Although orthopoxviruses (OPXV) are known to encode a majority of the genes required for replication in host cells, genome-wide genetic screens have revealed that several host pathways are ...indispensable for OPXV infection. Through a haploid genetic screen, we previously identified several host genes required for monkeypox virus (MPXV) infection, including the individual genes that form the conserved oligomeric Golgi (COG) complex. The COG complex is an eight-protein (COG1-COG8) vesicle tethering complex important for regulating membrane trafficking, glycosylation enzymes, and maintaining Golgi structure. In this study, we investigated the role of the COG complex in OPXV infection using cell lines with individual COG gene knockout (KO) mutations. COG KO cells infected with MPXV and vaccinia virus (VACV) produced small plaques and a lower virus yield compared to wild type (WT) cells. In cells where the KO phenotype was reversed using a rescue plasmid, the size of virus plaques increased demonstrating a direct link between the decrease in viral spread and the KO of COG genes. KO cells infected with VACV displayed lower levels of viral fusion and entry compared to WT suggesting that the COG complex is important for early events in OPXV infection. Additionally, fewer actin tails were observed in VACV-infected KO cells compared to WT. Since COG complex proteins are required for cellular trafficking of glycosylated membrane proteins, the disruption of this process due to lack of individual COG complex proteins may potentially impair the virus-cell interactions required for viral entry and egress. These data validate that the COG complex previously identified in our genetic screens plays a role in OPXV infection.
Necrotizing enterocolitis (NEC) remains a leading cause of morbidity and mortality in preterm infants. Although its pathogenesis is poorly understood, inappropriate apoptosis of the mucosal epithelia ...has been implicated. Recent clinical trials have shown that probiotics may reduce the incidence of NEC, and probiotics have been shown to suppress intestinal epithelial apoptosis in cultured cells. However, little is known about their mechanism of action in the developing intestine in vivo. Here, we confirm that the probiotic Lactobacillus rhamnosus GG (LGG) reduces chemically induced intestinal epithelial apoptosis in vitro. Furthermore, we report for the first time that LGG administered orally to live animals can reduce chemically induced epithelial apoptosis ex vivo, as measured by staining for active caspase 3 and terminal deoxynucleotidyltransferase. Using cDNA microarray analysis from the intestine of live, orally inoculated mice, we show that LGG up-regulates a battery of genes with known and likely cytoprotective effects. These studies indicate that probiotics such as LGG may augment intestinal host defenses in the developing intestine by stimulating antiapoptotic and cytoprotective responses. Because apoptosis may be a precursor to NEC, understanding the mechanism behind probiotic modulation of apoptotic pathways may allow for development of more specifically targeted therapies or preventive strategies in the future.
The human enteric flora plays a significant role in intestinal health and disease. Populations of enteric bacteria can inhibit the NF-kappaB pathway by blockade of IkappaB-alpha ubiquitination, a ...process catalyzed by the E3-SCF(beta-TrCP) ubiquitin ligase. The activity of this ubiquitin ligase is regulated via covalent modification of the Cullin-1 subunit by the ubiquitin-like protein NEDD8. We previously reported that interaction of viable commensal bacteria with mammalian intestinal epithelial cells resulted in a rapid and reversible generation of reactive oxygen species (ROS) that modulated neddylation of Cullin-1 and resulted in suppressive effects on the NF-kappaB pathway. Herein, we demonstrate that butyrate and other short chain fatty acids supplemented to model human intestinal epithelia in vitro and human tissue ex vivo results in loss of neddylated Cul-1 and show that physiological concentrations of butyrate modulate the ubiquitination and degradation of a target of the E3- SCF(beta-TrCP) ubiquitin ligase, the NF-kappaB inhibitor IkappaB-alpha. Mechanistically, we show that physiological concentrations of butyrate induces reactive oxygen species that transiently alters the intracellular redox balance and results in inactivation of the NEDD8-conjugating enzyme Ubc12 in a manner similar to effects mediated by viable bacteria. Because the normal flora produces significant amounts of butyrate and other short chain fatty acids, these data provide a functional link between a natural product of the intestinal normal flora and important epithelial inflammatory and proliferative signaling pathways.
Orthopoxviruses (OPXVs) are an increasing threat to human health due to the growing population of OPXV-naive individuals after the discontinuation of routine smallpox vaccination. Antiviral drugs ...that are effective as postexposure treatments against variola virus (the causative agent of smallpox) or other OPXVs are critical in the event of an OPXV outbreak or exposure. The only US Food and Drug Administration-approved drug to treat smallpox, Tecovirimat (ST-246), exerts its antiviral effect by inhibiting extracellular virus (EV) formation, thereby preventing cell-cell and long-distance spread. We and others have previously demonstrated that host Golgi-associated retrograde proteins play an important role in monkeypox virus (MPXV) and vaccinia virus (VACV) EV formation. Inhibition of the retrograde pathway by small molecules such as Retro-2 has been shown to decrease VACV infection
and to a lesser extent
. To identify more potent inhibitors of the retrograde pathway, we screened a large panel of compounds containing a benzodiazepine scaffold like that of Retro-1, against VACV infection. We found that a subset of these compounds displayed better anti-VACV activity, causing a reduction in EV particle formation and viral spread compared to Retro-1. PA104 emerged as the most potent analog, inhibiting 90% viral spread at 1.3 μM with a high selectivity index. In addition, PA104 strongly inhibited two distinct ST-246-resistant viruses, demonstrating its potential benefit for use in combination therapy with ST-246. These data and further characterizations of the specific protein targets and
efficacy of PA104 may have important implications for the design of effective antivirals against OPXV.
We report the fabrication and characterization of a two-dimensional (2D) silicon photonic crystal biosensor consisting of waveguides and cavity-type and defect-type resonators for enhancing the ...interactions between light and biomaterials. Sensitivity was measured using sucrose solution and the sensor showed the highest sensitivity 1570 nm/RIU (refractive index unit) ever reported. We also investigated cavity size effects on resonance wavelength shift, and we observed that a large cavity exhibits a greater resonance wavelength shift. The fabricated sensor has shown a high Q of ∼105 in water and a device figure of merit of 1.2 × 105, which represent the improvements of the device performance over other photonic-crystal-based sensors.
Background
Artificial intelligence (AI)-enabled applications are increasingly being used in providing healthcare services, such as medical imaging support. Sufficient and appropriate education for ...medical imaging professionals is required for successful AI adoption. Although, currently, there are AI training programmes for radiologists, formal AI education for radiographers is lacking. Therefore, this study aimed to evaluate and discuss a postgraduate-level module on AI developed in the UK for radiographers.
Methodology
A participatory action research methodology was applied, with participants recruited from the first cohort of students enrolled in this module and faculty members. Data were collected using online, semi-structured, individual interviews and focus group discussions. Textual data were processed using data-driven thematic analysis.
Results
Seven students and six faculty members participated in this evaluation. Results can be summarised in the following four themes: a. participants’ professional and educational backgrounds influenced their experiences, b. participants found the learning experience meaningful concerning module design, organisation, and pedagogical approaches, c. some module design and delivery aspects were identified as barriers to learning, and d. participants suggested how the ideal AI course could look like based on their experiences.
Conclusions
The findings of our work show that an AI module can assist educators/academics in developing similar AI education provisions for radiographers and other medical imaging and radiation sciences professionals. A blended learning delivery format, combined with customisable and contextualised content, using an interprofessional faculty approach is recommended for future similar courses.
Key points
A novel postgraduate module on AI for radiographers was developed and evaluated.
Blended-learning delivery, customisable and contextualised course content, and interprofessional faculty are the ways forward for an ideal AI course for radiographers.
Future courses could use this approach to develop their own AI training.
We demonstrated a two-dimensional double-cavity silicon photonic-crystal resonator based neighboring hole radius modulation. By theoretical and experimental analyses, we confirmed that the quality ...factor (Q-factor) increases at a certain neighboring hole radius. Experimentally, we showed Q-factors of (1.93-2.02) × 105. Moreover, by using sucrose solution, we measured a sensitivity of 1571 nm/RIU (refractive index unit), which is the highest sensitivity ever reported for such a two-dimensional photonic-crystal-based resonator type device. We reported the detection limit (DL) of the refractive index change of (4.15-4.34) × 10−6 RIU, which is one of the best in previous reports.
In this paper, we describe the mechanism and solution for dominating temperature effects on refractive-index-based Si optical resonator sensors such as ring resonator and photonic crystal resonator ...sensors. The temperature change affects the silicon refractive index and also the resonator mechanical shape. As a result, it is reported that the refractive index change is marked, whereas the mechanical deformation effect is negligible. We also demonstrated that the differential operation is effective for suppressing the temperature effect for Si ring resonator sensors.
Objectives
To conduct a qualitative study, guided by the principles of community-based participatory research, with the following objectives: (1) to provide a conceptual framework describing the ...drivers of son preference; (2) to understand experiences of son preference among Punjabi-Canadians and (3) with this understanding, identify and co-design an appropriate educational tool.
Design, setting, participants, methods
Qualitative study consisting of four bilingual (Punjabi and English) focus group discussions with 11 mothers, 4 fathers and 17 grandmothers in Toronto and Brampton, Canada. Participants were queried about experiences and perspectives related to reproductive decision-making, gender equity and son preference, and for appropriate approaches to reducing inequities. Transcripts were simultaneously translated and written in English and thematic analysis was conducted. An infoposter was identified as a feasible educational tool and was co-designed by researchers and community partners.
Results
Participants identified patrilocality (ie, married sons reside with parents, married daughters with in-laws) and patrilineality (ie, sons inherit assets, daughters’ husband receives a dowry) as structural precursors to proximal drivers (ie, old-age security) of son preference. Mothers’ and grandmothers’ value to their families depended strongly on having a son but did not guarantee security. Pressures (ie, internalised discrimination, reproductive coercion) to conceive a son were common after the birth of at least one daughter in the absence of sons. Participants did not know anyone who had a sex selective abortion in Canada; however, traditional sex selection methods (eg, herbal medicines) were mentioned. Our co-designed infoposter entitled ‘Truths About Son Preference’ addressed three misconceptions identified in discussions.
Conclusion
This study may be useful to health and social care providers in providing structurally competent and culturally humble counselling and care, particularly after the birth of daughters in the absence of sons. Community engagement is necessary for future intervention development.
In raspberry (Rubus idaeus), development of fruit color and flavor are critically dependent on products of the phenylpro-panoid pathway. To determine how these metabolic functions are integrated with ...the fruit ripening program, we are examining the properties and expression of key genes in the pathway. Here, we report that L- phenylalanine ammonia-lyase (PAL) is encoded in raspberry by a family of two genes (RiPAL1 and RiPAL2). RiPAL1 shares 88% amino acid sequence similarity to RiPAL2, but phylogenetic analysis places RiPAL1 and RiPAL2 in different clusters within the plant PAL gene family. The spatial and temporal expression patterns of the two genes were investigated in various vegetative and floral tissues using the reverse transcriptase competitor polymerase chain reaction assay. Although expression of both genes was detected in all tissues examined, RiPAL1 was associated with early fruit ripening events, whereas expression of RiPAL2 correlated more with later stages of flower and fruit development. Determination of the absolute levels of the two transcripts in various tissues showed that RiPAL1 transcripts were 3- to 10-fold more abundant than those of RiPAL2 in leaves, shoots, roots, young fruits, and ripe fruits. The two RiPAL genes therefore appear to be controlled by different regulatory mechanisms.
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