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1.
Nat Commun ; 15(1): 4289, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38782899

RESUMEN

Extreme weather and coronavirus-type pandemics are both leading global health concerns. Until now, no study has quantified the compound health consequences of the co-occurrence of them. We estimate the mortality attributable to extreme heat and cold events, which dominate the UK health burden from weather hazards, in England and Wales in the period 2020-2022, during which the COVID-19 pandemic peaked in terms of mortality. We show that temperature-related mortality exceeded COVID-19 mortality by 8% in South West England. Combined, extreme temperatures and COVID-19 led to 19 (95% confidence interval: 16-22 in North West England) to 24 (95% confidence interval: 20-29 in Wales) excess deaths per 100,000 population during heatwaves, and 80 (95% confidence interval: 75-86 in Yorkshire and the Humber) to 127 (95% confidence interval: 123-132 in East of England) excess deaths per 100,000 population during cold snaps. These numbers are at least ~2 times higher than the previous decade. Society must increase preparedness for compound health crises such as extreme weather coinciding with pandemics.


Asunto(s)
COVID-19 , Pandemias , SARS-CoV-2 , COVID-19/mortalidad , COVID-19/epidemiología , Humanos , Inglaterra/epidemiología , Gales/epidemiología , Mortalidad/tendencias , Clima Extremo , Calor Extremo/efectos adversos
2.
Nat Commun ; 15(1): 4530, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816393

RESUMEN

The 2021 Pacific Northwest heatwave was so extreme as to challenge conventional statistical and climate-model-based approaches to extreme weather attribution. However, state-of-the-art operational weather prediction systems are demonstrably able to simulate the detailed physics of the heatwave. Here, we leverage these systems to show that human influence on the climate made this event at least 8 [2-50] times more likely. At the current rate of global warming, the likelihood of such an event is doubling every 20 [10-50] years. Given the multi-decade lower-bound return-time implied by the length of the historical record, this rate of change in likelihood is highly relevant for decision makers. Further, forecast-based attribution can synthesise the conditional event-specific storyline and unconditional event-class probabilistic approaches to attribution. If developed as a routine service in forecasting centres, it could provide reliable estimates of human influence on extreme weather risk, which is critical to supporting effective adaptation planning.

3.
Int J Climatol ; 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37874919

RESUMEN

Combined heat and humidity is frequently described as the main driver of human heat-related mortality, more so than dry-bulb temperature alone. While based on physiological thinking, this assumption has not been robustly supported by epidemiological evidence. By performing the first systematic comparison of eight heat stress metrics (i.e., temperature combined with humidity and other climate variables) with warm-season mortality, in 604 locations over 39 countries, we find that the optimal metric for modelling mortality varies from country to country. Temperature metrics with no or little humidity modification associates best with mortality in ~40% of the studied countries. Apparent temperature (combined temperature, humidity and wind speed) dominates in another 40% of countries. There is no obvious climate grouping in these results. We recommend, where possible, that researchers use the optimal metric for each country. However, dry-bulb temperature performs similarly to humidity-based heat stress metrics in estimating heat-related mortality in present-day climate.

4.
Environ Res Lett ; 17(2): 024017-24017, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35341022

RESUMEN

Heatwaves are a serious threat to human life. Public health agencies that are responsible for delivering heat-health action plans need to assess and reduce the mortality impacts of heat. Statistical models developed in epidemiology have previously been used to attribute past observed deaths to high temperatures and project future heat-related deaths. Here, we investigate the novel use of summer temperature-mortality associations established by these models for monitoring heat-related deaths in regions in England in near real time. For four summers in the period 2011-2020, we find that coupling these associations with observed daily mean temperatures results in England-wide heatwave mortality estimates that are consistent with the excess deaths estimated by UK Health Security Agency. However, our results for 2013, 2018 and 2020 highlight that the lagged effects of heat and characteristics of individual summers contribute to disagreement between the two methods. We suggest that our method can be used for heatwave mortality monitoring in England because it has the advantages of including lagged effects and controlling for other risk factors. It could also be employed by health agencies elsewhere for reliably estimating the health burden of heat in near real time and near-term forecasts.

6.
Ecohealth ; 13(1): 200-12, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26915507

RESUMEN

As the Ebola outbreak in West Africa wanes, it is time for the international scientific community to reflect on how to improve the detection of and coordinated response to future epidemics. Our interdisciplinary team identified key lessons learned from the Ebola outbreak that can be clustered into three areas: environmental conditions related to early warning systems, host characteristics related to public health, and agent issues that can be addressed through the laboratory sciences. In particular, we need to increase zoonotic surveillance activities, implement more effective ecological health interventions, expand prediction modeling, support medical and public health systems in order to improve local and international responses to epidemics, improve risk communication, better understand the role of social media in outbreak awareness and response, produce better diagnostic tools, create better therapeutic medications, and design better vaccines. This list highlights research priorities and policy actions the global community can take now to be better prepared for future emerging infectious disease outbreaks that threaten global public health and security.


Asunto(s)
Control de Enfermedades Transmisibles/organización & administración , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , Brotes de Enfermedades/prevención & control , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Salud Pública , Salud Global , Humanos
7.
Physiol Behav ; 32(3): 489-502, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6463130

RESUMEN

The development of the first standardized "scratch 'n sniff" olfactory test is described. Over 1600 subjects participated in five experiments. In Experiment 1, 50 microencapsulated odorants were rated as to their intensity, pleasantness, irritation, coolness, and familiarity, and two procedures for releasing them were compared. In Experiment 2, the results of the first experiment and other data were used in the development of the test, which was administered to a large number of subjects. Using multiple regression analysis, scores on this test were shown to be significantly related to the subjects' gender, ethnic background, and smoking behavior. Average test scores decreased as a function of age, with the greatest decline occurring between the sixth and tenth decades of life. These age-related changes were not correlated with scores on the Wechsler Memory Scale. Women performed better than men within all age categories. In Experiment 3, the test was shown to differentiate between subjects with known olfactory disorders (e.g., Kallmann's syndrome; Korsakoff's syndrome) and normal controls, and to reliably detect persons instructed to feign total anosmia. In Experiment 4, the test-retest reliability was established (6-month interval; r = 0.918, p less than 0.001), and in Experiment 5 the test was shown to correlate thresholds with odor detection (r = -0.794, p less than 0.001). This self-administratered test now makes it possible to rapidly and accurately assess general olfactory function in the laboratory, clinic, or through the mail without complex equipment or space-consuming stores of chemicals.


Asunto(s)
Olfato/fisiología , Adolescente , Adulto , Factores de Edad , Trastorno Amnésico Alcohólico/fisiopatología , Umbral Diferencial , Femenino , Humanos , Masculino , Simulación de Enfermedad/fisiopatología , Esclerosis Múltiple/fisiopatología , Odorantes , Trastornos del Olfato/fisiopatología , Estimulación Física , Fisiología/métodos , Grupos Raciales , Análisis de Regresión , Factores Sexuales , Fumar
8.
Laryngoscope ; 94(2 Pt 1): 176-8, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6694486

RESUMEN

Despite the fact that clinical otolaryngologists are often presented with complaints of olfactory dysfunction, they have limited means to diagnose these problems. A major reason has been the lack of a clinically-useful and reliable quantitative test of olfactory function. Recent work at our Clinical Research Center has resulted in the development of such a test. This test--the University of Pennsylvania Smell Identification Test (UPSIT)--can be self-administered and uses microencapsulated odorants which are released by scratching standardized odor-impregnated test booklets. As indicated in this paper, studies have demonstrated that the UPSIT can identify most malingerers and is sensitive to age, gender, smoking habits, and a wide variety of olfactory disorders. A description of this new test, along with some of its applications, is presented.


Asunto(s)
Trastornos del Olfato/diagnóstico , Olfato , Humanos
9.
J Antibiot (Tokyo) ; 31(5): 398-404, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-670082

RESUMEN

LL-BM123beta, gamma1 and gamma2 are three new antibiotics produced by fermentation of an unidentified species of Nocardia. These strongly basic, water soluble compounds were isolated from the culture filtrate by CM-Sephadex ion-exchange and carbon chromatography. All three antibiotics are active against both gram-positive and gram-negative bacteria. A mixture of LL-BM123 gamma1 and gamma2 is more active than the beta component but generally less active than gentamicin.


Asunto(s)
Antibacterianos/análisis , Espermidina/análogos & derivados , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Fenómenos Químicos , Química Física , Femenino , Ratones , Nocardia/análisis , Espermidina/análisis , Espermidina/farmacología
10.
Plant Physiol ; 99(1): 153-60, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-16668843

RESUMEN

The activation of spinach (Spinacia oleracea) chloroplast coupling factor 1 (CF(1)) by thioredoxin (ThR) was characterized using membrane-bound and soluble CF(1). Light generates an electrochemical proton gradient across the thylakoid membrane, which increases the accessibility of the disulfide bond on the gamma-subunit of CF(1) to reduced ThR. The proton gradient substantially accelerates the activation of CF(1) compared with thylakoids incubated in the dark with similar concentrations of dithiothreitol and ThR. The interaction of soluble CF(1) with ThR was studied using fluorescent probes. CF(1) in solution, with and without its associated epsilon-subunit, was labeled at Cys-322 of the gamma-subunit with fluoresceinyl maleimide. ThR from Escherichia coli was labeled with eosin isothiocyanate. Labeled ThR and CF(1) showed normal activities. Fluorescence energy transfer between donor fluoresceinyl maleimide and acceptor eosin isothiocyanate, manifested by a quenching of the donor fluorescence, was detected, suggesting that ThR and CF(1) form an intermolecular complex. When the epsilon-subunit was absent, quenching of donor fluorescence was approximately doubled, indicating that labeled ThR could approach more closely to the gamma-subunit of CF(1). The distance between the fluorescent probes on CF(1) and ThR was calculated to be approximately 65 A when epsilon-subunit was present and 52 A when epsilon was absent. These values are consistent with other distance measurements and energy transfer values reported previously for fluorescent probes on CF(1). Whereas the extent of quenching increased by removal of the epsilon-subunit, the apparent dissociation constant was unchanged. The quenching effect was reversed when the epsilon-subunit was added back to the titration mixture. Similarly, the addition of unlabeled ThR decreased donor quenching.

11.
Plant Physiol ; 91(1): 427-32, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16667037

RESUMEN

The effect of ozone (O(3)) on ribulose bisphosphate carboxylase/oxygenase (Rubisco) activity and quantity and net photosynthesis in greenhouse-grown Solanum tuberosum L. cv ;Norland' foliage was studied in relation to oxidant-induced premature senescence. Plants, 26 days old, were exposed to 0.06 to 0.08 microliters per liter O(3) from 1000 to 1600 hours for 4 days in a controlled environment chamber. On day 5, plants were exposed to a 6-hour simulated inversion in which O(3) peaked at 0.12 microliters per liter. Net photosynthesis declined in response to O(3) but recovered to near control levels 3 days after the exposure ended. Rubisco activity and quantity in control potato foliage increased and then decreased during the 12-day interval of the study. In some experiments foliage studied was physiologically mature and Rubisco activity had peaked when O(3) exposure commenced. In those cases, O(3) accelerated the decline in Rubisco activity. When less mature foliage was treated with O(3), the leaves never achieved the maximal level of Rubisco activity observed in control foliage and also exhibited more rapid decline in initial and total activity. Percent activation of Rubisco (initial/total activity) was not affected significantly by treatment. Quantity of Rubisco decreased in concert with activity. The decrease in activities is most likely due to a decrease in available protein rather than a decrease in the percentage of Rubisco activated in vivo. The reduction in the quantity of Rubisco, an important foliar storage protein, could contribute to premature senescence associated with toxicity of this air pollutant.

12.
Biochem J ; 141(2): 495-501, 1974 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4455218

RESUMEN

The specificity of the S(1)' subsite of the proteolytic enzyme papain was investigated by studying the effect of l-alpha-amino acid amides on the enzyme-catalysed hydrolysis of N-benzyloxycarbonylglycine p-nitrophenyl ester and by determining the kinetic parameters for the enzyme-catalysed hydrolysis of some N-benzyloxycarbonylglycyl-l-amino acid amides. These studies showed that the S(1)' subsite has a predilection for hydrophobic residues, in particular l-leucine and l-tryptophan. The specificity for these residues is manifest in both the binding and acylation steps. N-Benzyloxycarbonylglycine amide is not hydrolysed under comparable conditions, indicating that the amide group adjacent to and on the C-terminal side of the peptide bond about to be cleaved makes an important contribution to the rate of the papain-catalysed hydrolysis of peptides.


Asunto(s)
Papaína , Amidas , Compuestos de Bencilo , Sitios de Unión , Glicina , Concentración de Iones de Hidrógeno , Cinética , Leucina , Nitrofenoles , Unión Proteica , Triptófano
13.
Plant Physiol ; 109(4): 1379-88, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8539297

RESUMEN

The gene encoding the epsilon subunit (atpE) of the chloroplast ATP synthase of Spinacia oleracea has been overexpressed in Escherichia coli. The recombinant protein can be solubilized in 8 M urea and directly diluted into buffer containing ethanol and glycerol to obtain epsilon that is as biologically active as epsilon purified from chloroplast-coupling factor 1 (CF1). Recombinant epsilon folded in this manner inhibits the ATPase activity of soluble and membrane-bound CF1 deficient in epsilon and restores proton impermeability to thylakoid membranes reconstituted with CF1 deficient in epsilon. Site-directed mutagenesis was used to generate truncations and single amino acid substitutions in the primary structure of epsilon. In the five mutants tested, alterations that weaken ATPase inhibition by recombinant epsilon affect its ability to restore proton impermeability to a similar extent, with one exception. Substitution of histidine-37 with arginine appears to uncouple ATPase inhibition and the restoration of proton impermeability. As in the case of E. coli, it appears that N-terminal truncations of the epsilon subunit have more profound effects than C-terminal deletions on the function of epsilon. Recombinant epsilon with six amino acids deleted from the C terminus, which is the only region of significant mismatch between the epsilon of spinach and the epsilon of Pisum sativum, inhibits ATPase activity with a reduced potency similar to that of purified pea epsilon. Four of the six amino acids are serine or threonine. These hydroxylated amino acids may be important in epsilon-CF1 interactions.


Asunto(s)
Cloroplastos/enzimología , Genes de Plantas , ATPasas de Translocación de Protón/química , ATPasas de Translocación de Protón/metabolismo , Spinacia oleracea/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Chlamydomonas/enzimología , Clonación Molecular , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Escherichia coli/enzimología , Membranas Intracelulares/enzimología , Cinética , Sustancias Macromoleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Plantas/enzimología , Reacción en Cadena de la Polimerasa , ATPasas de Translocación de Protón/aislamiento & purificación , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia , Homología de Secuencia de Aminoácido
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