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An increase in temperature along with a decrease in summer precipitation in Central Europe will result in an increased frequency of drought events and gradually lead to a change in species composition in forest ecosystems. In the present study, young oaks (Quercus robur L. and Quercus petraea (Matt.) Liebl.) were transplanted into large mesocosms and exposed for 3 years to experimental warming and a drought treatment with yearly increasing intensities. Carbon and oxygen isotopic (δ13C and δ18O) patterns were analysed in leaf tissue and tree-ring cellulose and linked to leaf physiological measures and tree-ring growth. Warming had no effect on the isotopic patterns in leaves and tree rings, while drought increased δ18O and δ13C. Under severe drought, an unexpected isotopic pattern, with a decrease in δ18O, was observed in tree rings but not in leaves. This decrease in δ18O could not be explained by concurrent physiological analyses and is not supported by current physiological knowledge. Analysis of intra-annual tree-ring growth revealed a drought-induced growth cessation that interfered with the record of isotopic signals imprinted on recently formed leaf carbohydrates. This missing record indicates isotopic uncoupling of leaves and tree rings, which may have serious implications for the interpretation of tree-ring isotopes, particularly from trees that experienced growth-limiting stresses. [ABSTRACT FROM AUTHOR]

Global climate change is expected to increase annual temperatures and decrease summer precipitation in Central Europe. Little is known of how forests respond to the interaction of these climate factors and if their responses depend on soil conditions. In a 3-year lysimeter experiment, we investigated the growth response of young mixed oak stands, on either acidic or calcareous soil, to soil water regime, air-warming and drought treatments corresponding to an intermediate climate change scenario. The air-warming and drought treatments were applied separately as well as in combination. The air-warming treatment had no effect on soil water availability, evapotranspiration or stand biomass. Decreased evapotranspiration from the drought-exposed stands led to significantly higher air and soil temperatures, which were attributed to impaired transpirational cooling. Water limitation significantly reduced the stand foliage, shoot and root biomass as droughts were severe, as shown in low leaf water potentials. Additional air warming did not enhance the drought effects on evapotranspiration and biomass, although more negative leaf water potentials were observed. After re-watering, evapotranspiration increased within a few days to pre-drought levels. Stands not subjected to the drought treatment produced significantly less biomass on the calcareous soil than on the acidic soil, probably due to P or Mn limitation. There was no difference in biomass and water regime between the two soils under drought conditions, indicating that nutrient availability was governed by water availability under these conditions. The results demonstrate that young oak stands can cope with severe drought and therefore can be considered for future forestry. [ABSTRACT FROM AUTHOR]

Three Central European oak species, with four provenances each, were experimentally tested in 16 large model ecosystem chambers for their response to passive air warming (AW, ambient +1-2 °C), drought (D, −43 to −60% irrigation) and their combination (AWD) for 3 years on two forest soil types of pH 4 or 7. Throughout the entire experiment, the influence of the different ambient and experimental climates on the oak trees was strong. The morphological traits of the Quercus species were affected in opposing ways in AW and D treatments, with a neutral effect in the AWD treatment. Biochemical parameters and LMA showed low relative plasticity compared to the morphological and growth parameters. The high plasticity in physiologically important parameters of the three species, such as number of intercalary veins or leaf size, indicated good drought acclimation properties. The soil type influenced leaf chlorophyll concentration, C/N and area more than drought, whereas foliage mass was more dependent on drought than on soil type. Through comparison of visible symptom development with the water deficits, a drought tolerance threshold of −1.3 MPa was determined. Although Q. pubescens had xeromorphic leaf characteristics (small leaf size, lower leaf water content, high LMA, pilosity, more chlorophyll, higher C/N) and less response to the treatments than Q. petraea and Q. robur, it suffered more leaf drought injury and shedding of leaves than Q. petraea. However, if foliage mass were used as the criterion for sustainable performance under a future climate, Q. robur would be the most appropriate species. [ABSTRACT FROM AUTHOR]

Being tolerant to heat and drought, oaks are promising candidates for future forestry in view of climate change in Central Europe. Air warming is expected to increase, and drought decrease soil N availability and thus N supply to trees. Here, we conducted a model ecosystem experiment, in which mixed stands of young oaks ( Quercus robur, Q. petraea and Q. pubescens) were grown on two different soils and subjected to four climate treatments during three growing seasons: air warming by 1-2 °C, drought periods (average precipitation reduction of 43-60%), a combination of these two treatments, and a control. In contrast to our hypotheses, neither air warming nor drought significantly affected N availability, whereas total amounts, vertical distribution and availability of soil N showed substantial differences between the two soils. While air warming had no effect on tree growth and N accumulation, the drought treatment reduced tree growth and increased, or tended to increase, N accumulation in the reduced biomass, indicating that growth was not limited by N. Furthermore, 15 N-labelling revealed that this accumulation was associated with an increased uptake of nitrate. On the basis of our results, climate change effects on N dynamics are expected to be less important in oak stands than reduced soil water availability. [ABSTRACT FROM AUTHOR]

Oaks are commonly considered as drought- and heat-tolerant trees that might benefit from a warmer and drier climate. Their tolerance to drought has been frequently studied in the past, whereas studies dealing with elevated temperature or its combination with drought are very limited in number. In this study we investigated seasonal photosynthetic patterns in three European oak species ( Quercus robur, Q. petraea, Q. pubescens) exposed in lysimeter-based open-top chambers (OTC) to elevated daytime temperature, drought and their combination. Stomatal and non-stomatal traits of photosynthesis were followed over an entire growing season and related to changes in daytime temperature, soil moisture and pre-dawn leaf water potential (ΨPD). Elevated daytime temperature enhanced net photosynthesis (PN) in a season-dependent manner, with higher mid-summer rates than in controls exposed to ambient temperature. Drought imposed in early and mid-summer reduced the soil moisture content and caused a gradual decline in ΨPD, stomatal conductance (gS) and PN. Drought effects on ΨPD and PN were exacerbated when drought was combined with elevated daytime temperature. In general, PN tended to be more affected by low soil moisture content or low ΨPD in Q. robur than in Q. petraea and Q. pubescens. Non-stomatal limitations may have contributed to the drought-induced decline of PN in Q. robur, as indicated by a down-regulation of PSII photochemistry (FV/FM) and decreased chlorophyll content. Taken together, our findings show that European oaks may benefit from elevated temperature, but detrimental effects can be expected when elevated temperature occurs simultaneously with drought. [ABSTRACT FROM AUTHOR]

Climate-tolerant tree species and/or provenances have to be selected to ensure the high productivity of managed forests in Central Europe under the prognosticated climate changes. For this purpose, we studied the responses of saplings from three oak species ( i.e. Quercus robur, Q. petraea and Q. pubescens) and provenances of different climatic origin ( i.e. low or high rainfall, low or high temperature habitats) with regard to leaf nitrogen (N) composition as a measure of N nutrition. Saplings were grown in model ecosystems on either calcareous or acidic soil and subjected to one of four treatments (control, drought, air warming or a combination of drought and air warming). Across species, oak N metabolism responded to the influence of drought and/or air warming with an increase in leaf amino acid N concentration at the expense of structural N. Moreover, provenances or species from drier habitats were more tolerant to the climate conditions applied, as indicated by an increase in amino acid N (comparing species) or soluble protein N (comparing provenances within a species). Furthermore, amino acid N concentrations of oak leaves were significantly higher on calcareous compared to acidic soil. From these results, it can be concluded that seeds from provenances or species originating from drier habitats and - if available - from calcareous soil types may provide a superior seed source for future forest establishment. [ABSTRACT FROM AUTHOR]

The drought- and thermo-tolerant Quercus pubescens, a tree species growing on both acidic and calcareous soils in the sub-Mediterranean region, was exposed to soil drought (−60% to −80% soil water content) and air warming (+1.2 °C daytime temperature), singly and in combination. The experiment was conducted on two natural forest soils with similar texture but different pH (acidic and calcareous soils). The physiological (photosynthesis) and biochemical (antioxidant system) responses of Q. pubescens were investigated. On acidic soil, Q. pubescens had a higher reactive oxygen species (ROS) content than on calcareous soil, confirming that this species is better adapted to the latter soil type. A down-regulation of ascorbate-glutathione cycle enzymes suggests that ROS were used as signalling molecules. Air warming stimulated stomatal opening, while soil drought induced stomatal closure in the late afternoon and reduced Rubisco carboxylation efficiency. Photosynthetic performance in the combined treatment was higher than under single drought stress and similar to control and air warming. Q. pubescens biochemical responses depended on soil pH. On acidic soil, Q. pubescens trees exposed to air warming used ROS as signalling molecules. On calcareous soil, these trees were able to balance both soil drought and air warming stress, avoiding ROS toxic effects by increasing antioxidant enzyme activitiy and maintaining a high enzymatic antioxidant defence. When combined, drought and air warming induced either more severe (higher oxidative pressure and impairment of the light-harvesting complex) or different responses (decline of the thermal energy dissipation capacity) relative to the single stressors. Overall, however, Q. pubescens preserved the functionality of the photosynthetic apparatus and controlled the antioxidant system response, thus confirming its drought and thermo-tolerance and therefore its potential to adapt to the ongoing climate change. [ABSTRACT FROM AUTHOR]

Several severe drought events have been reported in southern Europe during recent decades. Drought has been found to increase the mortality of the southernmost populations of Scots pine forests in Mediterranean countries and in dry inner-alpine valleys. Therefore the ongoing global climate change is likely to endanger Scots pine in future decades. Carbon starvation might be the main cause of the increasing mortality rate due to less carbon uptake and consequently to high susceptibility to biotic attacks. Forest management, in particular, thinning and shrub removal could decrease the intensity of drought stress by decreasing competition for water resources and thus increasing carbon uptake. The ongoing climate change and adaptive forest management will both play an important role for the sustainability of this specie across southern regions of Europe. [ABSTRACT FROM AUTHOR]

Patients with brain death have by definition irreversible and complete loss of brainstem reflexes. Before a definite diagnosis of brain death can be confirmed, all potential confounders must be thoroughly excluded. Baclofen intoxication is a rare cause of brain death mimic characterised by transient deep coma and absence of brainstem reflexes and might be mistaken with brain death. We report the case of a female patient in her 70s who ingested baclofen with suicidal intent and was admitted with a deep coma and loss of all brainstem reflexes and a spontaneous burst-suppression pattern in the electroencephalography which resolved over 10 hours. After a state mimicking brain death for 6 hours, the patient experienced complete recovery. Severe baclofen intoxication can mimic brain death clinically and is associated with temporary pathological electroencephalographic findings. Awareness of this toxidrome is crucial, as appropriate management can lead to full recovery., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To compare the SUHB mobility scale (i.e., stable(S), unstable gait(U), needing help to walk(H), or bedridden(B)) and the Emergency Severity Index (ESI) associations with admission and mortality outcomes., Design: Post-hoc analysis of a prospective observational study including all consenting presenting to the ED over a period of 3 weeks. Odd ratios and AUCs were calculated to assess predictive performance of SUHB and compared with ESI., Results: Out of 2422 patients, 65% presented with a stable gait, 45% with an ESI level 3. With increasing mobility impairment on the SUHB scale, the probability for admission and mortality increased. SUHB had a higher AUC than ESI for 1-year mortality., Conclusion: SUHB was a better predictor than ESI of long-term mortality. The scale, which is rapid, requires little additional training, and no extra costs, could be used as a useful supplement to the triage process.

Background/objectives: To determine the prevalence and severity of traumatic intracranial hemorrhage (tICH) in a large cohort of older adults presenting with low-energy falls and the association with anticoagulation or antiplatelet medication., Design: Bicentric retrospective cohort analysis., Setting: Two level 1 trauma centers in Switzerland and Germany., Participants: Consecutive sample of older adults (aged ≥65 y) presenting to the emergency department (ED) over a 1-year period with low-energy falls who received cranial computed tomography (cCT) within 48 hours of ED presentation., Measurements: The prevalence and severity of tICHs was assessed and the outcomes (in-hospital mortality, admission to intensive care unit [ICU], or neurosurgical intervention) were specified. We used multivariate regression models to measure the association between anticoagulation/antiplatelet therapy and the risk for tICH after adjustment for known predictors., Results: The overall prevalence for tICH detected by cCT was 176 of 2567 (6.9%). Neurosurgical intervention was performed in 15 of 176 (8.5%) patients with tICH, 28 of 176 (15.9%) patients were admitted to the ICU, and 14 of 176 (8.0%) died in the hospital. CT-detected skull fracture and signs of injury above the clavicles were the strongest predictors for the presence of tICH (odds ratio [OR] = 4.28; 95% confidence interval [CI] = 2.79-6.51; OR = 1.88; 95% CI = 1.3-2.73, respectively). Among 2567 included patients, 1424 (55%) were on anticoagulation/antiplatelet therapy. Multivariate regression models showed no differences for the risk of tICH (OR = 1.05; 95% CI = .76-1.47; P = .76) or association with the head-specific Injury Severity Scale (incident rate ratio = 1.08; 95% CI = .97-1.19; P = .15) with or without anticoagulation/antiplatelet therapy., Conclusion: Medication with anticoagulants or antiplatelet agents was not associated with higher prevalence and severity of tICH in older patients with low-energy falls undergoing cCT examination. In addition to cCT-detected skull fractures, visible injuries above the clavicles were the strongest clinical predictors for tICH. Our findings merit prospective validation. J Am Geriatr Soc 68:977-982, 2020., (© 2020 The American Geriatrics Society.)

Our objective was to compare informal physicians' disease severity ratings (PDSR) at presentation with the well-established Emergency Severity Index (ESI) in order to test for non-inferiority of the discriminatory ability regarding hospitalization, intensive care, and mortality. We made a prospective observational study with consecutive enrollment. At presentation, the PDSR and subsequently Emergency Severity Index (ESI) levels were recorded. The primary outcome was the non-inferiority of the discriminatory ability (PDSR versus ESI) regarding hospitalization, intensive care, and mortality. The secondary outcomes were the reliability, the predictive validity, and the safety of PDSR. We included 6859 patients. The median age was 51 years (interquartile range (IQR) = 33 to 72 years); 51.4% were males. There were 159 non-survivors (2.4%) at the 30 day follow-up. The PDSR's discriminatory ability was non-inferior to the ESI's discriminatory ability. The safety assessment showed mortality of <0.5% in low-acuity patients in both tools. The predictive validity increased by 3.5 to 7 times if adding high-acuity PDSR to ESI in all categories with mortality of >1%. Our data showed the non-inferiority of PDSR compared with ESI regarding discriminatory ability, a moderate reliability, and an acceptable safety of both tools.

The predictive power of certain symptoms, such as dyspnoea, is well known. However, research is limited to the investigation of single chief complaints. This is in contrast to patients in the emergency department (ED) presenting usually more than one symptom. We aimed to identify the most common combinations of symptoms and to report their related outcomes: hospitalisation, admission to intensive care units, and mortality. This is a secondary analysis of a consecutive sample of all patients presenting to the ED of the University Hospital Basel over a total time course of 6 weeks. The presence of 35 predefined symptoms was systematically assessed upon presentation. A total of 3960 emergency patients (median age 51, 51.7% male) were included. Over 130 combinations of two, 80 combinations of three, and 10 combinations of four symptoms occurred 42 times or more during a total inclusion period of 42 days. Two combinations of two symptoms were predictive for in-hospital mortality: weakness and fatigue (Odds ratio (OR) = 2.45), and weakness and headache (OR = 3.01). Combinations of symptoms were frequent. Nonspecific complaints (NSCs), such as weakness and fatigue, are among the most frequently reported combinations of symptoms, and are associated with adverse outcomes. Systematically assessing symptoms may add valuable information for prognosis and may therefore influence triage, clinical work-up, and disposition.

Dermanyssus gallinae, the poultry red mite (PRM), is a blood-feeding ectoparasite capable of causing pathology in birds, amongst other animals. It is an increasingly important pathogen in egg layers and is responsible for substantial economic losses to the poultry industry worldwide. Even though PRM poses a serious problem, very little is known about the basic biology of the mite. Here we review the current body of literature describing red mite biology and discuss how this has been, or could be, used to develop methods to control PRM infestations. We focus primarily on the PRM digestive system, salivary glands, nervous system and exoskeleton and also explore areas of PRM biology which have to date received little or no study but have the potential to offer new control targets.

Tree water relations and their dependence on microclimate and soil moisture were studied over several months in young oaks (Quercus robur L.) subjected in large lysimeter-based open top chambers to environments with a controlled soil water supply. Automated single point dendrometers and the recently developed leaf patch clamp pressure (LPCP) probe were used for monitoring water-related stem radius variations (ΔW) and turgor-dependent leaf patch pressures (Pp). Both parameters showed distinct diurnal patterns with sharp negative and positive peaking of ΔW and Pp, respectively, after solar noon and recovery to initial levels in the evening. During the day, varying solar radiation was responsible for short time fluctuations of Pp in the range of minutes to hours reflecting feedback regulation of leaf turgor by sunlight driven stomatal movements. At longer timescales, i.e. days to months, atmospheric vapour pressure deficit (VPD) and soil water content (SWC) were the main determinants of ΔW and Pp. Daily minimum and maximum values of ΔW and Pp decreased and increased, respectively, with increasing VPD or decreasing SWC and recovery of ΔW and Pp in the evening was impeded by low SWC. In well-watered oaks, daily positive peaking of Pp preceded daily negative peaking of ΔW; these time lags gradually increased with increasing soil drought, suggesting hydraulic uncoupling of stem and leaves.

Background: More than 900 hemoglobin (Hb) variants are currently known. Common techniques used in Hb analysis are electrophoretic and chromatographic assays. In our laboratory, we routinely apply chromatographic methods. To ascertain whether Hb variants are missed with our procedures, we additionally analyzed all samples with mass spectrometry (MS)., Methods: Database evaluation was performed using all entries made in the Hb variant database HbVar, and possible Hb variants were calculated based on DNA variations. During a 5-year period, we analyzed 2105 lysates with cation-exchange HPLC (PolyCAT A column) and reversed-phase HPLC and additionally with electrospray ionization or MALDI-TOF MS. Globin chains were identified by their molecular masses., Results: Database evaluation revealed that 43.2% of all possible Hbalpha- and beta-chain variants were found to date (considering only single-point mutations). Currently, 68.2% of the possible charge difference variants and only 28.7% of the neutral variants are found. Among 2105 Hb samples we identified 4 samples with Hb variants that were detected only with the MS method; 2 were new Hb variants (Hb Zurich-Hottingen and Hb Zurich-Langstrasse). With cation-exchange HPLC, 1 sample was found to be a beta-thalassemia and was identified by MS to be a beta-variant (Hb Malay). More common variants, such as Hb C, Hb D, and Hb E, and thalassemias could not be detected with the MS method., Conclusions: Application of MS improves the sensitivity of Hb analysis. The combination of MS with electrophoretic and chromatographic methods is optimal for the detection of Hb variants.

The transition to the care of the college student-athlete carries with it a number of adjustments. In private practice it is customary to make medical decisions and initiate therapies from the confines of the examination room. The doctor-patient relationship is the principal focus. Although this relationship remains paramount in college athletics, the world of concerned and affected parties dramatically expands. It is in this context that the authors explore the concept of access in the role of a team physician. To use what is becoming an over used cliché, what makes one a valued team physician is being "the right person, in the right place at the right time."

Single proteins, when analyzed with 2-D-PAGE, often show multiple spots due to PTMs. In gels of human body fluids, the spot patterns facilitate the assignment and identification of the proteins. We analyzed serums from patients with congenital disorders of glycosylation (CDG) in which glycoproteins are strongly impacted and exhibit highly distinguishable spot patterns compared to healthy controls. We detected a typical protein pattern for alpha1-acid glycoprotein (AGP) and transferrin (Trf) that are markers for CDG. AGP contains five glycosylation sites which results in a complex microheterogeneity of the glycoprotein. On the other hand, in Trf, a glycoprotein with only two glycosylation sites, mainly biantennary complex-type-N-linked glycans are bound. We used 2-D-PAGE, MALDI-TOF-MS, and ESI-MS for the analysis of these glycoproteins and their corresponding glycans. In AGP, the heterogenic glycosylation of the different glycosylation sites is responsible for the complex spot pattern. In contrast to AGP, the protein spots of Trf cannot be explained by glycosylation. We found strong evidence that oxidation of cysteine is responsible for the spot pattern. This study contradicts the commonly accepted assumption that the multiple protein spots of Trf observed in 2-D-PAGE are due, as in AGP, to the glycosylation of the protein.

Background: Hemoglobin (Hb) heterogeneity arises mainly from posttranslational modifications of the globin chains, and cation-exchange chromatography reveals falsely increased concentrations of some minor Hbs in the presence of abnormal Hbs. Here we describe a method for identification of the globin chains and their posttranslational modifications contained in the Hb fractions., Methods: We used cation-exchange HPLC (PolyCAT A column) for separation of Hb fractions and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for analysis of the separated globin chains. Globin chains were identified by their molecular masses. Posttranslational modifications of globin chains were identified by digestion of the proteins with endoproteinase V8 before MALDI-TOF MS of the resulting peptides., Results: Analysis of the HbA2 fractions of patients with HbS revealed 4 different globin chains. We found, in addition to the expected alpha- and delta-chains, the carbamylated alpha- and the betaS-chains. Additionally, we analyzed HbH, Hb Barts, HbA 1b, pre-HbA 1c, HbA 1c, HbF1, HbF, HbA 1d3a, HbA 1d3b, HbA2, and HbC1 fractions from control and pathologic blood samples. We identified several posttranslational modifications of the globin chains, such as pyruvatization, glycation, acetylation, carbamylation, and acetaldehyde adduct formation., Conclusions: The native and posttranslationally modified globin chains in minor and major Hbs are unambiguously identified by MALDI-TOF MS. A minor Hb containing the carbamylated alpha- and the betaS-chain elutes at the same time as normal HbA2 (alpha2delta2) and thus leads to falsely increased HbA2 values in patients with HbS when blood is analyzed with PolyCAT A chromatography.

In this study, we present a versatile new procedure for the analysis of transferrin and its isoforms isolated from human body fluids such as serum, plasma, and cerebrospinal fluid. This method is based on a three-step procedure: (i) isolation of transferrins using anion-exchange chromatography with UV detection; (ii) concentration of the transferrin fraction; (iii) detection of the transferrins with liquid chromatography-electrospray mass spectrometry. Pre-analytical sample procedures can be omitted and no immunoaffinity columns or transferrin-specific immunoassays were used. Anticoagulants such as heparin, EDTA, citrate, and oxalate do not interfere with our analysis. According to their respective molecular masses, up to ten different isoforms of transferrin could be identified in a serum sample from a patient with a congenital disorder of glycosylation type Ia (CDG-Ia). The method was successfully applied to different pathological samples from patients with CDG-Ia, CDG-Ib, CDG-Ic, CDG-Ie, CDG-If, and CDG-IIa. Additionally, samples from alcohol consumers that were found with turbidimetric immunoassay to contain increased levels of carbohydrate-deficient transferrin were analyzed.