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1.
Chemphyschem ; : e202400453, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39382835

RESUMEN

The red/green cyanobacteriochrome (CBCR) slr1393g3 exhibits a quantum yield of only 8% for its forward photoconversion significantly lower than other species from the same CBCR subfamily. The cause for this reduced photoconversion is not yet clear, although in the related NpR6012g4 dark-state structural heterogeneity of a paramount Trp residue has been proposed to cause the formation of nonproductive subpopulation. However, there is no such information on the equivalent residue in slr1393g3, W496. Here we use solid-state NMR to explore all possible sidechain rotamers of this Trp residue and their local interactions at the atomic level. The indole nitrogen (Nε1) is used as an NMR probe, achieved by site-specific 15N-indole labeling of a quadruply Trp-deleted variant and trehalose vitrification technique. The data reveal a set of seven indole rotamers of W496 with four distinct environments for the Nε1-H group. Only a minority population of 20% is found to retain the π-stacking and hydrogen-bonding interactions with the chromophore in the dark state that has been assigned to account for complete forward photoconversion. Our results demonstrate the direct role of W496 in modulating the forward quantum yield of slr1393g3 via rearrangement of its sidechain rotameric conformations.

2.
BMC Emerg Med ; 24(1): 146, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39134954

RESUMEN

BACKGROUND: At the time of the COVID-19 pandemic, devastating incidents increased due to frequent oxygen administration to patients. The dangers associated with the use of oxygen, especially through local enrichments and formation of "oxygen clouds", have been well understood for years. Nevertheless, dramatic incidents continue to occur, since fire hazard increases exponentially with oxygen concentrations above 23%. Rescue helicopters are at a particular high risk, because of technical reasons such as oxygen use in a very small space, surrounded by kerosene lines, electronic relays and extremely hot surfaces. METHODS: In this study three different sized rescue helicopter models (Airbus H135, H145 and MD902) were examined. Oxygen enrichment in the cabin was measured with an oxymeter during a delivery rate of 15 l/min constant flow for 60 min. Furthermore, the clearance of the enriched atmosphere was tested in different situations and with different ventilation methods. To make the airflow visible, a fog machine was used to fill the helicopter cabin. RESULTS: Oxygen accumulation above 21% was detected in every helicopter. After 10-15 min, the critical 23% threshold was exceeded in all three aircrafts. The highest concentration was detected in the smallest machine (MD902) after 60 min with 27.4%. Moreover, oxygen clouds persisted in the rear and the bottom of the aircrafts, even when the front doors were opened. This was most pronounced in the largest aircraft, the H145 from Airbus Helicopters. Complete and rapid removal of elevated oxygen concentrations was achieved only by cross-ventilation within 1 min. CONCLUSIONS: Oxygen should be handled with particular care in rescue helicopters. Adapted checklists and precautions can help to prevent oxygen accumulation, and thus, fatal incidents. To our knowledge, this is the first study, which analyzed oxygen concentrations in different settings in rescue helicopters.


Asunto(s)
Ambulancias Aéreas , COVID-19 , Oxígeno , Humanos , COVID-19/epidemiología , Terapia por Inhalación de Oxígeno/métodos , SARS-CoV-2 , Ventilación
3.
J Immunol ; 207(1): 133-152, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34183371

RESUMEN

Autosomal recessive (AR) STAT1 deficiency is a severe inborn error of immunity disrupting cellular responses to type I, II, and III IFNs, and IL-27, and conferring a predisposition to both viral and mycobacterial infections. We report the genetic, immunological, and clinical features of an international cohort of 32 patients from 20 kindreds: 24 patients with complete deficiency, and 8 patients with partial deficiency. Twenty-four patients suffered from mycobacterial disease (bacillus Calmette-Guérin = 13, environmental mycobacteria = 10, or both in 1 patient). Fifty-four severe viral episodes occurred in sixteen patients, mainly caused by Herpesviridae viruses. Attenuated live measles, mumps, and rubella and/or varicella zoster virus vaccines triggered severe reactions in the five patients with complete deficiency who were vaccinated. Seven patients developed features of hemophagocytic syndrome. Twenty-one patients died, and death was almost twice as likely in patients with complete STAT1 deficiency than in those with partial STAT1 deficiency. All but one of the eight survivors with AR complete deficiency underwent hematopoietic stem cell transplantation. Overall survival after hematopoietic stem cell transplantation was 64%. A diagnosis of AR STAT1 deficiency should be considered in children with mycobacterial and/or viral infectious diseases. It is important to distinguish between complete and partial forms of AR STAT1 deficiency, as their clinical outcome and management differ significantly.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Linfohistiocitosis Hemofagocítica , Infecciones por Mycobacterium , Mycobacterium bovis , Humanos , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT1/metabolismo
4.
Photochem Photobiol Sci ; 21(9): 1627-1636, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35687310

RESUMEN

The ability of some knotless phytochromes to photoconvert without the PHY domain allows evaluation of the distinct effect of the PHY domain on their photodynamics. Here, we compare the ms dynamics of the single GAF domain (g1) and the GAF-PHY (g1g2) construct of the knotless phytochrome All2699 from cyanobacterium Nostoc punctiforme. While the spectral signatures and occurrence of the intermediates are mostly unchanged by the domain composition, the presence of the PHY domain slows down the early forward and reverse dynamics involving chromophore and protein binding pocket relaxation. We assign this effect to a more restricted binding pocket imprinted by the PHY domain. The photoproduct formation is also slowed down by the presence of the PHY domain but to a lesser extent than the early dynamics. This indicates a rate limiting step within the GAF and not the PHY domain. We further identify a pH dependence of the biphasic photoproduct formation hinting towards a pKa dependent tuning mechanism. Our findings add to the understanding of the role of the individual domains in the photocycle dynamics and provide a basis for engineering of phytochromes towards biotechnological applications.


Asunto(s)
Nostoc , Fitocromo , Proteínas Bacterianas/química , Nostoc/metabolismo , Fitocromo/química , Unión Proteica
5.
Photochem Photobiol Sci ; 21(4): 447-469, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35394641

RESUMEN

Cyanobacteriochromes (CBCRs) are phytochrome-related photosensory proteins that play an essential role in regulating phototaxis, chromatic acclimation, and cell aggregation in cyanobacteria. Here, we apply solid-state NMR spectroscopy to the red/green GAF2 domain of the CBCR AnPixJ assembled in vitro with a uniformly 13C- and 15N-labeled bilin chromophore, tracking changes in electronic structure, geometry, and structural heterogeneity of the chromophore as well as intimate contacts between the chromophore and protein residues in the photocycle. Our data confirm that the bilin ring D is strongly twisted with respect to the B-C plane in both dark and photoproduct states. We also identify a greater structural heterogeneity of the bilin chromophore in the photoproduct than in the dark state. In addition, the binding pocket is more hydrated in the photoproduct. Observation of interfacial 1H contacts of the photoproduct chromophore, together with quantum mechanics/molecular mechanics (QM/MM)-based structural models for this photoproduct, clearly suggests the presence of a biprotonated (cationic) imidazolium side-chain for a conserved histidine residue (322) at a distance of ~2.7 Å, generalizing the recent theoretical findings that explicitly link the structural heterogeneity of the dark-state chromophore to the protonation of this specific residue. Moreover, we examine pH effects on this in vitro assembled holoprotein, showing a substantially altered electronic structure and protonation of the photoproduct chromophore even with a small pH drop from 7.8 to 7.2. Our studies provide further information regarding the light- and pH-induced changes of the chromophore and the rearrangements of the hydrogen-bonding and electrostatic interaction network around it. Possible correlations between structural heterogeneity of the chromophore, protonation of the histidine residue nearby, and hydration of the pocket in both photostates are discussed.


Asunto(s)
Fotorreceptores Microbianos , Fitocromo , Proteínas Bacterianas/química , Pigmentos Biliares/química , Pigmentos Biliares/metabolismo , Histidina , Concentración de Iones de Hidrógeno , Luz , Fotorreceptores Microbianos/química , Fitocromo/metabolismo
6.
BMC Vet Res ; 17(1): 41, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33478485

RESUMEN

BACKGROUND: Despite clinical importance and frequent occurrence of sinus disease, little is known about the size of paranasal sinuses and their communication in ponies and small horses. To examine the shape and volume of the paranasal sinuses and evaluate the sinonasal communication, three-dimensional (3D) reconstructions of computed tomography (CT) datasets of 12 healthy adult Shetland ponies were performed and analysed. Linear measurements of head length and width were taken. Using semi-automatic segmentation, 3D-models of all sinus compartments were created. Volumetric measurement of the seven sinus compartments were conducted and statistical analysis was performed. Sinus volumes were compared between the left and right sinuses and the relation to age and head size was evaluated. RESULTS: Structure and shape of the paranasal sinus system in Shetland ponies was similar to that of large horses. All seven sinus compartments on each side of the head were identified (rostral maxillary sinus, ventral conchal sinus, caudal maxillary sinus, dorsal conchal sinus, middle conchal sinus, frontal sinus, sphenopalatine sinus). The existence of a bilateral cranial and a caudal system formed by a maxillary septum was visible in all 12 individuals. The volumetric sizes of the left and right sinuses did not differ significantly (p > 0.05). A positive correlation between the size of the paranasal sinuses and the head length was shown. A relation between sinus volumes and age could not be proved in adult ponies aged > six years. Communication between single sinus compartments was identified. Furthermore, communication with the nasal cavity over the nasomaxillary aperture (Apertura nasomaxillaris) and a common sinonasal channel (Canalis sinunasalis communis) as well as its splitting up into a rostral and a caudolateral channel could be seen. Examination of the sinonasal communication was challenging and only a descriptive evaluation was possible. CONCLUSIONS: Our findings concerning the size, shape and volumetric dimensions of Shetland pony CT images could help improve CT interpretation of abnormal clinical cases as well as aiding clinicians to develop and select appropriate instruments for medical inspection and treatments.


Asunto(s)
Caballos/anatomía & histología , Senos Paranasales/anatomía & histología , Factores de Edad , Animales , Femenino , Cabeza/anatomía & histología , Masculino , Cavidad Nasal/anatomía & histología , Senos Paranasales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/veterinaria
7.
Am J Med Genet A ; 164A(1): 251-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24352918

RESUMEN

Rubinstein-Taybi syndrome (RTS) and Cornelia de Lange syndrome (CdLS) are genetically heterogeneous multiple anomalies syndromes, each having a distinctive facial gestalt. Two genes (CREBBP and EP300) are known to cause RTS, and five (NIPBL, SMC1A, SMC3, RAD21, and HDAC8) have been associated with CdLS. A diagnosis of RTS or CdLS is molecularly confirmed in only 65% of clinically identified cases, suggesting that additional causative genes exist for both conditions. In addition, although EP300 and CREBBP encode homologous proteins and perform similar functions, only eight EP300 positive RTS patients have been reported, suggesting that patients with EP300 mutations might be escaping clinical recognition. We report on a child with multiple congenital abnormalities and intellectual disability whose facial features and complex phenotype resemble CdLS. However, no mutations in CdLS-related genes were identified. Rather, a novel EP300 mutation was found on whole exome sequencing. Possible links between EP300 and genes causing CdLS are evident in the literature. Both EP300 and HDAC8 are involved in the regulation of TP53 transcriptional activity. In addition, p300 and other chromatin associated proteins, including NIPBL, SMCA1, and SMC3, have been found at enhancer regions in different cell types. It is therefore possible that EP300 and CdLS-related genes are involved in additional shared pathways, producing overlapping phenotypes. As whole exome sequencing becomes more widely utilized, the diverse phenotypes associated with EP300 mutations should be better understood. In the meantime, testing for EP300 mutations in those with features of CdLS may be warranted.


Asunto(s)
Síndrome de Cornelia de Lange/diagnóstico , Síndrome de Cornelia de Lange/genética , Proteína p300 Asociada a E1A/genética , Exoma , Mutación del Sistema de Lectura , Fenotipo , Autopsia , Diagnóstico Diferencial , Facies , Resultado Fatal , Heterocigoto , Humanos , Lactante , Masculino , Síndrome de Rubinstein-Taybi/diagnóstico , Síndrome de Rubinstein-Taybi/genética
8.
Lab Med ; 55(1): 50-55, 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-37226975

RESUMEN

OBJECTIVE: The aim of this study was to assess the impact of hydroxocobalamin (OHCbl) infusion on arterial blood gas and oximetry values in patients with vasoplegic syndrome. METHODS: Blood samples collected from 95 patients receiving OHCbl infusion were assayed using the ABL90 FLEX Plus blood gas analyzer for the concentration of methemoglobin (MetHb), total hemoglobin (tHb), carboxyhemoglobin (COHb), arterial oxygen saturation (SaO2), arterial oxygen partial pressure (PaO2), and arterial carbon dioxide partial pressure (PaCO2). Interference of OHCbl on these variables was evaluated using the measured difference between the preinfusion and postinfusion samples. RESULTS: Blood MetHb (%) measured after the infusion of OHCbl (5g) were significantly higher than the baseline levels, with a median of 4.8 (IQR, 3.0-6.5) versus 1.0 (IQR, 1.0-1.2) (P < .001). Blood COHb (%) increased from a median of 1.3 (IQR, 1.0-1.8) to 1.7 (IQR, 1.3-2.2) (P < .001) following the OHCbl infusion. No differences were seen in median levels of tHb, PaO2, PaCO2, and SaO2 between pre- and post-OHCbl treatment. CONCLUSION: The presence of OHCbl in blood clearly interfered with the oximetry measurements of the hemoglobin component fractions by falsely increasing the levels of MetHb and COHb. Blood levels of MetHb and COHb cannot be reliably determined by the co-oximetry when OHCbl is known or suspected.


Asunto(s)
Hidroxocobalamina , Metahemoglobina , Humanos , Metahemoglobina/análisis , Hidroxocobalamina/uso terapéutico , Hemoglobinas/análisis , Oximetría , Carboxihemoglobina/análisis , Oxígeno
9.
J Phys Chem B ; 128(18): 4344-4353, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38688080

RESUMEN

Flavin mononucleotide (FMN) is a ubiquitous blue-light pigment due to its ability to drive one- and two-electron transfer reactions. In both light-oxygen-voltage (LOV) domains of phototropin from the green algae Chlamydomonas reinhardtii, FMN is noncovalently bound. In the LOV1 cysteine-to-serine mutant (C57S), light-induced electron transfer from a nearby tryptophan occurs, and a transient spin-correlated radical pair (SCRP) is formed. Within this photocycle, nuclear hyperpolarization is created by the solid-state photochemically induced dynamic nuclear polarization (photo-CIDNP) effect. In a side reaction, a stable protonated semiquinone radical (FMNH·) forms undergoing a significant bathochromic shift of the first electronic transition from 445 to 591 nm. The incorporation of phototropin LOV1-C57S into an amorphous trehalose matrix, stabilizing the radical, allows for application of various magnetic resonance experiments at ambient temperatures, which are combined with quantum-chemical calculations. As a result, the bathochromic shift of the first absorption band is explained by lifting the degeneracy of the molecular orbital energy levels for electrons with alpha and beta spins in FMNH· due to the additional electron.

10.
Chem Sci ; 14(23): 6295-6308, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37325146

RESUMEN

A large number of novel phytochromes named cyanobacteriochromes (CBCRs) have been recently identified. CBCRs appear to be attractive for further in-depth studies as paradigms for phytochromes because of their related photochemistry, but simpler domain architecture. Elucidating the mechanisms of spectral tuning for the bilin chromophore down to the molecular/atomic level is a prerequisite to design fine-tuned photoswitches for optogenetics. Several explanations for the blue shift during photoproduct formation associated with the red/green CBCRs represented by Slr1393g3 have been developed. There are, however, only sparse mechanistic data concerning the factors controlling stepwise absorbance changes along the reaction pathways from the dark state to the photoproduct and vice versa in this subfamily. Conventional cryotrapping of photocycle intermediates of phytochromes has proven experimentally intractable for solid-state NMR spectroscopy within the probe. Here, we have developed a simple method to circumvent this hindrance by incorporating proteins into trehalose glasses which allows four photocycle intermediates of Slr1393g3 to be isolated for NMR use. In addition to identifying the chemical shifts and chemical shift anisotropy principal values of selective chromophore carbons in various photocycle states, we generated QM/MM models of the dark state and photoproduct as well as of the primary intermediate of the backward-reaction. We find the motion of all three methine bridges in both reaction directions but in different orders. These molecular events channel light excitation to drive distinguishable transformation processes. Our work also suggests that polaronic self-trapping of a conjugation defect by displacement of the counterion during the photocycle would play a role in tuning the spectral properties of both the dark state and photoproduct.

11.
Biochim Biophys Acta Bioenerg ; 1864(4): 148996, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37437858

RESUMEN

Using ultrafast spectroscopy and site-specific mutagenesis, we demonstrate the central role of a conserved tyrosine within the chromophore binding pocket in the forward (Pr â†’ Pfr) photoconversion of phytochromes. Taking GAF1 of the knotless phytochrome All2699g1 from Nostoc as representative member of phytochromes, it was found that the mutations have no influence on the early (<30 ps) dynamics associated with conformational changes of the chromophore in the excited state. Conversely, they drastically impact the extended protein-controlled excited state decay (>100 ps). Thus, the steric demand, position and H-bonding capabilities of the identified tyrosine control the chromophore photoisomerization while leaving the excited state chromophore dynamics unaffected. In effect, this residue operates as an isomerization-steric-gate that tunes the excited state lifetime and the photoreaction efficiency by modulating the available space of the chromophore and by stabilizing the primary intermediate Lumi-R. Understanding the role of such a conserved structural element sheds light on a key aspect of phytochrome functionality and provides a basis for rational design of optimized photoreceptors for biotechnological applications.


Asunto(s)
Fenómenos Bioquímicos , Fitocromo , Fitocromo/genética , Fitocromo/metabolismo , Tirosina , Enlace de Hidrógeno , Análisis Espectral
12.
J Magn Reson ; 353: 107497, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37295281

RESUMEN

Hyperpolarization via the solid-state photochemically induced dynamic nuclear polarization (photo-CIDNP) effect can be detected in frozen solutions of electron transfer proteins generating a radical-pair upon illumination. The effect has been observed in various natural photosynthetic reaction centers and in light-oxygen-voltage (LOV) sensing domains incorporating a flavin mononucleotide (FMN) as chromophore. In LOV domains, where a highly conserved cysteine is mutated to a flavin to interrupt its natural photochemistry, a radical-pair is generated by electron transfer from a nearby tryptophan to the photoexcited triplet state of FMN. During the photocycle, both the LOV domain and the chromophore are photochemically degraded, e.g., by the formation of singlet oxygen. This limits the time for collection of hyperpolarized nuclear magnetic resonance (NMR) data. We show that embedding of the protein into a trehalose sugar glass matrix stabilizes the protein for 13C solid-state photo-CIDNP NMR experiments which can be conducted at room temperature in a powder sample. Additionally, this preparation allows for incorporation of high amounts of protein further boosting the intensity of the detected signals from FMN and tryptophan at natural abundance. Signal assignment is aided by quantum chemical calculations of absolute shieldings. The underlying mechanism for the surprising absorption-only signal pattern is not yet understood. Comparison to calculated isotropic hyperfine couplings imply that the enhancement is not due to the classical radical-pair mechanism (RPM). Analysis of the anisotropic hyperfine couplings associated with solid-state photo-CIDNP mechanisms also show no simple correlation, suggesting a more complex underlying mechanism.


Asunto(s)
Flavoproteínas , Azúcares , Temperatura , Triptófano , Espectroscopía de Resonancia Magnética
13.
J Pharm Pract ; 35(6): 1000-1006, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33960219

RESUMEN

BACKGROUND: Emerging data suggest that coagulopathy, cytokine storm, and acute respiratory distress syndrome are associated with the 2019 coronavirus disease (COVID-19). The prevalence of hypercoagulable state in these patients is unknown, but appears to be higher compared to those with other critically ill patients. Elevated D-dimer, large blood vessels clots, deep vein thrombosis, pulmonary embolism and disseminated intravascular coagulation have been reported in patients diagnosed with COVID-19 either on admission or during hospitalization and may be predictors of poor outcomes. METHODS: We performed a comprehensive literature review using the search terms of COVID-19; severe acute respiratory syndrome coronavirus-2, coagulopathy, thrombosis and anticoagulation in PubMed, Ovid, google scholar, Medline and EMBASE databases from December 2019 to May 30, 2020. RESULTS: A total of 64 relevant studies were reviewed; of which, 4 studies met the inclusion criteria and were included for analysis. The majority of the studies were retrospective involving 525 critically ill COVID-19 patients. The most commonly studied anticoagulant administered was low molecular weight heparins. Anticoagulation dosing varied throughout the studies and may be classified as standard venous thromboembolism prophylaxis, intermediate dosing, or full dose anticoagulation. The most studied objective was improvement in coagulopathy. Significant reduction in D-dimer, improvement in coagulopathy markers such as Interlukin-6, fibrinogen degradation product level, as well as lymphocyte count were reported. CONCLUSION: Despite the limited quality of studies analyzed, prophylaxis and higher intensity dosed anticoagulation is associated with improved pulmonary oxygenation, decreased coagulopathy markers and decreased mortality in COVID-19 patients.


Asunto(s)
Trastornos de la Coagulación Sanguínea , Tratamiento Farmacológico de COVID-19 , Trombosis , Humanos , SARS-CoV-2 , Enfermedad Crítica , Estudios Retrospectivos , Anticoagulantes/uso terapéutico , Trastornos de la Coagulación Sanguínea/tratamiento farmacológico , Trombosis/prevención & control
14.
J Phys Chem B ; 125(5): 1331-1342, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-33523656

RESUMEN

Cyanobacteriochromes (CBCRs) are photoreceptors of the phytochrome superfamily showing remarkable variability in the wavelengths of the first electronic transition-sometimes denoted as Q band-compared to canonical phytochromes. Both classes carry the same cofactor, a bilin, but the molecular basis for the wide variation of their absorption properties is still a matter of debate. The interaction between the cofactor and the surrounding protein moiety has been proposed as a possible tuning factor. Here, we address the impact of hydrogen-bonding interaction between the covalently bound tetrapyrrole cofactor (phycocyanobilin, PCB) and a conserved tyrosine residue (Y302) in the second GAF (cGMP-specific phosphodiesterase, adenylyl cyclases, and FhlA) domain of the red-/green-switching CBCR AnPixJ (AnPixJg2). In the wild type, AnPixJg2 shows absorption maxima of 648 and 543 nm for the dark-adapted (Pr) and photoproduct (Pg) states, respectively. The Y302F mutation leads to the occurrence of an additional absorption band at 687 nm, which is assigned to a new spectroscopically identified sub-state called PIII. Similar spectral changes result upon mutating the Y302F-homologue in another representative red-/green-switching CBCR, Slr1393g3. Molecular dynamics simulations on the dark-adapted state suggest that the removal of the hydrogen bond leads to an additional PCB sub-state differing in its A- and D-ring geometries. The origin of the Q band satellite in the dark-adapted state is discussed.


Asunto(s)
Cianobacterias , Fotorreceptores Microbianos , Fitocromo , Proteínas Bacterianas/genética , Pigmentos Biliares , Enlace de Hidrógeno , Fotorreceptores Microbianos/genética , Fitocromo/genética , Propionatos , Tirosina
15.
Anat Histol Embryol ; 50(3): 431-438, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33331012

RESUMEN

Equine paranasal sinuses are susceptible to inflammation. Insufficient drainage through the nasal passages and meatus may lead to the accumulation of inspissated purulent discharge. Particularly in ponies, these anatomical structures are suspected to be relatively small. To date, there are no reports considering the morphology of nasal conchal bullae in small horse breeds such as Shetland ponies. The aim of the present study was to evaluate the size of the conchal bullae and the medial nasal conchae of Shetland ponies and their relation to the skull dimension using computed tomography. Reconstructed images of healthy adult heads of Shetland ponies were used. Linear skull measurements as well as two cranial indices of the head dimensions were taken. Length, width and height of the dorsal and ventral conchal bullae and the medial nasal conchae were measured in relation to the skull and compared with the data of skulls of large breed horses. The anatomical proportions of pony heads were characterized by a smaller cranial index and a greater nasal index than those of large breed horses. Shetland ponies showed a longer cranial length compared with the nasal length. Heads are consistently smaller, and the relationship of the bullae to the head length was also smaller than those measured in large breed horses. A negative correlation between the head and bullae size was found. In conclusion, this study suggests that Shetland ponies have distinguishing proportions of the head. These findings are relevant for clinical examination and surgical treatment of equine sinus disease in those breeds.


Asunto(s)
Enfermedades de los Caballos , Senos Paranasales , Animales , Vesícula/veterinaria , Enfermedades de los Caballos/diagnóstico por imagen , Caballos , Cavidad Nasal/diagnóstico por imagen , Senos Paranasales/diagnóstico por imagen , Cornetes Nasales/diagnóstico por imagen
16.
Crit Care Explor ; 2(12): e0287, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33381763

RESUMEN

OBJECTIVES: Coagulopathy of coronavirus disease 2019 is largely described as hypercoagulability, yet both thrombotic and hemorrhagic complications occur. Although therapeutic and prophylactic anticoagulant interventions have been recommended, empiric use of antifactor medications (heparin/enoxaparin) may result in hemorrhagic complications, including death. Furthermore, traditional (antifactor) anticoagulation does not address the impact of overactive platelets in coronavirus disease 2019. The primary aim was to evaluate if algorithm-guided thromboelastography with platelet mapping could better characterize an individual's coronavirus disease 2019-relatedcoagulopathic state and, secondarily, improve outcomes. DESIGN SETTING AND PATIENTS: Coronavirus disease 2019 patients (n = 100), receiving thromboelastography with platelet mapping assay upon admission to an 800-bed tertiary-care hospital, were followed prospectively by a hospital-based thromboelastography team. Treating clinicians were provided with the option of using a pre-established algorithm for anticoagulation, including follow-up thromboelastography with platelet mapping assays. Two groups evolved: 1) patients managed by thromboelastography with platelet mapping algorithm (algorithm-guided-thromboelastography); 2) those treated without thromboelastography with platelet mapping protocols (non-algorithm-guided). Outcomes included thrombotic/hemorrhagic complications, pulmonary failure, need for mechanical ventilation, acute kidney injury, dialysis requirement, and nonsurvival. INTERVENTIONS: Standard-of-care therapy with or without algorithm-guided-thromboelastography support. MEASUREMENTS AND MAIN RESULTS: Although d-dimer, C-reactive protein, and ferritin were elevated significantly in critically ill (nonsurvivors, acute kidney injury, pulmonary failure), they did not distinguish between coagulopathic and noncoagulopathic patients. Platelet hyperactivity (maximum amplitude-arachidonic acid/adenosine diphosphate > 50 min), with or without thrombocytosis, was associated with thrombotic/ischemic complications, whereas severe thrombocytopenia (platelet count < 100,000/µL) was uniformly fatal. Hemorrhagic complications were observed with decreased factor activity (reaction time > 8 min). Non-algorithm-guided patients had increased risk for subsequent mechanical ventilation (relative risk = 10.9; p < 0.0001), acute kidney injury (relative risk = 2.3; p = 0.0017), dialysis (relative risk = 7.8; p < 0.0001), and death (relative risk = 7.7; p < 0.0001), with 17 of 28 non-algorithm-guided patients (60.7%) dying versus four algorithm-guided-thromboelastography patients (5.6%) (p < 0.0001). Thromboelastography with platelet mapping-guided antiplatelet treatment decreased mortality 82% (p = 0.0002), whereas non-algorithm-guided (compared with algorithm-guided-thromboelastography) use of antifactor therapy (heparin/enoxaparin) resulted in 10.3-fold increased mortality risk (p = 0.0001). CONCLUSIONS: Thromboelastography with platelet mapping better characterizes the spectrum of coronavirus disease 2019 coagulation-related abnormalities and may guide more tailored, patient-specific therapies in those infected with coronavirus disease 2019.

17.
Pediatr Rheumatol Online J ; 17(1): 37, 2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31286990

RESUMEN

BACKGROUND: Deficiency of interleukin-36 receptor antagonist (DITRA) is a life threatening monogenic autoinflammatory disease caused by loss of function mutations in the IL36RN gene. Affected patients develop recurrent episodes of generalized pustular psoriasis (GPP) with systemic inflammation and fever. We here review and analyze the literature on pediatric DITRA patients who have been treated by biologicals targeting inflammatory cytokines. METHOD: A database research was performed to identify all relevant articles on pediatric DITRA patients treated with biologicals. According to defined response criteria therapeutic efficacy was analyzed. RESULTS: Our literature research revealed 12 pediatric patients with DITRA who have received treatment with biologicals and we add a further not yet reported patient. Out of these 13 patients 10 were homozygous including 6 with the p.Leu27Pro, 3 with the p.Arg10 Argfs* and 1 with the p.Thr123Met mutation. 3 patients were compound heterozygous. In total 28 flares were treated with biological agents- targeting IL-1, IL-17, IL-12/23 and TNF-α. Complete response was achieved in 16 flares (57%), a partial reponse was seen in 2 flares (7%), and no response was observed in 10 flares (36%). Response rates were heterogeneous among the different agents. While complete/partial/no response with inhibition of TNF-alpha could be achieved in 7 (58%)/1 (8%)/4 (33%), the inhibition of IL-17 and of IL-12/23 led in each 4 flares to a 100% complete response. IL-1 inhibition led to complete/partial response in each 1 (13%) and was not effective in 6 (76%) flares. Of note, the novel patient was successfully treated with weekly dosed adalimumab. CONCLUSIONS: DITRA is a rare disease that has to be considered in GPP with systemic inflammation and fever. It can be effectively treated with specific biological inhibition of TNF-alpha, IL-12/23 and IL- 17, while anti-IL-1 treatment seems less effective. Weekly dosed adalimumab appears to be a treatment option for pediatric patients. Further reports and studies of biological treated pediatric DITRA patients are warranted for evaluation of optimal treatment.


Asunto(s)
Productos Biológicos/uso terapéutico , Proteína Antagonista del Receptor de Interleucina 1/genética , Receptores de Interleucina/deficiencia , Adolescente , Edad de Inicio , Niño , Preescolar , Femenino , Humanos , Lactante , Mutación con Pérdida de Función/genética , Masculino , Receptores de Interleucina/antagonistas & inhibidores , Resultado del Tratamiento
18.
Eur J Med Chem ; 182: 111588, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31421630

RESUMEN

Intrinsically disordered proteins are an emerging class of proteins without a folded structure and currently disorder-based drug targeting remains a challenge. p53 is the principal regulator of cell division and growth whereas MDM2 consists its main negative regulator. The MDM2-p53 recognition is a dynamic and multistage process that amongst other, employs the dissociation of a transient α-helical N-terminal ''lid'' segment of MDM2 from the proximity of the p53-complementary interface. Several small molecule inhibitors have been reported to inhibit the formation of the p53-MDM2 complex with the vast majority mimicking the p53 residues Phe19, Trp23 and Leu26. Recently, we have described the transit from the 3-point to 4-point pharmacophore model stabilizing this intrinsically disordered N-terminus by increasing the binding affinity by a factor of 3. Therefore, we performed a thorough SAR analysis, including chiral separation of key compound which was evaluated by FP and 2D NMR. Finally, p53-specific anti-cancer activity towards p53-wild-type cancer cells was observed for several representative compounds.


Asunto(s)
Antineoplásicos/farmacología , Proteínas Intrínsecamente Desordenadas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Bencilaminas/síntesis química , Bencilaminas/química , Bencilaminas/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cianuros/síntesis química , Cianuros/química , Cianuros/farmacología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Formiatos/síntesis química , Formiatos/química , Formiatos/farmacología , Humanos , Indoles/síntesis química , Indoles/química , Indoles/farmacología , Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/metabolismo , Estructura Molecular , Proteínas Proto-Oncogénicas c-mdm2/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Relación Estructura-Actividad , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/metabolismo
19.
Acad Forensic Pathol ; 7(4): 632-639, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31240012

RESUMEN

INTRODUCTION: The Summit County Medical Examiner's Office (SCMEO) observed 52 unexplained deaths during the month of July 2016 in which drug overdose was suspected. A fentanyl screening immunoassay performed on autopsy specimens was positive, but gas chromatograph/mass spectrometry (GC/MS) failed to confirm its presence. Carfentanil, a large wildlife tranquilizer, was later identified through reference lab testing as the cause of the sudden increase in overdoses. METHODS: Due to the large volume of cases which followed, a method for identifying carfentanil was developed utilizing in-house instrumentation. In addition, a retrospective analysis for all drug overdose cases was conducted through the SCMEO database from January 2009 through December 2016. RESULTS: Assessment of the data revealed a 277% increase in yearly overdose-related fatalities when comparing 2009 to 2016. Carfentanil was not identified in any other fatal drug overdoses in the area before the first appearance in Akron in July of 2016. There was an initial spike of 35 deaths in both July and August, which then decreased to 12 deaths in December. There was an almost equal distribution of carfentanil as a single agent and carfentanil mixed with multiple other illicit drugs. DISCUSSION: Current observations suggest carfentanil concentrations in overdose cases are decreasing; however, it may be present in combination with other drugs, especially other fentanyl analogs. The lower concentrations of carfentanil are much more difficult to detect in urine and peripheral blood, therefore making the testing of scene paraphernalia, central blood, and organ tissue more of a necessity.

20.
GMS J Med Educ ; 34(3): Doc30, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28890921

RESUMEN

Introduction: One of the most important extracurricular aspects of medical studies in Germany is a research thesis completed by most students. This research project often times conveys relevant competencies for the physician's role as scientist. Nevertheless, the choice of the right project remains a challenge. Reasons for this are among others, missing structures for a comprehensive overview of research groups and their respective projects. Description of the project: We developed the online platform Doktabörse as an online marketplace for doctoral research projects. The platform enables authorized researchers to create working groups and upload, deactivate and change research projects within their institute. For interested students, a front end with integrated search function displays these projects in a structured and well-arranged way. In parallel, the Doktabörse provides for a comprehensive overview of research at the medical faculty. We evaluated Researchers' and students' use of the platform. Results: 96,6% of students participating in the evaluation (n=400) were in favor of a centralized research platform at the medical faculty. The platform grew at a steady pace and included 120 research groups in June 2016. The students appreciated the structure and design of the Doktabörse. Two thirds of all uploaded projects matched successfully with doctoral students via the platform and over 94% of researchers stated that they did not need technical assistance with uploading projects and handling the platform. Discussion: The Doktabörse represents an innovative and well accepted platform for doctoral research projects. The platform is perceived positively by researchers and students alike. However, students criticized limited extent and timeliness of offered projects. In addition, the platform serves as databank of research at the medical faculty of the LMU Munich. The future potential of this platform is to provide for an integrated management solution of doctoral thesis projects, possibly beyond the medical field and faculty.


Asunto(s)
Tesis Académicas como Asunto , Investigación Biomédica , Bases de Datos como Asunto , Docentes Médicos , Hospitales Universitarios , Internet , Diseño de Software , Competencia Clínica , Curriculum , Alemania , Humanos , Rol del Médico
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