Ythdf2 regulates cardiac remodeling through its mRNA target transcripts.

m6A mRNA methylation controls cardiomyocyte function and increased overall m6A levels are a stereotyping finding in heart failure independent of the underlying etiology. However, it is largely unknown how the information is read by m6A reader proteins in heart failure. Here we show that the m6A reader protein Ythdf2 controls cardiac function and identified a novel mechanism how reader proteins control gene expression and cardiac function. Deletion of Ythdf2 in cardiomyocytes in vivo leads to mild cardiac hypertrophy, reduced heart function, and increased fibrosis during pressure overload as well as during aging. Similarly, in vitro the knockdown of Ythdf2 results in cardiomyocyte growth and remodeling. Mechanistically, we identified the eucaryotic elongation factor 2 as post-transcriptionally regulated by Ythdf2 using cell type specific Ribo-seq data. Our study expands our understanding on the regulatory functions of m6A methylation in cardiomyocytes and how cardiac function is controlled by the m6A reader protein Ythdf2.

Effect of dust exposure and nitrogen oxides on lung function parameters of German coalminers: a longitudinal study applying GEE regression 1974-1998.

PURPOSE: Workplace limits for dust and nitrogen oxides are under review in Germany and the EU. We conducted a study on German coal miners to determine the effects of exposure on lung function. METHODS: Longitudinal inception cohort study (1974-1998) on miners who began working underground at two coal mines between 1974 and 1979. We determined the number of shifts worked underground, the exposure to coal mine dust, quartz dust, nitrogen oxides (NO, NO(2)), smoking behavior, and three lung function parameters (FVC, FEV(1), FEV(1)/FVC). General estimation equation (GEE) models were fitted. RESULTS: 1,369 miners worked an average 3,017 shifts (S) underground. The mean respirable coal mine dust concentration was 1.89 mg/m(3) (quartz: 0.067 mg/m(3)), and the nitrogen oxide concentrations were 0.58 ppm (NO) and 0.007 ppm (NO(2)). On average, 9 measurements of lung function were available per miner. Compared to reference values, the findings were unexceptionable (103, 101, and 99%) on average. GEE-regression models did not reveal detrimental dust exposure effects. Nitrogen oxides (NO (x) = NO + NO(2)) showed small but clearly insignificant effects on lung function: delta FVC = -0.0008 ml/(220 ppmS), P = 0.86, delta FEV(1) = -0.003 ml/(220 ppmS), P = 0.50 and delta FEV(1)%FVC = -0.07%/(220 ppmS), P = 0.22. CONCLUSIONS: The effect of dust exposure on lung function described in older British and American coal miner studies was not confirmed. This can be explained partly by differences in methods (here: longitudinal studies, no prior exposure), but also by lower dust levels. NO (x) exposures showed no relevant influence on lung function-a result confirming findings from British coal mining.

Effects of antidepressant treatment on gene expression profile in mouse brain: cell type-specific transcription profiling using laser microdissection and microarray analysis.

A gene expression study of mice treated with the tricyclic antidepressant amitriptyline was performed. To enable the detection of cell type-specific expression changes, laser-microdissected nucleus accumbens was analysed after 4 and 28 days of treatment. After 4 days of treatment no significantly regulated genes could be detected in this study. In contrast, 95 genes exhibited different expression levels in animals treated for 28 days with amitrityline compared with sham animals. This observation reflects the long-term effects and adaptation processes observed in patients treated with this drug. Among the regulated genes are receptors belonging to the dopamine-dependent signalling cascade, ion channels (mainly voltage-dependent potassium and calcium channels) potentially involved in signalling cascades and neuropeptides. The results support the hypothesis that the therapeutic effect of this antidepressant is much more complex and not confined to a reuptake inhibition of neurotransmitters. Paradigms inducing only weak expression changes, which may be limited to certain cell types within the highly complex brain structure, can therefore be reliably investigated by applying a cell type-specific expression profiling technique based on laser microdissection and subsequent RNA amplification followed by DNA microarray analysis.

In vitro chemosensitivity of paclitaxel and other chemotherapeutic agents in malignant gestational trophoblastic neoplasms.

This is the first report on the ATP cell viability assay as a chemosensitivity test system for gestational trophoblastic neoplasms (GTN). We obtained chemosensitivity profiles in two established trophoblastic cell lines and four fresh tumors. Ten drugs were tested in vitro in the two cell lines JAR and JEG-3. The IC50 values of the 10 chemotherapeutic agents tested were very similar for both cell lines. The three most active drugs in these cell lines were VP-16, paclitaxel and vincristine. This is the first report on the activity of paclitaxel in trophoblastic cell lines. We furthermore evaluated this assay for chemosensitivity testing in four fresh malignant GTN tumors: one placental site trophoblastic tumor, one chorocarcinoma and two invasive moles. The placental site trophoblastic tumor specimen revealed to be rather chemoresistant in vitro whereas the other three tumors were chemosensitive. From our cell line data we conclude that the ATP cell viability assay is a practicable assay for chemosensitivity testing of GTN cell lines and gives repeatable results. However, the value of this assay for fresh GTN chemosensitivity testing needs to be defined.

Assessment of effect of photosensitizers on cytotoxicity of photodynamic therapy in human breast cancer cell cultures.

BACKGROUND: Photodynamic therapy (PDT) might be of clinical value for patients with breast cancer with local recurrences or metastasis. However, there is a need for improved photosensitizers that are effective in combination with laser light and have few, if any, side-effects. We evaluated in vitro the effectiveness of a second generation photosensitizer by testing the influence of laser light on cell cultures of a human breast carcinoma cell line, incubated with meta-tetrahydroxyphenylchlorin (m-THPC) (= Temoporfin). EXPERIMENTAL DESIGN: Five thousand MCF-7 cells were plated in 96-well plates. Forty-eight hours before laser treatment, the cells were plated to achieve a monolayer configuration. Twenty-four hours after plating, they were incubated with m-THPC. On day 6 after treatment with m-THPC we lysed the cells to extract the intracellular ATP that correlates with the number of living cells. The ATP-CVA was used to assess the cytotoxicity of the tested photosensitizer m-THPC at various concentrations and the relevant laser light alone prior to their combination after six days of culture. RESULTS: We found a dose-response for m-THPC alone ranging from 2 to 16 micrograms/ml. The calculated inhibition concentration to produce 50% cell kill (IC50) was 4.55 micrograms/ml. We also observed a very low cytotoxicity for laser irradiation alone but a very strong cell kill for the combination of m-THPC together with laser light. CONCLUSIONS: PDT gave almost total cell kill at m-THPC concentrations that are not toxic in vitro.

Nerve conduction studies: orthodromic vs antidromic latencies.

Variables known to affect the sensory nerve action potential (SNAP) include the method of measuring the SNAP, electrode placement and local impedance, volume conduction, temperature, age, nerve fiber composition, and duration dependent phase cancellation. There is debate, however, concerning the effect of orthodromic vs antidromic stimulation on the latency of the SNAP. This question was studied with the same methodology of those who reported a difference between antidromic and orthodromic latencies, but with control of the interelectrode distance. Twenty-five normal hands were studied. The median and ulnar digital nerves were analyzed both orthodromically and antidromically. There was careful control of interelectrode distance, which was the same for both the recording and stimulating electrodes. Studies were done with both a 3-cm and 4-cm interelectrode distance. Parameters recorded were onset latency, peak latency, terminal latency, and amplitude (baseline to negative peak, and peak to peak). Extensive statistical analysis was performed for all parameters. No differences were found between antidromic and orthodromic studies when the interelectrode distance was the same.

Phase I study of 24-hour continuous intravenous infusion of recombinant human tumor necrosis factor.

Sixteen patients with cancer were treated with a 24-h continuous intravenous infusion of recombinant human tumor necrosis factor (rHuTNF) to investigate the spectrum of side-effects, the maximum tolerated dose, the pharmacokinetics, and possible antitumor effects. Fever, chills, and flu-like symptoms were the most common side-effects. The maximum tolerated dose was 6 x 10(5) U/m2 (261 micrograms/m2). Severe hypotension, fluid retention, watery diarrhea, and central nervous deficits culminated in a profound prostration as the dose-limiting toxicity. No allergic reactions, positive skin tests, or antibodies against rHuTNF were observed. Plasma levels of rHuTNF were detected at doses of greater than or equal to 3 x 10(5) U/ml2. Maximal plasma levels were 19 U/ml (8.2 ng/ml). No objective tumor responses were observed.

Meningitis-related hearing loss evaluated with evoked potentials.

Sixty-seven children with meningitis, ranging in age from 1 month to 14 years, were studied using brainstem auditory evoked potentials. Abnormal results were present in 60% of the subjects. Serial studies were obtained in 30% of the abnormal patients, 75% of whom demonstrated continued abnormalities on subsequent examination. Abnormal studies were found only in those patients who were 6 years of age or younger. The most prominent finding was an increased interwave interval resulting from increased wave V latencies. Additional abnormalities included an increased slope of the latency-intensity function suggestive of sensory-neural hearing loss. These studies clearly indicate the significance of early detection by the use of evoked potentials in the early diagnosis of hearing disorders in children with meningitis.

Infantile spasms associated with hemihypsarrhythmia and hemimegalencephaly.

A case of unilateral megalencephaly in a four-week-old child with infantile spasms and hemihypsarrhythmia is presented. The histological and histometrical investigations showed signs of immaturity in the cortex of the megalencephalic hemisphere.

A human embryo of 28 mm crown-rump length with cerebral, esophagotracheal and cardiovascular malformations.

The following malformations were observed in a human embryo of 28 mm crown-rump length obtained at operation for tubal rupture in a case of extrauterine pregnancy: 1. Secondary anophthalmia with dysplasia and in part aplasia of the diencephalon. Rudiments of both eyes and eyestalklike proliferations within the diencephalon. No lenses and on the left side only a palpebral fissure. Hypoplasia of the right telencephalic hemisphere and of the right side of diencephalon, mesencephalon and proximal parts of the medulla oblongata. Pseudotumorous proliferations in the diencephalon, in the alar plate of the medulla oblongata (protruding into the fourth ventricle) and in the arachnoid. Hypoplasia of the right internal, middle, and external ear. Dysplasia and in part aplasia of facial osseous elements (cebocephalia). 2. Proximal esophageal atresia with distal tracheoesophageal fistula. 3. A Fallot's tetralogy with right-sided aortic arch and regressive right-sided ductus arteriosus, tricuspid atresia, hypoplasia of the right ventricle with excessive hypertrophy of its wall, and hypoplasia of the pulmonary trunk. Single left superior vena cava and abnormal, semicircular course of the stems of both coronary arteries.