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1.
Braz J Biol ; 84: e280884, 2024.
Article de Anglais | MEDLINE | ID: mdl-38922194

RÉSUMÉ

Many anuran amphibians deposit their eggs in foam nests, biostructures that help protect the eggs and tadpoles from predators. Currently, there are no other identification and description studies of the cultivable microbiota role in the nests of the Leptodactylid frogs such as Physalaemus cuvieri, Leptodactylus vastus and Adenomera hylaedactyla. This study aimed to isolate and identify the culturable bacteria from these three anuran species' nests, as well as to prospect enzymes produced by this microbiota. Foam nests samples and environmental samples were diluted and viable cell count was determined. Bacterial morphotypes from foam nest samples were isolated through spread plate technique. Isolates' DNAs were extracted followed by rRNA 16S gene amplification and Sanger sequencing. To evaluate their enzymatic potential, the isolates were cultured in ATGE medium supplemented with starch (0.1% w/v), gelatin (3% w/v) and skimmed milk (1% w/v), to verify amylase and protease activity. A total of 183 bacterial morphotypes were isolated, comprising 33 bacterial genera. Proteobacteria phylum was the most abundant in all the three nests (79%). The genera Pseudomonas and Aeromonas were the most abundant taxon in P. cuvieri and L. vastus. In A. Hylaedactyla, were Enterobacter and Bacillus. Regarding enzymatic activities, 130 isolates displayed protease activity and 45 isolates were positive for amylase activity. Our results provide unprecedented information concerning culturable bacterial microbiota of the foam nests of the Leptodactylid frogs, as well as their potential for biomolecules of biotechnological interest.


Sujet(s)
Anura , Bactéries , Animaux , Anura/microbiologie , Bactéries/classification , Bactéries/isolement et purification , ARN ribosomique 16S/génétique , Comportement de nidification/physiologie , Microbiote , ADN bactérien/analyse
2.
Article de Anglais | MEDLINE | ID: mdl-38806860

RÉSUMÉ

Mucormycosis is an extremely aggressive fungal disease with a high mortality rate, especially in people with compromised immune systems. Most cases of mucormycosis are caused by the fungus Rhizopus oryzae. The treatments used are based on high doses of antifungals, associated with surgical resections, when it is possible. However, even with this aggressive treatment, the estimated attributable mortality rate is high. There is therefore a need to develop adjuvant treatments. Photodynamic Inactivation (PDI) may be an auxiliary therapeutic option for mucormycosis. Due to the lack of reports in the literature on the morphology and photodynamic inactivation of R. oryzae, characterization of the fungus using Confocal Microscopy and Transmission Electron Microscopy, and different protocols using Photodithazine® (PDZ), a chlorin e6 compound, as a photosensitizer, were performed. The fungus growth rate under different concentrations and incubation times of the photosensitizer and its association with the surfactant Sodium Dodecyl Sulphate (SDS) was evaluated. For the hyphae, both in the light and dark phases, in the protocols using only PDZ, no effective photodynamic response was observed. Meanwhile with the combination of SDS 0.05% and PDZ, inhibition growth rates of 98% and 72% were achieved for the white and black phase, respectively. In the conidia phase, only a 1.7 log10 reduction of the infective spores was observed. High concentration of melanin and the complex and resistant structures, especially at the black phase, results in a high limitation of the PDI inactivation response. The combined use of the SDS resulted in an improved response, when compared to the one obtained with the amphotericin B treatment.

3.
Sci Rep ; 14(1): 9156, 2024 04 21.
Article de Anglais | MEDLINE | ID: mdl-38644369

RÉSUMÉ

Intervertebral Disc (IVD) degeneration has been associated with a chronic inflammatory response, but knowledge on the contribution of distinct IVD cells, namely CD44, to the progression of IVD degeneration remains elusive. Here, bovine nucleus pulposus (NP) CD44 cells were sorted and compared by gene expression and proteomics with the negative counterpart. NP cells were then stimulated with IL-1b (10 ng/ml) and dynamics of CD44 gene and protein expression was analyzed upon pro-inflammatory treatment. The results emphasize that CD44 has a multidimensional functional role in IVD metabolism, ECM synthesis and production of neuropermissive factors. CD44 widespread expression in NP was partially associated with CD14 and CD45, resulting in the identification of distinct cell subsets. In conclusion, this study points out CD44 and CD44-based cell subsets as relevant targets in the modulation of the IVD pro-inflammatory/degenerative cascade.


Sujet(s)
Antigènes CD44 , Inflammation , Dégénérescence de disque intervertébral , Nucleus pulposus , Animaux , Bovins , Nucleus pulposus/métabolisme , Nucleus pulposus/anatomopathologie , Antigènes CD44/métabolisme , Antigènes CD44/génétique , Inflammation/métabolisme , Inflammation/anatomopathologie , Dégénérescence de disque intervertébral/métabolisme , Dégénérescence de disque intervertébral/anatomopathologie , Cellules cultivées , Interleukine-1 bêta/métabolisme , Protéomique/méthodes
4.
J Neurosci ; 44(11)2024 Mar 13.
Article de Anglais | MEDLINE | ID: mdl-38479812

RÉSUMÉ

The axon is a neuronal structure capable of processing, encoding, and transmitting information. This assessment contrasts with a limiting, but deeply rooted, perspective where the axon functions solely as a transmission cable of somatodendritic activity, sending signals in the form of stereotypical action potentials. This perspective arose, at least partially, because of the technical difficulties in probing axons: their extreme length-to-diameter ratio and intricate growth paths preclude the study of their dynamics through traditional techniques. Recent findings are challenging this view and revealing a much larger repertoire of axonal computations. Axons display complex signaling processes and structure-function relationships, which can be modulated via diverse activity-dependent mechanisms. Additionally, axons can exhibit patterns of activity that are dramatically different from those of their corresponding soma. Not surprisingly, many of these recent discoveries have been driven by novel technology developments, which allow for in vitro axon electrophysiology with unprecedented spatiotemporal resolution and signal-to-noise ratio. In this review, we outline the state-of-the-art in vitro toolset for axonal electrophysiology and summarize the recent discoveries in axon function it has enabled. We also review the increasing repertoire of microtechnologies for controlling axon guidance which, in combination with the available cutting-edge electrophysiology and imaging approaches, have the potential for more controlled and high-throughput in vitro studies. We anticipate that a larger adoption of these new technologies by the neuroscience community will drive a new era of experimental opportunities in the study of axon physiology and consequently, neuronal function.


Sujet(s)
Axones , Neurones , Axones/physiologie , Potentiels d'action/physiologie , Phénomènes électrophysiologiques , Électrophysiologie
5.
Phys Rev E ; 109(1-1): 014230, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-38366434

RÉSUMÉ

Recent evidence shows that heteroclinic bifurcations in magnetic islands may be caused by the amplitude variation of resonant magnetic perturbations in tokamaks. To investigate the onset of these bifurcations, we consider a large aspect ratio tokamak with an ergodic limiter composed of two pairs of rings that create external primary perturbations with two sets of wave numbers. An individual pair produces hyperbolic and elliptic periodic points, and its associated islands, that are consistent with the Poincaré-Birkhoff fixed-point theorem. However, for two pairs producing external perturbations resonant on the same rational surface, we show that different configurations of isochronous island chains may appear on phase space according to the amplitude of the electric currents in each pair of the ergodic limiter. When one of the electric currents increases, isochronous bifurcations take place and new islands are created with the same winding number as the preceding islands. We present examples of bifurcation sequences displaying (a) direct transitions from the island chain configuration generated by one of the pairs to the configuration produced by the other pair, and (b) transitions with intermediate configurations produced by the limiter pairs coupling. Furthermore, we identify shearless bifurcations inside some isochronous islands, originating nonmonotonic local winding number profiles with associated shearless invariant curves.

6.
Sci Total Environ ; 917: 170352, 2024 Mar 20.
Article de Anglais | MEDLINE | ID: mdl-38286293

RÉSUMÉ

The contamination of indoor areas is a global health problem that can cause the dispersion of infectious diseases. In that sense, it is urgent to find new strategies applying a lower concentration of the traditional chemicals used for cleaning and disinfection. Ultraviolet radiation (UV), in particular far-UV-C (200-225 nm), has emerged as a successful, powerful, easy-to-apply, and inexpensive approach for bacterial eradication that still requires scientific assessment. This study investigated new strategies for disinfection based on far-UV-C (222 nm) combined with chlorine and mechanical cleaning, providing an innovative solution using low doses. The bactericidal activity of far-UV-C (222 nm) was tested at an intensity of irradiation from 78.4 µW/cm2 to 597.7 µW/cm2 (for 1 min) against Escherichia coli and Staphylococcus epidermidis adhered on polystyrene microtiter plates. It was further tested in combination with mechanical cleaning (ultrasounds for 1 min) and free chlorine (0.1, 0.5, and 1 mg/L for 5 min). The triple combination consisting of mechanical cleaning + free chlorine (0.5 mg/L) + far-UV-C (54 mJ/cm2) was tested against cells adhered to materials found in hospital settings and other public spaces: polyvinyl chloride (PVC), stainless steel (SS), and polyetheretherketone (PEEK). Disinfection with far-UV-C (54 mJ/cm2) and free chlorine at 0.5 mg/L for 5 min allowed a total reduction of culturable E. coli cells and a logarithmic reduction of 2.98 ± 0.03 for S. epidermidis. The triple combination of far-UV-C, free chlorine, and mechanical cleaning resulted in a total reduction of culturable cells for both adhered bacteria. Bacterial adhesion to PVC, SS, and PEEK occurred at distinct extents and influenced the bactericidal activity of the triple combination, with logarithmic reductions of up to three. The overall results highlight that, based on culturability assessment, far-UV-C (54 mJ/cm2) with chlorine (0.5 mg/L; 5 min) and mechanical cleaning (1 min) as an efficient disinfection strategy using mild conditions. The combination of culturability and viability assessment of disinfection is recommended to detect regrowth events and increase the effectiveness in microbial growth control.


Sujet(s)
Benzophénones , Escherichia coli , Polymères , Rayons ultraviolets , Staphylococcus epidermidis , Chlore/pharmacologie , Chlore/composition chimique , Désinfection/méthodes , Chlorures
9.
Theriogenology ; 215: 144-150, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38070213

RÉSUMÉ

This experiment evaluated pregnancy losses from day 30 of gestation to calving in Bos indicus females, and evaluated if serum haptoglobin concentrations during early gestation impacts subsequent pregnancy losses. A total of 4926 Nelore females were used, being 1802 nulliparous heifers inseminated as yearlings (precocious heifers), 1356 nulliparous heifers inseminated at 24 months of age (conventional heifers), 887 suckling primiparous cows, and 881 suckling multiparous cows. Cows were assigned to an ovulation synchronization + fixed-time artificial insemination (FTAI) protocol from day -11 to 0 of the experiment. Pregnancy status was verified using transrectal ultrasonography on days 30 and 60 after FTAI, via transrectal palpation on day 150 after FTAI, and according to calf birth. Blood samples were collected from all animals diagnosed pregnant on day 30 after FTAI, and analyzed for serum concentrations of haptoglobin and pregnancy associated glycoproteins (PAG). Pregnancy loss was greater (P < 0.01) from day 60-150 of gestation (10.2 %) compared with day 30-60 of gestation (6.0 %) and with day 150 of gestation to calving (7.4 %), and differed (P = 0.04) between these latter two periods. Pregnancy loss from day 30-60 of gestation did not differ (P = 0.26) among parities, whereas total pregnancy losses (day 30 to calving) were greater (P < 0.01) in precocious (28.4 %) and conventional (27.1 %) heifers compared with primiparous (16.4 %) and multiparous (13.0 %) cows. Serum PAG concentrations on day 30 after FTAI were less (P ≤ 0.03) in cows that lost the pregnancy (5.63 ng/mL) from day 30-60 of gestation, as well as those that lost the pregnancy from day 30 to calving (8.59 ng/mL) compared with cohorts that maintained the pregnancy (9.39 and 9.32 ng/mL, respectively). No differences in serum PAG concentrations on day 30 after FTAI were noted (P ≥ 0.23) according to pregnancy losses from day 60 to calving. Serum haptoglobin concentration on day 30 after FTAI also did not differ (P ≥ 0.48) between cows that maintained or lost the pregnancy. This experiment provides novel information about pregnancy losses after day 30 of gestation in B. indicus cattle, with most losses occurring as fetal mortality and not affected by systemic inflammation during early gestation. Pregnancy losses were nearly doubled in precocious and conventional heifers compared with parous cows, demonstrating the relevance of this reproductive failure to B. indicus replacement heifers.


Sujet(s)
Maladies des bovins , Haptoglobines , Grossesse , Bovins , Animaux , Femelle , Synchronisation de l'oestrus/méthodes , Avortement chez les animaux , Glycoprotéines , Parité , Insémination artificielle/médecine vétérinaire , Insémination artificielle/méthodes , Progestérone
10.
J Small Anim Pract ; 64(10): 611-618, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37572005

RÉSUMÉ

OBJECTIVE: Epilepsy is a chronic disorder, and approximately 25% to 30% of dogs with epilepsy are refractory to anti-epileptic drugs. As increased activity has been shown to reduce seizure frequency in people with epilepsy, the goal of this study was to evaluate the relationship between deviation from baseline activity and seizure incidence in dogs with epilepsy. MATERIALS AND METHODS: Activity and seizure data were obtained using a canine activity monitoring device and owner observed seizure logs in 53 dogs with idiopathic epilepsy receiving anti-epileptic drugs. Each dog's activity was individually measured, and 14-day baseline averages were calculated. Logistic regression was performed to evaluate how an observed increase in activity, ranging from 0% to 50%, above baseline activity, affects the incidence of a seizure in the following 24 hours. RESULTS: A total of 8540 activity days and 365 seizure days were used in the final analysis with an average of 11 seizures per dog (range 0 to 30 seizures). Seizure incidence was significantly more likely when activity was 10%, 20%, or 30% above baseline activity in the 24 hours before the day of a documented seizure [95% confidence interval (1.02 to 1.60), P=0.033; 95% confidence interval (1.08 to 1.80), P=0.010; 95% confidence interval (1.13 to 2.07), P=0.005, respectively]. However, when activity levels were 40% and 50% above baseline, the effect diminished (95% confidence interval (0.74 to 1.70), P=0.532; or 95% confidence interval (0.56 to 1.66), P=0.988, respectively). CLINICAL SIGNIFICANCE: Differently than in humans, this study demonstrated that a mild to moderate increase in activity resulted in a higher seizure incidence within 24 hours in dogs with epilepsy.

11.
Article de Anglais | MEDLINE | ID: mdl-37133313

RÉSUMÉ

Summary: Background. Evidence regarding drug provocation test (DPT) with chemotherapeutic agents is scarce. The aim of our study is to describe the experience of DPT in patients with a history of hypersensitivity reactions (HSRs) to antineoplastic and biological agents. Methods. This was an eight-year retrospective, observational, descriptive study of patients with a history of HSRs to chemotherapy who were submitted to DPT. Anamnesis, skin tests (ST) and DPT were analyzed. Patients with a negative DPT were submitted to at least one regular supervised administration (RSA). Patients with positive DPT or HSR during RSA were offered rapid drug desensitization (RDD). Results. A total of 54 patients were submitted to DPT. The most common suspected drugs were platins (n = 36), followed by taxanes (n = 11). Most initial reactions were classified as grade II (n = 39) according to Brown's grading system. ST with platinum (n = 35), taxanes (n = 10) and biological agents (n = 4) were negative, except for one intradermal test with paclitaxel, which was positive. A total of 64 DPTs were performed. Eleven percent of all DPTs were positive (platins (n = 6), doxorubicin (n = 1)). Of the 57 RSA with the culprit drugs, 2 were positive (platins). The diagnosis of hypersensitivity was confirmed by DPT/RSA in 9 patients. All patients with positive DPT/RSA presented HSRs of equal or less severity than the initial one. Conclusions. DPT followed by RSA allowed to exclude HSRs in 45 patients (55 culprit drugs). DPT before desensitization prevents non-hypersensitivity patients from undergoing RDD. In our study DPT was safe, all reactions were managed by an allergist.

12.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 33(2B): 99-99, abr. 2023. ilus.
Article de Portugais | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1437768

RÉSUMÉ

INTRODUÇÃO: Dados de estudos randomizados avaliando os efeitos a longo prazo da cirurgia bariátrica no controle e remissão da hipertensão (HTN) são escassos. O seguimento de curto e médio prazo do Estudo GATEWAY (1 e 3 anos) mostrou melhora significativa e remissão da hipertensão após a cirurgia bariátrica. Aqui, apresentamos os dados de acompanhamento de 5 anos deste estudo. MÉTODOS: Conduzimos um ensaio clínico randomizado, em um centro único, fase III, paralelo e aberto. Pacientes com obesidade graus 1 e 2, tomando no mínimo 2 medicamentos anti-hipertensivos em doses máximas para hipertensão, foram alocados aleatoriamente para Bypass gástrico em Y de Roux (RYGB) combinado com tratamento clínico (TC) ou TC (estilo de vida/aconselhamento nutricional) isoladamente. O desfecho primário foi a redução de pelo menos 30% do total de anti-hipertensivos, mantendo níveis controlados de pressão arterial (PA) <140/90mmHg. A análise principal seguiu o princípio de intenção de tratar modificada e os valores ausentes foram imputados com a técnica de imputação múltipla. Os desfechos secundários incluíram vários biomarcadores. RESULTADOS: Foram incluídos 100 pacientes (76% mulheres, idade: 43,8±9,2 anos, índice de massa corporal, IMC: 36,9±2,7Kg/ m2). Após 5 anos, o IMC foi de 27,8±3,8kg/m2 para RYGB e 36,4±3,9kg/m2 para TC (P<0,001). A análise de sensibilidade considerando apenas os casos com seguimento concluído (n=69) revelou resultados consistentes. Os desfechos secundários nos grupos RYGB e TC, aos 60 meses, foram: circunferência abdominal 88,05 ± 9,84cm e 109,44 ± 9,76cm (P<0,001) ; hemoglobina glicada 5,4 ± 0,43% e 5,96 ± 0,9% (P<0,001); insulina 6,41 ± 2,46mU/L e 24,65 ± 16,57mU/L (P<0,001); LDL colesterol 93.61 ± 31.06mg/dL e 109.94 ± 37.58mg/dL (P=0,022); triglicerídeos 86,76 ± 38,45mg/dL e 140,33 ± 59,11 mg/dL (P<0,001); proteína C reativa de alta sensibilidade 0,81 ± 0,76mg/L e 6,13 ± 6,22mg/L (P=0,005), respectivamente. CONCLUSÕES: A cirurgia bariátrica é uma estratégia eficaz e duradoura no controle da PA com menor número ou nenhum medicamento anti-hipertensivo e na melhora do perfil metabólico e inflamatório em pacientes com obesidade graus 1 ou 2 e hipertensão.

13.
J Assist Reprod Genet ; 40(4): 765-778, 2023 Apr.
Article de Anglais | MEDLINE | ID: mdl-36856967

RÉSUMÉ

PROPOSE: We here present a female case with primary ciliary dyskinesia (PCD) and infertility. In this report, we also present the evaluation of the patient family, including her twin sister, also with PCD and infertility. METHODS: Confirmation of the PCD clinical diagnosis was performed through assessment of cilia motility, by high-speed video microscopy (HSVM), axoneme ultrastructure, by transmission electron microscopy (TEM), and genetic characterization, by whole-exome sequence (WES). Gene expression studies used qPCR for mRNA expression and immunofluorescence to determine cell protein localization. RESULTS: We identified a homozygous nonsense variant in the DRC1 gene (NM 145038.5:c.352C>T (p.Gln118Ter)) in the female patient with PCD and infertility that fit the model of autosomal recessive genetic transmission. This variant eventually results in a dyskinetic ciliary beat with a lower frequency and a partial lack of both dynein arms as revealed by TEM analysis. Moreover, this variant implies a decrease in the expression of DRC1 mRNA and protein. Additionally, expression analysis suggested that DRC1 may interact with other DRC elements. CONCLUSIONS: Our findings suggest that the DRC1 null variant leads to PCD associated with infertility, likely caused by defects in axoneme from Fallopian tube cilia. Overall, our outcomes contribute to a better understanding of the genetic factors involved in the pathophysiology of PCD and infertility, and they highlight the interaction of different genes in the patient phenotype, which should be investigated further because it may explain the high heterogeneity observed in PCD patients.


Sujet(s)
Infertilité féminine , Syndrome de Kartagener , Humains , Femelle , Syndrome de Kartagener/génétique , Infertilité féminine/génétique , Infertilité féminine/métabolisme , Protéines/génétique , Cils vibratiles/génétique , Microscopie électronique à transmission , Mutation , Protéines associées aux microtubules/génétique
15.
Eur Ann Allergy Clin Immunol ; 55(2): 86-93, 2023 03.
Article de Anglais | MEDLINE | ID: mdl-34296844

RÉSUMÉ

Summary: Background. Lipid transfer proteins (LTP) are considered important plant food allergens in the Mediterranean area, but little is known about LTP allergy in pediatric age. Our aim was to characterize LTP allergy in children.Methods. We reviewed the clinical data from all children evaluated in our department with LTP allergy. From the 76 patients with LTP allergy, 26c hildren were included, 50% female, median age 10 years (1-17). Symptoms included urticaria in 58% (n = 15), anaphylaxis in 46% (n = 12) and OAS in 42% (n = 11). Results. Multiple reactions with different foods occurredin 69%. Cofactors were reported in 27% (n = 7). All patients had positive SPT to peach LTP extract and sIgE Pru p 3. No association between the occurrence of severe reactions and sIgE to Pru p 3 (p = 0.462), sIgE to Cor a 8(p = 0.896), SPT to peach LTP extract (p = 0.846) or the number of positive SPT to fruits/tree nuts (p = 0.972; p = 0.676) was found. Ninety-two percent of the patients tolerated fruits from Rosacea family without peel. Twelve percent reported reactions to new LTP containing foods during follow-up. LTP allergy can occur since early childhood. Conclusions. Since anaphylaxisis common and cofactors act as severity enhancers, it is fundamental to recognizeLTP allergy in children. Currently available diagnostic tests (SPT and sIgE) cannot accurately predict food tolerance or anticipate reaction severity.


Sujet(s)
Hypersensibilité alimentaire , Prunus persica , Humains , Enfant , Enfant d'âge préscolaire , Hypersensibilité alimentaire/diagnostic , Hypersensibilité alimentaire/épidémiologie , Protéines végétales , Antigènes végétaux , Immunoglobuline E/métabolisme , Allergènes , Extraits de plantes , Lipides , Tests cutanés
16.
Adv Exp Med Biol ; 1370: 1-18, 2023.
Article de Anglais | MEDLINE | ID: mdl-35699842

RÉSUMÉ

Antimicrobial resistance has become one of the major global public health issues of the twenty-first century. One of the main factors in the limited action of antimicrobials is related to the ability of microorganisms, particularly bacteria, to form biofilms. These complex and well-organized communities allow the colonizing cells to acquire survival advantages over the same cells in suspension, including antibiotic resistance. A huge percentage of bacterial infections in humans are associated with biofilms, and many of them are chronic. Therefore, there is an urgent need to develop new products effective in controlling or eradicating biofilms. Plant secondary metabolites (phytochemicals) have demonstrated their potential as antibacterials against planktonic cells and sessile communities when used alone or in synergy with other molecules. This chapter covers recent advances in the activity of phytochemicals against biofilms, particularly those formed by drug-resistant bacteria. In addition, taking into account that the extraction step is crucial for the successful development of new bioactive compounds, the use of novel solvents that increase the phytochemical effect, such as natural deep eutectic solvents (NADES), as well as the recent applications of these solvents as antimicrobials are discussed.


Sujet(s)
Anti-infectieux , Bactéries , Humains , Solvants/composition chimique , Solvants/pharmacologie , Biofilms , Anti-infectieux/pharmacologie , Antibactériens/pharmacologie , Antibactériens/composition chimique , Composés phytochimiques/pharmacologie , Composés phytochimiques/composition chimique , Extraits de plantes/pharmacologie , Extraits de plantes/composition chimique
17.
Eur Radiol ; 33(3): 1698-1706, 2023 Mar.
Article de Anglais | MEDLINE | ID: mdl-36271920

RÉSUMÉ

OBJECTIVES: To evaluate the feasibility of Doppler-ultrasound (DUS)-gated 4D flow MRI of the fetal great thoracic vessels at 3T in a clinical setting. METHODS: Sixteen consecutive fetuses (range 30+4-38+5 weeks) with (n = 11) and without (n = 5) cardiovascular anomalies underwent 4D flow MRI of the great thoracic vessels at 3T. Direct fetal cardiac gating was obtained using a MR-compatible DUS device. 4D flow MRI-based visualisation and quantification of four target regions (ascending aorta (AAo), descending aorta (DAo), main pulmonary artery (MPA), and ductus arteriosus (DA)) were performed using dedicated software. RESULTS: Fetal 4D flow MRI of the great thoracic vessels was successful in 12/16 fetuses (75%) by adopting clinical 4D flow MR protocols in combination with direct fetal cardiac DUS-gating. Four datasets were excluded due to artefacts by fetal movement or maternal breathing. 4D flow MRI-derived time-velocity curves revealed typical arterial blood flow patterns in the aorta. 4D flow quantification was achieved for the pre-defined target regions. Average velocity and flow volume were 21.1 ± 5.2 cm/s and 6.0 ± 3.1 mL/s in the AAo, 24.3 ± 6.7 cm/s and 8.4 ± 3.7 mL/s in the DAo, 21.9 ± 6.4 cm/s and 7.8 ± 4.2 mL/s in the MPA, and 23.4 ± 4.7 cm/s and 5.9 ± 3.6 mL/s in the DA, respectively. CONCLUSIONS: Combination of DUS-gating of the fetal heart and 4D flow MRI allows comprehensive visualisation and quantification of haemodynamics in the fetal great thoracic vessels. DUS-gated fetal 4D flow MRI may provide a new diagnostic approach for prenatal assessment of blood flow haemodynamics. KEY POINTS: • Fetal cardiac Doppler-ultrasound (DUS) gating and 4D flow MRI can be successfully combined. • DUS-gated fetal 4D flow MRI allowed visualisation and evaluation of streamline directionality, illustration of blood flow variations, and pulsatile arterial waveforms in the target vessels. • 4D flow MRI-based visualisation and quantification of the fetal great thoracic vessels were successful and flow metrics agreed with echocardiographic reference values.


Sujet(s)
Coeur foetal , Imagerie par résonance magnétique , Grossesse , Femelle , Humains , Études de faisabilité , Âge gestationnel , Coeur foetal/imagerie diagnostique , Coeur foetal/physiologie , Artère pulmonaire/imagerie diagnostique , Vitesse du flux sanguin/physiologie , Aorte thoracique
19.
Braz J Med Biol Res ; 55: e11831, 2022.
Article de Anglais | MEDLINE | ID: mdl-35976268

RÉSUMÉ

Candida albicans is the most frequently isolated opportunistic pathogen in the female genital tract, with 92.3% of cases in Brazil associated with vulvovaginal candidiasis (VVC). Linalool is a monoterpene compound from plants of the genera Cinnamomum, Coriandrum, Lavandula, and Citrus that has demonstrated a fungicidal effect on strains of Candida spp., but its mechanism of action is still unknown. For this purpose, broth microdilution techniques were applied, as well as molecular docking in a predictive manner for this mechanism. The main results of this study indicated that the C. albicans strains analyzed were resistant to fluconazole and sensitive to linalool at a dose of 256 µg/mL. Furthermore, the increase in the minimum inhibitory concentration (MIC) of linalool in the presence of sorbitol and ergosterol indicated that this molecule possibly affects the cell wall and plasma membrane integrity of C. albicans. Molecular docking of linalool with proteins that are key in the biosynthesis and maintenance of the cell wall and the fungal plasma membrane integrity demonstrated the possibility of linalool interacting with three important enzymes: 1,3-ß-glucan synthase, lanosterol 14α-demethylase, and Δ 14-sterol reductase. In silico analysis showed that this monoterpene has theoretical but significant oral bioavailability, low toxic potential, and high similarity to pharmaceuticals. Therefore, the findings of this study indicated that linalool probably causes damage to the cell wall and plasma membrane of C. albicans, possibly by interaction with important enzymes involved in the biosynthesis of these fungal structures, in addition to presenting low in silico toxic potential.


Sujet(s)
Candida albicans , Fluconazole , Monoterpènes acycliques , Antifongiques/pharmacologie , Résistance des champignons aux médicaments , Fluconazole/pharmacologie , Tests de sensibilité microbienne , Simulation de docking moléculaire , Monoterpènes/pharmacologie
20.
Mar Environ Res ; 180: 105707, 2022 Sep.
Article de Anglais | MEDLINE | ID: mdl-35963134

RÉSUMÉ

Shellfisheries of the intertidal and shallow subtidal infaunal bivalves Ruditapes decussatus, Ruditapes philippinarum, Venerupis corrugata and Cerastoderma edule are of great socio-economic importance (in terms of landings) in Europe, specifically in the Galician Rías Baixas (NW Spain). However, ocean warming may threaten these fisheries by modifying the geographic distribution of the species and thus affecting productive areas. The present study analysed the impact of rising ocean temperature on the geographical distribution of the thermal comfort areas of these bivalves throughout the 21st century. The Delft3D model was used to downscale climate data from CORDEX and CMIP5 and was run for July and August in three future periods (2025-2049, 2050-2074 and 2075-2099) under the RCP8.5 scenario. The areas with optimal temperature conditions for shellfish harvesting located in the middle and outer parts of the rias may increase in the near future for R. decussatus, V. corrugata and C. edule and decrease in the far future for R. philippinarum. Moreover, shellfish beds located in the shallower areas of the inner parts of the Rías Baixas could be affected by increased water temperature, reducing the productive areas of the four species by the end of the century. The projected changes in thermal condition will probably lead to changes in shellfish harvesting modality (on foot or aboard vessels) with further socio-economic consequences.


Sujet(s)
Bivalvia , Pêcheries , Animaux , Réchauffement de la planète , Fruits de mer , Espagne
SÉLECTION CITATIONS
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