Effects of SSRI treatment on GABA and glutamate levels in an associative relearning paradigm.

Impaired cognitive flexibility represents a widespread symptom in psychiatric disorders, including major depressive disorder (MDD), a disease, characterized by an imbalance of neurotransmitter concentrations. While memory formation is mostly associated with glutamate, also gamma-Aminobutyric acid (GABA) and serotonin show attributions in a complex interplay between neurotransmitter systems. Treatment with selective serotonin reuptake inhibitors (SSRIs) does not solely affect the serotonergic system but shows downstream effects on GABA- and glutamatergic neurotransmission, potentially helping to restore cognitive function via neuroplastic effects. Hence, this study aims to elaborate the effects of associative relearning and SSRI treatment on GABAergic and glutamatergic function within and between five brain regions using magnetic resonance spectroscopy imaging (MRSI). In this study, healthy subjects were randomized into four groups which underwent three weeks of an associative relearning paradigm, with or without emotional connotation, under SSRI (10mg escitalopram) or placebo administration. MRSI measurements, using a spiral-encoded, 3D-GABA-edited MEGA-LASER sequence at 3T, were performed on the first and last day of relearning. Mean GABA+/tCr (GABA+ = GABA + macromolecules; tCr = total creatine) and Glx/tCr (Glx = glutamate + glutamine) ratios were quantified in a ROI-based approach for the hippocampus, insula, putamen, pallidum and thalamus, using LCModel. A total of 66 subjects ((37 female, mean age ± SD = 25.4±4.7) for Glx/tCr and 58 subjects (32 female, mean age ± SD = 25.1±4.7) for GABA+/tCr were included in the final analysis. A significant measurement by region and treatment (SSRI vs placebo) interaction on Glx/tCr ratios was found (pcor=0.017), with post hoc tests confirming differential effects on hippocampus and thalamus (pcor=0.046). Moreover, treatment by time comparison, for each ROI independently, showed a reduction of hippocampal Glx/tCr ratios after SSRI treatment (puncor=0.033). No significant treatment effects on GABA+/tCr ratios or effects of relearning condition on any neurotransmitter ratio could be found. Here, we showed a significant SSRI- and relearning-driven interaction effect of hippocampal and thalamic Glx/tCr levels, suggesting differential behavior based on different serotonin transporter and receptor densities. Moreover, an indication for Glx/tCr adaptions in the hippocampus after three weeks of SSRI treatment could be revealed. Our findings are in line with animal studies reporting glutamate adaptions in the hippocampus following chronic SSRI intake. Due to the complex interplay of serotonin and hippocampal function, involving multiple serotonin receptor subtypes on glutamatergic cells and GABAergic interneurons, the interpretation of underlying neurobiological actions remains challenging.

Facial emotion recognition in patients with subjective cognitive decline and mild cognitive impairment.

BACKGROUND: Deficits in facial emotion recognition (FER) have been shown to substantially impair several aspects in everyday life of affected individuals (e.g. social functioning). Presently, we aim at assessing differences in emotion recognition performance in three patient groups suffering from mild forms of cognitive impairment compared to healthy controls. METHODS: Performance on a concise emotion recognition test battery (VERT-K) of 68 patients with subjective cognitive decline (SCD), 44 non-amnestic (non-aMCI), and 25 amnestic patients (aMCI) with mild cognitive impairment (MCI) was compared with an age-equivalent sample of 138 healthy controls all of which were recruited within the framework of the Vienna Conversion to Dementia Study. Additionally, patients and controls underwent individual assessment using a comprehensive neuropsychological test battery examining attention, executive functioning, language, and memory (NTBV), the Beck Depression Inventory (BDI), and a measure of premorbid IQ (WST). RESULTS: Type of diagnosis showed a significant effect on emotion recognition performance, indicating progressively deteriorating results as severity of diagnosis increased. Between-groups effect sizes were substantial, showing non-trivial effects in all comparisons (Cohen's ds from -0.30 to -0.83) except for SCD versus controls. Moreover, emotion recognition performance was higher in women and positively associated with premorbid IQ. CONCLUSIONS: Our findings indicate substantial effects of progressive neurological damage on emotion recognition in patients. Importantly, emotion recognition deficits were observable in non-amnestic patients as well, thus conceivably suggesting associations between decreased recognition performance and global cognitive decline. Premorbid IQ appears to act as protective factor yielding lesser deficits in patients showing higher IQs.

[Screening for cancer]. / Screening für Krebserkrankungen.

A low birth rate in addition to an increasing life expectancy within the context of an aging population characterize the current demographic situation in Germany. Cancer is primarily a disease of old age and the frequency increases with an expanding older population. In 2013, cancer was the second most common cause of death in Germany. With the aid of screening examinations cancer should be detected in the early stages so that suitable therapeutic measures can be initiated. In Germany, screening is currently offered for breast, cervical, colorectal, skin and prostate cancer and is covered by the statutory health insurance. Mammography screening is the only organized screening program in Germany. Eligible women are regularly invited to attend this program, which is not the case for the other types of cancer screening. In accordance with the Cancer Screening and Registry Act (KFRG) of 2013, colorectal and cervical cancer screening will also be implemented as organized screening programs in the future. As is the case in the mammography screening program, those eligible to participate will receive an invitation letter and the new programs are to be continually monitored, documented and evaluated.

Subjective memory complaints, depressive symptoms and cognition in Parkinson's disease patients.

BACKGROUND AND PURPOSE: The goal of this study was to establish the prevalence of subjective memory complaints (SMCs) and depressive symptoms (DS)s and their relation to cognitive functioning in patients with Parkinson's disease (PD). METHODS: In all, 248 controls and 104 PD patients were included in the study. The PD group was subdivided into three PD subtypes with mild cognitive impairment (MCI) according to the Petersen criteria and three PD subtypes with MCI according to the Litvan criteria. RESULTS: Substantial SMCs were reported by 7.7% of controls and 16.3% of the PD patients (P < 0.001). A clinically relevant degree of DSs was evident in 16.6% of controls compared with 40.4% in the PD group (P < 0.001). An analysis of variance revealed a statistically significant difference for SMCs across all Petersen groups as well across all Litvan groups. Two-factor analyses of variance with the factors cognitive status (MCI subtype) and depressive state (depressed versus not depressed) and SMCs as dependent variable revealed significant results. CONCLUSIONS: Approximately 15% of PD patients seeking help in a movement disorder clinic report significant SMCs, with an increasing degree from cognitively healthy PD to PD-MCI. Significant DSs increase SMCs across all cognitive status groups.

Subjective memory complaints, depressive symptoms and cognition in patients attending a memory outpatient clinic.

BACKGROUND: The goals of this study were to establish prevalence of subjective memory complaints (SMC) and depressive symptoms (DS) and their relation to cognitive functioning and cognitive status in an outpatient memory clinic cohort. METHODS: Two hundred forty-eight cognitively healthy controls and 581 consecutive patients with cognitive complaints who fulfilled the inclusion criteria were included in the study. RESULTS: A statistically significant difference (p < 0.001) between control group and patient group regarding mean SMC was detected. 7.7% of controls reported a considerable degree of SMC, whereas 35.8% of patients reported considerable SMC. Additionally, a statistically significant difference (p < 0.001) between controls and patient group regarding Beck depression score was detected. 16.6% of controls showed a clinical relevant degree of DS, whereas 48.5% of patients showed DS. An analysis of variance revealed a statistically significant difference across all four groups (control group, SCI group, naMCI group, aMCI group) (p < 0.001). Whereas 8% of controls reported a considerable degree of SMC, 34% of the SCI group, 31% of the naMCI group, and 54% of the aMCI group reported considerable SMC. A two-factor analysis of variance with the factors cognitive status (controls, SCI group, naMCI group, aMCI group) and depressive status (depressed vs. not depressed) and SMC as dependent variable revealed that both factors were significant (p < 0.001), whereas the interaction was not (p = 0.820). CONCLUSIONS: A large proportion of patients seeking help in a memory outpatient clinic report considerable SMC, with an increasing degree from cognitively healthy elderly to aMCI. Depressive status increases SMC consistently across groups with different cognitive status.

[Early detection of cervical cancer in Germany: evidence and implementation]. / Früherkennung des Zervixkarzinoms in Deutschland : Evidenz und Umsetzung.

Cervical cancer is the third most common cancer among women worldwide, with an estimated 529,000 new cases in 2008. The incidence of cervical cancer in Germany is still among the highest in Western Europe. For more than 40 years women in Germany have had legal and free access to a conventional cytologic smear test starting at the age of 20 years. The introduction of the Pap smear subsequently led to a reduction in the incidence and mortality of cervical cancer. However, the low sensitivity of the Pap smear and the evidence regarding human papillomavirus (HPV) in the context of cervical cancer have led to a critical view of the existing early detection of cervical cancer. In the meantime, new screening methods have been developed and different HPV tests, liquid-based cytology, and novel biomarkers have become available. Several randomized studies have investigated HPV testing as a primary cervical cancer screening test, generating a large body of evidence. It is expected that a combination of HPV testing and cytology will improve cervical cancer screening. In the near future, the early detection of cervical cancer in Germany will be restructured on the basis of the German National Cancer Plan as well as the new Cancer Screening and Registers Act (KFRG). The European guidelines for quality assurance in cervical cancer screening will be taken into account, and an organized, population-based, and quality-assured cervical cancer screening program will be implemented.

HPV infection awareness and self-reported HPV vaccination coverage in female adolescent students in two German cities.

Low levels of human papillomavirus (HPV) awareness and knowledge have been observed in the few studies conducted among school-going adolescents. Such data are lacking in Germany. To assess awareness of HPV and of vaccination status among girls attending grades 8-13 in Bremen and Bremerhaven, two German cities. Participants completed a questionnaire in school including questions on demographic characteristics, about HPV awareness and on vaccination status. We analysed the relationship between awareness of HPV, of vaccination status and vaccine uptake and several variables including age and migrant background using univariate and multivariate logistic regression. Six hundred and thirty-two girls aged 12-20 years completed the questionnaire. 50 % had no awareness of HPV, 12 % reported being vaccinated against HPV and 57 % did not know whether or not they were vaccinated against HPV. In multivariate analyses, ever had sex was associated with awareness of HPV, and ever been to a gynaecologist with awareness of vaccination status. Our results may be an indication that female adolescents in Germany are not adequately informed and counselled about HPV and associated issues.

[Comparison of ICD coding between mortality statistics and study-intern retrospective re-coding]. / Vergleich von ICD-Kodierungen zwischen Mortalitätsstatistik und studieninterner retrospektiver Nachkodierung.

OBJECTIVES: The aim of this study was to assess agreement between study-intern nosologist death certificate coding and official mortality statistics ICD codes. METHODS: During the follow-up of a historical cohort study conducted in Germany, original death certificates were obtained for deceased cohort members and ICD coded by a study-intern nosologist. Additionally, ICD codes for these study subjects were obtained from a state statistical office responsible for mortality statistics. A weighted inter-observer agreement for these two sources was calculated. RESULTS: In total, 406 ICD codes were available from both sources. 219 (53.9%) of these ICD codes completely agreed on the highest level possible (three- or four-digits). Agreement was found on the three-digit level with a difference at the fourth digit in 42 (10.3%) causes of death. Agreement within diagnosis groups or within chapters of disease was found in 21 (5.2%) and 49 (12.1%) causes of death, respectively. The weighted kappa for the overall inter-observer agreement was 0.67 [95% confidence interval (CI): 0.63-0.71]. Within chapters of disease, agreement was higher for neoplasms (kappa=0.88; 95% CI: 0.83-0.93) than for cardiovascular diseases (kappa=0.69; CI: 0.62-0.76). CONCLUSIONS: Overall level of agreement between the two coding sources was not very good. In Germany, the quality of coding has not improved substantially in the past two decades. The introduction of automatic coding systems, multicausal coding and a mortality register could improve the quality of ICD coding in Germany.

[Right-sided lower abdominal pain after appendectomy?]. / Rechtsseitige Unterbauchschmerzen nach Appendektomie?

A young male patient presented with right lower quadrant abdominal pain 3 years after laparoscopic appendectomy. Clinical and radiological findings were in keeping with acute appendicitis and the diagnosis of stump appendicitis could be confirmed by laparoscopy. This case serves as a reminder of this differential diagnosis and to discuss therapy and prevention of this rare condition.

Whole embryo culture: an important tool in developmental toxicology today.

The number of candidate chemicals or drugs for registration and authorization is increasing at a fast rate and only few of the existing substances have been tested for teratogenicity to date. Therefore, there is high pressure on authorities to accept models like the whole embryo culture as a screening system for safety evaluation procedures. In view of this background the gradual development of the whole embryo culture into a standardized, scientifically validated tool for developmental toxicology during the last 70 years is summarized. The methodological development of the culture technique is described with the completion, improvement and refinement of the basic culture method as main intention. Special attention was paid to different culture techniques, culture media, gassing schedules, and evaluation strategies. Furthermore the importance of taking "in vitro pharmacokinetics" into consideration when a comparison of in vitro/in vivo results from embryotoxicity testing is intended, is stressed. Additionally, the demonstration of the broad spectrum of useful scientific applications when using this culture system in combination with sophisticated analytical techniques is demonstrated. Finally, an overview on different strategies for the validation of this culture system as an in vitro embryo toxicity test is provided and the officially accepted formal validation process for this application is summarized. The successful validation makes the whole embryo culture a complex in vitro embryotoxicity test with high accuracy and predictability. This robust in vitro system modelling the main phase of rodent organogenesis with a high reproducibility is valuable enough to attract special attention in related scientific fields.

TP53 polymorphism, HPV infection, and risk of cervical cancer.

The role of a polymorphism at position 72 of the tumor suppressor gene TP53 in the development of cervical cancer is not well established. The arginine variant of the p53 protein could be more susceptible to degradation by human papillomavirus (HPV) E6 protein than the protein containing proline. Recent studies show controversial results. We investigated a possible association between TP53 polymorphism and cervical cancer in a Peruvian population with high prevalence of HPV infection. HPV status and TP53 polymorphism were determined for 119 cases of invasive cervical cancer and 127 control women from Peru. HPV infection was detected by PCR of cervical cells or tumor biopsies. For determination of TP53 polymorphism, exon 4 of the TP53 gene was amplified by PCR, and DNA was subsequently subjected to restriction enzyme digest. Associations between TP53 polymorphism, HPV infection, and cervical cancer were assessed using logistic regression. Women homozygotes for arginine had a 2.2-fold increased risk (95% confidence interval: 0.6-7.6) for cervical cancer. The odds ratio for women heterozygotes for Arg/Pro was 3.5 (95% confidence interval: 0.9-14). Similarly increased risks were found when restricting analysis to HPV-positive women only. The distribution of TP53 genotypes in this Peruvian population was comparable with that found in Caucasians. Our results cannot rule out an association between the TP53 polymorphism at codon 72, HPV infection, and the etiology of cervical cancer.

Results of in vivo and in vitro studies for assessing prenatal toxicity.

Examples of a combined approach using in vivo as well as in vitro methods for the assessment of prenatal toxicity are presented. The topics discussed include the analysis of the possible embryotoxic potential of valproic acid (VPA), female sex hormones, bis(tri-n-butyltin) oxide (TBTO), and acyclovir and the problem of supplementing in vitro systems with drug-metabolizing activity.

The lack of effects of nonthermal RF electromagnetic fields on the development of rat embryos grown in culture.

Rat embryos (9.5 days old) were exposed for up to 36 h to various radio frequency (RF) electric and magnetic fields (modulation frequency: 16, 60, 120 Hz; electric field strength: 60, 600 V/m; magnetic induction: 0.2, 2.0 microT). A resonator technique was used to generate standing waves thus fulfilling three conditions: The site of maximum electric and magnetic oscillations could be separated, the field strengths were known exactly and a high homogeneity over the sample volume was achieved. In each frequency region the transmitter power levels were set to give specific absorption rate (SAR) values spreading from far below to far above the values met in the field of telecommunication (0.2, 1.0 and 5.0 W/kg). The criteria used to examine the embryos on day 11.5 for possible structural effects consisted of a scoring system, photographs, histology using both light and electron microscopy and determination of the protein content. All these data have been taken as sets of different intermediate frequency (IF) amplitude modulation of the RF carriers. Neither the electric nor the magnetic fields tested interfered significantly with the normal growth and differentiation of the embryos in vitro.

Whole embryo culture: interpretation of abnormal development in vitro.

An overview will be given of a number of problems that arise when we attempt an interpretation of data obtained with the whole embryo culture method (WEC). The following aspects will be considered: 1) Types of deviation from normal development in the whole-embryo culture system: (a) problem of "artifacts" (for example, due to preparation mistakes and suboptimal culture conditions), (b) types and frequency of abnormal development in controls, retardation as an abnormal outcome, and the difficulty of assessing its significance, (c) gross-structural defects and, specifically, attempts to answer the following questions: (i) What are the limitations for an assessment of abnormal development with the WEC? (ii) Is a specific abnormality pattern recognizable under specific pathologic conditions? (iii) Is the rate of induced abnormal development concentration-dependent? (2) Problems encountered when interpreting concentration-effect relationships (for example, statistical and pharmacokinetic aspects). (3) Necessity of verifying in vitro effects with in vivo studies.

Significance of embryo culture methods for studying the prenatal toxicity of virustatic agents.

Culture methods have become important tools for elucidating the prenatal toxicity of drugs and other xenobiotics. In this paper we will review how we used in vitro as well as in vivo approaches to demonstrate the teratogenic potential of aciclovir and other related virustatic agents. In addition, some new data on this topic will be given. The teratogenic potential of the virustatic agent aciclovir was not recognized in routinely performed segment-II-studies, but the first indication came from experiments with the culture of rat embryos. Subsequently, the findings were confirmed in modified in vivo tests and it became clear that out of a group of six related drugs aciclovir exhibited the highest potential for prenatal toxicity. The effects of aciclovir on limb development were not pronounced--this has been shown with in vitro and in vivo experiments as well. In vivo experiments first indicated that the prenatal development of the thymus is disturbed by aciclovir. This effect was further studied with the culture of fetal thymuses and again the effect of aciclovir could be compared with related drugs. In summary, our work with virustatics during the last years has shown that in vivo and in vitro approaches are by no means competitive and that a combination of both approaches can provide a solid basis for a toxicologic evaluation.

The use of whole embryo culture to elucidate teratogenic mechanisms.

In the overview presented, only selected examples for the applicability of whole embryo culture, and a few examples for its use and possible misuse, are mentioned. In general, the system has proved suitable for elucidating mechanisms involved in abnormal development at this embryonic stage. However, it should be remembered that only a small window of prenatal development can be judged with this technique, and that the system is not well suited for elucidating many special effects and abnormalities induced at later stages of development. For this reason, no single in vitro system is suitable to study all kinds of problems in prenatal biology or toxicology. As emphasized before, the real significance of the whole embryo culture technique rests on the variety of methodological possibilities that can be modified by any creative scientist. In connection with in vivo and appropriate pharmacokinetic studies, this system will play an important role in the field of developmental biology and toxicology in the future.

Pharmacokinetic aspects of drug effects in vitro (II) placental transfer to the embryo and activity of some carboxylic acids structurally related to valproic acid in whole embryos in culture.

The transfer of a group of short/medium chain-length carboxylic acids, related to the antiepileptic drug valproic acid (VPA), to the whole rat embryo in vitro was investigated. The protein binding of the drugs in the culture medium determined the placental transfer in vitro: at comparable total concentrations, the substances that bound to a lesser degree (VPA and its metabolite 2-propyl-4-pentenoic acid; 4-en-VPA) reached higher embryonic levels than the more highly bound substances, octanoic acid (OA), 2-methyl-2-ethylcaproic acid (MEC), and the VPA metabolite, 2-propyl-2-pentenoic acid (2-en-VPA). Consequently, the amount of drug added to the culture did not correlate with the transfer to the embryo, but the concentration of the free drug in the culture medium correlated highly with embryonic exposure. The concentration of the drugs in the cultured embryos, the embryonic membranes and the subembryonic fluid were higher than the corresponding free concentrations in the medium. The difference in the teratogenic potency of the substances tested was clearly related to their intrinsic activity, since even high embryonic concentrations of 2-en-VPA, MEC and OA did not produce adverse effects in contrast to VPA and 4-en-VPA which were effective at levels several-fold lower. The effective concentrations of VPA in the cultured embryos were almost ten times lower than those in embryos in vivo. The factors responsible for the high vulnerability of the cultured embryos to the action of VPA are as yet unknown. Our results indicate that the determination of drug concentrations in cultured embryonic tissue is imperative for a rational interpretation of experimental data obtained from in vitro studies; a full validation of in vitro systems must incorporate pharmacokinetic studies.

Potency of monomethyl-, dimethylformamide and some of their metabolites to induce abnormal development in a limb Bud organ culture.

DMF, NMF and their major metabolites were investigated for their developmental toxicity in the mouse limb bud assay. We found that neither DMF, NMF nor the predominant urinary metabolite HMFF exhibited developmental activity. In contrast, all metabolites resulting from the glutathione binding pathway, SMG, SMC and AMCC showed potent developmental activity. Under the chosen exposure conditions, the developmental toxicity of DMF in different species appears to be related to the magnitude of glutathione binding. The results further show the value of using an in vitro system which is incapable of metabolic transformation of exogenous compounds for the identification of ultimate teratogenic species.

Bovine serum: An alternative to rat serum as a culture medium for the rat whole embryo culture.

The results reported here demonstrate the ability of supplemented bovine serum to serve as a culture medium for rat whole embryos. After 48 hours' culture in bovine serum supplemented with Tyrode's buffer and methionine, 9.5-day-old rat embryos were at a stage of development comparable with that of embryos cultivated in homologous serum, although some deficiency in the formation of haemoglobin in embryonic blood cells could be observed. However, supplementation of the culture medium with haemoglobin overcame this deficiency. The procedure used for preparing the culture medium is described in detail and some advantages of bovine serum are discussed.