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1.
Commun Biol ; 6(1): 387, 2023 04 08.
Article in English | MEDLINE | ID: mdl-37031303

ABSTRACT

SARS-CoV-2 receptor binding domains (RBDs) interact with both the ACE2 receptor and heparan sulfate on the surface of host cells to enhance SARS-CoV-2 infection. We show that suramin, a polysulfated synthetic drug, binds to the ACE2 receptor and heparan sulfate binding sites on the RBDs of wild-type, Delta, and Omicron variants. Specifically, heparan sulfate and suramin had enhanced preferential binding for Omicron RBD, and suramin is most potent against the live SARS-CoV-2 Omicron variant (B.1.1.529) when compared to wild type and Delta (B.1.617.2) variants in vitro. These results suggest that inhibition of live virus infection occurs through dual SARS-CoV-2 targets of S-protein binding and previously reported RNA-dependent RNA polymerase inhibition and offers the possibility for this and other polysulfated molecules to be used as potential therapeutic and prophylactic options against COVID-19.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Suramin/pharmacology , Angiotensin-Converting Enzyme 2 , Spike Glycoprotein, Coronavirus , Heparitin Sulfate
2.
Biotechnol Prog ; 38(6): e3286, 2022 11.
Article in English | MEDLINE | ID: mdl-35808852

ABSTRACT

In this manuscript, we employ parallel batch stability and chromatographic screens in concert with linear and step gradient experiments to develop a high yield, HCP clearance anion exchange capture process for lentiviral vector (LVV) purification. An initial broad resin screen is carried out to determine anion exchange-based resins that exhibit high recovery of LVV. LVV stability is then evaluated and conditions are established where the vector exhibits good stability, namely phosphate buffer at pH 6.5-7.5, with low to moderate salt concentrations. A subsequent high-throughput batch screen is then carried out with a subset of resins selected from the first screen under stable conditions to identify optimal wash and elution steps to further improve product yield and protein clearance. Linear gradient experiments are also conducted in mini-column format to refine the operating conditions and final step gradient processes are established that exhibit greater than 70% yield of infectious LVV while also achieving up to 2.89 log reduction values (LRV) of HCPs during the process. The large set of stability and chromatographic data provided in this work represent an important contribution to knowledge in the field about the chromatographic efficacy of a wide range of resins for LVV bioprocessing under stable conditions.


Subject(s)
Anion Exchange Resins , Proteins , Chromatography, Ion Exchange/methods , Ion Exchange , Sodium Chloride
3.
Biotechnol Bioeng ; 119(10): 2842-2856, 2022 10.
Article in English | MEDLINE | ID: mdl-35822281

ABSTRACT

Circadian rhythms are characterized as oscillations that fluctuate based on a 24 h cycle and are responsible for regulation of physiological functions. While the internal clock synchronizes gene expression using external cues like light, a similar synchronization can be induced in vitro by incubating the cells with an increased percentage of serum followed by its rapid removal. Previous studies have suggested that synchronization of HepG2 cell line induced the rhythmic expression of drug-metabolizing enzymes (DME) most specifically the cytochrome P450 enzymes. However, there is a lack of evidence demonstrating the influence of three-dimensional microenvironment on the rhythmicity of these genes. To understand this interplay, gene expression of the circadian machinery and CYP450s were compared using the model human hepatocarcinoma cell line, HepG2. Upon serum shock synchronization, gene and protein expression of core clock regulators was assessed and rhythmic expression of these genes was demonstrated. Further insight into the interrelations between various gene pairs was obtained using statistical analysis. Using RNA sequencing, an in-depth understanding of the widespread effects of circadian regulation on genes involved in metabolic processes in the liver was obtained. This study aids in the better understanding of chronopharmacokinetic events in humans using physiologically relevant 3D culture systems.


Subject(s)
Circadian Rhythm , Liver , Circadian Rhythm/genetics , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Gene Expression Regulation , Humans , Liver/metabolism , Sequence Analysis, RNA
4.
Pharmaceuticals (Basel) ; 15(2)2022 Feb 21.
Article in English | MEDLINE | ID: mdl-35215371

ABSTRACT

With the increased prevalence of new SARS-CoV-2 variants of concern, such as Delta and Omicron, the COVID-19 pandemic has become an ongoing human health disaster, killing millions worldwide. SARS-CoV-2 invades its host through the interaction of its spike (S) protein with a host cell receptor, angiotensin-converting enzyme 2 (ACE2). In addition, heparan sulfate (HS) on the surface of host cells plays an important role as a co-receptor for this viral pathogen-host cell interaction. Our previous studies demonstrated that many sulfated glycans, such as heparin, fucoidans, and rhamnan sulfate have anti-SARS-CoV-2 activities. In the current study, a small library of sulfated glycans and highly negatively charged compounds, including pentosan polysulfate (PPS), mucopolysaccharide polysulfate (MPS), sulfated lactobionic acid, sulodexide, and defibrotide, was assembled and evaluated for binding to the S-proteins and inhibition of viral infectivity in vitro. These compounds inhibited the interaction of the S-protein receptor-binding domain (RBD) (wild type and different variants) with immobilized heparin, a highly sulfated HS, as determined using surface plasmon resonance (SPR). PPS and MPS showed the strongest inhibition of interaction of heparin and S-protein RBD. The competitive binding studies showed that the IC50 of PPS and MPS against the S-protein RBD binding to immobilized heparin was ~35 nM and ~9 nM, respectively, much lower than the IC50 for soluble heparin (IC50 = 56 nM). Both PPS and MPS showed stronger inhibition than heparin on the S-protein RBD or spike pseudotyped lentiviral particles binding to immobilized heparin. Finally, in an in vitro cell-based assay, PPS and MPS exhibited strong antiviral activities against pseudotyped viral particles of SARS-CoV-2 containing wild-type or Delta S-proteins.

6.
Mar Drugs ; 19(12)2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34940684

ABSTRACT

The COVID-19 pandemic is a major human health concern. The pathogen responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), invades its host through the interaction of its spike (S) protein with a host cell receptor, angiotensin-converting enzyme 2 (ACE2). In addition to ACE2, heparan sulfate (HS) on the surface of host cells also plays a significant role as a co-receptor. Our previous studies demonstrated that sulfated glycans, such as heparin and fucoidans, show anti-COVID-19 activities. In the current study, rhamnan sulfate (RS), a polysaccharide with a rhamnose backbone from a green seaweed, Monostroma nitidum, was evaluated for binding to the S-protein from SARS-CoV-2 and inhibition of viral infectivity in vitro. The structural characteristics of RS were investigated by determining its monosaccharide composition and performing two-dimensional nuclear magnetic resonance. RS inhibition of the interaction of heparin, a highly sulfated HS, with the SARS-CoV-2 spike protein (from wild type and different mutant variants) was studied using surface plasmon resonance (SPR). In competitive binding studies, the IC50 of RS against the S-protein receptor binding domain (RBD) binding to immobilized heparin was 1.6 ng/mL, which is much lower than the IC50 for heparin (~750 ng/mL). RS showed stronger inhibition than heparin on the S-protein RBD or pseudoviral particles binding to immobilized heparin. Finally, in an in vitro cell-based assay, RS showed strong antiviral activities against wild type SARS-CoV-2 and the delta variant.


Subject(s)
Antiviral Agents/pharmacology , COVID-19 Drug Treatment , Deoxy Sugars/pharmacology , Mannans/pharmacology , Plant Extracts/pharmacology , SARS-CoV-2/drug effects , Seaweed , Antiviral Agents/therapeutic use , Aquatic Organisms , Deoxy Sugars/therapeutic use , Humans , Mannans/therapeutic use , Plant Extracts/therapeutic use , Protein Binding/drug effects , Spike Glycoprotein, Coronavirus/drug effects , Structure-Activity Relationship
7.
Front Psychol ; 12: 744921, 2021.
Article in English | MEDLINE | ID: mdl-35126228

ABSTRACT

BACKGROUND AND OBJECTIVES: Up to 10% of fathers experience perinatal depression, often accompanied by anxiety, with a detrimental impact on the emotional and behavioural development of infants. Yet, few evidence-based interventions specifically for paternal perinatal depression or anxiety exist, and few depressed or anxious fathers engage with support. This mini-review aims to build on the evidence base set by other recent systematic reviews by synthesising more recently available studies on interventions for paternal perinatal depression and anxiety. Secondarily, we also aimed to identify useful information on key implementation strategies, if any, that increase the engagement of men. METHODS: We drew upon three major previous systematic reviews and performed an updated search of PubMed/Medline; Psycinfo; Cochrane Database; Embase and Cinahl. The search was limited to trials, feasibility studies or pilot studies of interventions published between 2015 and 2020 that reported on fathers' perinatal mental health. We included psychological, educational, psychosocial, paternal, couple-focused, or group therapies, delivered face-to-face, via telephone and/or online that reported on either paternal depression, anxiety or both. RESULTS: Eleven studies satisfied search criteria (5 of which were not included in previous reviews). The majority were randomised controlled trials. Most interventions incorporated counselling, therapy or psychoeducation and took an indirect approach to perinatal mental health through antenatal or postnatal education and were couple-focused. No studies reported a presence of diagnosed depression or anxiety at baseline, although five studies reported a positive effect on sub-threshold symptoms. DISCUSSION: There was some evidence that these approaches may be useful in the initial engagement of fathers with perinatal supports and improve depression and anxiety scores. No studies targeted the explicit treatment of clinically depressed or anxious men, and this remains the most substantial gap in the peer-reviewed evidence base. Our results highlight the need to deliver perinatal interventions specifically designed for men and evaluate them in populations with clinical levels of depressive and anxious symptomatology.

8.
Biomacromolecules ; 21(8): 3081-3091, 2020 08 10.
Article in English | MEDLINE | ID: mdl-32573205

ABSTRACT

Tissue engineering and stem cell research greatly benefit from cell encapsulation within hydrogels as it promotes cell expansion and differentiation. Affinity-triggered hydrogels, an appealing solution for mild cell encapsulation, rely on selective interactions between the ligand and target and also on the multivalent presentation of these two components. Although these hydrogels represent a versatile option to generate dynamic, tunable, and highly functional materials, the design of hydrogel properties based on affinity and multivalency remains challenging and unstudied. Here, the avidin-biotin affinity pair, with the highest reported affinity constant, is used to address this challenge. It is demonstrated that the binding between the affinity hydrogel components is influenced by the multivalent display selected. In addition, the natural multivalency of the interaction must be obeyed to yield robust multicomponent synthetic protein hydrogels. The hydrogel's resistance to erosion depends on the right stoichiometric match between the hydrogel components. The developed affinity-triggered hydrogels are biocompatible and support encapsulation of induced pluripotent stem cells and their successful differentiation into a neural cell line. This principle can be generalized to other affinity pairs using multimeric proteins, yielding biomaterials with controlled performance.


Subject(s)
Cell Encapsulation , Hydrogels , Biocompatible Materials , Cell Differentiation , Tissue Engineering
9.
Biotechnol J ; 14(4): e1800461, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30320457

ABSTRACT

The development of bioprocesses capable of producing large numbers of human induced pluripotent stem cells (hiPSC) in a robust and safe manner is critical for the application of these cells in biotechnological and medical applications. Scalable expansion of hiPSC is often performed using polystyrene microcarriers, which have to be removed from the cell suspension using a separation step that causes loss of viable cells. In this study, application of novel xeno-free dissolvable microcarriers (DM) for an efficient and integrated expansion and harvesting of hiPSC is demonstrated. After an initial screening under static conditions, hiPSC culture using DM is performed in dynamic culture, using spinner-flasks. A maximum 4.0 ± 0.8-fold expansion is achieved after 5 days of culture. These results are validated with a second cell line and the culture is successfully adapted to fully xeno-free conditions. Afterwards, cell recovery is made within the spinner flask, being obtained a 92 ± 4% harvesting yield, which is significantly higher than the one obtained for the conventional filtration-based method (45 ± 3%). Importantly, the expanded and harvested hiPSC maintain their pluripotency and multilineage differentiation potential. The results here described represent a significant improvement of the downstream processing after microcarrier-based hiPSC expansion, leading to a more cost-effective and efficient bioprocess.


Subject(s)
Biotechnology/methods , Cell Culture Techniques/methods , Induced Pluripotent Stem Cells/cytology , Cell Differentiation/genetics , Cell Proliferation/genetics , Humans
10.
Prev Med ; 87: 22-34, 2016 06.
Article in English | MEDLINE | ID: mdl-26876624

ABSTRACT

INTRODUCTION: Although cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) prevention programmes have been effective in urban residents, their effectiveness in non-urban settings, where cardio-metabolic risk is typically elevated, is unknown. We systematically reviewed the effectiveness of primary prevention programmes aimed at reducing risk factors for CVD/T2DM, including blood pressure, body mass index (BMI), blood lipid and glucose, diet, lifestyle, and knowledge in adults residing in non-urban areas. METHODS: Twenty-five manuscripts, globally, from 1990 were selected for review (seven included in the meta-analyses) and classified according to: 1) study design (randomised controlled trial [RCT] or pre-/post-intervention); 2) intervention duration (short [<12months] or long term [≥12months]), and; 3) programme type (community-based programmes or non-community-based programmes). RESULTS: Multiple strategies within interventions focusing on health behaviour change effectively reduced cardio-metabolic risk in non-urban individuals. Pre-/post-test design studies showed more favourable improvements generally, while RCTs showed greater improvements in physical activity and disease and risk knowledge. Short-term programmes were more effective than long-term programmes and in pre-/post-test designs reduced systolic blood pressure by 4.02mmHg (95% CI -6.25 to -1.79) versus 3.63mmHg (95% CI -7.34 to 0.08) in long-term programmes. Community-based programmes achieved good results for most risk factors except BMI and (glycated haemoglobin) HbA1c. CONCLUSION: The setting for applying cardio-metabolic prevention programmes is important given its likelihood to influence programme efficacy. Further investigation is needed to elucidate the individual determinants of cardio-metabolic risk in non-urban populations and in contrast to urban populations.


Subject(s)
Cardiovascular Diseases/prevention & control , Diabetes Mellitus, Type 2/prevention & control , Primary Prevention , Exercise , Health Behavior , Humans , Life Style , Risk Factors , Rural Population
11.
Metab Eng ; 20: 29-41, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23994489

ABSTRACT

Violacein and deoxyviolacein are interesting therapeutics against pathogenic bacteria and viruses as well as tumor cells. In the present work, systems-wide metabolic engineering was applied to target Escherichia coli, a widely accepted recombinant host in pharmaceutical biotechnology, for production of these high-value products. The basic producer, E. coli dVio-1, that expressed the vioABCE cluster from Chromobacterium violaceum under control of the inducible araC system, accumulated 180 mg L(-1) of deoxyviolacein. Targeted intracellular metabolite analysis then identified bottlenecks in tryptophan supporting pathways, the major product building block. This was used for comprehensive engineering of serine, chorismate and tryptophan biosynthesis and the non-oxidative pentose-phosphate pathway. The final strain, E. coli dVio-6, accumulated 320 mg L(-1) deoxyviolacein in shake flask cultures. The created chassis of a high-flux tryptophan pathway was complemented by genomic integration of the vioD gene of Janthinobacterium lividum, which enabled exclusive production of violacein. In a fed-batch process, the resulting producer E. coli Vio-4 accumulated 710 mg L(-1) of the desired product. With straightforward broth extraction and subsequent crystallization, violacein could be obtained with 99.8% purity. This demonstrates the potential of E. coli as a platform for production of tryptophan based therapeutics.


Subject(s)
Antineoplastic Agents/metabolism , Chromobacterium/genetics , Escherichia coli , Genes, Bacterial , Indoles/metabolism , Metabolic Engineering , Multigene Family , Chromobacterium/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism
12.
Int J Parasitol ; 42(13-14): 1115-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23149245

ABSTRACT

To date, nothing is known about the genetic diversity of the Echinococcus neotropical species, Echinococcus vogeli and Echinococcus oligarthrus. Here we used mitochondrial and nuclear DNA sequence polymorphisms to uncover the genetic structure, transmission and history of E. vogeli in the Brazilian Amazon, based on a sample of 38 isolates obtained from human and wild animal hosts. We confirm that the parasite is partially synanthropic and show that its populations are diverse. Furthermore, significant geographical structuring is found, with western and eastern populations being genetically divergent.


Subject(s)
DNA, Mitochondrial/genetics , Echinococcus/classification , Echinococcus/genetics , Polymorphism, Genetic , Animals , Biological Evolution , Brazil/epidemiology , Demography , Echinococcosis/epidemiology , Echinococcosis/parasitology , Echinococcosis/veterinary , Humans
13.
Biotechnol Lett ; 34(4): 717-20, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22187076

ABSTRACT

Violacein and deoxyviolacein display a broad range of interesting biological properties but their production is rarely distinguished due to the lack of suitable analytical methods. An HPLC method has been developed for the separation and quantification of violacein and deoxyviolacein and can determine the content of both molecules in microbial cultures. A comparison of different production microorganisms, including recombinant Escherichia coli and the natural producer Janthinobacterium lividum, revealed that the formation of violacein and deoxyviolacein is strain-specific but showed significant variation during growth although the ratio between the two compounds remained constant.


Subject(s)
Biological Products/metabolism , Escherichia coli/metabolism , Indoles/metabolism , Oxalobacteraceae/metabolism , Biological Products/isolation & purification , Chemistry Techniques, Analytical/methods , Chromatography, High Pressure Liquid/methods , Escherichia coli/growth & development , Indoles/isolation & purification , Oxalobacteraceae/growth & development
14.
Electron. j. biotechnol ; 13(5): 5-6, Sept. 2010. ilus, tab
Article in English | LILACS | ID: lil-591887

ABSTRACT

Cellulase is a group of enzymes (endoglucanase, exoglucanase and beta-glucosidase) required for cellulosic feedstock hydrolysis during bioethanol production. The use of recombinant cellulase is a strategy to reduce the enzyme cost. In this context, the present work describes the construction of a cellulase expression vector (pEglABglA), which allowed constitutive co-expression of endoglucanase A (EglA) from an endophytic Bacillus pumilus and the hyperthermophilic beta-glucosidase A (BglA) from Fervidobacterium sp. in Escherichia coli. When compared to the non-modified strain DH5 alpha, the recombinant Escherichia coli DH5 alpha (pEglABglA) reduced fivefold the viscosity of the carboxymethylcellulose medium (CMC-M). Also, it presented almost 30-fold increase in reducing sugar released from CMC-M, enabling the recombinant strain to grow using CMC as the sole carbon and energy source. When cultivated in rich media, specific growth rates of recombinant E. coli strains BL21, JM101 and Top10 were higher than those of DH5 alpha and DH10B strains. The constructed plasmid (pEglABglA) can be used as backbone for further cellulase gene addition, which may enhance even more E. coli cellulolytic capacity and growth rate.


Subject(s)
Cellulases/metabolism , Escherichia coli/enzymology , Ethanol , Escherichia coli/growth & development , Hydrolysis , beta-Glucosidase/metabolism
15.
J. bras. psiquiatr ; 54(2): 94-97, abr.-jun. 2005. tab
Article in English | LILACS | ID: lil-438298

ABSTRACT

Objetivo: Investigar a gravidade de sintomas depressivos e ansiosos em pacientes com hipotireoidismo subclínico (HSC) e avaliar a sua relação com a função tireoidiana. Métodos: Participantes: 21 pacientes com HSC foram avaliados. Grupo-controle: 18 indivíduos com função tireoidiana normal. As escalas de depressão de Hamilton (HD) e de ansiedade de Hamilton (HA) foram utilizadas. Dosages de TSH, T3, T4 livre, anticorpos antimicrossomais e antiperoxidase foram realizadas. Resultados: Observamos uma elevação estatisticamente significativa nos escores da HD e HA no grupo HSC. Os pacientes com HSC apresentaram o escore médio no HD = 11,7 +- 7,9 e do grupo-controle HD = 5,5 +- 4,7 (p<0,01). Na HA, o grupo HSC apresentou um escore médio = 13,1 +- 8,3 e o controle = 6,6 +- 5,5 (p<0,01). Não observamos, entretanto, uma correlação entre a gravidade dos sintomas depressivos e ansiosos e os níveis de TSH (c=0,26, p=0,22; c=0,14, p=0,4; respectivamente}. Conclusões: Os pacientes com HSC da nossa amostra, comparados com indivíduos sem HSC, evidenciaram um aumento estatisticamente significativo dos sintomas depressivos e ansiosos.


Subject(s)
Humans , Male , Female , Adult , Anxiety/etiology , Anxiety/psychology , Case-Control Studies , Depression/etiology , Depression/psychology , Hypothyroidism/complications , Hypothyroidism/psychology , Thyroid Function Tests
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