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BACKGROUND: Recent studies have highlighted Coronavirus disease 2019 (COVID-19) as a multisystemic vascular disease. Up to 60% of the patients suffer from long-term sequelae and persistent symptoms even 6 months after the initial infection. METHODS: This prospective, observational study included 58 participants, 27 of whom were long COVID patients with persistent symptoms > 12 weeks after recovery from PCR-confirmed SARS-CoV-2 infection. Fifteen healthy volunteers and a historical cohort of critically ill COVID-19 patients (n = 16) served as controls. All participants underwent sublingual videomicroscopy using sidestream dark field imaging. A newly developed version of Glycocheck™ software was used to quantify vascular density, perfused boundary region (PBR-an inverse variable of endothelial glycocalyx dimensions), red blood cell velocity (VRBC) and the microvascular health score (MVHS™) in sublingual microvessels with diameters 4-25 µm. MEASUREMENTS AND MAIN RESULTS: Although dimensions of the glycocalyx were comparable to those of healthy controls, a µm-precise analysis showed a significant decrease of vascular density, that exclusively affected very small capillaries (D5: - 45.16%; D6: - 35.60%; D7: - 22.79%). Plotting VRBC of capillaries and feed vessels showed that the number of capillaries perfused in long COVID patients was comparable to that of critically ill COVID-19 patients and did not respond adequately to local variations of tissue metabolic demand. MVHS was markedly reduced in the long COVID cohort (healthy 3.87 vs. long COVID 2.72 points; p = 0.002). CONCLUSIONS: Our current data strongly suggest that COVID-19 leaves a persistent capillary rarefication even 18 months after infection. Whether, to what extent, and when the observed damage might be reversible remains unclear.
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COVID-19 , Capilares , Humanos , Síndrome Post Agudo de COVID-19 , Estudios Prospectivos , Enfermedad Crítica , COVID-19/metabolismo , SARS-CoV-2 , Glicocálix , MicrocirculaciónRESUMEN
S-Adenosylmethionine (SAM) is an enzyme cofactor involved in methylation, aminopropyl transfer, and radical reactions. This versatility renders SAM-dependent enzymes of great interest in biocatalysis. The usage of SAM analogues adds to this diversity. However, high cost and instability of the cofactor impedes the investigation and usage of these enzymes. While SAM regeneration protocols from the methyltransferase (MT) byproduct S-adenosylhomocysteine are available, aminopropyl transferases and radical SAM enzymes are not covered. Here, we report a set of efficient one-pot systems to supply or regenerate SAM and SAM analogues for all three enzyme classes. The systems' flexibility is showcased by the transfer of an ethyl group with a cobalamin-dependent radical SAM MT using S-adenosylethionine as a cofactor. This shows the potential of SAM (analogue) supply and regeneration for the application of diverse chemistry, as well as for mechanistic studies using cofactor analogues.
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Biomimética , S-Adenosilmetionina , S-Adenosilmetionina/metabolismo , Biocatálisis , Alquilación , Metilación , Metiltransferasas/metabolismoRESUMEN
Chemical modification of small molecules is a key step for the development of pharmaceuticals. S-adenosyl-l-methionine (SAM) analogues are used by methyltransferases (MTs) to transfer alkyl, allyl and benzyl moieties chemo-, stereo- and regioselectively onto nucleophilic substrates, enabling an enzymatic way for specific derivatisation of a wide range of molecules. l-Methionine analogues are required for the synthesis of SAM analogues. Most of these are not commercially available. In nature, O-acetyl-l-homoserine sulfhydrolases (OAHS) catalyse the synthesis of l-methionine from O-acetyl-l-homoserine or l-homocysteine, and methyl mercaptan. Here, we investigated the substrate scope of ScOAHS from Saccharomyces cerevisiae for the production of l-methionine analogues from l-homocysteine and organic thiols. The promiscuous enzyme was used to synthesise nine different l-methionine analogues with modifications on the thioether residue up to a conversion of 75 %. ScOAHS was combined with an established MT dependent three-enzyme alkylation cascade, allowing transfer of in total seven moieties onto two MT substrates. For ethylation, conversion was nearly doubled with the new four-enzyme cascade, indicating a beneficial effect of the inâ situ production of l-methionine analogues with ScOAHS.
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Metionina , Metiltransferasas , Metiltransferasas/metabolismo , Homoserina , S-Adenosilmetionina/química , Alquilación , Catálisis , HomocisteínaRESUMEN
In mass spectrometry (MS)-based metabolomics, there is a great need to combine different analytical separation techniques to cover metabolites of different polarities and apply appropriate multi-platform data processing. Here, we introduce AriumMS (augmented region of interest for untargeted metabolomics mass spectrometry) as a reliable toolbox for multi-platform metabolomics. AriumMS offers augmented data analysis of several separation techniques utilizing a region-of-interest algorithm. To demonstrate the capabilities of AriumMS, five datasets were combined. This includes three newly developed capillary electrophoresis (CE)-Orbitrap MS methods using the recently introduced nanoCEasy CE-MS interface and two hydrophilic interaction liquid chromatography (HILIC)-Orbitrap MS methods. AriumMS provides a novel mid-level data fusion approach for multi-platform data analysis to simplify and speed up multi-platform data processing and evaluation. The key feature of AriumMS lies in the optimized data processing strategy, including parallel processing of datasets and flexible parameterization for processing of individual separation methods with different peak characteristics. As a case study, Saccharomyces cerevisiae (yeast) was treated with a growth inhibitor, and AriumMS successfully differentiated the metabolome based on the augmented multi-platform CE-MS and HILIC-MS investigation. As a result, AriumMS is proposed as a powerful tool to improve the accuracy and selectivity of metabolome analysis through the integration of several HILIC-MS/CE-MS techniques.
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Metabolómica , Espectrometría de Masas en Tándem , Cromatografía Liquida/métodos , Metabolómica/métodos , Metaboloma , Electroforesis Capilar/métodosRESUMEN
CYTH proteins make up a large superfamily that is conserved in all three domains of life. These enzymes have a triphosphate tunnel metalloenzyme (TTM) fold, which typically results in phosphatase functions, e.g., RNA triphosphatase, inorganic polyphosphatase, or thiamine triphosphatase. Some CYTH orthologs cyclize nucleotide triphosphates to 3',5'-cyclic nucleotides. So far, archaeal CYTH proteins have been annotated as adenylyl cyclases, although experimental evidence to support these annotations is lacking. To address this gap, we characterized a CYTH ortholog, SaTTM, from the crenarchaeote Sulfolobus acidocaldarius. Our in silico studies derived ten major subclasses within the CYTH family implying a close relationship between these archaeal CYTH enzymes and class IV adenylyl cyclases. However, initial biochemical characterization reveals inability of SaTTM to produce any cyclic nucleotides. Instead, our structural and functional analyses show a classical TTM behavior, i.e., triphosphatase activity, where pyrophosphate causes product inhibition. The Ca2+-inhibited Michaelis complex indicates a two-metal-ion reaction mechanism analogous to other TTMs. Cocrystal structures of SaTTM further reveal conformational dynamics in SaTTM that suggest feedback inhibition in TTMs due to tunnel closure in the product state. These structural insights combined with further sequence similarity network-based in silico analyses provide a firm molecular basis for distinguishing CYTH orthologs with phosphatase activities from class IV adenylyl cyclases.
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Archaea/enzimología , Proteínas Arqueales/química , Proteínas Arqueales/metabolismo , Familia de Multigenes , Polifosfatos/metabolismo , Adenilil Ciclasas/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Biocatálisis , Iones , Modelos Moleculares , Multimerización de Proteína , Especificidad por Sustrato , Sulfolobus acidocaldarius/enzimología , AguaRESUMEN
PURPOSE: To develop and validate a novel score to more objectively assess the performance of diagnostic knee arthroscopy using a simulator. METHODS: A Diagnostic Arthroscopy Skill Score (DASS) was developed by ten AGA (AGA-Society for Arthroscopy and Joint-Surgery) instructors for the assessment of arthroscopic skills. DASS consists of two parts: the evaluation of standardized diagnostic knee arthroscopy (DASSpart1) and the evaluation of manual dexterity, including ambidexterity and triangulation, using objective measurement parameters (DASSpart2). Content validity was determined by the Delphi method. One hundred and eleven videos of diagnostic knee arthroscopies were recorded during simulator training courses and evaluated by six specially trained instructors using DASS. Construct validity, measurement error calculated by the minimum detectable change (MDC), internal consistency using Cronbach's alpha and interrater and intrarater reliability were assessed. The Bland-Altman method was used to calculate the intrarater agreement. RESULTS: Six skill domains were identified and evaluated for each knee compartment. DASS, DASSpart1, and DASSpart2 showed construct validity, with experts achieving significantly higher scores than competents and novices. MDC was 4.5 ± 1.7 points for DASSpart1. There was high internal consistency for all domains in each compartment from 0.78 to 0.86. The interrater reliability showed high agreement between the six raters (ICC = 0.94). The evaluation of intrarater reliability demonstrated good and excellent agreement for five raters (ICC > 0.80) and moderate agreement for one rater (ICC = 0.68). The Bland-Altman comparison showed no difference between the first and second evaluations in five out of six raters. Precision, estimated by the regression analysis and comparison with the method of Bland and Altman, was excellent for four raters and moderate for two raters. CONCLUSIONS: The results of this study indicate good validity and reliability of DASS for the assessment of the surgical performance of diagnostic knee arthroscopy during simulator training. Standardized training is recommended before arthroscopy surgery is considered in patients. LEVEL OF EVIDENCE: II.
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Artroscopía , Internado y Residencia , Competencia Clínica , Humanos , Articulación de la Rodilla/cirugía , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: Simulator arthroscopy training has gained popularity in recent years. However, it remains unclear what level of competency surgeons may achieve in what time frame using virtual training. It was hypothesized that 10 h of training would be sufficient to reach the target level defined by experts based on the Diagnostic Arthroscopic Skill Score (DASS). METHODS: The training concept was developed by ten instructors affiliated with the German-speaking Society of Arthroscopy and Joint Surgery (AGA). The programme teaches the basics of performing arthroscopy; the main focus is on learning and practicing manual skills using a simulator. The training was based on a structured programme of exercises designed to help users reach defined learning goals. Initially, camera posture, horizon adjustment and control of the direction of view were taught in a virtual room. Based on these skills, further training was performed with a knee model. The learning progress was assessed by quantifying the exercise time, camera path length and instrument path length for selected tasks. At the end of the course, the learners' performance in diagnostic arthroscopy was evaluated using DASS. Participants were classified as novice or competent based on the number of arthroscopies performed prior to the assessment. RESULTS: Except for one surgeon, 131 orthopaedic residents and surgeons (29 women, 102 men) who participated in the seven courses agreed to anonymous data analysis. Fifty-eight of them were competents with more than ten independently performed arthroscopies, and 73 were novices, with fewer than ten independently performed arthroscopies. There were significant reductions in exercise time, camera path length and instrument path length for all participants after the training, indicating a rapid increase in performance. No difference in camera handling between the dominant and non-dominant sides was found in either group. The competents performed better than the novices in various tasks and achieved significantly better DASS values on the final performance test. CONCLUSIONS: Our data have demonstrated that arthroscopic skills can be taught effectively on a simulator, but a 10-h course is not sufficient to reach the target level set by experienced arthroscopists. However, learning progress can be monitored more objectively during simulator training than in the operating room, and simulation may partially replace the current practice of arthroscopic training. LEVEL OF EVIDENCE: III.
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Internado y Residencia , Ortopedia , Entrenamiento Simulado , Artroscopía/educación , Competencia Clínica , Femenino , Humanos , Articulación de la Rodilla/cirugía , Masculino , Ortopedia/educaciónRESUMEN
Regulation of enzyme activity is vital for living organisms. In metalloenzymes, far-reaching rearrangements of the protein scaffold are generally required to tune the metal cofactor's properties by allosteric regulation. Here structural analysis of hydroxyketoacid aldolase from Sphingomonas wittichii RW1 (SwHKA) revealed a dynamic movement of the metal cofactor between two coordination spheres without protein scaffold rearrangements. In its resting state configuration (M2+ R ), the metal constitutes an integral part of the dimer interface within the overall hexameric assembly, but sterical constraints do not allow for substrate binding. Conversely, a second coordination sphere constitutes the catalytically active state (M2+ A ) at 2.4â Å distance. Bidentate coordination of a ketoacid substrate to M2+ A affords the overall lowest energy complex, which drives the transition from M2+ R to M2+ A . While not described earlier, this type of regulation may be widespread and largely overlooked due to low occupancy of some of its states in protein crystal structures.
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Metaloproteínas , Metaloproteínas/química , Metales , Fructosa-Bifosfato Aldolasa/metabolismo , Regulación AlostéricaRESUMEN
BACKGROUND AND OBJECTIVE: The clinical relevance and interrelation of sleep-disordered breathing and nocturnal hypoxemia in patients with precapillary pulmonary hypertension (PH) is not fully understood. METHODS: Seventy-one patients with PH (age 63 ± 15 years, 41% male) and 35 matched controls were enrolled. Patients with PH underwent clinical examination with assessment of sleep quality, daytime sleepiness, 6-minute walk distance (6MWD), overnight cardiorespiratory polygraphy, lung function, hypercapnic ventilatory response (HCVR; by rebreathing technique), amino-terminal pro-brain natriuretic peptide (NT-proBNP) levels, and cardiac MRI (n = 34). RESULTS: Prevalence of obstructive sleep apnea (OSA) was 68% in patients with PH (34% mild, apnea-hypopnea index [AHI] ≥5 to <15/h; 34% moderate to severe, AHI ≥15/h) versus 5% in controls (p < 0.01). Only 1 patient with PH showed predominant central sleep apnea (CSA). Nocturnal hypoxemia (mean oxygen saturation [SpO2] <90%) was present in 48% of patients with PH, independent of the presence of OSA. There were no significant differences in mean nocturnal SpO2, self-reported sleep quality, 6MWD, HCVR, and lung and cardiac function between patients with moderate to severe OSA and those with mild or no OSA (all p > 0.05). Right ventricular (RV) end-diastolic (r = -0.39; p = 0.03) and end-systolic (r = -0.36; p = 0.04) volumes were inversely correlated with mean nocturnal SpO2 but not with measures of OSA severity or daytime clinical variables. CONCLUSION: OSA, but not CSA, is highly prevalent in patients with PH, and OSA severity is not associated with nighttime SpO2, clinical and functional status. Nocturnal hypoxemia is a frequent finding and (in contrast to OSA) relates to structural RV remodeling in PH.
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Hipertensión Pulmonar , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Anciano , Femenino , Humanos , Hipertensión Pulmonar/complicaciones , Hipoxia/diagnóstico , Hipoxia/epidemiología , Hipoxia/etiología , Masculino , Persona de Mediana Edad , Polisomnografía , Prevalencia , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/epidemiología , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/epidemiologíaRESUMEN
BACKGROUND: In precapillary pulmonary hypertension (PH), nasal high flow therapy (NHF) may favorably alter sympathovagal balance (SVB) and sleep-related breathing through washout of anatomical dead space and alleviation of obstructive sleep apnea (OSA) due to generation of positive airway pressure. OBJECTIVES: To investigate the effects of NHF on SVB, sleep, and OSA in patients with PH, and compare them with those of positive airway pressure therapy (PAP). METHODS: Twelve patients with PH (Nice class I or IV) and confirmed OSA underwent full polysomnography, and noninvasive monitoring of SVB parameters (spectral analysis of heart rate, diastolic blood pressure variability). Study nights were randomly split into four 2-h segments with no treatment, PAP, NHF 20 L/min, or NHF 50 L/min. In-depth SVB analysis was conducted on 10-min epochs during daytime and stable N2 sleep at nighttime. RESULTS: At daytime and compared with no treatment, NHF20 and NHF50 were associated with a flow-dependent increase in peripheral oxygen saturation but a shift in SVB towards increased sympathetic drive. At nighttime, NHF20 was associated with increased parasympathetic drive and improvements in sleep efficiency, but did not alter OSA severity. NHF50 was poorly tolerated. PAP therapy improved OSA but had heterogenous effects on SVB and neutral effects on sleep outcomes. Hemodynamic effects were neutral for all interventions. CONCLUSIONS: In sleeping PH patients with OSA NHF20 but not NHF50 leads to decreased sympathetic drive likely due to washout of anatomical dead space. NHF was not effective in lowering the apnea-hypopnoea index and NHF50 was poorly tolerated.
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Presión Sanguínea/fisiología , Frecuencia Cardíaca/fisiología , Hipertensión Pulmonar/terapia , Terapia por Inhalación de Oxígeno/métodos , Apnea Obstructiva del Sueño/terapia , Sueño/fisiología , Anciano , Femenino , Humanos , Hipertensión Pulmonar/fisiopatología , Masculino , Persona de Mediana Edad , Polisomnografía , Apnea Obstructiva del Sueño/fisiopatología , Resultado del TratamientoRESUMEN
BACKGROUND: In lung transplant recipients (LTRs), restrictive ventilation disorder may be present due to respiratory muscle dysfunction that may reduce exercise capacity. This might be mediated by pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). OBJECTIVE: We investigated lung respiratory muscle function as well as circulating pro-inflammatory cytokines and exercise capacity in LTRs. METHODS: Fifteen LTRs (6 female, age 56 ± 14 years, 63 ± 45 months post-transplantation) and 15 healthy controls matched for age, sex, and body mass index underwent spirometry, measurement of mouth occlusion pressures, diaphragm ultrasound, and recording of twitch transdiaphragmatic (twPdi) and gastric pressures (twPgas) following magnetic stimulation of the phrenic nerves and the lower thoracic nerve roots. Exercise capacity was quantified using the 6-min walking distance (6MWD). Plasma IL-6 and TNF-α were measured using enzyme-linked immunosorbent assays. RESULTS: Compared with controls, patients had lower values for forced vital capacity (FVC; 81 ± 30 vs.109 ± 18% predicted, p = 0.01), maximum expiratory pressure (100 ± 21 vs.127 ± 17 cm H2O, p = 0.04), diaphragm thickening ratio (2.2 ± 0.4 vs. 3.0 ± 1.1, p = 0.01), and twPdi (10.4 ± 3.5 vs. 17.6 ± 6.7 cm H2O, p = 0.01). In LTRs, elevation of TNF-α was related to lung function (13 ± 3 vs. 11 ± 2 pg/mL in patients with FVC ≤80 vs. >80% predicted; p < 0.05), and lung function (forced expiratory volume after 1 s) was closely associated with diaphragm thickening ratio (r = 0.81; p < 0.01) and 6MWD (r = 0.63; p = 0.02). CONCLUSION: There is marked restrictive ventilation disorder and respiratory muscle weakness in LTRs, especially inspiratory muscle weakness with diaphragm dysfunction. Lung function impairment relates to elevated levels of circulating TNF-α and diaphragm dysfunction and is associated with exercise intolerance.
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Diafragma/diagnóstico por imagen , Tolerancia al Ejercicio/fisiología , Interleucina-6/sangre , Trasplante de Pulmón , Fuerza Muscular/fisiología , Complicaciones Posoperatorias/fisiopatología , Trastornos Respiratorios/fisiopatología , Factor de Necrosis Tumoral alfa/sangre , Adulto , Anciano , Fibrosis Quística/cirugía , Diafragma/fisiopatología , Femenino , Humanos , Masculino , Presiones Respiratorias Máximas , Persona de Mediana Edad , Complicaciones Posoperatorias/sangre , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Fibrosis Pulmonar/cirugía , Trastornos Respiratorios/sangre , Músculos Respiratorios , Capacidad Vital , Prueba de PasoRESUMEN
PURPOSE: Pulse transit time (PTT) derived by ECG and plethysmographic signal can be a promising alternative to invasive or oscillometry-based blood pressure (BP) monitoring in sleep laboratories because it does not cause arousals from sleep. Therefore, this study assessed the validity of PTT for BP monitoring under sleep laboratory-like conditions. METHODS: Ten volunteers (55.8 ± 19.6 years), 12 patients with heart failure with reduced ejection fraction (HFrEF; 67.3 ± 8.6 years), and 14 patients with Nizza class I pulmonary arterial hypertension (PAH; 59.5 ± 13.4 years) performed different breathing patterns to simulate nocturnal sleep-disordered breathing (SDB). BP was measured at least every 15 min over 1 h using oscillometry (Task Force Monitor™) and PTT (SOMNOscreen™) devices in free breathing conditions and during SDB simulation (alternating phases of hyperventilation and apneas). RESULTS: One hundred forty-two points of measurements were collected. No difference was found in both mean systolic BP (SBP) and diastolic BP (DBP) between oscillometric PTT-based BP measurements in the whole population and throughout the whole recording (SBP 111.3 ± 15.1 mmHg versus 110.0 ± 14.7 mmHg, p = 0.051; DBP 69.9 ± 12.2 versus 69.9 ± 14.2 mmHg, p = 0.701). Likewise, no significant difference in SBP and DBP was found between the two methods in the subgroups of healthy subjects, HFrEF patients and PAH patients, both in free breathing conditions (p > 0.05) and during SDB simulation (p > 0.05). CONCLUSIONS: When monitoring BP in healthy subjects, and in patients with HFrEF or PAH, PTT provides a BP estimation comparable with oscillometric measurement, though slightly inaccurate, both in the condition of regular and unstable breathing.
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Presión Sanguínea/fisiología , Insuficiencia Cardíaca/fisiopatología , Hipertensión Pulmonar/fisiopatología , Polisomnografía/métodos , Análisis de la Onda del Pulso/métodos , Trabajo Respiratorio/fisiología , Adulto , Anciano , Nivel de Alerta/fisiología , Gasto Cardíaco Bajo/fisiopatología , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oscilometría/instrumentación , Oscilometría/métodos , Pletismografía/instrumentación , Pletismografía/métodos , Polisomnografía/instrumentación , Análisis de la Onda del Pulso/instrumentación , Reproducibilidad de los ResultadosRESUMEN
After the publication of the original manuscript we found that the calculation of the supplemental data regarding the capacity of PTT-based blood pressure (BP) recordings to detect changes in systolic and diastolic BP in different cohorts of patients was incorrect. These errors occured when data were transformed from MS Excel to Sigma-Plot tables. In this correction, the affected data and the respective figures were now revised.
RESUMEN
Polyphosphate kinases (PPKs) are involved in many metabolic processes; enzymes of the second family (PPK2) are responsible for nucleotide synthesis fuelled by the consumption of inorganic polyphosphate. They catalyse the phosphorylation of nucleotides with various numbers of phosphate residues, such as monophosphates or diphosphates. Hence, these enzymes are promising candidates for cofactor regeneration systems. Besides adenosine 5'-triphosphate, PPK2s also catalyse the synthesis of highly phosphorylated nucleotides in vitro, as shown here for adenosine 5'-tetraphosphate and adenosine 5'-pentaphosphate. These unusually phosphorylated adenosine 5'-polyphosphates add up to 50 % of the whole adenosine nucleotides in the assay. The two new products were chemically synthesised to serve as standards and compared with the two enzymatically produced compounds by high-performance ion chromatography and 31 Pâ NMR analysis. This study shows that PPK2s are highly suitable for biocatalytic synthesis of different phosphorylated nucleotides.
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Adenosina Monofosfato/metabolismo , Fosfotransferasas (Aceptor del Grupo Fosfato)/metabolismo , Polifosfatos/metabolismo , Adenosina Monofosfato/química , Catálisis , Especificidad por SustratoRESUMEN
BACKGROUND: The effects of hyperventilation and hyperventilation in the context of periodic breathing (PB) on sympatho-vagal balance (SVB) and hemodynamics in conditions of decreased cardiac output and feedback resetting, such as heart failure (HF) or pulmonary arterial hypertension (PAH), are not completely understood. OBJECTIVES: To investigate the effects of voluntary hyperventilation and simulated PB on hemodynamics and SVB in healthy subjects, in patients with systolic HF and reduced or mid-range ejection fraction (HFrEF and HFmrEF) and in patients with PAH. METHODS: Study participants (n = 20 per group) underwent non-invasive recording of diastolic blood pressure, heart rate variability (HRV), baroreceptor-reflex sensitivity (BRS), total peripheral resistance index (TPRI) and cardiac index (CI). All measurements were performed at baseline, during voluntary hyperventilation and during simulated PB with different length of the hyperventilation phase. RESULTS: In healthy subjects, voluntary hyperventilation led to a 50% decrease in the mean BRS slope and a 29% increase in CI compared to baseline values (p < 0.01 and p < 0.05). Simulated PB did not alter TPRI or CI and showed heterogeneous effects on BRS, but analysis of dPBV revealed decreased sympathetic drive in healthy volunteers depending on PB cycle length (p < 0.05). In HF patients, hyperventilation did not affect BRS and TPRI but increased the CI by 10% (p < 0.05). In HF patients, simulated PB left all of these parameters unaffected. In PAH patients, voluntary hyperventilation led to a 15% decrease in the high-frequency component of HRV (p < 0.05) and a 5% increase in CI (p < 0.05). Simulated PB exerted neutral effects on both SVB and hemodynamic parameters. CONCLUSIONS: Voluntary hyperventilation was associated with sympathetic predominance and CI increase in healthy volunteers, but only with minor hemodynamic and SVB effects in patients with HF and PAH. Simulated PB had positive effects on SVB in healthy volunteers but neutral effects on SVB and hemodynamics in patients with HF or PAH.
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Barorreflejo/fisiología , Insuficiencia Cardíaca/complicaciones , Hemodinámica/fisiología , Hiperventilación/fisiopatología , Hipertensión Arterial Pulmonar/fisiopatología , Volumen Sistólico/fisiología , Adulto , Sistema Nervioso Autónomo/fisiología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , RespiraciónRESUMEN
Histoplasmosis in central Europe is a rare fungal disease with diverse clinical presentations. Apart from acute pulmonary histoplasmosis and involvement of the central nervous system, the most serious clinical presentation is progressive disseminated histoplasmosis which is generally associated with severe immunodeficiency and, in particular, advanced human immunodeficiency virus infection. Here, we report on an immunocompetent female residing in a non-endemic area, presenting with progressive disseminated histoplasmosis after a remote travel history to Thailand and Costa Rica. Diagnosis was delayed by several months due to misinterpretation of epithelioid cell granulomatosis of the intestine as Crohn's disease and of similar lung lesions as acute sarcoidosis. Prompted by clinical deterioration with signs and symptoms consistent with hemophagocytic lymphohistiocytosis, a bone marrow aspiration was performed that documented hemophagocytosis and intracellular organisms interpreted as Leishmania sp., but later identified by molecular methods as Histoplasma capsulatum. Treatment with liposomal amphotericin B followed by posaconazole led to prompt clinical improvement and ultimately cure.
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Células Epitelioides/patología , Histoplasmosis/complicaciones , Histoplasmosis/diagnóstico , Linfohistiocitosis Hemofagocítica/complicaciones , Linfohistiocitosis Hemofagocítica/diagnóstico , Biomarcadores , Biopsia , Médula Ósea/patología , Endoscopía , Femenino , Humanos , Ganglios Linfáticos/patología , Linfohistiocitosis Hemofagocítica/terapia , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos XRESUMEN
PURPOSE: Candida induced spondylodiscitis of the cervical spine in immunocompetent patients is an extremely rare infectious complication. Since clinical symptoms might be nonspecific, therapeutic latency can lead to permanent spinal cord damage, sepsis and fatal complications. Surgical debridement is strongly recommended but there is no standard antimycotic regime for postsurgical treatment. This paper summarizes available data and demonstrates another successfully treated case. METHODS: The systematic analysis was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. PubMed and Web of Science were scanned to identify English language articles. Additionally, the authors describe the case of a 60-year-old male patient who presented with a Candida albicans induced cervical spondylodiscitis after an edematous pancreatitis and C. albicans sepsis. Anterior cervical corpectomy and fusion of C4-C6, additional anterior plating, as well as posterior stabilization C3-Th1 was followed by a 6-month antimycotic therapy. There was neither funding nor conflict of interests. RESULTS: A systematic literature analysis was conducted and 4599 articles on spondylodiscitis were scanned. Only four cases were found reporting about a C. albicans spondylodiscitis in a non-immunocompromised patient. So far, our patient was followed up for 2 years. Until now, he shows free of symptoms and infection parameters. Standard testing for immunodeficiency showed no positive results. CONCLUSION: Candida albicans spondylodiscitis of the cervical spine presents a potentially life-threatening disease. To our knowledge, this is the fifth case in literature that describes the treatment of C. albicans spondylodiscitis in an immunocompetent patient. Surgical debridement has to be considered, following antimycotic regime recommendations vary in pharmaceutical agents and treatment duration.
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Antifúngicos/uso terapéutico , Candidiasis/terapia , Vértebras Cervicales/cirugía , Discitis/terapia , Fusión Vertebral/métodos , Candida albicans , Candidiasis/diagnóstico por imagen , Desbridamiento/métodos , Discitis/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Espondilitis/terapia , Tomografía Computarizada por Rayos XAsunto(s)
Insuficiencia Cardíaca , Tolerancia al Ejercicio , Humanos , Consumo de Oxígeno , Volumen SistólicoRESUMEN
Sarcoidosis is a multisystem disorder of unknown etiology. The leading hypothesis involves an antigen-triggered dysregulated T-cell-driven immunologic response leading to non-necrotic granulomas. In cardiac sarcoidosis (CS), the inflammatory response can lead to fibrosis, culminating in clinical manifestations such as atrioventricular block and ventricular arrhythmias. Cardiac manifestations frequently present as first and isolated signs or may appear in conjunction with extracardiac manifestations. The incidence of sudden cardiac death (SCD) is high. Diagnosis remains a challenge. For a definite diagnosis, endomyocardial biopsy (EMB) is suggested. In clinical practice, compatible findings in advanced imaging using cardiovascular magnetic resonance (CMR) and/or positron emission tomography (PET) in combination with extracardiac histological proof is considered sufficient. Management revolves around the control of myocardial inflammation by employing immunosuppression. However, data regarding efficacy are merely based on observational evidence. Prevention of SCD is of particular importance and several guidelines provide recommendations regarding device therapy. In patients with manifest CS, outcome data indicate a 5-year survival of around 90% and a 10-year survival in the range of 80%. Data for patients with silent CS are conflicting; some studies suggest an overall benign course of disease while others reported contrasting observations. Future research challenges involve better understanding of the immunologic pathogenesis of the disease for a targeted therapy, improving imaging to aid early diagnosis, assessing the need for screening of asymptomatic patients and randomized trials.