Biomineralisation in the Palaeozoic oceans: evidence for simultaneous crystallisation of high and low magnesium calcite by phacopine trilobites

The chemical composition and microstructure of the calcite cuticles of eleven species of phacopine trilobites have been investigated by electron beam imaging, diffraction, and microanalysis, and results reveal that the lenses of their schizochroal eyes differed significantly in chemical composition from the rest of the cuticle in vivo. Apart from the eye lenses, most cuticles are inferred to have escaped extensive recrystallisation because their constituent crystals are sub-micrometre in size and have a preferred orientation that is consistent between species. Their current compositions of ~1.4 to 2.4 mol% MgCO3 are likely to be close to original values, although as they commonly luminesce and contain detectable manganese and iron, some diagenetic alteration has taken place. The associated lenses have a microstructure that is suitable for focusing light, yet are optically turbid owing to the presence within calcite of micropores and crystals of microdolomite, apatite, celestite and pyrite. The microdolomite indicates that lenses recrystallised from an original high-Mg calcite composition and this is supported by the presence of nanometre-scale modulated microstructures in both the calcite and dolomite. These lenses currently contain ~1 to 6 mol% MgCO3, and by comparison with the proportion of magnesium lost from echinoderm stereom in the same thin sections, may have contained ~7.5 mol% MgCO3 in vivo. In some samples, more extensive diagenetic alteration is evidenced by recrystallisation of the cuticle including lenses to coarse equant calcite or enrichment of the cuticle, but not necessarily the lenses, in magnesium accompanying replacement by a Mg–Fe phyllosilicate. The phacopine trilobites had to modify partition coefficients for magnesium considerably in order to grow lenses with contrasting compositions to the rest of their cuticles, and such a strong vital effect on biomineralisation suggests that incorporation of magnesium was essential for functioning of their calcite optical s

Aspiration therapy for the treatment of obesity: 4-year results of a multicenter randomized controlled trial.

BackgroundThe AspireAssist is the first Food and Drug Administration-approved endoluminal device indicated for treatment of class II and III obesity.ObjectivesWe earlier reported 1-year results of the PATHWAY study. Here, we report 4-year outcomes.SettingUnited States-based, 10-center, randomized controlled trial involving 171 participants with the treatment arm receiving Aspiration Therapy (AT) plus Lifestyle Therapy and the control arm receiving Lifestyle Therapy (2:1 randomization).MethodsAT participants were permitted to continue in the study for an additional year up to a maximum of 5 years providing they maintained at least 10% total weight loss (TWL) from baseline at each year end. For AT participants who continued the study, 5 medical monitoring visits were provided at weeks 60, 68, 76, 90, and 104 and thereafter once every 13 weeks up to week 260. Exclusion criteria were a history of eating disorder or evidence of eating disorder on a validated questionnaire. Follow-up weight, quality of life, and co-morbidities were compared with the baseline levels. In addition, rates of serious adverse event, persistent fistula, withdrawal, and A-tube replacement were reported. All analyses were performed using a per-protocol analysis.ResultsOf the 82 AT participants who completed 1 year, 58 continued to this phase of the trial. Mean baseline body mass index of these 58 patients was 41.6 ± 4.5 kg/m2. At the end of first year (at the beginning of the follow-up study), these 58 patients had a body mass index of 34.1 ± 5.4 kg/m2 and had achieved an 18.3 ± 8.0% TWL. On a per protocol basis, patients experienced 14.2%, 15.3%, 16.6%, and 18.7% TWL at 1, 2, 3, and 4 years, respectively (P < .01 for all). Forty of 58 patients (69%) achieved at least 10% TWL at 4 years or at time of study withdrawal. Improvements in quality of life scores and select cardiometabolic parameters were also maintained through 4 years. There were 2 serious adverse events reported in the second through fourth years, both of which resolved with removal or replacement of the A tube. Two persistent fistulas required surgical repair, representing approximately 2% of all tube removals. There were no clinically significant metabolic or electrolytes disorders observed, nor any evidence for development of any eating disorders.ConclusionsThe results of this midterm study have shown that AT is a safe, effective, and durable weight loss alternative for people with class II and III obesity and who are willing to commit to using the therapy and adhere to adjustments in eating behavior

Action modulates object-based selection

Cueing attention to one part of an object can facilitate discrimination in another part (Experiment 1 [Duncan, j. (1984). Selective attention and the organization of visual information. Journal of Experimental Psychology: General, 113, 501-517]; [Egly, R., Driver, J., and Rafal, R. D. (1994). Shifting visual attention between objects and locations: evidence from normal and parietal lesion divisions. Journal of Experimental Psychology: Human Perception and Performance, 123, 161-177]). We show that this object-based mediation of attention is disrupted when a pointing movement is prepared to the cued part; when a pointing response is prepared to a part of an object, discrimination does not differ between (i) stimuli at locations in the same object but distant to the part where the pointing movement is programmed and (ii) stimuli at locations equidistant from the movement but outside the object (Experiment 2). This remains true even when the pointing movement cannot be performed without first coding the whole object (Experiment 3). Our results indicate that pointing either (i) emphasizes spatial selection at the expense of object-based selection, or (ii) changes the nature of the representations(s) mediating perceptual selection. In addition, the results indicate that there can be a distinct effect on attention of movement to a specific location, separate from the top-down cueing of attention to another position (Experiment 3). Our data highlight the itneractivity between perception and action

‘Emotion is of the essence. … Number one priority’: A nested qualitative study exploring psychosocial adjustment to stroke and aphasia

Background: Stroke and aphasia can have a profound impact on people's lives, and depression is a common, frequently persistent consequence. Social networks also suffer, with poor social support associated with worse recovery. It is essential to support psychosocial well-being post-stroke, and examine which factors facilitate successful adjustment to living with aphasia. Aims: In the context of a feasibility randomized controlled trial of peer-befriending (SUPERB), this qualitative study explores adjustment for people with aphasia in the post-acute phase of recovery, a phase often neglected in previous research. Methods & Procedures: Semi-structured interviews were conducted with 20 people with aphasia and 10 significant others, who were purposively sampled from the wider group of 56 people with aphasia and 48 significant others. Interviews took place in participants’ homes; they were analysed using framework analysis. Outcomes & Results: Participants with aphasia were 10 women and 10 men; their median (interquartile range—IQR) age was 70 (57.5–77.0) years. Twelve participants had mild aphasia, eight moderate–severe aphasia. Significant others were six women and four men with a median (IQR) age of 70.5 (43–79) years. They identified a range of factors that influenced adjustment to aphasia post-stroke. Some were personal resources, including mood and emotions; identity/sense of self; attitude and outlook; faith and spirituality; and moving forward. Significant others also talked about the impact of becoming carers. Other factors were external sources of support, including familial and other relationships; doctors, nurses and hospital communication; life on the ward; therapies and therapists; psychological support, stroke groups; and community and socializing. Conclusions & Implications: To promote adjustment in the acute phase, hospital staff should prioritize the humanizing aspects of care provision. In the post-acute phase, clinicians play an integral role in supporting adjustment and can help by focusing on relationship-centred care, monitoring mental health, promoting quality improvement across the continuum of care and supporting advocacy. What this paper adds What is already known on the subject Anxiety and depression are common consequences of stroke, with depression rates high at 33% at 1 year post-onset. There is evidence that the psychological needs of people with aphasia are even greater than those of the general stroke population. Social support and social networks are also negatively impacted. Few studies have examined adjustment when people are still in hospital or in the early stages of post-stroke life in the community (< 6 months). Further, many stroke studies exclude people with aphasia. What this paper adds to existing knowledge Adjustment to living with stroke and aphasia begins in the early stages of recovery. While this partly depends on personal resources, many factors depend on external sources of help and support. These include doctors, nurses and hospital communication, their experience of life on the ward, and their therapists’ person-centred care. What are the potential or actual clinical implications of this work? Clinicians play an integral role in facilitating people with aphasia to utilize their personal resources and support systems to adjust to life after stroke. They can help by focusing on relationship-centred care, monitoring mental health, promoting quality improvement across the continuum of care and supporting advocacy

Cytotoxic T Lymphocyte Antigen 4 Haploinsufficiency Presenting As Refractory Celiac-Like Disease: Case Report

Primary immunodeficiency may present with treatment-refractory enteropathy. We present two patients with celiac/celiac-like disease diagnosed in early childhood and refractory to the gluten-free diet. One patient had features of multi-system autoimmunity, whereas the other had celiac-like disease as an isolated clinical finding. Both patients underwent genetic testing given disease refractoriness and were ultimately diagnosed with cytotoxic T lymphocyte antigen 4 (CTLA4) haploinsufficiency. They are both now in complete clinical and endoscopic remission on abatacept. CTLA4 haploinsufficiency has incomplete penetrance and significant phenotypic heterogeneity but should be considered in the differential diagnosis of refractory celiac/celiac-like disease, as treatment implications are significant