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1.
Biosensors (Basel) ; 14(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38534256

RESUMO

A proof-of-concept of a microwave imaging system for the fast detection of abdominal aortic aneurysms is shown. This experimental technology seeks to overcome the factors hampering the fast screening for these aneurysms with the usual equipment, such as high cost, long-time operation or hazardous exposure to chemical substances. The hardware system is composed of 16 twin antennas mastered by a microcontroller through a switching network, which connects the antennas to the measurement instrument for sequential measurement. The software system is run by a computer, mastering the whole system, automatizing the measurement process and running the signal processing and medical image generation algorithms. Two image generation algorithms are tested: Delay-and-Sum (DAS) and Improved Delay-and-Sum (IDAS). Own-modified versions of these algorithms adapted to the requirements of our system are proposed. The system is carefully calibrated and fine-tuned with known objects placed at known distances. An experimental proof-of-concept is shown with a human torso phantom, including an aorta phantom and an aneurysm phantom placed in different positions. The results show good imaging capabilities with the potential for detecting and locating possible abdominal aortic aneurysms and reporting acceptable errors.


Assuntos
Aneurisma da Aorta Abdominal , Imageamento de Micro-Ondas , Humanos , Aneurisma da Aorta Abdominal/diagnóstico , Software , Algoritmos , Imagens de Fantasmas
2.
Artigo em Inglês | MEDLINE | ID: mdl-38083476

RESUMO

Deficient visualization in minimally invasive surgery often causes misperceptions, which can lead to an increase of iatrogenic lesions and complications. This is especially critical for novice surgeons, who are prone to adopt inadequate switching gaze strategies, thereby increasing the chance of unforeseen complications. In this paper the use of an additional computer-aided vision system was tested for improvement of the reaction of the surgeons to unforeseen complications. Gaze patterns were analyzed using a gaze tracker, as well as other metrics such as task completion time or reaction time to sudden bleeding. While completion time did not show significant difference between tested modalities (p<0.1), the reaction time showed a downward trend as more auxiliary computer-aided vision systems were added (p<0.005). These results support the benefits of including additional vision systems for minimally invasive surgery processes.Clinical Relevance- This work assesses the advantages of including an additional computer vision system to prevent unforeseen complications during minimally invasive surgeries.


Assuntos
Laparoscopia , Cirurgiões , Humanos , Visão Ocular , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Computadores
3.
Artigo em Inglês | MEDLINE | ID: mdl-38083752

RESUMO

An Augmented Reality (AR) system based on the holographic projection of the relevant anatomic structures is proposed for auxiliary visualization during surgeries. The current two-dimensional visualization systems require the surgeons to mentally extract the associated three-dimensional information during the interventions, which entails risks and complications. This work shows an AR holographic projection system for real-time three-dimensional representation of the relevant surgical information, thus overcoming this problem. As an initial proof of concept, the system is experimentally assessed as potential surgery training tool.Clinical Relevance- This work explores the potential of AR holographic projection systems for intraoperative assistance to the surgical team, starting from its possible use as surgery training and planning tool.


Assuntos
Realidade Aumentada , Holografia , Cirurgia Assistida por Computador
4.
Int J Mol Sci ; 24(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36901728

RESUMO

In recent years, invasive fungal infections have emerged as a common source of infections in immunosuppressed patients. All fungal cells are surrounded by a cell wall that is essential for cell integrity and survival. It prevents cell death and lysis resulting from high internal turgor pressure. Since the cell wall is not present in animal cells, it is an ideal target for selective invasive fungal infection treatments. The antifungal family known as echinocandins, which specifically inhibit the synthesis of the cell wall ß(13)glucan, has been established as an alternative treatment for mycoses. To explore the mechanism of action of these antifungals, we analyzed the cell morphology and glucan synthases localization in Schizosaccharomyces pombe cells during the initial times of growth in the presence of the echinocandin drug caspofungin. S. pombe are rod-shaped cells that grow at the poles and divide by a central division septum. The cell wall and septum are formed by different glucans, which are synthesized by four essential glucan synthases: Bgs1, Bgs3, Bgs4, and Ags1. Thus, S. pombe is not only a perfect model for studying the synthesis of the fungal ß(1-3)glucan, but also it is ideal for examining the mechanisms of action and resistance of cell wall antifungals. Herein, we examined the cells in a drug susceptibility test in the presence of either lethal or sublethal concentrations of caspofungin, finding that exposure to the drug for long periods at high concentrations (>10 µg/mL) induced cell growth arrest and the formation of rounded, swollen, and dead cells, whereas low concentrations (<10 µg/mL) permitted cell growth with a mild effect on cell morphology. Interestingly, short-term treatments with either high or low concentrations of the drug induced effects contrary to those observed in the susceptibility tests. Thus, low drug concentrations induced a cell death phenotype that was not observed at high drug concentrations, which caused transient fungistatic cell growth arrest. After 3 h, high concentrations of the drug caused the following: (i) a decrease in the GFP-Bgs1 fluorescence level; (ii) altered locations of Bgs3, Bgs4, and Ags1; and (iii) a simultaneous accumulation of cells with calcofluor-stained incomplete septa, which at longer times resulted in septation uncoupling from plasma membrane ingression. The incomplete septa revealed with calcofluor were found to be complete when observed via the membrane-associated GFP-Bgs or Ags1-GFP. Finally, we found that the accumulation of incomplete septa depended on Pmk1, the last kinase of the cell wall integrity pathway.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Schizosaccharomyces/genética , Antifúngicos/metabolismo , Caspofungina/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Parede Celular/metabolismo , Glucanos/metabolismo , Glucosiltransferases/metabolismo , Equinocandinas
5.
Biosensors (Basel) ; 12(9)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36140137

RESUMO

This work introduces a microwave-based system able to detect tumours in breast phantoms in a non-invasive way. The data acquisition system is composed of a hardware system which involves high-frequency components (antennas, switches and cables), a microcontroller, a vector network analyser used as measurement instrument and a computer devoted to the control and automation of the operation of the system. Concerning the software system, the computer runs a Python script which is in charge of mastering and automatising all the required stages for the data acquisition, from initialisation of the hardware system to performing and saving the measurements. We also report on the design of the high-performance broadband antenna used to carry out the measurements, as well as on the algorithm employed to build the final medical images, based on an adapted version of the so-called Improved Delay-and-Sum (IDAS) algorithm improved by a Hamming window filter and averaging preprocessing. The calibration and start-up of the system are also described. The experimental validation includes the use of different tumour models with different dielectric properties inside the breast phantom. The results show promising tumour detection capabilities, even when there is low dielectric contrast between the tumoural and healthy tissues, as is the usual case for dense breasts in young women.


Assuntos
Neoplasias da Mama , Micro-Ondas , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Calibragem , Feminino , Humanos , Imagens de Fantasmas
6.
Sensors (Basel) ; 22(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35632255

RESUMO

A radio frequency (RF)-based system for surgical navigation is presented. Surgical navigation technologies are widely used nowadays for aiding the surgical team with many interventions. However, the currently available options still pose considerable limitations, such as line-of-sight occlusion prevention or restricted materials and equipment allowance. In this work, we suggest a different approach based on a microwave broadband antenna system. We combine techniques from microwave medical imaging, which can overcome the current limitations in surgical navigation technologies, and we propose methods to develop RF-based systems for real-time tracking neurosurgical tools. The design of the RF system to perform the measurements is shown and discussed, and two methods (Multiply and Sum and Delay Multiply and Sum) for building the medical images are analyzed. From these measurements, a surgical tool's position tracking system is developed and experimentally assessed in an emulated surgical scenario. The reported results are coherent with other approaches found in the literature, while overcoming their main practical limitations. The discussion of the results discloses some hints on the validity of the system, the optimal configurations depending on the requirements, and the possibilities for future enhancements.


Assuntos
Ondas de Rádio , Cirurgia Assistida por Computador , Cirurgia Assistida por Computador/métodos
7.
Mar Drugs ; 20(2)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35200678

RESUMO

The venom duct transcriptomes and proteomes of the cryptic cone snail species Virroconus ebraeus and Virroconus judaeus were obtained and compared. The most abundant and shared conotoxin precursor superfamilies in both species were M, O1, and O2. Additionally, three new putative conotoxin precursor superfamilies (Virro01-03) with cysteine pattern types VI/VII and XVI were identified. The most expressed conotoxin precursor superfamilies were SF-mi2 and M in V. ebraeus, and Cerm03 and M in V. judaeus. Up to 16 conotoxin precursor superfamilies and hormones were differentially expressed between both species, and clustered into two distinct sets, which could represent adaptations of each species to different diets. Finally, we predicted, with machine learning algorithms, the 3D structure model of selected venom proteins including the differentially expressed Cerm03 and SF-mi2, an insulin type 3, a Gastridium geographus GVIA-like conotoxin, and an ortholog to the Pionoconus magus ω-conotoxin MVIIA (Ziconotide).


Assuntos
Caramujo Conus , Venenos de Moluscos/química , Proteínas/química , Algoritmos , Animais , Aprendizado de Máquina , Proteínas/isolamento & purificação , Proteoma , Especificidade da Espécie , Transcriptoma
8.
Pharmaceuticals (Basel) ; 14(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34959732

RESUMO

Fission yeast contains three essential ß(1,3)-D-glucan synthases (GSs), Bgs1, Bgs3, and Bgs4, with non-overlapping roles in cell integrity and morphogenesis. Only the bgs4+ mutants pbr1-8 and pbr1-6 exhibit resistance to GS inhibitors, even in the presence of the wild-type (WT) sequences of bgs1+ and bgs3+. Thus, Bgs1 and Bgs3 functions seem to be unaffected by those GS inhibitors. To learn more about echinocandins' mechanism of action and resistance, cytokinesis progression and cell death were examined by time-lapse fluorescence microscopy in WT and pbr1-8 cells at the start of treatment with sublethal and lethal concentrations of anidulafungin, caspofungin, and micafungin. In WT, sublethal concentrations of the three drugs caused abundant cell death that was either suppressed (anidulafungin and micafungin) or greatly reduced (caspofungin) in pbr1-8 cells. Interestingly, the lethal concentrations induced differential phenotypes depending on the echinocandin used. Anidulafungin and caspofungin were mostly fungistatic, heavily impairing cytokinesis progression in both WT and pbr1-8. As with sublethal concentrations, lethal concentrations of micafungin were primarily fungicidal in WT cells, causing cell lysis without impairing cytokinesis. The lytic phenotype was suppressed again in pbr1-8 cells. Our results suggest that micafungin always exerts its fungicidal effect by solely inhibiting Bgs4. In contrast, lethal concentrations of anidulafungin and caspofungin cause an early cytokinesis arrest, probably by the combined inhibition of several GSs.

9.
Microb Cell Fact ; 20(1): 126, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217291

RESUMO

BACKGROUND: The fungal cell wall is an essential and robust external structure that protects the cell from the environment. It is mainly composed of polysaccharides with different functions, some of which are necessary for cell integrity. Thus, the process of fractionation and analysis of cell wall polysaccharides is useful for studying the function and relevance of each polysaccharide, as well as for developing a variety of practical and commercial applications. This method can be used to study the mechanisms that regulate cell morphogenesis and integrity, giving rise to information that could be applied in the design of new antifungal drugs. Nonetheless, for this method to be reliable, the availability of trustworthy commercial recombinant cell wall degrading enzymes with non-contaminating activities is vital. RESULTS: Here we examined the efficiency and reproducibility of 12 recombinant endo-ß(1,3)-D-glucanases for specifically degrading the cell wall ß(1,3)-D-glucan by using a fast and reliable protocol of fractionation and analysis of the fission yeast cell wall. This protocol combines enzymatic and chemical degradation to fractionate the cell wall into the four main polymers: galactomannoproteins, α-glucan, ß(1,3)-D-glucan and ß(1,6)-D-glucan. We found that the GH16 endo-ß(1,3)-D-glucanase PfLam16A from Pyrococcus furiosus was able to completely and reproducibly degrade ß(1,3)-D-glucan without causing the release of other polymers. The cell wall degradation caused by PfLam16A was similar to that of Quantazyme, a recombinant endo-ß(1,3)-D-glucanase no longer commercially available. Moreover, other recombinant ß(1,3)-D-glucanases caused either incomplete or excessive degradation, suggesting deficient access to the substrate or release of other polysaccharides. CONCLUSIONS: The discovery of a reliable and efficient recombinant endo-ß(1,3)-D-glucanase, capable of replacing the previously mentioned enzyme, will be useful for carrying out studies requiring the digestion of the fungal cell wall ß(1,3)-D-glucan. This new commercial endo-ß(1,3)-D-glucanase will allow the study of the cell wall composition under different conditions, along the cell cycle, in response to environmental changes or in cell wall mutants. Furthermore, this enzyme will also be greatly valuable for other practical and commercial applications such as genome research, chromosomes extraction, cell transformation, protoplast formation, cell fusion, cell disruption, industrial processes and studies of new antifungals that specifically target cell wall synthesis.


Assuntos
Parede Celular/metabolismo , Glucana Endo-1,3-beta-D-Glucosidase/metabolismo , Schizosaccharomyces/metabolismo , Schizosaccharomyces/ultraestrutura , Parede Celular/química , Glucana Endo-1,3-beta-D-Glucosidase/genética , Proteínas Recombinantes/metabolismo , Schizosaccharomyces/química , beta-Glucanas/metabolismo
10.
J. inborn errors metab. screen ; 9: e20210009, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1250216

RESUMO

ABSTRACT Neuronal Ceroid Lipofuscinosis (NCL) refers to a group of inherited lysosomal storage disorders characterized by the intracellular accumulation of ceroid-lipofuscin compounds and neurodegeneration. Fourteen genes are currently recognized with disease-causing DNA variants: PPT1/CLN1, TPP1/CLN2, CLN3, DNAJC5/CLN4, CLN5, CLN6, MFSD8/CLN7, CLN8, CTSD/CN10, GRN/CLN11, ATP13A2/CLN12, CTSF/CLN13, KCTD7/CLN14, TBCK/CLN15. In the frame of the Cordoba cohort, we studied N=51 cases. The aim of this paper is the observational and retrospective analysis of the "atypical" phenotypes. PCR-Sanger sequencing and/or massive exome sequencing were used as a screening methodology. One CLN1 subject showed an atypical prolonged (P) phenotype with null PPT1 activity and a heterozygous compound genotype: E5 c.451C>T, p.Arg151*/g.6302T>G (I3 c.363-3T>G). Other 11 CLN2 individuals (except one girl) showed TPP1 activity decreased to around 10% of the minimum value of the reference interval in leukocytes and saliva. The DNA variants E7 c.827A>T, p.Asp276Val and I7 c.887-10A>G were the most prevalent. One CLN8 individual showed an atypical congenital phenotype with a heterozygous combination of DNA variants: E2 c.1A>G, p.?/E3 c.792C>G, p.Asn264Lys. Massive sequencing was installed as a screening methodology for the precision diagnosis of atypical CLN1, CLN2, and CLN8 phenotypes. A genetic/phenotypic local registry is under construction.

11.
J Cell Biol ; 218(12): 4171-4194, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31597680

RESUMO

In fission yeast, cytokinesis requires a contractile actomyosin ring (CR) coupled to membrane and septum ingression. Septation proceeds in two phases. In anaphase B, the septum ingresses slowly. During telophase, the ingression rate increases, and the CR becomes dispensable. Here, we explore the relationship between the CR and septation by analyzing septum ultrastructure, ingression, and septation proteins in cells lacking F-actin. We show that the two phases of septation correlate with septum maturation and the response of cells to F-actin removal. During the first phase, the septum is immature and, following F-actin removal, rapidly loses the Bgs1 glucan synthase from the membrane edge and fails to ingress. During the second phase, the rapidly ingressing mature septum can maintain a Bgs1 ring and septum ingression without F-actin, but ingression becomes Cdc42 and exocyst dependent. Our results provide new insights into fungal cytokinesis and reveal the dual function of CR as an essential landmark for the concentration of Bgs1 and a contractile structure that maintains septum shape and synthesis.


Assuntos
Actinas/metabolismo , Glucosiltransferases/metabolismo , Schizosaccharomyces/citologia , Proteína cdc42 de Saccharomyces cerevisiae de Ligação ao GTP/metabolismo , Citoesqueleto de Actina/metabolismo , Actomiosina/metabolismo , Anáfase , Membrana Celular/metabolismo , Parede Celular/metabolismo , Citocinese , Proteínas do Citoesqueleto/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo II/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Telófase
12.
Sensors (Basel) ; 19(17)2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31480415

RESUMO

Three microwave sensors are used to track the glucose level of different human blood plasma solutions. In this paper, the sensors are evaluated as glucose trackers in a context close to real human blood. Different plasma solutions sets were prepared from a human blood sample at several added glucose concentrations up to 10 wt%, adding also ascorbic acid and lactic acid at different concentrations. The experimental results for the different sensors/solutions combinations are presented in this work. The sensors show good performance and linearity as glucose level retrievers, although the sensitivities change as the rest of components vary. Different sensor behaviors depending upon the concentrations of glucose and other components are identified and characterized. The results obtained in terms of sensitivity are coherent with previous works, highlighting the contribution of glucose to the dielectric losses of the solution. The results are also consistent with the frequency evolution of the electromagnetic signature of glucose found in the literature, and are helpful for selecting frequency bands for sensing purposes and envisioning future approaches to the challenging measurement in real biological contexts. Discussion of the implications of the results and guidelines for further research and development of more accurate sensors is offered.


Assuntos
Técnicas Biossensoriais/métodos , Glicemia/análise , Micro-Ondas , Humanos
13.
Med Biol Eng Comput ; 57(11): 2389-2405, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31473945

RESUMO

Self-management of blood glucose level is part and parcel of diabetes treatment, which involves invasive, painful, and uncomfortable methods. A proper non-invasive blood glucose monitor (NIBGM) is therefore desirable to deal better with it. Microwave resonators can potentially be used for such a purpose. Following the positive results from an in vitro previous work, a portable device based upon a microwave resonator was developed and assessed in a multicenter proof of concept. Its electrical response was analyzed when an individual's tongue was placed onto it. The study was performed with 352 individuals during their oral glucose tolerance tests, having four measurements per individual. The findings revealed that the accuracy must be improved before the diabetes community can make real use of the device. However, the relationship between the measuring parameter and the individual's blood glucose level is coherent with that from previous works, although with higher data dispersion. This is reflected in correlation coefficients between glycemia and the measuring magnitude consistently negative, although small, for the different datasets analyzed. Further research is proposed, focused on system improvements, individual calibration, and multitechnology approach. The study of the influence of other blood components different to glucose is also advised. Graphical abstract.


Assuntos
Automonitorização da Glicemia/instrumentação , Automonitorização da Glicemia/métodos , Adulto , Calibragem , Desenho de Equipamento , Estudos de Viabilidade , Teste de Tolerância a Glucose , Humanos , Micro-Ondas , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Língua/química , Adulto Jovem
14.
Biotechnol Adv ; 37(6): 107352, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797093

RESUMO

In the past three decades invasive mycoses have globally emerged as a persistent source of healthcare-associated infections. The cell wall surrounding the fungal cell opposes the turgor pressure that otherwise could produce cell lysis. Thus, the cell wall is essential for maintaining fungal cell shape and integrity. Given that this structure is absent in host mammalian cells, it stands as an important target when developing selective compounds for the treatment of fungal infections. Consequently, treatment with echinocandins, a family of antifungal agents that specifically inhibits the biosynthesis of cell wall (1-3)ß-D-glucan, has been established as an alternative and effective antifungal therapy. However, the existence of many pathogenic fungi resistant to single or multiple antifungal families, together with the limited arsenal of available antifungal compounds, critically affects the effectiveness of treatments against these life-threatening infections. Thus, new antifungal therapies are required. Here we review the fungal cell wall and its relevance in biotechnology as a target for the development of new antifungal compounds, disclosing the most promising cell wall inhibitors that are currently in experimental or clinical development for the treatment of some invasive mycoses.


Assuntos
Parede Celular , Micoses , Animais , Antifúngicos , Equinocandinas , Fungos
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 1115-1118, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946089

RESUMO

A portable device for noninvasive blood glucose monitoring is presented. The device is based on a microwave open-loop microstrip resonator, acting as glucose sensor, following the results of a previous study. This work shows the design and development of the driving electronics, signal generation system, data processing, measurement setup and graphical user interface, to integrate the resonator into a device suitable for further experimentation in clinical scenarios. The measurement principle relies in the idea of relating the unloaded Q factor to the user's blood glucose level. An initial assessment is shown, whose results highlight some successful cases of blood glucose level tracking, and indicate the need for further research in clinical scenarios.


Assuntos
Automonitorização da Glicemia , Glicemia , Micro-Ondas , Automonitorização da Glicemia/métodos , Eletrônica
16.
Pain ; 159(8): 1607-1620, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29677019

RESUMO

The latent sensitization model of chronic pain reveals that recovery from some types of long-term hyperalgesia is an altered state in which nociceptive sensitization persists but is suppressed by the ongoing activity of analgesic receptors such as µ-opioid receptors (MORs). To determine whether these MORs are the ones present in nociceptive afferents, we bred mice expressing Cre-recombinase under the Nav1.8 channel promoter (Nav1.8cre) with MOR-floxed mice (flMOR). These Nav1.8cre/flMOR mice had reduced MOR expression in primary afferents, as revealed by quantitative PCR, in situ hybridization, and immunofluorescence colocalization with the neuropeptide calcitonin gene-related peptide. We then studied the recovery from chronic pain of these mice and their flMOR littermates. When Nav1.8cre/flMOR mice were injected in the paw with complete Freund adjuvant they developed mechanical hyperalgesia that persisted for more than 2 months, whereas the responses of flMOR mice returned to baseline after 3 weeks. We then used the inverse agonist naltrexone to assess ongoing MOR activity. Naltrexone produced a robust reinstatement of hyperalgesia in control flMOR mice, but produced no effect in the Nav1.8/flMOR males and a weak reinstatement of hyperalgesia in Nav1.8/flMOR females. Naltrexone also reinstated swelling of the hind paw in flMOR mice and female Nav1.8cre/flMOR mice, but not male Nav1.8cre/flMOR mice. The MOR agonist DAMGO inhibited substance P release in flMOR mice but not Nav1.8cre/flMOR mice, demonstrating a loss of MOR function at the central terminals of primary afferents. We conclude that MORs in nociceptive afferents mediate an ongoing suppression of hyperalgesia to produce remission from chronic pain.


Assuntos
Dor Crônica/metabolismo , Hiperalgesia/metabolismo , Neurônios Aferentes/metabolismo , Receptores Opioides mu/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Medição da Dor , Substância P/metabolismo
17.
J Poult Sci ; 55(1): 38-46, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32055154

RESUMO

This study was conducted to evaluate the effect of Saccharomyces cerevisiae yeast cell walls (YCWs) in diets with low doses of aflatoxin B1 (AFB1) and ochratoxin A (OTA), alone or in combination, on broiler performance and immune response. A total of 210 male broilers aged 1-21 days were used. Broilers were completely randomized into seven treatments with five replicates of six broilers each, as follows: 1) control diet; 2) control + 350 µg/kg AFB1; 3) Control + 350 µg/kg OTA; 4) Control + 350 µg/kg AFB1 and 350 µg/kg OTA; 5) Control + 350 µg/kg AFB1 and 1.5 kg/ton YCW; 6) control + 350 µg/kg OTA and 1.5 kg/ton YCW; 7) control + 350 µg/kg AFB1, 350 µg/kg OTA, and 1.5 kg/ton YCW. The broilers were housed under environmentally controlled conditions in Petersime battery cages. Weight gain, feed intake, and feed conversion index were measured. The relative weights of the thymus, spleen, and bursa of Fabricius (BF) were evaluated. The local immune response was assessed by quantifying the level of intestinal immunoglobulin A (IgA). The cellular immune response was evaluated using a delayed hypersensitivity test. Hemograms and blood cell counts were also performed. The results showed that mycotoxins decreased performance and reduced the immune response (p<0.05) of broilers. Weight gain and feed conversion improved in the groups receiving YCWs. The YCWs increased (p<0.05) intestinal IgAs and the cellular immune response (p<0.05). The addition of YCWs also affected the relative weight of the thymus, spleen, and BF (p<0.05), and the leukocyte, lymphocyte, and heterophil counts (p<0.05). The addition of YCWs can be an alternative to counterage the negative effect of low doses of AFB1 and OTA in broilers diets.

18.
J Neurosci ; 36(1): 204-21, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26740662

RESUMO

Many chronic pain disorders alternate between bouts of pain and periods of remission. The latent sensitization model reproduces this in rodents by showing that the apparent recovery ("remission") from inflammatory or neuropathic pain can be reversed by opioid antagonists. Therefore, this remission represents an opioid receptor-mediated suppression of a sustained hyperalgesic state. To identify the receptors involved, we induced latent sensitization in mice and rats by injecting complete Freund's adjuvant (CFA) in the hindpaw. In WT mice, responses to mechanical stimulation returned to baseline 3 weeks after CFA. In µ-opioid receptor (MOR) knock-out (KO) mice, responses did not return to baseline but partially recovered from peak hyperalgesia. Antagonists of α2A-adrenergic and δ-opioid receptors reinstated hyperalgesia in WT mice and abolished the partial recovery from hyperalgesia in MOR KO mice. In rats, antagonists of α2A adrenergic and µ-, δ-, and κ-opioid receptors reinstated hyperalgesia during remission from CFA-induced hyperalgesia. Therefore, these four receptors suppress hyperalgesia in latent sensitization. We further demonstrated that suppression of hyperalgesia by MORs was due to their constitutive activity because of the following: (1) CFA-induced hyperalgesia was reinstated by the MOR inverse agonist naltrexone (NTX), but not by its neutral antagonist 6ß-naltrexol; (2) pro-enkephalin, pro-opiomelanocortin, and pro-dynorphin KO mice showed recovery from hyperalgesia and reinstatement by NTX; (3) there was no MOR internalization during remission; (4) MORs immunoprecipitated from the spinal cord during remission had increased Ser(375) phosphorylation; and (5) electrophysiology recordings from dorsal root ganglion neurons collected during remission showed constitutive MOR inhibition of calcium channels. SIGNIFICANCE STATEMENT: Chronic pain causes extreme suffering to millions of people, but its mechanisms remain to be unraveled. Latent sensitization is a phenomenon studied in rodents that has many key features of chronic pain: it is initiated by a variety of noxious stimuli, has indefinite duration, and pain appears in episodes that can be triggered by stress. Here, we show that, during latent sensitization, there is a sustained state of pain hypersensitivity that is continuously suppressed by the activation of µ-, δ-, and κ-opioid receptors and by adrenergic α2A receptors in the spinal cord. Furthermore, we show that the activation of µ-opioid receptors is not due to the release of endogenous opioids, but rather to its ligand-independent constitutive activity.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Hiperalgesia/prevenção & controle , Hiperalgesia/fisiopatologia , Antagonistas de Entorpecentes/administração & dosagem , Receptores Adrenérgicos alfa 2/metabolismo , Receptores Opioides/metabolismo , Animais , Adjuvante de Freund , Hiperalgesia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Medição da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Resultado do Tratamento
19.
Methods Mol Biol ; 1369: 73-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26519306

RESUMO

Fungal cleavage furrow formation during cytokinesis relays in the coordinated contraction of an actomyosin-based ring and the centripetal synthesis of both new plasma membrane and a special wall structure named division septum. Through transmission electron microscopy, the septum exhibits a three-layered structure with a central primary septum, flanked at both sides by the secondary septum. In contrast to the chitinous primary septum present in most of fungi, the fission yeast Schizosaccharomyces pombe does not contain chitin, instead it divides through the formation of a linear ß(1,3)glucan-rich primary septum, which has been shown to be specifically stained by the fluorochrome Calcofluor white. Recent findings in S. pombe have revealed the importance of septum synthesis for the steady contraction of the ring during cytokinesis. Therefore, to study the molecular mechanisms that connect the extracellular septum wall with the other components of the cytokinetic machinery located in the plasma membrane and cytoplasm, new experimental approaches are needed. Here we describe the methods developed to image the septum structure by fluorescence microscopy, with a special focus in the analysis of septum progression by the use of time-lapse microscopy.


Assuntos
Parede Celular/metabolismo , Citocinese , Microscopia de Fluorescência , Schizosaccharomyces/fisiologia , Microscopia de Fluorescência/métodos , Imagem com Lapso de Tempo/métodos
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 4792-4795, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28269342

RESUMO

New communication technologies allow us developing useful and more practical medical applications, in particular for ambulatory monitoring. NFC communication has the advantages of low powering and low influence range area, what makes this technology suitable for health applications. This work presents an explanation of the design process of planar NFC antennas in a wearable biopatch. The problem of optimizing the communication distance is addressed. Design of a biopatch for continuous temperature monitoring and experimental results obtained wearing this biopatch during daily activities are presented.


Assuntos
Temperatura Corporal , Desenho de Equipamento , Monitorização Ambulatorial/instrumentação , Redes de Comunicação de Computadores , Impedância Elétrica , Fontes de Energia Elétrica , Eletrônica , Humanos , Software , Telemetria , Termômetros
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