223 research outputs found
Connecting wind-driven upwelling and offshore stratification to nearshore internal bores and oxygen variability
This study utilizes field observations in southern Monterey Bay, CA, to examine how regional-scale upwelling and changing offshore (shelf) conditions influence nearshore internal bores. We show that the low-frequency wind forcing (e.g., upwelling/relaxation time scales) modifies the offshore stratification and thermocline depth. This in turn alters the strength and structure of observed internal bores in the near-shore. An internal bore strength index is defined using the high-pass filtered potential energy density anomaly in the nearshore. During weak upwelling favorable conditions and wind relaxations, the offshore thermocline deepens. In this case, both the amplitude of the offshore internal tide and the strength of the nearshore internal bores increase. In contrast, during strong upwelling conditions, the offshore thermocline shoals toward the surface, resulting in a decrease in the offshore internal tide amplitude. As a result, cold water accumulates in the nearshore (nearshore pooling), and the internal bore strength index decreases. Empirical orthogonal functions are utilized to support the claim that the bore events contribute to the majority of the variance in cross-shelf exchange and transport in the nearshore. Observed individual bores can drive shock-like drops in dissolved oxygen (DO) with rapid onset times, while extended upwelling periods with reduced bore activity produce longer duration, low DO events
Right ventricular dysfunction after resuscitation predicts poor outcomes in cardiac arrest patients independent of left ventricular function.
OBJECTIVE: Determination of clinical outcomes following resuscitation from cardiac arrest remains elusive in the immediate post-arrest period. Echocardiographic assessment shortly after resuscitation has largely focused on left ventricular (LV) function. We aimed to determine whether post-arrest right ventricular (RV) dysfunction predicts worse survival and poor neurologic outcome in cardiac arrest patients, independent of LV dysfunction.
METHODS: A single-center, retrospective cohort study at a tertiary care university hospital participating in the Penn Alliance for Therapeutic Hypothermia (PATH) Registry between 2000 and 2012.
PATIENTS: 291 in- and out-of-hospital adult cardiac arrest patients at the University of Pennsylvania who had return of spontaneous circulation (ROSC) and post-arrest echocardiograms.
MEASUREMENTS AND MAIN RESULTS: Of the 291 patients, 57% were male, with a mean age of 59 ± 16 years. 179 (63%) patients had LV dysfunction, 173 (59%) had RV dysfunction, and 124 (44%) had biventricular dysfunction on the initial post-arrest echocardiogram. Independent of LV function, RV dysfunction was predictive of worse survival (mild or moderate: OR 0.51, CI 0.26-0.99, p
CONCLUSIONS: Echocardiographic findings of post-arrest RV dysfunction were equally prevalent as LV dysfunction. RV dysfunction was significantly predictive of worse outcomes in post-arrest patients after accounting for LV dysfunction. Post-arrest RV dysfunction may be useful for risk stratification and management in this high-mortality population
Dynactin-dependent cortical dynein and spherical spindle shape correlate temporally with meiotic spindle rotation in Caenorhabditis elegans.
Oocyte meiotic spindles orient with one pole juxtaposed to the cortex to facilitate extrusion of chromosomes into polar bodies. In Caenorhabditis elegans, these acentriolar spindles initially orient parallel to the cortex and then rotate to the perpendicular orientation. To understand the mechanism of spindle rotation, we characterized events that correlated temporally with rotation, including shortening of the spindle in the pole-to pole axis, which resulted in a nearly spherical spindle at rotation. By analyzing large spindles of polyploid C. elegans and a related nematode species, we found that spindle rotation initiated at a defined spherical shape rather than at a defined spindle length. In addition, dynein accumulated on the cortex just before rotation, and microtubules grew from the spindle with plus ends outward during rotation. Dynactin depletion prevented accumulation of dynein on the cortex and prevented spindle rotation independently of effects on spindle shape. These results support a cortical pulling model in which spindle shape might facilitate rotation because a sphere can rotate without deforming the adjacent elastic cytoplasm. We also present evidence that activation of spindle rotation is promoted by dephosphorylation of the basic domain of p150 dynactin
The P174L mutation in human Sco1 severely compromises Cox17-dependent metallation but does not impair copper binding.
International audienceSco1 is a metallochaperone that is required for copper delivery to the Cu(A) site in the CoxII subunit of cytochrome c oxidase. The only known missense mutation in human Sco1, a P174L substitution in the copper-binding domain, is associated with a fatal neonatal hepatopathy; however, the molecular basis for dysfunction of the protein is unknown. Immortalized fibroblasts from a SCO1 patient show a severe deficiency in cytochrome c oxidase activity that was partially rescued by overexpression of P174L Sco1. The mutant protein retained the ability to bind Cu(I) and Cu(II) normally when expressed in bacteria, but Cox17-mediated copper transfer was severely compromised both in vitro and in a yeast cytoplasmic assay. The corresponding P153L substitution in yeast Sco1 was impaired in suppressing the phenotype of cells harboring the weakly functional C57Y allele of Cox17; however, it was functional in sco1delta yeast when the wild-type COX17 gene was present. Pulse-chase labeling of mitochondrial translation products in SCO1 patient fibroblasts showed no change in the rate of CoxII translation, but there was a specific and rapid turnover of CoxII protein in the chase. These data indicate that the P174L mutation attenuates a transient interaction with Cox17 that is necessary for copper transfer. They further suggest that defective Cox17-mediated copper metallation of Sco1, as well as the subsequent failure of Cu(A) site maturation, is the basis for the inefficient assembly of the cytochrome c oxidase complex in SCO1 patients
‘I found out the hard way’: Micro-political workings in professional football
This paper examines the micro-political experiences of Adam (a pseudonym), a newly appointed fitness coach at a Football Association Premier League Club, in his search for acceptance by senior colleagues. Data were collected through a series of in-depth, semi-structured interviews, before being subject to a process of inductive analysis. Goffman’s (1959, 1963) writings on impression management and stigma, Ball’s (1987) micro-political perspective, and Garfinkel’s (1967) notion of status degradation are primarily utilised to make sense of Adam’s perceptions and actions. The findings point to the value of developing coaches’ micro-political understandings, and of including their formal facilitation within given professional preparation programmes. Doing so, it is argued, would better equip coaches for the problematic realities of their practice
Facial expressions depicting compassionate and critical emotions: the development and validation of a new emotional face stimulus set
Attachment with altruistic others requires the ability to appropriately process affiliative and kind facial cues. Yet there is no stimulus set available to investigate such processes. Here, we developed a stimulus set depicting compassionate and critical facial expressions, and validated its effectiveness using well-established visual-probe methodology. In Study 1, 62 participants rated photographs of actors displaying compassionate/kind and critical faces on strength of emotion type. This produced a new stimulus set based on N = 31 actors, whose facial expressions were reliably distinguished as compassionate, critical and neutral. In Study 2, 70 participants completed a visual-probe task measuring attentional orientation to critical and compassionate/kind faces. This revealed that participants lower in self-criticism demonstrated enhanced attention to compassionate/kind faces whereas those higher in self-criticism showed no bias. To sum, the new stimulus set produced interpretable findings using visual-probe methodology and is the first to include higher order, complex positive affect displays
Molecular Classification of the PORTEC-3 Trial for High-Risk Endometrial Cancer:Impact on Prognosis and Benefit From Adjuvant Therapy
PURPOSE The randomized Adjuvant Chemoradiotherapy Versus Radiotherapy Alone in Women With High-Risk Endometrial Cancer (PORTEC-3) trial investigated the benefit of combined adjuvant chemotherapy and radiotherapy (CTRT) versus radiotherapy alone (RT) for women with high-risk endometrial cancer (EC). Because The Cancer Genome Atlas defined an EC molecular classification with strong prognostic value, we investigated prognosis and impact of chemotherapy for each molecular subgroup using tissue samples from PORTEC-3 trial participants. METHODS Paraffin-embedded tissues of 423 consenting patients were collected. Immunohistochemistry for p53 and mismatch repair (MMR) proteins, and DNA sequencing for POLE exonuclease domain were done to classify tumors as p53 abnormal (p53abn), POLE-ultramutated (POLEmut), MMR-deficient (MMRd), or no specific molecular profile (NSMP). The primary end point was recurrence-free survival (RFS). Kaplan-Meier method, log-rank test, and Cox model were used for analysis. RESULTS Molecular analysis was successful in 410 high-risk EC (97%), identifying the 4 subgroups: P53abn EC (n = 93; 23%), POLEmut (n = 51; 12%), MMRd (n = 137; 33%), and NSMP (n = 129; 32%). Five-year RFS was 48% for patients with p53abn EC, 98% for POLEmut EC, 72% for MMRd EC, and 74% for NSMP EC (P <001). The 5-year RFS with CTRT versus RT for p53abn EC was 59% versus 36% (P =019); 100% versus 97% for patients with POLEmut EC (P =637); 68% versus 76% (P =428) for MMRd EC; and 80% versus 68% (P =243) for NSMP EC. CONCLUSION Molecular classification has strong prognostic value in high-risk EC, with significantly improved RFS with adjuvant CTRT for p53abn tumors, regardless of histologic type. Patients with POLEmut EC had an excellent RFS in both trial arms. EC molecular classification should be incorporated in the risk stratification of these patients as well as in future trials to target specific subgroups of patients
Embodying compassion: A virtual reality paradigm for overcoming excessive self-criticism
Virtual reality has been successfully used to study and treat psychological disorders such as phobias and posttraumatic stress disorder but has rarely been applied to clinically-relevant emotions other than fear and anxiety. Self-criticism is a ubiquitous feature of psychopathology and can be treated by increasing levels of self-compassion. We exploited the known effects of identification with a virtual body to arrange for healthy female volunteers high in self-criticism to experience self-compassion from an embodied first-person perspective within immersive virtual reality. Whereas observation and practice of compassionate responses reduced self-criticism, the additional experience of embodiment also increased self-compassion and feelings of being safe. The results suggest potential new uses for immersive virtual reality in a range of clinical conditions.N/
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