First- and second-line anti-tuberculosis drug resistance in Northwest Ethiopia

SETTING

Gondar Hospital, Gondar Health Centre, Metemma Hospital, Bahir Dar Hospital and Debre Markos Hospital in Northwest Ethiopia.

OBJECTIVE

To assess the level of and risk factors for first- and second-line drug resistance among tuberculosis (TB) patients.

DESIGN

Drug susceptibility testing (DST) against first-line drugs, including isoniazid (INH), rifampicin (RMP), streptomycin (SM), ethambutol (EMB) and pyrazinamide (PZA), was performed using the BacT/ALERT 3D system. DST against second-line drugs, including fluoroquinolones and aminoglycocides/cyclic peptides, was performed using GenoType MTBDRsl.

RESULTS

Of 260 Mycobacterium tuberculosis isolates, 41 (15.8%) were resistant to at least one first-line drug, 13 (5.0%) were multidrug-resistant (MDR) and 9 (3.5%) were resistant to all first-line drugs. Any resistance to INH, RMP, SM, EMB and PZA was respectively 36 (13.8%), 15 (5.8%), 26 (10.0%), 19 (7.3%) and 12 (4.6%). Of 214 new and 46 previously treated cases, respectively 8 (3.7%) and 5 (10.9%) were MDR. All isolates were susceptible to all second-line drugs.

CONCLUSION

A substantial number of new and previously treated cases harbour MDR-TB. We recommend DST at least for previously treated cases, patients who remain smear-positive at the end of the second month of treatment and patients in close contact with MDR-TB cases. Improved infection control measures need to be implemented in Ethiopia.

On the origin of129I in rain water near Zürich

129I concentrations in precipitation at Dübendorf/Zürich, Switzerland, have been determined with monthly resolution for almost three years in the mid 1990s. The results confirm that annual mean129I concentrations in precipitation in central Europe have remained about constant since the late 1980s. Liquid and gaseous emissions from the nuclear fuel reprocessing plants at Sellafield and La Hague are discussed as the only possible sources of129I in precipitation in central Europe. Based on an upper limit estimate for iodine transferred from the sea to the atmosphere, the gaseous discharges constitute the potentially bigger129I reservoir for precipitation. Moreover, the time dependence of the annual gaseous129I releases from Sellafield and La Hague correlates much better with the129I concentrations in precipitation in central Europe since the late 1980s than does the time dependence of the liquid emissions from these sites. At monthly resolution, the129I concentrations in the precipitation samples close to Zürich exhibit a large variability. A meteorological transport analysis was carried out for four selected months with particularly low or high observed129I concentrations. It was found that meteorological transport alone, based upon assimilated wind fields and observed precipitation values, can not directly account for the large month-to-month variability.

Prospective reliability of the STRokE DOC wireless/site independent telemedicine system

The authors evaluated a site-independent telemedicine system. Telemedicine may be limited by the need for fixed connectivity. Wireless and site-independent technologies eliminate this limitation. Twenty-five stroke patients underwent evaluations by remote and bedside examiners. Ten of 15 (67%) NIH Stroke Scale and 9 of 11 (82%) Modified NIH Stroke Scale items showed excellent interrater reliability. Spearman correlations were > or =0.93. This Internet system is reliable and valid. Further studies should assess its use in acute stroke.

Unusual activity of the Sun during recent decades compared to the previous 11,000 years

Direct observations of sunspot numbers are available for the past four centuries, but longer time series are required, for example, for the identification of a possible solar influence on climate and for testing models of the solar dynamo. Here we report a reconstruction of the sunspot number covering the past 11,400 years, based on dendrochronologically dated radiocarbon concentrations. We combine physics-based models for each of the processes connecting the radiocarbon concentration with sunspot number. According to our reconstruction, the level of solar activity during the past 70 years is exceptional, and the previous period of equally high activity occurred more than 8,000 years ago. We find that during the past 11,400 years the Sun spent only of the order of 10% of the time at a similarly high level of magnetic activity and almost all of the earlier high-activity periods were shorter than the present episode. Although the rarity of the current episode of high average sunspot numbers may indicate that the Sun has contributed to the unusual climate change during the twentieth century, we point out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades.

Persistent solar influence on North Atlantic climate during the Holocene

Surface winds and surface ocean hydrography in the subpolar North Atlantic appear to have been influenced by variations in solar output through the entire Holocene. The evidence comes from a close correlation between inferred changes in production rates of the cosmogenic nuclides carbon-14 and beryllium-10 and centennial to millennial time scale changes in proxies of drift ice measured in deep-sea sediment cores. A solar forcing mechanism therefore may underlie at least the Holocene segment of the North Atlantic's "1500-year" cycle. The surface hydrographic changes may have affected production of North Atlantic Deep Water, potentially providing an additional mechanism for amplifying the solar signals and transmitting them globally.

The relationship between interview characteristics and accuracy of recall in young children: do individual differences matter?

The relationship between interview characteristics and accuracy of recall in young children, as mediated by child characteristics, was examined. The interview characteristics included preinterview instructions and level of questioning. Fifty-six children ranging from ages 3 to 6 years participated in a Circus Day event and were interviewed 10 days later. Following either instructions or filler questions, children were questioned about the event. Results indicated that based on several individual difference factors, young children varied significantly in the accuracy of their interviews and their ability to resist misleading questions. However, individual differences did not mediate children's ability to benefit from different question types or preinterview instructions. As a whole, children provided limited information to the most open-ended questions and more correct information to highly structured questions. In contrast to the research with older children, younger children did not benefit from preinterview instructions. Suggestions for future research and implications for investigative interviews in the field of child abuse are discussed.

Changes in deep-water formation during the Younger Dryas event inferred from 10Be and 14C records

Variations in atmospheric radiocarbon (14C) concentrations can be attributed either to changes in the carbon cycle--through the rate of radiocarbon removal from the atmosphere--or to variations in the production rate of 14C due to changes in solar activity or the Earth's magnetic field. The production rates of 10Be and 14C vary in the same way, but whereas atmospheric radiocarbon concentrations are additionally affected by the carbon cycle, 10Be concentrations reflect production rates more directly. A record of the 10Be production-rate variations can therefore be used to separate the two influences--production rates and the carbon cycle--on radiocarbon concentrations. Here we present such an analysis of the large fluctuations in atmospheric 14C concentrations, of unclear origin, that occurred during the Younger Dryas cold period. We use the 10Be record from the GISP2 ice core to model past production rates of radionuclides, and find that the largest part of the fluctuations in atmospheric radiocarbon concentrations can be attributed to variations in production rate. The residual difference between measured 14C concentrations and those modelled using the 10Be record can be explained with an additional change in the carbon cycle, most probably in the amount of deep-water formation.

Comparison of Mycobacterium tuberculosis susceptibility testing performed with BACTEC 460TB (Becton Dickinson) and MB/BacT (Organon Teknika) systems

The recently introduced automated culture systems MB/BacT (Organon Teknika, Belgium) was compared with radiometric BACTEC 460TB (Becton Dickinson, USA) to test antimicrobial susceptibility of Mycobacterium tuberculosis to first line drugs. On 113 strains 97.5% agreement was obtained, with the difference being not significant. Concordance was practically complete for the most important drugs, isoniazid and rifampin. The two methods however significantly differed for the time needed to complete the test; in fact MB/BacT required on the average five days more than BACTEC 460TB. Despite the delay in the completion of the test, the excellent reliability along with the elimination of radioactivity and full automation make MB/BacT an attractive alternative for susceptibility testing of M. tuberculosis.

Functional imaging of brain areas involved in the processing of coherent and incoherent wide field-of-view visual motion

The brain areas involved in processing wide field-of-view (FOV) coherent and incoherent visual stimuli were studied using positron emission tomography (PET). The brains of nine subjects were scanned as they viewed texture patterns moving in the roll plane. Five visual conditions were used: (1) coherent clockwise (CW) wide-FOV (>100 degrees) roll motion; (2) coherent counter-clockwise (CCW) wide-FOV roll motion; (3) wide-FOV incoherent motion; (4) CCW motion confined to the central visual field (approximately 55 degrees); and (5) a stationary control texture. The region most activated by the coherent-motion stimulus relative to the static one was the medial-occipital cortex, whereas both the medial- and lateral-occipital cortices were activated by incoherent motion relative to a static texture. Portions of the retroinsular parietal-temporal cortex, superior insula, putamen, and vestibulocerebellum responded specifically to the coherence of the stimulus, whereas a widespread lateralized activation was observed upon subtracting the CW scans from the CCW scans. The results indicate separate neural regions for processing wide-FOV motion versus stimulus coherence.

Child characteristics which impact accuracy of recall and suggestibility in preschoolers: is age the best predictor?

OBJECTIVE

The purpose of the present study was to determine whether individual difference factors of metamemory, intelligence, and temperament can improve the ability to predict accuracy of recall and suggestibility in preschoolers.

METHOD

Fifty-six children ranging in age from 43 months to 83 months (M = 61, SD = 9) were recruited from 13 child care centers in a rural southeastern town. Children participated in a "Circus Day" event conducted by two female undergraduate psychology students dressed as clowns. Approximately 10 days (M = 10; SD = 2) after the event, children were interviewed regarding their experiences.

RESULTS AND CONCLUSIONS

Bivariate correlations and multiple regression analyses were performed in order to determine which factors were related and unique contributors to accuracy of recall and suggestibility. Of principal importance is the finding that child characteristics such as metamemory ability, intellectual functioning, and temperament may indeed be helpful in determining a child's capacity to accurately recall information in an interview, although for the most part age is the best predictor. Findings also underscore the importance of considering a child's SES and race when planning and conducting interviews with young children. Possible explanations for these findings as well as implications for future research and clinical application are discussed.

Is "ambient vision" distributed in the brain? Effects of wide-field-view visual yaw motion on PET activation

Ambient vision comprises the visual functions that are associated with the maintenance of spatial orientation and that depend on peripheral, preconscious visual inputs. Although a limited number of brain areas appear to be activated by coherent wide-field-of-view (WFOV) motion in more than one axis, a diffuse pattern of lateralized brain activity occurs in response to clockwise or counterclockwise ambient visual roll motion. In the present study involving positron emission tomography (PET), a similar finding was shown for rightward versus leftward yaw stimulation. A total of 18 PET scans were obtained from six subjects in response to either leftward or rightward WFOV motion in a collimated display subtending > 100 degrees horizontally. Rightward stimulation elicited mainly activation throughout the right hemisphere, whereas leftward stimulation elicited mainly activation throughout the left hemisphere. These findings provide further evidence that the ambient vision signal is either processed or transmitted throughout the entire brain, as befits a visual function that is fundamental to all other perceptual systems.

Expression of c-jun, junB, c-fos, fra-1 and fra-2 mRNA in the rat brain following seizure activity and axotomy

The present study has investigated the congruence of mRNA induction and protein expression of inducible transcription factors (ITFs). The patterns of c-jun, junB, c-fos, fra-1 and fra-2 mRNAs were studied by radioactive and non-radioactive in situ hybridization in the adult rat brain following kainate-induced seizure activity and axotomy. In the same animals, the expression of c-Jun, JunB and c-Fos proteins was compared with the respective mRNA signals. Using radioactive labeled probes all investigated mRNAs showed an onset within 1 h after systemic kainate application and the maximal levels were generally reached after 3 h. Each mRNA displayed a specific temporo-spatial expression pattern. Whereas fra-1 and fra-2 were restricted to the hippocampus, c-jun, junB and c-fos were additionally induced in the cortex, amygdala and thalamus. The areas with maximal labeling were the dentate gyrus and the hippocampal CA1 and CA3 subfields. The expression patterns between c-jun, junB and c-fos mRNA were virtually congruent with the respective protein. Labeling of the junB and fra-2 probes with digoxigenin yielded similar results. Twenty-four hours, 3 and 10 days following transection of the medial forebrain bundle and the mamillo-thalamic tract, high levels of c-jun mRNA (either digoxigenin or radioactive labeled probes) and protein were seen in the axotomized neurons of the substantia nigra pars compacta and mamillary body whereas the other mRNAs studied and the JunB or c-Fos proteins could not be detected. These findings demonstrate that mRNAs encoding for ITFs are translated into the respective proteins following excitotoxic seizures and axotomy, and that the antisera used for immunocytochemistry yield specific expression patterns of homologous proteins.