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1.
Nature ; 591(7851): 599-603, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33762765

RESUMEN

Terrestrial ecosystems remove about 30 per cent of the carbon dioxide (CO2) emitted by human activities each year1, yet the persistence of this carbon sink depends partly on how plant biomass and soil organic carbon (SOC) stocks respond to future increases in atmospheric CO2 (refs. 2,3). Although plant biomass often increases in elevated CO2 (eCO2) experiments4-6, SOC has been observed to increase, remain unchanged or even decline7. The mechanisms that drive this variation across experiments remain poorly understood, creating uncertainty in climate projections8,9. Here we synthesized data from 108 eCO2 experiments and found that the effect of eCO2 on SOC stocks is best explained by a negative relationship with plant biomass: when plant biomass is strongly stimulated by eCO2, SOC storage declines; conversely, when biomass is weakly stimulated, SOC storage increases. This trade-off appears to be related to plant nutrient acquisition, in which plants increase their biomass by mining the soil for nutrients, which decreases SOC storage. We found that, overall, SOC stocks increase with eCO2 in grasslands (8 ± 2 per cent) but not in forests (0 ± 2 per cent), even though plant biomass in grasslands increase less (9 ± 3 per cent) than in forests (23 ± 2 per cent). Ecosystem models do not reproduce this trade-off, which implies that projections of SOC may need to be revised.


Asunto(s)
Dióxido de Carbono/metabolismo , Secuestro de Carbono , Plantas/metabolismo , Suelo/química , Biomasa , Pradera , Modelos Biológicos
2.
Br J Cancer ; 130(8): 1261-1268, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38383704

RESUMEN

BACKGROUND: The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population. METHODS: In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020). RESULTS: Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%. CONCLUSIONS: This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.


Asunto(s)
Cesárea , Neoplasias , Embarazo , Humanos , Femenino , Estudios Retrospectivos , Neoplasias/diagnóstico , Neoplasias/epidemiología , Neoplasias/terapia , Reino Unido/epidemiología , Nacimiento Vivo
3.
Anaesthesia ; 79(3): 278-283, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38205532

RESUMEN

The sustainable healthcare agenda has become increasingly prominent in recent years. But what does this mean for patients? In this article, we draw on our personal views and experiences as patients, carers and patient advocates, and consider the effects that efforts to improve the sustainability of healthcare may have on care quality and patient experience. We also review the small amount of existing research and policy in this area, with particular focus on documents from the National Institute for Health and Care Excellence and the Health Foundation. Based on synthesising these resources with our own experiences, we make recommendations on how to: share information with patients about how they can contribute to healthcare sustainability; offer more sustainable alternatives without pressure; account for diverse patient views on the relevance of sustainable healthcare; provide information about the impact of healthcare on the environment; involve patients and the public in leading positive change; and avoid broadening health inequalities. There is a clear need for more research and engagement to help advance our understanding and weigh up the benefits to individual patients vs. the environmental impacts on the wider population.


Asunto(s)
Atención a la Salud , Pacientes , Humanos
4.
BMC Pulm Med ; 24(1): 188, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641768

RESUMEN

BACKGROUND: Dyspnea impairs quality of life (QOL) in patients with fibrotic hypersensitivity pneumonitis (FHP). The Living with Pulmonary Fibrosis questionnaire (L-PF) assesses symptoms, their impacts and PF-related QOL in patients with any form of PF. Its scores have not undergone validation analyses in an FHP cohort. METHODS: We used data from the Pirfenidone in FHP trial to examine reliability, validity and responsiveness of the L-PF-35 Dyspnea domain score (Dyspnea) and to estimate its meaningful within-patient change (MWPC) threshold for worsening. Lack of suitable anchors precluded conducting analyses for other L-PF-35 scores. RESULTS: At baseline, Dyspnea's internal consistency (Cronbach's coefficient alpha) was 0.85; there were significant correlations with all four anchors (University of California San Diego Shortness of Breath Questionnaire scores r = 0.81, St. George's Activity domain score r = 0.82, percent predicted forced vital capacity r = 0.37, and percent predicted diffusing capacity of the lung for carbon monoxide r = 0.37). Dyspnea was significantly different between anchor subgroups (e.g., lowest percent predicted forced vital capacity (FVC%) vs. highest, 33.5 ± 18.5 vs. 11.1 ± 9.8, p = 0.01). There were significant correlations between changes in Dyspnea and changes in anchor scores at all trial time points. Longitudinal models further confirmed responsiveness. The MWPC threshold estimate for worsening was 6.6 points (range 5-8). CONCLUSION: The L-PF-35 Dyspnea domain appears to possess acceptable psychometric properties for assessing dyspnea in patients with FHP. Because instrument validation is never accomplished with one study, additional research is needed to build on the foundation these analyses provide. TRIAL REGISTRATION: The data for the analyses presented in this manuscript were generated in a trial registered on ClinicalTrials.gov; the identifier was NCT02958917.


Asunto(s)
Alveolitis Alérgica Extrínseca , Calidad de Vida , Humanos , Reproducibilidad de los Resultados , Pulmón , Disnea/etiología , Disnea/diagnóstico , Encuestas y Cuestionarios , Alveolitis Alérgica Extrínseca/complicaciones , Alveolitis Alérgica Extrínseca/tratamiento farmacológico
5.
Matern Child Health J ; 28(3): 438-469, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38372834

RESUMEN

INTRODUCTION/PURPOSE: Poverty-reduction efforts that seek to support households with children and enable healthy family functioning are vital to produce positive economic, health, developmental, and upward mobility outcomes. The Supplemental Nutrition Assistance Program (SNAP) is an effective poverty-reduction policy for individuals and families. This study investigated the non-nutritional effects that families experience when receiving SNAP benefits. METHODS: We conducted a scoping review using the PRISMA Guidelines and strategic search terms across seven databases from 01 January 2008 to 01 February 2023 (n=2456). Data extraction involved two researchers performing title-abstract reviews. Full-text articles were assessed for eligibility (n=103). Forty articles were included for data retrieval. RESULTS: SNAP positively impacts family health across the five categories of the Family Stress Model (Healthcare utilization for children and parents, Familial allocation of resources, Impact on child development and behavior, Mental health, and Abuse or neglect). DISCUSSION/CONCLUSION: SNAP is a highly effective program with growing evidence that it positively impacts family health and alleviates poverty. Four priority policy actions are discussed to overcome the unintentional barriers for SNAP: distributing benefits more than once a month; increasing SNAP benefits for recipients; softening the abrupt end of benefits when wages increase; and coordinating SNAP eligibility and enrollment with other programs.


Asunto(s)
Asistencia Alimentaria , Pobreza , Niño , Humanos , Composición Familiar , Abastecimiento de Alimentos , Conductas Relacionadas con la Salud , Estado de Salud
6.
J Dairy Sci ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38825095

RESUMEN

As the proportion of prime carcasses originating from dairy herds increases, the focus is shifting to the beef merit of the progeny from dairy herds. Several dairy cow total merit indexes include a negative weight on measures of cow size. However, there is a lack of knowledge on the impact of genetic selection, solely for lighter or smaller-sized dairy cows, on the beef performance of their progeny. Therefore, the objective of this study was to quantify the genetic correlations among cow size traits (i.e., cow body weight (BW), cow carcass weight (CW)), cow body condition score (BCS), cow carcass conformation (CC), and cow carcass fat cover (CF), as well as the correlations between these cow traits and a series of beef performance slaughter-related traits (i.e., CW, CC, CF, and age at slaughter (AS)) in their progeny. After data editing, there were 52,950 cow BW and BCS records, along with 57,509 cow carcass traits (i.e., CW, CC, and CF); carcass records from 346,350 prime animals along with AS records from 316,073 prime animals were also used. Heritability estimates ranged from moderate to high (0.18 to 0.62) for all cow and prime animal traits. The same carcass trait in cows and prime animals were strongly genetically correlated with each other (0.76 to 0.85), implying that they are influenced by very similar genomic variants. Selecting exclusively for cows with higher BCS (i.e., fatter) will, on average, produce more conformed prime animals carcasses, owing to a moderate genetic correlation (0.30) between both traits. Genetic correlations revealed that selecting exclusively for lighter BW or CW cows will, on average, result in lighter prime animal carcasses of poor CC, while also delaying slaughter age. Nonetheless, selective breeding through total merit indexes should be successful in breeding for smaller dairy cows, and desirable prime animal carcass traits concurrently, because of the non-unity genetic correlations between the cow and prime animal traits; this will help to achieve a more ethical, environmentally sustainable, and economically viable dairy-beef industry.

7.
Sex Health ; 212024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39008622

RESUMEN

Background Gonorrhoea notifications have increased substantially in Australia over the past decade. Neisseria gonorrhoeae is already highly resistant to several antibiotics and so, alternatives to first-line treatment are generally strongly discouraged. The penicillin allergy label (AL) on patient medical records has previously been shown to influence prescribing practices, to the detriment of best-practice management and antimicrobial stewardship. This study aimed to understand how the penicillin AL influences antibiotic selection for gonorrhoea treatment at Canberra Sexual Health Centre. Methods A retrospective chart audit of gonorrhoea cases treated at Canberra Sexual Health Centre between January 2020 and October 2023 (n =619 patients, n =728 cases). Antibiotic selection was assessed according to penicillin AL status. Ceftriaxone selection was assessed according to penicillin allergy severity reported in the medical records and as determined using a validated antibiotic allergy assessment tool. Results Cases with a penicillin AL were more likely to receive antibiotics other than ceftriaxone (n =7/41, 17.1%) than cases without the label (n =8/687, 1.2%, P n =28/41, 68.3%) to apply the assessment tool. Those reported as low-severity in the records were more likely to receive ceftriaxone (n =21/22, 95.5%) than those reported as moderate-high (n =7/11, 63.6%) or unreported (n =6/8, 0.75%). Conclusions Treatment of gonorrhoea in outpatient settings requires an understanding of penicillin allergy, and the ability to quickly and accurately identify penicillin-AL patients who can safely tolerate ceftriaxone. Institutionally endorsed penicillin allergy de-labelling protocols and access to easy-to-navigate prescribing advice within national sexually transmitted infection management guidelines would support this.


Asunto(s)
Antibacterianos , Ceftriaxona , Hipersensibilidad a las Drogas , Gonorrea , Penicilinas , Humanos , Gonorrea/tratamiento farmacológico , Ceftriaxona/uso terapéutico , Estudios Retrospectivos , Antibacterianos/uso terapéutico , Penicilinas/uso terapéutico , Penicilinas/efectos adversos , Femenino , Masculino , Adulto , Neisseria gonorrhoeae , Australia , Registros Médicos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Persona de Mediana Edad , Etiquetado de Medicamentos
8.
Occup Med (Lond) ; 74(1): 99-103, 2024 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-38078498

RESUMEN

BACKGROUND: As a consequence of their occupation, doctors and other healthcare workers were at higher risk of contracting coronavirus disease 2019 (COVID-19), and more likely to experience severe disease compared to the general population. However, systematic information on post-acute COVID complications in doctors is very limited. AIMS: This study aimed to determine the symptoms, perceived determinants, health and occupational impact, and consequent needs relating to post-acute COVID complications in UK doctors. METHODS: An online cross-sectional survey was distributed to UK doctors self-identifying as having Long COVID or other post-acute COVID complications. RESULTS: Of 795 responses, 603 fulfilled the inclusion criteria of being a UK-based medical doctor experiencing one or more post-acute COVID complications. Twenty-eight per cent reported a lack of adequate Respiratory Protective Equipment at the time of contracting COVID-19. Eighteen per cent of eligible respondents reported that they had been unable to return to work since acquiring COVID. CONCLUSIONS: Post-acute COVID (Long COVID) in UK doctors is a substantial burden for respondents to our questionnaire. The results indicated that insufficient respiratory protection could have contributed to occupational disease, with COVID-19 being contracted in the workplace, and resultant post-COVID complications. Although it may be too late to address the perceived determinants of inadequate protection for those already suffering with Long COVID, more investment is needed in rehabilitation and support of those afflicted.


Asunto(s)
COVID-19 , Médicos , Humanos , COVID-19/epidemiología , Síndrome Post Agudo de COVID-19 , Estudios Transversales , Reino Unido/epidemiología
9.
JAMA ; 332(5): 380-389, 2024 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-38762797

RESUMEN

Importance: Current treatments for idiopathic pulmonary fibrosis slow the rate of lung function decline, but may be associated with adverse events that affect medication adherence. In phase 2 trials, pamrevlumab (a fully human monoclonal antibody that binds to and inhibits connective tissue growth factor activity) attenuated the progression of idiopathic pulmonary fibrosis without substantial adverse events. Objective: To assess the efficacy and safety of pamrevlumab for patients with idiopathic pulmonary fibrosis. Design, Setting, and Participants: Phase 3 randomized clinical trial including 356 patients aged 40 to 85 years with idiopathic pulmonary fibrosis who were not receiving antifibrotic treatment with nintedanib or pirfenidone at enrollment. Patients were recruited from 117 sites in 9 countries between July 18, 2019, and July 29, 2022; the last follow-up encounter occurred on August 28, 2023. Interventions: Pamrevlumab (30 mg/kg administered intravenously every 3 weeks; n = 181) or placebo (n = 175) for 48 weeks. Main Outcomes and Measures: The primary outcome was absolute change in forced vital capacity (FVC) from baseline to week 48. There were 5 secondary outcomes (including time to disease progression, which was defined as a decline of ≥10% in predicted FVC or death). The exploratory outcomes included patient-reported symptoms. Adverse events were reported. Results: Among 356 patients (mean age, 70.5 years; 258 [72.5%] were men; 221 [62.1%] were White), 277 (77.8%) completed the trial. There was no significant between-group difference for absolute change in FVC from baseline to week 48 (least-squares mean, -260 mL [95% CI, -350 to -170 mL] in the pamrevlumab group vs -330 mL [95% CI, -430 to -230 mL] in the placebo group; mean between-group difference, 70 mL [95% CI, -60 to 190 mL], P = .29). There were no significant between-group differences in any of the secondary outcomes or in the patient-reported outcomes. In the pamrevlumab group, there were 160 patients (88.4%) with treatment-related adverse events and 51 patients (28.2%) with serious adverse events vs 151 (86.3%) and 60 (34.3%), respectively, in the placebo group. During the study, 23 patients died in each group (12.7% in the pamrevlumab group vs 13.1% in the placebo group). Conclusions and Relevance: Among patients with idiopathic pulmonary fibrosis treated with pamrevlumab or placebo, there was no statistically significant between-group difference for the primary outcome of absolute change in FVC from baseline to week 48. Trial Registration: ClinicalTrials.gov Identifier: NCT03955146.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Fibrosis Pulmonar Idiopática , Humanos , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Masculino , Femenino , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Persona de Mediana Edad , Anciano , Capacidad Vital , Adulto , Método Doble Ciego , Anciano de 80 o más Años , Progresión de la Enfermedad , Factor de Crecimiento del Tejido Conjuntivo
10.
J Obstet Gynaecol ; 44(1): 2375590, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39039900

RESUMEN

BACKGROUND: Operative vision can frequently be critically reduced during laparoscopic surgery by condensation and other matter accumulating on the distal laparoscope lens. By delivering saline and carbon dioxide across the lens, the OpClear system is designed to maintain operative vision without needing scope removal for lens cleaning. This study evaluates the system's efficacy in providing high-level visual acuity during laparoscopic hysterectomy while examining its utility through its impact on operative duration. METHODS: A retrospective audit compared efficacy and utility for the three years before and after the implementation of OpClear in a single unit. Thirty-three cases were reviewed pre-OpClear, while 82 cases were analysed in the post-OpClear group. All cases involved routine total laparoscopic hysterectomies (TLH) performed by the same surgeon (AT) with similar complexity levels. RESULTS: The OpClear system provided a consistently high level of visual acuity throughout the laparoscopic procedures. Scope removals, which typically result in non-productive operating time, were virtually eliminated. Consequently, in highly comparable cases, OpClear usage resulted in a 17-minute reduction in operating time over cases performed without the device. Additionally, in the OpClear group, there were trends towards reduced blood loss and shorter hospital stays, with patients in the OpClear group being discharged on first rather than second postoperatively. CONCLUSIONS: The findings of this audit suggest that the OpClear system provides continuous high-level vision during laparoscopic hysterectomy. Further, reducing periods of non-productive time associated with scope removal for cleaning resulted in shorter operating times. Thus, the system has the potential to enhance safety, improve theatre utilisation and alleviate some of the surgical stresses associated with laparoscopic surgery.


Keyhole (Laparoscopic) surgery is often better for patients than open surgery as it speeds up recovery and return to normal activities. However, despite technical advances, the surgeon's view during keyhole operations may be lost by condensation and tissue material sticking to the lens of the laparoscope, the instrument used to see inside the body. For safety, such vision loss demands that operations must be paused so the 'scope' can be removed and the lens cleaned. This may occur often during an operation, interrupting its progress. Our audit reviews OpClear, a device that cleans the lens while the scope is in the body, improving vision and reducing pauses. OpClear works by blowing gas and fluid across the lens, washing away contamination. In keyhole hysterectomy operations, OpClear maintained vision and shortened the length of operations. OpClear may lead to safer, shorter keyhole operations and help improve the efficiency of operating departments.


Asunto(s)
Histerectomía , Laparoscopía , Tempo Operativo , Agudeza Visual , Humanos , Femenino , Laparoscopía/métodos , Histerectomía/métodos , Histerectomía/efectos adversos , Estudios Retrospectivos , Persona de Mediana Edad , Adulto , Tiempo de Internación/estadística & datos numéricos , Laparoscopios
11.
Am Nat ; 202(5): E130-E146, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37963120

RESUMEN

AbstractDisease control can induce both demographic and evolutionary responses in host-parasite systems. Foreseeing the outcome of control therefore requires knowledge of the eco-evolutionary feedback between control and system. Previous work has assumed that control strategies have a homogeneous effect on the parasite population. However, this is not true when control targets those traits that confer to the parasite heterogeneous levels of resistance, which can additionally be related to other key parasite traits through evolutionary trade-offs. In this work, we develop a minimal model coupling epidemiological and evolutionary dynamics to explore possible trait-dependent effects of control strategies. In particular, we consider a parasite expressing continuous levels of a trait-determining resource exploitation and a control treatment that can be either positively or negatively correlated with that trait. We demonstrate the potential of trait-dependent control by considering that the decision maker may want to minimize both the damage caused by the disease and the use of treatment, due to possible environmental or economic costs. We identify efficient strategies showing that the optimal type of treatment depends on the amount applied. Our results pave the way for the study of control strategies based on evolutionary constraints, such as collateral sensitivity and resistance costs, which are receiving increasing attention for both public health and agricultural purposes.


Asunto(s)
Parásitos , Animales , Evolución Biológica , Interacciones Huésped-Parásitos
12.
Thorax ; 78(11): 1097-1104, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37028940

RESUMEN

BACKGROUND: Fibrotic hypersensitivity pneumonitis (FHP) is an irreversible lung disease with high morbidity and mortality. We sought to evaluate the safety and effect of pirfenidone on disease progression in such patients. METHODS: We conducted a single-centre, randomised, double-blinded, placebo-controlled trial in adults with FHP and disease progression. Patients were assigned in a 2:1 ratio to receive either oral pirfenidone (2403 mg/day) or placebo for 52 weeks. The primary end point was the mean absolute change in the per cent predicted forced vital capacity (FVC%). Secondary end points included progression-free survival (PFS, time to a relative decline ≥10% in FVC and/or diffusing capacity of the lung for carbon monoxide (DLCO), acute respiratory exacerbation, a decrease of ≥50 m in the 6 min walk distance, increase or introduction of immunosuppressive drugs or death), change in FVC slope and mean DLCO%, hospitalisations, radiological progression of lung fibrosis and safety. RESULTS: After randomising 40 patients, enrolment was interrupted by the COVID-19 pandemic. There was no significant between-group difference in FVC% at week 52 (mean difference -0.76%, 95% CI -6.34 to 4.82). Pirfenidone resulted in a lower rate of decline in the adjusted FVC% at week 26 and improved PFS (HR 0.26, 95% CI 0.12 to 0.60). Results for other secondary end points showed no significant difference between groups. No deaths occurred in the pirfenidone group and one death (respiratory) occurred in the placebo group. There were no treatment-emergent serious adverse events. CONCLUSIONS: The trial was underpowered to detect a difference in the primary end point. Pirfenidone was found to be safe and improved PFS in patients with FHP. TRIAL REGISTRATION MUMBER: NCT02958917.


Asunto(s)
Alveolitis Alérgica Extrínseca , COVID-19 , Fibrosis Pulmonar Idiopática , Adulto , Humanos , Fibrosis Pulmonar Idiopática/diagnóstico , Resultado del Tratamiento , Pandemias , Capacidad Vital , Piridonas/efectos adversos , Método Doble Ciego , Progresión de la Enfermedad , Alveolitis Alérgica Extrínseca/tratamiento farmacológico
13.
Proc Biol Sci ; 290(2001): 20230584, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37339745

RESUMEN

Temporal patterns in spawning and juvenile recruitment can have major effects on population size and the demographic structure of coral reef fishes. For harvested species, these patterns are crucial in determining stock size and optimizing management strategies such as seasonal closures. For the commercially important coral grouper (Plectropomus spp.) on the Great Barrier Reef, histological studies indicate peak spawning around the summer new moons. Here we examine the timing of spawning activity for P. maculatus in the southern Great Barrier Reef by deriving age in days for 761 juvenile fish collected between 2007 and 2022, and back-calculating settlement and spawning dates. Age-length relationships were used to estimate spawning and settlement times for a further 1002 juveniles collected over this period. Unexpectedly, our findings indicate year-round spawning activity generates distinct recruitment cohorts that span several weeks to months. Peak spawning varied between years with no clear association with environmental cues, and little to no alignment with existing seasonal fisheries closures around the new moon. Given the variability and uncertainty in peak spawning times, this fishery may benefit from additional and longer seasonal closures, or alternative fisheries management strategies, to maximize the recruitment contribution from periods of greatest reproductive success.


Asunto(s)
Antozoos , Lubina , Animales , Estaciones del Año , Peces , Arrecifes de Coral , Explotaciones Pesqueras , Envejecimiento
14.
Anaesthesia ; 78(12): 1481-1492, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37880924

RESUMEN

Cardiac surgery requiring cardiopulmonary bypass is associated with postoperative acute kidney injury and neurocognitive disorders, including delirium. Intra-operative inflammation and/or impaired tissue perfusion/oxygenation are thought to be contributors to these outcomes. It has been hypothesised that these problems may be ameliorated by the highly selective α2 -agonist, dexmedetomidine. We tested the effects of dexmedetomidine on renal and cerebral microcirculatory tissue perfusion, oxygenation and histology in a clinically relevant ovine model. Sixteen sheep were studied while conscious, after induction of anaesthesia and during 2 h of cardiopulmonary bypass. Eight sheep were allocated randomly to receive an intravenous infusion of dexmedetomidine (0.4-0.8 µg.kg-1 .h-1 ) from induction of anaesthesia to the end of cardiopulmonary bypass, and eight to receive an equivalent volume of matched placebo (0.9% sodium chloride). Commencement of cardiopulmonary bypass decreased renal medullary tissue oxygenation in the placebo group (mean (95%CI) 5.96 (4.24-7.23) to 1.56 (0.84-2.09) kPa, p = 0.001), with similar hypoxic levels observed in the dexmedetomidine group (6.33 (5.33-7.07) to 1.51 (0.33-2.39) kPa, p = 0.002). While no differences in kidney function (i.e. reduced creatinine clearance) were evident, a greater incidence of histological renal tubular injury was observed in sheep receiving dexmedetomidine (7/8 sheep) compared with placebo (2/8 sheep), p = 0.041. Graded on a semi-quantitative scale (0-3), median (IQR [range]) severity of histological renal tubular injury was higher in the dexmedetomidine group compared with placebo (1.5 (1-2 [0-3]) vs. 0 (0-0.3 [0-1]) respectively, p = 0.013). There was no difference in cerebral tissue microglial activation (neuroinflammation) between the groups. Dexmedetomidine did not reduce renal medullary hypoxia or cerebral neuroinflammation in sheep undergoing cardiopulmonary bypass.


Asunto(s)
Dexmedetomidina , Animales , Encéfalo , Puente Cardiopulmonar , Dexmedetomidina/uso terapéutico , Riñón , Microcirculación , Enfermedades Neuroinflamatorias , Ovinos
15.
BMC Public Health ; 23(1): 424, 2023 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-36869343

RESUMEN

BACKGROUND: A relationship between smoking and interpersonal influences has been well established within the literature. There have been cultural shifts in denormalisation and a reduction in tobacco smoking in many countries. Hence there is a need to understand social influences on adolescents' smoking across smoking normalisation contexts. METHODS: The search was conducted in July 2019 and updated in March 2022 within 11 databases and secondary sources. Search terms included schools, adolescents, smoking, peers, social norms and qualitative research. Screening was conducted by two researchers independently and in duplicate. Study quality was assessed using the eight-item Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-centre) tool for the appraisal of qualitative studies. Results were synthesised using a meta-narrative lens for meta-ethnography and compared across smoking normalisation contexts. RESULTS: Forty one studies were included and five themes were developed, mapping onto the socio ecological model. The social processes by which adolescents take up smoking differed according to a mixture of school type, peer group structure and the smoking culture within the school, as well as the wider cultural context. Data available from smoking denormalised contexts, described changes in social interactions around smoking to cope with its stigmatisation. This was manifested through i) direct peer influence, whereby subtle techniques were employed, ii) group belonging whereby smoking was less likely to be seen as a key determinant of group membership and smoking was less commonly reported to be used as a social tool, and iii) popularity and identity construction, whereby smoking was perceived more negatively in a denormalised context, compared with a normalised context. CONCLUSIONS: This meta-ethnography is the first study to demonstrate, drawing on international data, that peer processes in adolescent smoking may undergo changes as smoking norms within society change. Future research should focus on understanding differences across socioeconomic contexts, to inform the adaptation of interventions.


Asunto(s)
Amigos , Control del Tabaco , Adolescente , Humanos , Fumar , Fumar Tabaco , Investigación Cualitativa , Antropología Cultural
16.
Neurobiol Dis ; 172: 105815, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35820645

RESUMEN

Dopaminergic neurons in the substantia nigra pars compacta (SNc) differentially degenerate in Parkinson's Disease, with the ventral region degenerating more severely than the dorsal region. Compared with the dorsal neurons, the ventral neurons in the SNc have distinct dendritic morphology, electrophysiological characteristics, and circuit connections with the basal ganglia. These characteristics shape information processing in the ventral SNc and structure the balance of inhibition and disinhibition in the striatonigral circuitry. In this paper, I review foundational studies and recent work comparing the circuitry of the ventral and dorsal SNc neurons and discuss how loss of the ventral neurons early in Parkinson's Disease could affect the overall balance of inhibition and disinhibition of dopamine signals.


Asunto(s)
Neuronas Dopaminérgicas , Enfermedad de Parkinson , Ganglios Basales/fisiología , Neuronas Dopaminérgicas/patología , Humanos , Enfermedad de Parkinson/patología , Porción Compacta de la Sustancia Negra , Sustancia Negra/patología
17.
Thorax ; 77(5): 508-510, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34996848

RESUMEN

A subset of patients with hypersensitivity pneumonitis (HP) develop lung fibrosis that is clinically similar to idiopathic pulmonary fibrosis (IPF). To address the aetiological determinants of fibrotic HP, we investigated whether the common IPF genetic risk variants were also relevant in study subjects with fibrotic HP. Our findings indicate that common genetic variants in TERC, DSP, MUC5B and IVD were significantly associated with fibrotic HP. These findings provide support for a shared etiology and pathogenesis between fibrotic HP and IPF.


Asunto(s)
Alveolitis Alérgica Extrínseca , Fibrosis Pulmonar Idiopática , Alveolitis Alérgica Extrínseca/genética , Fibrosis , Humanos , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/patología , Pulmón/patología , Factores de Riesgo
18.
Thorax ; 77(1): 86-90, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34183448

RESUMEN

The prognostic value of peripheral blood mononuclear cell (PBMC) expression profiles, when used in patients with chronic hypersensitivity pneumonitis (CHP), as an adjunct to traditional clinical assessment is unknown. RNA-seq analysis on PBMC from 37 patients with CHP at initial presentation determined that (1) 74 differentially expressed transcripts at a 10% false discovery rate distinguished those with (n=10) and without (n=27) disease progression, defined as absolute FVC and/or diffusing capacity of the lungs for carbon monoxide (DLCO) decline of ≥10% and increased fibrosis on chest CT images within 24 months, and (2) classification models based on gene expression and clinical factors strongly outperform models based solely on clinical factors (baseline FVC%, DLCO% and chest CT fibrosis).


Asunto(s)
Alveolitis Alérgica Extrínseca , Leucocitos Mononucleares , Alveolitis Alérgica Extrínseca/diagnóstico por imagen , Alveolitis Alérgica Extrínseca/genética , Humanos , Pulmón , Pronóstico , Transcriptoma
19.
Proc Natl Acad Sci U S A ; 116(26): 12666-12671, 2019 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-31160443

RESUMEN

Nanomaterials have tremendous potential to increase electrochromic smart window efficiency, speed, and durability. However, nanoparticles vary in size, shape, and surface defects, and it is unknown how nanoparticle heterogeneity contributes to particle-dependent electrochromic properties. Here, we use single-nanoparticle-level electro-optical imaging to measure structure-function relationships in electrochromic tungsten oxide nanorods. Single nanorods exhibit a particle-dependent waiting time for tinting (from 100 ms to 10 s) due to Li-ion insertion at optically inactive surface sites. Longer nanorods tint darker than shorter nanorods and exhibit a Li-ion gradient that increases from the nanorod ends to the middle. The particle-dependent ion-insertion kinetics contribute to variable tinting rates and magnitudes across large-area smart windows. Next, we quantified how particle-particle interactions impact tinting dynamics and reversibility as the nanorod building blocks are assembled into a thin film. Interestingly, single particles tint 4 times faster and cycle 20 times more reversibly than thin films made of the same particles. These findings allow us to propose a nanostructured electrode architecture that optimizes optical modulation rates and reversibility across large-area smart windows.

20.
Phys Rev Lett ; 126(8): 082301, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33709760

RESUMEN

Quasielastic ^{12}C(e,e^{'}p) scattering was measured at spacelike 4-momentum transfer squared Q^{2}=8, 9.4, 11.4, and 14.2 (GeV/c)^{2}, the highest ever achieved to date. Nuclear transparency for this reaction was extracted by comparing the measured yield to that expected from a plane-wave impulse approximation calculation without any final state interactions. The measured transparency was consistent with no Q^{2} dependence, up to proton momenta of 8.5 GeV/c, ruling out the quantum chromodynamics effect of color transparency at the measured Q^{2} scales in exclusive (e,e^{'}p) reactions. These results impose strict constraints on models of color transparency for protons.

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