[Telemedicine in stroke-pertinent to stroke care in Germany]. / Telemedizin in der Schlaganfallversorgung ­ versorgungsrelevant für Deutschland.

BACKGROUND AND OBJECTIVE: Telemedical stroke networks improve stroke care and provide access to time-dependent acute stroke treatment in predominantly rural regions. The aim is a presentation of data on its utility and regional distribution. METHODS: The working group on telemedical stroke care of the German Stroke Society performed a survey study among all telestroke networks. RESULTS: Currently, 22 telemedical stroke networks including 43 centers (per network: median 1.5, interquartile range, IQR, 1-3) as well as 225 cooperating hospitals (per network: median 9, IQR 4-17) operate in Germany and contribute to acute stroke care delivery to 48 million people. In 2018, 38,211 teleconsultations (per network: median 1340, IQR 319-2758) were performed. The thrombolysis rate was 14.1% (95% confidence interval 13.6-14.7%) and transfer for thrombectomy was initiated in 7.9% (95% confidence interval 7.5-8.4%) of ischemic stroke patients. Financial reimbursement differs regionally with compensation for telemedical stroke care in only three federal states. CONCLUSION: Telemedical stroke care is utilized in about 1 out of 10 stroke patients in Germany. Telemedical stroke networks achieve similar rates of thrombolysis and transfer for thrombectomy compared with neurological stroke units and contribute to stroke care in rural regions. Standardization of network structures, financial assurance and uniform quality measurements may further strengthen the importance of telestroke networks in the future.

Acetone formation in the Vibrio family: a new pathway for bacterial leucine catabolism.

There is current interest in biological sources of acetone, a volatile organic compound that impacts atmospheric chemistry. Here, we determined that leucine-dependent acetone formation is widespread in the Vibrionaceae. Sixteen Vibrio isolates, two Listonella species, and two Photobacterium angustum isolates produced acetone in the presence of L-leucine. Shewanella isolates produced much less acetone. Growth of Vibrio splendidus and P. angustum in a fermentor with controlled aeration revealed that acetone was produced after a lag in late logarithmic or stationary phase of growth, depending on the medium, and was not derived from acetoacetate by nonenzymatic decarboxylation in the medium. L-Leucine, but not D-leucine, was converted to acetone with a stoichiometry of approximately 0.61 mol of acetone per mol of L-leucine. Testing various potential leucine catabolites as precursors of acetone showed that only alpha-ketoisocaproate was efficiently converted by whole cells to acetone. Acetone production was blocked by a nitrogen atmosphere but not by electron transport inhibitors, suggesting that an oxygen-dependent reaction is required for leucine catabolism. Metabolic labeling with deuterated (isopropyl-d(7))-L-leucine revealed that the isopropyl carbons give rise to acetone with full retention of deuterium in each methyl group. These results suggest the operation of a new catabolic pathway for leucine in vibrios that is distinct from the 3-hydroxy-3-methylglutaryl-coenzyme A pathway seen in pseudomonads.

A continuous fluorometric assay for pectin methylesterase.

A continuous, fluorometric assay for pectin methylesterase (PME) activity is described. In this assay, methanol produced by PME hydrolysis of pectin methyl esters is oxidized to formaldehyde by alcohol oxidase, and the formaldehyde is continuously reacted with 4-amino-3-penten-2-one to create a stable, fluorescent product. The increase in fluorescence intensity is linearly proportional to PME activity. The assay can be used in crude plant or fungal extracts with relatively little interference with chemicals or buffers commonly used in PME purification. The fluorescence assay has a useful pH range, from pH 5.0 to 6.5, which overlaps pH optima for many bacterial and fungal PMEs, but which limits its usefulness in assaying plant PMEs with alkaline pH optima. Nevertheless, the method is valuable for rapid assay of plant PMEs during their purification or for comparison of plant tissue PME activities.

Methanol Emission from Leaves (Enzymatic Detection of Gas-Phase Methanol and Relation of Methanol Fluxes to Stomatal Conductance and Leaf Development).

We recently reported the detection of methanol emissions from leaves (R. MacDonald, R. Fall [1993] Atmos Environ 27A: 1709-1713). This could represent a substantial flux of methanol to the atmosphere. Leaf methanol production and emission have not been investigated in detail, in part because of difficulties in sampling and analyzing methanol. In this study we used an enzymatic method to convert methanol to a fluorescent product and verified that leaves from several species emit methanol. Methanol was emitted almost exclusively from the abaxial surfaces of hypostomatous leaves but from both surfaces of amphistomatous leaves, suggesting that methanol exits leaves via stomates. The role of stomatal conductance was verified in experiments in which stomates were induced to close, resulting in reduced methanol. Free methanol was detected in bean leaf extracts, ranging from 26.8 [mu]g g-1 fresh weight in young leaves to 10.0 [mu]g g-1 fresh weight in older leaves. Methanol emission was related to leaf development, generally declining with increasing leaf age after leaf expansion; this is consistent with volatilization from a cellular pool that declines in older leaves. It is possible that leaf emission could be a major source of methanol found in the atmosphere of forests.

Marine Vibrio species produce the volatile organic compound acetone.

While screening aerobic, heterotrophic marine bacteria for production of volatile organic compounds, we found that a group of isolates produced substantial amounts of acetone. Acetone production was confirmed by gas chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography. The major acetone producers were identified as nonclinical Vibrio species. Acetone production was maximal in the stationary phase of growth and was stimulated by addition of l-leucine but not the other common amino acids, suggesting that leucine degradation leads to acetone formation. Acetone production by marine vibrios may contribute to the dissolved organic carbon associated with phytoplankton, and some of the acetone produced may be volatilized to the atmosphere.

Sonographic accuracy in the diagnosis of ovarian masses.

Prediction of the tissue diagnosis of ovarian masses has remained a challenge for the sonographer since many adnexal masses have nonspecific sonographic appearances. We evaluated the accuracy of the sonographic diagnosis of adnexal masses in 100 women undergoing laparotomy for ovarian masses within eight weeks of an ultrasound study. Comparison of the preoperative sonographic and final pathologic diagnoses revealed a correct sonographic diagnosis in 68% of the cases. In addition, sonography correctly identified a benign condition in 17% of the cases, though without arriving at the exact tissue diagnosis. Sonography was frankly misleading in 15% of the cases, misreading whether the lesions were benign or malignant. The identification of ovarian malignancy was correct in 24/30 patients (sensitivity, 80%), and the specificity for correctly diagnosing a benign condition was 87%. The positive predictive value of a sonographic diagnosis of an adnexal malignancy was 73%. The negative predictive value of sonography for excluding a malignancy was 91%.

Comparison of serum CA 125, clinical impression, and ultrasound in the preoperative evaluation of ovarian masses.

The ability to differentiate a malignant from a benign ovarian mass was assessed for four diagnostic procedures: serum CA 125, clinical examination, original ultrasound, and reviewer ultrasound interpretation. When these tests were used individually, the sensitivity and specificity of CA 125 levels were equal to those of a review ultrasound. Overall, the sensitivity of clinical impression and original ultrasound was poor. Sensitivity and specificity were highest for CA 125 assays in postmenopausal patients, especially when these were used as the second diagnostic test. Positive and negative predictive values significantly increased among postmenopausal patients when CA 125 was added to any of the other diagnostic tests examined. In conjunction with such tests, measurement of serum CA 125 significantly increased diagnostic accuracy and may thus have an important role in the preoperative evaluation of women with ovarian masses.

Ovarian cancer and talc: a case-control study.

Opportunities for genital exposure to talc were assessed in 215 white females with epithelial ovarian cancers and in 215 control women from the general population matched by age, race, and residence. Ninety-two (42.8%) cases regularly used talc either as a dusting powder on the perineum or on sanitary napkins compared with 61 (28.4%) controls. Adjusted for parity and menopausal status, this difference yielded a relative risk of 1.92 (P less than 0.003) for ovarian cancer associated with these practices. Women who had regularly engaged in both practices had an adjusted relative risk of 3.28 (P less than 0.001) compared to women with neither exposure. This provides some support for an association between talc and ovarian cancer hypothesized because of the similarity of ovarian cancer to mesotheliomas and the chemical relation of talc to asbestos, a known cause of mesotheliomas. The authors also investigated opportunities for potential talc exposure from rubber products such as condoms or diaphragms or from pelvic surgery. No significant differences were noted between cases and controls in these exposures, although the intensity of talc exposure from these sources was likely affected by variables not assessed in this study.