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1.
PLoS Pathog ; 20(4): e1012140, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598600

RESUMO

The Giardia lamblia virus (GLV) is a non-enveloped icosahedral dsRNA and endosymbiont virus that infects the zoonotic protozoan parasite Giardia duodenalis (syn. G. lamblia, G. intestinalis), which is a pathogen of mammals, including humans. Elucidating the transmission mechanism of GLV is crucial for gaining an in-depth understanding of the virulence of the virus in G. duodenalis. GLV belongs to the family Totiviridae, which infects yeast and protozoa intracellularly; however, it also transmits extracellularly, similar to the phylogenetically, distantly related toti-like viruses that infect multicellular hosts. The GLV capsid structure is extensively involved in the longstanding discussion concerning extracellular transmission in Totiviridae and toti-like viruses. Hence, this study constructed the first high-resolution comparative atomic models of two GLV strains, namely GLV-HP and GLV-CAT, which showed different intracellular localization and virulence phenotypes, using cryogenic electron microscopy single-particle analysis. The atomic models of the GLV capsids presented swapped C-terminal extensions, extra surface loops, and a lack of cap-snatching pockets, similar to those of toti-like viruses. However, their open pores and absence of the extra crown protein resemble those of other yeast and protozoan Totiviridae viruses, demonstrating the essential structures for extracellular cell-to-cell transmission. The structural comparison between GLV-HP and GLV-CAT indicates the first evidence of critical structural motifs for the transmission and virulence of GLV in G. duodenalis.


Assuntos
Giardia lamblia , Giardiavirus , Giardia lamblia/ultraestrutura , Giardia lamblia/patogenicidade , Giardiavirus/genética , Microscopia Crioeletrônica , Animais , Capsídeo/ultraestrutura , Capsídeo/metabolismo , Humanos , Filogenia
2.
Microb Pathog ; 191: 106675, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705216

RESUMO

Bovine mastitis, caused by Streptococcus agalactiae (Group B Streptococcus; GBS), poses significant economic challenges to the global dairy industry. Mouse models serves as valuable tools for assessing GBS-induced infections as an alternative to large animals. This study aimed to investigate the LD50 dose, organ bacterial load, and quantification of peritoneal leukocyte populations for GBS serotypes Ia and II isolates from China and Pakistan. Additionally, we measured indicators such as lactoferrin, albumin, and myeloperoxidase (MPO) activity. Pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, and IL-2) and anti-inflammatory cytokines (IL-10 and TGF-ß) in serum and tissue samples were evaluated using ELISA and qPCR, respectively. BALB/c mice (4 mice per group) received individual intraperitoneal injections of 100 µl containing specific bacterial inoculum concentrations (ranging from 105 to 109 CFU per mouse) of Chinese and Pakistani GBS isolates (serotypes Ia and II). Control groups received 100 µL of sterile PBS. Results revealed that the LD50 bacterial dose causing 50 % mortality in mice was 107 CFU. The highest bacterial load in all experimental groups was quantified in the peritoneum, followed by blood, mammary gland, liver, spleen, lungs, and brain. The most significant bacterial dissemination was observed in mice inoculated with Pakistani serotype Ia at 24 h, with a subsequent notable decline in bacterial counts at day 3. Notably, infection with Pakistani serotype Ia showed a trend of increased total leukocyte counts, significantly higher than Pakistani serotype II, Chinese Serotype Ia, and Chinese serotype II. A substantial influx of neutrophils and lymphocytes was observed in response to all tested serotypes, with Pakistani serotype Ia inducing a significantly higher influx compared to other groups (Pakistani serotype II, Chinese serotype Ia, and Chinese serotype II). Furthermore, TNF-α, IL-1ß, IL-2, and IL-6 expressions were significantly increased in mice one day after infection with the Pakistani serotype Ia. Compared to mice infected with the Pakistani serotype II, Chinese Serotype Ia, and Chinese serotype II, those infected with the Pakistani serotype Ia isolate exhibited the highest production of IL-10 and TGF-ß, along with significantly increased concentrations of lactoferrin, albumin, and MPO. These findings suggest that the persistence and severity of infection caused by the Pakistani serotype Ia may be linked to its ability to spread to deeper tissues. This study enhances our understanding of the clinical characteristics of bovine mastitis caused by S. agalactiae in China and Pakistan.


Assuntos
Citocinas , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Sorogrupo , Infecções Estreptocócicas , Streptococcus agalactiae , Animais , Streptococcus agalactiae/patogenicidade , Streptococcus agalactiae/classificação , Streptococcus agalactiae/imunologia , Streptococcus agalactiae/genética , Camundongos , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/imunologia , China , Citocinas/metabolismo , Citocinas/sangue , Feminino , Paquistão , Carga Bacteriana , Bovinos , Dose Letal Mediana , Mastite Bovina/microbiologia
3.
Soft Matter ; 20(18): 3787-3797, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639209

RESUMO

Breath figure imprinting, based on surface instabilities combined with fast polymer evaporation in a humid environment, enables the creation of micro-patterned membranes with tailored pore sizes. Despite being a simple procedure, it is still challenging to fully understand the dynamics behind the formation of hierarchical structuring. In this work, we used the breath figure technique to prepare porous PLA-based (polylactic acid) membranes with two distinctive additives, polyvinylidene fluoride (PVDF) and zinc oxide nanoparticles (ZnO NPs). The selection of these additives was governed by their unique properties and the potential synergistic effects; when blended with PLA, the addition of NPs leads to more uniform structures with tunable characteristics and potential multifunctionality. This article sheds light on the multifaced interactions that intricate the interplays between PLA, PVDF, and ZnO, thus governing their assembly. Through a comprehensive investigation, we scrutinize the impact of blending PVDF and different concentrations of ZnO NPs on the morphology and chemical properties of the final self-assembled PLA membranes while presenting an advanced understanding of the potential applications of PLA-self-assembly porous membranes in various industrial sectors.

4.
Small ; 19(50): e2302718, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37501325

RESUMO

Lithium-ion batteries (LIBs) have significantly impacted the daily lives, finding broad applications in various industries such as consumer electronics, electric vehicles, medical devices, aerospace, and power tools. However, they still face issues (i.e., safety due to dendrite propagation, manufacturing cost, random porosities, and basic & planar geometries) that hinder their widespread applications as the demand for LIBs rapidly increases in all sectors due to their high energy and power density values compared to other batteries. Additive manufacturing (AM) is a promising technique for creating precise and programmable structures in energy storage devices. This review first summarizes light, filament, powder, and jetting-based 3D printing methods with the status on current trends and limitations for each AM technology. The paper also delves into 3D printing-enabled electrodes (both anodes and cathodes) and solid-state electrolytes for LIBs, emphasizing the current state-of-the-art materials, manufacturing methods, and properties/performance. Additionally, the current challenges in the AM for electrochemical energy storage (EES) applications, including limited materials, low processing precision, codesign/comanufacturing concepts for complete battery printing, machine learning (ML)/artificial intelligence (AI) for processing optimization and data analysis, environmental risks, and the potential of 4D printing in advanced battery applications, are also presented.

5.
Ann Surg Oncol ; 30(3): 1914-1925, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36437409

RESUMO

PURPOSE: The proximal tibia is a common location for osteosarcoma. Modular endoprosthesis is a popular reconstructive option, yet it has been associated with many complications. Our study aimed to evaluate the functional outcome and complications of proximal tibial osteosarcoma patients treated by limb salvage using modular endoprosthesis. METHODS: A retrospective study of a prospective database was performed during the period between January 2000 and July 2017. Fifty-five patients with proximal tibial osteosarcoma underwent resection and modular endoprosthetic reconstruction. The functional outcome was evaluated using the Musculoskeletal tumor society scoring system and knee range of motion. Postoperative complications were classified according to Henderson classification; Type 1 (soft tissue failure), Type 2 (aseptic loosening), Type 3 (structural failure), Type 4 (infection) and Type 5 (local tumor progression). RESULTS: The mean follow-up period was 71.69 ± 49.76 months. The mean musculoskeletal tumor society score was 26.5 ± 2.22; the mean range of motion was 72.63 ± 25.07, and the mean extension lag was 15.09 ± 15.38. Type 1, type 2, type 3, type 4, and type 5 complications occurred in 7.3%, 14.5%, 21.8%, 23.6%, and 5.5%, respectively. Chest metastasis developed in 10 patients (18.2%). The estimated 5-year and 10-year survival rates for the treated patients were 83.6% and 79.9%. CONCLUSIONS: Proximal tibial osteosarcoma reconstruction with a modular endoprosthesis is a reliable treatment option for retaining limb function. Most complications are manageable.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Tíbia/cirurgia , Tíbia/patologia , Estudos Retrospectivos , Neoplasias Ósseas/patologia , Resultado do Tratamento , Osteossarcoma/cirurgia , Osteossarcoma/patologia , Próteses e Implantes , Salvamento de Membro
6.
Cytokine ; 169: 156268, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37320965

RESUMO

Cytokines are a protein family comprising interleukins, lymphokines, chemokines, monokines and interferons. They are significant constituents of the immune system, and they act in accordance with specific cytokine inhibiting compounds and receptors for the regulation of immune responses. Cytokine studies have resulted in the establishment of newer therapies which are being utilized for the treatment of several malignant diseases. The advancement of these therapies has occurred from two distinct strategies. The first strategy involves administrating the recombinant and purified cytokines, and the second strategy involves administrating the therapeutics which inhibits harmful effects of endogenous and overexpressed cytokines. Colony stimulating factors and interferons are two exemplary therapeutics of cytokines. An important effect of cytokine receptor antagonist is that they can serve as anti-inflammatory agents by altering the treatments of inflammation disorder, therefore inhibiting the effects of tumour necrosis factor. In this article, we have highlighted the research behind the establishment of cytokines as therapeutics and vaccine adjuvants, their role of immunotolerance, and their limitations.


Assuntos
Adjuvantes de Vacinas , Citocinas , Citocinas/metabolismo , Interferons/fisiologia , Fatores Imunológicos , Interleucinas/fisiologia , Imunoterapia
7.
Sensors (Basel) ; 23(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36772430

RESUMO

The early, valid prediction of heart problems would minimize life threats and save lives, while lack of prediction and false diagnosis can be fatal. Addressing a single dataset alone to build a machine learning model for the identification of heart problems is not practical because each country and hospital has its own data schema, structure, and quality. On this basis, a generic framework has been built for heart problem diagnosis. This framework is a hybrid framework that employs multiple machine learning and deep learning techniques and votes for the best outcome based on a novel voting technique with the intention to remove bias from the model. The framework contains two consequent layers. The first layer contains simultaneous machine learning models running over a given dataset. The second layer consolidates the outputs of the first layer and classifies them as a second classification layer based on novel voting techniques. Prior to the classification process, the framework selects the top features using a proposed feature selection framework. It starts by filtering the columns using multiple feature selection methods and considers the top common features selected. Results from the proposed framework, with 95.6% accuracy, show its superiority over the single machine learning model, classical stacking technique, and traditional voting technique. The main contribution of this work is to demonstrate how the prediction probabilities of multiple models can be exploited for the purpose of creating another layer for final output; this step neutralizes any model bias. Another experimental contribution is proving the complete pipeline's ability to be retrained and used for other datasets collected using different measurements and with different distributions.


Assuntos
Aprendizado de Máquina , Probabilidade
8.
Sensors (Basel) ; 23(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36904639

RESUMO

In this research paper, the spatial distributions of five different services-Voice over Internet Protocol (VoIP), Video Conferencing (VC), Hypertext Transfer Protocol (HTTP), and Electronic Mail-are investigated using three different approaches: circular, random, and uniform approaches. The amount of each service varies from one to another. In certain distinct settings, which are collectively referred to as mixed applications, a variety of services are activated and configured at predetermined percentages. These services run simultaneously. Furthermore, this paper has established a new algorithm to assess both the real-time and best-effort services of the various IEEE 802.11 technologies, describing the best networking architecture as either a Basic Service Set (BSS), an Extended Service Set (ESS), or an Independent Basic Service Set (IBSS). Due to this fact, the purpose of our research is to provide the user or client with an analysis that suggests a suitable technology and network configuration without wasting resources on unnecessary technologies or requiring a complete re-setup. In this context, this paper presents a network prioritization framework for enabling smart environments to determine an appropriate WLAN standard or a combination of standards that best supports a specific set of smart network applications in a specified environment. A network QoS modeling technique for smart services has been derived for assessing best-effort HTTP and FTP, and the real-time performance of VoIP and VC services enabled via IEEE 802.11 protocols in order to discover more optimal network architecture. A number of IEEE 802.11 technologies have been ranked by using the proposed network optimization technique with separate case studies for the circular, random, and uniform geographical distributions of smart services. The performance of the proposed framework is validated using a realistic smart environment simulation setting, considering both real-time and best-effort services as case studies with a range of metrics related to smart environments.

9.
Int J Mol Sci ; 24(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37834266

RESUMO

A novel derivative of ciprofloxacin (Cpx) was synthesized and characterized using various analytical techniques, including FT-IR spectroscopy, UV-Vis spectroscopy, TEM and SEM analysis, 1H NMR, 13C NMR, and HPLC analysis. The newly prepared Cpx derivative (Cpx-Drv) exhibited significantly enhanced antibacterial properties compared to Cpx itself. In particular, Cpx-Drv demonstrated a 51% increase in antibacterial activity against S. aureus and a 30% improvement against B. subtilis. It displayed potent inhibitory effects on topoisomerases II (DNA gyrase and topoisomerase IV) as potential molecular targets, with IC50 values of 6.754 and 1.913 µg/mL, respectively, in contrast to Cpx, which had IC50 values of 2.125 and 0.821 µg/mL, respectively. Docking studies further supported these findings, showing that Cpx-Drv exhibited stronger binding interactions with the gyrase enzyme (PDB ID: 2XCT) compared to the parent Cpx, with binding affinities of -10.3349 and -7.7506 kcal/mole, respectively.


Assuntos
Ciprofloxacina , Staphylococcus aureus , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Antibacterianos/química , DNA Girase , Simulação de Acoplamento Molecular , Inibidores da Topoisomerase II/farmacologia , Inibidores da Topoisomerase II/química
10.
J Environ Manage ; 347: 119105, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37783083

RESUMO

Unconventional treatments can provide a modification to convert ash waste into valuable materials that can be used in various applications. This study focuses on bottom ash (BA) collected from a local incineration plant and characterizes its chemical composition before and after pretreatment by coating with polymers. The toxicity-characteristic leaching procedure (TCLP) was used to identify selected heavy metal leaching after treatment with vinyl-terminated polydimethylsiloxane (PDMS) of different molecular weights. BA coatings were incorporated in two ratios, 0.5% and 1%, by milling to avoid heavy metal leaching. The results showed that all the coating batches had reduced concentrations of copper (Cu), manganese (Mn), and zinc (Zn), whereas the concentrations of chromium (Cr) and cadmium (Cd) showed higher amounts of BAV34 (0.5%) and BAV25 (1%). The treated BA with GP demonstrated percentages of reduction of 70%, 65%, 80%, 75%, 90%, and 80% for Cu, Mn, Ni, Zn, Pb, and Cd, respectively. The milling procedure reduced the particle size of the coated ash. Hydrophobicity was observed in all coating batches compared to untreated BA. The thermogravimetric analysis (TGA) results showed variations between BA and treated BA, which confirmed that PDMS caused surface modification. These features have potential significance for extending the use of coated ash as a sustainable material for construction applications.


Assuntos
Metais Pesados , Eliminação de Resíduos , Incineração , Resíduos Sólidos/análise , Cinza de Carvão , Cádmio , Metais Pesados/química , Zinco/análise , Manganês/análise , Eliminação de Resíduos/métodos
11.
Chembiochem ; 23(8): e202200133, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35263494

RESUMO

Di-ubiquitin (diUB) conjugates of defined linkages are useful tools for probing the functions of UB ligases, UB-binding proteins and deubiquitinating enzymes (DUBs) in coding, decoding and editing the signals carried by the UB chains. Here we developed an efficient method for linkage-specific synthesis of diUB probes based on the incorporation of the unnatural amino acid (UAA) Nϵ -L-thiaprolyl-L-Lys (L-ThzK) into UB for ligation with another UB at a defined Lys position. The diUB formed by the UAA-mediated ligation reaction has a G76C mutation on the side of donor UB for conjugation with E2 and E3 enzymes or undergoing dethiolation to generate a covalent trap for DUBs. The development of UAA mutagenesis for diUB synthesis provides an easy route for preparing linkage-specific UB-based probes to decipher the biological signals mediated by protein ubiquitination.


Assuntos
Aminoácidos , Ubiquitina , Aminoácidos/metabolismo , Lisina/metabolismo , Ubiquitina/metabolismo , Ubiquitinação
12.
Opt Express ; 30(16): 29352-29364, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36299111

RESUMO

In this follow up of our previous work on bio-inspired photonics [Opt. Express28, 25007 (2020)10.1364/OE.399505], we present a detailed comparison between the absorption characteristics of hexagonal and square lattice oriented bi-layered photonic structures designed based on the morphology of Coscinodiscus diatom. It is well established that single layers of square lattice-based systems offer better light absorption characteristics than their hexagonal counterparts. However this study shows that superior performances are obtained with hexagonal lattices when bi-layered photonic structures mimicking Coscinodiscus diatom are designed. The finite difference time domain and effective medium approximation based numerical analysis of this work show that bi-layered structures containing hexagonal lattices exhibit tunable, near-perfect (∼95%) absorptance at around 426 nm wavelength up to about 60° angle of incidence, whereas for square lattice the absorptance goes below 85% (65%) for TM (TE) polarization. Moreover, depending on whether light is being incident onto smaller or larger pores of the bi-layered system, peak absorptance for hexagonal lattices is obtained to be nearly 4 times higher than the results obtained for the equivalent square lattices. Such characteristics make the hexagonal lattice-based structures more suitable for bi-facial light absorption related applications.

13.
Am J Primatol ; 84(1): e23345, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34783056

RESUMO

Rhesus macaques are considered an important reservoir of different gastrointestinal (GI) zoonotic parasites affecting livestock and humans. Loads of GI parasites in the free-ranging rhesus macaques living in close proximity to communities in Bangladesh are still unknown. To estimate the prevalence and diversity of zoonotic GI parasites in rhesus macaques of Bangladesh, a total of 182 freshly voided fecal samples were collected from macaques living in rural (N = 67), peri-urban (N = 57), urban (N = 28), and Safari park (N = 30) between October 2015 and December 2016. All samples were tested by direct smear, sedimentation, flotation, and the McMaster techniques. A total of fourteen different taxa of GI parasites were detected, revealing an overall prevalence of 54.4% (n = 99; 95% confidence interval [CI]: 46.9-61.8). The prevalence of GI parasites was found to be significantly correlated with the mean parasitic taxa per individual in a group (r = 0.90; p = 0.002). The multivariable logistic regression analysis showed that the overall prevalence of GI parasites in macaques was significantly higher in those inhabiting rural areas (62.69%; odds ratio [OR]: 7.22; p = 0.001) and in macaques with interactions with other animals (60.98%; OR: 5.49; p = 0.005). Our results also indicated that the prevalence of Strongyloides spp. and Balantidium coli infections varied significantly between land gradients. Our results also indicate that macaques frequently visit human settlements for food and are found interacting with domestic animals. In conclusion, the high prevalence of zoonotic GI parasite infection in rhesus macaques found in our study may pose a significant public health risk to communities, particularly in rural areas of Bangladesh. Health promotion to at-risk communities focusing on limiting contact with rhesus macaques is necessary to mitigate potential zoonotic transmission.


Assuntos
Enteropatias Parasitárias , Parasitos , Animais , Bangladesh/epidemiologia , Fezes , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/veterinária , Macaca mulatta , Prevalência
14.
Sensors (Basel) ; 22(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080971

RESUMO

The correlations between smartphone sensors, algorithms, and relevant techniques are major components facilitating indoor localization and tracking in the absence of communication and localization standards. A major research gap can be noted in terms of explaining the connections between these components to clarify the impacts and issues of models meant for indoor localization and tracking. In this paper, we comprehensively study the smartphone sensors, algorithms, and techniques that can support indoor localization and tracking without the need for any additional hardware or specific infrastructure. Reviews and comparisons detail the strengths and limitations of each component, following which we propose a handheld-device-based indoor localization with zero infrastructure (HDIZI) approach to connect the abovementioned components in a balanced manner. The sensors are the input source, while the algorithms are used as engines in an optimal manner, in order to produce a robust localizing and tracking model without requiring any further infrastructure. The proposed framework makes indoor and outdoor navigation more user-friendly, and is cost-effective for researchers working with embedded sensors in handheld devices, enabling technologies for Industry 4.0 and beyond. We conducted experiments using data collected from two different sites with five smartphones as an initial work. The data were sampled at 10 Hz for a duration of five seconds at fixed locations; furthermore, data were also collected while moving, allowing for analysis based on user stepping behavior and speed across multiple paths. We leveraged the capabilities of smartphones, through efficient implementation and the optimal integration of algorithms, in order to overcome the inherent limitations. Hence, the proposed HDIZI is expected to outperform approaches proposed in previous studies, helping researchers to deal with sensors for the purposes of indoor navigation-in terms of either positioning or tracking-for use in various fields, such as healthcare, transportation, environmental monitoring, or disaster situations.


Assuntos
Algoritmos , Smartphone , Computadores , Meios de Transporte
15.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36499359

RESUMO

Direct alcohol fuel cells are deemed as green and sustainable energy resources; however, CO-poisoning of Pt-based catalysts is a critical barrier to their commercialization. Thus, investigation of the electrochemical CO oxidation activity (COOxid) of Pt-based catalyst over pH ranges as a function of Pt-shape is necessary and is not yet reported. Herein, porous Pt nanodendrites (Pt NDs) were synthesized via the ultrasonic irradiation method, and its CO oxidation performance was benchmarked in different electrolytes relative to 1-D Pt chains nanostructure (Pt NCs) and commercial Pt/C catalyst under the same condition. This is a trial to confirm the effect of the size and shape of Pt as well as the pH of electrolytes on the COOxid. The COOxid activity and durability of Pt NDs are substantially superior to Pt NCs and Pt/C in HClO4, KOH, and NaHCO3 electrolytes, respectively, owing to the porous branched structure with a high surface area, which maximizes Pt utilization. Notably, the COOxid performance of Pt NPs in HClO4 is higher than that in NaHCO3, and KOH under the same reaction conditions. This study may open the way for understanding the COOxid activities of Pt-based catalysts and avoiding CO-poisoning in fuel cells.


Assuntos
Medicina , Nanoestruturas , Eletrólitos , Oxirredução , Tomografia por Emissão de Pósitrons
16.
Gastroenterology ; 159(1): 169-182.e8, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32169428

RESUMO

BACKGROUND & AIMS: Helicobacter pylori induces strong inflammatory responses that are directed at clearing the infection, but if not controlled, these responses can be harmful to the host. We investigated the immune-regulatory effects of the innate immune molecule, nucleotide-binding oligomerization domain-like receptors (NLR) family CARD domain-containing 5 (NLRC5), in patients and mice with Helicobacter infection. METHODS: We obtained gastric biopsies from 30 patients in Australia. We performed studies with mice that lack NLRC5 in the myeloid linage (Nlrc5møKO) and mice without Nlrc5 gene disruption (controls). Some mice were gavaged with H pylori SS1 or Helicobacter felis; 3 months later, stomachs, spleens, and sera were collected, along with macrophages derived from bone marrow. Human and mouse gastric tissues and mouse macrophages were analyzed by histology, immunohistochemistry, immunoblots, and quantitative polymerase chain reaction. THP-1 cells (human macrophages, controls) and NLRC5-/- THP-1 cells (generated by CRISPR-Cas9 gene editing) were incubated with Helicobacter and gene expression and production of cytokines were analyzed. RESULTS: Levels of NLRC5 messenger RNA were significantly increased in gastric tissues from patients with H pylori infection, compared with patients without infection (P < .01), and correlated with gastritis severity (P < .05). H pylori bacteria induced significantly higher levels of chemokine and cytokine production by NLRC5-/- THP-1 macrophages than by control THP-1 cells (P < .05). After 3 months of infection with H felis, Nlrc5mø-KO mice developed gastric hyperplasia (P < .0001), splenomegaly (P < .0001), and increased serum antibody titers (P < .01), whereas control mice did not. Nlrc5mø-KO mice with chronic H felis infection had increased numbers of gastric B-cell follicles expressing CD19 (P < .0001); these follicles had features of mucosa-associated lymphoid tissue lymphoma. We identified B-cell-activating factor as a protein that promoted B-cell hyperproliferation in Nlrc5mø-KO mice. CONCLUSIONS: NLRC5 is a negative regulator of gastric inflammation and mucosal lymphoid formation in response to Helicobacter infection. Aberrant NLRC5 signaling in macrophages can promote B-cell lymphomagenesis during chronic Helicobacter infection.


Assuntos
Infecções por Helicobacter/complicações , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfoma de Zona Marginal Tipo Células B/imunologia , Neoplasias Gástricas/imunologia , Animais , Linfócitos B/imunologia , Biópsia , Proliferação de Células , Modelos Animais de Doenças , Feminino , Mucosa Gástrica/imunologia , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica/imunologia , Técnicas de Inativação de Genes , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter felis/imunologia , Helicobacter pylori/imunologia , Humanos , Hiperplasia/imunologia , Hiperplasia/microbiologia , Imunidade Inata , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Tecido Linfoide/imunologia , Tecido Linfoide/microbiologia , Tecido Linfoide/patologia , Linfoma de Zona Marginal Tipo Células B/microbiologia , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Camundongos , Camundongos Knockout , Transdução de Sinais/imunologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Células THP-1
17.
Opt Express ; 29(16): 25745-25761, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614897

RESUMO

In spite of tremendous advancements in modern diagnostics, there is a dire need for reliable, label-free detection of highly contagious pathogens like viruses. In view of the limitations of existing diagnostic techniques, the present theoretical study proposes a novel scheme of detecting virus-like particles employing whispering gallery and quasi-whispering gallery resonant modes of a composite optical system. Whereas whispering gallery mode (WGM) resonators are conventionally realized using micro-disk, -ring, -toroid or spherical structures, the present study utilizes a rotationally symmetric array of silicon nanowires which offers higher sensitivity compared to the conventional WGM resonator while detecting virus-like particles. Notwithstanding the relatively low quality factor of the system, the underlying multiple-scattering mediated photon entrapment, coupled with peripheral total-internal reflection, results in high fidelity of the system against low signal-to-noise ratio. Finite difference time domain based numerical analysis has been performed to correlate resonant modes of the array with spatial location of the virus. The correlation has been subsequently utilized for statistical analysis of simulated test cases. Assuming detection to be limited by resolution of the measurement system, results of the analysis suggest that for only about 5% of the simulate test cases the resonant wavelength shift lies within the minimum detection range of 0.001-0.01 nm. For a single virus of 160 nm diameter, more than 8 nm shift of the resonant mode and nearly 100% change of quality factor are attained with the proposed nanowire array based photonic structure.


Assuntos
Modelos Teóricos , Nanofios , Dispositivos Ópticos , Silício , Vírion/isolamento & purificação , Óptica e Fotônica/métodos , Razão Sinal-Ruído , Vírion/ultraestrutura
18.
Trends Food Sci Technol ; 111: 141-150, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33746363

RESUMO

BACKGROUND: The agricultural food products industry in Bangladesh depends on utilizing antimicrobials indiscriminately as growth promoters and for controlling infectious diseases. Thus, there is always a risk of antimicrobial agent accumulation in food sources that originate from agricultural production. METHODS: In the present study, we collected data from published articles between January, 2013 and December, 2019 on antimicrobial residues in human food sources such as meat, milk, eggs, and fishes. RESULTS: Liver contained the highest percentage of antimicrobial residues (74%; 95% CI: 59.66-85.37) against the in vitro enteric pathogen Escherichia coli in layer chickens. Similar results were demonstrated in liver (68%; 95% CI: 53.30-80.48) and kidney (66%, 95% CI: 51.23-78.79) of layer chickens against Bacillus cereus and Bacillus subtilis. Amongst all antibiotics, the highest concentrations of ciprofloxacin were detected in kidney (48.57%; 95% CI: 31.38-66.01), followed by liver (47.56; 95% CI: 40.88-54.30) of broiler chickens. Ciprofloxacin was also present in liver (46.15%; 95% CI: 33.70-58.96) of layer chickens. The percentage of ciprofloxacin in thigh and breast meat in broiler bird were 41.54% (95% CI: 34.54-48.79) and 37.95% (95% CI: 31.11-45.15) respectively. Enrofloxacin was the second most dominant antimicrobial agent and was present in the liver of both types of poultry (Broiler and Layer chickens: 41.54%; 95% CI: 29.44-54.4 and 437.33%; 95% CI: 30.99-44.01). The prevalence rates of enrofloxacin in thigh and breast meat of broiler chickens were 24.10% (95% CI: 18.28-30.73) and 20.51% (95% CI: 15.08-26.87), respectively. Tetracycline, a commonly used antibiotic in livestock, was present in the liver (49.23%; 95% CI: 36.60-61.93) of layer chickens. In case of aquaculture food products, the highest amount of amoxicillin (683.2 mg/kg) was detected in Tilapia fish (Oreochromis niloticus), followed by 584.4 mg/kg in climbing perch (Anabas testudineus) and 555.6 mg/kg in Rui fish (Labeo rohita). Among the five types of fishes, Rui fish (0.000515 mg/kg) contained the highest concentrations of chloramphenicol antibiotic residues. CONCLUSIONS: The presence of antimicrobial residues in meat, milk, egg, and fish is a serious public health threat due to the potential induction of antimicrobial resistance. It can negatively impact the food supply chain, especially with the current strain that it is already facing with the current COVID-19 pandemic. The findings of the present study highlight the ongoing risk of residual antimicrobial agents in food of animal origin in Bangladesh and countries with similar practices. This can draw the attention of public health officials to propose plans to mitigate or stop this practice.

19.
ScientificWorldJournal ; 2021: 7533119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34924861

RESUMO

Bangladesh is rich in wetland biodiversity with aquatic plants, fishes, and birds. Mohanganj Upazila is known as the capital of lower Bangladesh. The present study focuses on the changes of land use and land cover (LULC) with a diversity of species that are being least concerned (LC), vulnerable (VU), and endangered (EN). Over the last two decades, the wetland species of Mohanganj were gradually declined. Our results showed that 19 fish, 4 aquatic plants, and 7 bird species were LC in 2015. Among the fish and aquatic plant species, 6 fish species (Wallago attu, Ompok pabda, Channa punctate, Chitala chitala, Salmostoma phulo, and Corica soborna) and 2 aquatic plant species (Nymphaea nouchali and Nymphaea lotus) were VU during the dry and rainy season of 2017 and 2019, respectively. In the dry season of 2019, 4 fish species (W. attu, O. pabda, C. punctate, and Ch. chitala), 2 aquatic plant species (N. nouchali and N. lotus), and 7 bird species (Anas platyrhynchos, Ardeola grayii, Gyps bengalensis, Alcedo atthis, Phalacrocorax fuscicollis, Porphyrio porphyria, and Larus ridibundus) were EN. Among the species, W. attu, N. nouchaii, G. bengalensis, P. porphyria, and L. ridibundus were extremely endangered categories. Changes in LULC, the establishment of settlements for the increasing population, indiscriminate use of pesticides, environmental pollutions, and climate change are the potential reasons for declining trends of wetland biodiversity. Stern actions on land use policy, expansion of organic agriculture, bioremediation of industrial effluents, and adoption of sustainable environmental policies should be taken by the Government of Bangladesh for immediate conservation of wetland biodiversity.


Assuntos
Biodiversidade , Aves/classificação , Peixes/classificação , Plantas/classificação , Áreas Alagadas , Animais , Espécies em Perigo de Extinção
20.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34250503

RESUMO

LC-MS analysis of plant growth-promoting rhizobacterium (PGPR) Bacillus velezensis AP203 supernatants indicated the presence of nematode-inhibiting compounds that increased in abundance when B. velezensis AP203 was grown on orange peel. Meloidogyne incognita J2 were incubated with B. velezensis AP203 spores and orange peel, spores alone, orange peel alone, or with a non-inoculated control, and the combination of B. velezensis AP203 with orange peel resulted in 94% mortality of M. incognita juveniles (p ≤ 0.05). The J2 mortality rate for B. velezensis alone was 53%, compared to 59% mortality with orange peel, and the non-inoculated control exhibited 7% mortality. When tested on soybeans raised in a greenhouse, it was observed that when grown in the presence of orange peel, B. velezensis AP203 culture broth, cell suspension or supernatant reduced the numbers of M. incognita eggs per g of root at 45 days after planting (DAP) compared to inoculated controls in soybean and cotton (p ≤ 0.05). Likewise, soybean root length and fresh root weight significantly increased after inoculation with B. velezensis AP203 amended with orange peel. In cotton, shoot and root length significantly increased after inoculation with cell pellets of B. velezensis AP203 amended with orange peel compared to the M. incognita inoculated control. These data indicate that B. velezensis AP203 responds to growth on pectin-rich orange peel by production of biologically active secondary metabolites that can promote plant growth and inhibit root-knot nematode viability.

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