Transluminal Pillars-Their Origin and Role in the Remodelling of the Zebrafish Caudal Vein Plexus.

Intussusceptive pillars, regarded as a hallmark of intussusceptive angiogenesis, have been described in developing vasculature of many organs and organisms. The aim of this study was to resolve the question about pillar formation and their further maturation employing zebrafish caudal vein plexus (CVP). The CVP development was monitored by in vivo confocal microscopy in high spatio-temporal resolution using the transgenic zebrafish model Fli1a:eGPF//Gata1:dsRed. We tracked back the formation of pillars (diameter ≤ 4 µm) and intercapillary meshes (diameter > 4 µm) and analysed their morphology and behaviour. Transluminal pillars in the CVP arose via a combination of sprouting, lumen expansion, and/or the creation of intraluminal folds, and those mechanisms were not associated directly with blood flow. The follow-up of pillars indicated that one-third of them disappeared between 28 and 48 h post fertilisation (hpf), and of the remaining ones, only 1/17 changed their cross-section area by >50%. The majority of the bigger meshes (39/62) increased their cross-section area by >50%. Plexus simplification and the establishment of hierarchy were dominated by the dynamics of intercapillary meshes, which formed mainly via sprouting angiogenesis. These meshes were observed to grow, reshape, and merge with each other. Our observations suggested an alternative view on intussusceptive angiogenesis in the CVP.

The unique role of the social worker within the Hospital at Home care delivery team.

Hospital at Home (HaH) provides acute, hospital-level care at home and post-discharge follow-up. Through a review of 293 HaH admissions conducted by an urban, multidisciplinary HaH program from 2014 to 2017, we find that the social worker is involved in 71% of admissions and plays a crucial role in pre-emergency department discharge home care and safety screening, home intake, follow-up support, and transition of care to primary care providers and community-based services. We describe the social work activities involved in this model of care and present composite case studies for further illustration.

The critical role of social workers in home-based primary care.

The growing homebound population has many complex biomedical and psychosocial needs and requires a team-based approach to care (Smith, Ornstein, Soriano, Muller, & Boal, 2006). The Mount Sinai Visiting Doctors Program (MSVD), a large interdisciplinary home-based primary care program in New York City, has a vibrant social work program that is integrated into the routine care of homebound patients. We describe the assessment process used by MSVD social workers, highlight examples of successful social work care, and discuss why social workers' individualized care plans are essential for keeping patients with chronic illness living safely in the community. Despite barriers to widespread implementation, such social work involvement within similar home-based clinical programs is essential in the interdisciplinary care of our most needy patients.

Adaptation mechanism of the adult zebrafish respiratory organ to endurance training.

In order to study the adaptation scope of the fish respiratory organ and the O2 metabolism due to endurance training, we subjected adult zebrafish (Danio rerio) to endurance exercise for 5 weeks. After the training period, the swimmer group showed a significant increase in swimming performance, body weight and length. In scanning electron microscopy of the gills, the average length of centrally located primary filaments appeared significantly longer in the swimmer than in the non-trained control group (+6.1%, 1639 µm vs. 1545 µm, p = 0.00043) and the average number of secondary filaments increased significantly (+7.7%, 49.27 vs. 45.73, p = 9e-09). Micro-computed tomography indicated a significant increase in the gill volume (p = 0.048) by 11.8% from 0.490 mm3 to 0.549 mm3. The space-filling complexity dropped significantly (p = 0.0088) by 8.2% from 38.8% to 35.9%., i.e. making the gills of the swimmers less compact. Respirometry after 5 weeks showed a significantly higher oxygen consumption (+30.4%, p = 0.0081) of trained fish during exercise compared to controls. Scanning electron microscopy revealed different stages of new secondary filament budding, which happened at the tip of the primary lamellae. Using BrdU we could confirm that the growth of the secondary filaments took place mainly in the distal half and the tip and for primary filaments mainly at the tip. We conclude that the zebrafish respiratory organ-unlike the mammalian lung-has a high plasticity, and after endurance training increases its volume and changes its structure in order to facilitate O2 uptake.