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1.
BMC Biol ; 22(1): 135, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38867210

RESUMEN

BACKGROUND: Evolution of novelty is a central theme in evolutionary biology, yet studying the origins of traits with an apparently discontinuous origin remains a major challenge. Venom systems are a well-suited model for the study of this phenomenon because they capture several aspects of novelty across multiple levels of biological complexity. However, while there is some knowledge on the evolution of individual toxins, not much is known about the evolution of venom systems as a whole. One way of shedding light on the evolution of new traits is to investigate less specialised serial homologues, i.e. repeated traits in an organism that share a developmental origin. This approach can be particularly informative in animals with repetitive body segments, such as centipedes. RESULTS: Here, we investigate morphological and biochemical aspects of the defensive telopodal glandular organs borne on the posterior legs of venomous stone centipedes (Lithobiomorpha), using a multimethod approach, including behavioural observations, comparative morphology, proteomics, comparative transcriptomics and molecular phylogenetics. We show that the anterior venom system and posterior telopodal defence system are functionally convergent serial homologues, where one (telopodal defence) represents a model for the putative early evolutionary state of the other (venom). Venom glands and telopodal glandular organs appear to have evolved from the same type of epidermal gland (four-cell recto-canal type) and while the telopodal defensive secretion shares a great degree of compositional overlap with centipede venoms in general, these similarities arose predominantly through convergent recruitment of distantly related toxin-like components. Both systems are composed of elements predisposed to functional innovation across levels of biological complexity that range from proteins to glands, demonstrating clear parallels between molecular and morphological traits in the properties that facilitate the evolution of novelty. CONCLUSIONS: The evolution of the lithobiomorph telopodal defence system provides indirect empirical support for the plausibility of the hypothesised evolutionary origin of the centipede venom system, which occurred through functional innovation and gradual specialisation of existing epidermal glands. Our results thus exemplify how continuous transformation and functional innovation can drive the apparent discontinuous emergence of novelties on higher levels of biological complexity.


Asunto(s)
Artrópodos , Animales , Artrópodos/fisiología , Venenos de Artrópodos/química , Evolución Biológica , Transcriptoma , Filogenia
2.
J Antimicrob Chemother ; 79(3): 564-566, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38198576

RESUMEN

BACKGROUND: Little is known about the distribution of posaconazole in brain tissue and CSF. We therefore analysed trough concentrations of posaconazole in paediatric leukaemia patients in non-inflamed CSF. PATIENTS AND METHODS: The study included paediatric patients <18 years of age with acute leukaemia in remission who underwent repeat therapeutic lumbar punctures as part of their anti-leukaemia treatment. CSF and blood were obtained 20-24 h after dosing, and posaconazole was measured by LC-MS/MS. RESULTS: Six patients (median age: 10 years; range, 6-14) with acute lymphatic (three) or acute myeloid (three) leukaemia were included who received posaconazole gastroresistant tablets at weight-banded doses (five) or the oral solution (one). In contrast to 14 control samples, posaconazole was detectable in all 11 samples of treated patients. CSF concentrations ranged from 8.3 to 42 ng/mL with a median CSF concentration of 13.6 ng/mL. Concurrent serum concentrations were between 965 and 5177 ng/mL with a median of 1716 ng/mL. CONCLUSIONS: Trough concentrations of posaconazole in the CSF after systemic administration were low but detectable in all subjects. Concurrent serum concentrations were in the target range for prophylaxis and treatment in 100% and 90%, respectively.


Asunto(s)
Antifúngicos , Leucemia Mieloide Aguda , Triazoles , Humanos , Niño , Cromatografía Liquida , Administración Oral , Espectrometría de Masas en Tándem , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/tratamiento farmacológico , Estudios Retrospectivos
3.
Eur J Haematol ; 112(6): 879-888, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38297484

RESUMEN

OBJECTIVES: Midostaurin is an oral multitargeted tyrosine kinase inhibitor for the treatment of acute myeloid leukemia (AML). Therapeutic drug monitoring of midostaurin may support its safe use when suspecting toxicity or combined with strong CYP3A4 inhibitors. METHODS: A stable isotope dilution liquid chromatography-tandem mass spectrometry method was developed and validated for the determination and quantification of midostaurin in human plasma and serum. Midostaurin serum concentrations were analyzed in 12 patients with FMS-like tyrosine kinase 3 (FLT3)-mutated AML during induction chemotherapy with cytarabine, daunorubicin, and midostaurin. Posaconazole was used as prophylaxis of invasive fungal infections. RESULTS: Linear quantification of midostaurin was demonstrated across a concentration range of 0.01-8.00 mg/L. Inter- and intraday imprecisions of the proposed method were well within ±10%. Venous blood samples were taken in nine and three patients in the first and second cycle of induction chemotherapy. Median (range) midostaurin serum concentration was 7.9 mg/L (1.5-26.1 mg/L) as determined in 37 independent serum specimens. CONCLUSION: In a real-life cohort of AML patients, interindividual variability in midostaurin serum concentrations was high, highlighting issues concerning optimal drug dosing in AML patients. A personalized dosage approach may maximize the safety of midostaurin. Prospective studies and standardization of analytical methods to support such an approach are needed.


Asunto(s)
Leucemia Mieloide Aguda , Estaurosporina , Estaurosporina/análogos & derivados , Espectrometría de Masas en Tándem , Humanos , Estaurosporina/uso terapéutico , Estaurosporina/administración & dosificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , Cromatografía Liquida/métodos , Adulto , Monitoreo de Drogas/métodos , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/sangre , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/sangre , Inhibidores de Proteínas Quinasas/farmacocinética , Reproducibilidad de los Resultados , Estudios de Cohortes
4.
Inorg Chem ; 63(16): 7286-7292, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38592208

RESUMEN

The perfluorinated silylphosphinidene, F3SiP, in the triplet ground state is generated by the reaction of laser-ablated silicon atoms with PF3 in solid neon and argon matrices. The reactions proceed with the initial formation of a silicon trifluorophosphine complex, F3PSi, in the triplet ground state, and a more stable inserted phosphasilene, FPSiF2, in the singlet ground state upon deposition. The trifluorosilylphosphinidene was formed through F-migration reactions of FPSiF2 and F3PSi following a two-state mechanism under irradiation with visible light (λ = 470 nm) and full arc light (λ > 220 nm), respectively. High-level quantum-chemical methods support the identification of F3PSi, FPSiF2, and F3SiP by matrix-isolation IR spectroscopy.

5.
Pharm Stat ; 23(4): 495-510, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38326967

RESUMEN

We present the motivation, experience, and learnings from a data challenge conducted at a large pharmaceutical corporation on the topic of subgroup identification. The data challenge aimed at exploring approaches to subgroup identification for future clinical trials. To mimic a realistic setting, participants had access to 4 Phase III clinical trials to derive a subgroup and predict its treatment effect on a future study not accessible to challenge participants. A total of 30 teams registered for the challenge with around 100 participants, primarily from Biostatistics organization. We outline the motivation for running the challenge, the challenge rules, and logistics. Finally, we present the results of the challenge, the participant feedback as well as the learnings. We also present our view on the implications of the results on exploratory analyses related to treatment effect heterogeneity.


Asunto(s)
Ensayos Clínicos Fase III como Asunto , Motivación , Humanos , Ensayos Clínicos Fase III como Asunto/métodos , Industria Farmacéutica , Proyectos de Investigación , Resultado del Tratamiento , Bioestadística/métodos , Interpretación Estadística de Datos
6.
Angew Chem Int Ed Engl ; 63(7): e202317770, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38131450

RESUMEN

Radical trifluoromethoxylation is an attractive approach to prepare compounds featuring the important OCF3 group, however most existing methods have focused on aromatic substrates. Here, we report novel methodologies with alkenyl substrates employing bis(trifluoromethyl)peroxide (BTMP) as a practical and comparatively atom economical trifluoromethoxylating reagent. With silyl enol ether substrates, switching reaction solvent allows for the synthesis of either α-(trifluoromethoxy)ketone products or unprecedented alkenyl-OCF3 species. Furthermore, allyl silanes have been employed as substrates for the first time, affording allyl(trifluoromethyl)ether products in good yields. In each case, the methods operate at room temperature without large excesses of the alkene substrate while, in contrast to previous radical trifluoromethoxylation reactions, no catalyst, light or other activators are required.

7.
J Chem Ecol ; 49(7-8): 384-396, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37231188

RESUMEN

Hypogean petrels return to the same nest burrow to breed on remote islands during the summer months. Their nocturnal behavior at the colony, strong musky odor and olfactory anatomy suggest an important role of olfaction in homing behavior and nest recognition. Behavioral experiments showed that olfactory cues are sufficient to allow nest identification, suggesting a stabile chemical signature emanating from burrows and facilitating nest recognition. However, the chemical nature and sources of this odor remain unknown. To better understand the nest odor composition, we analyzed volatile organic compounds (VOCs) of nests of blue petrels (Halobaena caerulea) derived from three different odor sources: nest air, nest material and feather samples. We also compared, during two successive years, VOCs from burrows with an incubating breeder on the nest, and burrows used during the breeding season by blue petrels but shortly temporally unoccupied by breeders. We found that the nest air odor was mainly formed by the owners' odor, which provided an individual chemical label for nests that appeared stabile over the breeding season. These findings, together with the previous homing behavioral studies showing an essential role of the sense of smell in blue petrels, strongly suggest that the scent emanating from burrows of blue petrels provides the information that facilitates nest recognition and homing.


Asunto(s)
Odorantes , Olfato , Animales , Feromonas , Aves , Plumas
8.
BMC Musculoskelet Disord ; 24(1): 221, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36959595

RESUMEN

INTRODUCTION: Hip and knee osteoarthritis are associated with functional limitations, pain and restrictions in quality of life and the ability to work. Furthermore, with growing prevalence, osteoarthritis is increasingly causing (in)direct costs. Guidelines recommend exercise therapy and education as primary treatment strategies. Available options for treatment based on physical activity promotion and lifestyle change are often insufficiently provided and used. In addition, the quality of current exercise programmes often does not meet the changing care needs of older people with comorbidities and exercise adherence is a challenge beyond personal physiotherapy. The main objective of this study is to investigate the short- and long-term (cost-)effectiveness of the SmArt-E programme in people with hip and/or knee osteoarthritis in terms of pain and physical functioning compared to usual care. METHODS: This study is designed as a multicentre randomized controlled trial with a target sample size of 330 patients. The intervention is based on the e-Exercise intervention from the Netherlands, consists of a training and education programme and is conducted as a blended care intervention over 12 months. We use an app to support independent training and the development of self-management skills. The primary and secondary hypotheses are that participants in the SmArt-E intervention will have less pain (numerical rating scale) and better physical functioning (Hip Disability and Osteoarthritis Outcome Score, Knee Injury and Osteoarthritis Outcome Score) compared to participants in the usual care group after 12 and 3 months. Other secondary outcomes are based on domains of the Osteoarthritis Research Society International (OARSI). The study will be accompanied by a process evaluation. DISCUSSION: After a positive evaluation, SmArt-E can be offered in usual care, flexibly addressing different care situations. The desired sustainability and the support of the participants' behavioural change are initiated via the app through audio-visual contact with their physiotherapists. Furthermore, the app supports the repetition and consolidation of learned training and educational content. For people with osteoarthritis, the new form of care with proven effectiveness can lead to a reduction in underuse and misuse of care as well as contribute to a reduction in (in)direct costs. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00028477. Registered on August 10, 2022.


Asunto(s)
Osteoartritis de la Cadera , Osteoartritis de la Rodilla , Anciano , Humanos , Terapia por Ejercicio/métodos , Estudios Multicéntricos como Asunto , Osteoartritis de la Rodilla/complicaciones , Dolor , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Teléfono Inteligente , Resultado del Tratamiento , Ensayos Clínicos Pragmáticos como Asunto
9.
Inorg Chem ; 61(3): 1672-1684, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34985262

RESUMEN

Several new diphenylamino- and diphenylphosphanyldialkylalanes are reported, which were characterized in solution and in the solid state, assisted by in-depth bonding analysis within the DFT framework. In the case of bulky alkyl substituents on the aluminum atom, the species are stable in their monomeric form and were structurally characterized by single crystal X-ray diffraction, expanding the relatively small field of monomeric pnictogenylalanes. In the case of oligomeric diphenylpnictogenyldimethylalanes, their reactivity toward different σ-donor ligands was studied, and several examples of monomeric adducts could be structurally characterized, including the first cyclic(alkyl)(amino)carbene complexes. The reactivity of these CAAC complexes, their oligomeric precursors, and an unstabilized monomeric aminoalane toward CO2 was probed, leading to different insertion products that could be characterized. Additionally, the mechanism was elucidated by DFT calculations.

10.
Environ Res ; 207: 112216, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-34656630

RESUMEN

Patterns and practices of agricultural expansion threaten the persistence of global biodiversity. Wildlife species surviving large-scale land use changes can be exposed to a suite of contaminants that may deleteriously impact their health. There is a paucity of data concerning the ecotoxicological impacts associated with the global palm oil (Elaeis guineensis) industry. We sampled wild Malay civets (Viverra tangalunga) across a patchwork landscape degraded by oil palm agriculture in Sabah, Malaysian Borneo. Using a non-lethal methodology, we quantified the levels of 13 essential and non-essential metals within the hair of this adaptable small carnivore. We robustly assessed the biological and environmental drivers of intrapopulation variation in measured levels. Metal concentrations were associated with civet age, weight, proximity to a tributary, and access to oxbow lakes. In a targeted case study, the hair metal profiles of 16 GPS-collared male civets with differing space use patterns were contrasted. Civets that entered oil palm plantations expressed elevated aluminium, cadmium, and lead, and lower mercury hair concentrations compared to civets that remained exclusively within the forest. Finally, we paired hair metal concentrations with 34 blood-based health markers to evaluate the possible sub-lethal physiological effects associated with varied hair metal levels. Our multi-facetted approach establishes these adaptable carnivores as indicator species within an extensively altered ecosystem, and provides critical and timely evidence for future studies.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Agricultura , Biodiversidad , Bosques
11.
Klin Padiatr ; 234(5): 293-300, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34979579

RESUMEN

BACKGROUND: Persistent air leak (PAL) is a severe complication of secondary spontaneous pneumothorax (SSP). Surgical interventions are usually successful when medical treatment fails, but can be associated with significant complications and loss of potentially recoverable lung parenchyma. METHODS: Retrospective analysis of efficacy and safety of interventional bronchus occlusions (IBO) using Amplatzer devices (ADs) in children with PAL secondary to SSP. RESULTS: Six patients (four males, 4-15 years of age) underwent IBO using ADs as treatment for PAL. Necrotizing pneumonia (NP) was the most common cause (n=4) of PAL. Three patients were previously healthy and three suffered from chronic lung disease. All patients required at least two chest tubes prior to the intervention for a duration of 15-43 days and all required oxygen or higher level of ventilatory support. In three cases, previous surgical interventions had been performed without success. All children improved after endobronchial intervention and we observed no associated complications. All chest tubes were removed within 5-25 days post IBO. In patients with PAL related to NP (n=4), occluders were removed bronchoscopically without re-occurrence of pneumothorax after a mean of 70 days (IQR: 46.5-94). CONCLUSION: IBO using ADs is a safe and valuable treatment option in children with PAL independent of disease severity and underlying cause. A major advantage of this procedure is its less invasiveness compared to surgery and the parenchyma- preserving approach.


Asunto(s)
Neumotórax , Complicaciones Posoperatorias , Bronquios/cirugía , Tubos Torácicos/efectos adversos , Niño , Humanos , Masculino , Oxígeno , Neumotórax/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/terapia , Estudios Retrospectivos
12.
Postharvest Biol Technol ; 191: 111976, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36061628

RESUMEN

Garlic (Allium sativum L.) has long been grown for its culinary and health-promoting qualities. The seasonal nature of garlic cropping requires that bulbs be stored for many months after harvest to ensure a year-round supply. During this time, quality is known to deteriorate, and efforts have been made to improve the longevity of stored bulbs. Cold temperatures within the stores prolong shelf life, but fine temperature control is needed to avoid freezing damage or cold induced stress. Here, quality traits (alliinase activity, firmness, and water content) are measured in response to a 96 h - 5 °C cold stress, to simulate the effect of non-isothermic temperature control in a - 1.5 °C warehouse. Volatile organic compounds (VOCs) are measured by thermal desorption gas chromatography time of flight mass spectrometry to identify markers of non-isothermic storage in garlic. 129 compounds were putatively identified and four (L-lactic acid, 2,6-dimethylhetpadecane, 4-methyldodecane, and methylcyclopentane) showed high predictive accuracy for cold stress. VOCs were also sampled directly from a cold storage facility and the whole profile discriminated between sampling time points. Five VOCS were highly predictive for storage time in the warehouse but were different to VOCs previously shown to discriminate between storage times in a laboratory setting. This indicates the need for realistic warehouse experiments to test quality markers.

13.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35458995

RESUMEN

Beach handball is a young discipline that is characterized by numerous high-intensity actions. By following up on previous work, the objective was to perform in-depth analyses evaluating external load (e.g., distance traveled, velocity, changes in direction, etc.) in beach handball players. In cross-sectional analyses, data of 69 players belonging to the German national or prospective team were analyzed during official tournaments using a local positioning system (10 Hz) and inertial measurement units (100 Hz). Statistical analyses comprised the comparison of the first and second set and the effects of age and sex (female adolescents vs. male adolescents vs. male adults) and playing position (goalkeepers, defenders, wings, specialists, and pivots) on external load measures. We found evidence for reduced external workload during the second set of the matches (p = 0.005, ηp2 = 0.09), as indicated by a significantly lower player load per minute and number of changes in direction. Age/sex (p < 0.001, ηp2 = 0.22) and playing position (p < 0.001, ηp2 = 0.29) also had significant effects on external load. The present data comprehensively describe and analyze important external load measures in a sample of high-performing beach handball players, providing valuable information to practitioners and coaches aiming at improving athletic performance in this new sport.


Asunto(s)
Rendimiento Atlético , Artículos Domésticos , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Estudios Prospectivos
14.
J Sci Food Agric ; 102(11): 4500-4513, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-35122271

RESUMEN

BACKGROUND: There is increasing consumer demand for olive oil to be traceable. However, genotype, environmental factors, and stage of maturity, all affect the flavor and composition of both the olives and olive oil. Few studies have included all three variables. Key metabolites include lipids, phenolics, and a wide range of volatile organic compounds (VOCs), which provide the olives and oil with their characteristic flavor. Here we aim to identify markers that are able to discriminate between cultivars, that can identify growth location, and can discriminate stages of fruit maturity. 'Nocellara messinese' and 'Carolea' olive fruits were grown at three locations differing in altitude in Calabria, Italy, and harvested at three stages of maturity. Oil was analyzed from the two most mature stages. RESULTS: Nine and 20 characters discriminated all fruit and oil samples respectively, and relative abundance of two fatty acids distinguished all oils. Whole VOC profiles discriminated among the least mature olives, and oil VOC profiles discriminated location and cultivar at both stages. Three VOCs putatively identified as hexanal, methyl acetate, and 3-hexen-1-ol differentiated all samples of oils from the most mature fruit stage. CONCLUSION: The results confirm that interactions of location, cultivar and fruit maturity stage are critical for the overall pattern of aroma compounds, and identify potential markers of commercial relevance. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Olea , Compuestos Orgánicos Volátiles , Frutas/química , Olea/química , Aceite de Oliva/química , Fenoles/análisis , Compuestos Orgánicos Volátiles/química
15.
Angew Chem Int Ed Engl ; 61(43): e202209684, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-35924885

RESUMEN

The preparation and structural characterization of [NEt3 Me]2 [SCl6 ] is described, which is the first example of a [SCl6 ]2- dianion and of a halosulfate anion of the type [Sx Xy ]z- in general. This dianion belongs to the group of 14-valence electron AB6 E systems and forms an octahedral structure in the solid-state. Interestingly, co-crystallization with CH2 Cl2 affords [NEt3 Me]2 [SCl6 ]⋅4 CH2 Cl2 containing [SCl6 ]2- dianions with C4v symmetry. As suggested by quantum-chemical calculations, the distortion of the structure is not caused by a stereochemically active lone pair but by enhanced hydrogen bonding interactions with CH2 Cl2 . At elevated temperatures, [NEt3 Me]2 [SCl6 ] decomposes to various sulfur chlorine compounds as shown by Raman spectroscopy. Cooling back to room temperature results in the selective formation of [NEt3 Me]2 [SCl6 ] which is comparable to the well-studied SCl4 .

16.
Chemistry ; 27(21): 6500-6510, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33411379

RESUMEN

Several 1,1'-diphosphanyl-substituted metallocenes of magnesium (magnesocenes) were synthesized, structurally characterized, and their reactivity and coordination chemistry were investigated. Transmetalation of these magnesocenes gives access to group 14 metallocenes (tetrelocenes), as well as to group 15 stibonocenes. These s- and p-block metallocenes represent a novel class of bis(phosphanyl) ligands, exhibiting Lewis-amphiphilic character. Their coordination chemistry towards different transition-metal and main-group fragments was investigated and different complexes are presented.

17.
Front Zool ; 18(1): 17, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33879192

RESUMEN

BACKGROUND: The jointed appendage is a key novelty in arthropod evolution and arthropod legs are known to vary enormously in relation to function. Among centipedes, the ultimate legs always are distinctly different from locomotory legs, and different centipede taxa evolved different structural and functional modifications. In Geophilomorpha (soil centipedes), ultimate legs do not participate in locomotion and were interpret to serve a sensory function. They can be sexually dimorphic and in some species, male ultimate legs notably appear "hairy". It can be assumed that the high abundance of sensilla indicates a pronounced sensory function. This study seeks for assessing the sensory diversity, however, documents the surprising and unique case of an extensive glandular epithelium in the ultimate legs of three phylogenetically distant species. RESULTS: The tightly aggregated epidermal glands with stalked ducts - mistakenly thought to be sensilla - were scrutinized using a multimodal microscopic approach comprising histology as well as scanning and transmission electron microscopy in Haplophilus subterraneus. Hence, this is the first detailed account on centipede ultimate legs demonstrating an evolutionary transformation into a "secretory leg". Additionally, we investigated sensory structures as well as anatomical features using microCT analysis. Contrary to its nomination as a tarsus, tarsus 1 possesses intrinsic musculature, which is an indication that this podomere might be a derivate of the tibia. DISCUSSION: The presence and identity of ultimate leg associated epidermal glands with stalked ducts is a new discovery for myriapods. A pronounced secretory as well as moderate sensory function in Haplophilus subterraneus can be concluded. The set of characters will improve future taxonomic studies, to test the hypotheses whether the presence of these specialized glands is a common feature in Geophilomorpha, and that tarsus 1 may be a derivate of the tibia. As the number of epidermal glands with stalked ducts is sexually dimorphic, their function might be connected to reproduction or a sex-specific defensive role. Our results, in particular the unexpected discovery of 'glandular hairs', may account for a striking example for how deceptive morphological descriptions of epidermal organs may be, if based on non-invasive techniques alone.

18.
Front Zool ; 18(1): 57, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34736489

RESUMEN

BACKGROUND: Centipedes are terrestrial, predatory arthropods with specialized sensory organs. However, many aspects of their sensory biology are still unknown. This also concerns hygroreception, which is especially important for centipedes, as their epicuticle is thin and they lose water rapidly at low humidity. Thus, the detection of humid places is vital but to date no definite hygroreceptor was found in centipedes. House centipedes (Scutigeromorpha) possess a peculiar opening at the base of their antenna, termed 'scape organ', that houses up to 15 cone-shaped sensilla in a cavity. Lacking wall and tip-pores, these socket-less sensilla may be hypothesized to function as hygroreceptors similar to those found in hexapods. RESULTS: The cone-shaped sensilla in the scape organ as well as nearby peg-shaped sensilla are composed of three biciliated receptor cells and three sheath cells. A tip-pore is present but plugged by a highly electron-dense secretion, which also overlays the entire inner surface of the cavity. Several solitary recto-canal epidermal glands produce the secretion. Receptor cell type 1 (two cells in cone-shaped sensilla, one cell in peg-shaped sensilla) possesses two long dendritic outer segments that project to the terminal pore. Receptor cell type 2 (one cell in both sensilla) possesses two shorter dendritic outer segments connected to the first (proximal) sheath cell that establishes a scolopale-like structure, documented for the first time in detail in a myriapod sensillum. CONCLUSIONS: The nearly identical configuration of receptor cells 1 with their long dendritic outer segments in both sensilla is similar to hexapod hygroreceptors. In Scutigera coleoptrata, however, the mechanism of stimulus transduction is different. Water vapor may lead to swelling and subsequent elongation of the plug pin that enters the terminal pore, thus causing stimulation of the elongated dendritic outer segments. The interconnection of receptor cell 2 with short outer dendritic segments to a scolopale-like structure potentially suits both sensilla for vibration or strain detection. Thus, both sensilla located at the antennal base of scutigeromorph centipedes fulfill a dual function.

19.
Br J Clin Pharmacol ; 87(11): 4293-4303, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33818823

RESUMEN

AIMS: To describe the population pharmacokinetics (PK) and probability of target attainment (PTA) of continuous infusion (CI) of meropenem in septic patients receiving renal replacement therapy (RRT). METHODS: Fifteen patients without RRT, 13 patients receiving sustained low-efficiency dialysis and 12 patients receiving continuous veno-venous haemodialysis were included. Population PK analysis with Monte Carlo simulations for different dosing regimens was performed. For minimum inhibitory concentration 2 mg/L was chosen. The target was set as 50% time ≥4× minimum inhibitory concentration. RESULTS: The PK of meropenem was best described by a 1-compartment model with linear elimination. Serum creatinine, residual diuresis and time on RRT, with no difference between sustained low-efficiency dialysis and continuous veno-venous haemodialysis, were found to be significant covariates affecting clearance, explaining >20% of the clearance between subject variability. PTA analysis showed that in patients with RRT, 2 g/24 h, meropenem CI achieved a PTA of 95%. In patients without RRT, the target was achieved with 3 g/24 h CI or prolonged infusion of 1 g meropenem over 8 hours but not with bolus application of 1 g meropenem for 8 hours. Only 2 patients (both without RRT) had meropenem concentrations below the target level. However, approximately half of the patients with RRT receiving CI 3 g/24 h meropenem had toxic concentrations. CONCLUSION: We found relevant PK variability for meropenem CI in septic patients with or without RRT, leading to a substantial risk for overdosing in patients with RRT. This finding highlights the strong demand for personalized dosing in critically ill patients.


Asunto(s)
Terapia de Reemplazo Renal Continuo , Terapia de Reemplazo Renal Híbrido , Sepsis , Antibacterianos/uso terapéutico , Humanos , Meropenem , Probabilidad , Terapia de Reemplazo Renal , Sepsis/tratamiento farmacológico
20.
Transpl Int ; 34(3): 474-487, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33393142

RESUMEN

This study evaluated the impact of unilateral diaphragm elevation following bilateral lung transplantation on postoperative course. Patient data for all lung transplantations performed at our institution between 01/2010 and 12/2019 were reviewed. Presence of right or left diaphragm elevation was retrospectively evaluated using serial chest X-rays performed while patients were standing and breathing spontaneously. Right elevation was defined by a > 40 mm difference between right and left diaphragmatic height. Left elevation was present if the left diaphragm was at the same height or higher than the right diaphragm. In total, 1093/1213 (90%) lung transplant recipients were included. Of these, 255 (23%) patients exhibited radiologic evidence of diaphragm elevation (right, 55%; left 45%; permanent, 62%). Postoperative course did not differ between groups. Forced expiratory volume in 1 second, forced vital capacity and total lung capacity were lower at 1-year follow-up in patients with permanent than in patients with transient or absent diaphragmatic elevation (P = 0.038, P < 0.001, P = 0.002, respectively). Graft survival did not differ between these groups (P = 0.597). Radiologic evidence of diaphragm elevation was found in 23% of our lung transplant recipients. While lung function tests were worse in patients with permanent elevation, diaphragm elevation did not have any relevant impact on outcomes.


Asunto(s)
Diafragma , Trasplante de Pulmón , Diafragma/diagnóstico por imagen , Volumen Espiratorio Forzado , Humanos , Pulmón/diagnóstico por imagen , Trasplante de Pulmón/efectos adversos , Estudios Retrospectivos , Capacidad Vital
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