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Establishing chronologies of archaeological sites by using a single dating method may not always reliably constrain the age of a deposit or a fossil, as potential biases may naturally arise, particularly in complex sedimentary settings such as caves. In this study, we performed a multi-technique dating approach that targets different materials in two caves from the Cueva Mayor-Cueva del Silo karst system, Sierra de Atapuerca, Spain. Two new fossil teeth from lithostratigraphic unit LU4 (GE-I pit) at Galería de las Estatuas have been dated by combined U-series/ESR and Amino Acid Racemisation (AAR) methods. The former provides ages of 117 ± 13 and 87 ± 9 ka that agree with previous dating studies of this Neandertal site, confirming the assignment of level LU4 to Marine Isotope Stage (MIS) 5. In contrast, AAR analyses produce very scattered ages, pointing to significant post-burial chemical modifications in dentine. A first set of ages is presented for the Cata Litario pit at Sala de los Cíclopes, a palaeontological site formed exclusively of cave bear fossils belonging to the Middle Pleistocene species Ursus deningeri. We provide U-series/ESR and AAR ages for two bear teeth from lithostratigraphic unit LU5, and extended-range luminescence ages for the sediment deposits that host, and immediately underlie and overlie, the bear accumulation. Depositional ages of the sediment were obtained using single-grain thermally-transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains and post-infrared-infrared stimulated luminescence (pIR-IR) dating of K-feldspars. Several speleothems, both in situ and reworked fragments embedded in the different lithostratigraphic units, have additionally been dated by U-series to constrain the timing of the sequence formation. The results indicate that the sediment originally entered the cave between MIS-12 and MIS-10 (444 ± 28 ka to 367 ± 32 ka). Nevertheless, the AAR and U-series/ESR fossil ages, as well as some of the speleothem fragment ages from LUs 5 and 6 are significantly younger. Leaving aside methodologically questionable results for one of the bear tooth samples, the most reliable AAR and U-Series/ESR ages range from 287 ± 23 ka to 256 ± 24, while the speleothem fragments indicate several formation episodes between 444 ± 19 and 284 ± 8 ka. The apparent difference between the U-Series/ESR ages on the fossils and the luminescence ages on the host sediment are not likely to be wholly explained by uncertainties on uranium uptake modelling or gamma dose rate evaluation, and thus is most likely related to taphonomic processes or a complex site formation history. The presence of fossils and eroded speleothem clasts of younger age within these levels is consistent with either an event of prior erosion, transport and resedimentation of LUs 4, 5 and 6, and/or a complex post-depositional mixing history for the stratigraphic sequence at Cata Litario. This study highlights the importance of using different dating methods to reconstruct reliable chronological frameworks, and to understand the geological factors that can affect the dated materials. This includes the accumulation and taphonomic histories of fossils, post-depositional mixing or reworking processes affecting sediments during the residence time within the karst system. [ABSTRACT FROM AUTHOR]

Abstract This study presents single-grain optically stimulated luminescence (OSL) chronologies for the archaeological site of Galería de las Estatuas – the first systematically excavated Middle Palaeolithic site within the karst system of the Sierra de Atapuerca archaeological complex, northern Spain. The single-grain OSL ages are compared with paired single-grain thermally transferred OSL (TT-OSL) dating results for a selection of samples in order to better assess quartz signal bleaching characteristics of endokarstic deposits preserved at Atapuerca. In total, seven luminescence dating samples were collected from four lithostratigraphic units exposed in two excavation pits (GE-I and GE-II). The single-grain OSL equivalent dose (D e) distributions are characterised by generally low overdispersion (20–30%), suggesting appropriate bleaching at deposition. The resultant single-grain OSL ages reveal that the sediment sequence and archaeological remains excavated in pit GE-I accumulated 80–112 ka, while the upper layers of excavation area GE-II were deposited 70–79 ka. The replicate single-grain TT-OSL ages are in agreement with the OSL chronologies at 2σ for three of the four samples investigated; although in all cases the TT-OSL ages were systematically older than their single-grain counterparts. Apparent TT-OSL residual doses (i.e., TT-OSL D e values in excess of their corresponding OSL D e values) of 9–65 Gy were observed for all samples. These excess TT-OSL D e values are generally low in comparison to the natural dose ranges of TT-OSL dating applications undertaken elsewhere in the Atapuerca karst system. The single-grain TT-OSL and OSL dating comparisons build on daylight bleaching experiments and modern analogue studies performed on other Atapuerca exogeneous infill deposits and suggest reasonable potential for TT-OSL signal resetting down to relatively low levels for at least some sediments preserved in the Atapuerca karstic cavities. The quartz single-grain OSL chronologies obtained in this study place the Middle Palaeolithic sequence of Galería de las Estatuas within marine isotope stage (MIS) 5 and the beginning of MIS 4, and provide firm evidence for human occupation of the Sierra de Atapuerca during a previously unreported time period. Highlights • 7 single-grain OSL ages are presented for Galería de las Estatuas archaeological site. • This is the first Middle Palaeolithic cave site at Atapuerca to be dated to MIS 5/4. • Single-grain TT-OSL dating is tested on a sub-set of four Late Pleistocene samples. • 3 of the 4 samples have paired OSL and TT-OSL chronologies in agreement at 2σ. • Our results suggest potential for TT-OSL signal resetting in some cave sediments. [ABSTRACT FROM AUTHOR]

The objectives of this video were to acknowledge the importance of performing a thorough abdominal survey when performing endometriosis surgery and to review the steps of a laparoscopic appendectomy. Video presentation. The patient was in the operating room in lithotomy position throughout surgery. One patient was included in this video presentation. A 43-year-old female undergoing definitive endometriosis surgery. Total laparoscopic hysterectomy, bilateral salpingoophorectomy, lysis of adhesions, excision of endometriosis, and cystoscopy. Procedure completed uneventfully without complications. Postoperative period without complications and reported improvement of pelvic pain 3 weeks after procedure. A thorough survey of the abdomen and pelvis must be performed in search for endometriosis in atypical locations, including the appendix. Patients should be counseled about the possibility of finding appendiceal endometriosis and properly consented for appendectomy. The chosen technique of appendectomy is dependent on surgeon preference and equipment availability. As gynecologic surgeons, we should be prepared to carry out this procedure or have the availability of a general surgeon who can perform it at the time of gynecologic surgery. [ABSTRACT FROM AUTHOR]

The Galería de las Estatuas is a Mousterian site located within the Cueva Mayor-Cueva del Silo karstic system at the Sierra de Atapuerca (Burgos, Spain). This site is characterised by an important Upper Pleistocene stratigraphic sequence in which a large number of lithic artefacts exhibiting clear Mousterian affinities and a rich assemblage of faunal remains have been found. Additionally, this site has yielded a foot phalanx of a clear Neanderthal affinities and its sediment has yielded Neanderthal mitochondrial and nuclear DNA. Two test pits, GE-I and GE-II, have been excavated since 2008 which have been divided in 5 and 2 lithostratigraphical units, respectively. A minimum age of 45 ka cal BP for this site was obtained by radiocarbon dating in GE-II. This chronology was refined using single-grain Optically Stimulated Luminescence (OSL: 80–112 ka in GE-I and 70–79 ka in GE-II) and single-grain thermally transferred OSL (TT-OSL). Although in all case TT-OSL ages were systematically older than their single-grain counterparts. The detrital sequence is sealed by a flowstone whose base is dated to 53.7 ± 3.5 ka cal BP using U-series dating. In order to better constrain the age of this site, nine herbivorous teeth were collected from the whole sedimentary sequence to be dated by the ESR/U-series dating method though only seven provided modelled ages. Six of them were collected from levels 2 to 5 of the GE-I test pit while the last tooth was taken from level 2 of the GE-II test pit. Our results, ranging between 80 and 110 ka, are in agreement with those obtained by single grain TT-OSL and suggest that the sedimentological levels containing Mousterian lithic artefacts and faunal and human remains began to be deposited during the second part of the MIS5. These results fill a temporal gap in the chronology of the Atapuerca sites for which no contemporary MIS5 date was obtained until recently. • First time application of ESR/U-series dating on teeth from the Galería de las Estatuas site. • The importance to contrast the previous dates with others obtained with a different methodology. • These results fill a temporal gap in the chronology of the Atapuerca sites. • The new ESR/U-series ages confirm the Middle Palaeolithic age of this site. [ABSTRACT FROM AUTHOR]

Background: Cardiopulmonary bypass-induced oxidative stress initiates inflammation that can damage the myocardium. This study tested whether cardioplegia enriched with the intermediary metabolite and antioxidant pyruvate dampens postbypass myocardial inflammation. Methods: Pigs were maintained on cardiopulmonary bypass while their hearts were arrested for 60 minutes with 4:1 blood:crystalloid cardioplegia, in which the crystalloid contained 188 mM glucose ± 24 mM pyruvate. Pigs were weaned from bypass after 30 minutes of whole blood reperfusion and recovered for 4 hours. Glutathione (GSH) and glutathione disulfide (GSSG) were measured in coronary sinus plasma to indirectly monitor myocardial GSH redox state (GSH/GSSG). Left ventricular myocardium was sampled 4 hours after cardiopulmonary bypass for analyses of C-reactive protein, matrix metalloproteinases 2 and 9 and tissue inhibitor of metalloproteinase-2 (TIMP-2), and to assess neutrophil infiltration by histology and myeloperoxidase assay. Results: Coronary sinus GSH/GSSG fell 70% after cardiopulmonary bypass with control cardioplegia, but pyruvate cardioplegia produced a robust increase in coronary sinus GSH/GSSG that persisted for 4 hours after bypass. Myocardial C-reactive protein content increased 5.6-fold after control bypass, and neutrophil infiltration and myeloperoxidase activity also increased, but pyruvate-fortified cardioplegia prevented these inflammatory effects. Control cardioplegia lowered myocardial TIMP-2 content by 59% and increased matrix metalloproteinase-9 activity by 35% versus nonbypass sham values, but pyruvate cardioplegia increased TIMP-2 content ninefold versus control cardioplegia and prevented the increase in matrix metalloproteinase-9. Matrix metalloproteinase-2 was not affected by bypass ± pyruvate. Conclusions: Pyruvate-enriched cardioplegia dampens cardiopulmonary bypass-induced myocardial inflammation. Increased GSH/GSSG and TIMP-2 may mediate pyruvate''s effects. [Copyright &y& Elsevier]

Background: Cardioplegic arrest and reperfusion of the myocardium imposes oxidative stress that could potentially inactivate metabolic enzymes and compromise energy production. This study determined the impact of cardioplegic arrest and reperfusion on activities of several oxidant-sensitive enzymes, and tested whether pyruvate, a natural metabolic fuel and antioxidant, mitigates oxidant stress, protects enzymes, and bolsters myocardial energy state after reperfusion. Methods: In situ swine hearts were arrested for 60 minutes with 4:1 blood:crystalloid cardioplegia, and then reperfused for 3 minutes with cardioplegia-free blood with or without approximately 12 mM pyruvate. Tissue metabolites and enzyme activities were measured in left ventricular myocardium snap frozen at 45 minutes of arrest and 3 minutes of reperfusion. Results: The 8-isoprostane content, a measure of lipid peroxidation, sharply increased upon reperfusion, coincident with a 70% decline in redox state of the intracellular antioxidant glutathione. Aconitase and glucose 6-phosphate dehydrogenase activities fell during arrest; creatine kinase and phosphofructokinase were inactivated upon reperfusion. Pyruvate suppressed 8-isoprostane formation, maintained glutathione redox state, and enhanced phosphocreatine phosphorylation potential, a measure of myocardial energy state, during reperfusion. Pyruvate reactivated creatine kinase and aconitase, which are at least partially mitochondrial enzymes, but did not protect the cytosolic enzymes glucose 6-phosphate dehydrogenase and phosphofructokinase. Conclusions: Administration of pyruvate upon reperfusion after cardioplegic arrest mitigates oxidative stress, protects mitochondrial enzymes and increases myocardial energy state. These results support therapeutic application of pyruvate-enhanced reperfusion to prevent cardiac injury after cardioplegic arrest. [Copyright &y& Elsevier]

The marginalization of mountain regions in Mediterranean Europe since the mid-20th Century has triggered important socioeconomic and environmental changes that are putting the survival of highly regulated and environmentally adapted landscapes in jeopardy. We still have only a limited understanding of the driving forces behind these dynamics of change and their final consequences for the structure and character of the landscape. In general, the transformation of the landscape and its causes have been studied at regional and local level and various syntheses have been made for Europe or the Mediterranean as a whole, focusing above all on changes in the use of farmland. The objective of this paper is to provide a holistic view of the changes that have taken place in the landscape in the Euro-Mediterranean region, focusing in particular on the mountains because of their role as heritage reserves and as sources of environmental services. This research involves a systematic review of the evidence about the dynamics of land use change, its underlying drivers and their effects on the landscape. We analyse 53 case studies from 6 countries situated on the northern shores of the Mediterranean. These studies covered a period of around 40 years and were each performed at a local scale. The results reveal that landscape change is caused above all by the abandonment of farmland and reforestation (in over 90% of cases), and by pressure from urban development in the case of coastal and peri-urban mountain ranges. In addition, the dominant dynamics in each case vary depending on the bioclimatic area in question, to the extent that bioclimate has been shown to be an important explanatory factor behind these dynamics. The underlying boosters of change normally act together and those most commonly cited are economic, demographic and geographic. As regards the impacts on the structure and character of the landscape, the dynamics analysed are manifested first and foremost in degradation processes, in an increase in homogenization, which affects above all the most humid bioclimates, and in the fragmentation of open spaces. This analysis provides a general overview of the causes and consequences of the changes in land use in the mountain regions of Mediterranean Europe and raises questions of interest for policy-making that affects the landscape. • We synthesized case study evidence for landscape change in Euro-Mediterranean mountain. • Major landscape change relate to abandonment and reforestation, and also by urban pressure to a lesser extent. • Bioclimates differences are an explanatory variable of the dominant dynamics in the cases studied. • The underlying boosters of landscape change tend to act together. • Landscape structure is being shaped by homogenization, fragmentation and degradation processes. [ABSTRACT FROM AUTHOR]

An esophageal diverticulum is seen in a variety of gastroesophageal conditions, with most having an underlying motility disorder. The diverticulum is diagnosed by combining the patient''s history, physical examination, computed tomographic chest scan, and barium radiography. We present an unusual case of a 43-year-old patient with a history of leiomyoma resection of the esophagus and an ensuing placement of a laparoscopic band for weight loss. One year after banding, persistent dysphagia led to the diagnosis of a large esophageal diverticulum. We believe that this esophageal diverticulum is the largest reported secondary to a laparoscopic band. [Copyright &y& Elsevier]