The classical pathway of the complement system is activated by the binding of C1q in the C1 complex to the target activator, including immune complexes. Factor H is regarded as the key downregulatory protein of the complement alternative pathway. However, both C1q and factor H bind to target surfaces via charge distribution patterns. For a few targets, C1q and factor H compete for binding to common or overlapping sites. Factor H, therefore, can effectively regulate the classical pathway activation through such targets, in addition to its previously characterized role in the alternative pathway. Both C1q and factor H are known to recognize foreign or altered-self materials, e.g., bacteria, viruses, and apoptotic/necrotic cells. Clots, formed by the coagulation system, are an example of altered self. Factor H is present abundantly in platelets and is a well-known substrate for FXIIIa. Here, we investigated whether clots activate the complement classical pathway and whether this is regulated by factor H. We show here that both C1q and factor H bind to the fibrin formed in microtiter plates and the fibrin clots formed under in vitro physiological conditions. Both C1q and factor H become covalently bound to fibrin clots, and this is mediated via FXIIIa. We also show that fibrin clots activate the classical pathway of complement, as demonstrated by C4 consumption and membrane attack complex detection assays. Thus, factor H downregulates the activation of the classical pathway induced by fibrin clots. These results elucidate the intricate molecular mechanisms through which the complement and coagulation pathways intersect and have regulatory consequences.

Sigma factors are transcriptional regulators that are part of complex regulatory networks for major cellular processes, as well as for growth phase-dependent regulation and stress response. Actinoplanes sp. SE50/110 is the natural producer of acarbose, an α-glucosidase inhibitor that is used in diabetes type 2 treatment. Acarbose biosynthesis is dependent on growth, making sigma factor engineering a promising tool for metabolic engineering. ACSP50_0507 is a homolog of the developmental and osmotic-stress-regulating Streptomyces coelicolor σHSc. Therefore, the protein encoded by ACSP50_0507 was named σHAs. Here, an Actinoplanes sp. SE50/110 expression strain for the alternative sigma factor gene ACSP50_0507 (sigHAs) achieved a two-fold increased acarbose yield with acarbose production extending into the stationary growth phase. Transcriptome sequencing revealed upregulation of acarbose biosynthesis genes during growth and at the late stationary growth phase. Genes that are transcriptionally activated by σHAs frequently code for secreted or membrane-associated proteins. This is also mirrored by the severely affected cell morphology, with hyperbranching, deformed and compartmentalized hyphae. The dehydrated cell morphology and upregulation of further genes point to a putative involvement in osmotic stress response, similar to its S. coelicolor homolog. The DNA-binding motif of σHAs was determined based on transcriptome sequencing data and shows high motif similarity to that of its homolog. The motif was confirmed by in vitro binding of recombinantly expressed σHAs to the upstream sequence of a strongly upregulated gene. Autoregulation of σHAs was observed, and binding to its own gene promoter region was also confirmed.

The flavonoids in citrus fruits are crucial physiological regulators and natural bioactive products of high pharmaceutical value. Melatonin is a pleiotropic hormone that can regulate plant morphogenesis and stress resistance and alter the accumulation of flavonoids in these processes. However, the direct effect of melatonin on citrus flavonoids remains unclear. In this study, nontargeted metabolomics and transcriptomics were utilized to reveal how exogenous melatonin affects flavonoid biosynthesis in \"Bingtangcheng\" citrus fruits. The melatonin treatment at 0.1 mmol L-1 significantly increased the contents of seven polymethoxylated flavones (PMFs) and up-regulated a series of flavonoid pathway genes, including 4CL (4-coumaroyl CoA ligase), FNS (flavone synthase), and FHs (flavonoid hydroxylases). Meanwhile, CHS (chalcone synthase) was down-regulated, causing a decrease in the content of most flavonoid glycosides. Pearson correlation analysis obtained 21 transcription factors co-expressed with differentially accumulated flavonoids, among which the AP2/EREBP members were the most numerous. Additionally, circadian rhythm and photosynthesis pathways were enriched in the DEG (differentially expressed gene) analysis, suggesting that melatonin might also mediate changes in the flavonoid biosynthesis pathway by affecting the fruit\'s circadian rhythm. These results provide valuable information for further exploration of the molecular mechanisms through which melatonin regulates citrus fruit metabolism.

Global support and standardization of regulation for biosimilars approval owes much of its legacy to the World Health Organization (WHO), since the first guidance by the organization on the matter was released in 2009. Since then, and with over a decade of research, the 2022 revision provides opportunities for time and financial savings to pharmaceutical manufacturers aiming to prove similarity of a potential biosimilar product to some reference product, particularly by clarifying that the use of a non-local reference product as a comparator in certain studies is permissible. This declaration has important implications, particularly in the emerging biological markets of the Middle East and North Africa region, where WHO guidelines have been integral to the regulatory framework of over a dozen countries for more than a decade. This article aims to review the impact of this revision on these countries and relevant policies on non-local comparator usage. Since 2022, this revision has been adopted only in Egypt. Many North African countries are yet to adopt a first draft of the formalized guidance. This analysis revealed that, although many of these countries reference the WHO guidelines, hesitation remains in terms of sourcing comparator products outside the US or European countries. This likely translates to slow regional development and cooperation of functioning, sustainable biosimilars markets. Future studies will be necessary to evaluate the continued development of guidance within these countries and changes in comparator sourcing norms as more time is allowed for their policies to mature and adapt to new standards.

This paper interrogates the depoliticising effects of a seemingly neutral regulatory drive at the heart of the World Health Organization (WHO)\'s promotion of traditional medicine. Emerging at WHO in the late 1960s against a political backdrop of decolonisation and pan-Africanism, traditional medicine has continued to be promoted in subsequent decades, culminating in the latest global Traditional Medicine Strategy (2014 to 2023). Yet WHO\'s promotion and acceptance of traditional medicine have also become increasingly conditional upon its standardisation and regulation - something that appears fundamentally at odds with traditional medicine\'s heterogeneity. Drawing on insights from critical law and science and technology studies, we suggest that such a process at WHO has done more than simply disqualify the toxic and the dangerous. Rather, it has implicitly and explicitly marginalised and excluded those aspects of traditional medicine that deviate from scientific, biomedical ways of seeing, knowing and organising.

BACKGROUND: Software as a medical device (SaMD) has gained the attention of medical device regulatory bodies as the prospects of standalone software for use in diagnositic and therapeutic settings have increased. However, to date, figures related to SaMD have not been made available by regulators, which limits the understanding of how prevalent these devices are and what actions should be taken to regulate them.
OBJECTIVE: The aim of this study is to empirically evaluate the market approvals and clearances related to SaMD and identify adverse incidents related to these devices.
METHODS: Using databases managed by the US medical device regulator, the US Food and Drug Administration (FDA), we identified the counts of SaMD registered with the FDA since 2016 through the use of product codes, mapped the path SaMD takes toward classification, and recorded adverse events.
RESULTS: SaMD does not seem to be registered at a rate dissimilar to that of other medical devices; thus, adverse events for SaMD only comprise a small portion of the total reported number.
CONCLUSIONS: Although SaMD has been identified in the literature as an area of development, our analysis suggests that this growth has been modest. These devices are overwhelmingly classified as moderate to high risk, and they take a very particular path to that classification. The digital revolution in health care is less pronounced when evidence related to SaMD is considered. In general, the addition of SaMD to the medical device market seems to mimic that of other medical devices.

BACKGROUND: Assisted dying (AD) has been legalised in a small but growing number of jurisdictions globally, including Canada and Australia. Early research in both countries demonstrates that, in response to access barriers, patients and caregivers take action to influence their individual experience of AD, as well as AD systems more widely. This study analyses how patients and caregivers suggest other decision-makers in AD systems should address identified issues.
METHODS: We conducted semistructured, qualitative interviews with patients and caregivers seeking AD in Victoria (Australia) and three Canadian provinces (British Columbia, Ontario and Nova Scotia). Data were analysed using reflexive thematic analysis and codebook template analysis.
RESULTS: Sixty interviews were conducted with 67 participants (65 caregivers, 2 patients). In Victoria, this involved 28 interviews with 33 participants (32 caregivers, 1 patient) about 28 patient experiences. In Canada, this involved 32 interviews with 34 participants (33 caregivers, 1 patient) about 33 patient experiences. We generated six themes, corresponding to six overarching suggestions by patients and caregivers to address identified system issues: (1) improved content and dissemination of information about AD; (2) proactively develop policies and procedures about AD provision; (3) address institutional objection via top-down action; (4) proactively develop grief resources and peer support mechanisms; (5) amend laws to address legal barriers; and (6) engage with and act on patient and caregiver feedback about experiences.
CONCLUSIONS: AD systems should monitor and respond to suggestions from patients and caregivers with firsthand experience of AD systems, who are uniquely placed to identify issues and suggestions for improvement. To date, Canada has responded comparatively well to address identified issues, whereas the Victorian government has signalled there are no plans to amend laws to address identified access barriers. This may result in patients and caregivers continuing to take on the burdens of acting to address identified issues.
UNASSIGNED: Patients and caregivers are central to this research. We interviewed patients and caregivers about their experiences of AD, and the article focuses on their suggestions for addressing identified barriers within AD systems. Patient interest groups in Australia and Canada also supported our recruitment process.

Inflammasomes contribute to colorectal cancer signaling by primarily inducing inflammation in the surrounding tumor microenvironment. Its role in inflammation is receiving increasing attention, as inflammation has a protumor effect in addition to inducing tissue damage. The inflammasome\'s function is complex and controlled by several layers of regulation. Epigenetic processes impact the functioning or manifestation of genes that are involved in the control of inflammasomes or the subsequent signaling cascades. Researchers have intensively studied the significance of epigenetic mechanisms in regulation, as they encompass several potential therapeutic targets. The regulatory interactions between the inflammasome and autophagy are intricate, exhibiting both advantageous and harmful consequences. The regulatory aspects between the two entities also encompass several therapeutic targets. The relationship between the activation of the inflammasome, autophagy, and epigenetic alterations in CRC is complex and involves several interrelated pathways. This article provides a brief summary of the newest studies on how epigenetics and autophagy control the inflammasome, with a special focus on their role in colorectal cancer. Based on the latest findings, we also provide an overview of the latest therapeutic ideas for this complex network.

Vibrio fluvialis is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and food safety worldwide. The arginine deiminase (ADI) pathway plays an important role in bacterial environmental adaptation and pathogenicity. However, the biological functions and regulatory mechanisms of the pathway in V. fluvialis remain unclear. In this study, we demonstrate that L-arginine upregulates the expression of the ADI gene cluster and promotes the growth of V. fluvialis. The ADI gene cluster, which we proved to be comprised of two operons, arcD and arcACB, significantly enhances the survival of V. fluvialis in acidic environments both in vitro (in culture medium and in macrophage) and in vivo (in mice). The mRNA level and reporter gene fusion analyses revealed that ArgR, a transcriptional factor, is necessary for the activation of both arcD and arcACB transcriptions. Bioinformatic analysis predicted the existence of multiple potential ArgR binding sites at the arcD and arcACB promoter regions that were further confirmed by electrophoretic mobility shift assay, DNase I footprinting, or point mutation analyses. Together, our study provides insights into the important role of the ArgR-ADI pathway in the survival of V. fluvialis under acidic conditions and the detailed molecular mechanism. These findings will deepen our understanding of how environmental changes and gene expression interact to facilitate bacterial adaptations and virulence.

3D printing has been adopted into routine use for certain medical applications, but more widespread usage has been hindered by, among other things, unclear legislation. We performed an analysis, using legal doctrinal study and legal informatics, of relevant EU legislation and case law in four issues relevant to medical 3D printing (excluding bioprinting or pharmacoprinting): pre-market approval, post-market liability, intellectual property rights, and data protection. Several gaps and uncertainties in the current legislation and interpretations were identified. In particular, we regard the current EU regulatory framework to be quite limiting and inflexible, exemplifying a cautionary approach common in EU law. Though the need to establish high safety standards in order to protect patients as a disadvantaged population is understood, both legal uncertainties and overregulation are seen as harmful to innovation. Hence, more adaptive legislation is called for to ensure continuous innovation efforts and enhanced patient outcomes.