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At least 19 recordsLinked to original sources
PubMed2025

Selecting candidate Neisseria gonorrhoeae strains for oropharyngeal gonorrhoea human challenge: a genomics-based analysis of clinical isolates.

BACKGROUND: Neisseria gonorrhoeae is a human pathogen of major public health importance due to its increasing global prevalence and antimicrobial resistance (AMR). Evidence suggests that oropharyngeal infection plays a key role in N gonorrhoeae transmission and AMR; however, our understanding of oropharyngeal gonorrhoea pathogenesis is poor. A controlled human infection model (CHIM) for oropharyngeal gonorrhoea will improve understanding of infection and accelerate urgently needed novel gonorrhoea prevention and therapeutic strategies. As the first step in the development of this CHIM, we describe a systematic approach to CHIM strain selection that leverages genomics and clinical data. METHODS: In this genomics-based analysis, we applied a systematic N gonorrhoeae challenge strain selection strategy incorporating genomic and clinical data to a primary dataset of clinical isolates of N gonorrhoeae collected from adult patients in Victoria, Australia, between Jan 1 and Dec 31, 2017, and July 1, 2019, and June 30, 2021. This selection strategy used clinical, phenotypic, and genomic characteristics to define a set of eight criteria that aimed to ensure the contemporary global clinical relevance of the candidate strains; select strains that would be applicable for the assessment of current and future gonorrhoea vaccines; and maximise participant safety by reducing the risk of disseminated gonococcal infection and clinically significant AMR. We applied these criteria to our primary dataset to generate a panel of potential challenge strains. From this final dataset of potential challenge strains, we predetermined that we would select up to ten isolates to proceed to the next stage of detailed phenotypic characterisation for final N gonorrhoeae CHIM strain selection. FINDINGS: 5881 isolates comprised the primary dataset. After application of the selection criteria, most of the isolates (5795 [98·6%] of 5881) were excluded, mostly due to having clinically significant AMR and poor contemporary global clinical relevance. The remaining 86 N gonorrhoeae challenge strain candidates comprised five multilocus sequence types and six N gonorrhoeae multiantigen sequence types, many of which were represented by a single isolate. Of these 86 strains, five isolates were selected to maximise coverage of the phylogenetically distinct groups within the 86 candidate challenge strains and ensure representation of strains collected from various anatomical sites. INTERPRETATION: We transparently describe a novel, systematic, and rational genomics-based strategy for oropharyngeal gonorrhoea CHIM strain selection that improves the efficiency and transparency of CHIM strain selection and enables identification of contemporary and clinically relevant potential challenge strains. A final N gonorrhoeae challenge strain will be selected from the subset of five shortlisted candidates after detailed phenotypic assessment. FUNDING: Medical Research Future Fund, Australian National Health and Medical Research Council and Australian Government Research Training Program.

Humans↗
PubMed1977

Cryptococcosis: a diagnostic challenge.

Human cryptococcosis is an exogenous human infection of increasing frequency and growing importance. Early diagnosis is essential for the clinical outcome, no matter whether the infection is primary or secondary to underlying disease. Reliable and quick diagnostic methods are outlined and some pitfalls are discussed. Direct microscopy is essential, followed by cultivation procedures and serologic tests.

Agglutination Tests↗
PubMed1979

The effect of various corticosteroids on the release of beta-glucuronidase from human leukocytes challenged with zymosan.

Seven corticosteroids were tested for their effect on the release of beta-glucuronidase when human white cells were challenged with zymosan. Stabilization was noted in two areas of dilution with every steroid but destabilization occurred at high concentrations. However, those steroids that stabilized effectively at low concentrations were also those which were the most potent vasoconstrictors.

Adrenal Cortex Hormones↗
PubMed2025

Variation in Severity of Symptoms Associated With Two Snow Mountain Virus Inocula.

Snow Mountain Virus (SMV), the prototype of genogroup II and genotype II Norovirus (NoV), was used in human challenge studies to examine the infectivity, pathogenicity, and immune response to NoV. Clinical and laboratory data from two previously completed SMV human challenge trials using two different inocula (primary and secondary) were analyzed to compare the infectivity, illness, viral shedding, and serum IgG conversion. The primary and secondary SMV inocula were sequenced for detecting single nucleotide mutations. Of 15 subjects challenged with the primary inoculum between 2000 and 2002, nine were infected, and seven presented with acute gastroenteritis. Of 33 subjects challenged with the secondary inoculum between 2016 and 2018, 25 were infected, and nine presented with acute gastroenteritis. There were no statistically significant differences in overall infection and illness rates between subjects challenged with the primary inoculum versus the secondary inoculum. However, subjects infected with the primary inoculum experienced more severe clinical symptoms of acute gastroenteritis, showing higher severity scores (6.00 vs. 2.94, p = 0.003) compared with those infected with the secondary inoculum. We also observed that infection with the secondary inoculum resulted in longer viral shedding compared with the primary inoculum. Partial sequencing of the SMV genome identified three mutations in both inocula. Understanding the differences between these two SMV inocula is critical for NoV vaccine evaluation and using a less pathogenic inoculum for a vaccine trial will require more participants to meet the target reduction in illness when evaluating the efficacy of candidate vaccines.

Humans↗
PubMed1979

Lack of effect of an interferon inducer, N,N-dihexadecyl-m-xylylenediamine, on rhinovirus challenge in humans.

CP-28,888-27 and placebo nasal sprays were compared in 62 normal volunteers challenged with rhinovirus type 13 or 21 in two randomized, double-blind studies. Half of the subjects received CP-28,888-27 and half received nasal placebo administered at 24, 20, and 16 h before challenge and 4 and 8 h after challenge. In each study, the number of subjects shedding virus in nasal washes, the number developing fourfold or greater serum antibody responses, and the number developing afebrile or febrile upper respiratory tract illness were not significantly different comparing subjects given CP-28,888-27 and those given placebo. Interferon was detected in nasal washes from 5 of 15 volunteers tested in the CP-28,888-27 group compared to 2 of 15 volunteers from the placebo group.

Adult↗
PubMed2025

Advances and challenges in human 3D solid tumor models.

The field of cancer biology and therapeutics has soared in the past several decades with new therapeutic modalities and options for patients, such as chemoradiotherapy, immunotherapy, and combination therapy. This dramatic success in expanding patient options is primarily attributed to the development of various model systems to elucidate drivers of oncogenesis, tumor maturation and evolution, and response to therapeutics. While mouse models have been a workhorse of cancer research, technological progress in ex vivo patient-derived tumor models has afforded more tunable and scrutable systems for patient-predictive platforms and mechanistic study. This review explores the technological innovations in 3D solid tumor models and their applicability to various aspects of cancer biology and identification of therapeutics. Features of the tumor and tumor microenvironment like spatial heterogeneity, multicellular populations and genomic variations are addressed and elaborated through the establishment of new in vitro models. We further address the integration of perfusable vasculature with 3D tumor models and the potentially wide-ranging applications of these more complex platforms in precision medicine and cancer immunotherapy. Finally, we provide an outlook on the future of experimental cancer models for both biological investigation and bench-to-bedside pipeline development.

Journal Article↗
PubMed1979

Biomedical challenges: should "human" be redefined?

The advance of biomedical science is raising fundamental questions about the definition of what it is to be human. Theologians and health care professionals must work together in a communal defense of the Church's profound teachings about the holiness and sacramentality of bodied existence and must relate this teaching to current reproductive technologies.

Attitude to Health↗
PubMed1977

Blocking of histamine release from human basophils in vitro by the ATPase inhibitor, ethacrynic acid.

Ethacrynic acid, a known inhibitor of both Na+--K+ and Mg2+-activated ATPases, effectively inhibits histamine release from antigen-challenged human basophils in vitro. Ouabain, an inhibitor specific for Na+--K+-activated ATPases, shows no effect upon the quantity of histamine released from the antigen-challenged basophils. Ethacrynic acid also effectively inhibits Ca2+--ionophore A23187-induced release, implying it inhibits the Ca2+-dependent secretory stage of the histamine-release process. Inhibition of ATPases and histamine release by ethacrynic acid both require the presence of the olefinic bond in the ethacrynic-acid molecule. Possible utilization of analogues of ethacrynic acid as anti-allergic drugs and as a device to investigate the ATPase system of histamine-releasing cells is suggested.

Adenosine Triphosphatases↗
PubMed2025

BioMedGraphica: An All-in-One Platform for Joint Textual Biomedical Prior Knowledge and Numeric Graph Generation.

Multi-omic data analysis is essential for scientific discovery in precision medicine. However, translating statistical results of omic data analysis into novel scientific hypothesis remains a significant challenge. Human experts must manually review analysis results and generate new hypothesis based on extensive and inter-connected biomedical prior knowledge, which is subjective and not scalable. While large language models (LLMs) can accelerate the discovery, their reasoning improves when grounded in structured, auditable and comprehensive biomedical prior knowledge. Biomedical knowledge, however, is scattered across heterogeneous databases that use diverse and inconsistent nomenclature systems, making it difficult to integrate resources into a unified format for scalable analysis. This fragmentation limits the ability of AI systems to fully leverage biomedical data for scientific discovery. To address these challenges, we developed BioMedGraphica , an all-in-one platform that harmonizes fragmented biomedical resources by integrating 11 entity types and 30 relation types from 43 databases into a unified knowledge graph containing 2,306,921 entities and 27,232,091 relations. In addition, to the best of our knowledge, this is the first work to propose a novel Textual-Numeric Graph (TNG) data-structure for multi-omics data analysis. In TNG, textual information captures prior biological knowledge (e.g., transcription start sites, functions, mechanisms), while numeric values represent quantitative biomedical features, and the integrated relations can help uncover mechanisms. By bridging prior knowledge with user-specific data, TNG is a novel and ideal data-structure for the development of graph foundation models, with the potential to improve prediction performance and interpretability, while also augmenting LLMs by supplying graph-structured mechanistic context to strengthen reasoning. The details for BioMedGraphica code can be accessed by github link: https://github.com/FuhaiLiAiLab/BioMedGraphica and BioMedGraphica knowledge graph data can be downloaded from huggingface dataset: https://huggingface.co/datasets/FuhaiLiAiLab/BioMedGraphica.

biomedical knowledge graph↗
PubMed2026

BioMedGraphica: an all-in-one platform for joint textual biomedical prior knowledge and numeric graph generation.

MOTIVATION: Multiomics data analysis is essential for scientific discovery in precision medicine. However, translating analysis results of omics data analysis into novel scientific hypotheses remains a significant challenge. Human experts must manually review analysis results and generate new hypotheses based on extensive and interconnected biomedical prior knowledge, which is subjective and not scalable. While large language models can accelerate the discovery, their reasoning improves when grounded in structured, auditable, and comprehensive biomedical prior knowledge. However, biomedical knowledge is scattered across heterogeneous databases that use diverse and inconsistent nomenclature systems, making it difficult to integrate resources into a unified format for scalable analysis. This fragmentation limits the ability of artificial intelligence systems to fully leverage biomedical data for scientific discovery. RESULTS: We developed BioMedGraphica, a novel all-in-one platform that harmonizes fragmented biomedical resources by integrating 11 entity types and 30 relation types from 43 databases into a unified textual prior knowledge graph containing 2 306 921 entities and 27 232 091 relations. In addition, we present a novel textual-numeric graph (TNG) data structure concept, where textual information captures prior biological knowledge (e.g. transcription start sites, functions, mechanisms), numeric values represent quantitative biomedical features, and the integrated relations can help uncover mechanisms. By bridging prior knowledge with user-specific data, TNG is a novel and ideal data structure for developing novel graph analysis models. AVAILABILITY AND IMPLEMENTATION: The code is available at: https://github.com/FuhaiLiAiLab/BioMedGraphica and BioMedGraphica knowledge graph database can be downloaded from huggingface dataset: https://huggingface.co/datasets/FuhaiLiAiLab/BioMedGraphica.

Humans↗
PubMed1977

Treatise on aeromedical evacuation: I. Administration and some medical considerations.

Well conceived administrative procedures must be considered the backbone of a good, strong aeromedical evacuation system. These procedures must insure 1) centralized control of patient transportation by aircraft, 2) specialized medical attendants and equipment for inflight medical care, 3) facilities for limited medical care of patients entering, en route in, or leaving the system, and 4) communications with destination and enroute medical facilities concerning patient transportation. There are no absolute contraindications to aeromedical evacuation. However, patients with the following conditions require special consideration. Such conditions are 1) severe anemia, less than 2.5 million RBC/cc or less than 7.0 g hemoglobin/100 ml, 2) respiratory embarrassment, and 3) trapped gas within any of the body cavities. Medical problems in aeromedical evacuation defy resolution only when patient preparation has been improper. When the patient is properly evaluated, then unnecessary, costly, hazardous, and special flights are avoided. Aeromedical evacuation presents no problem so long as one remembers that man is adapted for life at or near sea level and that changes in pressure with increasing altitude affect his physiological processes. This invisible barrier will continue to challenge human ingenuity in the conquest of high altitude.

Adolescent↗
PubMed1979

Studies of ciliated epithelia of the human genital tract. 3: Mucociliary wave activity in organ cultures of human Fallopian tubes challenged with Neisseria gonorrhoeae and gonococcal endotoxin.

Quantative determinations of the mucociliary activity of human Fallopian tube epithelium maintained as organ cultures were performed using a light beam reflex method. In non-infected organ cultures the mucociliary wave (MCW) frequency slowly decreased during the first 54 hours of culture maintenance. In organ cultures experimentally infected with fresh isolates of Neisseria gonorrhoeae producing T1/T2 colonies the MCW frequency either decreased to subnormal values or completely ceased whereas in organ cultured infected with a laboratory-adapted gonococcal strain the MCW frequencies remained within normal range. In organ cultures exposed to gonococcal endotoxin prepared from the laboratory-adapted strain, as well as in cultures in which cell-free filtrates of medium from organ cultures infected with N. gonorrhoeae (producing T1/T2 colonies) were added to the culture medium, the ciliary activity decreased and subsequently ceased. The same phenomenon occurred when organ cultures were challenged with Escherichia coli endotoxin. The ciliostatic effect appeared before any morphological changes in the surface epithelium, including the cilia, were demonstrable by scanning electron microscopy.

Adult↗
PubMed1978

Alterations in the expression of the cytomegalovirus-induced cytopathogenic effect in fibroblasts by aflatoxin B1.

Aflatoxin B1 has been shown both to promote and to alter the expression of the cytopathogenic effect observed when human fibroblasts are challenged with human cytomegalovirus (CMV). Although the cells become round, as is the characteristic effect of this virus on fibroblasts, multinucleate cells are seen to arise from cell fusion within 48 h after virus addition.

Aflatoxins↗