28 research outputs found
Lateral variability of ichnological content in muddy contourites: Weak bottom currents affecting organismsâ behavior
Although bioturbation is commonly recognized in contourites, only a few studies have analyzed the
ichnological content of these deposits in detail. These studies have mainly focused on meso-scale
bigradational sequence (a coarsening upward followed by a fining-upward sequence resulting from
variations in current velocity). Here we present data from gravitational cores collected along the
NW Iberian Margin showing systematic variation in ichnological content across proximal to distal
depocenters within a large-scale elongated contourite drift. Data demonstrate that tracemakersâ
behavior varies depending on the distance relative to the bottom current core. Trace fossils are
already known to be a useful tool for studying of contouritic deposits and are even used as criterion
for differentiating associated facies (e.g., turbidites, debrites), though not without controversy. We
propose a mechanism by which the distance to the bottom current core exerts tangible influence on
specific macro-benthic tracemaker communities in contourite deposits. This parameter itself reflects
other bottom current features, such as hydrodynamic energy, grain size, nutrient transport, etc.
Ichnological analysis can thus resolve cryptic features of contourite drift depositional settings.The contribution and research by JD was funded through the European Unionâs Horizon 2020 research and
innovation programme under the Marie SkĆodowska-Curie grant agreement No 792314 (ICON-SE). The
research of FJR-T was funded by project CGL2015-66835-P (SecretarĂa de Estado de Investigacion, Desarrollo e
Innovacion, Spain), Research Group RNM-178 (Junta de AndalucĂa), and Scientific Excellence Unit UCE-2016-
05 (Universidad de Granada). AMâs research is funded by the I2C program of the Xunta de Galicia Postdoctoral
programme (ED481B 2016/029-0). The research was conducted as part of âThe Drifters Research Groupâ (RHUL)
and âIchnology and Palaeoenvironment Research Groupâ (UGR) programs
Faecal pharmacokinetics of orally administered vancomycin in patients with suspected Clostridium difficile infection
<p>Abstract</p> <p>Background</p> <p>Oral vancomycin (125 mg qid) is recommended as treatment of severe <it>Clostridium difficile </it>infection (CDI). Higher doses (250 or 500 mg qid) are sometimes recommended for patients with very severe CDI, without supporting clinical evidence. We wished to determine to what extent faecal levels of vancomycin vary according to diarrhoea severity and dosage, and whether it is rational to administer high-dose vancomycin to selected patients.</p> <p>Methods</p> <p>We recruited hospitalized adults suspected to have CDI for whom oral vancomycin (125, 250 or 500 mg qid) had been initiated. Faeces were collected up to 3 times/day and levels were measured with the AxSYM fluorescence polarization immunoassay.</p> <p>Results</p> <p>Fifteen patients (9 with confirmed CDI) were treated with oral vancomycin. Patients with â„4 stools daily presented lower faecal vancomycin levels than those with a lower frequency. Higher doses of oral vancomycin (250 mg or 500 mg qid) led to consistently higher faecal levels (> 2000 mg/L), which were 3 orders of magnitude higher than the MIC<sub>90 </sub>of vancomycin against <it>C. difficile</it>. One patient receiving 125 mg qid had levels below 50 mg/L during the first day of treatment.</p> <p>Conclusions</p> <p>Faecal levels of vancomycin are proportional to the dosage administered and, even in patients with increased stool frequency, much higher than the MIC<sub>90</sub>. Patients given the standard 125 mg qid dosage might have low faecal levels during the first day of treatment. A loading dose of 250 mg or 500 mg qid during the first 24-48 hours followed by the standard dosage should be evaluated in larger studies, since it might be less disruptive to the colonic flora and save unnecessary costs.</p
Induction cisplatinâirinotecan followed by concurrent cisplatinâirinotecan and radiotherapy without surgery in oesophageal cancer: multicenter phase II FFCD trial
A recent phase I study showed that weekly cisplatin, irinotecan and concurrent radiotherapy can be administered with moderate toxicity in patients with oesophageal cancer. Patients with no prior treatment and oesophageal cancer stage I to III, performance status <3, caloric intake >1500âkcalâdayâ1 were included. Chemotherapy, with cisplatin 30âmgâmâ2 and irinotecan 60âmgâmâ2, was administered at days 1, 8, 22, 29, and concurrently with radiotherapy at days 43, 50, 64 and 71. Radiotherapy was delivered with 50 or 50.4âGy in 25 fractions/5 weeks. Forty-three patients were included, 10 stage I, 19 stage II and 14 stage III. Mean age was 59.2 years (range 44â79). A total of 30 out of 43 (69.8%) patients underwent all planned treatment. During induction chemotherapy, 14 severe toxicities of grade 3 or 4 in 10 patients (23.3%) were reported with 57.1% due to haematoxicity. During chemoradiotherapy, 31 severe toxicities of grade 3 or 4 with 64.5% due to haematotoxicity were reported in 18 patients. One toxic death occurred (diarrhoea grade 4). The complete clinical response rate was 58.1% (95% CI: 43.4â72.8%). Overall survival rate at 1 and 2 years was 62.8%, (95% CI, 58.3â77.3%) and 27.9% (95% CI, 13.4â41.3%), respectively. In conclusion, cisplatinâirinotecanâradiotherapy is an active and well-tolerated regimen feasible in out-patients