Monolithic Two-Terminal Tandem Solar Cells Using Sb2S3 and Solution-Processed PbS Quantum Dots Achieving an Open-Circuit Potential beyond 1.1 V

Multijunction solar cells have the prospect of a greater theoretical efficiency limit than single-junction solar cells by minimizing the transmissive and thermalization losses a single absorber material has. In solar cell applications, Sb2S3 is considered an attractive absorber due to its elemental abundance, stability, and high absorption coefficient in the visible range of the solar spectrum, yet with a band gap of 1.7 eV, it is transmissive for near-IR and IR photons. Using it as the top cell (the cell where light is first incident) in a two-terminal tandem architecture in combination with a bottom cell (the cell where light arrives second) of PbS quantum dots (QDs), which have an adjustable band gap suitable for absorbing longer wavelengths, is a promising approach to harvest the solar spectrum more effectively. In this work, these two subcells are monolithically fabricated and connected in series by a poly(3,4-ethylene-dioxythiophene) polystyrene sulfonate (PEDOT:PSS)-ZnO tunnel junction as the recombination layer. We explore the surface morphology of ZnO QD films with different spin-coating conditions, which serve as the PbS QD cell's electron transport material. Furthermore, we examine the differences in photogenerated current upon varying the PbS QD absorber layer thickness and the electrical and optical characteristics of the tandem with respect to the stand-alone reference cells. This tandem architecture demonstrates an extended spectral response into the IR with an open-circuit potential exceeding 1.1 V and a power conversion efficiency of 5.6%, which is greater than that of each single-junction cell.

Estimates of Current Capacity for Diagnosing Alzheimer's Disease in Sweden and the Need to Expand Specialist Numbers

BACKGROUND

The emergence of disease-modifying Alzheimer's (AD) treatments provides new hope to patients and families but concerns have been raised about the preparedness of healthcare systems to provide timely access to such treatments because of a combination of a complex diagnostic process and a large prevalent pool.

OBJECTIVES

We assess the preparedness of Sweden, a high-income country known for its dementia-friendly policies, to diagnose AD patients eligible for treatment within a six-month window, given current capacity for specialist evaluations and biomarker testing. We calculate the investment requirements for Sweden to achieve this target over a timeframe of 20 years.

DESIGN

Desk research to identify data for population, mortality, disease burden, cost of services and current capacity, expert consultation to inform assumptions about patient journey, and use of a Markov model to predict waiting times. The model simulates the patients' journey through different evaluation stages: initial evaluation by a primary care specialist, neurocognitive testing by an AD specialist, and confirmatory biomarker testing with PET scanning or cerebrospinal fluid (CSF) testing. The model assumes specialist appointments and PET scans are capacity constrained, and patients progress from cognitively normal to MCI and from MCI to dementia in the resulting waiting times.

MEASUREMENTS

Projected waiting times for diagnosis of eligibility for disease-modifying Alzheimer's treatment from 2023 to 2042 assuming current capacity, assuming 20% of Swedish residents aged 60 years and above would seek an evaluation for cognitive decline. Investments required to scale capacity up to reach target of providing diagnosis within six months on average.

RESULTS

Initial average waiting times for AD specialist appointments would be around 21 months in 2023 and remain around 55 months through 2042, as demand would continue to outstrip supply throughout the 20-year model horizon. Waiting times for biomarker testing would be stable at less than four weeks, as patients would be held up in the queue for their first specialist consultations, and use of CSF testing is widely accepted in Sweden. An additional 25% of AD specialists would have to be added above the current growth trend to reduce waiting times to less than 6 months at an average annual cost of approximately 805 million SEK. The increased cost of volume of biomarker testing would amount to about 106 million SEK per year.

CONCLUSIONS

At current capacity, the Swedish healthcare system is unable to provide timely diagnosis of patients eligible for disease-modifying AD treatment. Although future diagnostic technologies, such as digital cognitive assessments and blood tests for the AD pathology, might decrease demand for capacity-constrained services, substantial investments will be required to meet a target of less than six months of waiting time for a diagnosis.

Fingerprinting of chlorinated paraffins and their transformation products in plastic consumer products

Chlorinated paraffins (CPs) can be classified according to their length as short-chain (SC, C10-C13), medium-chain (MC, C14-C17) and long-chain (LC, C ≥ 18) CPs. Technical CP-mixtures can contain a wide range of carbon- (C-, nC = 10-30) and chlorine- (Cl-, nCl = 3-19) homologues. CPs are high-production volume chemicals (>106 t/y). They are used as flame-retardants, plasticizers and coolant fluids. Due to the persistence, bioaccumulation, long-range environmental transport potential and adverse effects, SCCPs are regulated as persistent organic pollutants (POPs) by the Stockholm Convention. Transformation of CPs can lead to the formation of unsaturated compounds such as chlorinated mono- (CO), di- (CdiO) and tri-olefins (CtriO). Such transformation reactions can occur at different stages of CP manipulation providing characteristic C-/Cl-homologue distributions. All this results in unique patterns that collectively create a fingerprint, which can be distinguished from CP-containing samples. Therefore, CP-fingerprinting can develop into a promising tool for future source apportionment studies and with it, the reduction of environmental burden of CPs and hazards to humans. Herein, CP-containing plastics were studied to establish fingerprints and develop this method. We analyzed four household items by reverse-phase liquid-chromatography coupled with a mass spectrometer with an atmospheric pressure chemical ionization source and an Orbitrap mass analyzer (RP-LC-APCI-Orbitrap-MS) operated at a resolution of 120000 (FWHM at m/z 200). MS-data of different CP-, CO-, CdiO- and CtriO-homologues were efficiently processed with an R-based automatic mass spectra evaluation routine (RASER). From the 16720 ions searched for, up to 4300 ions per sample were assigned to 340 C-/Cl-homologues of CPs and their transformation products. Specific fingerprints were deduced from the C-/Cl-homologues distributions, the carbon- (nC) and chlorine- (nCl) numbers and saturation degree. These fingerprints were compared with the ones obtained by a GC-ECNI-Orbitrap-MS method.

Plasma and cerebrospinal fluid concentrations of neurofilament light protein correlate in patients with idiopathic normal pressure hydrocephalus

BACKGROUND

Neurofilament light chain protein (NFL), a marker of neuronal axonal degeneration, is increased in cerebrospinal fluid (CSF) of patients with idiopathic normal pressure hydrocephalus (iNPH). Assays for analysis of NFL in plasma are now widely available but plasma NFL has not been reported in iNPH patients. Our aim was to examine plasma NFL in iNPH patients and to evaluate the correlation between plasma and CSF levels, and whether NFL levels are associated with clinical symptoms and outcome after shunt surgery.

METHODS

Fifty iNPH patients with median age 73 who had their symptoms assessed with the iNPH scale and plasma and CSF NFL sampled pre- and median 9 months post-operatively. CSF plasma was compared with 50 healthy controls (HC) matched for age and gender. Concentrations of NFL were determined in plasma using an in-house Simoa method and in CSF using a commercially available ELISA method.

RESULTS

Plasma NFL was elevated in patients with iNPH compared to HC (iNPH: 45 (30-64) pg/mL; HC: 33 (26-50) (median; Q1-Q3), p = 0.029). Plasma and CSF NFL concentrations correlated in iNPH patients both pre- and postoperatively (r = 0.67 and 0.72, p < 0.001). We found only weak correlations between plasma or CSF NFL and clinical symptoms and no associations with outcome. A postoperative NFL increase was seen in CSF but not in plasma.

CONCLUSIONS

Plasma NFL is increased in iNPH patients and concentrations correlate with CSF NFL implying that plasma NFL can be used to assess evidence of axonal degeneration in iNPH. This finding opens a window for plasma samples to be used in future studies of other biomarkers in iNPH. NFL is probably not a very useful marker of symptomatology or for prediction of outcome in iNPH.

Brain charts for the human lifespan

Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes.

Extensor tendon ruptures in rheumatoid wrists

Background and aims

Rheumatoid arthritis is a chronic inflammatory disease. The associated involvement of hands and tendons is over 90% and impairs overall function. In the course of the disease, the joints are often operated on. During this operation, ruptures of the extensor tendons are found by chance without the patients noticing them. The aim of this retrospective study is the prevalence of extensor tendon rupture. Which tendon is destroyed most frequently? How can the functional outcome be measured after reconstruction?

Materials and methods

From 1572 operations on rheumatoid wrists, 61 extensor tendon ruptures were identified in 41 patients. The average time between the first rheumatic symptoms of the hand and surgery was 6.4 years. The average duration of RA was 7.8 years. 26 patients with 27 tendon reconstructions were included in the follow-up with an average postoperative duration of 4.6 years (3 to 14.2 years).

Results

Extensor tendons ruptures typically occurred at mechanically stressed sites. The most frequent rupture was found in the extensor pollicis longus tendon (21 tendons), followed by the small finger extensor tendon (14 tendons). A transfer was performed on 7 tendons. Fifty-five tendon lesions were sutured at other intact tendons. Free grafts were not used. The results in Clayton and QuickDASH scores were significantly different. Functional improvement was consistent with the results of tendon reconstructions in healthy control groups.

Conclusion

In rheumatoid patients, a rupture of an extensor tendon must be expected at 4%. Patients tolerate and compensate this damage for a long time. The function of the hand including the tendon function is the most important factor in assessing the success of the operation. The subjective patient acceptance depends on the progress of the underlying disease, postoperative care (ergotherapy, physiotherapy, orthosis) and the patients' demands.

Electronic supplementary material

The online version of this article (10.1007/s00590-020-02731-1) contains supplementary material, which is available to authorized users.

Atrial fibrillation increases the risk of dementia amongst older adults even in the absence of stroke

BACKGROUND

Atrial fibrillation increases risk of stroke, and thus risk of cognitive impairment and dementia. Emerging evidence suggests an association also in the absence of stroke. We aimed to examine the association between atrial fibrillation and incident dementia, with and without exclusion of individuals with stroke, and if sex and genetic factors modify the possible association.

METHODS

In 2000-2001, a population-based sample of 70-year-olds (N = 561) underwent comprehensive somatic and neuropsychiatric examinations, as part of the Gothenburg H70 Birth Cohort Studies. Participants were followed up at age 75 and 79. Atrial fibrillation at baseline was identified through ECG, proxy-reports and the National Patient Register (NPR). Stroke at baseline and follow-up was identified through self-reports, proxy-reports and the NPR. Dementia at baseline and follow-up was diagnosed according to the DSM-III-R criteria based on neuropsychiatric examinations, proxy-reports and the NPR.

RESULTS

Individuals with atrial fibrillation had an almost threefold increased risk of dementia during 12-year follow-up (HR 2.8; 95% CI 1.3-5.7; P = 0.004), and this risk remained after excluding individuals with stroke at baseline and follow-up. After stratification for sex, the association was only found amongst men (HR 4.6; 95% CI 1.9-11.2; P < 0.001, interaction sex*atrial fibrillation; P = 0.047) and noncarriers of the APOE ε4 allele (HR 4.2; 95% CI 1.8-9.7; P < 0.001, interaction APOE*atrial fibrillation; P = 0.128). Population attributable risk for dementia resulting from atrial fibrillation was 13%.

CONCLUSION

The relevance for atrial fibrillation as an indicator of subclinical brain vascular risk needs to be further explored. In addition, patients with atrial fibrillation should be screened for cognitive symptoms.

Epidemiology of suicidal feelings in an ageing Swedish population: from old to very old age in the Gothenburg H70 Birth Cohort Studies

AIMS

The first aim of this study was to provide prevalence suicidal feelings over time (past week, past month, past year and lifetime) in a population-based sample of old to very old adults without dementia. Does prevalence change with rising age? The second aim was to examine the fluctuation of suicidal feelings over time. How does this coincide with depression status?

METHODS

Data were derived from the Gothenburg H70 Birth Cohort Studies (the H70 studies) which are multidisciplinary longitudinal studies on ageing. A representative sample of adults in Gothenburg, Sweden with birth years 1901-1944 were invited to take part in a longitudinal health study on ageing and participated at one or more occasions during 1986-2014. The sample consisted of 6668 observations originating from 3972 participants without dementia between the ages of 70 and 108, including 1604 participants with multiple examination times. Suicidal feelings were examined during a psychiatric interview using the Paykel questions (life not worth living, death wishes, thoughts of taking own life, seriously considered taking life, attempted suicide).

RESULTS

Prevalence figures for suicidal feelings of any severity were as follows: past week 4.8%, past month 6.7%, past year 11.2% and lifetime 25.2%. Prevalence rates increased with age in the total group and in women but not in men. Suicidal feelings were common in participants with concurrent major or minor depression, but over a third of the participants who reported suicidal feelings did not fulfil criteria for these diagnoses nor did they present elevated mean depressive symptom scores. The majority of participants consistently reported no experience of suicidal feelings over multiple examination times, but fluctuation was more common in women compared with men.

CONCLUSION

Suicidal feelings in late-life are uncommon in individuals without depression indicating that such behaviour is not a widespread, normative phenomenon. However, such feelings may occur outside the context of depression.

Depression and neuroticism decrease among women but not among men between 1976 and 2016 in Swedish septuagenarians

OBJECTIVES

We evaluated birth-cohort differences in depressive symptom burden, prevalence of depression diagnoses, and neuroticism, among Swedish 70-year-olds examined between 1976 and 2016.

METHODS

We used a repeated cross-sectional design examining four representative population samples of Swedish 70-year-olds (total n = 2279) with identical methods in 1976-77 (n = 392), 1992-93 (n = 226), 2000-02 (n = 487), and 2014-16 (n = 1166). Depressive symptom burden was rated with the Montgomery Åsberg Depression Rating Scale. Major depression was diagnosed according to DSM-5, and minor depression according to DSM-IV-TR research criteria. Neuroticism was rated with the Eysenck Personality Inventory.

RESULTS

For women in 2014-16, MADRS score (4.4 vs. 6.1 vs. 5.8; P < 0.05) and neuroticism (6.6 vs. 7.7 vs. 9.2; P < 0.05) were lower compared with 1992-93 and 1976-77, and the prevalence of any depression was lower compared with 2000-02 and 1992-93 (10.9% vs. 16.9% vs. 18.1%; P < 0.05). For men, we observed no birth-cohort differences in depression, while neuroticism was found to be lower in 2014-16 compared with 1976-77 among men without depression (5.1 vs. 5.9; P < 0.01). The sex difference for MADRS and neuroticism declined between 1976-77 and 2014-16 (cohort*sex P < 0.05).

CONCLUSIONS

Depressive burden and neuroticism decreased in 70-year-old women between 1976 and 2016.

Publisher Correction: Preclinical amyloid pathology biomarker positivity: effects on tau pathology and neurodegeneration

The Article was originally published under a CC BY-NC-ND 4.0 license, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the Article have been modified accordingly.

Attenuation of atherogenic apo B-48-dependent hyperlipidemia and high density lipoprotein remodeling induced by vitamin C and E combination and their beneficial effect on lethal ischemic heart disease in mice

Background and aims

Atherosclerotic cardiovascular disease is highly prevalent and its underlying pathogenesis involves dyslipidemia including pro-atherogenic high density lipoprotein (HDL) remodeling. Vitamins C and E have been proposed as atheroprotective agents for cardiovascular disease management. However, their effects and benefits on high density lipoprotein function and remodeling are unknown. In this study, we evaluated the role of vitamin C and E on non HDL lipoproteins as well as HDL function and remodeling, along with their effects on inflammation/oxidation biomarkers and atherosclerosis in atherogenic diet-fed SR-B1 KO/ApoER61^h/h mice.

Methods and results

Mice were pre-treated for 5 weeks before and during atherogenic diet feeding with vitamin C and E added to water and diet, respectively. Compared to a control group, combined vitamin C and E administration reduced serum total cholesterol and triglyceride levels by decreasing apo B-48-containing lipoproteins, remodeled HDL particles by reducing phospholipid as well as increasing PON1 and apo D content, and diminished PLTP activity and levels. Vitamin supplementation improved HDL antioxidant function and lowered serum TNF-α levels. Vitamin C and E combination attenuated atherogenesis and increased lifespan in atherogenic diet-fed SR-B1 KO/ApoER61^h/h mice.

Conclusions

Vitamin C and E administration showed significant lipid metabolism regulating effects, including HDL remodeling and decreased levels of apoB-containing lipoproteins, in mice. In addition, this vitamin supplementation generated a cardioprotective effect in a murine model of severe and lethal atherosclerotic ischemic heart disease.

CSF YKL-40 and GAP-43 are related to suicidal ideation in older women

OBJECTIVE

To investigate possible relationships between suicidal ideation and cerebrospinal fluid (CSF) levels of glial markers YKL-40 (also known as chitinase-3-like protein 1), growth-associated protein-43 (GAP-43) and myelin basic protein (MBP).

METHOD

The sample was obtained from the Prospective Population Study of Women and included 86 women without dementia who underwent both psychiatric examinations and lumbar puncture (LP). Eight of these women reported past-month suicidal ideation.

RESULTS

Significantly, higher CSF levels of both YKL-40 and GAP-43 were detected in women with past-month suicidal ideation. Associations with suicidal ideation remained for both YKL-40 and GAP-43 in regression models adjusted for smoking status, BMI and age. CSF levels of YKL-40, GAP-43 and MBP did not differ by depression status. Higher levels of CSF GAP-43 were associated with feelings of worthlessness; a strong relationship was demonstrated in the fully adjusted model (OR 5.95 CI [1.52-23.20], P = 0.01).

CONCLUSION

Our findings of elevated CSF concentrations of both YKL-40 and GAP-43 in women with suicidal ideation, compared to those without, suggest that a disrupted synaptic glial functioning and inflammation may be related to the aetiology of suicidal ideation in older adults.

Preclinical amyloid pathology biomarker positivity: effects on tau pathology and neurodegeneration

Brain autopsy and biomarker studies indicate that the pathology of Alzheimer's disease (AD) is initiated at least 10-20 years before clinical symptoms. This provides a window of opportunity to initiate preventive treatment. However, this emphasizes the necessity for biomarkers that identify individuals at risk for developing AD later in life. In this cross-sectional study, originating from three epidemiologic studies in Sweden (n=1428), the objective was to examine whether amyloid pathology, as determined by low cerebrospinal fluid (CSF) concentration of the 42 amino acid form of β-amyloid (Aβ42), is associated with biomarker evidence of other pathological changes in cognitively healthy elderly. A total of 129 patients were included and CSF levels of Aβ42, total tau, tau phosphorylated at threonine 181 (p-tau), neurogranin, VILIP-1, VEGF, FABP3, Aβ40, neurofilament light, MBP, orexin A, BDNF and YKL-40 were measured. Among these healthy elderly, 35.6% (N=46) had CSF Aβ42 levels below 530 pg ml^-1. These individuals displayed significantly higher CSF concentrations of t-tau (P<0.001), p-tau (181) (P<0.001), neurogranin (P=0.009) and FABP3 (P=0.044) compared with amyloid-negative individuals. Our study indicates that there is a subpopulation among healthy older individuals who have amyloid pathology along with signs of ongoing neuronal and synaptic degeneration, as well as tangle pathology. Previous studies have demonstrated that increase in CSF tau and p-tau is a specific sign of AD progression that occurs downstream of the deposition of Aβ. On the basis of this, our data suggest that these subjects are at risk for developing AD. We also confirm the association between APOE ɛ4 and amyloid pathology in healthy older individuals.

The knee joint in early juvenile idiopathic arthritis: An ROC study for evaluating the diagnostic accuracy of contrast-enhanced MR imaging

Purpose: Diagnosis of juvenile idiopathic arthritis (JIA) remains difficult due to unspecific clinical and laboratory findings, especially in early stages of the disease. The purpose of our study was to determine the sensitivity and specificity of MR imaging in diagnosing JIA of the knee joints.

Material and Methods: Forty children (3–17 years old) clinically diagnosed with JIA (follow-up >1 year) of a knee joint and a control group of 40 children with painful knee joints (MR diagnosis: bone bruise of the knee (n=7), normal knee joint (n=12), osteomyelitis (n=6), septic arthritis (n=2), bone tumor (n=7) and miscellaneous bone lesions (n=6)) were examined using a 1.5 T MR unit. T1-weighted spin-echo (SE), T2-weighted fast SE, contrast-enhanced T1-weighted SE and 2D gradient echo sequences were performed. The receiver operating characteristic (ROC) curves evaluation was conducted by 5 independent radiologists.

Results: The positive criteria for diagnosing JIA were joint effusions (n=40), contrast-enhancing synovitis (n=39), cartilage lesions (n=15), subchondral erosions and bony destruction (n=1). Sensitivity and specificity were 93.5= and 92.5=, respectively. Both cases of septic arthritis were misdiagnosed as JIA by all radiologists.

Conclusion: Contrast-enhanced MR imaging seems to be a highly sensitive tool in establishing the diagnosis of JIA.

White matter lesions and temporal lobe atrophy related to incidence of both dementia and major depression in 70-year-olds followed over 10 years

BACKGROUND AND PURPOSE

A number of studies have suggested associations between dementia and depression in older adults. One reason could be that these disorders share structural correlates, such as white matter lesions (WMLs) and cortical atrophy. No study has examined whether these lesions precede both dementia and depression independently of each other in the general population.

METHODS

Whether WMLs and cortical atrophy on computed tomography predict dementia and depression was investigated in a population-based sample of 70-year-olds (n = 380) followed over 10 years. Exclusion criteria were dementia, major depression, history of stroke and a Mini-Mental State Examination score below 26 at baseline in 2000-2001. Dementia was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, third edition, revised, and depression according to the Diagnostic and Statistical Manual of Mental Disorders, fifth edition. Primary outcomes included dementia and major depression at 10-year follow-up.

RESULTS

Adjusted logistic regression models, including both WMLs and temporal lobe atrophy, showed that moderate to severe WMLs [odds ratio (OR) 3.96, 95% confidence interval (CI) 1.23-12.76] and temporal lobe atrophy (OR 2.93, 95% CI 1.13-7.60) predicted dementia during a 10-year follow-up independently of major depression. Similarly, both moderate to severe WMLs (OR 3.84, 95% CI 1.25-11.76) and temporal lobe atrophy (OR 2.52, 95% CI 1.06-5.96) predicted depression even after controlling for incident dementia.

CONCLUSION

White matter lesions and temporal lobe atrophy preceded 10-year incidence of both dementia and depression in 70-year-olds. Shared structural correlates could explain the reported associations between dementia and depression. These brain changes may represent independent and complementary pathways to dementia and depression. Strategies to slow progression of vascular pathology and neurodegeneration could indirectly prevent both dementia and depression in older adults.

Inhibition of the SR protein-phosphorylating CLK kinases of Plasmodium falciparum impairs blood stage replication and malaria transmission

Cyclin-dependent kinase-like kinases (CLKs) are dual specificity protein kinases that phosphorylate Serine/Arginine-rich (SR) proteins involved in pre-mRNA processing. Four CLKs, termed PfCLK-1-4, can be identified in the human malaria parasite Plasmodium falciparum, which show homology with the yeast SR protein kinase Sky1p. The four PfCLKs are present in the nucleus and cytoplasm of the asexual blood stages and of gametocytes, sexual precursor cells crucial for malaria parasite transmission from humans to mosquitoes. We identified three plasmodial SR proteins, PfSRSF12, PfSFRS4 and PfSF-1, which are predominantly present in the nucleus of blood stage trophozoites, PfSRSF12 and PfSF-1 are further detectable in the nucleus of gametocytes. We found that recombinantly expressed SR proteins comprising the Arginine/Serine (RS)-rich domains were phosphorylated by the four PfCLKs in in vitro kinase assays, while a recombinant PfSF-1 peptide lacking the RS-rich domain was not phosphorylated. Since it was hitherto not possible to knock-out the pfclk genes by conventional gene disruption, we aimed at chemical knock-outs for phenotype analysis. We identified five human CLK inhibitors, belonging to the oxo-β-carbolines and aminopyrimidines, as well as the antiseptic chlorhexidine as PfCLK-targeting compounds. The six inhibitors block P. falciparum blood stage replication in the low micromolar to nanomolar range by preventing the trophozoite-to-schizont transformation. In addition, the inhibitors impair gametocyte maturation and gametogenesis in in vitro assays. The combined data show that the four PfCLKs are involved in phosphorylation of SR proteins with essential functions for the blood and sexual stages of the malaria parasite, thus pointing to the kinases as promising targets for antimalarial and transmission blocking drugs.

Changes in the transcriptome of the malaria parasite Plasmodium falciparum during the initial phase of transmission from the human to the mosquito

BACKGROUND

The transmission of the malaria parasite Plasmodium falciparum from the human to the mosquito is mediated by dormant sexual precursor cells, the gametocytes, which become activated in the mosquito midgut. Because gametocytes are the only parasite stages able to establish an infection in the mosquito, they play a crucial role in spreading the tropical disease. The human-to-mosquito transmission triggers important molecular changes in the gametocytes, which initiate gametogenesis and prepare the parasite for life-cycle progression in the insect vector.

RESULTS

To better understand gene regulations during the initial phase of malaria parasite transmission, we focused on the transcriptome changes that occur within the first half hour of parasite development in the mosquito. Comparison of mRNA levels of P. falciparum gametocytes before and 30 min following activation using suppression subtractive hybridization (SSH) identified 126 genes, which changed in expression during gametogenesis. Among these, 17.5% had putative functions in signaling, 14.3% were assigned to cell cycle and gene expression, 8.7% were linked to the cytoskeleton or inner membrane complex, 7.9% were involved in proteostasis and 6.4% in metabolism, 12.7% were cell surface-associated proteins, 11.9% were assigned to other functions, and 20.6% represented genes of unknown function. For 40% of the identified genes there has as yet not been any protein evidence.For a subset of 27 genes, transcript changes during gametogenesis were studied in detail by real-time RT-PCR. Of these, 22 genes were expressed in gametocytes, and for 15 genes transcript expression in gametocytes was increased compared to asexual blood stage parasites. Transcript levels of seven genes were particularly high in activated gametocytes, pointing at functions downstream of gametocyte transmission to the mosquito. For selected genes, a regulated expression during gametogenesis was confirmed on the protein level, using quantitative confocal microscopy.

CONCLUSIONS

The obtained transcriptome data demonstrate the regulations of gene expression immediately following malaria parasite transmission to the mosquito. Our findings support the identification of proteins important for sexual reproduction and further development of the mosquito midgut stages and provide insights into the genetic basis of the rapid adaption of Plasmodium to the insect vector.

[Chronically ill and unemployed? A review on vocational status in multiple sclerosis]

BACKGROUND

Multiple sclerosis (MS) is one of the most common neurological disorders in young adults. It is characterised by a chronic progressive course with far reaching implications on the patient's private and professional life. Based on the current literature, employment status is analysed in relation to disease-specific, therapeutic, psychosocial, and socioeconomic factors. A special emphasis is placed on the vocational status of MS patients in Germany.

RESULTS

According national and international studies, around 40 % of all MS patients are currently unemployed. Main reasons for early retirement are disease-specific factors such as impaired mobility, disability in the upper extremities, fatigue, and cognitive impairment. According to the German Multiple Sclerosis Registry (GMSR), these symptoms are still insufficiently treated. In patients with minor motoric impairment (EDSS ≤ 3.0), depressive symptoms seem to have a major impact on employment status. Disease progression, older age at diagnosis, and hard physical work are negative predictors in terms of employment situation. The lack of flexible working hours, the inability to have flexible resting times at work, a lack of understanding from colleagues and employers as well as the personal attitude were main non-disease-specific reasons for early retirement.

CONCLUSIONS

The current knowledge on the vocational status in MS is mainly based on international studies (e. g., Scandinavia, England, USA, Australia, MSIF Survey). For Germany, only the GMSR supports significant information on the employment status of MS patients. According to the GMSR, ataxia, fatigue and cognitive dysfunction are still insufficiently treated - a situation that is at least partly due to insufficient treatment options. Comprehensive studies that focus on a broad range of possible influencing factors on vocational status of German MS patients are currently lacking.

Circadian cortisol, depressive symptoms and neurological impairment in early multiple sclerosis

OBJECTIVE

There is evidence for the existence of a hyperactive hypothalamus-pituitary-adrenal (HPA) axis and its potential role in disease progression in multiple sclerosis (MS). Depressive symptoms are also common in MS. At the same time, depressive symptoms are often associated with an elevated circadian cortisol secretion. So far, little is known about the interplay between depressive symptoms and circadian HPA axis abnormalities in MS.

METHODS

Here we investigated depressive symptoms, circadian HPA axis function, cortisol awakening response (CAR) and neurological impairment in 32 early stage relapsing-remitting MS (RRMS) patients and 16 age- and sex-matched controls. Saliva cortisol samples were collected in patients' home environment. Depressive symptoms were assessed by self-report measures. Neurological impairment was assessed by the Kurtzke Expanded Disability Status Scale (EDSS).

RESULTS

RRMS patients expressed a significantly higher CAR when compared to healthy controls. After patients were divided into two groups based on their depressive symptom load (Beck Depression Inventory (BDI); median-split), only RRMS patients with moderately elevated depression scores (BDI high) statistically differed in their cortisol release when compared to healthy controls. RRMS patients with low depression scores (BDI low) expressed similar circadian patterns as healthy controls. Neurological impairment (EDSS) was more pronounced in the BDI high group than in the BDI low group.

CONCLUSION

In summary, there is evidence, that a hyperactive HPA axis is primarily present in MS patients expressing moderately elevated depressive symptoms. MS patients with only few depressive symptoms do not significantly differ in CAR when compared to healthy controls. To the best of our knowledge, this is the first study showing that in early stage MS, a hyperactive HPA axis is primarily present in patients who express moderate depressive symptoms.

Two nucleus-localized CDK-like kinases with crucial roles for malaria parasite erythrocytic replication are involved in phosphorylation of splicing factor

The kinome of the human malaria parasite Plasmodium falciparum comprises representatives of most eukaryotic protein kinase groups, including kinases which regulate proliferation and differentiation processes. Despite extensive research on most plasmodial enzymes, little information is available regarding the four identified members of the cyclin-dependent kinase-like kinase (CLK) family. In other eukaryotes, CLKs regulate mRNA splicing through phosphorylation of Serine/Arginine-rich proteins. Here, we investigate two of the PfCLKs, the Lammer kinase homolog PfCLK-1, and PfCLK-2. Both PfCLKs show homology with the yeast Serine/Arginine protein kinase Sky1p and are transcribed throughout the asexual blood stages and in gametocytes. PfCLK-1/Lammer possesses two nuclear localization signal sites and PfCLK-2 possesses one of these signal sites upstream of the C-terminal catalytic domains. Indirect immunofluorescence, Western blot, and electron microscopy data confirm that the kinases are primarily localized in the parasite nucleus, and PfCLK-2 is further present in the cytoplasm. The two kinases are important for completion of the asexual replication cycle of P. falciparum, as demonstrated by reverse genetics approaches. In vitro kinase assays show substrate phosphorylation by the PfCLKs, including the Sky1p substrate, splicing factor Npl3p, and the plasmodial alternative splicing factor PfASF-1. Mass spectrometric analysis of co-immunoprecipitated proteins indicates assembly of the two PfCLKs with proteins with predicted nuclease, phosphatase, or helicase functions. Our data indicate a crucial role of PfCLKs for malaria blood stage parasites, presumably by participating in gene regulation through the post-transcriptional modification of mRNA.

Neurological disability, psychological distress, and health-related quality of life in MS patients within the first three years after diagnosis

BACKGROUND

Psychological distress and psychiatric co-morbidity are common in multiple sclerosis (MS) and is often associated with neurological disability as well as reduced quality of life.

OBJECTIVES

This study aimed to investigate psychological distress and the possible association with quality of life as well as neurological disability in MS patients within the first 3 years after diagnosis.

METHODS

Psychological distress was measured using a standardized questionnaire (Symptom-Check-List-90-R; SCL-90-R) in 31 relapsing-remitting MS patients and 24 sex- and age-matched healthy controls.

RESULTS

Psychological distress was significantly more pronounced in MS patients when compared to healthy controls. Interpersonal sensitivity and psychoticism were positively associated with neurological disability (Expanded Disability Status Scale [EDSS]). A high EDSS group (median split EDSS; 1.5) expressed significantly more psychological distress when compared to the low EDSS group and healthy controls. MS patients with minimal to no neurological disability (low EDSS group) also expressed significantly more emotional distress when compared to healthy controls. MS-related quality of life was positively associated with neurological disability as well as SCL-90-R scores. After adjusting for neurological disability, psychological distress was still significantly associated with quality of life.

CONCLUSIONS

Early stage MS patients significantly differ in their psychological distress when compared to healthy controls. Psychological distress in these patients is associated with neurological disability, but it is also present in patients with minimal to no neurological disability. Psychological distress was identified as an independent predictor for MS-related quality of life.

Subcutaneous scalp emphysema, pneumo-orbitis and pneumocephalus in a neonate on high humidity high flow nasal cannula

High humidity high flow nasal cannula has become a widely used alternative for nasal continuous positive airway pressure for the treatment of apnea of prematurity. We describe our experience of one incident of subcutaneous scalp emphysema, pneumo-orbitis and pneumocephalus with concomitant use of the high-flow nasal cannula.

[Adherence to neurologic treatment. Lessons from multiple sclerosis]

In light of increasing prevalence rates of chronic conditions and a growing elderly population, patients' nonadherence to medical regimes reflects a significant problem in modern health care. In the past, patients were primarily held responsible for problematic adherence. Over the past decades this attitude has changed dramatically, and it is now acknowledged that lack of adherence reflects a problem requiring different approaches and interventions on many different levels. Here we highlight central aspects and consequences of adherence problems in long-term therapy. Factors affecting treatment motivation in multiple sclerosis patients are summarized focusing on neurologic treatment issues, and specific intervention strategies for patients, doctors, and nurses are discussed.

Personality characteristics in chronic and non-chronic allergic conditions

In psycho-allergological research, the potential relevance of personality factors in the maintenance and exacerbation of atopic symptoms is still a matter of debate. The present study aimed to assess personality dimensions in chronic atopic disease, i.e. atopic dermatitis (AD) and in acute manifestation of atopy (seasonal allergic rhinitis, SAR). Further, the association of a potentially atopy-specific personality profile with atopy-relevant biological stress responses should be evaluated. Subjects suffering from AD (n=36), or SAR (n=20) and non-atopic controls (n=37) were investigated. To determine different personality domains, Spielberger's State-Trait Anxiety Inventory (STAI), the Questionnaire for Competence and Control (FKK) and the Questionnaire for Stress Vulnerability (MESA) were administered. To assess the relation between these personality dimensions and biological stress responses, atopics and non-atopic controls were exposed to a standardized laboratory stressor (Trier Social Stress Test, TSST). Endocrine (cortisol, ACTH), immune (total IgE, leukocyte subsets) and physiological (heart rates) measures were recorded before and after the stress test. When compared to healthy controls, AD and SAR patients showed significantly higher trait anxiety (STAI) and stress vulnerability in situations characterized by failure, job overload and social conflicts (MESA). Moreover, AD subjects scored significantly lower in self-competence and self-efficacy (FKK) as well as in recreation ability (MESA). No difference trait anxiety and stress vulnerability could be detected between AD and SAR subjects. Pearson correlational analyses yielded no significant correlation between the different personality domains and the endocrine, physiological and immunological stress responses. However, stress-induced increase in eosinophil number was significantly correlated with the perceived self-competence/self-efficacy in SAR patients.

Review: Brain—immune communication psychoneuroimmunology of multiple sclerosis

The central nervous system (CNS) and the immune system are two extremely complex and highly adaptive systems. In the face of a real or anticipated threat, be it physical (eg, infection) or psychological (eg, psychosocial stress) in nature, the two systems act in concert to provide optimal adaptation to the demanding internal or environmental conditions. During instances of well being, the communication between these two systems is well tuned and balanced. However, a disturbed crosstalk between the CNS and the immune system is thought to play a major role in a wide series of disorders characterized by a hyporesponsive or hyperresponsive immune system. In multiple sclerosis (MS), a chronic inflammatory and neurodegenerative disease, an excess of inflammatory processes seems to be a hallmark and there is growing evidence for a disturbed communication between the CNS and the immune system as a crucial pathogenic factor. While the exact mechanisms for these phenomena are still poorly understood, the young discipline of psychoneuroimmunology (PNI), which focuses on the mechanism underlying the brain to immune crosstalk, might offer some insights into the existing pathogenic mechanisms. Findings from the field of PNI might also help to gain a better understanding regarding the origin and course of MS clinical symptoms such as fatigue and depression.

Altered distribution of leukocyte subsets and cytokine production in response to acute psychosocial stress in patients with psoriasis vulgaris

Psoriasis (PSO) is a mainly T helper-type 1 (TH(1)) cell mediated chronic inflammatory skin disease characterized by epidermal hyperproliferation and psoriatic plaques. There is ample evidence that stress may trigger psoriatic eruption, however, the underlying mechanisms of stress-induced exacerbation of PSO are poorly understood. The specific goal of the present study was to investigate the impact of acute stress on pathologically relevant immune functions in PSO patients. PSO patients (n=23) and healthy controls (n=25) were exposed to a standardized laboratory stressor ("Trier Social Stress Test", TSST) including a free speech and mental arithmetics in front of an audience. Blood samples were collected 10min before and 1, 10, 20, and 60min after the TSST as well as 24h after the experiment at identical time points under resting conditions. Analyses of leukocyte subsets indicated a significantly increased number of leukocyte subpopulations (lymphocytes, granulocytes, CD3(+), CD8(+), CD16(+)/CD56(+), and CD3(+)/HLA-DR(+)) after the TSST (all p<.01) with no significant between-group differences. However, monocyte number (F(3,120)=2.7; p<.01) and number of CD4(+)cells (F(3,120)=3.09; p<.05) were found to be significantly higher in PSO sufferers than in controls. Moreover, a significant decrease of CD3(+)/CD25(+)cells was observed in the PSO, but not in the control group (F(3,120)=3.46; p<.05). After exposure to the TSST, stimulation of peripheral blood mononuclear cells (PBMCs) with phytohemagglutinin (PHA) resulted in elevated production of IFN-gamma (F(3,126)=6.9; p<.001) and IL-2 (F(3,123)=6.6; p<.001), and moreover, a decreased production of IL-10 (F(3,132)=5.22; p<.01) and IL-4 (F(3,129)=3.9; p<.01). No difference in stress-induced changes of cytokine production to PHA could be identified between the two experimental groups (all p>.05). The present findings suggest that acute psychosocial stress is associated with changes of immune functions known to be involved in PSO which may be one potential explanation of how stress may trigger psoriatic eruption.