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1.
BMC Neurol ; 24(1): 229, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961320

ABSTRACT

Cryptococcal meningitis (CM) is a severe fungal disease in immunocompromised patients affecting the central nervous system (CNS). Host response and immunological alterations in the cerebrospinal fluid (CSF) after invasion of Cryptococcus neoformans to the central nervous system have been investigated before but rigorous and comprehensive studies examining cellular changes in the CSF of patients with cryptococccal meningitis are still rare. We retrospectively collected CSF analysis and flow cytometry data of CSF and blood in patients with CM (n = 7) and compared them to HIV positive patients without meningitis (n = 13) and HIV negative healthy controls (n = 7). Within the group of patients with CM we compared those with HIV infection (n = 3) or other immunocompromised conditions (n = 4). Flow cytometry analysis revealed an elevation of natural killer cells and natural killer T cells in the CSF and blood of HIV negative patients with CM, pointing to innate immune activation in early stages after fungal invasion. HIV positive patients with CM exhibited stronger blood-CSF-barrier disruption. Follow-up CSF analysis over up to 150 days showed heterogeneous cellular courses in CM patients with slow normalization of CSF after induction of antifungal therapy.


Subject(s)
Antifungal Agents , Meningitis, Cryptococcal , Humans , Meningitis, Cryptococcal/cerebrospinal fluid , Meningitis, Cryptococcal/immunology , Meningitis, Cryptococcal/drug therapy , Male , Female , Adult , Middle Aged , Antifungal Agents/therapeutic use , Retrospective Studies , Killer Cells, Natural/immunology , Killer Cells, Natural/drug effects , Aged , Flow Cytometry , HIV Infections/drug therapy , HIV Infections/immunology , HIV Infections/cerebrospinal fluid , HIV Infections/complications
2.
Science ; 385(6705): 174-178, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38991083

ABSTRACT

One of the hallmarks of living organisms is their capacity for self-organization and regeneration, which requires a tight integration of metabolic and genetic networks. We sought to construct a linked metabolic and genetic network in vitro that shows such lifelike behavior outside of a cellular context and generates its own building blocks from nonliving matter. We integrated the metabolism of the crotonyl-CoA/ethyl-malonyl-CoA/hydroxybutyryl-CoA cycle with cell-free protein synthesis using recombinant elements. Our network produces the amino acid glycine from CO2 and incorporates it into target proteins following DNA-encoded instructions. By orchestrating ~50 enzymes we established a basic cell-free operating system in which genetically encoded inputs into a metabolic network are programmed to activate feedback loops allowing for self-integration and (partial) self-regeneration of the complete system.


Subject(s)
Cell-Free System , Metabolic Networks and Pathways , Protein Biosynthesis , Glycine/metabolism , Gene Regulatory Networks , Escherichia coli/metabolism , Escherichia coli/genetics , Carbon Dioxide/metabolism , Acyl Coenzyme A/metabolism , Feedback, Physiological
3.
Neurol Neuroimmunol Neuroinflamm ; 11(5): e200281, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38991170

ABSTRACT

BACKGROUND AND OBJECTIVES: Progressive multifocal leukoencephalopathy (PML) is a severe neurologic disease resulting from JC virus reactivation in immunocompromised patients. Certain multiple sclerosis (MS) disease-modifying therapies (DMTs) are associated with PML risk, such as natalizumab and, more rarely, sphingosine-1-phosphate receptor modulators (S1P-RMs). Although natalizumab-associated PML is well documented, information on S1P-RM-associated PML is limited. The aim of this study is to compare clinical presentations and outcomes between the 2 groups. METHODS: A retrospective multicenter cohort study included patients with PML from 2009 to 2022 treated with S1P-RMs or natalizumab. Data on clinical and radiologic presentation, outcomes, immune reconstitution inflammatory syndrome (IRIS), survival, disability (using the modified Ranking scale-mRS), and MS relapses post-PML were analyzed. RESULTS: Of 88 patients, 84 were analyzed (20 S1P-RM, 64 natalizumab). S1P-RM-associated PML was diagnosed in older patients (median age 52 vs 44 years, p < 0.001) and after longer treatment duration (median 63.9 vs 40 months, p < 0.001). Similarly, S1P-RM patients were more prone to show symptoms at diagnosis (100 vs 80.6%, p = 0.035), had more disseminated lesions (80% vs 34.9%, p = 0.002), and had higher gadolinium enhancement (65% vs 39.1%, p = 0.042). Natalizumab patients had a higher IRIS development rate (OR: 8.3 [1.92-33.3]). Overall, the outcome (mRS) at 12 months was similar in the 2 groups (OR: 0.81 [0.32-2.0]). Yet, post-treatment MS activity was higher in S1P-RM cases (OR: 5.7 [1.4-22.2]). DISCUSSION: S1P-RM-associated PML shows reduced IRIS risk but higher post-treatment MS activity. Clinicians should tailor post-PML treatment based on pre-PML medication.


Subject(s)
Leukoencephalopathy, Progressive Multifocal , Natalizumab , Sphingosine 1 Phosphate Receptor Modulators , Humans , Leukoencephalopathy, Progressive Multifocal/chemically induced , Natalizumab/adverse effects , Male , Middle Aged , Female , Adult , Retrospective Studies , Sphingosine 1 Phosphate Receptor Modulators/pharmacology , Sphingosine 1 Phosphate Receptor Modulators/adverse effects , Multiple Sclerosis/drug therapy , Immunologic Factors/adverse effects , Immunologic Factors/pharmacology , Immunologic Factors/administration & dosage , Cohort Studies , Aged , Immune Reconstitution Inflammatory Syndrome/chemically induced
4.
mBio ; : e0152424, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38953632

ABSTRACT

The hydroxyacid glycolate is a highly abundant carbon source in the environment. Glycolate is produced by unicellular photosynthetic organisms and excreted at petagram scales to the environment, where it serves as growth substrate for heterotrophic bacteria. In microbial metabolism, glycolate is first oxidized to glyoxylate by the enzyme glycolate oxidase. The recently described ß-hydroxyaspartate cycle (BHAC) subsequently mediates the carbon-neutral assimilation of glyoxylate into central metabolism in ubiquitous Alpha- and Gammaproteobacteria. Although the reaction sequence of the BHAC was elucidated in Paracoccus denitrificans, little is known about the regulation of glycolate and glyoxylate assimilation in this relevant alphaproteobacterial model organism. Here, we show that regulation of glycolate metabolism in P. denitrificans is surprisingly complex, involving two regulators, the IclR-type transcription factor BhcR that acts as an activator for the BHAC gene cluster, and the GntR-type transcriptional regulator GlcR, a previously unidentified repressor that controls the production of glycolate oxidase. Furthermore, an additional layer of regulation is exerted at the global level, which involves the transcriptional regulator CceR that controls the switch between glycolysis and gluconeogenesis in P. denitrificans. Together, these regulators control glycolate metabolism in P. denitrificans, allowing the organism to assimilate glycolate together with other carbon substrates in a simultaneous fashion, rather than sequentially. Our results show that the metabolic network of Alphaproteobacteria shows a high degree of flexibility to react to the availability of multiple substrates in the environment.IMPORTANCEAlgae perform ca. 50% of the photosynthetic carbon dioxide fixation on our planet. In the process, they release the two-carbon molecule glycolate. Due to the abundance of algae, massive amounts of glycolate are released. Therefore, this molecule is available as a source of carbon for bacteria in the environment. Here, we describe the regulation of glycolate metabolism in the model organism Paracoccus denitrificans. This bacterium uses the recently characterized ß-hydroxyaspartate cycle to assimilate glycolate in a carbon- and energy-efficient manner. We found that glycolate assimilation is dynamically controlled by three different transcriptional regulators: GlcR, BhcR, and CceR. This allows P. denitrificans to assimilate glycolate together with other carbon substrates in a simultaneous fashion. Overall, this flexible and multi-layered regulation of glycolate metabolism in P. denitrificans represents a resource-efficient strategy to make optimal use of this globally abundant molecule under fluctuating environmental conditions.

5.
BMC Pediatr ; 24(1): 315, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714956

ABSTRACT

BACKGROUND: Ultrasound (US) is often the first method used to look for brain or cerebrospinal fluid (CSF) space pathologies. Knowledge of normal CSF width values is essential. Most of the available US normative values were established over 20 years ago, were obtained with older equipment, and cover only part of the age spectrum that can be examined by cranial US. This prospective study aimed to determine the normative values of the widths of the subarachnoid and internal CSF spaces (craniocortical, minimal and maximal interhemispheric, interventricular, and frontal horn) for high-resolution linear US probes in neurologically healthy infants and children aged 0-19 months and assess whether subdural fluid collections can be delineated. METHODS: Two radiologists measured the width of the CSF spaces with a conventional linear probe and an ultralight hockey-stick probe in neurologically healthy children not referred for cranial or spinal US. RESULTS: This study included 359 neurologically healthy children (nboys = 178, 49.6%; ngirls = 181, 50.4%) with a median age of 46.0 days and a range of 1-599 days. We constructed prediction plots, including the 5th, 50th, and 95th percentiles, and an interactive spreadsheet to calculate normative values for individual patients. The measurements of the two probes and the left and right sides did not differ, eliminating the need for separate normative values. No subdural fluid collection was detected. CONCLUSION: Normative values for the widths of the subarachnoid space and the internal CSF spaces are useful for evaluating intracranial pathology, especially when determining whether an increase in the subarachnoid space width is abnormal.


Subject(s)
Subarachnoid Space , Ultrasonography , Humans , Infant , Prospective Studies , Male , Female , Reference Values , Infant, Newborn , Ultrasonography/methods , Subarachnoid Space/diagnostic imaging , Cerebrospinal Fluid/diagnostic imaging
7.
Cell Oncol (Dordr) ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38805131

ABSTRACT

PURPOSE: Pancreatic Ductal Adenocarcinoma (PDAC) remains a challenging disease due to its complex biology and aggressive behavior with an urgent need for efficient therapeutic strategies. To assess therapy response, pre-clinical PDAC organoid-based models in combination with accurate real-time monitoring are required. METHODS: We established stable live-imaging organoid/peripheral blood mononuclear cells (PBMCs) co-cultures and introduced OrganoIDNet, a deep-learning-based algorithm, capable of analyzing bright-field images of murine and human patient-derived PDAC organoids acquired with live-cell imaging. We investigated the response to the chemotherapy gemcitabine in PDAC organoids and the PD-L1 inhibitor Atezolizumab, cultured with or without HLA-matched PBMCs over time. Results obtained with OrganoIDNet were validated with the endpoint proliferation assay CellTiter-Glo. RESULTS: Live cell imaging in combination with OrganoIDNet accurately detected size-specific drug responses of organoids to gemcitabine over time, showing that large organoids were more prone to cytotoxic effects. This approach also allowed distinguishing between healthy and unhealthy status and measuring eccentricity as organoids' reaction to therapy. Furthermore, imaging of a new organoids/PBMCs sandwich-based co-culture enabled longitudinal analysis of organoid responses to Atezolizumab, showing an increased potency of PBMCs tumor-killing in an organoid-individual manner when Atezolizumab was added. CONCLUSION: Optimized PDAC organoid imaging analyzed by OrganoIDNet represents a platform capable of accurately detecting organoid responses to standard PDAC chemotherapy over time. Moreover, organoid/immune cell co-cultures allow monitoring of organoid responses to immunotherapy, offering dynamic insights into treatment behavior within a co-culture setting with PBMCs. This setup holds promise for real-time assessment of immunotherapeutic effects in individual patient-derived PDAC organoids.

8.
Nature ; 629(8013): 784-790, 2024 May.
Article in English | MEDLINE | ID: mdl-38720075

ABSTRACT

Electro-optical photonic integrated circuits (PICs) based on lithium niobate (LiNbO3) have demonstrated the vast capabilities of materials with a high Pockels coefficient1,2. They enable linear and high-speed modulators operating at complementary metal-oxide-semiconductor voltage levels3 to be used in applications including data-centre communications4, high-performance computing and photonic accelerators for AI5. However, industrial use of this technology is hindered by the high cost per wafer and the limited wafer size. The high cost results from the lack of existing high-volume applications in other domains of the sort that accelerated the adoption of silicon-on-insulator (SOI) photonics, which was driven by vast investment in microelectronics. Here we report low-loss PICs made of lithium tantalate (LiTaO3), a material that has already been adopted commercially for 5G radiofrequency filters6 and therefore enables scalable manufacturing at low cost, and it has equal, and in some cases superior, properties to LiNbO3. We show that LiTaO3 can be etched to create low-loss (5.6 dB m-1) PICs using a deep ultraviolet (DUV) stepper-based manufacturing process7. We demonstrate a LiTaO3 Mach-Zehnder modulator (MZM) with a half-wave voltage-length product of 1.9 V cm and an electro-optic bandwidth of up to 40 GHz. In comparison with LiNbO3, LiTaO3 exhibits a much lower birefringence, enabling high-density circuits and broadband operation over all telecommunication bands. Moreover, the platform supports the generation of soliton microcombs. Our work paves the way for the scalable manufacture of low-cost and large-volume next-generation electro-optical PICs.

10.
Nat Commun ; 15(1): 3950, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38729959

ABSTRACT

Superconducting qubits are among the most advanced candidates for achieving fault-tolerant quantum computing. Despite recent significant advancements in the qubit lifetimes, the origin of the loss mechanism for state-of-the-art qubits is still subject to investigation. Furthermore, the successful implementation of quantum error correction requires negligible correlated errors between qubits. Here, we realize long-lived superconducting transmon qubits that exhibit fluctuating lifetimes, averaging 0.2 ms and exceeding 0.4 ms - corresponding to quality factors above 5 million and 10 million, respectively. We then investigate their dominant error mechanism. By introducing novel time-resolved error measurements that are synchronized with the operation of the pulse tube cooler in a dilution refrigerator, we find that mechanical vibrations from the pulse tube induce nonequilibrium dynamics in highly coherent qubits, leading to their correlated bit-flip errors. Our findings not only deepen our understanding of the qubit error mechanisms but also provide valuable insights into potential error-mitigation strategies for achieving fault tolerance by decoupling superconducting qubits from their mechanical environments.

11.
Nat Commun ; 15(1): 3134, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605067

ABSTRACT

Chip-scale integration is a key enabler for the deployment of photonic technologies. Coherent laser ranging or FMCW LiDAR, a perception technology that benefits from instantaneous velocity and distance detection, eye-safe operation, long-range, and immunity to interference. However, wafer-scale integration of these systems has been challenged by stringent requirements on laser coherence, frequency agility, and the necessity for optical amplifiers. Here, we demonstrate a photonic-electronic LiDAR source composed of a micro-electronic-based high-voltage arbitrary waveform generator, a hybrid photonic circuit-based tunable Vernier laser with piezoelectric actuators, and an erbium-doped waveguide amplifier. Importantly, all systems are realized in a wafer-scale manufacturing-compatible process comprising III-V semiconductors, silicon nitride photonic integrated circuits, and 130-nm SiGe bipolar complementary metal-oxide-semiconductor (CMOS) technology. We conducted ranging experiments at a 10-meter distance with a precision level of 10 cm and a 50 kHz acquisition rate. The laser source is turnkey and linearization-free, and it can be seamlessly integrated with existing focal plane and optical phased array LiDAR approaches.

12.
Cardiovasc Intervent Radiol ; 47(5): 621-631, 2024 May.
Article in English | MEDLINE | ID: mdl-38639781

ABSTRACT

PURPOSE: CT-guided percutaneous core biopsy of the lung is usually performed under local anesthesia, but can also be conducted under additional systemic opioid medication. The purpose of this retrospective study was to assess the effect of intravenous piritramide application on the pneumothorax rate and to identify risk factors for post-biopsy pneumothorax. MATERIALS AND METHODS: One hundred and seventy-one core biopsies of the lung were included in this retrospective single center study. The incidence of pneumothorax and chest tube placement was evaluated. Patient-, procedure- and target-related variables were analyzed by univariate and multivariable logistic regression analysis. RESULTS: The overall incidence of pneumothorax was 39.2% (67/171). The pneumothorax rate was 31.5% (29/92) in patients who received intravenous piritramide and 48.1% (38/79) in patients who did not receive piritramide. In multivariable logistic regression analysis periinterventional piritramide application proved to be the only independent factor to reduce the risk of pneumothorax (odds ratio 0.46, 95%-confidence interval 0.24, 0.88; p = 0.018). Two or more pleura passages (odds ratio 3.38, 95%-confidence interval: 1.15, 9.87; p = 0.026) and prone position of the patient (odds ratio 2.27, 95%-confidence interval: 1.04, 4.94; p = 0.039) were independent risk factors for a higher pneumothorax rate. CONCLUSION: Procedural opioid medication with piritramide proved to be a previously undisclosed factor decreasing the risk of pneumothorax associated with CT-guided percutaneous core biopsy of the lung. LEVEL OF EVIDENCE 4: small study cohort.


Subject(s)
Analgesics, Opioid , Image-Guided Biopsy , Lung , Pirinitramide , Pneumothorax , Radiography, Interventional , Tomography, X-Ray Computed , Humans , Pneumothorax/prevention & control , Pneumothorax/etiology , Female , Male , Retrospective Studies , Tomography, X-Ray Computed/methods , Middle Aged , Analgesics, Opioid/administration & dosage , Radiography, Interventional/methods , Aged , Image-Guided Biopsy/adverse effects , Image-Guided Biopsy/methods , Risk Factors , Lung/diagnostic imaging , Lung/pathology , Pirinitramide/administration & dosage , Pirinitramide/therapeutic use , Adult , Incidence
13.
Nature ; 628(8009): 894-900, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38600380

ABSTRACT

Fractals are patterns that are self-similar across multiple length-scales1. Macroscopic fractals are common in nature2-4; however, so far, molecular assembly into fractals is restricted to synthetic systems5-12. Here we report the discovery of a natural protein, citrate synthase from the cyanobacterium Synechococcus elongatus, which self-assembles into Sierpinski triangles. Using cryo-electron microscopy, we reveal how the fractal assembles from a hexameric building block. Although different stimuli modulate the formation of fractal complexes and these complexes can regulate the enzymatic activity of citrate synthase in vitro, the fractal may not serve a physiological function in vivo. We use ancestral sequence reconstruction to retrace how the citrate synthase fractal evolved from non-fractal precursors, and the results suggest it may have emerged as a harmless evolutionary accident. Our findings expand the space of possible protein complexes and demonstrate that intricate and regulatable assemblies can evolve in a single substitution.


Subject(s)
Citrate (si)-Synthase , Evolution, Molecular , Fractals , Protein Multimerization , Synechococcus , Cryoelectron Microscopy , Models, Molecular , Synechococcus/enzymology , Citrate (si)-Synthase/chemistry , Citrate (si)-Synthase/metabolism , Citrate (si)-Synthase/ultrastructure
14.
Nutr Metab Cardiovasc Dis ; 34(7): 1670-1680, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38664125

ABSTRACT

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is the most common cause of death in Europe. Although the 2019 European Society of Cardiology/European Atherosclerosis Society Guidelines for the management of dyslipidaemias claim a target low-density lipoprotein cholesterol (LDL-C) value of <55 mg/dL for very high-risk patients by use of lipid-lowering therapy (LLT) and lifestyle adaptations, the target level achievement is not satisfactory. We examined LLT use in ASCVD patients exceeding LDL-C target levels at admission and its adaptations at discharge. METHODS AND RESULTS: Between January 2017 and February 2020, 1091 patients with LDL-C >100 mg/dL and ASCVD defined as diagnosis of angina pectoris (AP, n = 179), acute myocardial infarction (AMI, n = 317), chronic ischemic heart disease (CHD, n = 195), or peripheral artery disease (PAD, n = 400) were extracted from hospital records. LLT use on admission and discharge as well as recommendations on lifestyle and nutrition were analysed. On admission, 51% of the patients were not taking LLT. At discharge, 91% were prescribed statins and 87% were advised on lifestyle adaptation and/or pharmacological treatment. High-intensity statin use at discharge was present in 63% of the AP-group, 92% of the AMI-group, 62% of the CHD-group and 71% of the PAD-group. Ezetimibe was present in 16% and proprotein convertase subtilisin/kexin 9 inhibitors (PCSK9i) in 1%. However, of those on high-intensity statin, 25% remained on insufficient statin dosage. CONCLUSION: Switch to high-intensity statins and use of ezetimibe and PCSK9i was low in chronic ASCVD patients. Even though statin intake was high in high-risk patients, target levels were still not reached.


Subject(s)
Atherosclerosis , Biomarkers , Cholesterol, LDL , Dyslipidemias , Humans , Male , Female , Retrospective Studies , Aged , Middle Aged , Dyslipidemias/drug therapy , Dyslipidemias/blood , Dyslipidemias/diagnosis , Dyslipidemias/epidemiology , Biomarkers/blood , Cholesterol, LDL/blood , Risk Assessment , Atherosclerosis/blood , Atherosclerosis/diagnosis , Atherosclerosis/drug therapy , Atherosclerosis/epidemiology , Atherosclerosis/prevention & control , Treatment Outcome , Time Factors , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Heart Disease Risk Factors , Patient Discharge , Patient Admission , Risk Reduction Behavior , PCSK9 Inhibitors , Risk Factors , Hypolipidemic Agents/therapeutic use , Aged, 80 and over , Practice Patterns, Physicians' , Proprotein Convertase 9
15.
Circulation ; 149(20): 1549-1564, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38606558

ABSTRACT

BACKGROUND: Among patients with pulmonary arterial hypertension (PAH), acute vasoreactivity testing during right heart catheterization may identify acute vasoresponders, for whom treatment with high-dose calcium channel blockers (CCBs) is recommended. However, long-term outcomes in the current era remain largely unknown. We sought to evaluate the implications of acute vasoreactivity response for long-term response to CCBs and other outcomes. METHODS: Patients diagnosed with PAH between January 1999 and December 2018 at 15 pulmonary hypertension centers were included and analyzed retrospectively. In accordance with current guidelines, acute vasoreactivity response was defined by a decrease of mean pulmonary artery pressure by ≥10 mm Hg to reach <40 mm Hg, without a decrease in cardiac output. Long-term response to CCBs was defined as alive with unchanged initial CCB therapy with or without other initial PAH therapy and World Health Organization functional class I/II and/or low European Society of Cardiology/European Respiratory Society risk status at 12 months after initiation of CCBs. Patients were followed for up to 5 years; clinical measures, outcome, and subsequent treatment patterns were captured. RESULTS: Of 3702 patients undergoing right heart catheterization for PAH diagnosis, 2051 had idiopathic, heritable, or drug-induced PAH, of whom 1904 (92.8%) underwent acute vasoreactivity testing. A total of 162 patients fulfilled acute vasoreactivity response criteria and received an initial CCB alone (n=123) or in combination with another PAH therapy (n=39). The median follow-up time was 60.0 months (interquartile range, 30.8-60.0), during which overall survival was 86.7%. At 12 months, 53.2% remained on CCB monotherapy, 14.7% on initial CCB plus another initial PAH therapy, and the remaining patients had the CCB withdrawn and/or PAH therapy added. CCB long-term response was found in 54.3% of patients. Five-year survival was 98.5% in long-term responders versus 73.0% in nonresponders. In addition to established vasodilator responder criteria, pulmonary artery compliance at acute vasoreactivity testing, low risk status and NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels at early follow-up correlated with long-term response and predicted survival. CONCLUSIONS: Our data display heterogeneity within the group of vasoresponders, with a large subset failing to show a sustained satisfactory clinical response to CCBs. This highlights the necessity for comprehensive reassessment during early follow-up. The use of pulmonary artery compliance in addition to current measures may better identify those likely to have a good long-term response.


Subject(s)
Calcium Channel Blockers , Cardiac Catheterization , Pulmonary Arterial Hypertension , Humans , Female , Male , Middle Aged , Retrospective Studies , Pulmonary Arterial Hypertension/drug therapy , Pulmonary Arterial Hypertension/physiopathology , Pulmonary Arterial Hypertension/diagnosis , Pulmonary Arterial Hypertension/mortality , Treatment Outcome , Calcium Channel Blockers/therapeutic use , Pulmonary Artery/physiopathology , Pulmonary Artery/drug effects , Adult , Aged , Antihypertensive Agents/therapeutic use
16.
Chem Sci ; 15(13): 4960-4968, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38550681

ABSTRACT

The conversion of CO2 by enzymes such as carbonic anhydrase or carboxylases plays a crucial role in many biological processes. However, in situ methods following the microscopic details of CO2 conversion at the active site are limited. Here, we used infrared spectroscopy to study the interaction of CO2, water, bicarbonate, and other reactants with ß-carbonic anhydrase from Escherichia coli (EcCA) and crotonyl-CoA carboxylase/reductase from Kitasatospora setae (KsCcr), two of the fastest CO2-converting enzymes in nature. Our data reveal that KsCcr possesses a so far unknown metal-independent CA-like activity. Site-directed mutagenesis of conserved active site residues combined with molecular dynamics simulations tracing CO2 distributions in the active site of KsCCr identify an 'activated' water molecule forming the hydroxyl anion that attacks CO2 and yields bicarbonate (HCO3-). Computer simulations also explain why substrate binding inhibits the anhydrase activity. Altogether, we demonstrate how in situ infrared spectroscopy combined with molecular dynamics simulations provides a simple yet powerful new approach to investigate the atomistic reaction mechanisms of different enzymes with CO2.

17.
Hepatol Res ; 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38509789

ABSTRACT

AIM: Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease characterized by inflammation of the intra- and extrahepatic bile ducts. Pathogenesis of PSC is still enigmatic but is likely to be multifactorial. Recently, we identified an interleukin-6 (IL-6)-dependent signal transducer and activator of transcription 3 (STAT3) activation in CD4+ TH1 and TH17 cells in PSC. The IL-6/STAT3 pathway was shown to be regulated by protease-activated receptor 1 (PAR1) contributing to inflammation. The role of the PAR1 -506 deletion/insertion (Del/Ins) polymorphism in PSC has not yet been investigated. METHODS: Two hundred eighty four PSC patients (200 patients with inflammatory bowel diseases [IBD] and 84 without IBD) and 309 healthy controls were genotyped for PAR1 rs11267092 (-506 Del/Ins -13 bp). Results were correlated with clinical characteristics and transplant-free survival. RESULTS: The frequency of PAR1 -506 Ins allele carriers (Del/Ins and Ins/Ins) was significantly higher in PSC patients (57.0%) compared to healthy controls (39.8%). Furthermore, carriers of PAR1 -506 Ins allele were more likely to have PSC than noncarriers (odds ratio 2.01; 95% confidence interval, 1.45-2.79). Patients with PSC carrying the PAR1 -506 Ins allele showed significantly higher alanine aminotransferase serum levels (p = 0.0357) and a trend toward shorter transplant-free survival time compared to noncarriers (8.9 ± 6.6 years vs. 10.5 ± 7.1 years; p = 0.076). CONCLUSIONS: Our study shows that PAR1 -506 Ins is significantly more frequent in people with PSC. As PAR1 -506 Ins allele carriers tended to have a shorter transplant-free survival, PAR1 might play a role in the development and course of PSC.

18.
Inn Med (Heidelb) ; 65(4): 357-364, 2024 Apr.
Article in German | MEDLINE | ID: mdl-38446182

ABSTRACT

BACKGROUND: Despite substantial progress in the management of viral and autoimmune liver diseases, these entities remain relevant indications for liver transplantation. AIMS: To provide an overview of the current knowledge regarding the management of viral and autoimmune liver diseases before and after liver transplantation. MATERIALS AND METHODS: Selective literature search, including current guidelines and abstracts of key scientific meetings. RESULTS AND DISCUSSION: Viral and autoimmune liver disease can be effectively treated in most cases, which has resulted in an overall decline in liver transplantations for this indication group. However, hepatitis D infection and primary sclerosing cholangitis remain difficult-to-treat liver diseases in some patients and may progress to end-stage liver disease despite best possible management. Viral or autoimmune hepatitis can lead to fulminant liver failure requiring emergency liver transplantation. In patients who are transplanted due to viral or autoimmune liver disease, specific measures to prevent recurrence of these diseases after transplantation are mandatory. In view of effective treatment modalities for chronic hepatitis B and C, even liver grafts from donors infected with these viruses can be considered for liver transplantation under certain circumstances.


Subject(s)
Cholangitis, Sclerosing , Liver Cirrhosis, Biliary , Liver Transplantation , Humans , Cholangitis, Sclerosing/surgery , Recurrence
19.
Nature ; 629(8010): 53-57, 2024 May.
Article in English | MEDLINE | ID: mdl-38447669

ABSTRACT

Local and low-redshift (z < 3) galaxies are known to broadly follow a bimodal distribution: actively star-forming galaxies with relatively stable star-formation rates and passive systems. These two populations are connected by galaxies in relatively slow transition. By contrast, theory predicts that star formation was stochastic at early cosmic times and in low-mass systems1-4. These galaxies transitioned rapidly between starburst episodes and phases of suppressed star formation, potentially even causing temporary quiescence-so-called mini-quenching events5,6. However, the regime of star-formation burstiness is observationally highly unconstrained. Directly observing mini-quenched galaxies in the primordial Universe is therefore of utmost importance to constrain models of galaxy formation and transformation7,8. Early quenched galaxies have been identified out to redshift z < 5 (refs. 9-12) and these are all found to be massive (M⋆ > 1010 M⊙) and relatively old. Here we report a (mini-)quenched galaxy at z = 7.3, when the Universe was only 700 Myr old. The JWST/NIRSpec spectrum is very blue (U-V = 0.16 ± 0.03 mag) but exhibits a Balmer break and no nebular emission lines. The galaxy experienced a short starburst followed by rapid quenching; its stellar mass (4-6 × 108 M⊙) falls in a range that is sensitive to various feedback mechanisms, which can result in perhaps only temporary quenching.


Subject(s)
Galaxies , Time Factors , Stars, Celestial , Extraterrestrial Environment/chemistry
20.
Sensors (Basel) ; 24(5)2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38474990

ABSTRACT

The modeling and forecasting of cerebral pressure-flow dynamics in the time-frequency domain have promising implications for veterinary and human life sciences research, enhancing clinical care by predicting cerebral blood flow (CBF)/perfusion, nutrient delivery, and intracranial pressure (ICP)/compliance behavior in advance. Despite its potential, the literature lacks coherence regarding the optimal model type, structure, data streams, and performance. This systematic scoping review comprehensively examines the current landscape of cerebral physiological time-series modeling and forecasting. It focuses on temporally resolved cerebral pressure-flow and oxygen delivery data streams obtained from invasive/non-invasive cerebral sensors. A thorough search of databases identified 88 studies for evaluation, covering diverse cerebral physiologic signals from healthy volunteers, patients with various conditions, and animal subjects. Methodologies range from traditional statistical time-series analysis to innovative machine learning algorithms. A total of 30 studies in healthy cohorts and 23 studies in patient cohorts with traumatic brain injury (TBI) concentrated on modeling CBFv and predicting ICP, respectively. Animal studies exclusively analyzed CBF/CBFv. Of the 88 studies, 65 predominantly used traditional statistical time-series analysis, with transfer function analysis (TFA), wavelet analysis, and autoregressive (AR) models being prominent. Among machine learning algorithms, support vector machine (SVM) was widely utilized, and decision trees showed promise, especially in ICP prediction. Nonlinear models and multi-input models were prevalent, emphasizing the significance of multivariate modeling and forecasting. This review clarifies knowledge gaps and sets the stage for future research to advance cerebral physiologic signal analysis, benefiting neurocritical care applications.


Subject(s)
Brain Injuries, Traumatic , Animals , Humans
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