Clinical potential of human amniotic fluid stem cells.

OBJECTIVES: To determine whether amniotic fluid derived stem cells maintain their stem cell characteristics (a) after processing by a licensed cell therapy center and (b) after the cells undergo simulated clinical application. METHODS: Amniotic fluid was collected by laparotomy - a small uterine incision was made at proposed site for delivery and a sterile catheter inserted to collect fluid into a sterile bag. After flow stopped the catheter was withdrawn, the cesarean completed and the collected fluid delivered to the cell therapy center for processing and cryostorage. A clinical setting was simulated where amniotic fluid cells received from cell therapy center were thawed at room temperature for a maximum of 3 h and passed through a clinical cell delivery device to monitor cell viability. The cells were examined for viability, stability, growth, differentiation, and markers of stemness. RESULTS: Amniotic fluid stem cells processed from a clinical cell therapy center behave similarly to amniotic fluid stem cells processed in a research laboratory with respects to viability, stability, growth, differentiation and maintain markers of stemness. There were differences due to heterogeneity of samples which were not methodological. Growth in cell culture and differentiation were satisfactory. Simulation of treating the cells in a clinical environment show a general stability in viability of amniotic fluid cells at room temperature for 3 h minimum and when passed through a clinically approved delivery device. CONCLUSIONS: The data indicate human amniotic fluid processed in a clinical facility could be used therapeutically if proven to be safe.

The impact of seizure frequency on quality of life in patients with Lennox-Gastaut syndrome or Dravet syndrome.

OBJECTIVES: Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) are rare treatment-resistant epileptic encephalopathies with limited data describing the relationship between seizures and quality of life (QoL). The objective of this cross-sectional pilot study was to assess the impact on QoL of seizures and seizure-free days for the generation of utility values. METHODS: Surveys were conducted in the UK and France, whereby patients and/or caregivers of patients with LGS, DS, or other epilepsies were asked to score health state vignettes for a hypothetical patient with LGS or DS. Respondents evaluated QoL for health states based on the number of seizures and seizure-free days per month, using a visual analog scale (VAS). Visual analog scale scores were converted to the 0-1 scale as a proxy estimate for utility values. Surveys were pilot tested and respondents were recruited from October 2018 to August 2019. RESULTS: Patient respondents were mainly treatment-responsive (n = 43/55) whereas caregiver respondents mainly cared for patients with treatment-resistant epilepsy (n = 38/43). Most respondents and patients were aged ≥18 years. Results from LGS and DS surveys in the UK (n = 58) and France (n = 40) suggested that health states with fewer seizures and more seizure-free days had higher QoL scores for hypothetical patients. For DS, QoL scores for patient health states ranged from 0.20 (32 convulsive seizures and 4 seizure-free days/month, UK) to 0.92 (seizure-free, France). For LGS, scores ranged from 0.14 (130 drop seizures and 1 seizure-free day/month, France) to 0.83 (seizure-free, UK). In all surveys, seizure-free days had a greater impact on QoL than seizure frequency (P < 0.001). CONCLUSIONS: Fewer seizures and additional seizure-free days improved QoL in patients with LGS or DS; seizure-free days had the greatest impact on QoL.

Impact of childhood Dravet syndrome on care givers of patients with DS, a major impact on mothers.

BACKGROUND: The aim of this study was to understand the impact of Dravet syndrome (DS) on patients with Dravet syndrome and their families, with a focus on the social and economic impact on both mothers and fathers. METHODS: A French language on-line survey was distributed (October 2014-January 2015) for completion by caregivers of patients aged <18 years with DS. The survey was hosted on the French Dravet Syndrome Alliance website, and the survey link was provided to patients and caregivers during clinics at the Necker Hospital (Paris, France). RESULTS: Survey responses were available for 91 patients (median age 7.6 years; 81.6% SCN1A mutation positive). Total seizure frequency was >2 per week for 16.1% of patients, 1-8 per month for 55.2% and < 1 per month for 28.7%; tonic-clonic and myoclonic were the most frequent seizure types. Patients showed various degrees of intellectual disability and DS had a high impact on concentration and school learning in 70.1% and 80.5%. In addition, patients showed appetite disorders in 73.6%, sleep disorders in 72.4% and behavior disorders in 62.1%. Most parents were married (80.5%) with higher rates than the French general population (53.5%). Educational achievement and socio-professional categories for the parents were higher than observed in the French general population, while monthly net income was similar. Preparation of medication was generally done by the mother and father (46.0% of patients) or the mother only (37.9%). Most caregivers reported very low or no difficulty with treatment preparation and low or no risk of error. Parents typically spent <30 min per day on treatment preparation and administration and around 4 h per week for attending therapy appointments. Although most patients and parents were perceived to have good general health, mothers had a worse perception of their own general health than fathers. Compared with fathers, mothers reported a greater impact of caring for a child with DS on their social life, relationships with family and friends, time and energy, and professional life. CONCLUSION: Families caring for a child with DS experience considerable social and economic impact, with an apparent greater burden of care on the mother than the father.

Treatment patterns and real world clinical outcomes in ER+/HER2- post-menopausal metastatic breast cancer patients in the United States.

BACKGROUND: With several new therapies becoming available, treatment of metastatic breast cancer (mBC) is evolving. The objective of this study is to describe patient characteristics, treatment patterns and real-world clinical outcomes in post-menopausal women with ER+, HER2- mBC and to obtain insight into patient outcomes and potential unmet needs with current therapies. METHODS: The current study is a physician survey followed by a retrospective chart review of patient medical records by physicians in the US between March and April 2015. One hundred three physicians were asked to complete an online survey aiming to understand their satisfaction and expectations with current available treatments and potential areas of unmet need for mBC patients. Medical records from 178 females were extracted for the chart review. Using these data from medical records, patient characteristics and treatment patterns were analyzed descriptively. Time to progression (TTP) on first line, and progression-free survival (PFS) on second and third line of therapy were analyzed using the Kaplan-Meier method. RESULTS: Sixty-seven percent (n = 119) of patients had metastatic disease at initial diagnosis of breast cancer. Mean age at chart data extraction was 65.8 (SD: 9.4) years. Aromatase inhibitors (AIs) were prescribed for 58% and around 13% of patients in first line and second line, respectively. Chemotherapy was prescribed to 14% in first line and 31% in second line. Median TTP on first line therapy was 12 months for patients receiving AIs as compared to 7.9 months for patients receiving chemotherapy. Across all treatment lines, bone pain and fatigue were reported as the main symptoms associated with disease progression which had an impact on patient quality of life. Physicians expressed that prolonging life was deemed the most important treatment goal, followed by preservation or improvement of quality of life. CONCLUSION: In this study the majority of patients received endocrine therapy as first line treatment and current therapies still resulted in a short time to progression in first line. Results from the chart review and the physician survey highlight a quantitative unmet need for more effective treatments which delay disease progression and improve survival outcomes while maintaining quality of life.

Georgia Primary Care Providers' Knowledge of Hereditary Breast and Ovarian Cancer Syndrome.

Hereditary breast and ovarian cancer syndrome (HBOC) is an inherited condition associated with mutations in the BRCA1 or BRCA2 (BRCA) genes. Identification of individuals with HBOC requires that primary care providers understand the genetic principles required to appropriately collect family history and refer individuals for genetic evaluation. A survey was developed and administered to primary care providers in Georgia to assess their existing knowledge of HBOC and direct targeted educational efforts.We found that Georgia providers demonstrate some knowledge of basic genetic principles but were unable to consistently identify individuals at risk for HBOC. Knowledge deficits included lack of understanding of inheritance patterns and failure to recognize the significance of ovarian cancer history. Strategies for improving identification of patients with HBOC include increasing provider knowledge and integrating HBOC risk assessment tools into practice. Identification of individuals at risk is the critical first step in the process of reducing incidence of breast and ovarian cancer associated with BRCA mutations.

The Association between Generalized Anxiety Disorder, Subthreshold Anxiety Symptoms and Fear of Falling among Older Adults: Preliminary Results from a Pilot Study.

OBJECTIVE: A relationship between generalized anxiety disorder (GAD) and fear of falling (FOF) has long been proposed but never specifically studied. This study aimed at analyzing the relationship between FOF and GAD or anxiety symptoms, while controlling for major depressive episodes (MDE), depressive symptoms, fall risk, and sociodemographic variables. METHODS: Twenty-five older adults participated in this pilot study. Assessments included the following: Anxiety Disorder Interview Schedule, Geriatric Anxiety Inventory, Geriatric Depression Scale, Falls-Efficacy Scale-International. A multidisciplinary team evaluated fall risk. RESULTS: FOF was significantly correlated with GAD, MDE, anxiety and depressive symptoms, and fall risk, but not with sociodemographic variables. Multiple regression analyses indicated that GAD and anxiety symptoms were significantly and independently associated with FOF. CONCLUSION: Although the results of this pilot study should be replicated with larger samples, they suggest that FOF is associated with GAD and anxiety symptoms even when considering physical factors that increase the risk of falling. CLINICAL IMPLICATIONS: Treatment of FOF in patients with GAD may present a particular challenge because of the central role of intolerance of uncertainty, which may prevent patients from regaining confidence despite the reduction of fall risk. Clinicians should screen for GAD and anxiety symptoms in patients with FOF to improve detection and treatment.

Implementing a screening tool for identifying patients at risk for hereditary breast and ovarian cancer: a statewide initiative.

BACKGROUND: The Georgia Breast Cancer Genomic Health Consortium is a partnership created with funding from the Centers for Disease Control and Prevention (CDC) to the Georgia Department of Public Health to reduce cancer disparities among high-risk minority women. The project addresses young women at increased risk for hereditary breast and ovarian cancer (HBOC) syndrome through outreach efforts. METHODS: The consortium provides education and collects surveillance data using the breast cancer genetics referral screening tool (B-RST) available at www.BreastCancerGeneScreen.org . The HBOC educational protocol was presented to 73 staff in 6 public health centers. Staff used the tool during the collection of medical history. Further family history assessments and testing for mutations in the BRCA1/2 genes were facilitated if appropriate. RESULTS: Data was collected from November 2012 through December 2013, including 2,159 screened women. The majority of patients identified as black/African American and were 18-49 years old. Also, 6.0 % (n = 130) had positive screens, and 60.9 % (n = 67) of the 110 patients who agreed to be contacted provided a detailed family history. A total of 47 patients (42.7 %) met National Comprehensive Cancer Network guidelines when family history was clarified. Fourteen (12.7 %) underwent genetic testing; 1 patient was positive for a BRCA2 mutation, and 1 patient was found to carry a variant of uncertain significance. CONCLUSIONS: The introduction of genomics practice within public health departments has provided access to comprehensive cancer care for uninsured individuals. The successful implementation of the B-RST into public health centers demonstrates the opportunity for integration of HBOC screening into primary care practices.

Impact of public housing relocations: are changes in neighborhood conditions related to STIs among relocaters?

BACKGROUND: Cross-sectional and ecologic studies suggest that place characteristics influence sexual behaviors and sexually transmitted infections (STIs). Using data from a predominately substance-misusing cohort of African American adults relocating from US public housing complexes, this multilevel longitudinal study tested the hypothesis that participants who experienced greater postrelocation improvements in neighborhood conditions (i.e., socioeconomic disadvantage, social disorder, STI prevalence, and male/female sex ratios) would have reduced the odds of testing positive for an STI over time. METHODS: Baseline data were collected in 2009 from 172 public housing residents before relocations occurred; 3 waves of postrelocation data were collected every 9 months thereafter. Polymerase chain reaction methods were used to test participants' urine for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis. Individual-level characteristics were assessed via survey. Administrative data described the census tracts where participants lived at each wave (e.g., sex ratios, violent crime rates, and poverty rates). Hypotheses were tested using multilevel models. RESULTS: Participants experienced improvements in all tract-level conditions studied and reductions in STIs over time (baseline: 29% tested STI positive; wave 4: 16% tested positive). Analyses identified a borderline statistically significant relationship between moving to tracts with more equitable sex ratios and reduced odds of testing positive for an STI (odds ratio, 0.16; 95% confidence interval, 0.02-1.01). Changes in other neighborhood conditions were not associated with this outcome. DISCUSSION: Consonant with past research, our findings suggest that moving to areas with more equitable sex ratios reduces the risk of STI infection. Future research should study the extent to which this relationship is mediated by changes in sexual network dynamics.

Recurrence Rates and Pharmacological Treatment for Hemorrhoidal Disease: A Systematic Review.

INTRODUCTION: Hemorrhoidal disease (HD) is characterized by prolapse of the inflamed and bleeding vascular tissues of the anal canal. Although HD is associated with a high recurrence rate, there is a lack of understanding around interventions that can reduce recurrence and improve outcomes for patients. As such, a systematic literature review (SLR) was conducted to summarize evidence on epidemiology, recurrence, and efficacy of interventions in HD. METHODS: Real-world evidence (RWE) studies evaluating the incidence, prevalence, or recurrence of HD, as well as SLRs including a meta-analytic component reporting on the efficacy of systemic or topical pharmacological treatments for adults with HD, were included. Systematic searches were conducted in MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Database of Systematic Reviews. RESULTS: The SLR identified 44 eligible publications. Consistent data were limited on the epidemiology of HD or HD recurrence. Specifically, incidence and prevalence reported across geographies were impacted by differences in data collection. Reported risk factors for HD were sedentary behavior, constipation, male gender, and age. Twenty-three RWE studies and one meta-analysis reported HD recurrence rates ranging from 0 to 56.5% following surgery or phlebotonics, with most (n = 19) reporting rates of 20% or less. In addition to time since treatment, risk factors for recurring disease were similar to those for HD in general. With respect to treatment, micronized purified flavonoid fractions significantly improved the main symptoms of HD compared to other pharmacological treatments. CONCLUSION: The SLRs did not identify any RWE studies reporting recurrence in patients receiving systemic or topical treatments, highlighting the need for future research in this area. Further, more studies are needed to understand the optimum duration of medical treatment to prevent recurrence.

Patients with hemorrhoidal disease (HD) can experience recurring disease following a period of improvement or remission. It is not well established how often this might happen, who is at greatest risk, or which treatments can reduce this risk. In this study, a systematic literature review (SLR) was conducted to summarize evidence on the occurrence and recurrence of HD, as well as treatment effectiveness. Several literature databases were searched for articles that described real-world evidence (RWE) studies reporting the epidemiology or recurrence of HD as well as published SLRs that combined the results of multiple studies (meta-analyses) on treatment for adults with HD. Forty of 2037 articles identified by the search were considered relevant, and four others identified by clinicians were also included (total = 44; 39 RWE, 5 meta-analyses). Review of the RWE articles revealed that HD epidemiology was determined differently between studies. Only 23 reported recurrence rates (up to 56.5%) after surgery or treatment with phlebotonic drugs (drugs that improve blood flow in veins). Most (19/23) reported recurrence rates of 20% or less. Risk factors for recurrence were similar to usual HD risk factors (e.g., constipation, male gender, age) in addition to time since treatment. Phlebotonic agents, including those made from plant extracts (micronized purified flavonoid fractions, MPFFs) improved hemorrhoidal symptoms compared with placebo or no treatment. In one meta-analysis, MPFF was the only phlebotonic to significantly reduce recurrence risk versus no treatment or placebo. Overall, more research is needed to compare treatments and determine optimal treatment duration to prevent recurrence. Author-narrated video abstract.

Stated preferences of physicians and chronic pain sufferers in the use of classic strong opioids.

We conducted a two-stage study in France, Germany, Italy, Spain, Sweden, and the United Kingdom of the stated preferences of chronic pain sufferers treated with classic strong opioids and of physicians treating such patients. The qualitative stage identified attributes perceived important through focus groups with 84 pain sufferers and semistructured interviews with 11 physicians. The quantitative stage included online, discrete choice experiments (DCEs) in which respondents chose between hypothetical profiles or an opt-out in 15 choice tasks. The profile descriptions were based on the attributes elicited in the qualitative stage. DCEs were conducted for pain sufferers (N = 242) and physicians (N = 270) who passed a rationality test. Main-effects models were estimated by hierarchical Bayesian regression. Sufferers ranked nausea, pain impact, energy, alertness, and constipation; physicians ranked pain response, central nervous system (CNS) effects, nausea, dose form, and constipation in descending order of importance. Sufferers were unwilling to incur severe side effects to decrease pain and chose the opt-out in approximately one half of the choice tasks, whereas physicians were willing to trade between profiles. The models predicted physicians' choices better than those of pain sufferers. No age, sex, or country effects were seen, but stronger preferences were found among physicians treating noncancer (n = 40) than cancer pain and among the 55% of sufferers who had never discontinued long-term pain medication use. Sufferers' mean pain scores on an 11-point Likert scale were 4.0, 5.7, and 8.6 on their best, average, and worst days, respectively.

Older people presenting to the emergency department after a fall: a population with substantial recurrent healthcare use.

OBJECTIVES: To document patient characteristics, care pathways, healthcare use and costs of fall-related emergency department (ED) presentations by older adults. PARTICIPANTS AND METHODS: All fallers aged ≥70 years, presenting to the ED of a 450-bed metropolitan university hospital in Sydney, Australia (1 April 2007 through 31 March 2009) were studied. Data were collected from the ED electronic information system, ED clinical records and the hospital electronic information system database. Population estimates for 2008 for the local areas served by the hospital were used to estimate ED presentation rates. RESULTS: Of 18 902 all-cause ED presentations, 3220 (17.0%) were due to a fall. Among fallers, 35.4% had one or more ED presentations and 20.3% had had one or more hospital admissions in the preceding 12 months. Fall-related ED presentation led directly to hospital admission in 42.7% of the cases, the majority of which (78.0%) received acute care only (length of stay-14.4 days for men and 13.7 days for women) and the remaining cases underwent further inpatient rehabilitation (length of stay 35.6 days for men and 30.1 days for women). After hospitalisation, 9.5% of patients became first-time residents of long-term care facilities. All fall-related ED presentations and hospitalisations cost a total of A$11 241 387 over the study period. CONCLUSIONS: Older fallers presenting to the ED consume significant healthcare resources and are an easily identifiable high-risk population. They may benefit from systematic fall-risk assessment and tailored fall-prevention interventions.

Prevalence and healthcare resource utilization of patients with Dravet syndrome: Retrospective linkage cohort study.

PURPOSE: Prevalence, demography, antiseizure medication (ASM) usage, healthcare resource utilization (HCRU), and mortality of Dravet syndrome (DS) in the UK were investigated using primary and secondary care data in this retrospective cohort study. METHODS: Patients with confirmed DS were anonymously identified from the UK Clinical Practice Research Datalink (CPRD) GOLD database (01/01/1987-31/10/2018) using the DS Read Codes (F25G.11 or F25G.00). Probable DS was identified using the International Classification of Diseases-10/Read Code for epilepsy plus stiripentol or potassium bromide prescription. CPRD data were linked to the Hospital Episode Statistics database and Office for National Statistics to calculate HCRU and mortality. RESULTS: The prevalence of confirmed (n = 32; 1.1/100,000) and probable (n = 22; 0.6/100,000) DS in 2017 was 1.5/100,000. Most patients with DS (confirmed, n = 22/28; probable, n = 8/14) were aged <18 years in 2017. Mean (standard deviation) ASM usage was 5.5 (2.7) in confirmed DS and 7.6 (3.8) in probable DS, over 3.4 (3.5) years and 10.0 (6.2) years of follow-up, respectively. HCRU (per patient-year) was similarly high in patients with confirmed and probable DS; mainly consisting of general practitioner consultations (mean, 4.8-7.9), outpatient visits (5.6-8.3), hospital admissions (0.9-4), and emergency department visits (0.3-2.3). Fewer than five deaths were recorded in patients with confirmed and probable DS. CONCLUSION: Using linked national healthcare databases, our study showed that the UK prevalence of DS recorded in primary care was low, and most cases were in patients aged <18 years. HCRU and ASM usage were similarly high in confirmed or probable DS.

Pharmacological treatment for chronic venous disease: an umbrella review of systematic reviews.

INTRODUCTION: Chronic venous disease is a persistent venous drainage alteration caused by valvular incompetence and/or outflow obstruction. Disease management includes a variety of treatments, whose evidence and clinical performance in the mid-long term are variable. The objective of this umbrella review was to summarize efficacy data for pharmacological treatments including venoactive drugs from previously published reviews that included a meta-analytic component. EVIDENCE ACQUISITION: Systematic database searches were conducted via Ovid SP on 13 August 2019, covering MEDLINE, Embase, and the Cochrane Database of Systematic Reviews. Reviews that included a meta-analytic component of four or more clinical trials or observational studies reporting on the efficacy of systemic or topical pharmacological treatments for adults with chronic venous disease published since 2010 were eligible for inclusion. EVIDENCE SYNTHESIS: Eleven publications were included in this umbrella review. Change in ankle circumference was the most commonly reported outcome. Overall, several systemic treatments had significant effects compared with placebo on multiple efficacy outcomes, including measures of edema and pain. Out of them, Micronized Purified Flavonoid Fraction had the most comprehensive evidence of effectiveness on main symptoms and signs and on improving quality of life throughout chronic venous disease stages. CONCLUSIONS: Systemic pharmacotherapies represent a valuable therapeutic option in CVD management. As a result of this umbrella review, several gaps were identified with respect to research topics that warrant further investigation, particularly in the category of topical medications.

The design, synthesis and photochemical study of a biomimetic cyclodextrin model of photoactive yellow protein (PYP).

The design, synthesis and study of the photophysical and photochemical properties of the first biomimetic cyclodextrin (CD) model of photoactive yellow protein (PYP) are described. This model bears a deprotonated trans-p-coumaric acid chromophore, covalently linked via a cysteine moiety to a permethylated 6-monoamino ß-CD. NMR and UV/Visible spectroscopy studies showed the formation of strong self-inclusion complexes in water at basic pH. Steady-state photolysis demonstrated that, unlike the free chromophore in solution, excitation of the model molecule leads to the formation of a photoproduct identified as the cis isomer by NMR spectroscopy. These observations provide evidence that the restricted CD cavity offers a promising framework for the design of biomimetic models of the PYP hydrophobic pocket.

New insights into the ultrafast photophysics of oxidized and reduced FAD in solution.

The ultrafast photophysics of oxidized and reduced flavin adenine dinucleotide (FAD) in aqueous solution was studied by broadband UV-vis femtosecond transient absorption spectroscopy. We observed that oxidized FAD (FAD(ox)) in solution readily aggregates at submillimolar concentration. Upon excitation of FAD(ox), three excited-state lifetimes were found and assigned to three different species: the closed (stacked) conformation of the monomer (∼5.4 ps), the open (extended) conformation of the monomer (∼2.8 ns), and the dimer (∼27 ps). In the case of the stacked conformation of the monomer, we show that intramolecular electron transfer from the adenine to the isoalloxazine ring occurs with a time constant of 5.4 ps and is followed by charge recombination on a faster time scale, namely, 390 fs. We additionally demonstrate that deprotonated reduced flavin (FADH(-)) undergoes biphotonic ionization under high excitation fluence and dissociates into a hydrated electron and the neutral semiquinone radical FADH(•).

Prevalence, healthcare resource utilization and mortality of Lennox-Gastaut syndrome: retrospective linkage cohort study.

PURPOSE: To retrospectively investigate the prevalence, demography, antiseizure medication (ASM) usage, healthcare resource utilization (HCRU), and mortality of patients with Lennox-Gastaut syndrome (LGS) in primary and secondary care in the UK. METHODS: Patients with confirmed LGS were anonymously identified from the UK Clinical Practice Research Datalink (CPRD) GOLD database (01/01/1987-31/1b0/2018) using the LGS Read Code (F250500). Probable LGS was identified using the International Classification of Diseases-10/Read Code for epilepsy (Hospital Episode Statistics [HES]/CPRD) plus rufinamide prescription. Period prevalence was calculated based on patients enrolled in CPRD GOLD and alive in 2017. CPRD data were linked to HES to calculate HCRU, and to the Office for National Statistics mortality registry. RESULTS: Period prevalence of LGS was 0.578/10,000 (n = 180), with 74 and 106 patients identified with confirmed (0.289/10,000) and probable LGS (0.420/10,000). Mean (max) ASM usage was ~1 (3) per year. In confirmed LGS, valproate (72%), lamotrigine (69%), and clobazam (66%) were the most commonly prescribed ASMs. HCRU (per patient-year) was similar in confirmed and probable LGS and mostly consisted of primary care general practitioner consultations (4-6), outpatient visits (5-10), inpatient admissions (1-4), and A&E visits (1). During the follow-up period, 18 patients died with crude mortality rates of 6.12 (confirmed LGS) and 4.17 (probable LGS) deaths per 1000 person-years. CONCLUSION: Prevalence of LGS appears low in the UK. The similarly high HCRU and mortality rates in confirmed and probable LGS support the validity and specificity of the probable LGS algorithm and high burden of LGS.

Spectro-temporal characterization of the photoactivation mechanism of two new oxidized cryptochrome/photolyase photoreceptors.

The photoactivation dynamics of two new flavoproteins (OtCPF1 and OtCPF2) of the cryptochrome photolyase family (CPF), belonging to the green alga Ostreococcus tauri , was studied by broadband UV-vis femtosecond absorption spectroscopy. Upon excitation of the protein chromophoric cofactor, flavin adenine dinucleotide in its oxidized form (FAD(ox)), we observed in both cases the ultrafast photoreduction of FAD(ox): in 390 fs for OtCPF1 and 590 fs for OtCPF2. Although such ultrafast electron transfer has already been reported for other flavoproteins and CPF members, the present result is the first demonstration with full spectral characterization of the mechanism. Analysis of the photoproduct spectra allowed identifying tryptophan as the primary electron donor. This residue is found to be oxidized to its protonated radical cation form (WH(*+)), while FAD(ox) is reduced to FAD(*-). Subsequent kinetics were observed in the picosecond and subnanosecond regime, mostly described by a biexponential partial decay of the photoproduct transient signal (9 and 81 ps for OtCPF1, and 13 and 340 ps for OtCPF2), with reduced spectral changes, while a long-lived photoproduct remains in the nanosecond time scale. We interpret these observations within the model proposed by the groups of Brettel and Vos, which describes the photoreduction of FADH(*) within E. coli CPD photolyase (EcCPD) as a sequential electron transfer along a chain of three tryptophan residues, although in that case the rate limiting step was the primary photoreduction in 30 ps. In the present study, excitation of FAD(ox) permitted to reveal the following steps and spectroscopically assign them to the hole-hopping process along the tryptophan chain, accompanied by partial charge recombination at each step. In addition, structural analysis performed by homology modeling allowed us to propose a tentative structure of the relative orientations of FAD and the conserved tryptophan triad. The results of preliminary transient anisotropy measurements performed on OtCPF2 finally showed good compatibility with the oxidation of the distal tryptophan residue (WH(351)) in 340 ps, hence, with the overall Brettel-Vos mechanism.

Characterization of two members of the cryptochrome/photolyase family from Ostreococcus tauri provides insights into the origin and evolution of cryptochromes.

Cryptochromes (Crys) are blue light receptors believed to have evolved from the DNA photolyase protein family, implying that light control and light protection share a common ancient origin. In this paper, we report the identification of five genes of the Cry/photolyase family (CPF) in two green algae of the Ostreococcus genus. Phylogenetic analyses were used to confidently assign three of these sequences to cyclobutane pyrimidine dimer (CPD) photolyases, one of them to a DASH-type Cry, and a third CPF gene has high homology with the recently described diatom CPF1 that displays a bifunctional activity. Both purified OtCPF1 and OtCPF2 proteins show non-covalent binding to flavin adenine dinucleotide (FAD), and additionally to 5,10-methenyl-tetrahydrofolate (MTHF) for OtCPF2. Expression analyses revealed that all five CPF members of Ostreococcus tauri are regulated by light. Furthermore, we show that OtCPF1 and OtCPF2 display photolyase activity and that OtCPF1 is able to interact with the CLOCK:BMAL heterodimer, transcription factors regulating circadian clock function in other organisms. Finally, we provide evidence for the involvement of OtCPF1 in the maintenance of the Ostreococcus circadian clock. This work improves our understanding of the evolutionary transition between photolyases and Crys.

Photoinduced cation translocation in a calix[4]biscrown: towards a new type of light-driven molecular shuttle.

The photophysics of a ditopic receptor of potassium ion consisting of a 1,3-alternate calix[4]biscrown with a merocyanine dye (DCM) inserted into each crown is reported. Thanks to the large difference between the binding affinity for one and two potassium ions, one can find relative total concentrations of ligand and potassium ion at which the 1:1 complex is most predominant with respect to the free ligand and the 2:1 complex whose amounts are a few percents. Investigation of the 1:1 complex by femtosecond transient absorption spectroscopy provides evidence for the ultrafast movement of a potassium ion through the calix[4]arene tube upon excitation at 400 nm of the dye. Phototranslocation occurs in the picosecond timescale with a non-exponential kinetics without competition with photoejection towards the bulk. The translocation time includes two main short components: 0.83 ps and 10 ps. A smaller-weighted third component of 101 ps might include a competition between phototranslocation and excitation energy transfer as shown by using Förster's theory. These findings open the way to new strategies for light-driven molecular shuttles with the aim of information storage and binary logic computing at a nanometric scale.