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1.
J Immunol ; 211(5): 735-742, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37466381

RESUMO

Tumor-infiltrating lymphocyte (TIL) adoptive cell therapy is effective in treating malignant melanoma, but its success relies on the adequate ex vivo expansion of TIL. To assess correlates of TIL expansion, CD4+ and CD8+ TIL were analyzed by RNA sequencing (RNA-seq) and chromatin immunoprecipitation sequencing of acetylated histone 3. Patients were grouped into "TIL high" and "TIL low" based on division at the median number of TIL infused. Greater numbers of TIL infused correlated with longer overall survival, and increased frequencies of CD4+ cells infused were negatively correlated with the number of TIL infused. RNA-seq analysis of CD4+ TIL showed increases in Th2/Th17/regulatory T cell-related transcripts and pathways in the TIL-low group. Analysis of a public single-cell RNA-seq dataset validated findings that increased frequencies of CD4+ cells were negatively correlated with the number of TIL infused. TIL-low patients had significantly increased frequencies of CD4+ cells expressing ETS2 and OSM and trended toward increased expression of TNFRSF18.


Assuntos
Linfócitos do Interstício Tumoral , Melanoma , Humanos , Linfócitos do Interstício Tumoral/patologia , Imunoterapia Adotiva , Interleucina-2 , Melanoma/terapia , Melanoma/patologia , Fenótipo
2.
Environ Sci Technol ; 57(13): 5180-5189, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36944351

RESUMO

Environmental risks from plant protection products (PPPs) need to be assessed to ensure safe use. The risk assessments are generally carried out using the common vole as a focal species with conservative theoretical estimates of external exposure. These are then compared to dose-related toxicity endpoints established in toxicity studies, often with laboratory species. The aim of the present study was to determine the actual internal dosimetry of PPPs' active ingredients (AIs) in a population of common voles to provide the basis for informed higher tier risk assessment. As a proof of concept, two fungicidal AIs (fludioxonil and cyprodinil) were investigated using a range of application methodologies. Individuals were treated using oral gavage application (AI dose: 100/200 mg/kg) and fed treated grass (AI sprayed at 2 kg/ha) under laboratory, semi-natural, and natural conditions. Our results show that demographic factors play a significant role in the individual residue profile and that age structure is a key aspect that determines the overall exposure risk of a population. These results are consistent from laboratory to field conditions. Future approaches could establish dose-residue relationships that are reflective of natural food intake rates in wild common vole populations in the risk assessment of PPPs.


Assuntos
Arvicolinae , Humanos , Animais , Demografia
3.
Int J Sports Med ; 44(3): 184-191, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35777726

RESUMO

The purpose of this study was to assess the reliability of blood biomarkers that can signify exercise-induced heat stress in hot conditions. Fourteen males completed two heat stress tests separated by 5-7 days. Venous blood was drawn pre- and post- heat stress for the concentration of normetanephrine, metanephrine, serum osmolality, copeptin, kidney-injury molecule 1, and neutrophil gelatinase-associated lipocalin. No biomarker, except copeptin, displayed systematic trial order bias (p≥0.05). Normetanephrine, copeptin and neutrophil gelatinase-associated lipocalin presented acceptable reliability (CV range: 0.9-14.3%), while greater variability was present in metanephrine, osmolality and kidney-injury molecule 1 (CV range: 28.6-43.2%). Normetanephrine exhibited the largest increase (p<0.001) in response to heat stress (trial 1=1048±461 pmol. L-1; trial 2=1067±408 pmol. L-1), whilst kidney-injury molecule 1 presented trivial changes (trial 1=-4±20 ng. L-1; trial 2=2 ± 16 ng. L-1, p>0.05). Normetanephrine, copeptin, and neutrophil gelatinase-associated lipocalin demonstrated good reliability and sensitivity to an acute bout of heat stress. These biomarkers may be suitable for application in laboratory and field research to understand the efficacy of interventions that can attenuate the risk of thermal injury whilst exercising in the heat.


Assuntos
Transtornos de Estresse por Calor , Normetanefrina , Masculino , Humanos , Lipocalina-2 , Metanefrina , Reprodutibilidade dos Testes , Biomarcadores , Estresse Fisiológico
4.
Eur J Orthop Surg Traumatol ; 33(7): 2995-2999, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36934360

RESUMO

PURPOSE: Carpal tunnel (CT) syndrome continues to be a commonly treated hand pathology. We aimed to evaluate several CT injection techniques for (1) spatial accuracy within the CT and (2) risk of median nerve (MN) injury. Our purpose was to evaluate for any significant differences in accuracy of needle placement within the carpal tunnel and final distance between the needle tip and the MN with each technique. METHODS: Fifteen fresh frozen cadaveric arms were used for this study. Six different injection techniques for CT injection were performed on each specimen, including palmaris longus, ulnar to flexor carpi radialis, trans-flexor carpi radialis, volar radial, volar ulnar, and direct through the palm techniques. After needle placement, a standard open CT release was performed to assess for accuracy of placement within the CT and measure needle position in relation to the MN and other anatomic structures. RESULTS: Accurate intra-CT needle placement was seen in 91% of injections. While there was no significant difference between injection techniques for distance to nearest tendon (p = 0.1531), the trans-flexor carpi radialis (tFCR), volar radial (VR), and volar ulnar (VU) techniques consistently provided the greatest intra-CT distance from needle tip to median nerve (p = 0.0019). The least incidence of intraneural needle placement was found with the tFCR and VR approaches. CONCLUSION: All six injection techniques reliably enter the CT space. The lowest risk to the MN was found with tFCR and VR techniques, and we recommend these techniques for safe and effective needle placement to avoid iatrogenic intraneural injection. LEVEL OF EVIDENCE: Level V: Cadaveric Study.


Assuntos
Síndrome do Túnel Carpal , Nervo Mediano , Humanos , Nervo Mediano/diagnóstico por imagem , Nervo Mediano/lesões , Nervo Mediano/patologia , Síndrome do Túnel Carpal/cirurgia , Punho , Antebraço , Cadáver
5.
Microbiology (Reading) ; 168(9)2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36099016

RESUMO

Traditional food processes can utilize bacteria to promote positive organoleptic qualities and increase shelf life. Wiltshire curing has a vital bacterial component that has not been fully investigated from a microbial perspective. During the investigation of a Wiltshire brine, a culturable novel bacterium of the genus Halomonas was identified by 16S rRNA gene (MN822133) sequencing and analysis. The isolate was confirmed as representing a novel species (Halomonas hibernica B1.N12) using a housekeeping (HK) gene phylogenetic tree reconstruction with the selected genes 16S rRNA, 23S rRNA, atpA, gyrB, rpoD and secA. The genome of the new isolate was sequenced and annotated and comparative genome analysis was conducted. Functional analysis revealed that the isolate has a unique phenotypic signature including high salt tolerance, a wide temperature growth range and substrate metabolism. Phenotypic and biochemical profiling demonstrated that H. hibernica B1.N12 possesses strong catalase activity which is an important feature for an industrial food processing bacterium, as it can promote an increased product shelf life and improve organoleptic qualities. Moreover, H. hibernica exhibits biocontrol properties based on its quorum quenching capabilities. Our work on this novel isolate advances knowledge on potential mechanistic interplays operating in complex microbial communities that mediate traditional food processes.


Assuntos
Halomonas , Técnicas de Tipagem Bacteriana , Composição de Bases , Catalase/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Ácidos Graxos/análise , Manipulação de Alimentos , Halomonas/genética , Filogenia , Percepção de Quorum , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
J Vasc Interv Radiol ; 33(3): 316-323.e4, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34800622

RESUMO

PURPOSE: To characterize the hepatic and abdominal angiographic anatomy of woodchucks and vascular changes associated with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty-nine woodchucks (23 with viral-associated HCC, 6 without) underwent multiphasic computed tomography (CT). Fourteen woodchucks (8 with HCC) also underwent diagnostic angiography. Hepatic arterial diameters were measured on the CT scans. Woodchucks were divided into 3 groups: non-tumor-bearing, largest tumor supplied by the right hepatic artery (RHA), and largest tumor supplied by the left hepatic artery (LHA). Statistical analysis with a repeated measures model was performed to determine the effects of tumor location (right, left), vessel measured (RHA, LHA), and interaction between the 2 on vessel diameter. Lobar arteries supplying HCC were compared with those that did not. RESULTS: CT anatomy and normal and variant vascular anatomy were defined. In woodchucks with HCC, LHA and RHA supplying tumors had mean diameters of 2.0 mm ± 0.3 and 1.6 mm ± 0.3 versus 1.5 mm ± 0.3 and 1.1 mm ± 0.2 for non-tumor-supplying arteries (P = .0002 and P < .0001), respectively. Lobar arteries supplying tumors were similarly ectatic. The right lateral lobe artery had the most profound increase in the mean diameter when supplying tumors, measuring 1.7 mm ± 0.1 versus 1.0 mm ± 0.1 in the non-tumor-supplying artery (P < .0001). There were no differences in the diameters of the aorta and celiac, common, and proper hepatic arteries between tumor- and non-tumor-bearing woodchucks. An angiographic atlas of the abdominal vessels was generated. CONCLUSIONS: HCC tumoral vasculature in woodchucks was ectatic compared with normal vasculature. This phenomenon recapitulates human HCC and may facilitate investigation of transcatheter and drug delivery therapies in an HCC animal model.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Abdome , Angiografia/métodos , Animais , Carcinoma Hepatocelular/patologia , Artéria Hepática/patologia , Humanos , Neoplasias Hepáticas/patologia , Marmota , Pelve
7.
Clin Auton Res ; 32(2): 131-141, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35461434

RESUMO

PURPOSE: Bolus water drinking, at room temperature, has been shown to improve orthostatic tolerance (OT), probably via sympathetic activation; however, it is not clear whether the temperature of the water bolus modifies the effect on OT or the cardiovascular responses to orthostatic stress. The aim of this study was to assess whether differing water temperature of the water bolus would alter time to presyncope and/or cardiovascular parameters during incremental orthostatic stress. METHODS: Fourteen participants underwent three head-up tilt (HUT) tests with graded lower body negative pressure (LBNP) continued until presyncope. Fifteen minutes prior to each HUT, participants drank a 500 mL bolus of water which was randomised, in single-blind crossover fashion, to either room temperature water (20 °C) (ROOM), ice-cold water (0-3 °C) (COLD) or warm water (45 °C) (WARM). Cardiovascular parameters were monitored continuously. RESULTS: There was no significant difference in OT in the COLD (33 ± 3 min; p = 0.3321) and WARM (32 ± 3 min; p = 0.6764) conditions in comparison to the ROOM condition (31 ± 3 min). During the HUT tests, heart rate and cardiac output were significantly reduced (p < 0.0073), with significantly increased systolic blood pressure, stroke volume, cerebral blood flow velocity and total peripheral resistance (p < 0.0054), in the COLD compared to ROOM conditions. CONCLUSIONS: In healthy controls, bolus cold water drinking results in favourable orthostatic cardiovascular responses during HUT/LBNP without significantly altering OT. Using a cold water bolus may result in additional benefits in patients with orthostatic intolerance above those conferred by bolus water at room temperature (by ameliorating orthostatic tachycardia and enhancing vascular resistance responses). Further research in patients with orthostatic intolerance is warranted.


Assuntos
Intolerância Ortostática , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Frequência Cardíaca/fisiologia , Humanos , Pressão Negativa da Região Corporal Inferior , Intolerância Ortostática/diagnóstico , Método Simples-Cego , Síncope , Temperatura , Água/farmacologia
8.
Scand J Med Sci Sports ; 32(1): 233-241, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34597427

RESUMO

PURPOSE: This study sought to explore, for the first time, the effects of repeated maximal static and dynamic apnoeic attempts on the physiological milieu by assessing cerebral, cardiac and striatal muscle stress-related biomarkers in a group of elite breath-hold divers (EBHD). METHODS: Sixteen healthy males were recruited (EBHD = 8; controls = 8). On two separate occasions, EBHD performed two sets of five repeated maximal static apnoeas (STA) or five repeated maximal dynamic apnoeas (DYN). Controls performed a static eupnoeic protocol to negate any effects of water immersion and diurnal variation on haematology (CTL). Venous blood samples were drawn at 30, 90, and 180 min after each protocol to determine S100ß, neuron-specific enolase (NSE), myoglobin, and high sensitivity cardiac troponin T (hscTNT) concentrations. RESULTS: S100ß and myoglobin concentrations were elevated following both apnoeic interventions (p < 0.001; p ≤ 0.028, respectively) but not after CTL (p ≥ 0.348). S100ß increased from baseline (0.024 ± 0.005 µg/L) at 30 (STA, +149%, p < 0.001; DYN, +166%, p < 0.001) and 90 min (STA, +129%, p < 0.001; DYN, +132%, p = 0.008) following the last apnoeic repetition. Myoglobin was higher than baseline (22.3 ± 2.7 ng/ml) at 30 (+42%, p = 0.04), 90 (+64%, p < 0.001) and 180 min (+49%, p = 0.013) post-STA and at 90 min (+63%, p = 0.016) post-DYN. Post-apnoeic S100ß and myoglobin concentrations were higher than CTL (STA, p < 0.001; DYN, p ≤ 0.004). NSE and hscTNT did not change from basal concentrations after the apnoeic (p ≥ 0.146) nor following the eupnoeic (p ≥ 0.553) intervention. CONCLUSIONS: This study suggests that a series of repeated maximal static and dynamic apnoeas transiently disrupt the blood-brain barrier and instigate muscle injury but do not induce neuronal-parenchymal damage or myocardial damage.


Assuntos
Apneia , Mergulho , Suspensão da Respiração , Coração , Humanos , Masculino , Músculo Esquelético
9.
BMC Med Educ ; 22(1): 332, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488266

RESUMO

BACKGROUND: Microcredentials (MCs) are short courses that certify/recognise an individual's achievement of specific skills or knowledge. Schools of pharmacy could be well-placed to contribute to the continuing professional development (CPD) of pharmacists through the inclusion of MCs training in their programs. This study aimed to explore pharmacy professionals' views on the need and viability of MC courses globally. METHODS: Eleven semi-structured telephone interviews were conducted with pharmacy practitioners, policymakers, and academics across seven countries. The participants were selected using purposive sampling to explore information from varying pharmacy disciplines. Interviews were audio-recorded, transcribed verbatim, and analysed using a general inductive approach. RESULTS: Participants regarded MCs in pharmacy as an innovative idea, well-suited to the increasingly technology-driven world. They believe MCs provide easily accessible means of skills and knowledge acquisition that fulfils the needs of the pharmacy profession. MCs were also perceived as an alternative pathway of meeting the requirements of traditional CPD programmes. Many participants believe universities are well-suited to provide MCs; however, numerous challenges such as recognition, time and resources have been identified as potential barriers to enrolment and implementation. CONCLUSIONS: This study provides an insight into the views of pharmacy practitioners and academics on MCs, and their potential utility in pharmacy education and practice. The findings should help in the development of MCs that could be utilised by pharmacy practitioners around the world for CPD purposes. This study comes at a time when alternative models of teaching and learning are being explored as a direct result of the COVID-19 pandemic.


Assuntos
COVID-19 , Assistência Farmacêutica , Farmácia , COVID-19/epidemiologia , Humanos , Pandemias , Farmacêuticos
10.
Sci Eng Ethics ; 28(6): 56, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36374398

RESUMO

Following other contributions about the MAX accidents to this journal, this paper explores the role of betrayal and moral injury in safety engineering related to the U.S. federal regulator's role in approving the Boeing 737MAX-a plane involved in two crashes that together killed 346 people. It discusses the tension between humility and hubris when engineers are faced with complex systems that create ambiguity, uncertain judgements, and equivocal test results from unstructured situations. It considers the relationship between moral injury, principled outrage and rebuke when the technology ends up involved in disasters. It examines the corporate backdrop against which calls for enhanced employee voice are typically made, and argues that when engineers need to rely on various protections and moral inducements to 'speak up,' then the ethical essence of engineering-skepticism, testing, checking, and questioning-has already failed.


Assuntos
Traição , Princípios Morais , Humanos , Engenharia , Tecnologia
11.
Am J Physiol Endocrinol Metab ; 321(2): E281-E291, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34191631

RESUMO

Hypothalamic-pituitary-gonadal (HPG) axis suppression in exercising women can be caused by low energy availability (EA), but the impact of a real-world, multistressor training environment on reproductive and metabolic function is unknown. This study aimed to characterize reproductive and metabolic adaptation in women undertaking basic military training. A prospective cohort study in women undertaking 11-month initial military training (n = 47) was carried out. Dynamic low-dose 1-h gonadotrophin-releasing hormone (GnRH) tests were completed after 0 and 7 mo of training. Urine progesterone was sampled weekly throughout. Body composition (dual X-ray absorptiometry), fasting insulin resistance (homeostatic modeling assessment 2, HOMA2), leptin, sex steroids, anti-Müllerian hormone (AMH), and inhibin B were measured after 0, 7, and 11 mo with an additional assessment of body composition at 3 mo. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) responses were suppressed after 7 mo (both P < 0.001). Among noncontraceptive users (n = 20), 65% had regular (23-35 days) cycles preenrollment, falling to 24% by 7 mo of training. Of women in whom urine progesterone was measured (n = 24), 87% of cycles showed no evidence of ovulation. There was little change in AMH, LH, and estradiol, although inhibin B and FSH increased (P < 0.05). Fat mass fluctuated during training but at month 11 was unchanged from baseline. Fat-free mass did not change. Visceral adiposity, HOMA2, and leptin increased (all P < 0.001). HPG axis suppression with anovulation occurred in response to training without evidence of low EA. Increased insulin resistance may have contributed to the observed pituitary and ovarian dysfunction. Our findings are likely to represent an adaptive response of reproductive function to the multistressor nature of military training.NEW & NOTEWORTHY We characterized reproductive endocrine adaptation to prolonged arduous multistressor training in women. We identified marked suppression of hypothalamic-pituitary-gonadal (HPG) axis function during training but found no evidence of low energy availability despite high energy requirements. Our findings suggest a complex interplay of psychological and environmental stressors with suppression of the HPG axis via activation of the hypothalamic-pituitary adrenal (HPA) axis. The neuroendocrine impact of nonexercise stressors on the HPG axis during arduous training should be considered.


Assuntos
Adaptação Fisiológica , Fenômenos Reprodutivos Fisiológicos , Estresse Psicológico/metabolismo , Adulto , Composição Corporal , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Progesterona/metabolismo , Estudos Prospectivos , Adulto Jovem
12.
Nitric Oxide ; 113-114: 70-77, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051342

RESUMO

PURPOSE: The aim was to investigate the effect of dietary nitrate supplementation (in the form of beetroot juice, BRJ) for 20 days on salivary nitrite (a potential precursor of bioactive nitric oxide), exercise performance and high altitude (HA) acclimatisation in field conditions (hypobaric hypoxia). METHODS: This was a single-blinded randomised control study of 22 healthy adult participants (12 men, 10 women, mean age 28 ± 12 years) across a HA military expedition. Participants were randomised pre-ascent to receive two 70 ml dose per day of either BRJ (~12.5 mmol nitrate per day; n = 11) or non-nitrate calorie matched control (n = 11). Participants ingested supplement doses daily, beginning 3 days prior to departure and continued until the highest sleeping altitude (4800 m) reached on day 17 of the expedition. Data were collected at baseline (44 m altitude), at 2350 m (day 9), 3400 m (day 12) and 4800 m (day 17). RESULTS: BRJ enhanced the salivary levels of nitrite (p = 0.007). There was a significant decrease in peripheral oxygen saturation and there were increases in heart rate, diastolic blood pressure, and rating of perceived exertion with increasing altitude (p=<0.001). Harvard Step Test fitness scores significantly declined at 4800 m in the control group (p = 0.003) compared with baseline. In contrast, there was no decline in fitness scores at 4800 m compared with baseline (p = 0.26) in the BRJ group. Heart rate recovery speed following exercise at 4800 m was significantly prolonged in the control group (p=<0.01) but was unchanged in the BRJ group (p = 0.61). BRJ did not affect the burden of HA illness (p = 1.00). CONCLUSIONS: BRJ increases salivary nitrite levels and ameliorates the decline in fitness at altitude but does not affect the occurrence of HA illness.


Assuntos
Adaptação Fisiológica/fisiologia , Exercício Físico/fisiologia , Sucos de Frutas e Vegetais/análise , Hipóxia/sangue , Nitratos/sangue , Nitritos/sangue , Adulto , Altitude , Suplementos Nutricionais , Feminino , Humanos , Masculino , Militares , Nitratos/administração & dosagem , Nitratos/metabolismo
13.
Org Biomol Chem ; 19(1): 188-198, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33119023

RESUMO

The marine transaminase, P-ω-TA, can be employed for the transamination from 1-aminotetralins and 1-aminoindanes with differentiation of stereochemistry at both the site of reaction and at a remote stereocentre resulting in formation of ketone products with up to 93% ee. While 4-substituents are tolerated on the tetralin core, the presence of 3- or 8-substituents is not tolerated by the transaminase. In general P-ω-TA shows capacity for remote diastereoselectivity, although both the stereoselectivity and efficiency are dependent on the specific substrate structure. Optimum efficiency and selectivity are seen with 4-haloaryl-1-aminotetralins and 3-haloaryl-1-aminoindanes, which may be associated with the marine origin of this enzyme.


Assuntos
Organismos Aquáticos/enzimologia , Transaminases/metabolismo , Estereoisomerismo , Especificidade por Substrato
14.
Eur J Appl Physiol ; 121(4): 1179-1187, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33512586

RESUMO

PURPOSE: Endurance exercise and hyperthermia are associated with compromised intestinal permeability and endotoxaemia. The presence of intestinal fatty acid-binding protein (I-FABP) in the systemic circulation suggests intestinal wall damage, but this marker has not previously been used to investigate intestinal integrity after marathon running. METHODS: Twenty-four runners were recruited as controls prior to completing a standard marathon and had sequential I-FABP measurements before and on completion of the marathon, then at four and 24 h later. Eight runners incapacitated with exercise-associated collapse (EAC) with hyperthermia had I-FABP measured at the time of collapse and 1 hour later. RESULTS: I-FABP was increased immediately on completing the marathon (T0; 2593 ± 1373 ng·l-1) compared with baseline (1129 ± 493 ng·l-1; p < 0.01) in the controls, but there was no significant difference between baseline and the levels at four hours (1419 ± 1124 ng·l-1; p = 0.7), or at 24 h (1086 ± 302 ng·l-1; p = 0.5). At T0, EAC cases had a significantly higher I-FABP concentration (15,389 ± 8547 ng.l-1) compared with controls at T0 (p < 0.01), and remained higher at 1 hour after collapse (13,951 ± 10,476 ng.l-1) than the pre-race control baseline (p < 0.05). CONCLUSION: I-FABP is a recently described biomarker whose presence in the circulation is associated with intestinal wall damage. I-FABP levels increase after marathon running and increase further if the endurance exercise is associated with EAC and hyperthermia. After EAC, I-FABP remains high in the circulation for an extended period, suggesting ongoing intestinal wall stress.


Assuntos
Exaustão por Calor/fisiopatologia , Hipertermia/fisiopatologia , Mucosa Intestinal/fisiopatologia , Corrida de Maratona/fisiologia , Adulto , Biomarcadores/sangue , Proteínas de Ligação a Ácido Graxo/sangue , Feminino , Exaustão por Calor/sangue , Exaustão por Calor/etiologia , Humanos , Hipertermia/sangue , Hipertermia/etiologia , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade
15.
Microbiology (Reading) ; 166(2): 169-179, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31860435

RESUMO

In recent years, the alkyl-quinolone molecular framework has already provided a rich source of bioactivity for the development of novel anti-infective compounds. Based on the quorum-sensing signalling molecules 4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS) from the nosocomial pathogen Pseudomonas aeruginosa, modifications have been developed with markedly enhanced anti-biofilm bioactivity towards important fungal and bacterial pathogens, including Candida albicans and Aspergillus fumigatus. Here we show that antibacterial activity of HHQ against Vibrionaceae is species-specific and it requires an exquisite level of structural fidelity within the alkyl-quinolone molecular framework. Antibacterial activity was demonstrated against the serious human pathogens Vibrio vulnificus and Vibrio cholerae as well as a panel of bioluminescent squid symbiont Allivibrio fischeri isolates. In contrast, Vibrio parahaemolyticus growth and biofilm formation was unaffected in the presence of HHQ and all the structural variants tested. In general, modification to almost all of the molecule except the alkyl-chain end, led to loss of activity. This suggests that the bacteriostatic activity of HHQ requires the concerted action of the entire framework components. The only exception to this pattern was deuteration of HHQ at the C3 position. HHQ modified with a terminal alkene at the quinolone alkyl chain retained bacteriostatic activity and was also found to activate PqsR signalling comparable to the native agonist. The data from this integrated analysis provides novel insights into the structural flexibility underpinning the signalling activity of the complex alkyl-quinolone molecular communication system.


Assuntos
4-Quinolonas/química , 4-Quinolonas/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Pseudomonas aeruginosa/fisiologia , 4-Quinolonas/farmacologia , Alcenos/química , Antibacterianos/farmacologia , Antibiose , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Percepção de Quorum , Transdução de Sinais , Especificidade da Espécie , Relação Estrutura-Atividade , Vibrionaceae/classificação , Vibrionaceae/efeitos dos fármacos , Vibrionaceae/crescimento & desenvolvimento , Vibrionaceae/fisiologia
16.
Radiology ; 294(1): 149-157, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31714192

RESUMO

Background MRI performed with echo-planar imaging (EPI) sequences is sensitive to susceptibility artifacts in the presence of metallic objects, which presents a substantial barrier for performing functional MRI and diffusion tensor imaging (DTI) in patients with metallic orthodontic material and other head implants. Purpose To evaluate the ability to reduce susceptibility artifacts in healthy human participants wearing metallic orthodontic braces for two alternative approaches: T2-prepared functional MRI and diffusion-prepared DTI with three-dimensional fast gradient-echo readout. Materials and Methods In this prospective study conducted from February to September 2018, T2-prepared functional MRI and diffusion-prepared DTI were performed in healthy human participants. Removable dental braces with bonding trays were used so that MRI could be performed with braces and without braces in the same participants. Results were evaluated in regions with strong (EPI dropout regions for functional MRI and the inferior fronto-occipital fasciculus for DTI) and minimal (motor cortex for functional MRI and the posterior limb of internal capsule for DTI) susceptibility artifacts. Signal-to-noise ratio (SNR), contrast-to-noise ratio for functional MRI, apparent diffusion coefficient and fractional anisotropy for DTI, and degree of distortion (quantified with the Jaccard index, which measures the similarity of geometric shapes) were compared in regions with strong or minimal susceptibility effects between the current standard EPI sequences and the proposed alternatives by using paired t test. Results Six participants were evaluated (mean age ± standard deviation, 40 years ± 6; three women). In brain regions with strong susceptibility effects from the metallic braces, T2-prepared functional MRI showed significantly higher SNR (37.8 ± 2.4 vs 15.5 ± 5.3; P < .001) and contrast-to-noise ratio (0.83 ± 0.16 vs 0.29 ± 0.10; P < .001), whereas diffusion-prepared DTI showed higher SNR (5.8 ± 1.5 vs 3.8 ± 0.7; P = .03) than did conventional EPI methods. Apparent diffusion coefficient and fractional anisotropy were consistent with the literature. Geometric distortion was substantially reduced throughout the brain with the proposed methods (significantly higher Jaccard index, 0.95 ± 0.12 vs 0.81 ± 0.61; P < .001). Conclusion T2-prepared functional MRI and diffusion-prepared diffusion tensor imaging can acquire functional and diffusion MRI, respectively, in healthy human participants wearing metallic dental braces with less susceptibility artifacts and geometric distortion than with conventional echo-planar imaging. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Dietrich in this issue.


Assuntos
Artefatos , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Braquetes Ortodônticos , Adulto , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes
17.
J Vasc Interv Radiol ; 31(11): 1874-1885, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33129433

RESUMO

PURPOSE: To assess the feasibility of inducing vascular occlusion by application of radiofrequency (RF) energy via conductive endovascular wires or baskets. MATERIALS AND METHODS: A retrievable nitinol basket and stainless steel guidewire with a platinum tip were evaluated as conductors for endovascular application of RF energy. Tissue-mimicking thermochromic gel phantoms that change color with heating were cast with 2-, 5-, and 7-mm-diameter lumens and filled with 37 oC saline. After ablation, the phantoms were sectioned, and the thermal footprints were evaluated. Six castrated male domestic swine underwent endovascular ablation using the basket in iliac arteries and guidewires in renal arteries. Post-procedural angiography was performed, and postmortem arterial segments were resected for histopathologic analysis. RESULTS: In the phantom, the depth of thermal change in the 5- and 7-mm lumens averaged 6.3 and 6.0 mm along the basket, respectively, and in the 2- and 5-mm lumens, the depth of thermal change averaged 1.9 and 0.5 mm along the wire, respectively. In the swine, RF energy delivery led to angiographic occlusion at 12 of 13 sites. Thermal injury and occlusion were similar at the proximal, middle, and distal basket treatment zone, whereas injury and occlusion decreased from the proximal to the distal end of the 5-cm wire treatment zone. CONCLUSIONS: Endovascular delivery of RF energy via a conductive basket in medium-sized arteries or a guidewire in small arteries led to acute angiographic and histologic occlusion. The potential to induce stasis might be useful in settings where rapid occlusion is desirable.


Assuntos
Procedimentos Endovasculares/instrumentação , Artéria Ilíaca/cirurgia , Ablação por Radiofrequência/instrumentação , Artéria Renal/cirurgia , Ligas , Animais , Condutividade Elétrica , Desenho de Equipamento , Estudos de Viabilidade , Temperatura Alta , Artéria Ilíaca/patologia , Masculino , Teste de Materiais , Modelos Animais , Orquiectomia , Platina , Artéria Renal/patologia , Aço Inoxidável , Sus scrofa
18.
J Vasc Interv Radiol ; 31(5): 812-819.e1, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32107125

RESUMO

PURPOSE: To assess the feasibility of transarterial chemoembolization with drug-eluting embolic (DEE) microspheres in a woodchuck model of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Nine woodchucks were studied: 4 normal animals and 5 animals infected with woodchuck hepatitis virus in which HCC had developed. Three animals with HCC underwent multidetector CT. A 3-F sheath was introduced into the femoral artery, and the hepatic arteries were selectively catheterized with 2.0-2.4-F microcatheters. Normal animals underwent diagnostic angiography and bland embolization. Animals with HCC underwent DEE transarterial chemoembolization with 70-150-µm radiopaque microspheres loaded with 37.5 mg doxorubicin per milliliter. Cone-beam CT and multidetector CT were performed. Following euthanasia, explanted livers underwent micro-CT, histopathologic examination, and fluorescence imaging of doxorubicin. RESULTS: The tumors were hypervascular and supplied by large-caliber tortuous vessels, with arteriovenous shunts present in 2 animals. There was heterogeneous enhancement on multidetector CT with areas of necrosis. Six tumors were identified. The most common location was the right medial lobe (n = 3). Mean tumor volume was 30.7 cm3 ± 12.3. DEE chemoembolization of tumors was achieved. Excluding the 2 animals with arteriovenous shunts, the mean volume of DEE microspheres injected was 0.49 mL ± 0.17. Fluorescence imaging showed diffusion of doxorubicin from the DEE microspheres into the tumor. CONCLUSIONS: Woodchuck HCC shares imaging appearances and biologic characteristics with human HCC. Selective catheterization and DEE chemoembolization may similarly be performed. Woodchucks may be used to model interventional therapies and possibly characterize radiologic-pathologic correlations.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/terapia , Angiografia Digital , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Tomografia Computadorizada de Feixe Cônico , Modelos Animais de Doenças , Feminino , Hepatite B/complicações , Hepatite B/virologia , Vírus da Hepatite B da Marmota/patogenicidade , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Marmota , Microscopia de Fluorescência , Microesferas , Tomografia Computadorizada Multidetectores , Carga Tumoral
19.
J Phys Chem A ; 124(39): 8065-8078, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32881496

RESUMO

The prediction of crystal structures from first-principles requires highly accurate energies for large numbers of putative crystal structures. High accuracy of solid state density functional theory (DFT) calculations is often required, but hundreds or more structures can be present in the low energy region of interest, so that the associated computational costs are prohibitive. Here, we apply statistical machine learning to predict expensive hybrid functional DFT (PBE0) calculations using a multifidelity approach to re-evaluate the energies of crystal structures predicted with an inexpensive force field. The method uses an autoregressive Gaussian process, making use of less expensive GGA DFT (PBE) calculations to bridge the gap between the force field and PBE0 energies. The method is benchmarked on the crystal structure landscapes of three small, hydrogen-bonded organic molecules and shown to produce accurate predictions of energies and crystal structure ranking using small numbers of the most expensive calculations; the PBE0 energies can be predicted with errors of less than 1 kJ mol-1 with between 4.2 and 6.8% of the cost of the full calculations. As the model that we have developed is probabilistic, we discuss how the uncertainties in predicted energies impact the assessment of the energetic ranking of crystal structures.

20.
Pharmacoepidemiol Drug Saf ; 29(8): 881-889, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32476226

RESUMO

PURPOSE: Non-steroidal anti-inflammatory drugs (NSAIDs) are associated with many serious complications and they are widely used in New Zealand (NZ). However, differences in NSAID-associated risk for these complications between ethnic groups are largely unknown. We assessed ethnic disparities in risk of hospital admission for upper gastrointestinal bleeding (UGIB), heart failure, and acute kidney failure (AKF) in NZ's primary care population prescribed and dispensed NSAIDs. METHODS: Retrospective cohort study utilising national pharmaceutical dispensing and hospital admissions data 2007 to 2015. Patient follow-up included 90-day periods following the dispensing of NSAIDs. Risk for each adverse outcome in Maori, Pacific, European, and Asian patients was estimated using multivariable Poisson regression adjusting for age, sex, deprivation, comorbidity and concurrent drug use. RESULTS: 3 023 067 patients were dispensed NSAIDs between 2008 and 2015. Their total intended duration of NSAID treatment encompassed 2 353 140 patient-years. Maori, Pacific and Asian patients were younger than European patients (all P < .001). After adjusting for other risk factors, Maori (rate ratio: 2.54, 95% confidence interval: 2.23-2.90) and Pacific patients (3.17, 2.69-3.74) were more likely to be hospitalised for UGIB than Europeans (reference), and heart failure (Maori: 2.48, 2.24-2.74; Pacific: 1.97, 1.69-2.30). Risk of AKF was higher in Maori (1.46, 1.23-1.74). Higher risk for UGIB and HF in Maori and Pacific patients was most pronounced in males and patients aged <60 years. CONCLUSIONS: Inequalities exist in the incidence of serious adverse outcomes experienced by different ethnic groups in NZ while using NSAIDs. Interventions to promote safer use of these medicines are required to reduce this inequity.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Adolescente , Adulto , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etnologia , Etnicidade , Feminino , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etnologia , Disparidades em Assistência à Saúde , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Adulto Jovem
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