Multipath artifacts enable angular contrast in multimodal endoscopic optical coherence tomography.

Multipath artifacts are inherent to double-clad fiber based optical coherence tomography (OCT), appearing as ghost images blurred in the A-line direction. They result from the excitation of higher-order inner-cladding modes in the OCT sample arm which cross-couple into the fundamental mode at discontinuities and thus are detected in single-mode fiber-based interferometers. Historically, multipath artifacts have been regarded as a drawback in single fiber endoscopic multimodal OCT systems as they degrade OCT quality. In this work, we reveal that multipath artifacts can be projected into high-quality two-dimensional en face images which encode high angle backscattering features. Using a combination of experiment and simulation, we characterize the coupling of Mie-range scatterers into the fundamental image (LP01 mode) and higher-order image (multipath artifact). This is validated experimentally through imaging of microspheres with an endoscopic multimodal OCT system. The angular dependence of the fundamental image and higher order image generated by the multipath artifact lays the basis for multipath contrast, a ratiometric measurement of differential coupling which provides information regarding the angular diversity of a sample. Multipath contrast images can be generated from OCT data where multipath artifacts are present, meaning that a wealth of clinical data can be retrospectively examined.

Triple-clad W-type fiber mitigates multipath artifacts in multimodal optical coherence tomography.

Multimodal endoscopic optical coherence tomography (OCT) can be implemented with double-clad fiber by using the presumed single-mode core for OCT and the higher numerical aperture cladding for a secondary modality. However, the quality of OCT in double-clad fiber (DCF) based systems is compromised by the introduction of multipath artifacts that are nt present in single-mode fiber OCT systems. Herein, the mechanisms for multipath artifacts in DCF are linked to its modal contents using a commercial software package and experimental measurement. A triple-clad W-type fiber is proposed as a method for achieving multimodal imaging with single-mode quality OCT in an endoscopic system. Simulations of the modal contents of a W-type fiber are compared to DCF and single-mode fiber. Finally, a W-Type fiber rotary catheter is used in a DCF-based endoscopic OCT and autofluorescence imaging (AFI) system to demonstrate multipath artifact free OCT and AFI of a human fingertip.

Use of antipsychotics and antidepressants in first-episode psychotic depression: A nationwide register-based study.

BACKGROUND: According to guidelines, psychotic depression should be treated with both antipsychotics and antidepressants, but current practice is largely unknown. We investigated the prevalence of antipsychotic and antidepressant use in first-episode psychotic depression and factors related to antipsychotic use after the diagnosis. METHODS: We identified individuals aged 16-65 with a first-episode diagnosis of psychotic depression (ICD-10 codes F32.3, F33.3) from nationwide data linkage of Finnish healthcare and population registers during 2000-2018. Point prevalence was measured as 2-week time windows every 3 months, investigating whether the individual had a modeled drug use period ongoing during the window or not, censoring to death and end of data linkage. RESULTS: The study population included 18,490 individuals (58.0% women; mean age 39.9 years, standard deviation 14.7). The prevalence of use for antidepressants (75.0%), antipsychotics (56.4%), and both (50.0%) were highest at 3 months after the diagnosis. The prevalence declined to 51.8%, 34.1%, and 28.7%, respectively, at 3 years after the diagnosis. In a logistic regression analysis, younger age (adjusted odds ratio < 25 vs. ≥55, 0.82 [95% confidence interval 0.73-0.91]), eating disorders (0.78 [0.66-0.92]), substance use disorders (0.80 [0.73-0.87]), and occupational inactivity (0.80 [0.73-0.87]) were associated with decreased odds of using antipsychotics at 3 months after diagnosis. Increased odds were found for diagnosis from inpatient care (1.74 [1.62-1.86]), and later year of cohort entry (2010-2014 vs. 2000-2004, 1.56 [1.42-1.70]). CONCLUSION: At most, half of the individuals with newly diagnosed psychotic depression used both antidepressants and antipsychotics. This likely has a negative impact on treatment success.

Long-term thiazide use and risk of low-energy fractures among persons with Alzheimer's disease-nested case-control study.

We investigated the association between thiazide use and the risk of low-energy fractures among community dwellers with Alzheimer's disease. Longer use was associated with a decreased risk of low-energy fractures. This study extends the previous knowledge of reduced fracture risk of thiazides to persons with Alzheimer's disease. INTRODUCTION: To investigate the association between thiazide use and the risk of low-energy fractures (LEF), and hip fracture among community dwellers with Alzheimer's disease (AD). No prior study has evaluated the effect of thiazides on LEF risk of AD patients. METHODS: LEF cases were identified from the MEDALZ study, including all community-dwelling persons diagnosed with AD in Finland 2005-2011. During the follow-up from AD diagnoses until the end of 2015, cases with LEF (N = 10,416) and hip fracture (N = 5578) were identified. LEF cases were matched with up to three controls without LEF, according to time since AD diagnosis, age and gender. Thiazide use identified from the Prescription register data was modeled with PRE2DUP method. Current use was defined in 0-30 days' time window before the fracture/matching date, and duration of current use was assessed. The association between thiazide exposure and LEFs was assessed with conditional logistic regression. RESULTS: Current thiazide use was observed in 10.5% of LEF cases and 12.5% of controls. Current thiazide use was associated with a decreased risk of LEF (adjusted OR [aOR] 0.83, 95% CI 0.77-0.88). In terms of the duration of use, no association was observed with short-term use (< 1 year or 1-3 years), while longer use (> 3 years) was associated with a reduced risk of LEF (aOR 0.77, 95% CI 0.71-0.83) and hip fracture (aOR 0.68, 95% CI 0.60-0.78). CONCLUSIONS: Our study extends the previous knowledge of reduced fracture risk of thiazides to persons with AD, a population with significantly increased background risk of fractures.

The association between subjective maternal stress during pregnancy and offspring clinically diagnosed psychiatric disorders.

OBJECTIVE: Exposure to prenatal stress is a ubiquitous and non-specific risk factor for adverse outcomes in adulthood. In this study, we examined associations between exposure to subjective maternal stress during pregnancy and subsequent diagnosis of psychiatric disorders in offspring. METHOD: This study used the Helsinki Longitudinal Temperament Cohort, a prospective birth cohort of individuals born between 1 July 1975 and 30 June 1976 in Helsinki, Finland. The sample for this study comprised 3626 infants whose mothers had completed health and well-being assessments during pregnancy which included a measure of self-reported stress. We ran logistic regressions to assess potential associations between prenatal stress and offspring psychiatric disorder in adulthood, identified through the Finnish Hospital Discharge Register. RESULTS: Individuals whose mothers reported stress during pregnancy had significantly greater odds of developing a psychiatric disorder (OR = 1.41, 95% CI = 1.10-1.81) particularly a mood disorder (OR = 1.67, 95% CI = 1.10-2.54). These associations remained after adjusting for parental psychiatric history, and other prenatal factors. CONCLUSIONS: Individuals exposed to prenatal stress had significantly increased risk of developing psychiatric disorders later in life. This finding highlights the importance of supporting the mental health and emotional well-being of women during pregnancy.

Mortality in schizophrenia: 30-year nationwide follow-up study.

OBJECTIVE: Recent reports suggest that the mortality gap between persons with schizophrenia and the general population is increasing. We investigated the mortality, age at death, and causes of death among persons diagnosed with schizophrenia and the general population in Finland during 1984-2014. METHODS: All persons with schizophrenia in Finland were identified from hospital discharge register, and compared with the Finnish population aged 16 years and older during 1984-2014, based on data from Statistics Finland. Age at death and standardized mortality ratio (SMR) were calculated for each follow-up year. RESULTS: Mean age at death increased from 57.6 years in 1984 to 70.1 years in 2014 in persons with schizophrenia, and from 70.9 to 77.5 years in the general population. All-cause SMR remained stable during the follow-up (2.6 in 1984 and 2.7 in 2014). A major change was observed in SMR for suicides which decreased from 11.0 in 1984 to 6.6 in 2014 (-40%). The SMRs for cardiovascular and cancer deaths showed increasing trends. CONCLUSION: The longevity of persons with schizophrenia is improving at approximately the same rate as the general population but suicide rates have declined substantially. However, there is still a major disparity in mortality compared with general population.

The risk of Alzheimer's disease associated with benzodiazepines and related drugs: a nested case-control study.

OBJECTIVE: To assess the association between benzodiazepine and related drug (BZDR) use and risk of Alzheimer's disease (AD) with cumulative consumption and duration of use based models. METHOD: A nationwide nested case-control study of all Finnish community-dwelling persons who received clinically verified AD diagnosis in 2005-2011 (N = 70 719) and their matched controls (N = 282 862). AD diagnosis was based on DSM-IV and NINCDS-ADRDA criteria. BZDR purchases were extracted from the Prescription Register since 1995. The association between BZDR use and AD was assessed using conditional logistic regression with 5-year lag time between exposure and outcome. RESULTS: Benzodiazepine and related drug use was associated with modestly increased risk of AD (adjusted OR 1.06, 95% CI 1.04-1.08). A dose-response relationship was observed with both cumulative consumption and duration. Adjustment for other psychotropics removed the cumulative dose-response relationship by attenuating the ORs in the highest dose category. CONCLUSION: Benzodiazepine and related drug use in general was associated with modestly increased risk of AD. No major differences were observed between different subcategories of BZDRs (i.e. benzodiazepines, Z drugs, short-/medium-acting or long-acting BZDRs). As dose-response relationship abolished after adjustment for other psychotropics, it is possible that the association may partially be due to antidepressants and/or antipsychotics, or concomitant use of these medications.

Comparative effectiveness of mood stabilizers and antipsychotics in the prevention of hospitalization after lithium discontinuation in bipolar disorder.

The aim of the study was to compare the real-world effectiveness of mood stabilizers and antipsychotics in the prevention of psychiatric hospitalizations and treatment failure after lithium discontinuation in a nationwide bipolar cohort. Using health-care registers, we identified everyone in Finland diagnosed with bipolar disorder during 1987-2018 who discontinued lithium after using it for at least one year (n = 4 052, median period of lithium use before discontinuation 2.7 years). The risk of psychiatric hospitalization and treatment failure (psychiatric hospitalization, death or change in medication) were investigated with within-individual Cox regression. Of mood stabilizer monotherapies, the periods of valproate use (HR = 0.83, 95% CI = 0.71 - 0.97) had lower risk of hospitalization than nonuse of mood stabilizers. Of antipsychotic monotherapies, the use of long-acting injectable (LAI) antipsychotics (HR = 0.48, 95% CI = 0.26 - 0.88) and chlorprothixene (HR = 0.62, 95% CI = 0.44 - 0.88) were associated with lower risk and the use of quetiapine (HR = 1.26, 95% CI = 1.07 - 1.48) and oral olanzapine (HR = 1.23, 95% CI = 1.01 - 1.49) with higher risk of psychiatric hospitalizations than nonuse of antipsychotics. Of mood stabilizer monotherapies, lithium use was associated with lower risk of treatment failure (HR = 0.82, 95% CI = 0.76 - 0.88) than valproate use. The results suggest that antipsychotic LAIs are especially effective in the prevention of psychiatric hospitalizations after lithium discontinuation. The need to alter used medications may be the lowest when lithium is restarted.

Trajectories of labour market marginalisation among young adults with newly diagnosed attention-deficit/hyperactivity disorder (ADHD).

AIMS: Labour market marginalisation (LMM), i.e. severe problems in finding and keeping a job, is common among young adults with attention-deficit/hyperactivity disorder (ADHD). This study aimed to disentangle the extent of LMM as well as the heterogeneity in patterns of LMM among young adults with ADHD and what characterises those belonging to these distinct trajectories of LMM. METHODS: This population-based register study investigated all 6287 young adults, aged 22-29 years, who had their first primary or secondary diagnosis of ADHD in Sweden between 2006 and 2011. Group-based trajectory (GBT) models were used to estimate trajectories of LMM, conceptualised as both unemployment and work disability, 3 years before and 5 years after the year of an incident diagnosis of ADHD. Odds ratios (ORs) with 95% confidence intervals (CIs) for the association between individual characteristics and the trajectory groups of LMM were estimated by multinomial logistic regression. RESULTS: Six distinct trajectories of LMM were found: 'increasing high' (21% belonged to this trajectory group) with high levels of LMM throughout the study period, 'rapidly increasing' (19%), 'moderately increasing' (21%), 'constant low' (12%) with low levels of LMM throughout the study period, 'moderately decreasing' (14%) and finally 'fluctuating' (13%), following a reversed u-shaped curve. Individuals with the following characteristics had an increased probability of belonging to trajectory groups of increasing LMM: low educational level (moderately increasing: OR: 1.4; CI: 1.2-1.8, rapidly increasing: OR: 1.7; CI: 1.3-2.1, increasing high: OR: 2.9; CI: 2.3-3.6), single parents (moderately increasing: OR: 1.6; CI: 1.1-2.4, rapidly increasing: OR: 2.0; CI: 1.3-3.0), those born outside the European Union/the Nordic countries (rapidly increasing: OR: 1.7; CI: 1.1-2.5, increasing high: OR: 2.1; CI: 1.4-3.1), persons living in small cities/villages (moderately increasing: OR: 2.4; CI: 1.9-3.0, rapidly increasing: OR: 2.1; CI: 1.6-2.7, increasing high: OR: 2.6; CI: 2.0-3.3) and those with comorbid mental disorders, most pronounced regarding schizophrenia/psychoses (rapidly increasing: OR: 6.7; CI: 2.9-19.5, increasing high: OR: 12.8; CI: 5.5-37.0), autism spectrum disorders (rapidly increasing: OR: 4.6; CI: 3.1-7.1, increasing high: OR: 9.6; CI: 6.5-14.6), anxiety/stress-related disorders (moderately increasing: OR: 1.3; CI: 1.1-1.7, rapidly increasing: OR: 2.0; CI: 1.6-2.5, increasing high: OR: 1.8; CI: 1.5-2.3) and depression/bipolar disorder (moderately increasing: OR: 1.3; CI: 1.0-1.6, rapidly increasing: OR: 1.7; CI: 1.4-2.2, increasing high: OR: 1.5; CI: 1.2-1.9). CONCLUSIONS: About 61% of young adults were characterised by increasing LMM after a diagnosis of ADHD. To avoid marginalisation, attention should especially be given to young adults diagnosed with ADHD with a low educational level, that are single parents and who are living outside big cities. Also, young adults with comorbid mental disorders should be monitored for LMM early in working life.

Detection of medications associated with Alzheimer's disease using ensemble methods and cooperative game theory.

OBJECTIVE: To study the feasibility of evaluating feature importance with Shapley Values and ensemble methods in the context of pharmacoepidemiology and medication safety. METHODS: We detected medications associated with Alzheimer's disease (AD) by examining the additive feature attribution with combined approach of Gradient Boosting and Shapley Values in the Medication use and Alzheimer's disease (MEDALZ) study, a nested case-control study of 70,719 verified AD cases in Finland. Our methodological approach is to do binary classification using Gradient boosting (an ensemble of weak classifiers) in a supervised learning manner. Then we apply Shapley Values (from cooperative game theory) to analyze how feature combinations affect the classification result. Medication use with a five to one year time-window before AD diagnosis was ascertained from Prescription register. RESULTS: Antipsychotics with low or medium dose, antidepressants with medium to high dose, and cardiovascular medications with medium to high dose were identified as the contributing features for separating cases with AD from controls. Medium to high amount of irregularity in the purchase pattern were an indicating feature for separating AD cases from controls. The similarity of medication purchases between AD cases and controls made the feature evaluation challenging. CONCLUSIONS: The combined approach of Gradient Boosting and feature evaluation with Shapley Values identified features that were consistent with findings from previous hypothesis-driven studies. Additionally, the results from the additive feature attribution identified new candidates for future studies on AD risk factors. Our approach also shows promise for studies based on observational studies, where feature identification and interactions in populations are of interest; and the applicability of using Shapley Values for evaluating feature relevance in pattern recognition tasks.

Iron-Terephthalate Coordination Network Thin Films Through In-Situ Atomic/Molecular Layer Deposition.

Iron terephthalate coordination network thin films can be fabricated using the state-of-the-art gas-phase atomic/molecular layer deposition (ALD/MLD) technique in a highly controlled manner. Iron is an Earth-abundant and nonhazardous transition metal, and with its rich variety of potential applications an interesting metal constituent for the inorganic-organic coordination network films. Our work underlines the role of the metal precursor used when aiming at in-situ ALD/MLD growth of crystalline inorganic-organic thin films. We obtain crystalline iron terephthalate films when FeCl3 is employed as the iron source whereas depositions based on the bulkier Fe(acac)3 precursor yield amorphous films. The chemical composition and structure of the films are investigated with GIXRD, XRR, FTIR and XPS.

Proton pump inhibitor use and risk of hip fractures among community-dwelling persons with Alzheimer's disease-a nested case-control study.

BACKGROUND: Hip fractures are a major health concern among older persons with Alzheimer's disease, who usually use many concomitant drugs for several diseases. Evidence of the association between proton pump inhibitor use and risk of hip fracture is contradictory. AIM: To investigate whether the long-term use of proton pump inhibitor is associated with risk of hip fractures among community-dwelling persons with Alzheimer's disease. METHODS: In this nested case-control study, the nationwide MEDALZ data were utilised. Community-dwelling persons with Alzheimer's disease who encountered incident hip fracture (N = 4818; mean age 84.1) were included as cases. Four controls were matched for each case at the date of hip fracture (N = 19 235; mean age 84.0). The association between hip fracture and duration of current PPI use (ongoing use during 0-30 days before the index date), and cumulative duration of use during 10 years before was investigated with conditional logistic regression. RESULTS: Long-term or cumulative proton pump inhibitor use was not associated with an increased risk of hip fracture. Current proton pump inhibitor use was associated with an increased risk of hip fracture (adjusted OR 1.12, 95% CI 1.03-1.22). The risk was increased in short-term current use (<1 year) (adjusted OR 1.23, 95% CI 1.10-1.37). CONCLUSIONS: The increased risk of hip fracture was evident only in short-term proton pump inhibitor use, but no association was found for long-term or cumulative use. Thus, our findings do not support previous assumptions that long-term proton pump inhibitor use would be associated with an increased risk of hip fractures.

Differences in analgesic use in community-dwelling persons with and without Alzheimer's disease.

BACKGROUND: There are conflicting findings about analgesic use among persons with cognitive impairment compared to cognitively intact older persons. The objective of our study was to investigate the prevalence of analgesic use in community-dwelling persons with and without Alzheimer's disease (AD), within six months after AD diagnosis and to find out factors associated with the use of analgesics and specific analgesic groups. METHOD: We utilized data from register based MEDALZ (Medication use and Alzheimer's disease) cohort consisting of all community-dwelling persons diagnosed with AD during 2005-2011 in Finland and their matched comparison persons without AD. Altogether, 67,215 persons with AD and one comparison person for each case were included. Drug use data were collected from the Prescription Register and comorbidities from Special Reimbursement and Hospital Discharge Registers. RESULTS: Statistically significant (p < 0.001) yet mostly small differences were found for analgesics use: analgesics were used by 34.9% and 33.5% of persons with and without AD, respectively. Paracetamol was the most frequently used analgesic both among persons with (25.0%) and without AD (19.1%). Persons with AD used less frequently NSAIDs (Nonsteroidal Anti-inflammatory Drugs) (13.2% vs. 17.3%) and mild opioids (5.0% vs. 7.1%), while the use of strong opioids was more common in comparison to persons without AD (1.3% vs. 1.1%, respectively). Analgesic users were more likely women, aged ≥80 years, had asthma/COPD, cardiovascular disease, diabetes, cancer, hip fracture, osteoporosis, rheumatoid arthritis, and lower socioeconomic position. CONCLUSION: Further studies are needed to evaluate the adequateness of pain relief in older persons with and without AD. SIGNIFICANCE: Persons with Alzheimer's disease (AD) used more frequently paracetamol and less frequently NSAIDs and mild opioids. A decreasing trend of NSAID use was observed among persons with AD during the study period.

Incidence of cancer among persons with schizophrenia and their relatives.

BACKGROUND: It has repeatedly been reported that the risk for cancer in patients with schizophrenia is different from that of the general population, specifically a lower risk for lung cancer despite increased smoking. Confirmation of these associations could lead to hypotheses on shared risk or protective factors, either genetic or environmental. METHODS: From Finland's National Hospital Discharge and Disability Pension registers, Helsinki, we identified a cohort of 26 996 individuals born between 1940 and 1969 and treated for schizophrenia between 1969 and 1991. They were followed up for cancer from 1971 to 1996 by record linkage with the Finnish Cancer Registry, yielding 446 653 person-years at risk, and standardized incidence ratios (SIRs) were calculated. Likewise, 39 131 parents and 52 976 siblings of the patients with schizophrenia were followed up to explore familial genetic hypotheses on deviations in cancer risk. RESULTS: In patients with schizophrenia, an increased overall cancer risk was found (724 cases observed vs 619 expected; SIR, 1.17; 95% confidence interval [CI], 1.09-1.25). Half of the excess cases were attributable to lung cancer (SIR, 2.17; 95% CI, 1.78-2.60), and the strongest relative increase in risk was in pharyngeal cancer (SIR, 2.60; 95% CI, 1.25-4.77). Cancer incidence in siblings (SIR, 0.89; 95% CI, 0.83-0.94) and parents (SIR, 0.91; 95% CI, 0.89-0.93) was consistently lower than that in the general population. CONCLUSION: Although specific lifestyle factors, particularly tobacco smoking and alcohol consumption, probably account for the increased cancer risk in patients with schizophrenia, the decreased risk in relatives would be compatible with a postulated genetic risk factor for schizophrenia offering selective advantage to unaffected relatives.

Decline in the incidence of schizophrenia in Finnish cohorts born from 1954 to 1965.

BACKGROUND: The declining incidence of schizophrenia observed in several countries is believed by many to merely reflect methodological problems in the studies performed. We report the first nationwide historical cohort study of changes in the incidence of schizophrenia, in which many of the previous methodological problems were overcome. METHODS: We used the Finnish Population Register to identify everyone born in Finland from 1954 to 1965. These persons were followed up from their 16th to their 26th birthdays, and all cases of schizophrenia (International Classification of Diseases, Eighth Revision and International Classification of Diseases, Ninth Revision code 295) that emerged were identified from the National Hospital Discharge Register, the Pension Register, and the Free Medicine Register. Persons for whom an age of onset could be defined were included in the analyses (n = 5645). We used the Poisson regression model to estimate the effects of age, sex, birth cohort, period of diagnosis, and season of birth on the incidence of schizophrenia. The relative importance of cohort and period were assessed using an age-period-cohort model. RESULTS: The incidence declined significantly in each successive cohort, from 0.79 to 0.53 per 1000 among males and from 0.58 to 0.41 per 1000 among females. The effects of cohort and period on the change were both significant. CONCLUSIONS: The incidence of schizophrenia has declined in Finland. This was partly caused by confounding factors, as reflected in the significant period effect. The significant birth cohort effect suggests that the intensity or frequency of one or more risk factors for schizophrenia has decreased.

School performance in Finnish children and later development of schizophrenia: a population-based longitudinal study.

BACKGROUND: We examined whether children who are diagnosed as having schizophrenia in adulthood could be distinguished from their peers on performance in elementary school. METHODS: We used a case-control study design nested within a population-based birth cohort of all individuals born in Helsinki, Finland, between January 1, 1951, and December 31, 1960. Case ascertainment was from 3 national health care registers. Elementary school records were obtained for 400 children who were diagnosed as having schizophrenia in adulthood and for 408 controls. Results were analyzed for the 4 years of schooling (ages 7-11 years) that were common to all pupils. School subjects were entered into a principal components analysis and produced 3 factors: academic, nonacademic, and behavioral. These factors were compared between cases and controls after adjusting for sex and social group. Eligibility for high school and progression to high school were investigated among cases and controls. RESULTS: Cases performed significantly worse than controls only on the nonacademic factor (which loaded sports and handicrafts). There were no differences between the groups on the academic or behavioral factors, and there were no significant clinical correlates of factor scores. Cases were significantly less likely than controls to progress to high school, despite similar eligibility. CONCLUSIONS: Poor performance in sports and handicrafts during elementary school, which may indicate a motor coordination deficit, appears to be a risk factor for later schizophrenia. Poor academic performance in elementary school was not a risk factor for schizophrenia in this study. Lack of expected progression to high school among cases, despite good academic grades, provides evidence for deteriorating premorbid functional adjustment in schizophrenia.

Iron-based inorganic-organic hybrid and superlattice thin films by ALD/MLD.

Here we present novel layer-by-layer deposition processes for the fabrication of inorganic-organic hybrid thin films of the (-Fe-O-C6H4-O-)n type and also superlattices where thicker iron oxide layers alternate with monomolecular-thin organic layers. The processes are based on a combination of atomic layer deposition (ALD) and molecular layer deposition (MLD) techniques where the cyclopentadienyl iron dicarbonyl dimer (Cp2Fe2(CO)4) is used as the iron source and hydroquinone (HQ) as the organic precursor. For the (-Fe-O-C6H4-O-)n hybrid films a growth rate value as high as 3.7 Å per cycle was achieved at 180 °C. Superlattices where thin crystalline iron oxide layers of the magnetite structure alternate with single organic layers consisting of benzene rings were moreover successfully fabricated from the same precursors at 160 °C using water as the source of oxygen in the ALD cycles for the magnetite layers. We foresee that our new ALD/MLD processes offer a valuable novel tool to modify the properties of magnetite thin films and even more widely possess the potential to boost the ALD/MLD research frontier on functional transition metal oxide based thin films.

Sotalol prolongation of the QTc interval in hypertensive patients.

The effect of oral sotalol on the heart rate-corrected AT interval (QTc) was studied in 33 hypertensive patients. Sotalol given once daily in doses of 160 to 640 mg prolonged in QTc interval in a concentration-dependent manner by up to 150 msec (P less than 0.001) over presotalol levels. The prolongation did not correlate with the initial length of the QTc interval. In seven patients with sotalol-prolonged QTc interval, the withdrawal of sotalol for 3 days shortened the interval to nearly its original length. The effect of sotalol of PQ and QRS times was minimal. Sotalol seems to differ from other beta antagonists in having clear amiodarone-like effects on the action potential of the heart after short- and long-term administration. The measuring of the QTc interval is recommended if high school concentrations are expected, since the risk of cardiac arrhythmias may increase.

Association between prenatal exposure to poliovirus infection and adult schizophrenia.

OBJECTIVE: The authors' goal was to determine whether there is an association between prenatal exposure to poliovirus infection and later development of schizophrenia. METHOD: All Finnish patients born between 1951 and 1969 with discharge diagnoses of schizophrenia (N = 13,559) were identified from the Finnish Hospital Discharge Register. Information on the monthly number of cases of paralytic poliomyelitis was obtained for each province in Finland. The authors analyzed the incidence of births of individuals who later developed schizophrenia by using a Poisson regression model with year and place of birth, age, sex, season of birth, and smoothed incidence of poliomyelitis in different gestational periods as explanatory variables. RESULTS: An association between the incidence of poliomyelitis and the incidence of births 5 months later of individuals who later developed schizophrenia was observed. Without controlling for seasonality, the effect was significant throughout the second trimester. CONCLUSIONS: Second-trimester exposure to poliovirus infection may increase the risk for the later development of schizophrenia.

High serum cholesterol and risk of suicide.

OBJECTIVE: The study was conducted to estimate the association between serum total cholesterol concentration and mortality from suicide. METHOD: The baseline serum total cholesterol concentration of 37,635 adults was determined in five independent population surveys conducted during 1972-1992 in Finland. Mortality from different causes of death was monitored for a mean of 14.6 years after the survey dates. The means for violent suicides (N=130) included hanging, firearms, cutting, jumping, and unspecified means. The means for nonviolent suicides (N=46) included drug overdose, poisoning with gases, and drowning. RESULTS: Serum total cholesterol concentration was positively related to the risk of violent suicide. Among subjects whose serum total cholesterol concentration was in the highest category, the adjusted relative risk was more than twofold compared with the lowest category. The violent/nonviolent suicide ratio increased linearly with increasing cholesterol category. No association between serum total cholesterol concentration and the risk of nonviolent suicide was found. CONCLUSIONS: This is the first study to demonstrate the positive relationship of high serum total cholesterol concentration with increased risk of violent suicide.