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1.
ACS Biomater Sci Eng ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656158

RESUMO

Given the worldwide problem posed by enteric pathogens, the discovery of safe and efficient intestinal adjuvants combined with novel antigen delivery techniques is essential to the design of mucosal vaccines. In this work, we designed poly (lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs) to codeliver all-trans retinoic acid (atRA), novel antigens, and CpG. To address the insolubility of the intestinal adjuvant atRA, we utilized PLGA to encapsulate atRA and form a "nanocapsid" with polydopamine. By leveraging polydopamine, we adsorbed the water-soluble antigens and the TLR9 agonist CpG onto the NPs' surface, resulting in the pathogen-mimicking PLPCa NPs. In this study, the novel fusion protein (HBf), consisting of the Mycobacterium avium subspecies paratuberculosis antigens HBHA, Ag85B, and Bfra, was coloaded onto the NPs. In vitro, PLPCa NPs were shown to promote the activation and maturation of bone marrow-derived dendritic cells. Additionally, we found that PLPCa NPs created an immune-rich microenvironment at the injection site following intramuscular administration. From the results, the PLPCa NPs induced strong IgA levels in the gut in addition to enhancing powerful systemic immune responses. Consequently, significant declines in the bacterial burden and inflammatory score were noted in PLPCa NPs-treated mice. In summary, PLPCa can serve as a novel and safe vaccine delivery platform against gut pathogens, such as paratuberculosis, capable of activating both systemic and intestinal immunity.

2.
Int J Parasitol Parasites Wildl ; 23: 100925, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38560661

RESUMO

Red foxes (Vulpes vulpes) have been recognized as natural reservoirs for multiple pathogens and a source of infection for domestic animals, wildlife and humans. To date, no reports are available on the Bartonella rochalimae and Hepatozoon canis infection in red foxes from China. In 2018-2022, a total of 16 red foxes were sampled in two counties and a city in Xinjiang Uygur Autonomous Region (XUAR) in northwest China. Subsequently analyzed by DNA extraction amplified by polymerase chain reaction (PCR). In the present study, based on nucleotide sequence and phylogenetic tree analyses, B. rochalimae and H. canis were molecularly identified in red foxes. Our findings provide the first molecular evidence of B. rochalimae and H. canis in red foxes from China.

3.
J Wildl Dis ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38659240

RESUMO

ANAPLASMA BOVIS: (1), Bartonella krasnovii (3), and Bartonella sp. (17) were detected in 80 Libyan jirds (Meriones libycus) from China. These findings extend the known host and geographic ranges of these pathogens, with neither A. bovis nor B. krasnovii previously confirmed in Libyan jirds.

4.
Int J Parasitol Parasites Wildl ; 23: 100923, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38524248

RESUMO

Eurasian lynx (Lynx lynx) is widely distributed in various habitats in Asia and Europe, and it may harbor multiple pathogens. Currently, the information on protozoan infection in Eurasian lynx is scarce. In this study, we performed nested polymerase chain reaction (nPCR) analysis to detect intestinal protozoan infection in three dead Eurasian lynxes, in northwestern China. Three dead Eurasian lynxes, an adult female (#1), an adult male (#2), and a cub male (#3), were sampled in West Junggar Mountain, the northwestern region of Xinjiang Uyghur Autonomous Region. The intestine samples were analyzed using nPCR. We used primers targeting the cytochrome C oxidase subunit I gene (COI) for detection of Sarcocystis and Eimeria species and targeting the small subunit 18 S ribosomal RNA gene (18S rRNA) for detection of Cystoisospora species. The nPCR-positive products were sequenced, aligned, and phylogenetically analyzed. Three intestinal protozoa, Sarcocystis albifronsi, Eimeria alpacae, and Cystoisospora felis, were found in three Eurasian lynxes. The intestine sample of Eurasian lynx #2 was detected with S. albifronsi and E. alpacae. In addition, C. felis was only found in the intestine sample of Eurasian lynx #3. To the best of our knowledge, S. albifronsi and E. alpacae were detected in Eurasian lynx for the first time. In addition, C. felis was firstly found in Eurasian lynx in China. These findings extend our knowledge of the geographical distribution and host range of intestinal protozoa.

5.
Parasit Vectors ; 17(1): 152, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519971

RESUMO

BACKGROUND: In the family Trypanosomatidae, the genus Trypanosoma contains protozoan parasites that infect a diverse range of hosts, including humans, domestic animals, and wildlife. Wild rodents, as natural reservoir hosts of various pathogens, play an important role in the evolution and emergence of Trypanosomatidae. To date, no reports are available on the trypanosomatid infection of pikas (Lagomorpha: Ochotonidae). METHODS: In this study, Mongolian pikas and their fleas were sampled at the China-Mongolia border, northwestern China. The samples were analyzed with polymerase chain reaction (PCR) and sequencing for the presence of Trypanosomatidae on the basis of both the 18S ribosomal RNA (18S rRNA) gene and the glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene. The morphology of trypomastigotes was also observed in peripheral blood smears by microscopy. RESULTS: Molecular and phylogenetic analyses revealed a new genotype of the Trypanosoma lewisi clade that was found both in pika blood and flea samples. This genotype, which probably represents a new species, was provisionally designated as "Trypanosoma sp. pika". In addition, a novel genotype belonging to the genus Blechomonas of Trypanosomatidae was detected in fleas. On the basis of its molecular and phylogenetic properties, this genotype was named Blechomonas luni-like, because it was shown to be the closest related to B. luni compared with other flea-associated trypanosomatids. CONCLUSIONS: To the best of our knowledge, this is the first study to report any trypanosomatid species in Mongolian pikas and their fleas. Further studies are needed to investigate the epidemiology of these protozoan parasites, as well as to evaluate their pathogenicity for humans or domestic animals.


Assuntos
Lagomorpha , Sifonápteros , Trypanosoma , Trypanosomatina , Animais , Humanos , Lagomorpha/parasitologia , Sifonápteros/parasitologia , Filogenia , China/epidemiologia , Trypanosoma/genética , Trypanosomatina/genética , Animais Domésticos , Gerbillinae
6.
Sci Rep ; 14(1): 6003, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472493

RESUMO

To investigate the efficacy and safety of drug-eluting bead-transarterial chemoembolization (DEB-TACE) combined with systemic chemotherapy in HR+/Her2- locally advanced breast cancer (LABC) patients. A controlled study was conducted on LABC patients treated at Jianyang People's Hospital and the First Affiliated Hospital of Chengdu Medical College from December 2020 to June 2022. The patients were randomly divided into the experimental group and the control group. The experimental group received DEB-TACE combined with the TAC regimen (175 mg/m2 paclitaxel-loaded albumin, 50 mg/m2 Doxorubicin, and 500 mg/m2 cyclophosphamide), while the control group received the TAC regimen intravenously. The therapeutic efficacy was evaluated using the mRECIST criteria. Statistical analysis was performed using SPSS 22.0 software, and baseline characteristics, overall response rate (ORR), pathological complete response (PCR), adverse reactions, and complications were compared between the two groups using paired t-test and chi-square test. A total of 60 patients were included, with 30 patients in the experimental group (50%) and 30 patients in the control group (50%). After the first treatment, the ORR was 90% in the experimental group and 60% in the control group (P < 0.05). The overall ORR was 100% in the experimental group and 83% in the control group (P < 0.05). PCR was achieved in 14 patients (47%) in the experimental group and 4 patients (13%) in the control group. The main adverse reactions in the experimental group were skin blistering, pigmentation, and pain. There was no statistically significant difference in vomiting and grade II or above bone marrow suppression between the two groups. No grade III or above adverse events occurred in either group. The comparison of tumor shrinkage between the two groups was P = 0.051, and axillary lymph node shrinkage was P < 0.05. The use of drug-eluting beads in combination with neoadjuvant chemotherapy is a feasible and safe treatment option for locally advanced breast cancer patients.


Assuntos
Neoplasias da Mama , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Doxorrubicina
7.
Exp Appl Acarol ; 92(3): 547-554, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38386133

RESUMO

Forty-five tick species have been recorded in Kazakhstan. However, their genetic diversity and evolutionary relationships, particularly when compared to ticks in neighbouring countries, remain unclear. In the present study, 148 mitochondrial cytochrome c oxidase subunit I (COI) sequence data from our laboratory and NCBI (National Center for Biotechnology Information; https://www.ncbi.nlm.nih.gov/ ) data were used to address this knowledge gap. Phylogenetic analyses showed that i) Hyalomma anatolicum anatolicum (Koch, 1844) ticks from Jambyl Oblast (southeastern Kazakhstan) and Gansu Province (northwestern China) constituted a newly deviated clade; and ii) Dermacentor reticulatus (Fabricius, 1974) ticks from South Kazakhstan Oblast were closer to those in Romania and Turkey. The network diagram of haplotypes showed that i) the H-1 and H-2 haplotypes of Dermacentor marginatus (Sulzer, 1776) ticks from Zhetisu and Almaty were all newly evolved; and ii) the H-3 haplotypes of Haemaphysalis erinacei (Pavesi, 1884) from Almaty Oblast and Xinjiang Uygur Autonomous Region (northwestern China) were evolved from the H-1 haplotype from Italy. In the future, more COI data from different tick species, especially from Kazakhstan and neighbouring countries, should be employed in the field of tick DNA barcoding.


Assuntos
Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons , Variação Genética , Ixodidae , Filogenia , Animais , Cazaquistão , Ixodidae/genética , Ixodidae/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Haplótipos , Proteínas de Artrópodes/genética
8.
Acta Parasitol ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418764

RESUMO

INTRODUCTION: To date, a total of 2574 validated flea species have been discovered. Vermipsyllidae is a family of fleas that comprises at least eight species. Vermipsylla is a genus of the family Vermipsyllidae within the order Siphonaptera of fleas. Here a novel Vermipsylla species was described, and rickettsial agent was also detected in it. METHODS: A total of 128 fleas were collected directly from 260 pastured sheep in China. Of these, eight representative fleas (four males and four females) were identified by key morphological features. Meanwhile, 120 flea DNAs, including six flea samples for molecular taxonomy, were subjected to Rickettsia spp. DNA detection. The molecular identity of fleas was determined by amplification and sequenmce analysis of four genetic markers (the 28S rDNA genes, the 18S rDNA genes, the mitochondrial cytochrome c oxidase subunit I and subunit II). In addition, five Rickettsia-specific gene fragments were used to identify the species of the rickettsial agents. The amplified products were sequenced and phylogenetically analyzed. RESULTS: The morphological characteristics of the flea species identified in this study were similar to Vermipsylla alakurt, but presented difference in hair number of the metepimeron, the third tergum, the genitals and the tibiae of hind leg. The 18S rDNA, 28S rDNA and COII genetic markers from fleas showed the highest identity to those of V. alakurt, shared 98.45% (954/969), 95.81% (892/931) and 85.86% (571/665) similarities, respectively. However, the COI sequence showed the highest identity to that of Dorcadia ioffi with 88.48% (576/651) similarity. Rickettsia raoutii tested positive in 14.17% (17/120) flea DNA samples. CONCLUSION: Our study reports the detection of R. raoultii in V. alakurt-like fleas infesting sheep in China.

9.
Parasit Vectors ; 17(1): 55, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326828

RESUMO

BACKGROUND: Rodents play an important role in the life cycle of ixodid and argasid ticks, particularly as hosts of larvae and nymphs. The great gerbil (Rhombomys opimus), the preferred prey item of several carnivores (e.g. the red fox and marbled polecat), is the dominant rodent species in the Gurbantunggut Desert in northwestern China. The aim of this study was to investigate tick species associated with different hosts in the habitat of great gerbils, including wildlife and livestock. METHODS: During 2018-2023, ticks were removed from 326 great gerbils, two red foxes (Vulpes vulpes), three marbled polecats (Vormela peregusna), 35 pastured sheep (Ovis aries), and one long-eared desert hedgehog (Hemiechinus auritus) in the Gurbantunggut Desert. Ticks were identified according to standard morphological keys. Then, they were further analyzed by molecular and phylogenic methods based on two mitochondrial markers, 16S rDNA and cytochrome c oxidase subunit I (COI) genes. RESULTS: A total of 889 ticks were collected, representing five species. These included Hyalomma asiaticum (n = 425: 24 larvae, 79 nymphs and 322 adults), Rhipicephalus turanicus (n = 153: 2 nymphs and 151 adults), Haemaphysalis erinacei (n = 298: 4 larvae, 7 nymphs and 287 adults), Ixodes acuminatus (n = 7: 4 nymphs and 3 adults) and Ornithodoros tartakovskyi (6 adults). Based on COI sequences, molecular and phylogenetic analyses showed that (i) I. acuminatus from great gerbils and marbled polecats clustered with I. acuminatus reported from Europe; (ii) O. tartakovskyi found in northwestern China belonged to an independent clade; (iii) Hy. asiaticum, R. turanicus and Ha. erinacei had 100% sequence identities to conspecific ticks sampled previously in China. CONCLUSIONS: The great gerbil is an important host for the developmental stages of I. acuminatus, O. tartakovskyi, Ha. erinacei, Hy. asiaticum and R. turanicus, thus supporting the life cycle of several tick species which, as adults, parasitize predators (red fox and marble polecat) as well as pastured sheep and hedgehogs in the Gurbantunggut Desert. Ixodes acuminatus and O. tartakovskyi were found for the first time on great gerbil and marbled polecat, respectively.


Assuntos
Ixodes , Ixodidae , Mustelidae , Doenças dos Roedores , Doenças dos Ovinos , Infestações por Carrapato , Animais , Ovinos , Gerbillinae , Filogenia , Raposas , Animais Selvagens , Ninfa , Larva , Infestações por Carrapato/veterinária
10.
Ticks Tick Borne Dis ; 14(6): 102238, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37722147

RESUMO

Infections with spotted fever group rickettsiae represent a worldwide health problem, characterized by persistent high fever, headache, and rash in humans, domestic animals, and wildlife. To date, the occurrence of Rickettsia species in hard ticks has not been thoroughly studied, especially in eastern and southern Kazakhstan. A total of 1,245 adult ticks, comprising 734 Dermacentor marginatus, 219 Hyalomma scupense, 144 Hyalomma asiaticum, 84 Hyalomma marginatum, 48 Rhipicephalus turanicus, and 16 Haemaphysalis erinacei, collected from East Kazakhstan, Abay, Jetsu, Almaty, Jambyl, South Kazakhstan and Qyzylorda oblasts of Kazakhstan, were used to screen rickettsial agents using molecular methods. Rickettsia raoultii, Rickettsia slovaca, Rickettsia aeschlimannii and Rickettsia heilongjiangensis were identified using sequencing, and 31.5% (392/1245) of ticks carried rickettsial agents. The difference in the natural landscapes explains the variety of the collected ticks and expands our knowledge of Rickettsia species and their geographical distribution in Kazakhstan. To the best of our knowledge, this study reports the first finding of R. heilongjiangensis in Kazakhstan.


Assuntos
Ixodidae , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Adulto , Animais , Humanos , Cazaquistão/epidemiologia , Rickettsiales
11.
Vet Clin Pathol ; 52(4): 732-736, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37723640

RESUMO

BACKGROUND: The Himalayan marmot (Marmota himalayana) plays a reservoir role in the epidemiology of brucellosis. However, the changes in blood biochemical parameters are still unclear in Brucella-seropositive marmots. OBJECTIVES: The present study was designed to explore the hematologic and biochemical variable changes in Brucella-seropositive marmots. METHODS: Blood samples were collected from the dorsalis pedis vein of Himalayan marmots (24 Brucella-seropositive marmots and 24 Brucella-free marmots). Ten hematologic and 10 serum biochemical variable examinations were performed and analyzed. RESULTS: Our results showed that leukocyte, platelet, neutrophil, and lymphocyte counts significantly increased, while the level of carbon dioxide combining power decreased in Brucella-infected marmots. These findings indicate that Brucella triggers an immune response in Himalayan marmots. CONCLUSIONS: This study provides a preliminary investigation of the changes in blood biochemical analytes in Brucella-infected marmots. The interaction between Brucella infection and blood biochemical indices in Himalayan marmots should be further explored.


Assuntos
Brucella , Marmota , Animais , Marmota/fisiologia
12.
J Neurotrauma ; 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37265124

RESUMO

The early stages of brain injury can induce acute liver injury, which can be recovered in the short term. Continued medication treatment during hospitalization for brain injury alleviates the prognosis and contributes to a high incidence of drug-induced liver injury (DILI). We hypothesize that there is an interaction between changes in the hepatic environment after brain injury and liver injury produced by intensive drug administration, leading to an upregulation of the organism's sensitivity to DILI. In this study, mice models of TBI were established by controlled cortical impact and models of DILI were constructed by acetaminophen (APAP). All mice were divided into four groups: Sham, TBI, APAP, and TBI+APAP, and related liver injury indicators in liver and serum were detected by Western blot, RT-PCR, and immunohistochemical staining. The results suggested that liver injury induced in the early stages of brain injury recovered in three days, but this state could still significantly aggravate DILI, represented by higher liver enzymes (AST and ALT), oxidative stress (increase in malondialdehyde concentration and deregulation of glutathione and superoxide dismutase activities), inflammatory response (activation of HMGB1/TLR4/NF-κB signaling pathway, and increased mRNA and protein levels of pro-inflammatory cytokines including TNF-α, IL-6, and IL-1ß), and apoptosis (TUNEL assay, upregulation of Bax protein and deregulation of Bcl-2 protein). In summary, our results suggested that traumatic brain injury is a potential susceptibility factor for DILI and exacerbates DILI.

13.
Front Plant Sci ; 14: 1090711, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36890903

RESUMO

Long non-coding RNAs (lncRNAs) serve as crucial regulators in plant response to various diseases, while none have been systematically identified and characterized in response to citrus Huanglongbing (HLB) caused by Candidatus Liberibacter asiaticus (CLas) bacteria. Here, we comprehensively investigated the transcriptional and regulatory dynamics of the lncRNAs in response to CLas. Samples were collected from leaf midribs of CLas- and mock-inoculated HLB-tolerant rough lemon (Citrus jambhiri) and HLB-sensitive sweet orange (C. sinensis) at week 0, 7, 17, and 34 following inoculation using CLas+ budwood of three biological replicates in the greenhouse. A total of 8,742 lncRNAs, including 2,529 novel lncRNAs, were identified from RNA-seq data with rRNA-removed from strand-specific libraries. Genomic variation analyses of conserved lncRNAs from 38 citrus accessions showed that 26 single nucleotide polymorphisms (SNPs) were significantly correlated with HLB. In addition, lncRNA-mRNA weighted gene co-expression network analysis (WGCNA) showed a significant module correlated with CLas-inoculation in rough lemon. Notably, the most significant LNC_28805 and multiple co-expressed genes related to plant defense in the module were targeted by miRNA5021, suggesting that LNC28805 might compete with endogenous miR5021 to maintain the homeostasis of immune gene expression levels. Candidate WRKY33 and SYP121 genes targeted by miRNA5021 were identified as two key hub genes interacting with bacteria pathogen response genes based on the prediction of protein-protein interaction (PPI) network. These two genes were also found within HLB-associated QTL in linkage group 6. Overall, our findings provide a reference for a better understanding of the role of lncRNAs involved in citrus HLB regulation.

14.
Microbiol Spectr ; : e0343122, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36847491

RESUMO

Accumulating evidence indicates that antibodies can protect against some intracellular pathogens. Mycobacterium bovis is an intracellular bacterium, and its cell wall (CW) is essential for its virulence and survival. However, the questions of whether antibodies play a protective role in immunity against M. bovis infection and what effects antibodies specific to the CW of M. bovis have still remain unclear. Here, we report that antibodies targeting the CW of an isolated pathogenic M. bovis strain and that of an attenuated bacillus Calmette-Guérin (BCG) strain could induce protection against virulent M. bovis infection in vitro and in vivo. Further research found that the antibody-induced protection was mainly achieved by promoting Fc gamma receptor (FcγR)-mediated phagocytosis, inhibiting bacterial intracellular growth, and enhancing the fusion of phagosomes and lysosomes, and it also depended on T cells for its efficacy. Additionally, we analyzed and characterized the B-cell receptor (BCR) repertoires of CW-immunized mice via next-generation sequencing. CW immunization stimulated BCR changes in the complementarity determining region 3 (CDR3) isotype distribution, gene usage, and somatic hypermutation. Overall, our study validates the idea that antibodies targeting the CW induce protection against virulent M. bovis infection. This study highlights the importance of antibodies targeting the CW in the defense against tuberculosis. IMPORTANCE M. bovis is the causative agent of animal tuberculosis (TB) and human TB. Research on M. bovis is of great public health significance. Currently, TB vaccines are mainly aimed at eliciting protection by enhancement of cell-mediated immunity, and there are few studies on protective antibodies. This is the first report of protective antibodies against M. bovis infection, and the antibodies had both preventive and even therapeutic effects in an M. bovis infection mouse model. Additionally, we reveal the relationship between CDR3 gene diversity and the immune characteristics of the antibodies. These results will provide valuable advice for the rational development of TB vaccines.

15.
J Wildl Dis ; 59(1): 138-142, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656283

RESUMO

Tacheng tick virus 1 (TcTV-1) and Songling virus (SGLV) were originally found in human patients in China who had had tick bites. Tamdy virus (TAMV) was detected for the first time in a tick-infested person from Kyrgyzstan in 1973. In this study, 276 great gerbils (Rhombomys opimus) were collected in Xinjiang Uygur Autonomous Region in northwestern China. The total RNA of individual spleen samples was extracted, and the viral L segments of TcTV-1, SGLV, and TAMV were detected by nested reverse transcription PCR. Overall, 2.9% (8/276) and 2.2% (6/276) of spleen samples tested positive to the viral L segments for TcTV-1 and SGLV, respectively; TAMV was not detected in any samples. The SGLV from the great gerbils shared 93.7% (236/252 nucleotide [nt]) and 94.0% (78/83 amino acid [aa]) identities to SGLV detected in patients infected with SGLV in northeastern China. The TcTV-1 in great gerbils was closest to TcTV-1 from a patient in China, with 98.5% (797/809 nt) and 98.9% (265/268 aa) sequence identities. This is the first molecular evidence for the presence of TcTV-1 and SGLV in great gerbils. High genetic diversity in SGLV was observed among geographical locations. Multiregion surveillance of Tamdy orthonairoviruses in more wildlife species is necessary.


Assuntos
Doenças dos Roedores , Carrapatos , Viroses , Vírus , Humanos , Animais , Gerbillinae , Viroses/veterinária , China/epidemiologia
17.
Micromachines (Basel) ; 13(12)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36557549

RESUMO

This paper presents a piezoresistive differential pressure sensor based on a silicon-on-insulator (SOI) structure for low pressure detection from 0 to 30 kPa. In the design phase, the stress distribution on the sensing membrane surface is simulated, and the doping concentration and geometry of the piezoresistor are evaluated. By optimizing the process, the realization of the pressure sensing diaphragm with a controllable thickness is achieved, and good ohmic contact is ensured. To obtain higher sensitivity and high temperature stability, an SOI structure with a 1.5 µm ultra-thin monocrystalline silicon layer is used in device manufacturing. The device diaphragm size is 700 µm × 700 µm × 2.1 µm. The experimental results show that the fabricated piezoresistive pressure sensor has a high sensitivity of 2.255 mV/V/kPa and a sensing resolution of less than 100 Pa at room temperature. The sensor has a temperature coefficient of sensitivity (TCS) of -0.221 %FS/°C and a temperature coefficient of offset (TCO) of -0.209 %FS/°C at operating temperatures ranging from 20 °C to 160 °C. The reported piezoresistive microelectromechanical systems (MEMS) pressure sensors are fabricated on 8-inch wafers using standard CMOS-compatible processes, which provides a volume solution for embedded integrated precision detection applications of air pressure, offering better insights for high-temperature and miniaturized low-pressure sensor research.

18.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293113

RESUMO

It has been established that kallikrein12 (KLK12) expression is closely related to bovine tuberculosis (bTB) development. Herein, we sought to clarify the regulatory mechanism of KLK12 and its application in tuberculosis diagnosis. KLK12 knockdown macrophages were produced by siRNA transfection. Bradykinin receptors (BR, including B1R and B2R) were blocked with specific inhibitors. Mannose-capped lipoarabinomannan (ManLAM) was extracted from Mycobacterium bovis (M. bovis) and used to study the mechanism of KLK12 activation. In addition, we constructed different mouse models representing the latent and active stages of M. bovis infection. Mouse models and clinical serum samples were used to assess the diagnostic value of biomarkers. Through the above methods, we confirmed that KLK12 regulates MMP-1 and MMP-9 via BR. KLK12 upregulation is mediated by the M. bovis-specific antigen ManLAM. KLK12, MMP-1, and MMP-9 harbor significant value as serological markers for differentiating between latent and active bTB, especially KLK12. In conclusion, we identified a novel signaling pathway, KLK12/BR/ERK/MMPs, in M. bovis-infected macrophages, which is activated by ManLAM. From this signaling pathway, KLK12 can be used as a serological marker to differentiate between latent and active bTB. Importantly, KLK12 also has enormous potential for the clinical diagnosis of human tuberculosis (TB).


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose Bovina , Tuberculose , Camundongos , Animais , Bovinos , Humanos , Tuberculose Bovina/diagnóstico , Tuberculose Bovina/metabolismo , Mycobacterium tuberculosis/metabolismo , Manose/metabolismo , Metaloproteinase 1 da Matriz , Receptores da Bradicinina , Metaloproteinase 9 da Matriz , RNA Interferente Pequeno , Antígenos de Bactérias , Biomarcadores , Calicreínas
19.
Artigo em Inglês | MEDLINE | ID: mdl-36054383

RESUMO

Recently, facial priors (e.g., facial parsing maps and facial landmarks) have been widely employed in prior-guided face super-resolution (FSR) because it provides the location of facial components and facial structure information, and helps predict the missing high-frequency (HF) information. However, most existing approaches suffer from two shortcomings: 1) the extracted facial priors are inaccurate since they are extracted from low-resolution (LR) or low-quality super-resolved (SR) face images and 2) they only consider embedding facial priors into the reconstruction process from LR to SR face images, thus failing to explore facial priors to generate LR face image. In this article, we propose a novel pre-prior guided approach that extracts facial prior information from original high-resolution (HR) face images and embeds them into LR ones to obtain HF information-rich LR face images, thereby improving the performance of face reconstruction. Specifically, a novel component hybrid method is proposed, which fuses HR facial components and LR facial background to generate new LR face images (namely, LRmix) via facial parsing maps extracted from HR face images. Furthermore, we design a component hybrid network (CHNet) that learns the LR to LRmix mapping function to ensure that the LRmix can be obtained from LR face images in testing and real-world datasets. Experimental results show that our proposed scheme significantly improves the reconstruction performance for FSR.

20.
Comput Intell Neurosci ; 2022: 1610658, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093492

RESUMO

White blood cell (WBC) morphology examination plays a crucial role in diagnosing many diseases. One of the most important steps in WBC morphology analysis is WBC image segmentation, which remains a challenging task. To address the problems of low segmentation accuracy caused by color similarity, uneven brightness, and irregular boundary between WBC regions and the background, a WBC image segmentation network based on U-Net combining residual networks and attention mechanism was proposed. Firstly, the ResNet50 residual block is used to form the main unit of the encoder structure, which helps to overcome the overfitting problem caused by a small number of training samples by improving the network's feature extraction capacity and loading the pretraining weight. Secondly, the SE module is added to the decoder structure to make the model pay more attention to useful features while suppressing useless ones. In addition, atrous convolution is utilized to recover full-resolution feature maps in the decoder structure to increase the receptive field of the convolution layer. Finally, network parameters are optimized using the Adam optimization technique in conjunction with the binary cross-entropy loss function. Experimental results on BCISC and LISC datasets show that the proposed approach has higher segmentation accuracy and robustness.


Assuntos
Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos
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