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Uusimmat julkaisut

Acquired and genetic drivers of C3 and C5 convertase dysregulation in C3 glomerulopathy and immunoglobulin-associated MPGN
(Oxford University Press, 2024-12) Roquigny, Julia; Meuleman, Marie-Sophie; El Sissy, Carine; Martins, Paula Vieira; Meri, Seppo; Duval, Anna; Le Quintrec, Moglie; Fakhouri, Fadi; Chauvet, Sophie; Fremeaux-Bacchi, Veronique; TRIMM - Translational Immunology Research Program; University of Helsinki; Department of Bacteriology and Immunology; HUSLAB; Seppo Meri / Principal Investigator; Research Programs Unit; HUS Chemistry and Microbiology
Dysregulation of the alternative pathway of complement plays a central role in the pathophysiology of C3 glomerulopathy (C3G). Various autoimmune and genetic factors targeting the alternative pathway have been associated with both C3G and primary immunoglobulin-associated membranoproliferative glomerulonephritis (Ig-MPGN), suggesting shared pathophysiological mechanisms. This review highlights the wide range of disease drivers identified that mainly target components or protein complexes of the alternative pathway, both in C3G and Ig-MPGN. Nephritic factors, which constitute a heterogeneous group of autoantibodies targeting the C3 or the C5 convertase, are the most common abnormalities. Monoclonal gammopathies are frequent in aging adults. They may promote complement activation and have in some cases also been found to target alternative pathway regulatory proteins. Additionally, some patients with C3G and Ig-MPGN carry rare variants in genes encoding complement activating or regulating proteins of the alternative pathway. This review provides an informative overview of pathogenetic mechanisms associated with each abnormality, acting at different steps in the complement cascade. The diversity of targets involved in the C3G pathophysiology suggests the potential benefit of therapeutical approaches tailored to the underlying disease drivers, with a pivotal impact upstream or at the level of the C3 or C5 convertase activity.
Does IPSS-R downstaging before transplantation improve the prognosis of patients with myelodysplastic neoplasms?
(Elsevier B.V., 2024-07-25) Scheid, Christof; Eikema, Diderik-Jan; van Gelder, Michel; Salmenniemi, Urpu; Maertens, Johan; Passweg, Jakob; Blaise, Didier; Byrne, Jennifer L.; Kröger, Nicolaus; Sockel, Katja; Chevallier, Patrice; Bourhis, Jean Henri; Cornelissen, Jan J.; Sengeloev, Henrik; Finke, Jürgen; Snowden, John A.; Gedde-Dahl, Tobias; Cornillon, Jérôme; Schanz, Urs; Patel, Amit; Koster, Linda; de Wreede, Liesbeth C.; Hayden, Patrick; Raj, Kavita; Drozd-Sokolowska, Joanna; Gurnari, Carmelo; Onida, Francesco; McLornan, Donal P.; Robin, Marie; Yakoub-Agha, Ibrahim; Clinicum; HUS Comprehensive Cancer Center; Department of Oncology
In patients with myelodysplastic syndrome (MDS), higher revised International Prognostic Scoring System (IPSS-R) scores at transplant are associated with worse transplant outcome and, thus, lowering IPSS-R scores by therapeutic intervention before transplantation may seem beneficial. However, there is no evidence, to date, to support this approach. In a retrospective analysis, a total of 1482 patients with MDS with sufficient data to calculate IPSS-R score at diagnosis and at time of transplantation were selected from the European Society for Blood and Marrow Transplantation transplant registry and analyzed for transplant outcome in a multivariable Cox model including IPSS-R score at diagnosis, treatment intervention, change in IPSS-R score before transplant, and several patient and transplant variables. Transplant outcome was unaffected by IPSS-R score change in untreated patients and moderately superior in patients treated with chemotherapy with improved IPSS-R score at transplant. Improved IPSS-R score after hypomethylating agents (HMAs) or other therapies showed no beneficial effect. However, when IPSS-R score progressed after chemotherapy, HMAs, or other therapies, transplant outcome was worse than without any prior treatment. Similar results were found when reduction or increase in bone marrow (BM) blasts between diagnosis and transplantation was considered. The results show a limited benefit of IPSS-R score downstaging or reduction of BM blasts after chemotherapy and no benefit for HMAs or other treatments and thus question the role of prior therapy in patients with MDS scheduled for transplantation. The model-based survival estimates should help inform decision-making for both doctors and patients.
Profiles of Approaches to Writing and Their Links to Self-Efficacy and LLM Acceptance in L2 Academic Writing
(2025-07-20) Sun, Fei; Mendoza, Laura; Wang, Junju; Li, Hongbin
Approaches to writing play an important role in both the writing processes and outcomes. However, little is known about whether L2 writers adopt different combinations of approaches in academic writing contexts and what factors predict such combinations. Hence, this study aimed to identify different profiles of approaches to writing in an L2 academic context and examine how they are predicted by writing self-efficacy and large language model (LLM) acceptance. To this end, a total of 578 Chinese graduate students were recruited to participate in the study. Latent profile analysis revealed three distinct writing profiles: unorganized (Profile 1), dissonant (Profile 2), and deep and organized (Profile 3), with the majority of students categorized under the dissonant profile. Additionally, multinomial logistic regression analysis revealed that writing self-efficacy positively predicted profile membership, with the strongest effect observed for Profile 3, followed by Profile 2 and then Profile 1. LLM acceptance also positively predicted profile membership, with the strongest effect for Profile 2, followed by Profile 3 and then Profile 1.
Highly selective uranium separation using sulfonic acid‑functionalized hierarchically porous zirconium phosphate: Modelling and mechanism study
(Elsevier, 2025) Zhang, Shouxin; Li, Xiaodong; Huang, Xinhui; Szlachta, Małgorzata; Bao, Hongli; Xu, Junhua; Geologian tutkimuskeskus; Geological Survey of Finland
The growing challenges of nuclear pollution necessitate the development of advanced sorption materials with high efficiency and improved selectivity. In this work, a hierarchical porous zirconium phosphate sorbent (H-ZrP) was synthesized via a facile self-assembly strategy, and its sulfonic acid-functionalized derivative (H-ZrP-SO3H) was developed for selective U(VI) removal. Comprehensive characterization demonstrates that H-ZrP possesses a unique hierarchical pore architecture, high specific surface area, and excellent thermal stability. Batch experiments reveal that both materials exhibit exceptional U(VI) sorption capacities: 372.4 mg g−1 for H-ZrP and 290.5 mg g−1 for H-ZrP-SO3H. Kinetic and isotherm analyses confirm chemisorption-dominated monolayer sorption, well-described by pseudo-second-order (R2 > 0.99) and Langmuir models (R2 > 0.98). H-ZrP-SO3H achieves higher selectivity in V/U systems despite reduced porosity due to optimized surface charge interactions. H-ZrP and H-ZrP-SO3H demonstrate outstanding reusability, retaining > 99 % removal efficiency after five sorption–desorption cycles with preserved structural integrity. Surface complexation modelling reveals that the sorption process is dominated by a multi-stage sorption mechanism: electrostatic attraction and surface complexation via oxygenated groups. In summary, this work presents highly efficient functionalized phosphate-based sorbents to regulate interfacial charge dynamics for enhanced U(VI) sorption.
The impact of large fires in boreal drained peatlands in western Finland: Ecohydrological drivers and carbon and nitrogen loss
(Elsevier, 2025) Turunen, Jukka; Rehell, Sakari; Sarkkola, Sakari; Vasander, Harri; Geologian tutkimuskeskus; Geological Survey of Finland
Climate change, characterized by more frequent drought periods along with anthropogenic activities, may increase the occurrence and severity of peatland wildfires in the boreal region. This study examines the impact of two large-scale peatland fires in 2020 and 2021 on carbon (C) and nitrogen (N) dynamics and losses in western Finland. The first site (Muhos, burned peatland area 217 ha) included both drained peatlands and pristine undrained mires, while the second (Susineva, burned peatland area 130 ha) was entirely drained for forestry. Our results reveal the significant impact of high-intensity fires on C and N dynamics and storage in drained peatlands, and in undrained mires with variable water regimes. In well-drained peatlands used for forestry, the average C and N losses during the fire were approximately 5.5 kg C m−2 and 123 g N m−2. This estimated C loss exceeds the typical range reported for fire-events in undrained boreal mires. In contrast, the C loss in the undrained or poorly drained area fell within the range observed for undrained mires. The measured fire severity was influenced by drainage intensity and the types of vegetation communities. In undrained mires, the upper aerobic layer, with stable water regime, tends to burn only superficially or may even remain unburnt. However, in shallow mires with a variable water regime, where the surface peat dries extensively during drought periods, the C loss caused by fire was comparable to drained peatlands. Our findings underscore the importance of understanding the ecosystem services provided by peatlands, particularly considering management-related drivers such as drainage and fires. These factors can severely impact the peatland C balance and overall vulnerability, including reduced fire resilience.
Revisiting universal extra-dimension model with gravity mediated decays
(Springer-Verlag, 2025-04-09) Ghosh, Kirtiman; Huitu, Katri; Sahu, Rameswar; Department of Physics; Helsinki Institute of Physics
We explore the collider phenomenology of the fat-brane realization of the Minimal Universal Extra Dimension (mUED) model, where Standard Model (SM) fields propagate in a small extra dimension while gravity accesses additional large extra dimensions. This configuration allows for gravity-mediated decay (GMD) of Kaluza-Klein (KK) particles, resulting in unique final states with hard photons, jets, massive SM bosons, and large missing transverse energy due to invisible KK gravitons. We derive updated constraints on the model's parameter space by recasting ATLAS mono-photon, di-photon, and multi-jet search results using 139 inverse femtobern of integrated luminosity data. Recognizing that current LHC search strategies are tailored for supersymmetric scenarios and may not fully capture the distinct signatures, we propose optimized strategies using machine learning algorithms to tag boosted SM bosons and enhance signal discrimination against SM backgrounds. These methods improve sensitivity to fat-brane mUED signatures and offer promising prospects for probing this model in future LHC runs.
Non-linear magnetic buoyancy instability and galactic dynamos
(Oxford University Press, 2025-06) Qazi, Yasin; Shukurov, A.; Tharakkal, D.; Gent, F. A.; Bendre, A. B.; Particle Physics and Astrophysics
Variation and prognostic potential of the gut antibiotic resistome in the FINRISK 2002 cohort
(Nature Publishing Group, 2025-07-01) Parnanen, Katariina; Ruuskanen, Matti O.; Sommeria-Klein, Guilhem; Laitinen, Ville; Kantanen, Pyry; Meric, Guillaume; Gazolla Volpiano, Camila; Inouye, Michael; Knight, Rob; Salomaa, Veikko; Havulinna, Aki S.; Niiranen, Teemu; Lahti, Leo; Medicum; Institute for Molecular Medicine Finland; Complex Disease Genetics
The spread of antibiotic-resistant bacteria has severely reduced the efficacy of antibiotics and now contributes to 1 million deaths annually. The gut microbiome is a major reservoir of antibiotic resistance in humans, yet the extent to which gut antibiotic resistance gene load varies within human populations and the drivers that contribute most to this variation remain unclear. Here, we demonstrate, in a representative cohort of 7095 Finnish adults, that socio-demographic factors, lifestyle, and gut microbial community composition shape resistance gene selection and transmission processes. Resistance was linked not only to prior use of antibiotics, as anticipated, but also to frequent consumption of fresh vegetables and poultry, two food groups previously reported to contain antibiotic-resistant bacteria. Interestingly, resistance was not linked to the consumption of high-fat and high-sugar foods, but was consistently higher in females and urban high-income individuals, who currently have generally lower mortality rates. Nevertheless, during the 17-year follow-up, high resistance was associated with a 1.07-fold increase in mortality risk, comparable to elevated blood pressure, and with a heightened risk of sepsis. These findings highlight risks and socio-demographic dimensions of antibiotic resistance that are particularly relevant in the current context of global urbanization and middle-class growth.
Forensic shotgun pellet examination - material detection with dual-energy computed tomography
(Springer-Verlag, 2025-07-08) Brix, Mikael; Junno, Juho-Antti; Lammentausta, Eveliina; Junno, Alina; Liimatainen, Timo; Niinimäki, Jaakko; Kiljunen, Juha; Oura, Petteri; Department of Forensic Medicine; University of Helsinki
Forensic shotgun wounds are relatively common worldwide. Shotguns are used for legal purposes such as hunting as well as for criminal activities. In addition, shotguns are used by military and law enforcement. Even though shotguns are often lethal from close distances, shotgun wounds require medical attention regardless of the shooting distance. As a result, patients with shotgun wounds are often treated in hospitals, and in lethal incidents, they are examined by forensic pathologists. Radiological imaging, computed tomography (CT) in particular, may constitute a part of the shotgun wound examination in both scenarios. CT may help to identify and locate the pellets and aid in wound characterization. It would be important to detect the pellet material as lead pellets, for example, are heavily toxic, and others, such as steel pellets may, as ferromagnetic, prevent some further imaging modalities such as magnetic resonance imaging from being employed. In this study, we wanted to experiment whether shotgun pellet material could be detected with radiological imaging utilizing dual-energy CT (DECT). Traditionally pellets are manufactured from heavily toxic lead, but due to environmental factors, other pellet materials such as steel, copper, tungsten, and bismuth are getting more and more popular. To conduct this study, various pellet materials were shot into ballistic gelatine blocks. The blocks then underwent DECT. Subsequently, each pellet was automatically segmented, and for these extracted pellets a dual-energy index (DEI) was computed. DEI values of the pellets were compared to determine whether this measure could be used to differentiate between the pellet materials. The DEI values (mean +/- standard deviation) were 0.212 +/- 0.006, 0.008 +/- 0.001, 0.187 +/- 0.002, 0.012 +/- 0.004, and 0.008 +/- 0.002 for steel, lead, copper, tungsten, and bismuth, respectively. The Wilcoxon rank sum test indicated that steel and copper pellets could be reliably differentiated from the other pellet materials. Our study demonstrated that DECT can reliably differentiate steel and copper shotgun pellets from other materials such as lead, tungsten, and bismuth. This capability may provide important additional information in medico-legal investigations and aid trauma centres treating patients with shotgun wounds.
Impaired Fertility and Sexual Function in Women With Hirschsprung Disease : Results From an International Multi-Centre Cross-Sectional Study
(John Wiley and Sons Inc, 2025-07-10) Davidson, Joseph R.; Mutanen, Annika; Granström, Anna Löf; Hoel, Anders Telle; Loukogeorgakis, Stavros P.; De Coppi, Paolo; Bjornland, Kristin; Wester, Tomas; Eaton, Simon; Pakarinen, Mikko P.; Curry, Joe; HUS Children and Adolescents; University of Helsinki; Children's Hospital; Clinicum; Lastenkirurgian yksikkö
Objective: Hirschsprung is a congenital disorder affecting the gastrointestinal tract. However, pelvic colorectal surgery in infancy has been hypothesised to impact gynaecological outcomes in later life. Describe sexual function and fertility outcomes in women with Hirschsprung disease compared to population controls. Assess factors associated with poor outcomes (sexual dysfunction and subfertility). Design: International multicentre cross-sectional cohort study with comparison to controls from the general population. Setting: Status post-discharge from paediatric services. Population: Female patients aged > 20 years. Methods: Validated questionnaire-based survey with linkage to patient medical records. Comparison with controls using univariate analyses. Main outcome measures: Sexual dysfunction (Female Sexual Function Index; FSFI <= 26), Subfertility at 1 and 2 years. Results: Sexual dysfunction as per the FSFI was more common in patients and associated with poor functional outcomes; sexual abstinence seemed to associate even more so with poor bowel outcomes. Subfertility was higher in patients compared to controls (1 year: 21/45 (47%) vs. 38/178 (21%), p = 0.0008; 2 years: 12/45 (27%) vs. 17/178 (10%), p = 0.004). There was an increased proportion of patients who had accessed fertility services (20/45 (44%) vs. 43/178 (24%); p = 0.009), the proportion of successful pregnancies in patients attempting to conceive with IVF (11/17 (65%) vs. 27/43 (63%); p = 1.0) was similar. Conclusions: These novel data suggest that women with Hirschsprung disease who have undergone reconstructive surgery may be at risk for adverse sexual function and fertility outcomes.