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Co-injection of the parasite Onchocerca ochengi and the caspase inhibitors z-VAD.fmk and boc-D.fmk into the natural vector Simulium damnosum s.l. led to significantly increased survival of the parasites. Subsequent in situ apoptosis detection assays demonstrated that in the case of boc-D.fmk the enhanced survival was due to a diminished apoptosis level of the microfilariae in vivo. Additional assays using O. ochengi microfilariae which were coinjected with serine protease inhibitors into S. damnosum s.l. revealed that certain serine protease inhibitors can reduce the level of apoptosis. [ABSTRACT FROM AUTHOR]

Nitrides represent a promising class of materials for a variety of applications. However, bulk synthesis remains a challenging task due to the stability of the N 2 molecule. In this study, we introduce a simple and scalable approach for synthesizing nitride bulk materials. Moderate reaction temperatures are achieved by using reactive starting materials, slow and continuous mixing of the starting materials, and by dissipating heat generated during the reaction. The impact on the synthesis of using different starting materials as nitrogen source and the influence of a flux were examined. γ-Sn 3 N 4 was selected as the model compound. The synthesis of pure γ-Sn 3 N 4 bulk material on a large scale has still been a challenge, although a few synthesis methods were already described in the literature. Here we synthesized γ-Sn 3 N 4 by metathesis reaction of argon-diluted SnCl 4 with Li 3 N, Mg 3 N 2 or Ca 3 N 2 as nitrogen sources. Products were characterized by powder X-ray diffraction, scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, dynamic flash combustion analysis, hot gas extraction analysis, X-ray photoelectron spectroscopy, Mössbauer spectroscopy and X-ray absorption and emission spectroscopy. Additionally, single-crystal diffraction data of γ-Sn₃N₄, previously unavailable, were successfully collected., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

Background & Aims: Selective elimination of virus-infected hepatocytes occurs through virus-specific CD8 T cells recognizing peptide-loaded MHC molecules. Herein, we report that virus-infected hepatocytes are also selectively eliminated through a cell-autonomous mechanism., Methods: We generated recombinant adenoviruses and genetically modified mouse models to identify the molecular mechanisms determining TNF-induced hepatocyte apoptosis in vivo and used in vivo bioluminescence imaging, immunohistochemistry, immunoblot analysis, RNAseq/proteome/phosphoproteome analyses, bioinformatic analyses, mitochondrial function tests., Results: We found that TNF precisely eliminated only virus-infected hepatocytes independently of local inflammation and activation of immune sensory receptors. TNF receptor I was equally relevant for NF-kB activation in healthy and infected hepatocytes, but selectively mediated apoptosis in infected hepatocytes. Caspase 8 activation downstream of TNF receptor signaling was dispensable for apoptosis in virus-infected hepatocytes, indicating an unknown non-canonical cell-intrinsic pathway promoting apoptosis in hepatocytes. We identified a unique state of mitochondrial vulnerability in virus-infected hepatocytes as the cause for this non-canonical induction of apoptosis through TNF. Mitochondria from virus-infected hepatocytes showed normal biophysical and bioenergetic functions but were characterized by reduced resilience to calcium challenge. In the presence of unchanged TNF-induced signaling, reactive oxygen species-mediated calcium release from the endoplasmic reticulum caused mitochondrial permeability transition and apoptosis, which identified a link between extrinsic death receptor signaling and cell-intrinsic mitochondrial-mediated caspase activation., Conclusion: Our findings reveal a novel concept in immune surveillance by identifying a cell-autonomous defense mechanism that selectively eliminates virus-infected hepatocytes through mitochondrial permeability transition., Lay Summary: The liver is known for its unique immune functions. Herein, we identify a novel mechanism by which virus-infected hepatocytes can selectively eliminate themselves through reduced mitochondrial resilience to calcium challenge., Competing Interests: Conflict of interest The authors declare no conflicts of interest that pertain to this work. Please refer to the accompanying ICMJE disclosure forms for further details., (Copyright © 2020 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Plain English Summary: Patients usually understand their disease and lifestyle needs better than many medical professionals. They also have important ideas about what research would be most beneficial to their lives, especially on how to manage symptoms in a way that improves daily quality of life. In the UK, the National Institute for Health Research has recognised the value of patient insight, and now requires researchers with public funding to involve patients and the public throughout the research process. There are many opportunities for involvement, but these generally focus on improving study design to ensure the trial is acceptable to participants. Some programmes work towards setting research priorities as important to patients, public members, and medical experts, but due to the complexity and cost involved in running clinical trials, the majority of research originates with the pharmaceutical industry or academic institutions. There is a clear mismatch between research ideas that patients prioritise (quality of life), and those actually investigated (drug development).The Patient Led Research Hub (PLRH) is a new initiative hosted by the Cambridge Clinical Trials Unit. The PLRH supports research ideas as proposed by patient organisations, providing resources and expertise in research design and delivery. The PLRH aims to co-produce any technically feasible project, regardless of disease or symptom focus. The proposing patient group maintains ownership of the project with an active role in study management. This method of research has proven to produce credible research studies that are of direct relevance to patients., Abstract: Patient and Public Involvement has become an indispensable and expected component of healthcare research in the United Kingdom, largely driven by the National Institute of Health Research and other research funders. Opportunities for patients to become involved in research abound, and many organisations now have dedicated 'public involvement' teams. However, its value is often questioned amidst criticism of tokenism and the recognition that a mismatch persists between patient priorities and funded research. Although patients are frequently consulted, evidence that their involvement influences the research agenda remains limited. We propose a novel model that allows patients and the public not only to propose research questions, but to design, initiate and deliver their own research with all the necessary support from research professionals. We demonstrate the feasibility and utility of this approach in reporting the establishment, experiences and progress of the Patient Led Research Hub. Using this resource, patient organisations are now able to initiate and conduct rigorous clinical research unfettered by the constraints of academic or economic agendas., Competing Interests: SK left the CCTU in September 2017 to join the European Clinical Research Infrastructure Network as Clinical Operations Manager.Not applicable.Not applicable.The authors declare that they have no competing interests. TFH affirms that the manuscript is an honest, accurate and transparent account of the work reported, and that there are no omissions.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Aims: Current treatment for primary central nervous system lymphoma (PCNSL) involves high-dose methotrexate (HDMTX) with or without radiotherapy. Many published studies describing this approach include a highly selected group of patients. We report a single-centre experience of unselected cases of PCNSL., Materials and Methods: We retrospectively reviewed the case notes of 55 consecutive patients diagnosed with biopsy-proven PCNSL between 1995 and 2003 at Addenbrooke's Hospital Cambridge, UK. We describe the treatment and outcome, including survival, treatment-related toxicity and long-term functional disability., Results: At diagnosis, 45% of patients were considered unfit to receive treatment with HDMTX, owing to poor performance status or comorbidity. These patients had a median survival of 46 days and may not have been included in other published studies. The remaining patients were treated with a chemotherapy regimen, which included HDMTX. Patients who received at least one cycle of a chemotherapy containing HDMTX had a median survival of 31 months. Forty per cent did not complete planned chemotherapy owing to toxicity, disease progression or death. The median survival of patients treated with HDMTX aged 60 years compared with patients aged under 60 years was 26 months vs 41 months (P = 0.07), respectively. Younger patients treated with HDMTX, who achieved complete remission with chemotherapy, had a median survival of 56 months. We identified a high incidence of functional disability among survivors, resulting from a combination of the tumour itself, the neurosurgical procedure required for diagnosis and the late neurotoxicity of combined chemoradiotherapy., Conclusion: The treatment of PCNSL is associated with significant early and late toxicity. Further attempts to improve treatment should address mechanisms to reduce this toxicity. In particular, the benefit of radiotherapy in patients who achieve complete remission with HDMTX will remain uncertain until it is addressed in a multicentre, randomised trial.

A new family of fatty acid- and retinoid-binding proteins has recently been identified in nematodes. These are apparently nematode specific and have very different structures and binding characteristics to their mammalian counterparts. Retinoids have important roles in vision, tissue differentiation and repair, and can profoundly affect collagen synthesis. Binding proteins released by a parasite might therefore play a part in the generation of the skin and eye pathology seen in river blindness. They might also be involved in the formation of the subcutaneous nodules induced by this parasite.

Ov20 is a structurally novel 20-kDa retinol binding protein secreted by Onchocerca volvulus. Immunological and biological investigation of this protein has been hampered by the inability to maintain O. volvulus in a laboratory setting. In an effort to find a system more amenable to laboratory investigation, we have cloned, sequenced, and expressed cDNA encoding homologues of Ov20 from two closely related filarial species, Brugia malayi (Bm20) and Acanthocheilonema viteae (Av20). Sequence comparisons have highlighted differences in glycosylation of the homologues. We present here an analysis of mouse immune responses to Ov20, Bm20, and Av20. The results suggest a strong genetic restriction in response to native Bm20 that is overcome when recombinant, nonnative material is used. Reactivity of human filarial sera to the three recombinant proteins confirmed previous specificity studies with Ov20 but highlighted important differences in the reactivity patterns of the O. volvulus and B. malayi homologues that may be due to differences in glycosylation patterns. Ov20 is a dominant antigen in infected individuals, while Bm20 is not. The availability of the B. malayi homologue enabled us to use defined murine reagents and inbred strains for genetic analysis of responsiveness in a way that is not possible for Ov20. However, the close sequence similarity between Ov20 and Av20 suggests that the A. viteae model may be more suited to the investigation of the biological functions of Ov20.

Phenoloxidase (PO) is the key enzyme for melanin synthesis and plays an important role in the defense and recognition of pathogens in insects and other arthropods. We now report the upregulated transcription of the gene encoding the precursor of PO, prophenoloxidase, in Onchocerca-infected Simulium damnosum s.l., the main vector of human and bovine onchocerciasis in subsaharan Africa. Using homology-based generic primers in a polymerase chain reaction-based targeted differential display, the gene itself was identified and partially sequenced.

Vector-derived proteases are thought to be key to the regulation of filarial infections in Simulium damnosum s.I. To identify proteases of S. damnosum s.I. induced by infection with Onchocerca ochengi, a PCR-based differential display technique was used. By combining this method with homology-based serine protease primers transcripts can be detected from S. damnosum s.I. RNA.

Onchocerca ochengi, a bovine parasite, is a suitable model for research on human River Blindness. However, the microfilariae are normally found concomitantly with at least one of the other three bovine Onchocerca species O. dukei, O. gutturosa and O. armillata causing difficulties for the work on the microfilariae. We describe a simple and field applicable method for the separation of living O. ochengi microfilariae from the other Onchocerca species using Sephadex G-25 columns. Elution of mixed populations resulted in the passage of O. gutturosa and/or O. dukei in the initial 1 ml fraction with O. ochengi eluting as an almost 100% pure species in the 4th and 5th fractions.

The persistence of the effects of ivermectin on the viability, morphology and reproductivity of adult Onchocerca volvulus was examined eighteen months after treatment with a single or five six-monthly doses of ivermectin and compared with untreated controls. Treated nodules were removed from patients participating in a randomised controlled trial of ivermectin in Sierra Leone. Adult filariae, 545 females and 348 males, were isolated by collagenase digestion. The nodules were significantly smaller, contained fewer young worms and supported lower microfilarial production in those treated with five doses of ivermectin. The productivity index, a measure of the reproductive potential of a worm population, was still reduced by 83% eighteen months after five doses and by 63% after a single dose compared to controls. These results show that worms recover their fertility even after multiple doses of ivermectin, but do so slowly compared to standard dosage intervals. In addition ivermectin may have a partial chemoprophylactic effect which contributes to the maintenance of low microfilarial production in conditions of on-going transmission.

Purpose: Onchocerca volvulus, a filarial worm, is a major cause of infectious blindness and inflammatory eye disease. An autoimmune cause for ocular onchocerciasis has been suggested since the identification of a recombinant antigen of O. volvulus that shows immunologic cross-reactivity with a host ocular component of 44,000 M(r). The aim of this study was to establish the distribution of the cross-reactive antigens in both host tissues and the parasite, and to determine if significant autoantibody responses to the host antigen could be detected in infected persons., Methods: The tissue and organ distribution of the 44,000 M(r) antigen was determined by immunocytochemistry and Western blot analysis. Human autoantibody responses to the ocular antigen were demonstrated by Western blot analysis using sera collected from persons with onchocerciasis, with and without posterior segment pathology, Bancroftian filariasis, and Europeans with no filarial infection., Results: The tissue distribution of the 44,000 M(r) antigen correlates with the sites of pathology in onchocerciasis and antibody reactivity against this antigen could be detected in all persons with onchocerciasis and posterior segment pathology. The antigen is also recognized by sera from persons with Bancroftian filariasis, but not from normal persons., Conclusions: A role is proposed for immunologic cross-reactivity in the pathogenesis of onchocerciasis and it is suggested that intraocular presentation of the cross-reactive parasite antigen by microfilariae is essential for the development of disease.

Testicular examination of male Onchocerca dukei and German O. tarsicola revealed five pairs of chromosomes, which is typical of most filariae. In contrast to German O. tarsicola, specimens from Sweden had only three pairs of chromosomes.

A simple technique for the identification of the different spermatogenetic stages of Onchocerca volvulus is described. It is practicable for large-scale examinations in the field. The reproductivity of male worm populations can be assessed and directly correlated with the corresponding female worm populations. The activity of male filariae decreases with the increasing age of the worm population. Only few male worms transmit spermatozoa during mating, but spermatogenesis is continous also in very old male individuals. These old male filariae store high numbers of spermatozoa and cease their migration between the nodules.

One hundred and ninety eight patients with moderate to heavy infections with Onchocerca volvulus were randomly assigned to receive single doses of 100, 150 or 200 mcg/kg of ivermectin or matching placebo capsules. Detailed systemic, ocular and parasitological examinations were carried out at intervals over a period of one year. Nodules were excised twelve months after treatment to evaluate the effect of the treatment with ivermectin in adult O. volvulus. The three ivermectin-treated groups produced massive reductions in skin microfilariae (over 97%) with low levels being maintained over one year. The 150 and 200 mcg/kg doses were however superior to the 100 mcg/kg dose in achieving a greater reduction in skin microfilarial counts initially and in maintaining significant lower levels throughout the period of observation. There was no difference between the 150 and 200 mcg/kg doses at anytime. The three ivermectin doses were equally effective in the clearance of ocular microfilariae. The proportion of dead adult worms was very high in all treatment groups, which is effected by the successful ten years lasting vector control in northern Ghana. In spite of this superannuation of the worm population, an impact of the treatment with ivermectin on the reproductivity of the parasite could be shown. Systemic total clinical reaction was mild and was similar in the ivermectin treated groups. However, severe symptomatic postural hypotension (SSPH) was limited to patients treated with 150 or 200 mcg/kg of ivermectin. Ocular reactions were mild in all patients and no ocular deficiency occurred.(ABSTRACT TRUNCATED AT 250 WORDS)