OUP accepted manuscript

Background

Malaria in pregnancy remains a significant cause of morbidity and mortality, affecting the highly endemic countries of sub-Saharan Africa (SSA). Insecticide-treated nets (ITNs) are effective for malaria prevention. However, poor adherence in SSA remains a challenge.

Methods

We conducted a standard questionnaire survey among 710 pregnant women from 37 primary care clinics in the Upper West Region of Ghana from January through May 2019. Using a sequential explanatory design, we integrated the survey data from six focus group discussions with pregnant women.

Results

While 67% of women had some general knowledge about malaria prevention, only 19% knew the specific risks in pregnancy. Determinants of ITN use included ITN ownership (odds ratio [OR] 2.4 [95% confidence interval {CI} 1.3 to 4.4]), good maternal knowledge of the risks of malaria in pregnancy (OR 2.4 [95% CI 1.3 to 4.3]) and more antenatal care (ANC) contacts (OR 1.3 [95% CI 1.0 to 1.5)]. Focus group discussions showed that non-use of ITNs resulted from inappropriate hanging infrastructure, a preference for other malaria prevention alternatives, allergy and heat.

Conclusions

Specific maternal knowledge of malaria risks in pregnancy was low and influenced the regular use of ITNs. Community and ANC-based malaria interventions should prioritize increasing knowledge of the specific risks of malaria.

[Interdisciplinary neurovascular networks: state of the art]

BACKGROUND

In order to treat the complete spectrum of neurovascular diseases at a high level of quality, which goes beyond the purely acute treatment of stroke, the German Stroke Society (DSG) together with the German Societies for Neurosurgery and Neuroradiology developed a certification procedure for neurovascular networks (NVN). Structurally, a NVN consists of a coordinating center with at least three neurovascular network partners with a certified stroke unit. From 2018 to 2020 a total of 15 NVN have so far been audited and certified according to this new standard.

OBJECTIVE

How efficient are the NVN? Are high standards maintained?

MATERIAL AND METHODS

The reports of the audits were analyzed. The data were taken from the period 2017-2019.

RESULTS

The 15 NVN treated a total of 86,510 stroke patients in the years examined and were networked with a total of 107 partner clinics, which were situated an average of 25 km from the coordinating center and transferred a total of 2726 patients. The coordinating centers performed 2463 thrombectomies and treated 2383 patients with nontraumatic intracerebral bleeding. In 712 patients with acute aneurysmatic subarachnoid hemorrhages endovascular treatment was carried out and clipping in 401. The audit was successful in the majority of the NVN.

CONCLUSION

The certification process of NVN has been successfully established and the audits proved to be a useful instrument for quality control and improvement. The 15 NVN are highly efficient and treat more than one quarter of stroke patients in German stroke units.

Knowledge of risks of malaria in pregnancy on use of ITNs among pregnant women in northern Ghana

Background

Every year malaria in pregnancy causes 10,000 maternal mortalities worldwide, 20% of stillbirths, 11% of all new-born deaths and 900,000 low-birth-weight babies in sub-Saharan Africa. Maternal knowledge of malaria risks in pregnancy plays a significant role in malaria prevention. However, it is unknown if this preventable loss of lives and morbidities are caused by lack of knowledge, lack of prevention tools or both. We measured the pregnancy-related risks of malaria knowledge and bed net availability and use among pregnant women in Ghana.

Methods

We interviewed 770 pregnant women who attended antenatal care in 37 primary care clinics in Ghana from January through May 2019. We integrated this data in a sequential explanatory design with qualitative insights from 6 focus groups with 8 pregnant women each.

Results

697/770 questionnaires were analyzed. 67% have general knowledge on malaria prevention but only 19% knew the specific risks on pregnancy outcomes. ITNs were owned by 89%, but only 75% reported to regularly use them. There was a statistically significant correlation between specific risks of malaria knowledge and ITN use (P<.001, OR = 2.0, CI:1.3-3.0). Other factors associated with ITN use were higher income, owning an ITN, higher parity, formal education, religion, and age. Reasons for non-adherence to ITN use include inappropriate hanging infrastructure, discomfort with using an ITN, and use of other prevention alternatives.

Conclusions

The study demonstrates that maternal knowledge on the risks of malaria in pregnancy significantly influenced their adherence to the use of insecticide-treated bed nets.

Key messages

The use of ITNs as a prevention method for malaria correlates to the knowledge of mothers about risks of malaria in pregnancy. Antenatal care malaria prevention efforts should focus more on teaching the specific risks of malaria in pregnancy.

Efficacy and safety of methylene blue in the treatment of malaria: a systematic review

BACKGROUND

Methylene blue (MB) was the first synthetic antimalarial to be discovered and was used during the late 19th and early 20th centuries against all types of malaria. MB has been shown to be effective in inhibiting Plasmodium falciparum in culture, in the mouse model and in rhesus monkeys. MB was also shown to have a potent ex vivo activity against drug-resistant isolates of P. falciparum and P. vivax. In preclinical studies, MB acted synergistically with artemisinin derivates and demonstrated a strong effect on gametocyte reduction in P. falciparum. MB has, thus, been considered a potentially useful partner drug for artemisinin-based combination therapy (ACT), particularly when elimination is the final goal. The aim of this study was to review the scientific literature published until early 2017 to summarise existing knowledge on the efficacy and safety of MB in the treatment of malaria.

METHODS

This systematic review followed PRISMA guidelines. Studies reporting on the efficacy and safety of MB were systematically searched for in relevant electronic databases according to a pre-designed search strategy. The search (without language restrictions) was limited to studies of humans published until February 2017.

RESULTS

Out of 474 studies retrieved, a total of 22 articles reporting on 21 studies were eligible for analysis. The 21 included studies that reported data on 1504 malaria patients (2/3 were children). Older studies were case series and reports on MB monotherapy while recent studies were mainly controlled trials of combination regimens. MB was consistently shown to be highly effective in all endemic areas and demonstrated a strong effect on P. falciparum gametocyte reduction and synergy with ACT. MB treatment was associated with mild urogenital and gastrointestinal symptoms as well as blue coloration of urine. In G6PD-deficient African individuals, MB caused a slight but clinically non-significant haemoglobin reduction.

CONCLUSIONS

More studies are needed to define the effects of MB in P. falciparum malaria in areas outside Africa and against P. vivax malaria. Adding MB to ACT could be a valuable approach for the prevention of resistance development and for transmission reduction in control and elimination programs.

SYSTEMATIC REVIEW REGISTRATION

This study is registered at PROSPERO (registration number CRD42017062349 ).

Community perception regarding childhood vaccinations and its implications for effectiveness: a qualitative study in rural Burkina Faso

Background

Vaccination has contributed to major reductions in global morbidity and mortality, but there remain significant coverage gaps. Better knowledge on the interplay between population and health systems regarding provision of vaccination information and regarding health staff organization during the immunization sessions appears to be important for improvements of vaccination effectiveness.

Methods

The study was conducted in the Nouna Health and Demographic Surveillance System (HDSS) area, rural Burkina Faso, from March to April 2014. We employed a combination of in-depth interviews (n = 29) and focus group discussions (n = 4) including children’s mothers, health workers, godmothers, community health workers and traditional healers. A thematic analysis was performed. All material was transcribed, translated and analyzed using the software ATLAS.ti4.2.

Results

There was better social mobilization in the rural areas as compared to the urban area. Most mothers know the Expanded Program of Immunization (EPI) target diseases, and the importance to immunize their children. However, the great majority of informants reported that mothers don’t know the vaccination schedule. There is awareness that some children are incompletely vaccinated. Mentioned reasons for that were migration, mothers being busy with their work, the practice of not opening vaccine vials unless a critical number of children are present, poor interaction between women and health workers during immunization sessions, potential adverse events associated with vaccination, geographic inaccessibility during rainy season, and lack of information.

Conclusions

Well organized vaccination programs are a key factor to improve child health and there is a clear need to consider community perceptions on program performance. In Burkina Faso, a number of factors have been identified which need attention by the EPI managers for further improvement of program effectiveness.

The CHESS score: a simple tool for early prediction of shunt dependency after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Acute hydrocephalus is an early and common complication of aneurysmal subarachnoid hemorrhage (SAH). However, considerably fewer patients develop chronic hydrocephalus requiring shunt placement. Our aim was to develop a risk score for early identification of patients with shunt dependency after SAH.

METHODS

Two hundred and forty-two SAH individuals who were treated in our institution between January 2008 and December 2013 and survived the initial impact were retrospectively analyzed. Clinical parameters within 72 h after the ictus were correlated with shunt dependency. Independent predictors were summarized into a new risk score which was validated in a subsequent SAH cohort treated between January and December 2014.

RESULTS

Seventy-five patients (31%) underwent shunt placement. Of 23 evaluated variables, only the following five showed independent associations with shunt dependency and were subsequently used to establish the Chronic Hydrocephalus Ensuing from SAH Score (CHESS, 0-8 points): Hunt and Hess grade ≥IV (1 point), location of the ruptured aneurysm in the posterior circulation (1 point), acute hydrocephalus (4 points), the presence of intraventricular hemorrhage (1 point) and early cerebral infarction on follow-up computed tomography scan (1 point). The CHESS showed strong correlation with shunt dependency (P = 0.0007) and could be successfully validated in both internal SAH cohorts tested. Patients scoring ≥6 CHESS points had significantly higher risk of shunt dependency (P < 0.0001) than other patients.

CONCLUSION

The CHESS may become a valuable diagnostic tool for early estimation of shunt dependency after SAH. Further evaluation and external validation will be required in prospective studies.

Quick scanning monochromator for millisecond in situ and in operando X-ray absorption spectroscopy

The design and capabilities of a novel Quick scanning Extended X-ray Absorption Fine Structure (QEXAFS) monochromator are presented. The oscillatory movement of the crystal stage is realized by means of a unique open-loop driving scheme operating a direct drive torque motor. The entire drive mechanics are installed inside of a goniometer located on the atmospheric side of the vacuum chamber. This design allows remote adjustment of the oscillation frequency and spectral range, giving complete control of QEXAFS measurements. It also features a real step-scanning mode, which operates without a control loop to prevent induced vibrations. Equipped with Si(111) and Si(311) crystals on a single stage, it facilitates an energy range from 4.0 keV to 43 keV. Extended X-ray absorption fine structure spectra up to k = 14.4 Å(-1) have been acquired within 17 ms and X-ray absorption near edge structure spectra covering more than 200 eV within 10 ms. The achieved data quality is excellent as shown by the presented measurements.

[Diagnosis and treatment of diving accidents. New German guidelines for diving accidents 2014-2017]

In 2015 the German Society for Diving and Hyperbaric Medicine (GTÜM) and the Swiss Underwater and Hyperbaric Medical Society (SUHMS) published the updated guidelines on diving accidents 2014-2017. These multidisciplinary guidelines were developed within a structured consensus process by members of the German Interdisciplinary Association for Intensive Care and Emergency Medicine (DIVI), the Sports Divers Association (VDST), the Naval Medical Institute (SchiffMedInst), the Social Accident Insurance Institution for the Building Trade (BG BAU), the Association of Hyperbaric Treatment Centers (VDD) and the Society of Occupational and Environmental Medicine (DGAUM). This consensus-based guidelines project (development grade S2k) with a representative group of developers was conducted by the Association of Scientific Medical Societies in Germany. It provides information and instructions according to up to date evidence to all divers and other lay persons for first aid recommendations to physician first responders and emergency physicians as well as paramedics and all physicians at therapeutic hyperbaric chambers for the diagnostics and treatment of diving accidents. To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose and the following key action statements: on-site 100% oxygen first aid treatment, still patient positioning and fluid administration are recommended. Hyperbaric oxygen (HBO) recompression remains unchanged the established treatment in severe cases with no therapeutic alternatives. The basic treatment scheme recommended for diving accidents is hyperbaric oxygenation at 280 kPa. For quality management purposes there is a need in the future for a nationwide register of hyperbaric therapy.

Hard disk drive based microsecond X-ray chopper for characterization of ionization chambers and photodiodes

A fast X-ray chopper capable of producing ms long X-ray pulses with a typical rise time of few μs was realized. It is ideally suited to investigate the temporal response of X-ray detectors with response times of the order of μs to ms, in particular, any kind of ionization chambers and large area photo diodes. The drive mechanism consists of a brushless DC motor and driver electronics from a common hard disk drive, keeping the cost at an absolute minimum. Due to its simple construction and small dimensions, this chopper operates at home lab based X-ray tubes and synchrotron radiation sources as well. The dynamics of the most important detectors used in time resolved X-ray absorption spectroscopy, namely, ionization chambers and Passivated Implanted Planar Silicon photodiodes, were investigated in detail. The results emphasize the applicability of this X-ray chopper.

Socio-demographic determinants of timely adherence to BCG, Penta3, measles, and complete vaccination schedule in Burkina Faso

OBJECTIVE

To identify the determinants of timely vaccination among young children in the North-West of Burkina Faso.

METHODS

This study included 1665 children between 12 and 23 months of age from the Nouna Health and Demographic Surveillance System, born between September 2006 and December 2008. The effect of socio-demographic variables on timely adherence to the complete vaccination schedule was studied in multivariable ordinal logistic regression with 3 distinct endpoints: (i) complete timely adherence, (ii) failure, and (iii) missing vaccination. Three secondary endpoints were timely vaccination with BCG, Penta3, and measles, which were studied with standard multivariable logistic regression.

RESULTS

Mothers' education, socio-economic status, season of birth, and area of residence were significantly associated with failure of timely adherence to the complete vaccination schedule. Year of birth, ethnicity, and the number of siblings was significantly related to timely vaccination with Penta3 but not with BCG or measles vaccination. Children living in rural areas were more likely to fail timely vaccination with BCG than urban children (OR=1.79, 95%CI=1.24-2.58 (proximity to health facility), OR=3.02, 95%CI=2.18-4.19 (long distance to health facility)). In contrast, when looking at Penta3 and measles vaccination, children living in rural areas were far less likely to have failed timely vaccinations than urban children. Mother's education positively influenced timely adherence to the vaccination schedule (OR=1.42, 95%CI 1.06-1.89). There was no effect of household size or the age of the mother.

CONCLUSIONS

Additional health facilities and encouragement of women to give birth in these facilities could improve timely vaccination with BCG. Rural children had an advantage over the urban children in timely vaccination, which is probably attributable to outreach vaccination teams amongst other factors. As urban children rely on their mothers' own initiative to get vaccinated, urban mothers should be encouraged more strongly to get their children vaccinated in time.

Compensating motion artifacts of 3D in vivo SD-OCT scans

We propose a probabilistic approach for compensating motion artifacts in 3D in vivo SD-OCT (spectral-domain optical coherence tomography) tomographs. Subject movement causing axial image shifting is a major problem for in vivo imaging. Our technique is applied to analyze the tissue at percutaneous implants recorded with SD-OCT in 3D. The key challenge is to distinguish between motion and the natural 3D spatial structure of the scanned subject. To achieve this, the motion estimation problem is formulated as a conditional random field (CRF). For efficient inference, the CRF is approximated by a Gaussian Markov random field. The method is verified on synthetic datasets and applied on noisy in vivo recordings showing significant reduction of motion artifacts while preserving the tissue geometry.

Direct visualization of cerebellar nuclei in patients with focal cerebellar lesions and its application for lesion-symptom mapping

As yet, human cerebellar lesion studies have not taken advantage of direct magnetic resonance imaging (MRI) of the cerebellar nuclei in individual patients. In the present study, susceptibility weighted imaging (SWI) was used to visualize lesions of the dentate nuclei in patients with chronic focal lesions. Fifteen patients with cerebellar lesions either due to stroke or tumor surgery underwent SWI imaging using a 1.5T MRI scanner. Dentate nuclei were seen as hypointensities in all patients. Three of the patients underwent additional SWI imaging at 3T and 7T. Compared to 1.5T, corrugation of the dentate wall was seen with greater precision and the dorsal, iron-poorer part was seen more fully. Lesion-symptom mapping was performed based on the 1.5T MR images. Patients were divided into two groups with and without upper limb ataxia. A region-of-interest-(ROI)-driven normalization technique was used which had initially been developed by Diedrichsen et al. (2011) for functional MRI (fMRI) of the dentate nuclei. Compared to conventional normalization of the cerebellum, overlap of dentate lesions improved and lead to increased sensitivity of lesion-symptom maps. Subtraction analysis revealed that the more dorsal and rostral parts of the dentate nuclei were related to upper limb ataxia. Findings were in good accordance with the dentate hand area shown in recent fMRI studies. These data provide evidence that direct identification of dentate lesions together with the ROI-driven normalization technique allows for improved lesion-symptom mapping at the level of the cerebellar nuclei already at conventional 1.5T MRI field strength.

[Neurostimulation for treatment of headaches]

Only a small portion of patients with primary headaches are refractory to treatment concerning relief of headache episodes and prophylactic therapy of headaches. New methods of central and peripheral neurostimulation have been developed for these patients during the last few years and experience was mostly gained in small case series. The following overview gives a description of new stimulation methods, such as deep brain stimulation, occipital nerve stimulation, vagal nerve stimulation, neurostimulation of the sphenopalatine ganglion and transcranial magnetic stimulation.

Malnutrition in young children of rural Burkina Faso: comparison of survey data from 1999 with 2009

OBJECTIVE

For measurement of progress towards the Millennium Development Goal (MDG) 1, reliable data on nutrition indicators of specific countries are essential. Malnutrition is also the main determinant for childhood mortality, which is addressed in MDG 4.

METHODS

In the health and demographic surveillance area of Kossi Province in north-western Burkina Faso, nutritional parameters were compared in two cohorts of young children of the same age range from eight villages. Surveys took place in June and December of the year 1999 and 2009. A multivariate model was used to control for confounding variables.

RESULTS

For the 1999 study, data were analysed for 179 and 197 children who took part in the June and December survey respectively. In 2009, corresponding data were analysed for 460 and 409 children. Prevalence of underweight was highest in December 1999 (42.6%) and lowest in December 2009 (34.1%). After adjustment for age, sex and village, there was a slight but not always significant improvement in the z-scores of weight-for-age, weight-for-length, length-for-age, and mid-arm circumference over time.

CONCLUSIONS

The findings from this study confirm the still unacceptable high prevalence of malnutrition in young children of rural sub-Saharan Africa (SSA). Progress in the reduction of malnutrition remains slow on this continent making it rather unlikely that the corresponding MDGs will be achieved. Large-scale multi-sectoral community-based interventions are urgently needed for a sustainable improvement of child health in SSA.

Structural properties of fluorozirconate-based glass ceramics doped with multivalent europium

The structure/property relationships of fluorochlorozirconate glass ceramics as a function of divalent and trivalent europium (Eu) co-doping and thermal processing have been investigated; the influence of doping ratio on the formation of barium chloride (BaCl(2)) nanocrystals therein was elucidated. X-ray absorption near-edge structure spectroscopy shows that the post-thermal annealing changes the Eu valence of the as-poured glass slightly, but during the melting process Eu(3+) is more strongly reduced to Eu(2+), in particular, when doped as a chloride instead of fluoride compound. The Eu(2+)-to-Eu(3+) doping ratio also plays a significant role in chemical equilibrium in the melt. X-ray diffraction measurements indicate that a higher Eu(2+) fraction leads to a BaCl(2) phase transition from hexagonal to orthorhombic structure at a lower temperature.

Effectiveness of a community intervention on malaria in rural Tanzania - a randomised controlled trial

BACKGROUND

Malaria infections are a major public health problem in Africa and prompt treatment is one way of controlling the disease and saving lives.

METHODS

This cluster-randomised controlled community intervention conducted in 2003-2005 aimed at improving early malaria case management in under five children. Health workers were trained to train community-based women groups in recognizing malaria symptoms, providing first-line treatment for uncomplicated malaria and referring severe cases. Evaluation was through a pre- (2004) and a post-intervention survey (2005). Anaemia prevalence was the primary outcome.

RESULTS

1715 children aged 6-59 months were included in the pre-intervention survey and 2169 in the post-intervention survey. The prevalence of anaemia decreased significantly from 37% [95% CI 34.7-39.3] to 0.5% [95% CI 0.2-0.7] after the intervention (p<0.001); slightly more in the intervention (from 43.9% to 0.8%) than in the control (30.8% to 0.17%) group (p=0.038). Fever and reported fever decreased significantly and the mean body weight of the children increased significantly over the study period in both control and intervention groups.

CONCLUSION

The decrease in anaemia was significantly associated with the intervention, whereas the fever and body weight trends might be explained by other malaria control activities or seasonal/climate effects in the area. The community intervention was shown to be feasible in the study context.

[Technological intervention in the self? An ethical evaluation of deep brain stimulation relating to patient narratives]

Technological interventions into the brain raise a number of ethical questions, particularly, questions of personality change and control or manipulation of the human mind. Taking patients undergoing deep brain stimulation as an example, the authors analyse the possible impact of neurotechnologies on human self-perception in individual cases as well as in general. Following the concept of narrative-based medicine and ethics patients' narrations are presented in order to discuss the value of this approach for developing normative considerations as well as for deriving practical consequences regarding the physician-patient-relationship.

[Loading of the tibiotalar joint and Chopart's joint following subtalar arthrodesis: dynamic cadaver study of 5 specimens]

AIM

Little has been known until now about biomechanical intra-articular changes in the condition of adjacent joints following subtalar arthrodeses.

METHOD

We tested 5 cadaver specimens in a dynamic axially loaded foot model under computer-regulated load application on 9 extrinsic tendons of the foot regarding changes in load under native conditions and following an anatomically fixed subtalar arthrodesis.

RESULTS

We saw an averaged native force transmission in the talonavicular joint of 87 N, increasing post-arthrodesis to 92 N. In the calcaneocuboid joint we measured an increase from 72 N to 74 N. For peak pressure, the increase was from native 3152 kPa to 3286 kPa in the talonavicular joint and in the calcaneocuboid joint we recorded a reduction from 3282 kPa to 3277 kPa. The effects are not striking from a statistical viewpoint. However, we observed a reduction in force from native 103 N to 90 N and in peak pressure from 4778 kPa to 4261 kPa in the ankle. When the ankle was divided into discrete zones in the sagittal and frontal planes there was no evidence of load displacement.

CONCLUSION

Our measurements show that anatomically fixed arthrodeses of the talocalcanear joint do not lead to any striking increase in loads on adjacent joints. Any adjacent segment degeneration following subtalar arthrodeses may be the result of changes in joint kinematics or non-anatomically reconstructed hindfoot positions.

Ability of mothers to diagnose fever and anaemia in their young children, in a malaria-endemic region of West Africa

The rapid and correct diagnosis of fever and anaemia at the household level is a prerequisite for the successful management and control of life-threatening disease among young children, particularly in malaria-endemic areas of Africa. The ability of mothers to diagnose fever and anaemia in their young children has recently been explored, as part of a large, birth-cohort study in rural, north-western Burkina Faso. During a cross-sectional survey in six villages, 345 children aged, <3 years and their mothers were investigated. Each mother was asked if she considered her child to be febrile and/or anaemic before that child's temperature and haematocrit were measured, with an electronic thermometer and portable centrifuge, respectively. The recorded prevalences of fever (> or =37.5 degrees C) and anaemia (haematocrit, <25%) in the children were 12.2% and 21.4%, respectively. The mothers' diagnoses had a sensitivity of 76.2% [95% confidence interval (CI)=60.6%-88.0%] for fever and 4.1% (CI=0.8%-11.4%) for anaemia, with corresponding specificities of 87.1% (CI=82.8%-90.7%) and 95.9% (CI=92.9%-98.0%). Mothers in rural Africa appear to be fairly accurate in detecting fever in their children but less accurate in detecting anaemia. While malaria control needs to employ a mix of preventive and curative measures, anaemia control will benefit from community-based malaria-control measures as well as broader approaches addressing the nutritional status of young children.

[Prediction of the location of the centre of rotation of the hip joint external landmarks]

AIM

The object of this study was to develop a new method to predict the location of the centre of rotation of the hip joint reasonably accurately.

METHOD

We collected the coordinates of palpable bony landmarks in 50 patients, 25 males and 25 females, using CT scans to predict the physiological location of the centre of the hip joint centre.

RESULTS

The centre of the hip was located, on average, at 12% (+/- 2.9) of the inter-ASIS (anterior superior iliac spine) distance medial, 33% (+/- 3.9) distal and 19% (+/- 2.7) posterior to the anterior superior iliac spine (ASIS).

CONCLUSION

Knowledge of the physiological centre of rotation of the hip may be useful in navigation of the cup in total hip arthroplasty.

Absolute beta-catenin concentrations in Wnt pathway-stimulated and non-stimulated cells

The intracellular level of the proto-oncoprotein beta-catenin is a parameter for the activity of the Wnt pathway, which has been linked to carcinogenesis. The paper introduces a novel sandwich-based ELISA for the determination of the beta-catenin concentration in lysates from cells or tissues. The advantages of the method were proven by determining beta-catenin levels in cell lines and in cells after activation of the Wnt pathway. Analysis revealed high beta-catenin concentrations in the cell lines HeLa, KB, HT1080, MCF-7, U-87 and U-373, which had not been described before. Beta-catenin concentrations were compared in HEK293 and C57MG cells after activation of the Wnt pathway. The beta-catenin concentrations increased by different factors depending on whether the Wnt pathway was activated by incubation with LiCl or with Wnt-3a-conditioned medium. This finding indicated that the beta-catenin level depends on the way and level of Wnt pathway activation. The quantitative analysis of beta-catenin in colorectal tumours revealed high beta-catenin levels in tumours with truncating mutations in the APC gene.

Mögliche Auswirkungen des Klimawandels auf die Ausbreitung der Malaria Tropica - Ergebnisse einer strategischen Simulation

The Earth's surface is presently undergoing a period of global warming-up, which increases the likelihood of a spread of malaria tropica. A reliable prognosis would be important for efficient prevention by initiating appropriate counter-measures well in time. The following paper presents simulations of the effects of climatic changes on the spread of malaria. We do not specifically aim at obtaining concrete data for a particular region; rather, we are concerned with gaining an insight into the complex interrelations between global environment changes and the spread of malaria.