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1.
Carbohydr Res ; 535: 108988, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38048747

RESUMO

Naturally occurring glycans are often found in a multivalent presentation. Cell surface receptors that recognize these displays may form clusters, which can lead to signalling or endocytosis. One of the challenges in generating synthetic displays of multivalent carbohydrates is providing high valency as well as access to heterofunctional conjugates to allow attachment of multiple antigens or payloads. We designed a strategy based on a set of bifunctional linkers to generate a heterobifunctional multivalent display of two carbohydrate antigens to bind BCR and CD22 with four and twelve antigen copies, respectively. We confirmed that the conjugates were able to engage both CD22 and BCR on cells by observing receptor clustering. The strategy is modular and would allow for alternative carbohydrate antigens to be attached bearing amine and alkyne groups and should be of interest for the development of immunomodulators and vaccines.


Assuntos
Sistema ABO de Grupos Sanguíneos , Glicoconjugados , Carboidratos , Polissacarídeos
2.
RSC Adv ; 13(46): 32641-32647, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37936646

RESUMO

Silicon carbide has a planar two-dimensional structure; therefore it is a potential material for constructing twisted bilayer systems for applications. In this study, DFT calculations were performed on four models with different twist angles. We chose angles of 21.8°, 17.9°, 13.2°, and 5.1° to estimate the dependence of the electronic and phononic properties on the twist angle. The results show that the band gap of bilayer SiC can be changed proportionally by changing the twist angle. However, there are only small variations in the band gaps, with an increment of 0.24 eV by changing the twist angle from 5.1° to 21.8°. At four considered twist angles, the band gaps decrease significantly when fixing the structure of each layer and pressing the separation distance down to 3.5 Å, 3.0 Å, 2.7 Å, and 2.5 Å. A noteworthy point is that the pressing also makes the band linearly smaller at a certain rate regardless of the twist angles. Meanwhile, the phonon bands are not affected by the value of the twist angle. The optical bands are between 900 cm-1 and 1100 cm-1 and the acoustic bands are between 0 cm-1 and 650 cm-1 at four twist angles.

3.
BJS Open ; 7(5)2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37862616

RESUMO

BACKGROUND: Groin hernia repair is one of the most common operations performed globally, with more than 20 million procedures per year. The last guidelines on groin hernia management were published in 2018 by the HerniaSurge Group. The aim of this project was to assess new evidence and update the guidelines. The guideline is intended for general and abdominal wall surgeons treating adult patients with groin hernias. METHOD: A working group of 30 international groin hernia experts and all involved stakeholders was formed and examined all new literature on groin hernia management, available until April 2022. Articles were screened for eligibility and assessed according to GRADE methodologies. New evidence was included, and chapters were rewritten. Statements and recommendations were updated or newly formulated as necessary. RESULTS: Ten chapters of the original HerniaSurge inguinal hernia guidelines were updated. In total, 39 new statements and 32 recommendations were formulated (16 strong recommendations). A modified Delphi method was used to reach consensus on all statements and recommendations among the groin hernia experts and at the European Hernia Society meeting in Manchester on October 21, 2022. CONCLUSION: The HerniaSurge Collaboration has updated the international guidelines for groin hernia management. The updated guidelines provide an overview of the best available evidence on groin hernia management and include evidence-based statements and recommendations for daily practice. Future guideline development will change according to emerging guideline methodology.


Assuntos
Parede Abdominal , Hérnia Inguinal , Adulto , Humanos , Hérnia Inguinal/cirurgia , Virilha/cirurgia , Telas Cirúrgicas
4.
Microbiol Res (Pavia) ; 14(2): 656-672, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37752971

RESUMO

Amoebozoa include lineages of diverse ecology, behavior, and morphology. They are assumed to encompass members with the largest genome sizes of all living things, yet genomic studies in the group are limited. Trichosphaerium, a polymorphic, multinucleate, marine amoeba with a complicated life cycle, has puzzled experts for over a century. In an effort to explore the genomic diversity and investigate extraordinary behavior observed among the Amoebozoa, we used integrated omics approaches to study this enigmatic marine amoeba. Omics data, including single-cell transcriptomics and cytological data, demonstrate that Trichosphaerium sp. possesses the complete meiosis toolkit genes. These genes are expressed in life stages of the amoeba including medium and large cells. The life cycle of Trichosphaerium sp. involves asexual processes via binary fission and multiple fragmentation of giant cells, as well as sexual-like processes involving genes implicated in sexual reproduction and polyploidization. These findings are in stark contrast to a life cycle previously reported for this amoeba. Despite the extreme morphological plasticity observed in Trichosphaerium, our genomic data showed that populations maintain a species-level intragenomic variation. A draft genome of Trichosphaerium indicates elevated lateral gene transfer (LGT) from bacteria and giant viruses. Gene trafficking in Trichosphaerium is the highest within Amoebozoa and among the highest in microbial eukaryotes.

5.
Breast Cancer Res Treat ; 202(2): 267-273, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37531016

RESUMO

PURPOSE: Axillary Lymph Node Dissection (ALND) is recommended for breast cancer patients who present with clinically node positive disease (cN1) especially if they have residual nodal disease (ypN+) following neoadjuvant therapy (NAT). It is unknown whether axillary dissection improves outcome for these patients. METHODS: A prospectively maintained database was used to identify all patients who were diagnosed with cTis-T4N1M0 breast cancer treated with NAT. RESULTS: In our study, of 292 cN1 breast cancer patients who received NAT, we compared ALND with targeted axillary surgery (TAS) in ypN+ patients. ALND was performed in 75% of the ypN+ subgroup, while 25% underwent TAS. Axillary recurrence occurred in four ALND patients, but no recurrence was observed in the TAS group (p = 0.21). Five-year axillary recurrence-free survival was 100% for TAS and 90% for ALND (p = 0.21). Overall survival at five years was 97% for TAS and 85% for ALND (p = 0.39). Disease-free survival rates at five years were 51% for TAS and 61% for ALND (p = 0.9). Clinicopathological variables were similar between the groups, although some differences were noted. ALND patients had smaller clinical tumor size, larger pathological tumor size, more lymph nodes retrieved, larger tumor deposits, higher rates of extranodal extension, and greater prevalence of macrometastatic nodal disease. Tumor subtype and size of lymph node tumor deposit independently predicted survival. CONCLUSION: Axillary recurrence is infrequent in cN1 patients treated with NAT. Our study found that ALND did not reduce the occurrence of axillary recurrence or enhance overall survival. It is currently uncertain which patients benefit from axillary dissection.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Terapia Neoadjuvante , Metástase Linfática/patologia , Excisão de Linfonodo/efeitos adversos , Linfonodos/cirurgia , Linfonodos/patologia , Axila/patologia , Biópsia de Linfonodo Sentinela
6.
BMC Public Health ; 23(1): 1412, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488595

RESUMO

BACKGROUND: Health outcomes among Agent Orange/dioxin (dioxin) victims are significant due to many individuals requiring daily assistance, informal care, and rehabilitation support. This study aimed to identify the information needs of informal caregivers of dioxin victims in Vietnam. METHODS: A cross-sectional study was conducted in Quynh Phu district, Thai Binh province - an area with a large number of dioxin victims, from June 2019 to June 2020. Quantitative data were collected from 124 caregivers of victims via structured interviews. Qualitative data were collected using semi-structured interview guides with in-depth interviews (IDI) (n = 36) and two focus group discussions (FGD) (n = 12). RESULTS: The results demonstrated that all caregivers of dioxin victims were family members, predominantly older (71.8%), 61.5 years old on average, living on low incomes (87.9%), and were farmers (80.7%). Almost all participants (96.8%) reported having information needs, particularly concerning dioxin's harms, nutrition, dioxin-related policies and rehabilitation, and psychological support for patients. Caregivers reported that they would like to receive information via health staff counselling (85.0%), television (75.0%), and community loudspeaker (65.8%). Notably, the majority of caregivers reported the need for information regarding psychological support (70.0%). These findings are consistent with qualitative data, which identify an urgent need to provide information, especially through health staff and digital resources. CONCLUSION: Many families with dioxin victims lived with little support and information, highlighting their high demand for information about care and rehabilitation. Thus, the healthcare system should promote information support, policy, and psychological support for caregivers and victims. An online support system for caregivers and victims is also recommended.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Humanos , Pessoa de Meia-Idade , Cuidadores , Vietnã , Estudos Transversais
7.
ACS Omega ; 8(28): 25424-25431, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483209

RESUMO

This work studied hydrogen adsorption by a two-dimensional silicon carbide using a combined molecular dynamics and density functional theory approach. The geometrical properties of partially and fully hydrogenated structures were investigated, considering the effect of zero-point energy. The preferred hydrogen atom location is on top of silicon atoms. The hydrogen interaction energies were obtained for the first time as the attractive force. For fully hydrogenated 2D SiC, the chair-like conformer is the most stable configuration, and the next is the boat-like conformer, while the table-like structure is not stable. The coverage and arrangement of the adsorbed hydrogen atoms significantly influence the values of the direct/indirect bandgaps of the considered systems, increasing the bandgap to 4.07, 3.64, and 4.41 eV for chair-like, table-like, and boat-like, respectively. Their dynamical stability was investigated by phonon dispersion calculations. The obtained results can serve as a guide for the application of hydrogenated two-dimensional silicon carbide in optoelectronic applications in manufacturing innovation.

8.
J Virol Methods ; 318: 114755, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37244432

RESUMO

Porcine epidemic diarrhea virus (PEDV) is a highly contagious intestinal virus. However, the current PEDV vaccine, which is produced from classical strain G1, offers low protection against recently emerged strain G2. This study aims to develop a better vaccine strain by propagating the PS6 strain, a G2b subgroup originating from Vietnam, on Vero cells until the 100th passage. As the virus was propagated, its titer increased, and its harvest time decreased. Analysis of the nucleotide and amino acid variation of the PS6 strain showed that the P100PS6 had 11, 4, and 2 amino acid variations in the 0 domain, B domain, and ORF3 protein, respectively, compared to the P7PS6 strain. Notably, the ORF3 gene was truncated due to a 16-nucleotide deletion mutation, resulting in a stop codon. The PS6 strain's virulence was evaluated in 5-day-old piglets, with P7PS6 and P100PS6 chosen for comparison. The results showed that P100PS6-inoculated piglets exhibited mild clinical symptoms and histopathological lesions, with a 100% survival rate. In contrast, P7PS6-inoculated piglets showed rapid and typical clinical symptoms of PEDV infection, and the survival rate was 0%. Additionally, the antibodies (IgG and IgA) produced from inoculated piglets with P100PS6 bound to both the P7PS6 and P100PS6 antigens. This finding suggested that the P100PS6 strain was attenuated and could be used to develop a live-attenuated vaccine against highly pathogenic and prevalent G2b-PEDV strains.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Chlorocebus aethiops , Suínos , Animais , Células Vero , Vírus da Diarreia Epidêmica Suína/genética , Virulência , Inoculações Seriadas , Vacinas Atenuadas/genética , Infecções por Coronavirus/epidemiologia , Diarreia/veterinária
9.
J Geriatr Oncol ; 14(4): 101503, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37126898

RESUMO

INTRODUCTION: Randomized studies support de-escalation of adjuvant therapy for a target population of older adults ≥65 years with stage I, estrogen-receptor (ER) positive breast cancer after breast conserving surgery. We sought to evaluate the impact of a simplified multidisciplinary clinic (s-MDC) in this population by comparing treatment patterns and patient perceptions of adjuvant radiation therapy (RT) and hormone therapy (HT) between patients seen in s-MDC vs. standard consultations. MATERIALS AND METHODS: Medical records were retrospectively reviewed for patients in the above target population who underwent surgery between August 2020 and May 2022 at our institution. Two cohorts were included: (1) patients seen in s-MDC, and (2) patients seen in standard clinic separately by medical and radiation oncology (non-s-MDC cohort). The non-s-MDC patients declined, could not attend, and/or were not referred to the s-MDC. Patients in the s-MDC cohort were prospectively administered validated questionnaires to evaluate patient reported data including the Decision Autonomy Preference Scale (DAPS), e-Prognosis, and Medical Maximizing-Minimizing Scale (MMS). Chi square, t-tests, and non-parametric equivalents compared demographics, and logistic regression evaluated RT and HT use and survey score outcomes between cohorts. RESULTS: A total of 127 patients met inclusion criteria, with 33 s-MDC and 94 non-s-MDC patients. There was no difference between the cohorts in age, margin status, histology, grade, or focality. In the s-MDC cohort there were significantly more patients without sentinel lymph node biopsy (71.3% vs 42.4%, p = 0.003) and mean tumor size was smaller (0.69 vs. 0.96 cm, p < 0.003), and Charlson comborbidity index (CCI) was higher (5.21 vs 4.96, p = 0.038). There was no significant difference in receipt of RT (65% s-MDC vs 77% standard; odds ratio [OR] = 0.55, p = 0.189), HT (78% ss-MDC vs 72% standard; OR = 1.36, p = 0.513), or both (50% s-MDC vs 59% standard; OR = 0.7, p = 0.429). The s-MDC cohort was significantly more likely to undergo accelerated (vs. standard hypofractionated) RT (70% vs 39%; OR = 3.59, p = 0.020). In s-MDC patients with completed questionnaires (n = 33), all whose selected "mostly patient (n=6)" based decision making by DAPS chose RT while all "mostly doctor (n=1)" chose no RT. Based on e-Prognosis, there were lower odds of RT for increasing Schonberg score/ higher 10 yr mortality risk (OR 0.600, p = 0.048). MMS score ≥ 40 ("maximizer") was strongly linked with the use of RT (OR 18.57, p = 0.011). DISCUSSION: For adults ≥65 years with early stage, ER positive breast cancer, s-MDC participation was not significantly associated with lower use of adjuvant RT or HT versus standard consultation but was significantly associated with shorter RT courses. DAPS and MMS results indicate that patient treatment preference may be predictable, highlighting an opportunity to tailor consultation discussions and recommendations based on intrinsic patient preferences and individual goals.


Assuntos
Neoplasias da Mama , Humanos , Idoso , Feminino , Neoplasias da Mama/patologia , Estudos Retrospectivos , Terapia Combinada , Prognóstico , Encaminhamento e Consulta , Radioterapia Adjuvante/métodos , Estadiamento de Neoplasias
10.
Urology ; 177: 181-183, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37044311

RESUMO

Urethral diverticula are rare in children, especially in the absence of trauma. We present a case of a 9-year-old girl with pain with micturition, incontinence, and recurrent urinary tract infections. Diagnosis of urethral diverticulum was made by magnetic resonance imaging. A robot-assisted transabdominal laparoscopic diverticulectomy was performed without complication. The patient experienced a significant improvement in symptoms.


Assuntos
Divertículo , Laparoscopia , Robótica , Doenças Uretrais , Incontinência Urinária , Feminino , Humanos , Criança , Uretra , Doenças Uretrais/complicações , Incontinência Urinária/etiologia , Divertículo/complicações , Divertículo/cirurgia , Divertículo/diagnóstico , Laparoscopia/efeitos adversos
11.
Comput Biol Med ; 155: 106695, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36805230

RESUMO

Dental pain invokes the sympathetic nervous system, which can be measured by electrodermal activity (EDA). In the dental clinic, accurate quantification of pain is needed because it could enable optimized drug-dose treatments, thereby potentially reducing drug addiction. However, a confounding factor is that during pain there is also lingering residual stress, hence, both contribute to the EDA response. Therefore, we investigated whether EDA can differentiate stress from pain during dental examination. The use of electrical pulp test (EPT) is an ideal approach to tease out the dynamics of stress and mimic pain with lingering residual stress. Once the electrical sensation is felt and reaches a critical current threshold, the subject removes the probe from their tooth, hence, this stage of data represents largely EPT stimulus and the residual stress-induced EDA response is smaller. EPT was performed on necrotic and vital teeth in fifty-one subjects. We defined four different data groups of reactions based on each individual's EPT intensity level expectation based on the visual analog scale (VAS) of their baseline trial, as follows: mild stress, mild stress + EPT, strong stress, and strong stress + EPT. EDA-derived features exhibited significant difference between residual lingering stress + EPT groups and stress groups. We obtained 84.6% accuracy with 76.2% sensitivity and 86.8% specificity with multilayer perceptron in differentiating between pure-stress groups vs. stress + EPT groups. Moreover, EPT induced much greater EDA amplitude and faster response than stress. Our finding suggests that our machine learning approach can discriminate between stress and EPT stimulation in EDA signals.


Assuntos
Resposta Galvânica da Pele , Dor , Humanos , Clínicas Odontológicas , Sistema Nervoso Simpático/fisiologia , Aprendizado de Máquina
12.
Vet Res Commun ; 47(1): 191-205, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35633471

RESUMO

Highly pathogenic avian influenza viruses (HPAIV) have been responsible for causing several severe outbreaks across the world. To protect poultry farms and to prevent the possible spread of new influenza pandemics, vaccines that are both efficacious and low-cost are in high demand. We produced stable, large hemagglutinin H5 oligomers in planta by the specific interaction between S•Tag and S•Protein. H5 oligomers combined via S•Tag::S•Protein interaction in plant crude extracts induced strong humoral immune responses, strong neutralizing antibody responses, and resistance in chickens after challenge with a wild type HPAIV H5 virus strain. In all three parameters, plant crude extracts with H5 oligomers induced better responses than crude extracts containing trimers. The neutralizing antibodies induced by by two-dose and one dose immunization with an adjuvanted crude extract containing H5 oligomer protected vaccinated chickens from two lethal H5N1 virus strains with the efficiency of 92% and 100%, respectively. Following housing vaccinated chickens together with ten non-immunized chickens, only one of these chickens had detectable levels of the H5N1 virus. To facilitate the easy storage of a candidate vaccine, the H5 oligomer crude extracts were mixed with adjuvants and stored for 3.5 and 5.5 months at 4 °C, and chickens were immunized with these crude extracts. All these vaccinated chickens survived after a lethal H5N1 virus challenge. H5 oligomer crude extracts are comparable to commercial vaccines as they also induce strong virus-neutralizing immune responses following the administration of a single dose. The cost-effective production of plant crude extract vaccine candidates and the high stability after long-term storage will enable and encourage the further exploration of this technology for veterinary vaccine development.


Assuntos
Virus da Influenza A Subtipo H5N1 , Vacinas contra Influenza , Influenza Aviária , Animais , Hemaglutininas , Galinhas , Anticorpos Antivirais , Anticorpos Neutralizantes , Vacinação/veterinária
13.
Int Endod J ; 56(3): 356-368, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36367715

RESUMO

AIMS: To explore whether electrodermal activity (EDA) can serve as a complementary tool for pulpal diagnosis (Aim 1) and an objective metric to assess dental pain before and after local anaesthesia (Aim 2). METHODOLOGY: A total of 53 subjects (189 teeth) and 14 subjects (14 teeth) were recruited for Aim 1 and Aim 2, respectively. We recorded EDA using commercially available devices, PowerLab and Galvanic Skin Response (GSR) Amplifier, in conjunction with cold and electric pulp testing (EPT). Participants rated their level of sensation on a 0-10 visual analogue scale (VAS) after each test. We recorded EPT-stimulated EDA activity before and after the administration of local anaesthesia for participants who required root canal treatment (RCT) due to painful pulpitis. The raw data were converted to the time-varying index of sympathetic activity (TVSymp), a sensitive and specific parameter of EDA. Statistical analysis was performed using Python 3.6 and its Scikit-post hoc library. RESULTS: Electrodermal activity was upregulated by the stimuli of cold and EPT testing in the normal pulp. TVSymp signals were significantly increased in vital pulp compared to necrotic pulp by both cold test and EPT. Teeth that exhibited intensive sensitivity to cold with or without lingering pain had increased peak numbers of TVSymp than teeth with mild sensation to cold. Pre- and post-anaesthesia EDA activity and VAS scores were recorded in patients with painful pulpitis. Post-anaesthesia EDA signals were significantly lower compared to pre-anaesthesia levels. Approximately 71% of patients (10 of 14 patients) experienced no pain during treatment and reported VAS score of 0 or 1. The majority of patients (10 of 14) showed a reduction of TVSymp after the administration of anaesthesia. Two of three patients who experienced increased pain during RCT (post-treatment VAS > pre-treatment VAS) exhibited increased post-anaesthesia TVSymp. CONCLUSIONS: Our data show promising results for using EDA in pulpal diagnosis and for assessing dental pain. Whilst our testing was limited to subjects who had adequate communication skills, our future goal is to be able to use this technology to aid in the endodontic diagnosis of patients who have limited communication ability.


Assuntos
Pulpite , Humanos , Pulpite/diagnóstico , Pulpite/terapia , Resposta Galvânica da Pele , Medição da Dor/métodos , Dor/diagnóstico , Dor/etiologia , Polpa Dentária
14.
J Abdom Wall Surg ; 2: 11195, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38312421

RESUMO

Introduction: Of the more than 20 million patients undergoing groin hernia repair annually worldwide, 6% are scrotal hernias in high resource countries rising to 67% in low resource countries which represents a heavy disease burden on relatively young men during their most productive period of life. There are many open questions concerning management of scrotal hernia. These guidelines aim to improve the care for scrotal hernia patients by reducing recurrence rates, chronic pain and infection. Methods: After developing 19 key questions a systematic literature review was performed till 31 March 2021 for all relevant publications with search terms related to Scrotal Hernia. The articles were scored by all co-authors according to Oxford, SIGN and Grade methodologies. Statements and recommendations were formulated. Online Consensus meetings with 25 HerniaSurge members were organised with voting and grading Recommendations as "strong" (recommendations) or "weak" (suggestions) and by consensus, in some cases upgraded. Results: Only 23 articles (two level 2 registry and 21 level 3-5) were selected. It is proposed to define scrotal hernia as an inguinal hernia which has descended into and causes any scrotal distortion. A new classification for scrotal hernias was proposed based on hernia size, SI for upper third thigh, SII for middle thigh and SIII for lower third thigh or below. Irreducibility is denoted with IR. Despite weak evidence antibiotic prophylaxis is recommended. Urinary catheterization is recommended (upgraded) in complex cases (S2-3) due to prolonged operative time. Scrotal hernia repairs have higher associated morbidity and mortality compared to non-complex groin hernia repairs irrespective of surgical experience. Open anterior (mesh) approach is commonest technique and suture techniques in low resource countries. For minimally invasive approaches, TAPP resulted in less conversion to open approach compared to TEP. Conclusion: Although the evidence is scarce and often low quality scrotal hernia management guidelines aim to lead to better surgical outcomes irrespective of where patients live. This necessarily means a more tailored approach based on available resources and appropriate skills. The guidelines provide an impetus for future research where adoption of proposed classification will enable more meaningful comparison of different techniques for different hernia sizes.

15.
Front Microbiol ; 14: 1305778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38260905

RESUMO

Fomes fomentarius and Daedaleopsis tricolor produced significant amounts of water-insoluble melanins, and our previous study successfully enhanced their water solubility by arginine modification. This research aimed to investigate the anti-ultraviolet, antibacterial, and biofilm eradication activities of both the melanins and arginine-modified melanin (melanin derivatives) from these two fungi against an acne-causing bacterium (Cutibacterium acnes). Apart from these, the cytotoxicity of the melanins and melanin derivatives on human skin cells was also evaluated. Melanin derivatives of both two fungi showed significantly higher antibacterial and biofilm eradication activities compared with their original forms. Specifically, the MIC50 values of the melanin derivatives (1,000 µg/mL) are the same as those of erythromycin. Regarding biofilm eradication capacity, the MBEC50 value of D. tricolor melanin derivative (250 µg/mL) was just half of both erythromycin and F. fomentarius melanin derivative. However, it required a 2-fold higher concentration of melanin derivatives than erythromycin to inhibit 90% of the bacterial population and eradicate 90% of their biofilm. Regarding anti-ultraviolet activity, blending melanins or melanin derivatives with a moisturizer/sunscreen enhanced their UV light absorption and the sun protection factor (SPF) values. In addition, melanins showed better effects than their derivatives, and those of D. tricolor were better than F. fomentarius. Remarkably, adding D. tricolor melanin (10%) to a Nivea pure cream could turn this cream into a broad-spectrum sunscreen, with its SPF value and critical wavelength increasing from 7.74 and 338.67 to 14.02 and 377.0, respectively. In addition, adding melanin or a melanin derivative of D. tricolor to an Olay sunscreen enhanced the SPF and the critical wavelength of the sunscreen from 17.25 and 371.67 to 23.82 and 374 and 23.38 and 372, respectively. Notably, melanins and melanin derivatives showed no toxicity in human fibroblasts. The obtained data suggest that arginine modification significantly enhanced the antibacterial and biofilm eradication activities of melanins from D. tricolor and F. fomentarius. However, this is not the case when it comes to their anti-ultraviolet activities. In addition, melanin and melanin derivatives from D. tricolor are potential candidates for anti-acne sunscreen products and are worth further investigation.

16.
RSC Chem Biol ; 3(10): 1260-1275, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36320887

RESUMO

Synthetic glycoconjugates are used in the development of vaccines and the design of inhibitors for glycan-protein interactions. The in vivo persistence of synthetic glycoconjugates is an important factor in their efficacy, especially when prolonged interactions with specific cell types may be required. In this study, we applied a strategy for non-covalent association of an active compound with serum proteins for extension of glycoconjugate half-life in serum. The small molecule, AG10, has previously been used to extend the half-life of small molecules through its high affinity for transthyretin (TTR), a serum protein. Using a tetravalent polyethylene glycol (PEG)-based scaffold we developed a synthetic strategy for glycoconjugates that allowed for controlled addition of multiple tags, such as a TTR affinity tag or fluorophore. We designed a version of AG10 modified at the pyrazole core, named GD10, amenable to our conjugation strategy and introduced to glycoconjugates using a tri-functional linker. This approach allowed for attachment of GD10 and fluorophore tags, as well as carbohydrate antigens. We then tested the influence of the GD10 tag on glycoconjugate half-life in vivo using a mouse model. Our results suggest that the combination of the GD10 tag and the PEG scaffold extended the half-life of glycoconjugates by as much as 10-fold when compared to proteins of similar molecular weight. The GD10 tag was able to extend the half-life of similar glycoconjugates by as much as 2-fold. We observed a role for the terminal saccharide residue of the carbohydrate antigen and confirmed that conjugates were able to penetrate multiple compartments in vivo including bone marrow, lymph nodes, and other organs. The introduction of the GD10 tag did not obstruct the ability of conjugates to interact with lectin receptors. We conclude that serum protein binders can be used to extend the persistence of glycoconjugates in vivo.

17.
Biophys Rep (N Y) ; 2(3): 100064, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36425332

RESUMO

The B cell membrane expresses sialic-acid-binding immunoglobulin-like lectins, also called Siglecs, that are important for modulating immune response. Siglecs have interactions with sialoglycoproteins found on the same membrane (cis-ligands) that result in homotypic and heterotypic receptor clusters. The regulation and organization of these clusters, and their effect on cell activation, is not clearly understood. We investigated the role of human neuraminidase enzymes NEU1 and NEU3 on the clustering of CD22 on B cells using confocal microscopy. We observed that native NEU1 and NEU3 activity influence the cluster size of CD22. Using single-particle tracking, we observed that NEU3 activity increased the lateral mobility of CD22, which was in contrast to the effect of exogenous bacterial NEU enzymes. Moreover, we show that native NEU1 and NEU3 activity influenced cellular Ca2+ levels, supporting a role for these enzymes in regulating B cell activation. Our results establish a role for native NEU activity in modulating CD22 organization and function on B cells.

18.
J Fungi (Basel) ; 8(9)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36135681

RESUMO

Medicinal plants play important roles in traditional medicine, and numerous compounds among them have been recognized for their antimicrobial activity. However, little is known about the potential of Vietnamese medicinal plants for antifungal activity. In this study, we examined the antagonistic activity of twelve medicinal plant species collected in Northern Vietnam against Penicillium digitatum, Aspergillus flavus, Aspergillus fumigatus, and Candida albicans. The results showed that the antifungal activities of the crude extracts from Mahonia bealei, Ficus semicordata, and Gnetum montanum were clearly detected with the citrus postharvest pathogen P. digitatum. These extracts could fully inhibit the growth of P. digitatum on the agar medium, and on the infected citrus fruits at concentrations of 300-1000 µg/mL. Meanwhile, the other tested fungi were less sensitive to the antagonistic activity of the plant extracts. In particular, we found that the ethanolic extract of M. bealei displayed a broad-spectrum antifungal activity against all four pathogenic fungi. Analysis of this crude extract by enrichment coupled with high-performance liquid chromatography revealed that berberine and palmatine are major metabolites. Additional inspections indicated berberine as the key compound responsible for the antifungal activity of the M. bealei ethanolic extract. Our study provides a better understanding of the potential of Vietnamese medicinal plant resources for combating fungal pathogens. This work also highlights that the citrus pathogen P. digitatum can be employed as a model fungus for screening the antifungal activity of botanicals.

19.
Front Vet Sci ; 9: 940395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967993

RESUMO

Porcine epidemic diarrhea virus (PEDV) is a serious infectious causative agent in swine, especially in neonatal piglets. PEDV genotype 2 (G2) strains, particularly G2a, were the primary causes of porcine epidemic diarrhea (PED) outbreaks in Vietnam. Here, we produced a plant-based CO-26K-equivalent epitope (COE) variant from a Vietnamese highly virulent PEDV strain belonging to genotype 2a (COE/G2a) and evaluated the protective efficacy of COE/G2a-GCN4pII protein (COE/G2a-pII) in piglets against the highly virulent PEDV G2a strain following passive immunity. The 5-day-old piglets had high levels of PEDV-specific IgG antibodies, COE-IgA specific antibodies, neutralizing antibodies, and IFN-γ responses. After virulent challenge experiments, all of these piglets survived and had normal clinical symptoms, no watery diarrhea in feces, and an increase in their body weight, while all of the negative control piglets died. These results suggest that the COE/G2a-pII protein produced in plants can be developed as a promising vaccine candidate to protect piglets against PEDV G2a infection in Vietnam.

20.
Sci Rep ; 12(1): 9841, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701521

RESUMO

To date, genomic analyses in amoebozoans have been mostly limited to model organisms or medically important lineages. Consequently, the vast diversity of Amoebozoa genomes remain unexplored. A draft genome of Cochliopodium minus, an amoeba characterized by extensive cellular and nuclear fusions, is presented. C. minus has been a subject of recent investigation for its unusual sexual behavior. Cochliopodium's sexual activity occurs during vegetative stage making it an ideal model for studying sexual development, which is sorely lacking in the group. Here we generate a C. minus draft genome assembly. From this genome, we detect a substantial number of lateral gene transfer (LGT) instances from bacteria (15%), archaea (0.9%) and viruses (0.7%) the majority of which are detected in our transcriptome data. We identify the complete meiosis toolkit genes in the C. minus genome, as well as the absence of several key genes involved in plasmogamy and karyogamy. Comparative genomics of amoebozoans reveals variation in sexual mechanism exist in the group. Similar to complex eukaryotes, C. minus (some amoebae) possesses Tyrosine kinases and duplicate copies of SPO11. We report a first example of alternative splicing in a key meiosis gene and draw important insights on molecular mechanism of sex in C. minus using genomic and transcriptomic data.


Assuntos
Amoeba , Amebozoários , Amoeba/genética , Amebozoários/genética , Evolução Molecular , Genoma/genética , Genômica , Meiose/genética , Filogenia
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