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1.
Nucleic Acids Res ; 52(17): 10144-10160, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39175109

RESUMEN

Most heritable diseases are polygenic. To comprehend the underlying genetic architecture, it is crucial to discover the clinically relevant epistatic interactions (EIs) between genomic single nucleotide polymorphisms (SNPs) (1-3). Existing statistical computational methods for EI detection are mostly limited to pairs of SNPs due to the combinatorial explosion of higher-order EIs. With NeEDL (network-based epistasis detection via local search), we leverage network medicine to inform the selection of EIs that are an order of magnitude more statistically significant compared to existing tools and consist, on average, of five SNPs. We further show that this computationally demanding task can be substantially accelerated once quantum computing hardware becomes available. We apply NeEDL to eight different diseases and discover genes (affected by EIs of SNPs) that are partly known to affect the disease, additionally, these results are reproducible across independent cohorts. EIs for these eight diseases can be interactively explored in the Epistasis Disease Atlas (https://epistasis-disease-atlas.com). In summary, NeEDL demonstrates the potential of seamlessly integrated quantum computing techniques to accelerate biomedical research. Our network medicine approach detects higher-order EIs with unprecedented statistical and biological evidence, yielding unique insights into polygenic diseases and providing a basis for the development of improved risk scores and combination therapies.


Asunto(s)
Epistasis Genética , Polimorfismo de Nucleótido Simple , Humanos , Teoría Cuántica , Herencia Multifactorial/genética , Enfermedad/genética , Biología Computacional/métodos , Algoritmos , Predisposición Genética a la Enfermedad
2.
J Cell Sci ; 136(24)2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38149872

RESUMEN

Liquid-liquid phase separation is a major mechanism for organizing macromolecules, particularly proteins with intrinsically disordered regions, in compartments not limited by a membrane or a scaffold. The cell can therefore be perceived as a complex emulsion containing many of these membraneless organelles, also referred to as biomolecular condensates, together with numerous membrane-bound organelles. It is currently unclear how such a complex concoction operates to allow for intracellular trafficking, signaling and metabolic processes to occur with high spatiotemporal precision. Based on experimental observations of synaptic vesicle condensates - a membraneless organelle that is in fact packed with membranes - we present here the framework of dipping contacts: a novel type of contact site between membraneless organelles and membranes. In this Hypothesis, we propose that our framework of dipping contacts can serve as a foundation to investigate the interface that couples the diffusion and material properties of condensates to biochemical processes occurring in membranes. The identity and regulation of this interface is especially critical in the case of neurodegenerative diseases, where aberrant inclusions of misfolded proteins and damaged organelles underlie cellular pathology.


Asunto(s)
Condensados Biomoleculares , Orgánulos , Orgánulos/metabolismo , Proteínas/metabolismo , Membranas , Membranas Mitocondriales
3.
N Engl J Med ; 387(8): 679-691, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-35866746

RESUMEN

BACKGROUND: Before April 2022, monkeypox virus infection in humans was seldom reported outside African regions where it is endemic. Currently, cases are occurring worldwide. Transmission, risk factors, clinical presentation, and outcomes of infection are poorly defined. METHODS: We formed an international collaborative group of clinicians who contributed to an international case series to describe the presentation, clinical course, and outcomes of polymerase-chain-reaction-confirmed monkeypox virus infections. RESULTS: We report 528 infections diagnosed between April 27 and June 24, 2022, at 43 sites in 16 countries. Overall, 98% of the persons with infection were gay or bisexual men, 75% were White, and 41% had human immunodeficiency virus infection; the median age was 38 years. Transmission was suspected to have occurred through sexual activity in 95% of the persons with infection. In this case series, 95% of the persons presented with a rash (with 64% having ≤10 lesions), 73% had anogenital lesions, and 41% had mucosal lesions (with 54 having a single genital lesion). Common systemic features preceding the rash included fever (62%), lethargy (41%), myalgia (31%), and headache (27%); lymphadenopathy was also common (reported in 56%). Concomitant sexually transmitted infections were reported in 109 of 377 persons (29%) who were tested. Among the 23 persons with a clear exposure history, the median incubation period was 7 days (range, 3 to 20). Monkeypox virus DNA was detected in 29 of the 32 persons in whom seminal fluid was analyzed. Antiviral treatment was given to 5% of the persons overall, and 70 (13%) were hospitalized; the reasons for hospitalization were pain management, mostly for severe anorectal pain (21 persons); soft-tissue superinfection (18); pharyngitis limiting oral intake (5); eye lesions (2); acute kidney injury (2); myocarditis (2); and infection-control purposes (13). No deaths were reported. CONCLUSIONS: In this case series, monkeypox manifested with a variety of dermatologic and systemic clinical findings. The simultaneous identification of cases outside areas where monkeypox has traditionally been endemic highlights the need for rapid identification and diagnosis of cases to contain further community spread.


Asunto(s)
Salud Global , Mpox , Adulto , Exantema/etiología , Femenino , Fiebre/etiología , Salud Global/estadística & datos numéricos , Humanos , Masculino , Mpox/epidemiología , Mpox/terapia , Monkeypox virus
4.
PLoS Pathog ; 19(11): e1011841, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38033163

RESUMEN

Macrophages play a key role in disseminated cryptococcosis, a deadly fungal disease caused by Cryptococcus neoformans. This opportunistic infection can arise following the reactivation of a poorly characterized latent infection attributed to dormant C. neoformans. Here, we investigated the mechanisms underlying reactivation of dormant C. neoformans using an in vitro co-culture model of viable but non-culturable (VBNC; equivalent of dormant) yeast cells with bone marrow-derived murine macrophages (BMDMs). Comparative transcriptome analysis of BMDMs incubated with log, stationary phase or VBNC cells of C. neoformans showed that VBNC cells elicited a reduced transcriptional modification of the macrophage but retaining the ability to regulate genes important for immune response, such as NLRP3 inflammasome-related genes. We further confirmed the maintenance of the low immunostimulatory capacity of VBNC cells using multiplex cytokine profiling, and analysis of cell wall composition and dectin-1 ligands exposure. In addition, we evaluated the effects of classic (M1) or alternative (M2) macrophage polarization on VBNC cells. We observed that intracellular residence sustained dormancy, regardless of the polarization state of macrophages and despite indirect detection of pantothenic acid (or its derivatives), a known reactivator for VBNC cells, in the C. neoformans-containing phagolysosome. Notably, M0 and M2, but not M1 macrophages, induced extracellular reactivation of VBNC cells by the secretion of extracellular vesicles and non-lytic exocytosis. Our results indicate that VBNC cells retain the low immunostimulatory profile required for persistence of C. neoformans in the host. We also describe a pro-pathogen role of macrophage-derived extracellular vesicles in C. neoformans infection and reinforce the impact of non-lytic exocytosis and the macrophage profile on the pathophysiology of cryptococcosis.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Vesículas Extracelulares , Animales , Ratones , Cryptococcus neoformans/genética , Criptococosis/microbiología , Macrófagos , Exocitosis
5.
J Infect Dis ; 229(6): 1781-1785, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38385222

RESUMEN

Human immunodeficiency virus type 1 (HIV-1) disease manifestations differ between cisgender women and men, including better control of viral replication during primary infection and less frequent residual HIV-1 replication on antiretroviral therapy (ART) in cisgender women with HIV-1 (WWH). Investigating plasmacytoid dendritic cell (pDC) functions and HIV-1 reservoir sizes in 20 WWH on stable ART, we observed inverse correlations between interferon-α and tumor necrosis factor responses of pDCs to Toll-like receptor 7/8 stimulation and intact/total proviral HIV-1 DNA levels. Additionally, ISG15 mRNA levels in peripheral blood mononuclear cells correlated with cytokine responses of pDCs. These findings demonstrate an association between higher type I interferon responses and lower HIV-1 reservoir sizes in WWH on ART, warranting studies to identify the underlying mechanisms.


Asunto(s)
Células Dendríticas , Infecciones por VIH , VIH-1 , Interferón Tipo I , Receptor Toll-Like 7 , Humanos , Células Dendríticas/inmunología , Células Dendríticas/virología , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Adulto , Persona de Mediana Edad , Replicación Viral/efectos de los fármacos , Carga Viral , Antirretrovirales/uso terapéutico , Leucocitos Mononucleares/virología , Leucocitos Mononucleares/inmunología
6.
Int J Med Microbiol ; 314: 151614, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38368645

RESUMEN

Cryptococcosis is the most prevalent fungal infection of the central nervous system worldwide. We performed a retrospective multicenter cohort study to gain insights into the epidemiology of cryptococcosis in Germany. We describe the use of diagnostic tests, clinical management and patient outcome. We included 64 patients with underlying HIV infection (55%) or other predispositions. Molecular typing by MLST documented 20 individual sequence types among 42 typed isolates. A fatal outcome was documented in 14% of patients in the first two months after diagnosis.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Infecciones por VIH , Humanos , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Tipificación de Secuencias Multilocus , Estudios de Cohortes , Criptococosis/diagnóstico , Criptococosis/epidemiología , Criptococosis/microbiología , Alemania/epidemiología , Estudios Retrospectivos
7.
Eur Radiol ; 34(11): 7104-7114, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38713278

RESUMEN

OBJECTIVES: Neonatal MRI is usually performed under deep sedation, which is challenging-especially in low-weight premature patients. In addition, long-term side effects, such as neurotoxicity, are of concern. An alternative to sedation is to induce natural sleep by feeding and immobilising the child, the "feed-and-wrap" technique (FWT). The objective of this study was to evaluate differences in image quality between neonates examined under sedation and by using the FWT during the first four months of life. MATERIALS AND METHODS: We retrospectively assessed image quality (based on a 4-point semiquantitative scale) of all MRI examinations in neonates performed at our institution between July 2009 and August 2022. Differences in image quality between examinations under sedation versus FWT were evaluated. RESULTS: We included 432 consecutive patients, 243 (56%) using sedation and 189 (44%) using the FWT. Corrected age and body weight (mean ± SD: 3.7 ± 1.1 versus 4.5 ± 1.3 kg, p < 0.001) were significantly lower in the FWT group. The overall success rate in the FWT group was 95%. Image quality was slightly lower when using the FWT (mean ± SD: 3.7 ± 0.43 versus 3.96 ± 0.11, p < 0.001). Multivariate analysis showed a higher risk of acquiring sequences with diagnostic limitations in the FWT group (p < 0.001), increasing with corrected age (p = 0.048). CONCLUSION: The FWT is a highly successful method to perform MRI scans in term and preterm neonates. Overall image quality is only slightly lower than under sedation. Especially in immature low-weight preterm patients, the FWT is a reliable option to perform MRI studies without exposing the child to risks associated with sedation. CLINICAL RELEVANCE STATEMENT: The "feed-and-wrap" technique enables high-quality MRI examinations in neonates, including low-weight premature patients. Deep sedation for diagnostic MRI procedures in this age group, which has the risk of short- and long-term complications, can often be avoided. KEY POINTS: Deeply sedating neonates for MR examinations comes with risks. Image quality is only slightly lower when using the "feed-and-wrap" technique. The "feed-and-wrap" technique is feasible even in low-weight premature infants.


Asunto(s)
Sedación Profunda , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Recién Nacido , Estudios Retrospectivos , Masculino , Femenino , Sedación Profunda/métodos , Recien Nacido Prematuro
8.
Infection ; 52(1): 129-137, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37423969

RESUMEN

OBJECTIVES: The objective of this study was to identify the pathogen spectrum of community acquired pneumonia in people living with HIV (PLWH), and to compare it with a matched HIV negative group in order to reassess therapeutic strategies for PLWH. METHODS: Seventy-three (n = 73) PLWH (median CD4 3-6 months before CAP: 515/µl; SD 309) with community acquired pneumonia (CAP) were matched with 218 HIV-negative CAP controls in a prospective study design. Pathogen identifications used blood culture, samples from the upper and lower respiratory tract (culture and multiplex PCR) and urinary pneumococcal and legionella antigen test. RESULTS: Although the vaccination rate among PLWH with CAP was significantly higher (pneumococcal vaccination: 27.4 vs. 8.3%, p < 0.001; influenza vaccination: 34.2 vs. 17.4%, p = 0.009), pneumococci were found most frequently as pathogen among both PLWH (n = 19/21.3%) and controls (n = 34/17.2%; p = 0.410), followed by Haemophilus influenzae (PLWH, n = 12/13.5%, vs. controls, n = 25 / 12.6%; p = 0.850). Staphylococcus aureus was found equally in 20.2 and 19.2% in PLWH and controls, but infection or colonization could not be distinguished. Mortality during 6-month follow-up was significantly higher for PLWH (5/73, or 6.8%) versus controls (3/218, or 1.4%), however with lower case numbers than previously reported. Typical HIV-associated pathogens such as Pneumocystis jirovecii were found only exceptionally. CONCLUSIONS: Our study underscores the persistent clinical burden of CAP for PLWH. From pathogen perspective, empirical antibiotic treatment for CAP in PLWH on antiretroviral therapy should cover pneumococci and Haemophilus influenzae and may be adopted from valid common recommendations.


Asunto(s)
Infecciones Comunitarias Adquiridas , Infecciones por VIH , Infecciones por Haemophilus , Neumonía Bacteriana , Humanos , Neumonía Bacteriana/epidemiología , Estudios Prospectivos , Streptococcus pneumoniae , Antibacterianos/uso terapéutico , Infecciones por Haemophilus/tratamiento farmacológico , Haemophilus influenzae , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/tratamiento farmacológico
9.
Infection ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042326

RESUMEN

PURPOSE: Doxycycline post-exposure prophylaxis (Doxy-PEP) reduces the likelihood of Chlamydia and early syphilis by approximately two-thirds. Currently, data on the frequency of Doxy-PEP use in men who have sex with men (MSM) are limited. This study aimed to assess knowledge, attitude towards, and frequency of Doxy-PEP use among MSM in Germany. METHODS: We conducted a national online survey in Germany from summer to fall 2023, recruiting MSM and transgender women. Participants were invited to complete the online survey through social media, online dating platforms, and print media advertisements with active recruitment and poster advertising in private practices, tertiary outpatient clinics, and MSM community events in Germany. RESULTS: In total, 438 participants completed the survey and were included in the analysis, and 285 (65.1%) were living with the human immunodeficiency virus (HIV) or taking HIV-pre-exposure prophylaxis (PrEP). Overall, 170 participants (38.8%) had heard of Doxy-PEP, and 275 (62.8%) would consider taking it, but only 32 (7.3%) reported having ever taken Doxy-PEP. The most common reason for a negative attitude towards Doxy-PEP were apprehension about insufficient detailed information, and concerns about antibiotic resistance. Doxy-PEP users were more likely to be on HIV-PrEP, had a higher self-reported risk of bacterial sexually transmitted infections (STIs), and often had a history of bacterial STIs. CONCLUSION: The study demonstrated high awareness and strong interest in Doxy-PEP among MSM in Germany, most of whom were living with HIV or taking HIV-PrEP; however, the actual usage of Doxy-PEP remains low in the summer and fall of 2023.

10.
Eur Phys J E Soft Matter ; 47(1): 8, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270681

RESUMEN

We study the formation of vesicle condensates induced by the protein synapsin, as a cell-free model system mimicking vesicle pool formation in the synapse. The system can be considered as an example of liquid-liquid phase separation (LLPS) in biomolecular fluids, where one phase is a complex fluid itself consisting of vesicles and a protein network. We address the pertinent question why the LLPS is self-limiting and stops at a certain size, i.e., why macroscopic phase separation is prevented. Using fluorescence light microscopy, we observe different morphologies of the condensates (aggregates) depending on the protein-to-lipid ratio. Cryogenic electron microscopy then allows us to resolve individual vesicle positions and shapes in a condensate and notably the size and geometry of adhesion zones between vesicles. We hypothesize that the membrane tension induced by already formed adhesion zones then in turn limits the capability of vesicles to bind additional vesicles, resulting in a finite condensate size. In a simple numerical toy model we show that this effect can be accounted for by redistribution of effective binding particles on the vesicle surface, accounting for the synapsin-induced adhesion zone.

11.
Nano Lett ; 23(23): 10796-10801, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37862690

RESUMEN

Eukaryotic cells contain membrane-bound and membrane-less organelles that are often in contact with each other. How the interface properties of membrane-less organelles regulate their interactions with membranes remains challenging to assess. Here, we employ graphene-based sensors to investigate the electrostatic properties of synapsin 1, a major synaptic phosphoprotein, either in a single phase or after undergoing phase separation to form synapsin condensates. Using these graphene-based sensors, we discover that synapsin condensates generate strong electrical responses that are otherwise absent when synapsin is present as a single phase. By introducing atomically thin dielectric barriers, we show that the electrical response originates in an electric double layer whose formation governs the interaction between synapsin condensates and graphene. Our data indicate that the interface properties of the same protein are substantially different when the protein is in a single phase versus within a biomolecular condensate, unraveling that condensates can harbor ion potential differences at their interface.


Asunto(s)
Condensados Biomoleculares , Grafito , Grafito/metabolismo , Sinapsinas , Proteínas , Orgánulos
12.
Stroke ; 54(11): 2895-2905, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37746704

RESUMEN

BACKGROUND: Prediction of poststroke outcome using the degree of subacute deficit or magnetic resonance imaging is well studied in humans. While mice are the most commonly used animals in preclinical stroke research, systematic analysis of outcome predictors is lacking. METHODS: We intended to incorporate heterogeneity into our retrospective study to broaden the applicability of our findings and prediction tools. We therefore analyzed the effect of 30, 45, and 60 minutes of arterial occlusion on the variance of stroke volumes. Next, we built a heterogeneous cohort of 215 mice using data from 15 studies that included 45 minutes of middle cerebral artery occlusion and various genotypes. Motor function was measured using a modified protocol for the staircase test of skilled reaching. Phases of subacute and residual deficit were defined. Magnetic resonance images of stroke lesions were coregistered on the Allen Mouse Brain Atlas to characterize stroke topology. Different random forest prediction models that either used motor-functional deficit or imaging parameters were generated for the subacute and residual deficits. RESULTS: Variance of stroke volumes was increased by 45 minutes of arterial occlusion compared with 60 minutes. The inclusion of various genotypes enhanced heterogeneity further. We detected both a subacute and residual motor-functional deficit after stroke in mice and different recovery trajectories could be observed. In mice with small cortical lesions, lesion volume was the best predictor of the subacute deficit. The residual deficit could be predicted most accurately by the degree of the subacute deficit. When using imaging parameters for the prediction of the residual deficit, including information about the lesion topology increased prediction accuracy. A subset of anatomic regions within the ischemic lesion had particular impact on the prediction of long-term outcomes. Prediction accuracy depended on the degree of functional impairment. CONCLUSIONS: For the first time, we developed and validated a robust tool for the prediction of functional outcomes after experimental stroke in mice using a large and genetically heterogeneous cohort. These results are discussed in light of study design and imaging limitations. In the future, using outcome prediction can improve the design of preclinical studies and guide intervention decisions.

13.
HIV Med ; 24(4): 389-397, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36059149

RESUMEN

BACKGROUND: Since May 2022, increasing numbers of monkeypox virus (MPXV) infections have been reported from across Europe and North America. Studies, mainly from Africa, have suggested a higher risk for severe MPXV cases in people living with HIV. METHODS: This was a retrospective study of all confirmed MPXV infections observed in the participating centres since 19 May 2022. We conducted a chart review to evaluate clinical characteristics, comorbidities, and coinfections, including HIV, viral hepatitis, and sexually transmitted infections (STIs). RESULTS: By 30 June 2022, a total of 546 MPXV infections were reported from 42 German centres. All patients were men who have sex with men (MSM), of whom 256 (46.9%) were living with HIV, mostly with a preserved immune system and with viral suppression. In total, 232 (42.5%) MSM were also taking HIV pre-exposure prophylaxis (PrEP) and 58 (10.6%) MSM had no known HIV infection or PrEP use. The median age was 39 years (range 20-67), and comorbidities were rare. However, 52.4% and 29.4% of all patients had been diagnosed with at least one STI within the last 6 months or within the last 4 weeks, respectively. The most frequent localizations of MPXV infection were genital (49.9%) and anal (47.9%), whereas fever (53.2%) and lymphadenopathy (42.6%) were the most frequent general symptoms. The hospitalization rate was low (4.0%), and no fatal course was observed. The clinical picture showed no apparent differences between MSM with or without HIV. CONCLUSIONS: In this preliminary cohort analysis from a current large outbreak among MSM in Germany, the clinical picture of MPXV infection did not differ between MSM with and without HIV infection. Severe courses were rare and hospitalization rates were low. However, most patients were relatively healthy, and only a few people living with HIV were viremic or severely immunosuppressed.


Asunto(s)
Infecciones por VIH , Mpox , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Enfermedades de Transmisión Sexual , Masculino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Monkeypox virus , Estudios Retrospectivos , Enfermedades de Transmisión Sexual/epidemiología , Alemania/epidemiología
14.
AIDS Care ; 35(11): 1749-1759, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-36912672

RESUMEN

Delayed HIV diagnosis at advanced stages of disease remains common (33%-64%). This analysis of the multi-center FindHIV study including newly diagnosed HIV-infected adults in Germany, focused on the potential role of socio-demographic and psychological factors on late diagnosis (formerly "late presentation", AIDS diagnosis or CD4 cells <350/µL). These data were collected from patient profiles, physician-patient interviews and questionnaires. Participating centers (n = 40) represented the diverse health care settings in HIV care and geographic regions. Of 706 newly diagnosed adults (92% male, median age 39 years) between 2019 and 2020, 55% (388/706) were diagnosed late with a median CD4 cell count of 147/µL; 20% (142/706) presented with AIDS. From the physicians' perspective, earlier diagnosis would have been possible in 45% of participants (late versus non-late presentation 58% versus 29%). The most common physician-perceived reason was an underestimated risk for HIV infection by the patient (37%). In multivariable logistic regression analysis, older age, sexual contacts with both sexes as possible route of HIV transmission, being married, and a poor level of knowledge about HIV treatment were found to be associated with a significantly elevated risk for late presentation. Education, employment status, sexual relations, migration background and personality traits were not.Trial registration: German Clinical Trials Register (DRKS00016351).


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Adulto , Femenino , Humanos , Masculino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Factores de Riesgo , Determinantes Sociales de la Salud , Diagnóstico Tardío , Recuento de Linfocito CD4 , Alemania/epidemiología
15.
Eur Phys J E Soft Matter ; 46(12): 123, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38060069

RESUMEN

Vesicle pools can form by attractive interaction in a solution, mediated by proteins or divalent ions such as calcium. The pools, which are alternatively also denoted as vesicle clusters, form by liquid-liquid phase separation (LLPS) from an initially homogeneous solution. Due to the short range liquid-like order of vesicles in the pool or cluster, the vesicle-rich phase can also be regarded as a condensate, and one would like to better understand not only the structure of these systems, but also their dynamics. The diffusion of vesicles, in particular, is expected to change when vesicles are arrested in a pool. Here we investigate whether passive microrheology based on X-ray photon correlation spectroscopy (XPCS) is a suitable tool to study model systems of artificial lipid vesicles exhibiting LLPS, and more generally also other heterogeneous biomolecular fluids. We show that by adding highly scattering tracer particles to the solution, valuable information on the single vesicle as well as collective dynamics can be inferred. While the correlation functions reveal freely diffusing tracer particles in solutions at low CaCl[Formula: see text] concentrations, the relaxation rate [Formula: see text] shows a nonlinear dependence on [Formula: see text] at a higher concentration of around 8 mM CaCl[Formula: see text], characterised by two linear regimes with a broad cross-over. We explain this finding based on arrested diffusion in percolating vesicle clusters.

16.
Cancer ; 128(2): 260-268, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34592009

RESUMEN

BACKGROUND: Previous studies have shown that men with HIV and germ cell cancer (HIV-GCC) have inferior overall survival (OS) in comparison with their HIV-negative counterparts. However, little information is available on treatments and outcomes of HIV-GCC in the era of combination antiretroviral therapy (cART). METHODS: This study examined men living with HIV who were 18 years old or older and had a diagnosis of histologically proven germ cell cancer (GCC). The primary outcomes were OS and progression-free survival (PFS). RESULTS: Data for 89 men with a total of 92 HIV-GCCs (2 synchronous GCCs and 1 metachronous bilateral GCC) were analyzed; among them were 64 seminomas (70%) and 28 nonseminomas (30%). The median age was 36 years, the median CD4 T-cell count at GCC diagnosis was 420 cells/µL, and 77% of the patients on cART had an HIV RNA load < 500 copies/mL. Stage I disease was found in 44 of 79 gonadal GCCs (56%). Among 45 cases with primary disseminated GCC, 78%, 18%, and 4% were assigned to the good-, intermediate-, and poor-prognosis groups, respectively, of the International Germ Cell Cancer Collaborative Group. Relapses occurred in 14 patients. Overall, 12 of 89 patients (13%) died. The causes of death were refractory GCC (n = 5), an AIDS-defining illness (n = 3), and other causes (n = 4). After a median follow-up of 6.5 years, the 5- and 10-year PFS rates were 81% and 73%, respectively, and the 5- and 10-year OS rates were 91% and 85%, respectively. CONCLUSIONS: The 5- and 10-year PFS and OS rates of men with HIV-GCC were similar to those reported for men with HIV-negative GCC. Patients with HIV-GCC should be managed identically to HIV-negative patients. LAY SUMMARY: Men living with HIV are at increased risk for germ cell cancer (GCC). Previous studies have shown that the survival of men with HIV-associated germ cell cancer (HIV-GCC) is poorer than the survival of their HIV-negative counterparts. This study examined the characteristics, treatments, and outcomes of 89 men with HIV-GCC in the era of effective combination antiretroviral therapies. The long-term outcomes of men with HIV-GCC were similar to those reported for men with HIV-negative GCC. Patients with HIV-GCC should be managed identically to HIV-negative patients.


Asunto(s)
Infecciones por VIH , Neoplasias de Células Germinales y Embrionarias , Seminoma , Neoplasias Testiculares , Adolescente , Adulto , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Recurrencia Local de Neoplasia , Seminoma/patología , Neoplasias Testiculares/patología
17.
J Neuroinflammation ; 19(1): 172, 2022 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-35780157

RESUMEN

BACKGROUND: Deposition of amyloid beta (Aß) and hyperphosphorylated tau along with glial cell-mediated neuroinflammation are prominent pathogenic hallmarks of Alzheimer's disease (AD). In recent years, impairment of autophagy has been identified as another important feature contributing to AD progression. Therefore, the potential of the autophagy activator spermidine, a small body-endogenous polyamine often used as dietary supplement, was assessed on Aß pathology and glial cell-mediated neuroinflammation. RESULTS: Oral treatment of the amyloid prone AD-like APPPS1 mice with spermidine reduced neurotoxic soluble Aß and decreased AD-associated neuroinflammation. Mechanistically, single nuclei sequencing revealed AD-associated microglia to be the main target of spermidine. This microglia population was characterized by increased AXL levels and expression of genes implicated in cell migration and phagocytosis. A subsequent proteome analysis of isolated microglia confirmed the anti-inflammatory and cytoskeletal effects of spermidine in APPPS1 mice. In primary microglia and astrocytes, spermidine-induced autophagy subsequently affected TLR3- and TLR4-mediated inflammatory processes, phagocytosis of Aß and motility. Interestingly, spermidine regulated the neuroinflammatory response of microglia beyond transcriptional control by interfering with the assembly of the inflammasome. CONCLUSIONS: Our data highlight that the autophagy activator spermidine holds the potential to enhance Aß degradation and to counteract glia-mediated neuroinflammation in AD pathology.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Espermidina , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/efectos de los fármacos , Péptidos beta-Amiloides/metabolismo , Animales , Modelos Animales de Enfermedad , Ratones , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Espermidina/farmacología , Espermidina/uso terapéutico
18.
Hematol Oncol ; 40(5): 922-929, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35857866

RESUMEN

We assessed the long-term outcomes and treatment-related adverse effects of patients with Stage I, "orbital-type" lymphomas that were uniformly treated with photons. All consecutive patients diagnosed with low-grade, Ann Arbor Stage IEA orbital lymphoma treated between 1999 and 2020 at our department were retrospectively reviewed. We excluded patients with exclusive conjunctival involvement, typically treated with en face electrons. In order to quantify radiotherapy related side effects we applied the CTCAE criteria, analyzed changes in visual acuity, quantified dry eye symptoms by use of the Ocular Surface Disease Index (OSDI) score and applied the EORTC QLQ-C30 questionnaire for quality of life (QoL) assessment. In total 66 eyes of 62 patients were irradiated with a median dose of 30.6 Gy. The median follow-up was 43.5 months. The predominant histological subtype were MALT lymphomas. No local failure occurred in this cohort. Of nine outfield relapses, six solely occurred in the contralateral eye. The 5- and 10- years distant progression free survival rates (PFS) were 81.4% and 63.5%. The 5- and 10-years overall survival rates were 85.1% and 71.9% without any tumor related death. Of the acute toxicities none was higher than CTCAE grade 1. The predominant late toxicities were dry eyes (21.2%) of CTCAE Grade <2 and radiation induced cataracts (19.7%). During long-term follow up the average visual acuity did not deteriorate. The global QoL was worst before treatment and improved significantly after 24 months (p = 0.007). External beam radiotherapy of "orbital-type" lymphomas with photons is an effective and gentle treatment option with excellent local control rates. From the high control rates the trend to use slightly lower total doses of 24-27 Gy with conventional fractionation is supported. As non-coplanar radiotherapy techniques improved and total doses can slightly be reduced, the current status of radiotherapy as first line therapy is provided.


Asunto(s)
Supervivientes de Cáncer , Linfoma , Neoplasias Orbitales , Humanos , Neoplasias Orbitales/radioterapia , Calidad de Vida , Estudios Longitudinales , Estudios de Seguimiento , Estudios Retrospectivos , Linfoma/radioterapia
19.
Neurosurg Rev ; 45(4): 2533-2546, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35384543

RESUMEN

While many centers nowadays offer minimally invasive techniques for the treatment of single suture synostosis, surgical techniques and patient management vary significantly. We provide an overview of how scaphocephaly treated with endoscopic techniques is managed in the reported series and analyze the crucial steps that need to be dealt with during the management process. We performed a review of the published literature including all articles that examined sagittal-suture synostosis treated with endoscopic techniques as part of single- or multicenter studies. Fourteen studies reporting results of 885 patients were included. We identified 5 key steps in the management of patients. A total of 188 patients were female and 537 male (sex was only specified in 10 articles, for 725 included patients, respectively). Median age at surgery was between 2.6 and 3.9 months with a total range from 1.5 to 7.0 months. Preoperative diagnostics included clinical and ophthalmologic examinations as well as neuropsychological and genetic consultations if needed. In 5 publications, a CT scan was routinely performed. Several groups used anthropometric measurements, mostly the cephalic index. All groups analyzed equally recommended to perform endoscopically assisted craniosynostosis surgery with postoperative helmet therapy in children < 3 months of age, at least for non-syndromic cases. There exist significant variations in surgical techniques and patient management for children treated endoscopically for single suture sagittal synostosis. This heterogeneity constitutes a major problem in terms of comparability between different strategies.


Asunto(s)
Suturas Craneales , Craneosinostosis , Niño , Suturas Craneales/cirugía , Craneosinostosis/cirugía , Craneotomía/métodos , Endoscopía/métodos , Femenino , Humanos , Lactante , Masculino , Periodo Posoperatorio , Suturas , Resultado del Tratamiento
20.
J Dtsch Dermatol Ges ; 20(6): 892-905, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35711056

RESUMEN

Das Kaposi-Sarkom (KS) ist eine seltene, maligne, von lymphatischen Endothelzellen ausgehende, multilokuläre Gefäßerkrankung, die vor allem Haut und Schleimhäute, aber auch das lymphatische System und innere Organe wie den Gastrointestinaltrakt, die Lunge oder die Leber befallen kann. Fünf epidemiologische Subtypen des KS mit variablem klinischem Verlauf und unterschiedlicher Prognose werden unterschieden, die in spezifischen Populationen vermehrt auftreten: (1) klassisches KS, (2) iatrogenes KS bei Immunsuppression, (3) endemisches (afrikanisches) lymphadenopathisches KS, (4) epidemisches, HIV-assoziiertes KS und mit einem Immunrekonstitutions-Inflammations-Syndrom (IRIS) assoziiertes KS und (5) KS bei Männern, die Sex mit Männern haben (MSM) ohne HIV-Infektion. Diese interdisziplinäre Leitlinie fasst aktuelle praxisrelevante Empfehlungen zu Diagnostik und Therapie der verschiedenen Formen des KS zusammen. Die in dieser Kurzleitlinie genannten Empfehlungen werden in der Langfassung der Leitlinie (Online-Version des JDDG) detaillierter ausgeführt.

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