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1.
Recent Pat Biotechnol ; 18(1): 52-62, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38205774

RESUMO

BACKGROUND: Cancer is among the leading causes of death worldwide, imposing high costs on the health systems of all societies. Extensive biological studies are required to discover appropriate therapies. Escherichia coli has long been regarded as one of the main biotechnological bio-factories to produce recombinant protein-based therapeutics. In the present study, five strains of E. coli were compared to achieve the maximum production of a previously designed recombinant immunotoxin-carrying MAP30 toxin against VEGF-overexpressed cancer cells in a benchtop bioreactor. METHODS: The recombinant immunotoxin coding gene sequence was extracted from the NCBI database. The host used to produce the recombinant immunotoxin were five E. coli strains of BL21 (DE3), DH5α, SHuffle®T7, XL1-Blue, and Rosetta-gamiTM (DE3). CaCl2 method was used for bacterial transformation. Bacterial growth measurements were performed using optical density measurements at 600 nm. The immunotoxin production was measured using SDS-PAGE analysis. The best-producing strain was cultivated in a 10-L benchtop stirred tank bioreactor. Recent patents on this field were also studied. RESULTS: The results demonstrated that the BL21 (DE3) strain had the highest expression of recombinant protein in comparison to other strains. Moreover, the cell growth of E. coli BL21 (DE3) and SHuffle®T7 strains before transformation in the LB medium, were significantly higher in comparison to other strains. Additionally, the transformation of Rosettagami was associated with decreased cell proliferation. The transformation of the XL1-Blue strain did not effect cell growth. Analysis of the growth kinetics demonstrated appropriate proliferation of the transformed BL21 (DE3) cells in the laboratory benchtop bioreactor. CONCLUSIONS: Based on the results of this study, the BL21 (DE3) strain could be used as a suitable host for the production of the recombinant immunotoxin against VEGF in stirred tank bioreactor, which can be employed for the treatment of tumors. Yet, its precise mechanism must be explored in extensive studies.


Assuntos
Escherichia coli , Imunotoxinas , Escherichia coli/genética , Imunotoxinas/genética , Fator A de Crescimento do Endotélio Vascular/genética , Patentes como Assunto , Reatores Biológicos , Proteínas Recombinantes/genética
5.
J Dent (Shiraz) ; 21(4): 307-313, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33344681

RESUMO

STATEMENT OF THE PROBLEM: Some patients may report moderate-to-severe pain and/or swelling following root canal treatment, which is undesirable for both the patient and dentist and may require an unscheduled emergency visit by patients to relieve their symptoms. PURPOSE: The aim of this study was to evaluate the post-treatment flare-up incidence following application of nano zinc oxide-eugenol (NZOE) sealer in mandibular first molars with irreversible pulpitis. MATERIALS AND METHOD: This single-blinded study was performed on 60 patients having mandibular first molars with irreversible pulpitis. After signing the written consent form, the patients were randomly divided into two groups considering their age range (20-34 and 35-50 years). Individuals without systemic diseases and with a first mandibular molar diagnosed with irreversible pulpitis due to caries, no sinus track and abscess, normal periapical radiographic appearance, no spontaneous pre-treatment pain, not taken any medication for at least 8 hours before the treatment visit were included in this study. Patients of both sexes with age range of 20 to 50 years were selected. In order to obturate the root canal space, AH26 sealer was used in the one group and the synthesized NZOE was applied in another group. The patients were then given questionnaires to report the severity of pain and presence of swelling during 6, 18, 24, and 48 hours of follow-up. The data was analyzed using SPSS v.19 software applying repeated measures ANOVA. The significance level was set at 0.05. RESULTS: The severity of pain was significantly lower in NZOE group at 24 hours post-treatment (p= 0.003). Patients reported no symptoms of swelling in any group. CONCLUSION: NZOE sealer manifested satisfactory results and could be regarded as a promising substitute to routine sealers since patients may experience less pain during the first hours after receiving root canal therapy.

6.
Neural Netw ; 132: 155-165, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32890787

RESUMO

The structure of the brain network exhibits modularity at multiple spatial scales. The effect of the modular structure on the brain dynamics has been the focus of several studies in recent years but many aspects remain to be explored. For example, it is not well-known how the delays in the transmission of signals between the neurons and the brain regions interact with the modular structure to determine the brain dynamics. In this paper, we show an important impact of the delays on the collective dynamics of brain networks with modular structure; that is, the degree of the synchrony between different brain regions depends on the oscillating frequency. In particular, we show that when increasing the frequency of the nodes the network transits from a global synchrony state to an asynchronous state, through a transition region over which the local synchrony inside the modules is stronger than the global synchrony. When the delays depend on the distance between the nodes, the modular structure of different spatial scales appears in the correlation matrix over different specific frequency bands, so that, finer spatial modular structures reveal in higher frequency bands. The results are corroborated by a simple theoretical argument and elaborated by simulations on several simplified modular networks and the connectome with different spatial resolutions.


Assuntos
Encéfalo/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Redes Neurais de Computação , Humanos , Neurônios/fisiologia , Fatores de Tempo
7.
Sci Rep ; 10(1): 3306, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094415

RESUMO

The collective behaviour of neural networks depends on the cellular and synaptic properties of the neurons. The phase-response curve (PRC) is an experimentally obtainable measure of cellular properties that quantifies the shift in the next spike time of a neuron as a function of the phase at which stimulus is delivered to that neuron. The neuronal PRCs can be classified as having either purely positive values (type I) or distinct positive and negative regions (type II). Networks of type 1 PRCs tend not to synchronize via mutual excitatory synaptic connections. We study the synchronization properties of identical type I and type II neurons, assuming unidirectional synapses. Performing the linear stability analysis and the numerical simulation of the extended Kuramoto model, we show that feedforward loop motifs favour synchronization of type I excitatory and inhibitory neurons, while feedback loop motifs destroy their synchronization tendency. Moreover, large directed networks, either without feedback motifs or with many of them, have been constructed from the same undirected backbones, and a high synchronization level is observed for directed acyclic graphs with type I neurons. It has been shown that, the synchronizability of type I neurons depends on both the directionality of the network connectivity and the topology of its undirected backbone. The abundance of feedforward motifs enhances the synchronizability of the directed acyclic graphs.


Assuntos
Rede Nervosa/fisiologia , Neurônios/fisiologia , Animais , Retroalimentação , Modelos Neurológicos
10.
11.
Iran Endod J ; 14(3): 216-219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-36814943

RESUMO

For a successful root canal treatment, it is critical for a clinician to have complete knowledge of the root canal morphology. There are numerous cases in literature concerning the unusual anatomy of mandibular first molars. This report presents a case of a mandibular first molar with three distal canals. An overview of the types and numbers of the common anatomic forms of this tooth also is presented, as is a summary of published anomalies.

12.
Wounds ; 30(9): 263-268, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30256753

RESUMO

INTRODUCTION: Aloe vera is sometimes used as a folk remedy for minor wounds and burns, but its mechanisms of action in wound healing are unclear. OBJECTIVE: In this study, the authors evaluate the effects of A vera on wound healing. MATERIALS AND METHODS: In vitro analyses of cell proliferation and migration were conducted on normal human primary skin fibroblasts and keratinocytes in growth media with A vera solution and preservatives at various concentrations. Growth media with preservatives but without A vera solution served as the control. RESULTS: Aloe vera had significant stimulatory effects on cell proliferation and migration of both fibroblasts and keratinocytes. Surprisingly, A vera also exhibited strong protective effects on preservative-induced keratinocyte death. Keratinocytes in the growth media with both the preservatives and A vera had dramatically higher viability than cells in the control media without A vera. CONCLUSIONS: The results suggest A vera accelerates wound healing by promoting the proliferation and migration of fibroblasts and keratinocytes and by protecting keratinocytes from preservative-induced death.


Assuntos
Aloe/química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Humanos , Técnicas In Vitro , Queratinócitos/citologia , Fitoterapia
13.
Iran Endod J ; 12(2): 220-225, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28512490

RESUMO

INTRODUCTION: The aim of this in vitro study was to evaluate the cytotoxicity of a new nano zinc-oxide eugenol (NZOE) sealer on human gingival fibroblasts (HGFs) compared with Pulpdent (micro-sized ZOE sealer) and AH-26 (resin-based sealer). METHODS AND MATERIALS: The Pulpdent, AH-26, and NZOE sealers were prepared and exposed to cell culture media immediately after setting, and 24 h and one week after setting. Then, the primary cultured HGFs were incubated for 24 h with different dilutions (1:1 to 1:32) of each sealer extract. Cell viability was evaluated by methyl thiazolyl diphenyl tetrazolium bromide (MTT) assay. The results were compared using two-way analysis of variance followed by Tukey's post hoc test. The level of significance was set at 0.05. RESULTS: All sealer extracts, up to 32 times dilutions, showed cytotoxicity when exposed to HGF immediately after setting. The extracts obtained 24 h or one week after setting showed lower cytotoxicity than extracts obtained immediately after setting. At all setting times, NZOE showed lower cytotoxicity than Pulpdent and AH-26. While one-week extracts of NZOE had no significant effect on the viability of HGF at dilutions 1:4 to 1:32, both Pulpdent and AH-26 decreased the cell viability at dilutions of 1:4 and 1:8. CONCLUSION: NZOE exhibited lower cytotoxicity compared to Pulpdent and AH-26 on HGF and has the potential to be considered as a new root canal filling material.

14.
Iran J Basic Med Sci ; 20(2): 172-177, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28293394

RESUMO

OBJECTIVES: The purpose of the present study was the immunohistochemical evaluation of VEGF and VII factors in dog's teeth pulp revascularized with MTA and propolis. MATERIALS AND METHODS: 144 mature and immature two rooted dog's premolar canals were selected. Pulp necrosis and infection were established after 2 weeks and the disinfection of the canals was done with copious NaOCl irrigation and triantibiotic mixture (ciprofloxacin, metronidazole, and minocycline) for 3 weeks. Subsequently, the blood clot was evoked in the canal by periapical tissue irritation with a k-file. The samples were randomly divided into 6 experimental groups: propolis (groups 1, 2), MTA (groups 3, 4), and parafilm (groups 5, 6) in immature and mature teeth. The animals were sacrificed and samples were prepared for immunohistochemical evaluation of VEGF and the VIII factor. RESULTS: Tissue regeneration was seen in 64.5% of MTA, 38% of propolis, and 0% of parafilm group samples. Expression of VEGF and VIII factor in the propolis group was more than the MTA group and it showed a reduction after 3 months in comparison to 1 month. VEGF and VIII factor were seen in stromal cells in addition to endothelial vessel cells. Overall, expression of angiogenic factors was more in the open apex teeth compared to close apex ones. CONCLUSION: According to the results of this study, propolis can induce the expression of VEGF and VIII factor in infected mature and immature dog's teeth and is a suitable biomaterial for the revascularization technique.

15.
Iran Endod J ; 12(1): 64-69, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28179927

RESUMO

INTRODUCTION: The aim of this animal study was to evaluate the histological response of the new nano zinc-oxide eugenol (NZOE) sealer in comparison with Pulp Canal Sealer (ZOE based) and AH-26 (epoxy resin sealer). METHODS AND MATERIALS: A total of 27 Wistar rats were used. Four polyethylene tubes were implanted in the back of each rat (three tubes containing the test materials and an empty tube as a control). Then, 9 animals were sacrificed at each interval of 15, 30 and 60 days, and the implants were removed with the surrounding tissues.Samples were evaluated for the presence of inflammatory cell (mononuclear cell), vascular changes, fibrous tissue formation and present of giant cell. Comparisons between groups and time-periods were performed using the Kruskal-Wallis and Mann-Whitney U non-parametric tests. The level of significance was set at 0.05. RESULTS: No significant difference was observed in tissue reactions and biocompatibility pattern of three sealers during 3 experimental periods (P<0.05). In all groups the tissue behavior showed tendency to decrease the irritation effect over time. Conclusion: The new nano zinc-oxide eugenol sealer has histocompatibility properties comparable to conventional commercial sealers.

16.
Iran Endod J ; 12(1): 74-77, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28179929

RESUMO

INTRODUCTION: A desirable quality of any endodontic sealer is its ability to be tooth color friendly. Therefore the aim of the present study was to evaluate the tooth discoloration potential of a nano zinc oxide-eugenol (NZOE) sealer. METHODS AND MATERIALS: In order to evaluate tooth discoloration, the pulp chamber of 60 human maxillary central and lateral incisors were filled with one of the sealers, naming AH-26 (resin-based sealer), Pulpdent sealer (ZOE-based) and a NZOE experimental sealer. Color measurements was assessed at the baseline (before placement of sealers) (T0), 24 h (T1) and 72 h (T2) h, 1-week (T3), and 1-month (T4) after the placement of sealers using the Easy Shade spectrophotometer. Data were analyzed in SPSS software using one-way ANOVA, and repeated measured ANOVA. RESULTS: No significant differences were observed when the paired comparison test was performed (P>0.05). CONCLUSION: The tested NZOE sealer had similar tooth discoloration potential in comparison with AH-26 and ZOE sealer.

17.
Lasers Surg Med ; 49(1): 27-39, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27114071

RESUMO

BACKGROUND AND OBJECTIVES: Androgenetic alopecia (AGA) affects 50% of males by age 50 and 50% of females by age 80. Recently, the use of low-level laser therapy (LLLT) has been proposed as a treatment for hair loss and to stimulate hair regrowth in AGA. This paper aims to review the existing research studies to determine whether LLLT is an effective therapy for AGA based on objective measurements and patient satisfaction. STUDY DESIGN: A systematic literature review was done to identify articles on Medline, Google Scholar, and Embase that were published between January 1960 and November 2015. All search hits were screened by two reviewers and examined for relevant abstracts and titles. Articles were divided based on study design and assessed for risk of bias. RESULTS: Eleven studies were evaluated, which investigated a total of 680 patients, consisting of 444 males and 236 females. Nine out of 11 studies assessing hair count/hair density found statistically significant improvements in both males and females following LLLT treatment. Additionally, hair thickness and tensile strength significantly improved in two out of four studies. Patient satisfaction was investigated in five studies, and was overall positive, though not as profound as the objective outcomes. CONCLUSION: The majority of studies covered in this review found an overall improvement in hair regrowth, thickness, and patient satisfaction following LLLT therapy. Although we should be cautious when interpreting these findings, LLLT therapy seems to be a promising monotherapy for AGA and may serve as an effective alternative for individuals unwilling to use medical therapy or undergo surgical options. Lasers Surg. Med. 49:27-39, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Alopecia/radioterapia , Cabelo/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Satisfação do Paciente/estatística & dados numéricos , Adulto , Alopecia/diagnóstico , Estética , Feminino , Cabelo/crescimento & desenvolvimento , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
18.
Int J High Risk Behav Addict ; 5(3): e30127, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27803892

RESUMO

INTRODUCTION: Ingestion of foreign bodies has been previously reported in some patients with schizophrenia. This behavior may be a manifestation of delusional beliefs or a response to command hallucinations and can lead to severe complications. CASE PRESENTATION: This paper reports a patient with schizophrenia who, as a manifestation of his illness, ingested a metallic skewer to kill ademon inside his abdomen that he believed was controlling him. As a result, he developed an acute intestinal perforation and underwent surgery. CONCLUSIONS: It is of a great importance to closely monitor the therapy compliance of patients suffering from mental illnesses. This will benefit them by preventing some of the serious complications of their disease, which may include life-threatening conditions such as intestinal perforation that needs surgical intervention.

19.
Bull Tokyo Dent Coll ; 57(2): 57-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27320294

RESUMO

The purpose of this study was to compare the biocompatibility of two types of calcium hydroxide paste in subcutaneous tissue in rat. Twenty-two Wistar rats were divided into 4 experimental (n=5 each) and one control (n=2) group. A polyethylene tube filled with either Dentsply or Sure-Paste was implanted in each rat in the experimental groups, while an empty polyethylene tube was used in the control group. After 15 or 60 days, the animals were sacrificed and histopathological examination carried out. Tissue reaction was assessed by inflammatory cell infiltration using a 4-point scoring system, ranging from 0 to 3. Data were analyzed with the Kruskal-Wallis, Wilcoxon, and McNemar tests. Both types of paste induced an inflammatory response at each time point, although the intensity varied. A significant reduction in the number of inflammatory cells was observed at 60 days. Dentsply appeared to induce a more marked inflammatory response at both time points, although the difference was not significant. These results suggest that both types of paste are biocompatible with subcutaneous tissue in rat.


Assuntos
Hidróxido de Cálcio/efeitos adversos , Hidróxido de Cálcio/farmacologia , Inflamação/etiologia , Teste de Materiais/métodos , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/patologia , Animais , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/farmacologia , Colágeno/efeitos dos fármacos , Edema/etiologia , Fibroblastos/efeitos dos fármacos , Fibrose/etiologia , Granulócitos/efeitos dos fármacos , Granulócitos/imunologia , Inflamação/imunologia , Necrose/etiologia , Fagócitos/efeitos dos fármacos , Fagócitos/imunologia , Polimetil Metacrilato/efeitos adversos , Polimetil Metacrilato/farmacologia , Distribuição Aleatória , Ratos , Ratos Wistar , Materiais Restauradores do Canal Radicular/efeitos adversos , Materiais Restauradores do Canal Radicular/farmacologia , Tela Subcutânea/imunologia
20.
Lepr Rev ; 87(1): 101-3, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27255063

RESUMO

Leprosy (Hansen's disease) is a chronic contagious granulomatous disease principally affecting the skin and peripheral nervous system, caused by Mycobacterium leprae. In this report, we present a case of autochthonous leprosy in a man from Florida as the first human case reported from this region. Authors believe dermatologists need to be aware of the possibility of autochthonous transmission of leprosy in the Eastern-Southern United States, and should consider leprosy in any patient with atypical skin lesions, even when a history of contact with armadillo is missing.


Assuntos
Hanseníase Tuberculoide/classificação , Hanseníase Tuberculoide/diagnóstico , Idoso , Dapsona/administração & dosagem , Dapsona/uso terapêutico , Florida/epidemiologia , Humanos , Hansenostáticos/administração & dosagem , Hansenostáticos/uso terapêutico , Hanseníase Tuberculoide/tratamento farmacológico , Hanseníase Tuberculoide/epidemiologia , Masculino , Rifampina/administração & dosagem , Rifampina/uso terapêutico
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