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1.
Curr Pharm Des ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38818919

RESUMO

Gene editing technology, particularly Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has transformed medical research. As a newly developed genome editing technique, CRISPR technology has strongly assisted scientists in enriching their comprehension of the roles of individual genes and their influences on a vast spectrum of human malignancies. Despite considerable progress in elucidating obesity's molecular pathways, current anti-obesity medications fall short in effectiveness. A thorough understanding of the genetic foundations underlying various neurobiological pathways related to obesity, as well as the neuro-molecular mechanisms involved, is crucial for developing effective obesity treatments. Utilizing CRISPR-based technologies enables precise determination of the roles of genes that encode transcription factors or enzymes involved in processes, such as lipogenesis, lipolysis, glucose metabolism, and lipid storage within adipose tissue. This innovative approach allows for the targeted suppression or activation of genes regulating obesity, potentially leading to effective weight management strategies. In this review, we have provided a detailed overview of obesity's molecular genetics, the fundamentals of CRISPR/Cas9 technology, and how this technology contributes to the discovery and therapeutic targeting of new genes associated with obesity.

2.
J Pharm Sci ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432623

RESUMO

The objective of this investigation was to develop a self-assembled, dual-functionalized delivery system that could effectively transport doxorubicin (DOX) to cancer cells through the use of AS1411 aptamer and hyaluronic acid polymer (HA). The ultimate goal is an improved targeting approach for more efficient treatment. The core of this system comprised polyethylenimine (PEI) and FOXM1 aptamer, which was coated by HA. Next, nucleolin targeting aptamers (AS1411) were loaded onto the nanocomplex. Afterward, DOX was added to Aptamers (Apts)-HA-PEI-FOXM1 NPs to create the DOX-AS1411-HA-PEI-FOXM1 NPs for better treatment of cancer cells. The cytotoxic effect of the nanocomplex on L929, 4T1, and A549 cells showed that cell mortality in target cancer cells (4T1 and A549) was considerably enhanced compared to nontarget cells (L929, normal cells). The findings from the flow cytometry analysis and fluorescence imaging demonstrated the cellular absorption of DOX-Apts-HA-PEI-FOXM1 NPs in target cells was significantly enhanced when compared to L929 cells. Furthermore, in vivo antitumor study exhibited that DOX-Apts-HA-PEI-FOXM1 NPs rendered specific tumor accumulation and increasing of the anti-tumor effects.

3.
Prog Mol Biol Transl Sci ; 204: 45-67, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38458743

RESUMO

Unhealthy lifestyles have given rise to a growing epidemic of metabolic liver diseases, including nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). NAFLD often occurs as a consequence of obesity, and currently, there is no FDA-approved drug for its treatment. However, therapeutic oligonucleotides, such as RNA interference (RNAi), represent a promising class of pharmacotherapy that can target previously untreatable conditions. The potential significance of RNAi in maintaining physiological homeostasis, understanding pathogenesis, and improving metabolic liver diseases, including NAFLD, is discussed in this article. We explore why NAFLD/NASH is an ideal target for therapeutic oligonucleotides and provide insights into the delivery platforms of RNAi and its therapeutic role in addressing NAFLD/NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/terapia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Interferência de RNA , Cirrose Hepática , Oligonucleotídeos/uso terapêutico
4.
Nurs Ethics ; 31(1): 79-88, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37257094

RESUMO

BACKGROUND: Nursing is a humanitarian and social field that provides health services. It combines science and art and has a rich history. Despite fundamental changes in the provision of medical services and nursing education, the concept of "good nurse" is still unclear. PURPOSE: The purpose of this article is to investigate the characteristics of a good nurse from the nurses' perspective. RESEARCH DESIGN AND METHOD: A qualitative study was applied using conventional content analysis. The participants were 30 nurses that selected with purposive sampling method. Data were collected through unstructured interviews and simultaneously analyzed via the conventional content analysis approach of Graneheim and Lundman. ETHICAL CONSIDERATIONS: This study was approved by the Research Ethics Committee of Hormozgan University of Medical Sciences, Iran. FINDINGS: The study revealed that personal characteristics (Adherence to ethical and human principles, Physical health, Attractive appearance, and Ability to communicate properly); and professional characteristics (knowledge - clinical skill - nursing roles) are essential to being a good nurse. CONCLUSION: Coming to know the distinctive features of a good nurse as perceived by nurses themselves creates an opportunity for nurses to rethink their profession and to reflect on the characteristics of the good nurse.


Assuntos
Educação em Enfermagem , Ética em Enfermagem , Enfermeiras e Enfermeiros , Humanos , Pesquisa Qualitativa , Papel do Profissional de Enfermagem , Irã (Geográfico)
5.
Drug Dev Ind Pharm ; 49(10): 648-657, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37772892

RESUMO

OBJECTIVE: Herein, a dual-targeting delivery system using mesoporous silica nanoparticles with hollow structures (HMSNs) was developed for the specific delivery of epirubicin (EPI) to cancer cells and introducing a H+-triggered bubble generating nanosystem (BGNS). HMSNs containing EPI are covered by hyaluronic acid (HA) shell and AS1411 aptamer to create the BGNS-EPI-HA-Apt complex, which is highly selective against CD44 marker and nucleolin overexpressed on the surface of tumor cells. METHODS: MTT assay compared the cytotoxicity of different treatments in CHO (Chinese hamster ovary) cells as well as 4T1 (murine mammary carcinoma) and MCF-7 (human breast adenocarcinoma) cells. The internalization of Epi was assessed by flow cytometry along with fluorescence imaging. In vivo studies were conducted on BALB/c mice bearing a tumor from 4T1 cell line where monitoring included measuring tumor volume, mouse weight changes over time alongside mortality rate; accumulation levels for Epi within organs were also measured during this process. RESULTS: The collected data illustrated that BGNS-EPI-HA-Apt complex controlled the release of EPI in a sustained method. Afterward, receptor-mediated internalization via nucleolin and CD44 was verified in 4T1 and MCF-7 cells using fluorescence microscopy assay and flow cytometry analysis. The results of tumor inhibitory effect study exhibited that BGNS-EPI-HA-Apt complex decreased off-target effect and improved on-target effects because of its targeting ability. CONCLUSION: The data acquired substantiates that HA-surface modified HMSNs functionalized with aptamers possess significant potential as a focused platform for efficient transportation of anticancer agents to neoplastic tissues.


Assuntos
Neoplasias da Mama , Nanopartículas , Cricetinae , Humanos , Animais , Camundongos , Feminino , Ácido Hialurônico , Células CHO , Sistemas de Liberação de Medicamentos/métodos , Linhagem Celular Tumoral , Cricetulus , Dióxido de Silício/química , Epirubicina , Nanopartículas/química , Células MCF-7 , Neoplasias da Mama/tratamento farmacológico
6.
J Caring Sci ; 12(1): 42-49, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37124405

RESUMO

Introduction: The COVID-19 pandemic is now a major public health crisis in the world. Nurses as key members of professional are exposed the most challenges caused by COVID19. Knowledgeable nurses' experiences can provide appropriate solutions to increase the quality of care and improve the health of the society. This study aimed to explore the lived experiences of nurses' caring for patients with COVID-19. Methods: 12 nurses participated in this phenomenological study. We performed purposeful sampling and in-depth face-to-face and semi-structured individual interviews for collecting data. Qualitative data, was analyzed by the 6-step Van Manen hermeneutic phenomenology. Results: After data analysis, the mean (SD) age of study participants was 32.25 (5.62) years and their mean work experience was 9.75 (5.39) years. From the analysis of data obtained from interviews with nurses working in COVID-19 wards, 1050 primary codes, 17 subthemes and 5 themes were extracted. Main themes include: sincere service, patient oppression, emotional instability, suspension and relaxation. Conclusion: Analysis of data in this study suggested that the nurses who care patients in COVID-19 pandemic, faced many professional and psychological challenges. Healthcare managers should plan for psychological support services for the nurses.

7.
Polymers (Basel) ; 15(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36904404

RESUMO

Self-assembly is a growth mechanism in nature to apply local interactions forming a minimum energy structure. Currently, self-assembled materials are considered for biomedical applications due to their pleasant features, including scalability, versatility, simplicity, and inexpensiveness. Self-assembled peptides can be applied to design and fabricate different structures, such as micelles, hydrogels, and vesicles, by diverse physical interactions between specific building blocks. Among them, bioactivity, biocompatibility, and biodegradability of peptide hydrogels have introduced them as versatile platforms in biomedical applications, such as drug delivery, tissue engineering, biosensing, and treating different diseases. Moreover, peptides are capable of mimicking the microenvironment of natural tissues and responding to internal and external stimuli for triggered drug release. In the current review, the unique characteristics of peptide hydrogels and recent advances in their design, fabrication, as well as chemical, physical, and biological properties are presented. Additionally, recent developments of these biomaterials are discussed with a particular focus on their biomedical applications in targeted drug delivery and gene delivery, stem cell therapy, cancer therapy and immune regulation, bioimaging, and regenerative medicine.

8.
J Neurosci Methods ; 383: 109736, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349568

RESUMO

Brain-computer interfaces (BCIs) have achieved significant success in controlling external devices through the Electroencephalogram (EEG) signal processing. BCI-based Motor Imagery (MI) system bridges brain and external devices as communication tools to control, for example, wheelchair for people with disabilities, robotic control, and exoskeleton control. This success largely depends on the machine learning (ML) approaches like deep learning (DL) models. DL algorithms provide effective and powerful models to analyze compact and complex EEG data optimally for MI-BCI applications. DL models with CNN network have revolutionized computer vision through end-to-end learning from raw data. Meanwhile, RNN networks have been able to decode EEG signals by processing sequences of time series data. However, many challenges in the MI-BCI field have affected the performance of DL models. A major challenge is the individual differences in the EEG signal of different subjects. Therefore, the model must be retrained from the scratch for each new subject, which leads to computational costs. Analyzing the EEG signals is challenging due to its low signal to noise ratio and non-stationary nature. Additionally, limited size of existence datasets can lead to overfitting which can be prevented by using transfer learning (TF) approaches. The main contributions of this study are discovering major challenges in the MI-BCI field by reviewing the state of art machine learning models and then suggesting solutions to address these challenges by focusing on feature selection, feature extraction and classification methods.


Assuntos
Interfaces Cérebro-Computador , Aprendizado Profundo , Humanos , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Algoritmos , Imaginação
9.
Anal Chim Acta ; 1219: 340031, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35715136

RESUMO

Herein, a facile fluorescent CRISPR-Cas12a-based sensing strategy is presented for prostate specific antigen (PSA), as a prostate cancer biomarker, with the assistance of a cruciform DNA nanostructure and PicoGreen (PG) as a fluorochrome. Highly sensitive recognition of PSA is one of the virtues of the proposed method which comes from the use of unique features of both CRISPR-Cas12a and DNA structure in the design of the aptasensor. The presence of PSA creates a cruciform DNA nanostructure in the sample which can be loaded by PG and make sharp fluorescence emission. While, when there is no PSA, the CRISPR-Cas12a digests sequences 1 and 3 as single-stranded DNAs, causing no DNA structure and a negligible fluorescence is detected after addition of PG. This aptasensor presents a sensitive recognition performance with detection limit of 4 pg/mL and a practical use for determination of PSA in serum samples. So, this analytical strategy introduces a convenient and highly sensitive approach for detection of disease biomarkers.


Assuntos
Técnicas Biossensoriais , Antígeno Prostático Específico , Técnicas Biossensoriais/métodos , Sistemas CRISPR-Cas , DNA/genética , DNA Cruciforme , Humanos , Masculino
10.
Cell Mol Biol Lett ; 27(1): 50, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715738

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), a major international public health concern. Because of very similar amino acid sequences of the seven domain names, SARS-CoV-2 belongs to the Coronavirinae subfamily of the family Coronaviridae, order Nidovirales, and realm Riboviria, placed in exceptional clusters, but categorized as a SARS-like species. As the RNA virus family with the longest genome, the Coronaviridae genome consists of a single strand of positive RNA (25-32 kb in length). Four major structural proteins of this genome include the spike (S), membrane (M), envelope (E), and the nucleocapsid (N) protein, all of which are encoded within the 3' end of the genome. By engaging with its receptor, angiotensin-converting enzyme 2 (ACE2), SARS-CoV-2 infects host cells. According to the most recent epidemiological data, as the illness spread globally, several genetic variations of SARS-CoV-2 appeared quickly, with the World Health Organization (WHO) naming 11 of them. Among these, seven SARS-CoV-2 subtypes have received the most attention. Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), and Omicron (B.1.617.2) are now designated as variations of concern (VOC) (B.1.1.529). Lambda (C.37) and Mu are variations of interest (VOI) (B.1.621). The remaining six are either being monitored or are no longer considered a threat. On the basis of studies done so far, antiviral drugs, antibiotics, glucocorticoids, recombinant intravenous immunoglobulin, plasma therapy, and IFN-α2b have been used to treat patients. Moreover, full vaccination is associated with lower infection and helps prevent transmission, but the risk of infection cannot be eliminated completely in vaccinated people.


Assuntos
COVID-19 , SARS-CoV-2 , Genótipo , Humanos , Peptidil Dipeptidase A , Fenótipo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
11.
Carbohydr Polym ; 292: 119691, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725215

RESUMO

A facile method was designed that can specifically deliver CRISPR/Cas9 into target cells nuclei and reduce the off-target effects. A multifunctional delivery vector for FOXM1 knockout was composed by integration of cell targeting polymer (hyaluronic acid) and cell and nuclear targeting group (AS1411 aptamer) on the surface of nanoparticles formed by genome editing plasmid and chitosan (CS) as the core (Apt-HA-CS-CRISPR/Cas9). The data of cytotoxicity experiment and western blot confirmed this issue. The results of flow cytometry analysis and fluorescence imaging demonstrated that Apt-HA-CS-CRISPR/Cas9 was significantly internalized into target cells (MCF-7, SK-MES-1, HeLa) but not into nontarget cells (HEK293). Furthermore, the in vivo studies displayed that the Apt-HA-CS-CRISPR/Cas9 was strongly rendered tumor inhibitory effect and delivered efficiently CRISPR/Cas9 into the tumor with no detectable distribution in other organs compared with naked plasmid. This approach provides an avenue for specific in vivo gene editing therapeutics with the lowest side effect.


Assuntos
Sistemas CRISPR-Cas , Quitosana , Aptâmeros de Nucleotídeos , Sistemas CRISPR-Cas/genética , Técnicas de Transferência de Genes , Células HEK293 , Humanos , Ácido Hialurônico , Oligodesoxirribonucleotídeos
12.
Biotechnol Lett ; 44(5-6): 713-728, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35412165

RESUMO

OBJECTIVES: To improve the expression efficiency of recombinant hFIX, by enhancing its γ-carboxylation, which is inhibited by Calumenin (CALU), we used intronic artificial microRNAs (amiRNAs) for the CALU downregulation. METHODS: Two human CALU (hCALU)-specific amiRNAs were designed, validated and inserted within a truncated form of the hFIX intron 1, in either 3'- or 5'-untranslated regions of the hFIX cDNA, in an expression vector. After transfections of a human cell line with the recombinant constructs, processing of the miRNAs confirmed by RT-PCR, using stem-loop primers. The hFIX and hCALU expression assessments were done based on RT-PCR results. The Gamma(γ)-carboxylation of the expressed hFIX was examined by a barium citrate precipitation method, followed by Enzyme-Linked Immunosorbent Assay. RESULTS: Efficient CALU down regulations, with more than 30-fold decrease, occurred in the cells carrying either of the two examined the 3'-located amiRNAs. The CALU downregulation in the same cells doubled the FIX γ-carboxylation, although the transcription of the FIX decreased significantly. On the other hand, while the expression of the amiRNAs from the 5'-located intron had no decreasing effect on the expression level of CALU, the level of hFIX transcription in these cells increased almost twofold compared to the construct without amiRNA. CONCLUSION: The CALU downregulation, consistent with efficient hFIX γ-carboxylation, occurred in the cells carrying either of the two amiRNAs containing constructs, although it was affected by the locations of the amiRNA carrying introns, suggesting a possible need to optimize the conditions for the amiRNAs expression.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Fator IX , MicroRNAs , Linhagem Celular , Fator IX/metabolismo , Vetores Genéticos , Humanos , Íntrons/genética , MicroRNAs/genética , Transfecção
13.
Comput Biol Med ; 143: 105288, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35168083

RESUMO

In the Motor Imagery (MI)-based Brain Computer Interface (BCI), users' intention is converted into a control signal through processing a specific pattern in brain signals reflecting motor characteristics. There are such restrictions as the limited size of the existing datasets and low signal to noise ratio in the classification of MI Electroencephalogram (EEG) signals. Machine learning (ML) methods, particularly Deep Learning (DL), have overcome these limitations relatively. In this study, three hybrid models were proposed to classify the EEG signal in the MI-based BCI. The proposed hybrid models consist of the convolutional neural networks (CNN) and the Long-Short Term Memory (LSTM). In the first model, the CNN with different number of convolutional-pooling blocks (from shallow to deep CNN) was examined; a two-block CNN model not affected by the vanishing gradient descent and yet able to extract desirable features employed; the second and third models contained pre-trained CNNs conducing to the exploration of more complex features. The transfer learning strategy and data augmentation methods were applied to overcome the limited size of the datasets by transferring learning from one model to another. This was achieved by employing two powerful pre-trained convolutional neural networks namely ResNet-50 and Inception-v3. The continuous wavelet transform (CWT) was used to generate images for the CNN. The performance of the proposed models was evaluated on the BCI Competition IV dataset 2a. The mean accuracy vlaues of 86%, 90%, and 92%, and mean Kappa values of 81%, 86%, and 88% were obtained for the hybrid neural network with the customized CNN, the hybrid neural network with ResNet-50 and the hybrid neural network with Inception-v3, respectively. Despite the promising performance of the three proposed models, the hybrid neural network with Inception-v3 outperformed the two other models. The best obtained result in the present study improved the previous best result in the literature by 7% in terms of classification accuracy. From the findings, it can be concluded that transfer learning based on a pre-trained CNN in combination with LSTM is a novel method in MI-based BCI. The study also has implications for the discrimination of motor imagery tasks in each EEG recording channel and in different brain regions which can reduce computational time in future works by only selecting the most effective channels.

14.
Carbohydr Polym ; 248: 116735, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919550

RESUMO

Herein, a nanotherapeutic delivery method was presented for co-delivery of doxorubicin (DOX) and aptamer against Forkhead box M1 (FOXM1 Apt) to cancer cells. Firstly, the vehicle composed of chitosan (CS)-Gold nanoparticles (AuNPs) conjugate was prepared. Nucleolin aptamer (AS1411) and FOXM1 Apt were loaded onto the CS-AuNPs and formed Aptamers (Apts)-CS-AuNPs. Subsequently, DOX was added to the Apts-CS-AuNPs to obtain the DOX-Apts-CS-AuNPs complex for synergistic treatment of tumor. The data of flow cytometry analysis and fluorescence imaging displayed that the complex was effectively internalized into target cells (A549 and 4T1 cells, nucleolin+) but not into CHO cells as nontarget cells. The results of the MTT assay showed that the complex significantly increased cell mortality in 4T1 and A549 cells compared to CHO cells treated with the complex. The in vivo studies demonstrated that the DOX-Apts-CS-AuNPs complex exhibited more tumor inhibitory effect and less distribution in other organs compared to free DOX.


Assuntos
Aptâmeros de Nucleotídeos/administração & dosagem , Quitosana/química , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Ouro/química , Nanopartículas Metálicas/química , Neoplasias Experimentais/tratamento farmacológico , Células A549 , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/farmacocinética , Células CHO , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Proteína Forkhead Box M1/genética , Humanos , Nanopartículas Metálicas/ultraestrutura , Camundongos Endogâmicos BALB C , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Fosfoproteínas/química , Fosfoproteínas/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Nucleolina
15.
J Clin Apher ; 35(2): 72-78, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31899560

RESUMO

OBJECTIVE: Effects of therapeutic plasma exchange (TPE) on immune cells and their cytokine production in MS, are unknown. Since interleukine-6 and tumor growth factor-ß have critical roles in MS immunopathogenesis, the impacts of TPE on the expression of these cytokines and their receptors on the surface of CD4+ T lymphocytes, were investigated. METHODS: Blood cells were obtained from 30 Relapsing-Remitting (RR) MS patients, before and after a complete TPE course. Cytokines mRNA and their receptor expression on the CD4+ T cells surface were assessed using real-time PCR and flowcytometry, respectively. RESULTS: TPE reduced symptom severity (P = .01) and the relief was higher in males than in females (P = .039). TPE also increased TGF-ß mRNA and decreased IL-6 receptor expressing cells frequency (P = .009 and P = .028, respectively). Moreover, the frequency of CD4+IL6R+ T cells was positively correlated with disease severity (P = .001). CONCLUSION: TPE impacts simultaneously on the TGF-ß mRNA and IL-6 receptor expression, and this may be a mechanism of improvement in MS relapse symptoms induced by the TPE.


Assuntos
Interleucina-6/sangue , Esclerose Múltipla Recidivante-Remitente/sangue , Troca Plasmática/métodos , Fator de Crescimento Transformador beta1/sangue , Adolescente , Adulto , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular , Feminino , Humanos , Leucócitos Mononucleares/citologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Recidiva , Fatores Sexuais , Linfócitos T Reguladores/citologia , Células Th17/citologia , Resultado do Tratamento , Adulto Jovem
16.
RSC Adv ; 10(51): 30314-30397, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35559005

RESUMO

In this review we focus on applications of alkyl orthoesters as valuable and efficient substrates to perform various classes of two-component and multi-component organic reactions. The article has classified them according to two aspects, which are: (i) a focus on the reaction medium (solvent-free conditions, aqueous media, and organic solvents); and (ii) an examination of product structures. Reaction accomplishment under solvent-free conditions is an eco-friendly process with the absence of volatile toxic solvents, which puts it in line with green chemistry goals. Water is an interesting choice in organic transformations due to its inexpensiveness and safety. The authors hope their assessment will help chemists to attain new approaches for utilizing alkyl orthoesters in various organic synthetic methods. The review covers the corresponding literature up to the beginning of 2020.

17.
Curr Org Synth ; 16(1): 38-69, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31965922

RESUMO

BACKGROUND: Pentaerythritol (2,2-bis (hydroxymethyl) propane-1,3-diol) as white crystalline odorless solid has been synthesized in 1891. Pentaerythritol is multifaceted species in many compounds, which are wildly utilized in medicine and industry. Also, multicomponent reactions (MCRs) play a crucial role in organic and medicinal chemistry. Hence, in these reactions, pentaerythritol is a versatile substrate for the synthesis of many polyfunctionalized products, because of the presence of the neopentane core and one hydroxyl group in each of the four terminal carbons. OBJECTIVE: The review describes pentaerythritol multicomponent reactions in the presence of different solvents in the reaction medium to produce various compounds including pentaerythritols. This review covers the literature relevant up to 2018. CONCLUSION: It is obvious from the provided review that a great deal of research has been done in this field, utilizing various mediums (solvent-free conditions, aqueous media, and organic solvents) for the synthesis of the products of containing pentaerythritols. This classification is based on the importance of economic and environmental friendly reactions. Due to the whole aforesaid reports, some reactions required heat for their progress, and some others were accompanied by microwave or ultrasonic waves.

18.
Electron Physician ; 9(9): 5380-5387, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29038725

RESUMO

BACKGROUND: The care demands of children with chronic diseases can affect caregivers' health by imposing caregiving burden to them. The health status of caregivers plays a vital role in the quality of care provided to such children and in their quality of life. OBJECTIVE: To determine caregiving burden in caregivers and to identify relevant influential factors. METHODS: In this cross-sectional study, a total number of 249 caregivers of children with chronic diseases who referred to hospitalization and ambulatory departments of Bandar Abbas, Iran in 2016 were selected using convenience sampling method. The main caregivers who were older than 18 years and provided care to a sick child for at least three months consecutively were included. Caregiving burden was measured using the Caregiver Burden Scale. Data was analyzed SPSS 16 using descriptive statistics, Spearman's correlation coefficient and Mann-Whitney U test. RESULTS: Mean score of caregiving burden was 1.98 which was close to moderate level. The highest caregiving burden was observed in general strain dimension (2.35), and cerebral palsy imposed the maximum burden to caregivers (2.24). Correlation coefficient revealed that perceived caregiving burden was in connection with children's and caregivers' age, duration of disease and caregiving, child's level of disability, number of family members and income level (p<0.05). Mann-Whitney U test showed that female caregivers, villagers, and caregivers dealing with more than one patient experienced higher burden (p<0.05). CONCLUSION: Different variables can increase caregiving burden. Therefore, planning for holistic and family-centered interventions to decrease caregiving burden is necessary for health care providers.

19.
Electron Physician ; 9(1): 3611-3615, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28243414

RESUMO

INTRODUCTION: Prolonged pregnancy is associated with increased risk of pregnancy complications. The role of body mass index (BMI) is not completely identified in the risk of occurrence of prolonged pregnancy. The aim of this study was to determine the association between BMI and duration of pregnancy in woman referred to the Shariati Maternity Hospital in Bandar Abbas (Hormozgan Province, Iran). METHODS: This cross-sectional study was carried out on 1100 pregnant women referred to the Shariati Hospital in Bandar Abbas in 2015. Gestational age determined by last menstrual period (LMP) or first-trimester ultra-sonography. The women were divided into two groups of less than 40 weeks of gestation and more than 40 weeks of gestation. The women were divided based on their BMI at the first trimester of pregnancy into four groups, including less than normal, normal, overweight, and excess weight. Data were analyzed using ANOVA, Mann-Whitney test, and chi-square test by SPSS version 16.0. RESULTS: The average age of mothers studied was 23 ± 4.30 years. Average of gestational age was 39 ± 1.85 weeks. Among the study participants 1020 (92.7%) had term pregnancies, 53 (4.8%) had preterm pregnancies, and 27 (2.5%) had post-term pregnancies. Also among the study participants, 40% had a BMI less than 19.8 kg/m2, 45.9% had BMI between 19.8 and 26 kg/m2, and 9.8% had BMI between 26.1 and 29 kg/m2, and 4.3% had BMI less than 29 kg/m2. Mean BMI was 20.95 ± 4.02 for women with gestational age of equal to or less than 40 weeks and 23.34 ± 4.52 for women with gestational age of more than 40 weeks. Duration of pregnancy was significantly higher in women with higher BMI at the first trimester (p<0.00006). CONCLUSION: High BMI of a mother in the first trimester of pregnancy is associated with prolonged pregnancy and may increase the risk of post-term pregnancy. Women are recommended to reach an ideal weight before pregnancy to decrease the risk of the pregnancy complications.

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