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1.
Sensors (Basel) ; 22(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35746186

RESUMO

The extremely low power transmission levels of ultra-wideband (UWB) technology, alongside its advantageously large bandwidth, make it a prime candidate for being used in numerous healthcare scenarios, which require short-range high-data-rate communications and safe radar-based applications [...].


Assuntos
Radar
2.
Malar J ; 19(1): 29, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952536

RESUMO

BACKGROUND: Anopheles maculipennis complex, the historic vector of malaria, causes serious medical problems worldwide and exhibits different behaviours. Studying the odorant-binding proteins (OBPs), which influence the chemosensory system and behavioural responses, is essential to understanding the population structure and developing effective control measures against this vector. The present study was designed to identify and analyse the obp1 gene in An. maculipennis. METHODS: Adults of An. maculipennis sensu stricto were collected in Zanjan Province, northwest of Iran, and gDNAs of female mosquitoes were extracted. Fragments of An. maculipennis obp1 (Amacobp1) gene were amplified using degenerate and specific primers, and some of amplicons were selected for sequencing. RESULTS: Analysis of amplified products identified that the sequence of Amacobp1 gene was 1341 bp long. This gene contains three exons (5', internal, and 3'of 160, 256, and 18 bp, respectively) and encodes 144 amino acids. The sizes of introns I and II in deduced gene are 268 and 358 nucleotides, respectively. The amino acid sequence in the C-terminal of AmacOBP1 is similar to that of major malaria vector Anopheles species. However, its N-terminal has a specific signal peptide with 19 amino acids. This peptide is conserved in different studied populations, and its sequence of amino acids shows the most variation among anopheline species. CONCLUSIONS: Degenerate primers in this study are suggested for studying obp1 gene in Anopheles species. Amacobp1 gene is proposed as a molecular marker for the detection of intraspecific ecotypes and diagnosis of different species within Maculipennis Group. Moreover, the N-terminal of AmacOBP1 peptide is recommended as a molecular marker to identify the Amacobp1 expression patterns in different chemosensory organs for assessing the molecular mechanisms and developing novel behavioural disturbance agents to control An. maculipennis.


Assuntos
Anopheles/química , Mosquitos Vetores/química , Receptores Odorantes/genética , Sequência de Aminoácidos , Animais , Anopheles/classificação , Anopheles/genética , Sequência de Bases , DNA/química , DNA/genética , DNA/isolamento & purificação , Éxons , Feminino , Íntrons , Irã (Geográfico) , Masculino , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Filogenia , Sinais Direcionadores de Proteínas/genética , Sinais Direcionadores de Proteínas/fisiologia , Receptores Odorantes/química , Alinhamento de Sequência
3.
Sensors (Basel) ; 20(19)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998256

RESUMO

In this paper, we present an investigation of different artefact removal methods for ultra-wideband Microwave Imaging (MWI) to evaluate and quantify current methods in a real environment through measurements using an MWI device. The MWI device measures the scattered signals in a multi-bistatic fashion and employs an imaging procedure based on Huygens principle. A simple two-layered phantom mimicking human head tissue is realised, applying a cylindrically shaped inclusion to emulate brain haemorrhage. Detection has been successfully achieved using the superimposition of five transmitter triplet positions, after applying different artefact removal methods, with the inclusion positioned at 0°, 90°, 180°, and 270°. The different artifact removal methods have been proposed for comparison to improve the stroke detection process. To provide a valid comparison between these methods, image quantification metrics are presented. An "ideal/reference" image is used to compare the artefact removal methods. Moreover, the quantification of artefact removal procedures through measurements using MWI device is performed.


Assuntos
Artefatos , Acidente Vascular Cerebral Hemorrágico , Imageamento de Micro-Ondas , Algoritmos , Acidente Vascular Cerebral Hemorrágico/diagnóstico por imagem , Humanos , Imagens de Fantasmas
4.
Sensors (Basel) ; 19(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669319

RESUMO

Home monitoring and remote care systems aim to ultimately provide independent living care scenarios through non-intrusive, privacy-protecting means. Their main aim is to provide care through appreciating normal habits, remotely recognizing changes and acting upon those changes either through informing the person themselves, care providers, family members, medical practitioners, or emergency services, depending on need. Care giving can be required at any age, encompassing young to the globally growing aging population. A non-wearable and unobtrusive architecture has been developed and tested here to provide a fruitful health and wellbeing-monitoring framework without interfering in a user's regular daily habits and maintaining privacy. This work focuses on tracking locations in an unobtrusive way, recognizing daily activities, which are part of maintaining a healthy/regular lifestyle. This study shows an intelligent and locally based edge care system (ECS) solution to identify the location of an occupant's movement from daily activities using impulse radio-ultra wide band (IR-UWB) radar. A new method is proposed calculating the azimuth angle of a movement from the received pulse and employing radar principles to determine the range of that movement. Moreover, short-term fourier transform (STFT) has been performed to determine the frequency distribution of the occupant's action. Therefore, STFT, azimuth angle, and range calculation together provide the information to understand how occupants engage with their environment. An experiment has been carried out for an occupant at different times of the day during daily household activities and recorded with time and room position. Subsequently, these time-frequency outcomes, along with the range and azimuth information, have been employed to train a support vector machine (SVM) learning algorithm for recognizing indoor locations when the person is moving around the house, where little or no movement indicates the occurrence of abnormalities. The implemented framework is connected with a cloud server architecture, which enables to act against any abnormality remotely. The proposed methodology shows very promising results through statistical validation and achieved over 90% testing accuracy in a real-time scenario.

5.
Parasitol Res ; 117(5): 1433-1442, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29541856

RESUMO

The human flea is an important ectoparasite causing serious public health problems worldwide. Planning and monitoring the control programs against this vector require the knowledge of population structure and vector competence. This study was carried out to identify molecular structure of internal transcribed spacer 1 (ITS1) of ribosomal gene and its capability in the survey of Pulex irritans populations as well as to investigate Rickettsia infection in these populations. Flea samples were collected via human baits from animal farms in two districts of Zanjan Province, northwest of Iran. The ITS1 region and the partial Rickettsia gltA gene were amplified from the samples of human flea, and 30 amplicons were sequenced. The 1136 collected fleas consisted of 1079 (94.98%) P. irritans, 36 (3.17%) Ctenocephalides canis, and 21 (1.85%) Ctenocephalides felis. Molecular investigation of 182 human fleas detected the infection of Rickettsia sp. in 4.9%. The ITS1 region covered 957 bp and contained three tandem units of 98-99 bp, starting at positions 145, 245, and 331. Multiple alignments of ITS1 sequences showed single-nucleotide polymorphism at position 798, which caused the substitution of cytosine for adenine in the novel haplotype. High frequency of P. irritans and its Rickettsia infection requires the application of vector control measures, and full characterization of Rickettsia sp. and its potential to cause disease in humans. Regarding the consistency of ITS1 region and its ability to differentiate insect communities, further investigations are recommended to identify the role of selective factors in maintenance of this spacer.


Assuntos
Ctenocephalides/microbiologia , DNA Intergênico/genética , Infecções por Rickettsia/microbiologia , Rickettsia/genética , Sifonápteros/microbiologia , Animais , Proteínas de Bactérias/genética , Sequência de Bases , Gatos , Vetores de Doenças , Infestações por Pulgas/veterinária , Haplótipos , Humanos , Irã (Geográfico) , Polimorfismo de Nucleotídeo Único/genética , Rickettsia/isolamento & purificação , Inquéritos e Questionários
6.
Pestic Biochem Physiol ; 146: 97-105, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29626998

RESUMO

The human flea, Pulex irritans, is the most important ectoparasite of humans. Intensive use of pyrethroids for its control has led to insecticide resistance. Monitoring pyrethroid resistance and its underlying mechanisms is essential for flea control. The aims of this study were to identify the susceptibility status of human flea to permethrin and to detect the presence of knockdown resistance (kdr) mutation and its frequency in populations of P. irritans. Adults of P. irritans were collected from Zanjan Province, northwest of Iran, during 2013-2017. Different populations of this flea were exposed to permethrin 0.75% for one and 8 h and then the mortality rate, as well as KD50 and KD95 times were calculated. Total RNA and gDNA of samples were extracted, and the fragments of cDNA encoding the partial voltage-gated sodium channel (VGSC) peptides were amplified using degenerated primers. Specific PCR and TaqMan real-time assays were conducted to characterize the vgsc gene and to detect the presence of mutation and genotyping of the populations. Mortality rates were in the range from 32% to 67% for one-hour and 73% to 90% for eight-hour exposure to permethrin 0.75%. KD50 and KD95 times varied in a range from 46 to 241 and 177 to 899 min, respectively. Sequencing of 70 amplified fragments of gDNA resulted in a 578-bp product. These fragments contained two introns (92 and 63 bp) and three exons (141, 189, and 92 bp) encoding 138 amino acids that encompassed IIS4-IIS6 and the partial linker between domains II and III of VGSC. All the studied populations showed L1014F mutation, substitution of CTT for TTT at the 1014 allele. The result of TaqMan assay for 624 samples showed 96.6% homogenous and 3.36% heterozygous mutant. The development of permethrin resistance and the presence of the L1014F mutation at high frequency in flea populations indicate that pyrethroids are likely ineffective in controlling human flea. Therefore, novel alternative control methods are needed to combat this human ectoparasite.


Assuntos
Piretrinas/farmacologia , Sifonápteros/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Sequência de Bases , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência
7.
East Mediterr Health J ; 30(2): 145-155, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38491900

RESUMO

Background: Tick-borne rickettsioses have become a health concern worldwide following the increasing incidence in recent decades. However, there is limited information about these diseases in Islamic Republic of Iran. Aim: This cross-sectional study was conducted to estimate the Rickettsia infection among ixodid ticks collected from cattle, sheep and goats in Islamic Republic of Iran. Methods: The DNA of ixodid ticks collected from cattle, sheep and goats in 54 villages of Zanjan Province, Islamic Republic of Iran, were collected and analysed using a spectrophotometer. Rickettsial-positive samples were screened by targeting the htrA gene and fragments of gltA gene were analysed. The variables were analysed using descriptive statistics and the χ2 test was used to compare the variables. Results: A total of 528 ticks were tested. Overall, Rickettsia infection rate was 6.44%. Nine of the 12 tick species were infected. Rickettsial positive rates in Hyalomma marginatum and Dermacentor marginatus were 21.33% and 12.77%, respectively. R. aeschlimannii, the predominant rickettsia, was detected only in Hy. marginatum. R. raoultii, R. sibirica and R. slovaca comprised about half of the positive ticks and were recovered from more than one tick species. Conclusion: Considering the discovery of infected ticks in the Islamic Republic of Iran, there is a need to establish a tick control programme in the country, paying attention to populations at high-risk.


Assuntos
Ixodidae , Infecções por Rickettsia , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Animais , Humanos , Bovinos , Ovinos , Irã (Geográfico)/epidemiologia , Estudos Transversais , DNA Bacteriano/genética , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Rickettsia/genética , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/veterinária , Infecções por Rickettsia/microbiologia , Carrapatos/genética , Carrapatos/microbiologia , Cabras
8.
Parasit Vectors ; 16(1): 57, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747269

RESUMO

BACKGROUND: Head louse infestation is an important public health problem, and expanding resistance to permethrin is a major challenge to its control. The mapping and detection of pyrethroid resistance are essential to the development of appropriate treatments and ensure the effectiveness of current measures. The aim of this study was to present the phenotypic and genotypic basis of permethrin resistance and identify knockdown resistance (kdr) mutations in head louse populations in northwestern Iran. METHODS: Adult head lice were collected from 1059 infested girls in Ardebil, East Azerbaijan, West Azerbaijan and Zanjan Provinces, northwestern Iran. The toxicity of permethrin and the possible synergistic effect of piperonyl butoxide (PBO) on this toxicity were assessed using bioassays. Fragments of voltage-sensitive sodium channels (vssc) and cytochrome b (cytb) genes were amplified and analyzed for the detection of knockdown resistance (kdr) mutations and mitochondrial groups. Moreover, genotypes of the two hot spot regions of the vssc gene were determined by melting curve analysis of amplicons. RESULTS: A total of 1450 adult head lice were collected during 2016-2021. Live lice were exposed to a dose of 1% permethrin for 12 h, and the median lethal time (LT50) and time to achieve 90% mortality (LT90) were determined to be 6 and 14.8 h, respectively. Topical application of 2 and 16 ng permethrin per louse resulted in 25% and 42.11% mortality, respectively. Pre-exposure of samples to 3% piperonyl butoxide had no synergistic effect on the effects of permethrin. Analysis of the 774-bp vssc gene fragment showed the presence of the M815I, T917I and L920F mutations, wild-type and T917I mutation, in 91.6%, 4.2% and 4.2% of samples, respectively. Investigation of the mitochondrial cytb gene demonstrated the predominance of clade B. The frequency of domain II segment 4 (S4)-S5 kdr genotypes in mitochondrial groups was identical, and heterozygotes were present in 93.5% of samples. A significant difference was detected in the frequency of domain IIS1-S3 kdr genotypes, and the frequency of resistant alleles and heterozygotes was higher in clade B than in clade A. CONCLUSIONS: The presence of kdr mutations in the vssc gene and the non-synergist effect of PBO indicate that pyrethroid target site insensitivity is the main resistance mechanism. This phenomenon and the high frequency of resistant alleles necessitate that new pediculosis management programs be developed. Further studies need to be conducted to identify all factors contributing this resistance and to develop alternative pediculicides.


Assuntos
Inseticidas , Infestações por Piolhos , Pediculus , Piretrinas , Animais , Adulto , Feminino , Humanos , Permetrina/farmacologia , Pediculus/genética , Alelos , Butóxido de Piperonila/farmacologia , Irã (Geográfico) , Resistência a Inseticidas/genética , Piretrinas/farmacologia , Inseticidas/farmacologia
9.
Tomography ; 9(1): 105-129, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36648997

RESUMO

Mammography is the gold standard technology for breast screening, which has been demonstrated through different randomized controlled trials to reduce breast cancer mortality. However, mammography has limitations and potential harms, such as the use of ionizing radiation. To overcome the ionizing radiation exposure issues, a novel device (i.e. MammoWave) based on low-power radio-frequency signals has been developed for breast lesion detection. The MammoWave is a microwave device and is under clinical validation phase in several hospitals across Europe. The device transmits non-invasive microwave signals through the breast and accumulates the backscattered (returned) signatures, commonly denoted as the S21 signals in engineering terminology. Backscattered (complex) S21 signals exploit the contrast in dielectric properties of breasts with and without lesions. The proposed research is aimed to automatically segregate these two types of signal responses by applying appropriate supervised machine learning (ML) algorithm for the data emerging from this research. The support vector machine with radial basis function has been employed here. The proposed algorithm has been trained and tested using microwave breast response data collected at one of the clinical validation centres. Statistical evaluation indicates that the proposed ML model can recognise the MammoWave breasts signal with no radiological finding (NF) and with radiological findings (WF), i.e., may be the presence of benign or malignant lesions. A sensitivity of 84.40% and a specificity of 95.50% have been achieved in NF/WF recognition using the proposed ML model.


Assuntos
Neoplasias da Mama , Micro-Ondas , Humanos , Feminino , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Aprendizado de Máquina Supervisionado , Tecnologia
10.
PLoS One ; 18(7): e0288312, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37450545

RESUMO

Microwave imaging is a safe and promising new technology in breast radiology, avoiding discomfort of breast compression and usage of ionizing radiation. This paper presents the first prospective microwave breast imaging study during which both symptomatic and asymptomatic subjects were recruited. Specifically, a prospective multicentre international clinical trial was performed in 2020-2021, to investigate the capability of a microwave imaging device (MammoWave) in allowing distinction between breasts with no radiological finding (NF) and breasts with radiological findings (WF), i.e., with benign or malignant lesions. Each breast scan was performed with the volunteers lying on a dedicated examination table in a comfortable prone position. MammoWave output was compared to reference standard (i.e., radiologic study obtained within the last month and integrated with histological one if available and deemed necessary by responsible investigator) to classify breasts into NF/WF categories. MammoWave output consists of a selection of microwave images' features (determined prior to trials' start), which allow distinction between NF and WF breasts (using statistical significance p<0.05). 353 women were enrolled in the study (mean age 51 years ± 12 [SD], minimum age 19, maximum age 78); MammoWave data from the first 15 women of each site, all with NF breasts, were used for calibration. Following central assessor evaluation, 111 NF (48 dense) and 272 WF (136 dense) breasts were used for comparison with MammoWave output. 272 WF comprised 182 benign findings and 90 malignant histology-confirmed cancer. A sensitivity of 82.3% was achieved (95%CI: 0.78-0.87); sensitivity is maintained when limiting the investigation to histology-confirmed breasts cancer only (90 histology-confirmed breasts cancer have been included in this analysis, having sizes ranging from 3 mm to 60 mm). Specificity value of approximately 50% was achieved as expected, since thresholds were calculated (for each feature) using median value obtained after recruiting the first 15 women (of each site), all NF. This prospective trial may represent another step for introducing microwave imaging into clinical practice, for helping in breast lesion identification in asymptomatic women.


Assuntos
Neoplasias da Mama , Neoplasias , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Adulto , Idoso , Mamografia/métodos , Estudos Prospectivos , Sensibilidade e Especificidade , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem
11.
Diagnostics (Basel) ; 13(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37370995

RESUMO

Novel techniques, such as microwave imaging, have been implemented in different prototypes and are under clinical validation, especially for breast cancer detection, due to their harmless technology and possible clinical advantages over conventional imaging techniques. In the prospective study presented in this work, we aim to investigate through a multicentric European clinical trial (ClinicalTrials.gov Identifier NCT05300464) the effectiveness of the MammoWave microwave imaging device, which uses a Huygens-principle-based radar algorithm for image reconstruction and comprises dedicated image analysis software. A detailed clinical protocol has been prepared outlining all aspects of this study, which will involve adult females having a radiologist study output obtained using conventional exams (mammography and/or ultrasound and/or magnetic resonance imaging) within the previous month. A maximum number of 600 volunteers will be recruited at three centres in Italy and Spain, where they will be asked to sign an informed consent form prior to the MammoWave scan. Conductivity weighted microwave images, representing the homogeneity of the tissues' dielectric properties, will be created for each breast, using a conductivity = 0.3 S/m. Subsequently, several microwave image parameters (features) will be used to quantify the images' non-homogenous behaviour. A selection of these features is expected to allow for distinction between breasts with lesions (either benign or malignant) and those without radiological findings. For all the selected features, we will use Welch's t-test to verify the statistical significance, using the gold standard output of the radiological study review.

12.
J Arthropod Borne Dis ; 16(2): 84-96, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37038503

RESUMO

Background: Androctonus crassicauda is the most medically relevant scorpion and understanding its genetic forms is essential for improvement of anti-venom sera, and risk management of scorpionism. Present study was designed to identify the variations of mitochondrial genes in different populations of A. crassicauda. Methods: Adults of A. crassicauda were collected from Zanjan Province during 2016-2017. Genomic DNA of samples was extracted and fragments of mitochondrial 16S, COI and ND1 genes were amplified and some of the amplicons were sequenced. Haplotype of samples were identified by multiple alignment of sequences, then phylogenetic trees of haplotypes were constructed. Results: Fragments of 352bp, 618bp and 680bp were amplified from 16S, COI and ND1 genes respectively. Nucleotide sequence in COI fragments was conserved, however, five haplotypes with some specific polymorphic sites were detected in 16S and ND1 fragments. Haplotype I was dominant and found in all areas. Other haplotypes were rare and limited to specific regions. Analysis of the phylogenetic trees inferred from 16S and COI genes, confirmed a strong positive correlation between geographic and genetic distance. Conclusion: Mitochondrial COI, 16S and ND1 genes were detected suitable for identifying the population structure. Five genotypes were found using 16S and ND1 genes. To prepare and improve the anti-venoms quality, additional studies are necessary to identify the toxin electrophoretic profile and geographical/ecological niche models of these genotypes in future.

13.
J Arthropod Borne Dis ; 16(1): 13-25, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36636242

RESUMO

Background: Androctonus crassicauda is the most medically relevant animal and understanding its morphological characteristics is essential in the production of antiscorpion sera. Methods: Adults of A. crassicauda were collected from different areas of Zanjan Province and the morphometric parameters and the cuticular fluorescence patterns of samples were studied. The crude venom of samples was extracted by electric stimulation, and their biochemical properties were analyzed by the SDS-PAGE method. Results: Values of the morphometric parameters depended on sex and altitude of the area. Except for values of the pectinal organ, these parameters in females were higher than in males. No significant difference was in the number, shape, and intensity of cuticular fluorescence patterns. The body length of males in high and lowlands was 72.53±1.53 and 77.33±2.70mm, respectively. Females' body lengths in that area were 81.66±2.19 and 86.55±2.33mm, respectively. Analysis of toxin proteins showed two isotypes that the 12, 13, 15, 16, 18, and 19kDa proteins were in all areas. However, the 41 and 74kDa proteins, and 46 and 63kDa proteins were detected in low and highlands, respectively. Conclusion: Black fat-tailed scorpion has a considerable dominancy and developing preventive programs and providing treatment facilities in studied areas are necessary. Values of the morphological parameters and venom electrophoresis patterns depended on the geographical location. Therefore, pool crude toxin is suggested for the production of effective antivenoms. Moreover, additional field complementary works in the geographic information system based niche modeling and mass fingerprinting of scorpion venoms are suggested for screening effective isotypes.

14.
PLoS One ; 17(7): e0271377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862368

RESUMO

MammoWave is a microwave imaging device for breast lesion detection, employing two antennas which rotate azimuthally (horizontally) around the breast. The antennas operate in the 1-9 GHz band and are set in free space, i.e., pivotally, no matching liquid is required. Microwave images, subsequently obtained through the application of Huygens Principle, are intensity maps, representing the homogeneity of the dielectric properties of the breast tissues under test. In this paper, MammoWave is used to realise tissues dielectric differences and localise lesions by segmenting microwave images adaptively employing pulse coupled neural network (PCNN). Subsequently, a non-parametric thresholding technique is modelled to differentiate between breasts having no radiological finding (NF) or benign (BF) and breasts with malignant finding (MF). Resultant findings verify that automated breast lesion localization with microwave imaging matches the gold standard achieving 81.82% sensitivity in MF detection. The proposed method is tested on microwave images acquired from a feasibility study performed in Foligno Hospital, Italy. This study is based on 61 breasts from 35 patients; performance may vary with larger number of datasets and will be subsequently investigated.


Assuntos
Neoplasias da Mama , Imageamento de Micro-Ondas , Algoritmos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Diagnóstico por Imagem , Feminino , Humanos , Micro-Ondas , Redes Neurais de Computação
15.
Parasit Vectors ; 14(1): 470, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521460

RESUMO

BACKGROUND: The tropical bed bug, Cimex hemipterus, is an important ectoparasite causing various health problems. This species is mainly confined to tropical regions; however, insecticide resistance, global warming, and globalization have changed its distribution map. Molecular information on pyrethroid resistance, which is essential for the development of control programs, is unknown for C. hemipterus in expanded areas. The present study was designed to determine the permethrin resistance status, characterize the pyrethroid receptor sites in voltage-gated sodium channel (vgsc) gene, and identify the resistance-related mutations in the populations of tropical bed bug in Iran. METHODS: Live bed bugs were collected, and adults of C. hemipterus were selected for bioassay and molecular surveys. Bioassay was performed by tarsal contact with permethrin 0.75% in mixed-sex of samples. Conventional and quantitative TaqMan and SYBR Green real-time PCR assays were conducted to characterize the vgsc gene and genotypes of studied populations. RESULTS: In the bioassay tests, the mortality rates were in the range of 30.7-38.7% and 56.2-77.4% in 24 and 48 h, respectively. The knockdown rates of studied populations were in the range of 32.2-46.6% and 61.5-83.8% in the first and second days, respectively. The KT50 and KT90 values in the Cimex lectularius Kh1 strain were presented as 5.39 and 15.55 h, respectively. These values in the selected populations of C. hemipterus varied from 27.9 to 29.5 and from 82.8 to 104.4 h, respectively. Knockdown time ratios (KR50 and KR90) in these populations varied from 5.17 to 6.17-fold compared with those of the C. lectularius Kh1 strain. Fragments of vgsc gene with 355 bp and 812 bp were amplified. Analysis of sequences revealed the A468T substitution, kdr-associated D953G, and super-kdr M918I and L1014F mutations in all populations. CONCLUSIONS: The specific/sensitive, safe, and rapid diagnostic assays developed in this study are recommended for detection of kdr/super-kdr mutations and frequency of mutant alleles. The presence of super-kdr mutations and high resistance to permethrin in all the populations necessitate the reconsideration of control approaches against C. hemipterus.


Assuntos
Percevejos-de-Cama/genética , Resistência a Inseticidas/genética , Permetrina/farmacologia , Piretrinas/farmacologia , Canais de Sódio Disparados por Voltagem/genética , Animais , Percevejos-de-Cama/efeitos dos fármacos , Feminino , Inseticidas/farmacologia , Irã (Geográfico) , Masculino , Mutação , Reação em Cadeia da Polimerase em Tempo Real
16.
Diagnostics (Basel) ; 11(10)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34679628

RESUMO

Recently, a novel microwave apparatus for breast lesion detection (MammoWave), uniquely able to function in air with 2 antennas rotating in the azimuth plane and operating within the band 1-9 GHz has been developed. Machine learning (ML) has been implemented to understand information from the frequency spectrum collected through MammoWave in response to the stimulus, segregating breasts with and without lesions. The study comprises 61 breasts (from 35 patients), each one with the correspondent output of the radiologist's conclusion (i.e., gold standard) obtained from echography and/or mammography and/or MRI, plus pathology or 1-year clinical follow-up when required. The MammoWave examinations are performed, recording the frequency spectrum, where the magnitudes show substantial discrepancy and reveals dissimilar behaviours when reflected from tissues with/without lesions. Principal component analysis is implemented to extract the unique quantitative response from the frequency response for automated breast lesion identification, engaging the support vector machine (SVM) with a radial basis function kernel. In-vivo feasibility validation (now ended) of MammoWave was approved in 2015 by the Ethical Committee of Umbria, Italy (N. 6845/15/AV/DM of 14 October 2015, N. 10352/17/NCAV of 16 March 2017, N 13203/18/NCAV of 17 April 2018). Here, we used a set of 35 patients. According to the radiologists conclusions, 25 breasts without lesions and 36 breasts with lesions underwent a MammoWave examination. The proposed SVM model achieved the accuracy, sensitivity, and specificity of 91%, 84.40%, and 97.20%. The proposed ML augmented MammoWave can identify breast lesions with high accuracy.

17.
PLoS One ; 16(4): e0250005, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33848318

RESUMO

MammoWave is a microwave imaging device for breast lesions detection, which operates using two (azimuthally rotating) antennas without any matching liquid. Images, subsequently obtained by resorting to Huygens Principle, are intensity maps, representing the homogeneity of tissues' dielectric properties. In this paper, we propose to generate, for each breast, a set of conductivity weighted microwave images by using different values of conductivity in the Huygens Principle imaging algorithm. Next, microwave images' parameters, i.e. features, are introduced to quantify the non-homogenous behaviour of the image. We empirically verify on 103 breasts that a selection of these features may allow distinction between breasts with no radiological finding (NF) and breasts with radiological findings (WF), i.e. with lesions which may be benign or malignant. Statistical significance was set at p<0.05. We obtained single features Area Under the receiver operating characteristic Curves (AUCs) spanning from 0.65 to 0.69. In addition, an empirical rule-of-thumb allowing breast assessment is introduced using a binary score S operating on an appropriate combination of features. Performances of such rule-of-thumb are evaluated empirically, obtaining a sensitivity of 74%, which increases to 82% when considering dense breasts only.


Assuntos
Mama/diagnóstico por imagem , Mamografia/métodos , Adulto , Idoso , Algoritmos , Área Sob a Curva , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Mamografia/instrumentação , Imageamento de Micro-Ondas , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Adulto Jovem
18.
Parasit Vectors ; 13(1): 485, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32967705

RESUMO

BACKGROUND: The head louse, Pediculus humanus capitis, is the most important ectoparasite causing many health problems. Several linkages are presented for this parasite, each representing a particular geographical distribution, prevalence rate, vector competence, susceptibility to pediculicides, and infestation rate. Determining the genetic nature of these linkages is necessary to identify the population structure and also to develop and monitor control programmes against head lice. This study was designed to analyse cox1 and cytb genes and determine the mitochondrial clades in head lice populations in the northwest of Iran. METHODS: Adult head lice were collected from infested females of Ardabil, East and West Azerbaijan, and Zanjan Provinces from 2016 to 2018. Partial fragments of the mitochondrial genes cox1 and cytb were amplified by PCR and some of the amplicons were sequenced. All confirmed sequences were analysed, and the frequency of each mitochondrial clade was determined in the studied areas. RESULTS: A total of 6410 females were clinically examined, and 897 adult head lice were collected from 562 infested cases. Genomic DNA was extracted from 417 samples, and fragments of cox1 and cytb genes were amplified in 348 individuals. Analysis of the 116 sequences showed the 632-bp and 495-bp fragments for cox1 and cytb genes, respectively. The nucleotide and haplotype diversities of cytb and cox1 genes were 0.02261 and 0.589 and 0.01443 and 0.424, respectively. Sequence analysis indicated 6 haplotypes clustered in two clades, A and B. The relative prevalence of clade B was 73% for cytb and 82% for cox1 gene. Haplotypes of clade B were found in all the studied areas, while those of clade A were observed only in rural and suburban areas. CONCLUSIONS: To our knowledge, this is the first study investigated deeply the field populations of Pediculus and documented two clades in the Middle East. The considerable prevalence of pediculosis in the studied areas requires authorities' attention to establish effective control and preventive measures. Given the role of cytb in monitoring population groups, application of this marker is suggested for future epigenetic studies to evaluate the factors affecting the abundance of these clades.


Assuntos
Biodiversidade , Genes Mitocondriais , Infestações por Piolhos/parasitologia , Pediculus/classificação , Pediculus/genética , Adolescente , Animais , Criança , Citocromos b/genética , Feminino , Variação Genética , Humanos , Irã (Geográfico) , Masculino , Proteínas Mitocondriais/genética , Pediculus/anatomia & histologia , Filogenia
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 782-787, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946012

RESUMO

A more locally cared for and self-managing aging population along with better attention to self health-care, has resulted in increasing need for non-intrusive monitoring. Wearable, wireless physiological sensors, and cameras can pose user privacy, security and discomfort issues which may have a negative impact on consumer confidence and uptake. Thus, for the first time a non-contact, non-intrusive 3D human motion model is proposed for gait disorder identification from impulse radio ultra-wide band (ITERATOR) with the understanding of spherical trigonometry and vector field. Simultaneously, the Kinect Xbox One is used to compare the outcomes of the proposed IR-UWB model. The experiment comprises twenty-four human participants, where twenty people have normal walking pattern and four persons have spasticity. The height of different body sections from the ground have been recorded for each individual and employed later to distinguish lower and upper human body from the outcomes. The proposed work has transformed the radars backscattered responses through trigonometry and vector algebra where, only vector algebra has been implemented to transform the skeletal data obtained from Kinect. Angles between two thighs have been determined from the proposed UWB algorithm and validated against angles obtained from the Kinect skeletal data using root mean square error (RMSE), where less than 0.5 RMSE has been found.


Assuntos
Marcha , Algoritmos , Humanos , Tecnologia sem Fio
20.
Sci Rep ; 9(1): 10510, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324863

RESUMO

Breast lesion detection employing state of the art microwave systems provide a safe, non-ionizing technique that can differentiate healthy and non-healthy tissues by exploiting their dielectric properties. In this paper, a microwave apparatus for breast lesion detection is used to accumulate clinical data from subjects undergoing breast examinations at the Department of Diagnostic Imaging, Perugia Hospital, Perugia, Italy. This paper presents the first ever clinical demonstration and comparison of a microwave ultra-wideband (UWB) device augmented by machine learning with subjects who are simultaneously undergoing conventional breast examinations. Non-ionizing microwave signals are transmitted through the breast tissue and the scattering parameters (S-parameter) are received via a dedicated moving transmitting and receiving antenna set-up. The output of a parallel radiologist study for the same subjects, performed using conventional techniques, is taken to pre-process microwave data and create suitable data for the machine intelligence system. These data are used to train and investigate several suitable supervised machine learning algorithms nearest neighbour (NN), multi-layer perceptron (MLP) neural network, and support vector machine (SVM) to create an intelligent classification system towards supporting clinicians to recognise breasts with lesions. The results are rigorously analysed, validated through statistical measurements, and found the quadratic kernel of SVM can classify the breast data with 98% accuracy.


Assuntos
Mama/diagnóstico por imagem , Imageamento de Micro-Ondas , Redes Neurais de Computação , Máquina de Vetores de Suporte , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Ensaios Clínicos como Assunto , Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Desenho de Equipamento , Feminino , Humanos , Imageamento por Ressonância Magnética , Mamografia , Curva ROC , Espalhamento de Radiação , Estatísticas não Paramétricas , Ultrassonografia Mamária
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