The well documented fossil record of European Quaternary freshwater gastropods offers a unique resource for continental-scale biogeographical analyses. Here, we assembled a dataset including 338 ...freshwater gastropod taxa from 1058 localities across Europe, which we used to explore how freshwater gastropod communities varied in space and time across six distinct time intervals of the Quaternary, i.e. Gelasian, Calabrian, Middle Pleistocene, Last Interglacial, Last Glacial and Holocene. We took into consideration both species richness and qualitative structural patterns, comparing turnover rates between time intervals and examining variations in community nestedness-segregation patterns. Species richness differed significantly between time intervals. The Early Pleistocene showed the highest diversity, likely because of the contribution of long-lived aquatic systems like the lakes Bresse and Tiberino that promoted speciation and endemism. The rich Middle to Late Pleistocene and Holocene assemblages were mostly linked to fluvial and/or lacustrine systems with short temporal durations. We identified a major turnover event at the Plio-Pleistocene boundary, related to the demise of long-lived lakes and of their rich, endemic faunas at the end of the Pliocene. In the subsequent intervals, little or no turnover was observed. We also observed a pattern of high segregation in Early Pleistocene communities, associated with the abundance of endemic species with small distribution ranges, and reflecting the provincial character of the aquatic freshwater systems at that time. This structured pattern disintegrated gradually towards the Middle Pleistocene and remained unstructured up to present. In particular, spatial patterns of community nestedness-segregation in the Last Interglacial and Holocene suggest a random recolonization of freshwater habitats mostly by generalist species following deglaciation.
•Richness of European freshwater snails is not constant throughout the Quaternary.•Rise and demise of long-lived lakes controls Quaternary snails' turnover.•Iterative process of glacial cycles affects the structure of snails' distribution.•Distribution patterns after deglaciation result from random recolonization.•Generalist species with wide ranges prevail during the Late Pleistocene & Holocene.
Virtual endoscopy (vE) allows simulated three-dimensional (3-D) visualisation of anatomical structures by computerised reconstruction of radiological images. The aim of this study was to evaluate the ...feasibility of vE and its potential benefits for endoscopic transsphenoidal pituitary surgery. vE was realised using a commercially available ray-casting software plugin of a picture archiving and communications system (PACS). For this study, the vE system was enhanced with volume segmentation, transparency and cutting tools. The data for vE were derived from high resolution computed tomography (CT) scans of 22 patients with pituitary pathology (20 pituitary adenomas, 2 Rathke's cleft cysts) preoperatively. Anatomic structures were identified on vE images and compared with the intraoperative endoscopic views. The simulated 3-D vE images were found to be comparable to the intraoperative endoscopic anatomy in terms of distortion and angle of view. vE was found to be particularly useful for the preoperative depiction of 1) the nasal anatomy and its variations for choosing the side of the approach, 2) the sphenoid sinus septae and chambers for improved intraoperative orientation, 3) the transparent 3-D simulated visualisation of the pituitary gland, tumour and adjacent anatomic structures in relation to the sphenoid sinus landmarks for planning the opening of the sellar floor. We conclude that vE harbours the potential to become a valuable tool in endoscopic pituitary surgery for training purposes and preoperative planning. Furthermore, vE may add to the safety of interventions in case of anatomic variations.
Cytotoxic drugs have been used in the therapy of malignant tumors for the last 70 years. However, side effects of cytotoxic drugs are very common and often dose-limiting. Although many protocols have ...been optimized, side effects are still frequently life-threatening. Nausea and vomiting are among the most frequently reported side effects, in addition to mucositis and fatigue. Bone marrow toxicity can lead to neutropenic sepsis, thrombocytopenic bleeding, or anemia with the respective sequelae. In addition to these unspecific side effects, organ toxicity is class or drug specific and may involve the kidney, liver, heart, lung, skin, or central nervous system. As most protocols can be administered on an outpatient basis, knowledge of these side effects is important for the general internist.
In peripherally chemodenervated, vagotomized, chloralose-anesthetized cats, hypoxia can produce central cardiorespiratory depression or excitation depending on severity. We monitored phrenic and ...cervical sympathetic neurograms during either hypoxic depression or gasping and 30 min of subsequent isocapnic reoxygenation to determine whether the response of these outputs during hypoxia predicts their activity during recovery. Three levels of hypoxic response were produced in cats: 1) reduction of phrenic neurogram amplitude (PNA) by 30% fractional inspired O2 (FIO2) = 14-18%); 2) production of phrenic apnea (FIO2 = 9-10%); and 3) hypoxic gasping (FIO2 = 6-8%). Recovery from the milder levels of hypoxia was characterized by transient (< 10 min) depression of PNA and inspiratory synchronous sympathetic activity. Respiratory frequency was unaffected or only transiently depressed. Tonic sympathetic activity was unaffected. During reoxygenation after gasping, both PNA and inspiratory synchronous sympathetic activity were initially increased by 80% over control levels and respiratory frequency was depressed. Tonic sympathetic activity increased during hypoxia but returned to control levels after a brief undershoot on reoxygenation. All variables returned to control levels within 15 min. Measurement of medullary extracellular K+ concentration (K+e) in a separate group of cats indicated that a significant increase in this variable was associated with hypoxic gasping but was not correlated with PNA augmentation during reoxygenation. We hypothesize that increased K+e coincident with gasping may trigger a postanoxic potentiation of respiratory premotor neurons similar to that described in hippocampus.
Seventy-one patients with acute myeloid leukemia (AML), most of them (63/71) considered ineligible for conventional allogeneic hematopoietic stem cell transplantation (HSCT), were enrolled into a ...phase 2 study on reduced-intensity myeloablative conditioning with fractionated 8-Gy total body irradiation (TBI) and fludarabine (120 mg/m2). Patients received mobilized peripheral blood stem cells (n = 68) or bone marrow (n = 3) from siblings (n = 39) or unrelated donors (n = 32). Thirty-six patients received a transplant in complete remission (CR) and 35 had untreated or refractory disease (non-CR). Median patient age was 51 years (range, 20-66 years). Sustained engraftment was attained in all evaluable patients. With a median follow-up of 25.9 months (range, 3.7-61.2 months) in surviving patients, probabilities of overall survival for patients who received a transplant in CR and non-CR were 81% and 21% at 2 years, respectively. Relapse-free survival rates were 78% and 16%. The cumulative incidence of nonrelapse mortality (NRM) in CR patients was 8% at 2 years and beyond but amounted to 37% at 2 years in non-CR patients. Outcome data in this poor-risk population indicate that allogeneic HSCT from related or unrelated donors with 8-Gy TBI/fludarabine conditioning is feasible with low NRM and preserved antileukemic activity in AML patients in first or later CR.
PDF
