Gene Silencing Therapeutics in Cardiology: A Review Article

Abstract Therapeutics that inhibit enzymes, receptors, ion channels, and cotransporters have long been the mainstay of cardiovascular medicine. Now, oligonucleotide therapeutics offer a modern variation on this paradigm of protein inhibition. Rather than target a protein, however, small interfering ribonucleic acids and antisense oligonucleotides target the messenger RNA (mRNA) from which a protein is translated. Endogenous, cellular mechanisms enable the oligonucleotides to bind a selected sequence on a target mRNA, leading to its degradation. The catalytic nature of the process confers an advantage over the stoichiometric binding of traditional small molecule therapeutics to their respective protein targets. Advances in nucleic acid chemistry and delivery have enabled development of oligonucleotide therapeutics against a wide range of diseases, including hyperlipidemias and hereditary transthyretin-mediated amyloidosis with polyneuropathy. While most of these therapeutics were initially designed for rare diseases, recent clinical trials highlight the potential impact of oligonucleotides on more common forms of cardiovascular disease.

Os LncRNAs Estão Envolvidos no Processo de Aterosclerose em Diversos Níveis / LncRNAs are Involved in the Process of Atherosclerosis at Diverse Levels

Resumo A aterosclerose é a causa mais comum de doença cardiovascular em todo o mundo, ela está associada a uma alta incidência de eventos clínicos. O acúmulo de evidências elucidou que os RNAs longos não codificantes (LncRNAs) são uma nova classe de transcritos com papéis críticos nos processos fisiopatológicos da aterosclerose. Nesta revisão, resumimos o progresso recente dos LncRNAs no desenvolvimento da aterosclerose. Descrevemos principalmente os diversos mecanismos regulatórios dos LncRNAs nos níveis transcricionais e pós-transcricionais. Este estudo pode fornecer informações úteis sobre os LncRNAs como alvos terapêuticos ou biomarcadores para o tratamento da aterosclerose.

Abstract Atherosclerosis is the most common cause of cardiovascular disease globally, associated with a high incidence of clinical events. Accumulating evidence has elucidated that long non-coding RNAs (lncRNAs) as a novel class of transcripts with critical roles in the pathophysiological processes of atherosclerosis. In this review, we summarize the recent progress of lncRNAs in the development of atherosclerosis. We mainly describe the diverse regulatory mechanisms of lncRNAs at the transcriptional and post-transcriptional levels. This study may provide helpful insights about lncRNAs as therapeutic targets or biomarkers for atherosclerosis treatment.

Selectivity of herbicides applied to Brazilian tree species at post-emergence

The presence of weeds in silvicultural systems has been considered one of the main obstacles to the success of projects designed to recover degraded areas. The aim of this study was to evaluate the selectivity of herbicides applied at post-emergence in the initial growth of seedlings of capixingui (Croton floribundus), açoita-cavalo (Luehea divaricata), and guaritá (Astronium graveolens), in the municipalities of Jaboticabal and Junqueirópolis, state of São Paulo. The experimental design was completely randomized, with four replications, and the treatments consisted of herbicides (g a.i.·ha-1) clethodim + phenoxaprop-p-ethyl (50 + 50), sethoxydim (184), quizalofop-p-ethyl (75), nicosulfuron (50), fluazifop-p-butyl (125), fomesafen (225), haloxyfop-methyl (48), bentazon (720), chlorimuron-ethyl (15), in addition to control without herbicide. The characteristics analyzed were: plant height increase and visual phytointoxication at 7, 14, 21, 28, 35, and 42 days after herbicide application. At the end of the experiment, the shoots of the plants were removed to assess shoot dry matter. The herbicides clethodim + fenoxaprop-p-ethyl, fluazifop-p-butyl, and quizalofop-p-ethyl showed selective potential for the species capixingui, açoita-cavalo, and guaritá. The herbicide chlorimuron-ethyl caused mild intoxication symptoms when applied to seedlings of capixingui and açoita-cavalo; also, it was not selective for the guaritá species grown in Jaboticabal. All species showed selectivity to the herbicides sethoxydim, fomesafen, haloxyfop-methyl, and nicosulfuron, as their growth and initial development were not influenced. The herbicide bentazon caused high percentages of injury to açoita-cavalo plants in both cultivation places, but it did not influence the growth and development of the species.

Necrodes littoralis (Coleoptera: Silphidae) visiting and breeding on a carcass in Italy

@#The community that progressively colonizes a decaying corpse can be considered a small ecosystem mostly composed of sarcosaprophagous arthropods belonging to the orders Diptera and Coleoptera. Studies on these species are often performed through animal models to obtain data on their succession, behaviour and life cycle, together with information on habitat, corpse conditions, season and association with other species. These data may be relevant for forensic investigations, especially concerning the estimation of Post Mortem Interval (PMI). An investigation on the sarcosaprophagous insect community in a rural area was set in Calabria (Southern Italy), using a pig, Sus scrofa Linnaeus, 1758 (Artiodactyla: Suidae) as experimental model. Analyses of the community of Diptera and Coleoptera revealed the massive presence of Necrodes littoralis (Linnaeus, 1758) (Coleoptera: Silphidae). Adults of this species reached the carcass during the bloated stage and a large amount of larvae was detected from the decay stage onwards, simultaneous to the sharp decrease in dipteran larvae and pupae. The occurrence and the activity of N. littoralis should be considered to avoid misinterpretation and errors in estimating PMI in forensic investigation.

Opportunities and Challenges of RNA Interference Therapeutics in Oncology / 中国肺癌杂志

As the discovery of RNA interference (RNAi) and the gradual conquering of a series of technical issues, a few of RNAi therapeutics have been approved in the non-tumor field abroad. With the advantages of high specificity, long duration of efficacy, and high success rate of development, RNAi therapeutics have become the emerging field globally. There are no RNAi therapeutics approved in oncology so far, and people are hoping a breakthrough in the field. In the present article, the characteristics and potential anti-tumor mechanism of RNAi therapeutics, difficulties in delivery system and progress in oncology are described, and the potential reasons why their success in non-tumor field is difficult to be simply replicated in tumor field are analyzed, providing reference for research and clinical transformation of RNAi therapeutics in oncology.
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Inhibitory Effect of Interference with PD-L1 Expression on B-cell lymphoma in Mice / 中国实验血液学杂志

OBJECTIVE@#To investigate the potential inhibitory effect of interference with PD-L1 on B cell lymphoma in mice.@*METHODS@#Three shRNA vectors for mouse CD274 (PD-L1) were constructed and transiently transfected into 293T cells. RT-qPCR was used to validate the interference efficiency of CD274. The shRNA vector that interfere efficiently with CD274 expression was packaged by using lentivirus packaging system to generate shRNA lentivirus, and then transfected into A20 lymphoma cell line. The methyl thiazol terazolium (MTT) assay was used to detect proliferation after 48 h culture of CD274-sh A20 cells. Meanwhile, BALB/c mice were hypodermically infected with CD274-sh A20 cells. Infected mice were observed daily and assessed to visualize tumor by in vivo fluorescence imaging.@*RESULTS@#The proliferation rate of CD274-sh A20 cells in vitro was significantly lower than that of A20 cells (P<0.05). The tumor size detected by in vivo fluorescence imaging showed a significant reduce in tumor bearing mice with CD274-sh compared with other tumor bearing mice. And the weight and size of tumor in CD274-sh group were also significantly reduced compared with other group (P<0.05). Moreover, the survival time of tumor bearing mice in CD274-sh group was longer than that of the PD-L1 high expression group.@*CONCLUSION@#PD-L1 plays an important role in the incidence and the progression of lymphoma, and the shRNA-based PD-L1 knockdown can inhibit cell proliferation of A20 cells and partly suppress tumor growth.

Analysis of the development trend of small nucleic acid drugs / 中国药房

OBJECTIVE To know about the development trend of small nucleic acid drugs in the world ，to provide reference for the research and development of small nucleic acid drug in China. METHODS By searching the academic literature and patents related to small nucleic acid drugs through the Web of Science literature database and PatSnap patent database from Jan. 1980 to Dec. 2021，research and development situation of small nucleic acid drugs were revealed comprehensively by analyzing research enthusiasm，R&D countries ，R&D institutions and technical topics of small nucleic acid drugs. RESULTS & CONCLUSIONS A total of 59 819 documents and 37 645 patent groups were included. The global trend of small nucleic acid drug literature publication and patent application could be divided into three stages. From 2003 to 2021，the research enthusiasm for small nucleic acid drugs continued to increase. The United States ，China，Japan and Germany were the main research and development countries for small nucleic acid drugs. The number of document publications （25 703，15 927 papers）and patent applications （14 240、8 937 groups） in the United States and China were ahead of other countries ，and the research and development activities were relatively strong. Moreover，the number of document publications and patent applications in China in this field had grown rapidly in recent years. The R&D institution with the largest number of publications was the University of California （2 499 papers），the R&D institution with the largest number of patent applications was the American Ionis Corporation （1 378 groups），and the Chinese Academy of Sciences （1 580 papers）had been shortlisted among the top 10 document producing institutions in the world. However ，our country ’s research and development in this field are mostly based on basic research ，and the research on industrial application is slightly insufficient. The research focus in the field of small nucleic acid drugs mainly focuses on nucleic acid sequences and their modification and improvement and drug loading technology. RNA interference technology has gradually become a hot technology for small nucleic acid drugs.

Hippocampus is involved in 17β-estradiol exacerbating experimental occlusal inter- ference-induced chronic masseter hyperalgesia in ovariectomized rats / 北京大学学报(医学版)

OBJECTIVE@#To investigate the influence of chronic masseter hyperalgesia induced by 17β-estradiol (E2) and experimental occlusal interference (EOI) on underlying mechanism in hippocampus of ovariectomized (OVX) rats.@*METHODS@#In the study, 32 OVX rats were randomly divided into 4 groups (8 rats/group): The control group was OVX group, and 0 μg/d E2 (vehicle) injection was started 7 d after OVX without EOI; in the experimental group (1) OVX + E2 group, 80 μg/d E2 injection was started 7 d after OVX without EOI; in the experimental group (2) OVX + EOI group, vehicle injection was started 7 d after OVX and EOI was applied 17 d after OVX; in the experimental group (3) OVX + E2 + EOI group, 80 μg/d E2 injection was started 7 d after OVX and EOI was applied 17 d after OVX. Bilateral masseter muscle mechanical withdrawal thresholds were measured before OVX, 7 days after OVX (before E2 injection), 17 days after OVX (10 days after E2 injection and before EOI) and 24 days after OVX (7 days after EOI). Immunofluorescence staining was used to reveal phospho-extracellular signal regulated kinase 1/2 (p-ERK1/2)-positive neurons in CA3 of hippocampus. The protein expression of p-ERK1/2 in hippocampus was detected using Western Blot.@*RESULTS@#Compared with the control group [left side: (135.3±8.5) g, right side: (135.4±10.8) g], bilateral masseter muscle mechanical withdrawal thresholds of OVX+E2 group [left side: (113.3±5.6) g, right side: (112.5 ± 5.6) g] and OVX+EOI group [left side: (93.3±5.4) g, right side: 90.8±5.5) g] were decreased (P < 0.01). Bilateral masseter muscle mechanical withdrawal thresholds were significantly lower in OVX+E2+EOI group [left side: (81.2±6.2) g, right side: 79.8±7.7) g] than in the control, OVX+E2 and OVX+EOI groups (P < 0.05). The proportion of p-ERK1/2 positive neurons in the CA3 region of the hippocampus was increased in the control, OVX+E2, OVX+EOI and OVX+E2+EOI groups in turn, and the difference between the groups was statistically significant (P < 0.05). p-ERK1/2 protein expression was increased in the control, OVX+E2 and OVX+EOI groups in turn, but the difference was not statistically significant (P>0.05). p-ERK1/2 expression was significantly higher in OVX+E2+EOI group than in the other three groups (P < 0.05).@*CONCLUSION@#High concentration of E2 could exacerbated EOI-induced chronic masseter hyperalgesia in ovariectomized rats, and its central mechanism may be related to the upregulation of the phosphorylation of ERK1/2 in hippocampus.

In vitro effect of a short hairpin RNA targeting epidermal growth factor receptor combined with sirolimus on proliferation and apoptosis of the human cutaneous squamous cell carcinoma cell line Colo-16 / 中华皮肤科杂志

Objective:To investigate the effect of a short hairpin RNA (shRNA) targeting epidermal growth factor receptor (EGFR) combined with sirolimus on proliferation and apoptosis of the human cutaneous squamous cell carcinoma cell line Colo-16, and to explore underlying mechanisms.Methods:Cultured Colo-16 cells were divided into 5 groups: normal cell group receiving conventional culture and treatment with phosphate-buffered saline (PBS) , negative control group transfected with a shRNA-NC-expressing plasmid and treated with PBS, sirolimus group receiving conventional culture and sirolimus treatment, EGFR shRNA group transfected with an EGFR shRNA-expressing plasmid and treated with PBS, and combined group transfected with an EGFR shRNA-expressing plasmid and treated with sirolimus. Methyl thiazol tetrazolium (MTT) assay was performed to evaluate cellular proliferative activity in the above groups from 24 to 96 hours, and flow cytometry to detect cell apoptosis after 48-hour treatment. Semiquantitative RT-PCR was conducted to determine the mRNA expression of Bcl-2 and Bax, and Western blot analysis to determine the expression of apoptosis-related proteins cleaved caspase-3, cleaved caspase-9, Bcl-2, Bax, cell proliferation-related proteins phosphorylated mammalian target of rapamycin (p-mTOR) , phosphorylated protein kinase B (p-AKT) , phosphorylated 70-kDa ribosomal protein S6 kinase (p-P70S6k) , and cyclin D1. Comparisons among groups were carried out by using one-way analysis of variance, and multiple comparisons between 2 groups by using Student-Newman-Keuls q test. Results:MTT assay showed that the proliferative activity of Colo-16 cells was significantly lower in the sirolimus group, EGFR shRNA group and combined group during 24 - 96 hours than in the normal cell group (all P < 0.05) , and higher in the combined group than in the sirolimus group and EGFR shRNA group at 24-96 hours (all P < 0.001) , and there was no significant difference in the cellular proliferative activity at any time points between the normal cell group and negative control group (all P > 0.05) . Flow cytometry showed that the apoptosis rate was significantly higher in the sirolimus group, EGFR shRNA group and combined group (9.52% ± 0.25%, 12.65% ± 0.23%, 19.81% ± 0.31%, respectively) than in the normal cell group (3.33% ± 0.18%, q = 60.07, 78.08, 122.81, respectively, all P < 0.001) and negative control group (3.42% ± 0.19%, q = 59.90, 77.91, 122.64, respectively, all P < 0.001) , and was highest in the combined group. As RT-PCR and Western blot analysis revealed, the sirolimus group, EGFR shRNA group and combined group showed significantly decreased mRNA expression of Bcl-2 and protein expression of cyclin D1, p-AKT, p-mTOR, p-P70S6K and Bcl-2, but significantly increased mRNA expression of Bax and protein expression of cleaved caspase-3, cleaved caspase-9 and Bax compared with the normal cell group (all P < 0.05) . Compared with the sirolimus group and EGFR shRNA group, the combined group showed significantly decreased mRNA expression of Bcl-2 and protein expression of cyclin D1, p-AKT, p-mTOR, p-P70S6K and Bcl-2 (all P < 0.05) , but significantly increased mRNA expression of Bax and protein expression of cleaved caspase-3, cleaved caspase-9 and Bax (all P < 0.01) . Conclusion:EGFR shRNA and sirolimus exerted a synergistic effect in inhibiting the proliferation and promoting the apoptosis of Colo-16 cells, which may be related to the inhibition of the phosphoinositide 3-kinase (PI3K) /AKT/mTOR pathway.

Autophagy enhanced by curcumin ameliorates inflammation in atherogenesis via the TFEB-P300-BRD4 axis

Disturbance of macrophage-associated lipid metabolism plays a key role in atherosclerosis. Crosstalk between autophagy deficiency and inflammation response in foam cells (FCs) through epigenetic regulation is still poorly understood. Here, we demonstrate that in macrophages, oxidized low-density lipoprotein (ox-LDL) leads to abnormal crosstalk between autophagy and inflammation, thereby causing aberrant lipid metabolism mediated through a dysfunctional transcription factor EB (TFEB)-P300-bromodomain-containing protein 4 (BRD4) axis. ox-LDL led to macrophage autophagy deficiency along with TFEB cytoplasmic accumulation and increased reactive oxygen species generation. This activated P300 promoted BRD4 binding on the promoter regions of inflammatory genes, consequently contributing to inflammation with atherogenesis. Particularly, ox-LDL activated BRD4-dependent super-enhancer associated with liquid-liquid phase separation (LLPS) on the regulatory regions of inflammatory genes. Curcumin (Cur) prominently restored FCs autophagy by promoting TFEB nuclear translocation, optimizing lipid catabolism, and reducing inflammation. The consequences of P300 and BRD4 on super-enhancer formation and inflammatory response in FCs could be prevented by Cur. Furthermore, the anti-atherogenesis effect of Cur was inhibited by macrophage-specific Brd4 overexpression or Tfeb knock-out in Apoe knock-out mice via bone marrow transplantation. The findings identify a novel TFEB-P300-BRD4 axis and establish a new epigenetic paradigm by which Cur regulates autophagy, inhibits inflammation, and decreases lipid content.

Chemical screen identifies shikonin as a broad DNA damage response inhibitor that enhances chemotherapy through inhibiting ATM and ATR

DNA damage response (DDR) is a highly conserved genome surveillance mechanism that preserves cell viability in the presence of chemotherapeutic drugs. Hence, small molecules that inhibit DDR are expected to enhance the anti-cancer effect of chemotherapy. Through a recent chemical library screen, we identified shikonin as an inhibitor that strongly suppressed DDR activated by various chemotherapeutic drugs in cancer cell lines derived from different origins. Mechanistically, shikonin inhibited the activation of ataxia telangiectasia mutated (ATM), and to a lesser degree ATM and RAD3-related (ATR), two master upstream regulators of the DDR signal, through inducing degradation of ATM and ATR-interacting protein (ATRIP), an obligate associating protein of ATR, respectively. As a result of DDR inhibition, shikonin enhanced the anti-cancer effect of chemotherapeutic drugs in both cell cultures and in mouse models. While degradation of ATRIP is proteasome dependent, that of ATM depends on caspase- and lysosome-, but not proteasome. Overexpression of ATM significantly mitigated DDR inhibition and cell death induced by shikonin and chemotherapeutic drugs. These novel findings reveal shikonin as a pan DDR inhibitor and identify ATM as a primary factor in determining the chemo sensitizing effect of shikonin. Our data may facilitate the development of shikonin and its derivatives as potential chemotherapy sensitizers through inducing ATM degradation.

Mitochondrial complex I as a therapeutic target for Alzheimer's disease

Alzheimer's disease (AD), the most prominent form of dementia in the elderly, has no cure. Strategies focused on the reduction of amyloid beta or hyperphosphorylated Tau protein have largely failed in clinical trials. Novel therapeutic targets and strategies are urgently needed. Emerging data suggest that in response to environmental stress, mitochondria initiate an integrated stress response (ISR) shown to be beneficial for healthy aging and neuroprotection. Here, we review data that implicate mitochondrial electron transport complexes involved in oxidative phosphorylation as a hub for small molecule-targeted therapeutics that could induce beneficial mitochondrial ISR. Specifically, partial inhibition of mitochondrial complex I has been exploited as a novel strategy for multiple human conditions, including AD, with several small molecules being tested in clinical trials. We discuss current understanding of the molecular mechanisms involved in this counterintuitive approach. Since this strategy has also been shown to enhance health and life span, the development of safe and efficacious complex I inhibitors could promote healthy aging, delaying the onset of age-related neurodegenerative diseases.

Pulmonary delivery of siRNA against acute lung injury/acute respiratory distress syndrome

The use of small interfering RNAs (siRNAs) has been under investigation for the treatment of several unmet medical needs, including acute lung injury/acute respiratory distress syndrome (ALI/ARDS) wherein siRNA may be implemented to modify the expression of pro-inflammatory cytokines and chemokines at the mRNA level. The properties such as clear anatomy, accessibility, and relatively low enzyme activity make the lung a good target for local siRNA therapy. However, the translation of siRNA is restricted by the inefficient delivery of siRNA therapeutics to the target cells due to the properties of naked siRNA. Thus, this review will focus on the various delivery systems that can be used and the different barriers that need to be surmounted for the development of stable inhalable siRNA formulations for human use before siRNA therapeutics for ALI/ARDS become available in the clinic.

Effect of polycystin2 on differentiation and maturation of osteoblasts promoted by low-frequency pulsed electromagnetic fields / 生物工程学报

It is known that low-frequency pulsed electromagnetic fields (PEMFs) can promote the differentiation and maturation of rat calvarial osteoblasts (ROBs) cultured in vitro. However, the mechanism that how ROBs perceive the physical signals of PEMFs and initiate osteogenic differentiation remains unknown. In this study, we investigated the relationship between the promotion of osteogenic differentiation of ROBs by 0.6 mT 50 Hz PEMFs and the presence of polycystin2 (PC2) located on the primary cilia on the surface of ROBs. First, immunofluorescence staining was used to study whether PC2 is located in the primary cilia of ROBs, and then the changes of PC2 protein expression in ROBs upon treatment with PEMFs for different time were detected by Western blotting. Subsequently, we detected the expression of PC2 protein by Western blotting and the effect of PEMFs on the activity of alkaline phosphatase (ALP), as well as the expression of Runx-2, Bmp-2, Col-1 and Osx proteins and genes related to bone formation after pretreating ROBs with amiloride HCl (AMI), a PC2 blocker. Moreover, we detected the expression of genes related to bone formation after inhibiting the expression of PC2 in ROBs using RNA interference. The results showed that PC2 was localized on the primary cilia of ROBs, and PEMFs treatment increased the expression of PC2 protein. When PC2 was blocked by AMI, PEMFs could no longer increase PC2 protein expression and ALP activity, and the promotion effect of PEMFs on osteogenic related protein and gene expression was also offset. After inhibiting the expression of PC2 using RNA interference, PEMFs can no longer increase the expression of genes related to bone formation. The results showed that PC2, located on the surface of primary cilia of osteoblasts, plays an indispensable role in perceiving and transmitting the physical signals from PEMFs, and the promotion of osteogenic differentiation of ROBs by PEMFs depends on the existence of PC2. This study may help to elucidate the mechanism underlying the promotion of bone formation and osteoporosis treatment in low-frequency PEMFs.

Construction of EF-G knockdown strain of Mycobacterium smegmatis and drug resistance analysis / 生物工程学报

As the only translational factor that plays a critical role in two translational processes (elongation and ribosome regeneration), GTPase elongation factor G (EF-G) is a potential target for antimicrobial agents. Both Mycobacterium smegmatis and Mycobacterium tuberculosis have two EF-G homologous coding genes, MsmEFG1 (MSMEG_1400) and MsmEFG2 (MSMEG_6535), fusA1 (Rv0684) and fusA2 (Rv0120c), respectively. MsmEFG1 (MSMEG_1400) and fusA1 (Rv0684) were identified as essential genes for bacterial growth by gene mutation library and bioinformatic analysis. To investigate the biological function and characteristics of EF-G in mycobacterium, two induced EF-G knockdown strains (Msm-ΔEFG1(KD) and Msm-ΔEFG2(KD)) from Mycobacterium smegmatis were constructed by clustered regularly interspaced short palindromic repeats interference (CRISPRi) technique. EF-G2 knockdown had no effect on bacterial growth, while EF-G1 knockdown significantly retarded the growth of mycobacterium, weakened the film-forming ability, changed the colony morphology, and increased the length of mycobacterium. It was speculated that EF-G might be involved in the division of bacteria. Minimal inhibitory concentration assay showed that inhibition of EF-G1 expression enhanced the sensitivity of mycobacterium to rifampicin, isoniazid, erythromycin, fucidic acid, capreomycin and other antibacterial agents, suggesting that EF-G1 might be a potential target for screening anti-tuberculosis drugs in the future.

Incerteza de medição associada à contagem microbiana de produtos farmacêuticos / Measurement uncertainty associated with microbial count of pharmaceutical products

A contaminação microbiana pode comprometer a eficácia e a segurança dos produtos farmacêuticos. Os testes de contagem microbiana são utilizados para avaliar a qualidade microbiológica de produtos farmacêuticos não estéreis, exigidos pela maioria dos compêndios farmacopeicos. Apesar disso, raramente é considerada a avaliação da incerteza de medição para testes de contagem microbiana, o que pode levar a falsas decisões quanto à conformidade/nãoconformidade. Neste trabalho avaliamos os efeitos de matriz nos testes de contagem microbiana e sua avaliação de incerteza top-down, e avaliamos a incerteza da medição utilizando a abordagem bottom-up, além de que estimamos os riscos do consumidor ou do produtor devido à incerteza da medição. As incertezas combinada e expandida são calculadas empregando-se a abordagem topdown consideraram a exatidão (recuperação) e a precisão como os principais componentes de incerteza. O componente de incerteza da exatidão foi o mais relevante em 59% das amostras estudadas, enquanto a precisão foi a principal fonte de incerteza em apenas 41% das amostras, sendo observado que quanto maior a interferência da matriz, maior o fator de incerteza e, consequentemente, maior a assimetria para o intervalo em torno da medida. A partir da abordagem bottom-up, foram identificadas e quantificadas três principais fontes de incerteza: fator de diluição, volume plaqueado e contagem das placas. A contribuição dessas fontes de incerteza depende do valor medido da carga microbiana em produtos farmacêuticos, a contribuição do fator de diluição e das incertezas do volume plaqueado aumentam com o aumento do valor medido, enquanto a contribuição da contagem das placas diminui com o aumento do valor medido. Foi possível avaliar o risco de decisões falsas devido à incerteza de medição, por meio das estimativas dos riscos do consumidor ou do produtor. Os riscos foram avaliados utilizando-se o método Monte Carlo. Portanto, foi demonstrado a relevância da avaliação da incerteza de medição para garantir a confiabilidade dos resultados dos testes de contagem microbiana e a apoiar a tomada de decisões quando a avaliação da conformidade/não-conformidade dos produtos farmacêuticos não estéreis

Microbial contamination can compromise the efficacy and safety of pharmaceutical products. Microbial counting tests are used to assess the microbiological quality of non-sterile pharmaceutical products required by most pharmacopoeia compendiums. Despite this, measurement uncertainty assessment for microbial count tests is rarely considered, which can lead to false compliance/non-compliance decisions. In this work we evaluated the matrix effects on microbial counting tests and their top-down uncertainty assessment, and evaluated measurement uncertainty using the bottom-up approach, inaddition to estimating the consumer's or producer's risks due to measurement uncertainty. The combined and expanded uncertainties calculated using the top-down approach considered accuracy (recovery) and accuracy as the main components of uncertainty. The uncertainty component of accuracy was the most relevant in 59% of the samples studied, while accuracy was the main source of uncertainty in only 41% of the samples, being observed that the greater the interference of the matrix, the greater the uncertainty factor and, consequently, the greater the asymmetry for the interval around the measurement. From the bottom-up approach, three main sources of uncertainty were identified and quantified: dilution factor, platelet volume and plaque count. The contribution of these sources of uncertainty depends on the measured value of microbial load in pharmaceutical products, the contribution of the dilution factor and uncertainties of the plated volume increase with the increase in the measured value, while the contribution of plate counting decreases with the increase of the measured value. It was possible to assess the risk of false decisions due to measurement uncertainty by estimating consumer or producer risks. The risks were evaluated using the Monte Carlo method. Therefore, the relevance of measuring uncertainty assessment has been demonstrated to ensure the reliability of microbial count test results and to support decision-making when assessing non-sterile pharmaceutical conformity/non-compliance

Fundamentos moleculares de la exclusión competitiva durante la coinfección de virus respiratorios: a propósito del COVID-19 / Molecular foundations of competitive exclusion during coinfection of respiratory viruses: about COVID-19

Introducción: La idea de exclusión competitiva es indiscutible cuando se trata de animales y bacterias que intentan ocupar el mismo nicho ecológico, pero su aplicación a la coinfección viral no es tan sencilla de interpretar. La interferencia viral es un fenómeno en el que un virus suprime competitivamente la replicación de otros virus coinfectantes y es el resultado más común de las coinfecciones virales. Objetivo: Comprender mejor el comportamiento de las infecciones respiratorias concomitantes en escenarios de brotes comunitarios y de forma individual en entornos hospitalarios e individuos con comorbilidades. Métodos: Se realizó una búsqueda de información en las bases de datos MEDLINE / PubMed, SciELO y LILACS. También se consideraron artículos publicados en el repositorio de preimpresión medRxiv y los informes de los Centros para el Control y Prevención de enfermedades de los Estados Unidos de América. Mediante el gestor de referencias Mendeley, se eliminaron los duplicados y aquellos que no se ajustaban al objetivo del estudio, seleccionando 48 artículos para la revisión. Análisis y síntesis de la in formación: En la literatura científica se encontró evidencia que sustenta la exclusión competitiva viral entre virus relacionados que comparten células susceptibles y permisivas. Conclusión: La exclusión competitiva impide que dos virus que comparten rutas de transmisión similares y el mismo órgano diana, infecten no sólo al mismo tiempo, sino que también se propaguen con éxito. Por lo tanto, la sindemia producida por virus que comparten estas características podría ser un evento improbable(AU)

Introduction: The idea of competitive exclusion is undisputed when it comes to animals and bacteria trying to occupy the same ecological niche, but its application to viral coinfection is not so simple to interpret. Viral interference is a phenomenon in which one virus competitively suppresses the replication of other co-infecting viruses and is the most common outcome of viral co-infections. Objective: To better understand the behavior of concomitant respiratory infections in community outbreak settings and individually in hospital settings and individuals with comorbidities. Methods: A search for information was performed in the MEDLINE / PubMed, SciELO and LILACS databases. Articles published in the preprint repository medRxiv and reports from the US Centers for Disease Control and Prevention were also considered. Using the Mendeley reference manager, duplicates and those that did not fit the study objective were eliminated, selecting 48 articles for the review. Analysis and synthesis of information: Evidence supporting viral competitive exclusion between related viruses sharing susceptible and permissive cells was found in the scientific literature. Conclusion: Competitive exclusion prevents two viruses that share similar transmission routes and the same target organ from infecting not only at the same time, but also from spreading successfully. Therefore, syndemia produced by viruses sharing these characteristics could be an unlikely event(AU)

Construction of a curcumin-siRNA co-delivery system based on mesoporous silica and its effect on M2-type polarization of macrophages / 口腔疾病防治

Objective @#To fabricate a co-delivery system of curcumin (CUR) and siRNA based on mesoporous silica nanoparticles (MSN) and investigate its potential application in inducing macrophage M2 polarization.@*Methods@# MSNs were synthesized using the conventional sol-gel method. The interior mesochannels were occupied by small-molecule CUR, while the exterior surface was adsorbed by cationic polymeric polyethyleneimine (PEI) to link the negatively charged siRNA molecules to formulate the (CUR@MSN)PEI/siRNA co-delivery system. The formulation process was monitored by transmission electron microscopy(TEM). The MTT assay was used to evaluate the cytotoxicity in RAW264.7 cells under various concentrations of nanoparticles. Confocal laser scanning microscopy and TEM were used to observe cell internalization using FAM-labeled siRNA. GAPDH-targeting siRNA was used to prepare nanoparticles and then was transfected into RAW264.7 cells to observe the silencing efficiency of target genes. The knockdown efficiency was examined by real-time quantitative PCR. The related control groups were untreated cells, CUR delivery only and the co-delivery of CUR and siRNA negative control. By loading miRNA-130a-3p antisense oligonucleotide (ASO) to transfect RAW264.7 cells, the effects on the polarization of macrophages were observed. The M2 polarization marker arginase 1 (Arg-1) was measured by western blotting. The related control groups were untreated cells, CUR delivery only and co-delivery of CUR and miRNA negative control. @* Results @# The (CUR@MSN)PEI/siRNA co-delivery system was successfully formulated. The nanoparticles exhibited dose-dependent cytotoxicity, and the cell viability was maintained over 90% when the nanoparticle concentration was less than 10 μg/mL. A high cell uptake efficiency was observed, and the target gene knockdown efficiency was greater than 80% (P < 0.05 vs. all the other groups). The CUR delivery-only group and co-delivery of the CUR-and miRNA-negative control group improved Arg-1 expression ~ 3-fold (P < 0.05 vs. untreated cells). Using the co-delivery of CUR and ASO, synergistic effects were obtained, and Arg-1 expression was increased ~ 8-fold (P < 0.05 vs. all the other groups).@*Conclusion @#The CUR-siRNA co-delivery system can effectively transfect macrophages and synergistically induce M2 polarization.

Effects of siRNA interference with Nrf2 on the regulation of glutathione S-transferase and IL-1β in A549 cells exposed to hyperoxia / 中国新生儿科杂志

Objective:To study the gene expression of nuclear factor erythroid-2-related factor 2 (Nrf2), glutathione-S-transferase (GST) and interleukin-1 β (IL-1β) in A549 cells exposed to hyperoxia and cell apoptosis after siRNA interference with Nrf2.Method:Normal A549 cell lines were assigned into normoxia+siRNA group, normoxia+control group, hyperoxia+siRNA group and hyperoxia+control group according to whether siRNA interference was used and the exposure environment (normoxia/hyperoxia). The hyperoxia environment contained 95%O 2 and 5%CO 2. The levels of mRNA expression of Nrf2, GST and IL-1β were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Flow cytometry was used to examine cell apoptosis of the hyperoxia+control group and hyperoxia+siRNA group at different time points. Analysis of variance (ANOVA) was used to test the relative gene expression and apoptosis of A549 cells. Result:(1) Compared with the normoxia+control group, the expression of Nrf2 and GST in the hyperoxia+control group was significantly increased ( P<0.05), and the expression of IL-1β was significantly decreased ( P<0.05); the expression of Nrf2 and GST in the normoxia+siRNA group decreased significantly ( P<0.05), while the expression of IL-1β increased significantly ( P<0.05). (2) Compared with the normoxia+siRNA group, Nrf2 expression in the hyperoxia+siRNA group showed no significant changes ( P=0.230), GST expression increased slightly ( P=0.057), and IL-1β expression decreased slightly ( P=0.112). (3) Compared with the hyperoxia+control group, the expression of Nrf2 and GST in the hyperoxia+siRNA group decreased significantly ( P<0.05), and the expression of IL-1β increased significantly ( P=0.042). (4) Compared with the hyperoxia+control group, the apoptosis of A549 cells in the hyperoxia+siRNA group increased significantly at 24 h, 48 h and 72 h ( P<0.05). Conclusion:After interfering with Nrf2, siRNA may regulate the expression of GST and IL-1β, preventing oxidative stress, reducing inflammatory response and inhibiting apoptosis.

Molecular cloning and characterization of a novel aspartyl aminopeptidase from Trichinella spiralis

@#Trichinellosis is an important zoonotic parasitic disease worldwide and is principally caused by ingesting animal meat containing Trichinella infective larvae. Aspartyl aminopeptidase is an intracytoplasmic metalloproteinase that specifically hydrolyzes the N-terminus of polypeptides free of acidic amino acids (aspartic acid and glutamate), and plays an important role in the metabolism, growth and development of organisms. In this study, a novel T. spiralis aspartyl aminopeptidase (TsAAP) was cloned and expressed, and its biological properties and roles in worm growth and development were investigated. The results revealed that TsAAP transcription and expression in diverse T. spiralis stages were detected by RT-PCR and Western blotting, and primarily localized at cuticle, stichosome and intrauterine embryos of this nematode by immunofluorescence test. rTsAAP has the enzymatic activity of native AAP to hydrolyze the substrate H-Glu-pNA. There was a specific binding between rTsAAP and murine erythrocyte, and the binding site was localized in erythrocyte membrane proteins. Silencing of TsAAP gene by specific dsRNA significantly reduced the TsAAP expression, enzymatic activity, intestinal worm burdens and female fecundity. The results demonstrated that TsAAP participates in the growth, development and fecundity of T. spiralis and it might be a potential target molecule for anti-Trichinella vaccines.