(4-methyl-2-phenylthiazole-5-carbonyl)-N-phenylhydrazinecarbothioamide (3) and 2-(2-(4-methyl-2-phenylthiazole-5-carbonyl)hydrazono)-N'-phenylpropane hydrazonoyl chlorides 5a-c. In addition, thioamide 3 was used as starting material for preparation of a new series of thiadiazole derivatives via its reaction with hydrazonoyl chlorides 5a-c in dioxane using triethylamines as catalyst. In addition, a series of thiazole derivatives was synthesized by reaction of thioamide 3 with a number of α-halo compounds, namely, 3-chloropentane-2,4-dione (8) or 2-chloro-3-oxo-N-phenyl butanamide (10) phenacyl bromide 12 ethyl chloroacetate (14) in EtOH in the presence of triethylamine. The structures assigned for all the new products were elucidated based on both elemental analyses and spectral data and the mechanisms of their formation was also discussed. Moreover, the new products was evaluated in vitro by MTT assays for their anticancer activity against cell lines of Hepatocellular carcinoma cell line (HepG-2). The best result observed for compounds 7b (IC50 = 1.61 ± 1.92 (µg/mL)) and 11 (IC50 = 1.98 ± 1.22 (µg/mL)). The structure-activity relationships have been suggested based on their anticancer results. CONCLUSIONS: A novel series of new pharmacophores containing thiazole moiety have been synthesized using a facile and convenient methods and evaluated as potent anticancer agents.

7.
Biochem Biophys Res Commun ; 490(4): 1162-1167, 2017 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-28668394

RESUMO

Piriformospora indica is an endophytic fungus colonizing roots of a wide variety of plants. Previous studies showed that P. indica promotes early flowering and plant growth in the medicinal plant Coleus forskohlii. To determine the impact of P. indica on flowering time in Arabidopsis, we co-cultivated the plants with P. indica under long day condition. P. indica inoculated Arabidopsis plants displayed significant early flowering phenotype. qRT-PCR analysis of colonized plants revealed an up-regulation of flowering regulatory (FLOWERING LOCUS T, LEAFY, and APETALA1) and gibberellin biosynthetic (Gibberellin 20-Oxidase2, Gibberellin 3-Oxidase1 and Gibberellin requiring1) genes, while the flowering-repressing gene FLOWERING LOCUS C was down regulated. Quantification of gibberellins content showed that the colonization with P. indica caused an increase in GA4 content. Compared to wild-type plants, inoculation of the Arabidopsis ga5 mutant affected in gibberellin biosynthetic gene led to less pronounced changes in the expression of genes regulating flowering and to a lower increase in GA4 content. Taken together, our data indicate that P. indica promotes early flowering in Arabidopsis likely by increasing gibberellin content.


Assuntos
Arabidopsis/metabolismo , Basidiomycota/metabolismo , Endófitos/metabolismo , Flores/metabolismo , Giberelinas/biossíntese , Raízes de Plantas/metabolismo , Arabidopsis/microbiologia , Flores/microbiologia , Raízes de Plantas/microbiologia
8.
Middle East J Dig Dis ; 9(1): 49-54, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28316766

RESUMO

Laterally spreading tumors (LSTs) are generally defined as superficial lesions ≥10 mm in diameter that typically extend laterally rather than vertically along the colonic wall. Such lesions are now increasingly reported because of increased awareness and the introduction of chromo and magnifying colonoscopy. Although the clinicopathological characteristics and the efficacy of endoscopic management of LSTs have been defined in Japanese cohorts, reports from the Middle East are lacking where surgical resection is the mainstay of treatment. We report a case with an LST about 20 cm from anal verge removed by endoscopic mucosal resection. After histopathological evaluation of the removed specimen, we categorized the patient as having high risk early colon cancer. The intensive follow-up as an additional treatment strategy was chosen for the patient. This review addresses the management of early carcinoma in colorectal polyp with reference to proper preoperative assessment, treatment selection with special attention to role of biomarkers, the need for additional treatment on the basis of the presence of risk factors and endoscopic follow-up after treatment.

9.
Mini Rev Med Chem ; 17(9): 805-815, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28019641

RESUMO

METHOD: A series of novel thiazole derivatives were synthesized in a good yield via reaction of 2-(1-(4-methyl-2-phenylthiazol-5-yl)ethylidene)hydrazine carbothioamide with hydrazonoyl halides. The reaction was performed in the presence of DABCO as an organocatalyst in short reaction times, easy workup, good to excellent yields. The structure of the newly synthesized products was elucidated via elemental analysis, spectral data and alternative routes whenever possible. Ten compounds were evaluated for their anti-cancer activity against the colon carcinoma cell line (HCT-116). RESULTS & CONCLUSION: The results revealed that most of the tested compounds showed high or moderate anti-cancer activity. The molecular docking of five novel thiazolyl-thiazole derivatives was performed by the Molecular Operating Environment (MOE) program.


Assuntos
Antineoplásicos/farmacologia , Citotoxinas/farmacologia , Simulação de Acoplamento Molecular , Tiazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Citotoxinas/síntese química , Citotoxinas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
10.
Neuroepidemiology ; 45(2): 100-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26314301

RESUMO

BACKGROUND: There is lack of knowledge on the epidemiological characteristics of brain tumors in Middle Eastern countries. The objective of this study was to study the epidemiological features of primary brain tumors in Jordan. METHODS: We conducted a prospective cohort study incorporating data from 16 hospitals in Jordan during a 1 year period (May 1, 2011-April 30, 2012). All primary brain tumors diagnosed in Jordan during the study period were identified. The following parameters were retrieved from patients' files: age, gender, histological type, and location. The demographic data of the country was obtained from the National Department of Statistics. RESULTS: A total of 313 primary brain tumors were identified during the study period. The incidence of primary brain tumors in Jordan among the general population was 5.01 per 100,000 person-years (5.38 in females and 4.65 in males). The incidence in pediatric, adult, and elderly patients was 2.09, 7.29, and 14.38 per 100,000 person-years, respectively. The most common histological types were meningioma (26.2%), glioblastoma (18.9%), astrocytoma (14.1%), and pituitary adenoma (9.3%). CONCLUSIONS: The incidence of primary brain tumors in the Jordanian population is relatively low, in part due to the young age of the general population.


Assuntos
Astrocitoma/epidemiologia , Neoplasias Encefálicas/epidemiologia , Meningioma/epidemiologia , Neoplasias Hipofisárias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Glioblastoma/epidemiologia , Humanos , Incidência , Lactente , Jordânia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
11.
J Pediatr Surg ; 45(11): 2210-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21034946

RESUMO

PURPOSE: Laparoscopic hernia repair in infancy and childhood is still debatable. There are many techniques available for laparoscopic hernia repair in children. The objective of this study was to compare intracorporeal suturing and knotting with extracorporeal knotting for repair of congenital inguinal hernia in infants and children about operative time, recurrence rate, hydrocele formation, and postoperative cosmetic results. A randomized controlled study was carried out in the Pediatric Surgery Unit of Al-Azhar University Hospitals (Cairo, Egypt) over a 3-year period. PATIENTS AND METHODS: One hundred fifty patients with congenital inguinal hernia were randomized into 2 equal groups (n = 75). Group A was subjected to intracorporeal purse string suture around the internal inguinal ring (IIR) using 2 needle holders. Group B was subjected to insertion of purse string suture around IIR using a Reverdin needle (RN) and extracorporeal knotting. Inclusion criteria included bilateral inguinal hernia, recurrent hernia, hernia in obese children, incarcerated hernia, and ipsilateral hernia with questionable hernia on the contralateral side. Exclusion criteria included unilateral inguinal hernia and hernia with undescended testicles. The main outcome measurements were operative time, length of hospital stay, postoperative hydrocele formation, recurrence rate, and cosmetic results. RESULTS: There were no significant differences about age, sex, and mode of presentation between both groups. All cases were completed successfully without conversion. There were significant statistical differences in the operative time, recurrence rate, and cosmetic results between the studied groups, whereas there were no significant statistical differences in the hospital stay and postoperative hydrocele formation. CONCLUSION: Laparoscopic hernia repair by RN is an effective method of hernia repair in infants and children. It resulted in a marked reduction of operative time and excellent cosmetic results with low recurrence.


Assuntos
Hérnia Inguinal/cirurgia , Laparoscopia/métodos , Agulhas , Técnicas de Sutura/instrumentação , Pré-Escolar , Desenho de Equipamento , Feminino , Seguimentos , Hérnia Inguinal/congênito , Humanos , Lactente , Recém-Nascido , Ligadura/instrumentação , Masculino , Estudos Prospectivos , Prevenção Secundária , Resultado do Tratamento
12.
Pediatr Surg Int ; 26(8): 807-13, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20532893

RESUMO

PURPOSE: Rectal prolapse in children without underlying conditions is usually a self-limiting problem and requires no surgical treatment. For children with persistent rectal prolapse, a variety of surgical procedures have been described with success. Recently, there are many reports addressing the successful use of different laparoscopic approaches for complete rectal prolapse. We present a novel simplified laparoscopic technique for management of those patients. The aim of this study is to evaluate the results that can be achieved by using this technique in management of persistent complete rectal prolapse in children. METHODS: We reviewed the reports of 680 patients with primary complete and partial rectal prolapse over the period from August 2000 to August 2008. Fifty-two patients with complete primary rectal prolapse refractory to medical treatment for 2 years underwent a novel simplified technique for laparoscopic mesh rectopexy. RESULTS: Conservative management was successful with no recurrences in 628 patients (92.4%) while 52 (7.6%) patients did not respond to conservative management at a median follow-up period of 2 years. They were 35 males and 17 females. Their ages ranged from 2 to 14 years (mean 6). All patients were subjected to laparoscopic mesh rectopexy successfully without any conversion. The mean duration of surgery was 40 min. No intraoperative complications were reported, but one patient developed postoperative constipation that responded well to conservative treatment. The mean postoperative hospitalization was 2 days. Two cases were lost to follow-up, while the others were available for 36 months. There was no recurrence. CONCLUSION: Laparoscopy mesh rectopexy is safe, rapid, effective technique. It improved functional outcome without recurrence. It is associated with minimal postoperative pain and short hospital stay with excellent cosmoses.


Assuntos
Laparoscopia/métodos , Prolapso Retal/cirurgia , Telas Cirúrgicas , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Tempo de Internação/estatística & dados numéricos , Masculino , Dor Pós-Operatória/prevenção & controle , Complicações Pós-Operatórias , Resultado do Tratamento
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