The dominance of sex in Metazoa is enigmatic. Sexual species allocate resources to the production of males, while potentially facing negative effects such as the loss of well-adapted genotypes due to recombination, and exposure to diseases and predators during mating. Two major hypotheses have been put forward to explain the advantages of parthenogenetic versus sexual reproduction in animals, that is, the Red Queen hypothesis and the Tangled Bank/Structured Resource Theory of Sex. The Red Queen hypothesis assumes that antagonistic predator-prey/ parasite-host interactions favor sex. The Structured Resource Theory of Sex predicts sexual reproduction to be favored if resources are in short supply and aggregated in space. In soil, a remarkable number of invertebrates reproduce by parthenogenesis, and this pattern is most pronounced in oribatid mites (Oribatida, Acari). Oribatid mites are abundant in virtually any soil across very different habitats, and include many sexual and parthenogenetic (thelytokous) species. Thereby, they represent an ideal model group to investigate the role of sexual versus parthenogenetic reproduction across different ecosystems and habitats. Here, we compiled data on oribatid mite communities from different ecosystems and habitats across biomes, including tropical rainforests, temperate forests, grasslands, arable fields, salt marshes, bogs, caves, and deadwood. Based on the compiled dataset, we analyzed if the percentage of parthenogenetic species and the percentage of individuals of parthenogenetic species are related to total oribatid mite density, species number, and other potential driving factors of the reproductive mode including altitude and latitude. We then interpret the results in support of either the Red Queen hypothesis or the Structured Resource Theory of Sex. Overall, the data showed that low density of oribatid mites due to harsh environmental conditions is associated with high frequency of parthenogenesis supporting predictions of the Structured Resource Theory of Sex rather than the Red Queen hypothesis.
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http://dx.doi.org/10.1002/ece3.5303 | DOI Listing |
Clin Exp Allergy
January 2025
Division of Rheumatology and Clinical Immunology, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
This study demonstrates that patient advocacy groups significantly enhance medication availability and improve diagnosis of hereditary angioedema (HAE), particularly in emerging economies within the Asia-Pacific region. This study supports integrating patient advocacy group involvement into management guidelines, emphasising their role in improving access to diagnostics and treatment for HAE.
View Article and Find Full Text PDFBMJ Open Gastroenterol
December 2024
Florence Nightingale Faculty of Nursing Midwifery & Palliative Care, King's College London, London, UK
Objective: Many people with inflammatory bowel disease (IBD) experience fatigue, pain and faecal incontinence that some feel are inadequately addressed. It is unknown how many have potentially reversible medical issues underlying these symptoms.
Methods: We conducted a study testing the feasibility of a patient-reported symptom checklist and nurse-administered management algorithm ('Optimise') to manage common medical causes of IBD-related fatigue, pain and faecal incontinence.
Curr Opin Hematol
January 2025
Department of Biomedical and Molecular Sciences, Queen's University.
Purpose Of Review: To date, there is relatively limited research investigating changes in red blood cells (RBCs), particularly qualitative changes, in cancer patients and cancer patients receiving treatment. These changes may be important in better understanding cancer-associated anemia, which is the most prevalent hematological disorder in cancer patients with wide-ranging implications on patient care and quality of life. This review aims to summarize available evidence regarding qualitative and quantitative changes in RBCs in individuals with cancer prior to treatment and in patients undergoing treatment.
View Article and Find Full Text PDFN Engl J Med
December 2024
From the Department of Infectious Diseases and Hepatology Unit, Nanfang Hospital, Southern Medical University (J.H., X.L.), and the State Key Laboratory of Organ Failure Research, Key Laboratory of Infectious Diseases Research in South China, Ministry of Education, Guangdong Institute of Hepatology, Nanfang Hospital (J.H.), Guangzhou, the Department of Infectious Diseases and Biosafety Emergency Response, Huashan Hospital, Fudan University (W.Z.), the Department of Infectious Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine (Q.X.), Roche Holding (Q.B., E.C.), Roche Research and Development Center (C.C., Y.H.), and Takeda APAC Biopharmaceutical Research and Development (Q.B.), Shanghai, the Department of Hepatology, Center of Infectious Diseases and Pathogen Biology, First Hospital of Jilin University, Changchun (R.H.), the Center of Infectious Diseases, Laboratory of Infectious and Liver Disease, Institute of Infectious Diseases, West China Hospital, Sichuan University, Chengdu (H.T.), and the Department of Medicine and State Key Laboratory of Liver Research, Queen Mary Hospital, University of Hong Kong, Hong Kong (M.-F.Y.) - all in China; the Division of Infectious Diseases, University Hospital Álvaro Cunqueiro, Galicia Sur Health Research Institute, Servizo Galego de Saúde-Universidade de Vigo, Vigo, Spain (L.E.M.A.); the Division of Gastroenterology and Hepatology, Department of Internal Medicine, Taichung Veterans General Hospital (S.-S.Y.), and the Center for Digestive Medicine, Department of Internal Medicine, China Medical University Hospital, China Medical University (C.-Y.P.), Taichung, the Department of Internal Medicine, Changhua Christian Hospital, Changhua (W.-W.S.), Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung (W.-L.C.), and National Taiwan University Hospital, Taipei (J.-H.K.) - all in Taiwan; the Department of Internal Medicine, Hallym University College of Medicine, Chuncheon, South Korea (D.J.K.); the HIV Netherlands Australia Thailand Research Collaboration, Thai Red Cross AIDS Research Center and the Center of Excellence in Tuberculosis, Faculty of Medicine, Chulalongkorn University, Bangkok (A.A.), and the Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai (A.L.) - both in Thailand; Université de Paris-Cité, Department of Hepatology, Assistance Publique-Hôpitaux de Paris, Hôpital Beaujon, Centre de Recherche sur l'Inflammation, INSERM Unité Mixte de Recherche 1149, Paris (T.A.); F. Hoffmann-La Roche, Basel, Switzerland (F. Canducci, M.T.C., F. Chughlay, K.G., N.G., P.K., R.K., M.T.); Roche Products, Welwyn Garden City (S.D., V.P., B.S., R.U., C.W.), and ID Pharma Consultancy, Yelverton (C.W.) - both in the United Kingdom; Enthera Pharmaceuticals, Milan (F. Canducci); Parexel International, Hyderabad, India (A.P.); and the New Zealand Liver Transplant Unit, Auckland City Hospital, Auckland, New Zealand (E.G.).
Background: Xalnesiran, a small interfering RNA molecule that targets a conserved region of the hepatitis B virus (HBV) genome and silences multiple HBV transcripts, may have efficacy, with or without an immunomodulator, in patients with chronic HBV infection.
Methods: We conducted a phase 2, multicenter, randomized, controlled, adaptive, open-label platform trial that included the evaluation of 48 weeks of treatment with xalnesiran at a dose of 100 mg (group 1), xalnesiran at a dose of 200 mg (group 2), xalnesiran at a dose of 200 mg plus 150 mg of ruzotolimod (group 3), xalnesiran at a dose of 200 mg plus 180 μg of pegylated interferon alfa-2a (group 4), or a nucleoside or nucleotide analogue (NA) alone (group 5) in participants with chronic HBV infection who had virologic suppression with NA therapy. The primary efficacy end point was hepatitis B surface antigen (HBsAg) loss (HBsAg level, <0.
Crit Care
January 2025
Department of Clinical Epidemiology and Biostatistics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Rama VI Road, Rachatevi, Bangkok, 10400, Thailand.
Background: Continuous electroencephalography (cEEG) has been recommended in critically ill patients although its efficacy for improving patients' functional status remains unclear. This study aimed to compare the efficacy of Tele-cEEG with Tele-routine EEG (Tele-rEEG), in terms of seizure detection rate, mortality and functional outcomes.
Methods: This study is a 3-year randomized, controlled, parallel, multicenter trial, conducted in eight regional hospitals across Thailand.
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