Measurement of Photon Statistics with Live Photoreceptor Cells

We analyzed the electrophysiological response of an isolated rod photoreceptor of Xenopus laevis under stimulation by coherent and pseudo-thermal light sources. Using the suction electrode technique for single cell recordings and a fiber optics setup for light delivery allowed measurements of the major statistical characteristics of the rod response. The results indicate differences in average responses of rod cells to coherent and pseudo-thermal light of the same intensity and also differences in signal-to-noise ratios and second order intensity correlation functions. These findings should be relevant for interdisciplinary studies seeking applications of quantum optics in biology.Comment: 6 pages, 7 figure

Exercise medicine for cancer cachexia: Targeted exercise to counteract mechanisms and treatment side-effects

Purpose: Cancer-induced muscle wasting (i.e., cancer cachexia, CC) is a common and devastating syndrome that results in the death of more than 1 in 5 patients. Although primarily a result of elevated inflammation, there are multiple mechanisms that complement and amplify one another. Research on the use of exercise to manage CC is still limited, while exercise for CC management has been recently discouraged. Moreover, there is a lack of understanding that exercise is not a single medicine, but mode, type, dosage, and timing (exercise prescription) have distinct health outcomes. The purpose of this review was to examine the effects of these modes and subtypes to identify the most optimal form and dosage of exercise therapy specific to each underlying mechanism of CC. Methods: The relevant literatures from MEDLINE and Scopus databases were examined. Results: Exercise can counteract the most prominent mechanisms and signs of CC including muscle wasting, increased protein turnover, systemic inflammation, reduced appetite and anorexia, increased energy expenditure and fat wasting, insulin resistance, metabolic dysregulation, gut dysbiosis, hypogonadism, impaired oxidative capacity, mitochondrial dysfunction, and cancer treatments side-effects. There are different modes of exercise, and each mode has different sub-types that induce vastly diverse changes when performed over multiple sessions. Choosing suboptimal exercise modes, types, or dosages can be counterproductive and could further contribute to the mechanisms of CC without impacting muscle growth. Conclusion: Available evidence shows that patients with CC can safely undertake higher-intensity resistance exercise programs, and benefit from increases in body mass and muscle mass

Anxiety, depression and comorbid anxiety and depression: risk factors and outcome over two years

Background: This study aimed to determine: (1) the prevalence of depression, anxiety, and depression associated with anxiety (DA); (2) the risk factor profile of depression, anxiety, and DA; (3) the course of depression, anxiety, and DA over 24 months. Methods: Two-year longitudinal study of 20,036 adults aged 60+ years. We used the Patient Health Questionnaire and the Hospital Anxiety and Depression Scale anxiety subscale to establish the presence of depression and anxiety, and standard procedures to collect demographic, lifestyle, psychosocial, and clinical data. Results: The prevalence of anxiety, depression, and DA was 4.7%, 1.4%, and 1.8%. About 57% of depression cases showed evidence of comorbid anxiety, while only 28% of those with clinically significant anxiety had concurrent depression. There was not only an overlap in the distribution of risk factors in these diagnostic groups but also differences. We found that 31%, 23%, and 35% of older adults with anxiety, depression, and DA showed persistence of symptoms after two years. Repeated anxiety was more common in women and repeated depression in men. Socioeconomic stressors were common in repeated DA. Conclusions: Clinically significant anxiety and depression are distinct conditions that frequently coexist in later life; when they appear together, older adults endure a more chronic course of illness

Novel STMN2 Variant Linked to Amyotrophic Lateral Sclerosis Risk and Clinical Phenotype.

OBJECTIVE: There is a critical need to establish genetic markers that explain the complex phenotypes and pathogenicity of ALS. This study identified a polymorphism in the Stathmin-2 gene and investigated its association with sporadic ALS (sALS) disease risk, age-of onset and survival duration. METHODS: The candidate CA repeat was systematically analyzed using PCR, Sanger sequencing and high throughput capillary separation for genotyping. Stathmin-2 expression was investigated using RT-PCR in patient olfactory neurosphere-derived (ONS) cells and RNA sequencing in laser-captured spinal motor neurons. RESULTS: In a case-control analysis of a combined North American sALS cohort (n = 321) and population control group (n = 332), long/long CA genotypes were significantly associated with disease risk (p = 0.042), and most strongly when one allele was a 24 CA repeat (p = 0.0023). In addition, longer CA allele length was associated with earlier age-of-onset (p = 0.039), and shorter survival duration in bulbar-onset cases (p = 0.006). In an Australian longitudinal sALS cohort (n = 67), ALS functional rating scale scores were significantly lower in carriers of the long/long genotype (p = 0.034). Stathmin-2 mRNA expression was reduced in sporadic patient ONS cells. Additionally, sALS patients and controls exhibited variable expression of Stathmin-2 mRNA according to CA genotype in laser-captured spinal motor neurons. CONCLUSIONS: We report a novel non-coding CA repeat in Stathmin-2 which is associated with sALS disease risk and has disease modifying effects. The potential value of this variant as a disease marker and tool for cohort enrichment in clinical trials warrants further investigation

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Complement Activation-Independent Attenuation of SARS-CoV-2 Infection by C1q and C4b-Binding Protein

The complement system is a key component of the innate immune response to viruses and proinflammatory events. Exaggerated complement activation has been attributed to the induction of a cytokine storm in severe SARS-CoV-2 infection. However, there is also an argument for the protective role of complement proteins, given their local synthesis or activation at the site of viral infection. This study investigated the complement activation-independent role of C1q and C4b-binding protein (C4BP) against SARS-CoV-2 infection. The interactions of C1q, its recombinant globular heads, and C4BP with the SARS-CoV-2 spike and receptor binding domain (RBD) were examined using direct ELISA. In addition, RT-qPCR was used to evaluate the modulatory effect of these complement proteins on the SARS-CoV-2-mediated immune response. Cell binding and luciferase-based viral entry assays were utilised to assess the effects of C1q, its recombinant globular heads, and C4BP on SARS-CoV-2 cell entry. C1q and C4BP bound directly to SARS-CoV-2 pseudotype particles via the RBD domain of the spike protein. C1q via its globular heads and C4BP were found to reduce binding as well as viral transduction of SARS-CoV-2 spike protein expressing lentiviral pseudotypes into transfected A549 cells expressing human ACE2 and TMPRSS2. Furthermore, the treatment of the SARS-CoV-2 spike, envelope, nucleoprotein, and membrane protein expressing alphaviral pseudotypes with C1q, its recombinant globular heads, or C4BP triggered a reduction in mRNA levels of proinflammatory cytokines and chemokines such as IL-1β, IL-8, IL-6, TNF-α, IFN-α, and RANTES (as well as NF-κB) in A549 cells expressing human ACE2 and TMPRSS2. In addition, C1q and C4BP treatment also reduced SARS-CoV-2 pseudotype infection-mediated NF-κB activation in A549 cells expressing human ACE2 and TMPRSS2. C1q and C4BP are synthesised primarily by hepatocytes; however, they are also produced by macrophages, and alveolar type II cells, respectively, locally at the pulmonary site. These findings support the notion that the locally produced C1q and C4BP can be protective against SARS-CoV-2 infection in a complement activation-independent manner, offering immune resistance by inhibiting virus binding to target host cells and attenuating the infection-associated inflammatory response

Examining the effectiveness of different dental recall strategies on maintenance of optimum oral health:the INTERVAL dental recalls randomised controlled trial

Objective: To compare the clinical effectiveness of different frequencies of dental recall over a four-year period.Design: A multi-centre, parallel-group, randomised controlled trial with blinded clinical outcome assessment. Participants were randomised to receive a dental check-up at six-monthly, 24-monthly or risk-based recall intervals. A two-strata trial design was used, with participants randomised within the 24-month stratum if the recruiting dentist considered them clinically suitable. Participants ineligible for 24-month recall were randomised to a risk-based or six-month recall interval.Setting: UK primary dental care.Participants: Practices providing NHS care and adults who had received regular dental check-ups.Main outcome measures: The percentage of sites with gingival bleeding on probing, oral health-related quality of life (OHRQoL), cost-effectiveness.Results: In total, 2,372 participants were recruited from 51 dental practices. Of those, 648 were eligible for the 24-month recall stratum and 1,724 participants were ineligible. There was no evidence of a significant difference in the mean percentage of sites with gingival bleeding on probing between intervention arms in any comparison. For those eligible for 24-month recall stratum: the 24-month versus six-month group had an adjusted mean difference of -0.91%, 95% CI (-5.02%, 3.20%); the 24-month group versus risk-based group had an adjusted mean difference of 0.07%, 95% CI (-3.99%, 4.12%). For the overall sample, the risk-based versus six-month adjusted mean difference was 0.78%, 95% CI (-1.17%, 2.72%). There was no evidence of a difference in OHRQoL (0-56 scale, higher score for poorer OHRQoL) between intervention arms in any comparison. For the overall sample, the risk-based versus six-month effect size was -0.35, 95% CI (-1.02, 0.32). There was no evidence of a clinically meaningful difference between the groups in any comparison in either eligibility stratum for any of the secondary clinical or patient-reported outcomes.Conclusion: Over a four-year period, we found no evidence of a difference in oral health for participants allocated to a six-month or a risk-based recall interval, nor between a 24-month, six-month or risk-based recall interval for participants eligible for a 24-month recall. However, patients greatly value and are willing to pay for frequent dental check-ups.</p

Recruiting and retaining GPs and patients in intervention studies: the DEPS-GP project as a case study

Background: Recruiting and retaining GPs for research can prove difficult, and may result in sub-optimal patient participation where GPs are required to recruit patients. Low participation rates may affect the validity of research. This paper describes a multi-faceted approach to maximise participation of GPs and their patients in intervention studies, using an Australian randomised controlled trial of a depression/suicidality management intervention as a case study. The paper aims to outline experiences that may be of interest to others considering engaging GPs and/or their patients in primary care studies. Methods: A case study approach is used to describe strategies for: (a) recruiting GPs; (b) encouraging GPs to recruit patients to complete a postal questionnaire; and (c) encouraging GPs to recruit patients as part of a practice audit. Participant retention strategies are discussed in light of reasons for withdrawal. Results: The strategies described, led to the recruitment of a higher than expected number of GPs (n = 772). Three hundred and eighty three GPs (49.6%) followed through with the intent to participate by sending out a total of 77,820 postal questionnaires, 22,251 (28.6%) of which were returned. Three hundred and three GPs (37.0%) participated in the practice audit, which aimed to recruit 20 patients per participating GP (i.e., a total of 6,060 older adults). In total, 5,143 patients (84.9%) were represented in the audit. Conclusion: Inexpensive methods were chosen to identify and recruit GPs; these relied on an existing database, minor promotion and a letter of invitation. Anecdotally, participating GPs agreed to be involved because they had an interest in the topic, believed the study would not impinge too greatly on their time, and appreciated the professional recognition afforded by the Continuing Professional Development (CPD) points associated with study participation. The study team established a strong rapport with GPs and their reception staff, offered clear instructions, and were as flexible and helpful as possible to retain GP participants. Nonetheless, we experienced attrition due to GPs' competing demands, eligibility, personnel issues and the perceived impact of the study on patients. A summary of effective and ineffective methods for recruitment and retention is provided.Michelle K Williamson, Jane Pirkis, Jon J Pfaff, Orla Tyson, Moira Sim, Ngaire Kerse, Nicola T Lautenschlager, Nigel P Stocks and Osvaldo P Almeid

C4b Binding Protein Acts as an Innate Immune Effector Against Influenza A Virus

C4b Binding Protein (C4BP) is a major fluid phase inhibitor of the classical and lectin pathways of the complement system. Complement inhibition is achieved by binding to and restricting the role of activated complement component C4b. C4BP functions as a co-factor for factor I in proteolytic inactivation of both soluble and cell surface-bound C4b, thus restricting the formation of the C3-convertase, C4b2a. C4BP also accelerates the natural decay/dissociation of the C3 convertase. This makes C4BP a prime target for exploitation by pathogens to escape complement attack, as seen in Streptococcus pyogenes or Flavivirus. Here, we examined whether C4BP can act on its own in a complement independent manner, against pathogens. C4BP bound H1N1 and H3N2 subtypes of Influenza A Virus (IAV) most likely via multiple sites in Complement Control Protein (CCP) 1-2, 4-5, and 7-8 domains of its α-chain. In addition, C4BP CCP1-2 bound H3N2 better than H1N1. C4BP bound three IAV envelope proteins: Haemagglutinin (~70 kDa), Neuraminidase (~55 kDa), and Matrix protein 1 (~25kDa). C4BP suppressed H1N1 subtype infection into the lung epithelial cell line, A549, while it promoted infection by H3N2 subtype. C4BP restricted viral entry for H1N1 but had the opposite effect on H3N2, as evident from experiments using pseudo-typed viral particles. C4BP downregulated mRNA levels of pro-inflammatory IFN-α, IL-12, and NFκB in the case of H1N1, while it promoted a pro-inflammatory immune response by upregulating IFN- α, TNF-α, RANTES, and IL-6 in the case of H3N2. We conclude that C4BP differentially modulates the efficacy of IAV entry, and hence, replication in a target cell in a strain-dependent manner, and acts as an entry inhibitor for H1N1. Thus, CCP containing complement proteins such as factor H and C4BP may have additional defense roles against IAV that do not rely on the regulation of complement activation