New detrital petrographic and thermochronologic constraints on the Late Cretaceous-Neogene erosional history of the equatorial margin of Brazil: Implications for the surface evolution of a complex rift margin

The equatorial margin of Brazil is an example of a rift margin with a complex landscape, dominated by an escarpment perpendicular to the continental margin, which testifies to an equally complex rift and post-rift surface and tectonic evolution. This has been the focus of a long debate on the driving mechanism for post-rift tectonics and on the amount of exhumation. This study contributes to this debate with new petrographic and thermochronologic data on 152 samples from three basins, Para-Maranhao, Barreirinhas and Ceara, on the offshore continental platform. Our detrital record goes back to the rift time at ca. 100 Ma ago and outlines three major evolutionary phases of a changing landscape: a rift phase, with the erosion of a moderate rift escarpment, a Late Cretaceous-Palaeogene post-rift phase of major drainage reorganization and significant vertical erosion and a Late Oligocene-to-Recent post-rift phase of moderate vertical erosion and river headwater migration. We estimate that along the equatorial margin of Brazil, over a large onshore area, exhumation since the Late Cretaceous has totalled locally up to 2-2.5 km and since the late Oligocene did not exceed 1 km

Characteristics of Nondisabled Older Patients Developing New Disability Associated with Medical Illnesses and Hospitalization

OBJECTIVE: To identify demographic, clinical, and biological characteristics of older nondisabled patients who develop new disability in basic activities of daily living (BADL) during medical illnesses requiring hospitalization. DESIGN: Longitudinal observational study. SETTING: Geriatric and Internal Medicine acute care units. PARTICIPANTS: Data are from 1,686 patients aged 65 and older who independent in BADL 2 weeks before hospital admission, enrolled in the 1998 survey of the Italian Group of Pharmacoepidemiology in the Elderly Study. MEASUREMENTS: Study outcome was new BADL disability at time of hospital discharge. Sociodemographic, functional status, and clinical characteristics were collected at hospital admission; acute and chronic conditions were classified according to the International Classification of Disease, ninth revision; fasting blood samples were obtained and processed with standard methods. RESULTS: At the time of hospital discharge 113 patients (6.7%) presented new BADL disability. Functional decline was strongly related to patients’ age and preadmission instrumental activities of daily living status. In a multivariate analysis, older age, nursing home residency, low body mass index, elevated erythrocyte sedimentation rate, acute stroke, high level of comorbidity expressed as Cumulative Illness Rating Scale score, polypharmacotherapy, cognitive decline, and history of fall in the previous year were independent and significant predictors of BADL disability. CONCLUSION: Several factors might contribute to loss of physical independence in hospitalized older persons. Preexisting conditions associated with the frailty syndrome, including physical and cognitive function, comorbidity, body composition, and inflammatory markers, characterize patients at high risk of functional decline

The effect of temperature, gradient and load carriage on oxygen consumption, posture and gait characteristics

Purpose The purpose of this experiment was to evaluate the effect of load carriage in a range of temperatures to establish the interaction between cold exposure, the magnitude of change from unloaded to loaded walking and gradient. Methods Eleven participants (19-27 years) provided written informed consent before performing six randomly ordered walking trials in six temperatures (20°C, 10°C, 5°C, 0°C, -5°C and -10°C). Trials involved two unloaded walking bouts before and after loaded walking (18.2 kg) at 4 km.hr⁻¹, on 0% and 10% gradients in 4 minute bouts. Results The change in absolute oxygen consumption (V̇O₂) from the first unloaded bout to loaded walking was similar across all six temperatures. When repeating the second unloaded bout, V̇O₂ at both -5°C and-10°C was greater compared to the first. At -10°C, V̇O₂ was increased from 1.60 ± 0.30 L.min⁻¹ to 1.89 ± 0.51 L.min⁻¹. Regardless of temperature, gradient had a greater effect on V̇O₂ and heart rate (HR) than backpack load. HR was unaffected by temperature. Stride length (SL) decreased with decreasing temperature but trunk forward lean was greater during cold exposure. Conclusion Decreased ambient temperature did not influence the magnitude of change in V̇O₂ from unloaded to loaded walking. However, in cold temperatures, V̇O₂ was significantly higher than in warm conditions. The increased V̇O₂ in colder temperatures at the same exercise intensity is predicted to ultimately lead to earlier onset of fatigue and cessation of exercise. These results highlight the need to consider both appropriate clothing and fitness during cold exposure

Genetic Control of a Central Pattern Generator: Rhythmic Oromotor Movement in Mice Is Controlled by a Major Locus near Atp1a2

Fluid licking in mice is a rhythmic behavior that is controlled by a central pattern generator (CPG) located in a complex of brainstem nuclei. C57BL/6J (B6) and DBA/2J (D2) strains differ significantly in water-restricted licking, with a highly heritable difference in rates (h2≥0.62) and a corresponding 20% difference in interlick interval (mean ± SEM = 116.3±1 vs 95.4±1.1 ms). We systematically quantified motor output in these strains, their F1 hybrids, and a set of 64 BXD progeny strains. The mean primary interlick interval (MPI) varied continuously among progeny strains. We detected a significant quantitative trait locus (QTL) for a CPG controlling lick rate on Chr 1 (Lick1), and a suggestive locus on Chr 10 (Lick10). Linkage was verified by testing of B6.D2-1D congenic stock in which a segment of Chr 1 of the D2 strain was introgressed onto the B6 parent. The Lick1 interval on distal Chr 1 contains several strong candidate genes. One of these is a sodium/potassium pump subunit (Atp1a2) with widespread expression in astrocytes, as well as in a restricted population of neurons. Both this subunit and the entire Na+/K+-ATPase molecule have been implicated in rhythmogenesis for respiration and locomotion. Sequence variants in or near Apt1a2 strongly modulate expression of the cognate mRNA in multiple brain regions. This gene region has recently been sequenced exhaustively and we have cataloged over 300 non-coding and synonymous mutations segregating among BXD strains, one or more of which is likely to contribute to differences in central pattern generator tempo

A precursor of the North Anatolian Fault in the Marmara Sea region

Apatite (U-Th)/He and fission-track analyses of both basement and sedimentary cover samples collected around the Marmara Sea point to the existence of a system of major E–W-trending structural discontinuities active at least from the Late Oligocene. In the Early Pliocene, inception of the present-day North Anatolian Fault (NAF) system in the Marmara region occurred by reactivation of these older tectonic structures. This is particularly evident across the Ganos fault in southern Thrace, as exhumation south of it occurred during the latest Oligocene and north of it during the mid-Miocene. In this area, large tectonic structures long interpreted as the results of Plio-Quaternary NAF-related transpressional deformation (i.e. the Ganos monocline, the Korudag˘ anticline, and the Gelibolu folds) were in fact produced during the Late Oligocene – Early Miocene. The overall lack of significant (U-Th)/He age differences across the NAF indicates that the Early Pliocene inception of strike–slip motion in the Marmara region represents a relatively minor episode. At the scale of the entire Marmara region, the geographic pattern of exhumation ages shown in this study results instead from the complex superposition of older tectonic events including: (i) the amalgamation of Sakarya and Anatolide–Tauride terranes and (ii) Aegean-related extension

IMRT or 3D-CRT in glioblastoma? A dosimetric criterion for patient selection

Intensity modulated radiation therapy (IMRT) is increasingly employed in glioblastoma (GBM) treatment. The present work aimed to assess which clinical-dosimetric scenario could benefit the most from IMRT application, with respect to three-dimensional conformal radiation therapy (3D-CRT). The number of organs at risk (OARs) overlapping the planning target volume (PTV) was the parameter describing the clinical-dosimetric pattern. Based on the results, a dosimetric decision criterion to select the most appropriate treatment technique is provided. Seventeen previously irradiated patients were retrieved and re-planned with both 3D-CRT and IMRT. The prescribed dose was 60 Gy/30fx. The cases were divided into 4 groups (4 patients in each group). Each group represents the scenario where 0, 1, 2 or 3 OARs overlapped the target volume, respectively. Furthermore, in one case, 4 OARs overlapped the PTV. The techniques were compared also in terms of irradiated healthy brain tissue. The results were evaluated by paired t-test. IMRT always provided better target coverage (V95%) than 3D-CRT, regardless the clinical-dosimetric scenario: difference ranged from 0.82% (p = 0.4) for scenario 0 to 7.8% (p = 0.02) for scenario 3, passing through 2.54% (p = 0.18) and 5.93% (p = 0.08) for scenario 1 and 2, respectively. IMRT and 3D-CRT achieved comparable results in terms of dose homogeneity and conformity. Concerning the irradiation of serial-kind OARs, both techniques provided nearly identical results. A statistically significant dose reduction to the healthy brain in favor of IMRT was scored. IMRT seems a superior technique compared to 3D-CRT when there are multiple overlaps between OAR and PTV. In this scenario, IMRT allows for a better target coverage while maintaining equivalent OARs sparing and reducing healthy brain irradiation. The results from our patients dataset suggests that the overlap of three OARs can be used as a dosimetric criterion to select which patients should receive IMRT treatment

Low cholesterol levels are associated with short-term mortality in older patients with ischemic stroke

BACKGROUND: The possible relationship between serum total cholesterol (TC) levels and outcome following ischemic stroke is still controversial. We evaluated the association between TC levels and 30-day mortality in a sample of older patients with acute ischemic stroke. METHODS: We enrolled 490 older patients with severe ischemic stroke consecutively admitted to University Hospital's Internal Medicine or Geriatrics Department. Stroke type was classified according to the Oxfordshire Community Stroke Project. The data recorded included clinical features, medical history, electrocardiogram, and blood analyses. Patients were divided into three groups by TC levels: group I (TC5.2 mmol/L). RESULTS: The overall mortality was 27.7%. Mortality was higher in patients with low TC levels (47.4%) compared with those with normal and high TC levels (23.0% and 24.1%, respectively). The odds ratio (OR) for short-term death was 2.17 (95% confidence interval [CI] 1.22-3.85) in group I compared with group III, after adjustment for age and gender. This result did not change after adjustment for possible confounders (OR 2.87; 95% CI 1.23-6.68). A similar trend was observed after adjustment for the Oxfordshire classification, age, and gender (OR 1.67; 95% CI 0.83-3.33). CONCLUSIONS: Short-term mortality following ischemic stroke is higher in older participants with low TC levels, independent of a large number of factors. Low TC levels might be useful in identifying frail older participants at high risk of stroke short-term mortality

Prescription of anti-oedema agents and short-term mortality in older patients with acute ischaemic stroke

BACKGROUND AND OBJECTIVE: In Western countries, stroke is the third most common cause of death and one of the main causes of disability in individuals aged over 65 years. Mortality at 1 month after stroke is still high, at around 25-30%. Despite the widespread use of anti-oedema agents in clinical practice, there are only a few studies that have investigated the effect of these drugs on stroke outcome. In this study we evaluated the effect of intravenously administered glycerol or mannitol individually and in combination with corticosteroids, on short-term mortality (30 days). The sample included patients aged over 65 years who were admitted to hospital for acute ischaemic stroke. STUDY DESIGN: This was a retrospective cohort study. The odds ratio, estimated by means of multivariate logistic regression method, was used to compare short-term mortality risk across treatment groups after adjusting for possible confounders. METHODS: This study included 442 consecutive patients aged over 65 years with severe ischaemic stroke who were admitted to either the University School of Internal Medicine (Ferrara) or the Geriatric Department (Perugia), Italy, over a 4-year period (1996-2000). All patients underwent a computed tomography (CT) scan of the brain within 72 hours of admission. Stroke type was classified according to the system used by the Oxfordshire Community Stroke Project. The data recorded included: (i) clinical features of stroke; (ii) detailed medical history, including vascular risk factors (arterial hypertension, diabetes mellitus, atrial fibrillation, coronary heart disease, congestive heart failure, alcohol abuse, smoking, previous transient ischaemic attacks or stroke); (iii) 12-lead ECG; and (iv) routine blood analysis and urine tests. RESULTS: No reduction in short-term mortality risk was observed in patients treated with intravenous (IV) glycerol. However, an increase in short-term mortality risk was observed in the patients who were concurrently treated with IV corticosteroids. Similarly, treatment with mannitol did not reduce the risk of short-term mortality; however, concurrent treatment with IV corticosteroids did not show a significant rise in short-term mortality risk. When treatment with IV glycerol and mannitol was considered together, the treatment did not decrease short-term mortality risk, while concurrent therapy with corticosteroids was associated with an increase in short-term mortality risk. CONCLUSION: This study does not support the use of IV osmotic agents such as glycerol or mannitol in the prevention of short-term mortality in older patients with acute ischaemic stroke. Furthermore, our data suggest a possible harmful effect of IV corticosteroids on short-term mortality risk