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1.
Philos Trans A Math Phys Eng Sci ; 381(2249): 20220056, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37150205

RESUMO

The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal timescales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea-ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

2.
S Afr J Surg ; 61(1): 30-38, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37052283

RESUMO

BACKGROUND: Music is played in operating theatres (OTs) throughout the world, though controversy around its use exists. While some clinicians may find background music favourable to the theatre mood and a way to augment surgical performance, there is concern raised over its distracting and noise-creating properties. METHODS: In this prospective observational study, between August and December 2021, 110 surgeons and registrars in South Africa responded to a survey investigating the way they use music, and their perceptions and attitudes towards its effect on the OT environment. RESULTS: In this cohort, 66% were male, 29% were consultants and the most common age range was 30-39 years old. Eighty per cent of respondents reported that music was played at least "sometimes", with 74% reporting that they enjoyed it. Easy Listening was the most played and preferred genre followed by Top 40/Billboard hits. Overwhelmingly, respondents reported that background music in the OT improved temperament, focus, mood, and performance, though over a quarter felt it worsened communication. Thirty-one per cent of respondents reported that the choice of music depended on the type of operation, and 70% would turn music down or off during crises. Those who enjoyed music in their spare time were significantly more likely to enjoy music in the OT and perceive it positively. CONCLUSION: This study provides a window into the surgeons' use of and attitudes to intraoperative music in South Africa. While overall, music is viewed positively by this cohort, some concerns remain regarding communication and distractedness. Further interventional and qualitative studies would be useful.


Assuntos
Música , Humanos , Masculino , Adulto , Feminino , África do Sul , Atitude do Pessoal de Saúde , Salas Cirúrgicas , Inquéritos e Questionários
3.
Biomaterials ; 283: 121464, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35306229

RESUMO

Micropatterned suspension culture creates consistently sized and shaped cell aggregates but has not produced organotypic structures from stable cells, thus restricting its use in accurate disease modeling. Here, we show that organotypic structure is achieved in hybrid suspension culture via supplementation of soluble extracellular matrix (ECM). We created a viable lung organoid from epithelial, endothelial, and fibroblast human stable cell lines in suspension culture. We demonstrate the importance of soluble ECM in organotypic patterning with the emergence of lumen-like structures with airspace showing feasible gas exchange units, formation of branching, perfusable vasculature, and long-term 70-day maintenance of lumen structure. Our results show a dependent relationship between enhanced fibronectin fibril assembly and the incorporation of ECM in the organoid. We successfully applied this technology in modeling lung fibrosis via bleomycin induction and test a potential antifibrotic drug in vitro while maintaining fundamental cell-cell interactions in lung tissue. Our human fluorescent lung organoid (hFLO) model represents features of pulmonary fibrosis which were ameliorated by fasudil treatment. We also demonstrate a 3D culture method with potential of creating organoids from mature cells, thus opening avenues for disease modeling and regenerative medicine, enhancing understanding of lung cell biology in health and lung disease.


Assuntos
Matriz Extracelular , Fibrose Pulmonar , Matriz Extracelular/metabolismo , Fibroblastos , Humanos , Pulmão , Organoides
4.
Clin Exp Dermatol ; 47(1): 125-128, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34236705

RESUMO

Tattoos with blue/black ink show good lightening of pigment after treatment with 1064 nm Q-switched (QS) neodymium-doped yttrium-aluminium-garnet (Nd:YAG) laser. In this randomized trial, we compared the efficacy of a novel three pass, one session procedure (R15 method) with a conventional method for treating blue/black tattoos in darker skin types. Tattoos were treated with 1064 nm QS Nd:YAG Laser with a spot size of 4 mm, fluence of 5 J/cm2 and frequency of 5 Hz. The tattoo pigment lightening was comparable with both methods. Thread-like tattoos had significantly better pigment lightening with fewer side effects than the broad band-like tattoos. We would like to recommend the R15 method of the QS Nd:YAG laser for thread-like tattoos, which can save patients' time, cut short the frequency of their hospital visits and, more importantly, decrease the cost involved in it.


Assuntos
Lasers de Estado Sólido/uso terapêutico , Pigmentação da Pele , Pele/efeitos da radiação , Tatuagem , Vesícula/etiologia , Cicatriz/etiologia , Humanos , Lasers de Estado Sólido/efeitos adversos , Lesões por Radiação/etiologia
5.
Clin Radiol ; 76(9): 710.e9-710.e14, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34119304

RESUMO

AIM: To assesses whether utilising bone marrow oedema (BMO) maps improved fracture read times and reader confidence in a large series of acute lower extremity trauma dual-energy computed tomography (DECT) studies. MATERIALS AND METHODS: One hundred and six DECT studies, including 60 fracture cases and 46 non-fracture cases, were evaluated retrospectively in this cross-sectional study. Three-dimensional (3D) BMO maps were generated for each study and coded to display skeletal anatomy in blue and marrow oedema in green. Studies were interpreted by two readers in two timed stages (without and with BMO maps). Readers identified the number, anatomical location, and comminution of fractures. Reader confidence (five-point Likert scale) for fracture identification and anatomical regions where oedema was present was also recorded. RESULTS: Decreased read times (p<0.01) were observed when readers utilised BMO maps for their fracture search. The presence of oedema on BMO maps corresponded with associated fracture in 75.7% reads. No differences in reader confidence were observed as a result of using this BMO-guided technique (>95%, 5/5 for both readers with and without the aid of BMO maps). CONCLUSIONS: DECT BMO maps improve the speed of radiological identification of suspected acute lower extremity fractures with preserved reader confidence. It may help emergent detection of fractures, important for patient management and outcomes.


Assuntos
Medula Óssea/diagnóstico por imagem , Edema/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Medula Óssea/fisiopatologia , Estudos Transversais , Edema/complicações , Edema/fisiopatologia , Feminino , Fraturas Ósseas/complicações , Humanos , Imageamento Tridimensional/métodos , Extremidade Inferior/diagnóstico por imagem , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Tempo
7.
Sci Rep ; 8(1): 7424, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743503

RESUMO

We present qSR, an analytical tool for the quantitative analysis of single molecule based super-resolution data. The software is created as an open-source platform integrating multiple algorithms for rigorous spatial and temporal characterizations of protein clusters in super-resolution data of living cells. First, we illustrate qSR using a sample live cell data of RNA Polymerase II (Pol II) as an example of highly dynamic sub-diffractive clusters. Then we utilize qSR to investigate the organization and dynamics of endogenous RNA Polymerase I (Pol I) in live human cells, throughout the cell cycle. Our analysis reveals a previously uncharacterized transient clustering of Pol I. Both stable and transient populations of Pol I clusters co-exist in individual living cells, and their relative fraction vary during cell cycle, in a manner correlating with global gene expression. Thus, qSR serves to facilitate the study of protein organization and dynamics with very high spatial and temporal resolutions directly in live cell.


Assuntos
Ciclo Celular , Análise de Dados , Ensaios Enzimáticos/métodos , RNA Polimerase I/metabolismo , Software , Algoritmos , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Naftiridinas/farmacologia , Transcrição Gênica/efeitos dos fármacos
8.
Data Brief ; 16: 1051-1055, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29326967

RESUMO

Sensing ability of caffeine interaction with Phe-Phe annotates (PNTs), is presented (Govindhan et al., 2017; Karthikeyan et al., 2014; Tavagnacco et al., 2013; Kennedy et al., 2011; Wang et al., 2017) [1-5] in this data set. Investigation of synthesized caffeine carrying peptide nanotubes are carried out by FT-Raman spectral analysis and high resolution transmission electron microscopy (HR-TEM). Particle size of the caffeine loaded PNTs is < 40 nm. The FT-Raman spectrum signals are enhanced in the region of 400-1700 cm-1. These data are ideal tool for the applications like biosensing and drug delivery research (DDS).

9.
Biochem Biophys Rep ; 10: 165-171, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28670627

RESUMO

LR8 gene was first reported in a subpopulation of cultured human lung fibroblasts expressing the receptor for C1q-globular domain, and it was not detectable in cultured endothelial cells and smooth muscle cells. LR8 mRNA levels were higher in fibrotic lungs. In this study we assessed LR8 production in human tissues and determined if the distribution of fibroblasts producing LR8 is affected in fibrosis. Normal and fibrotic tissue sections from human liver, lung and kidneys were immunostained with antibodies to LR8 and examined for the presence of fibroblasts staining positively and negatively. The cells were also examined for co-expression of α-smooth muscle actin (SMA), a marker for myofibroblasts. The results showed that LR8 was expressed by fibroblasts, smooth muscle cells, endothelial cells, bile duct cells, pulmonary alveolar cells and distal and proximal kidney tubule cells. Connective tissues of normal and fibrotic tissues contained fibroblasts staining positively and negatively with anti- LR8 antibody. The number of LR8-positive cells was higher in fibrotic tissues, but differences were not statistically significant. Fibroblasts producing both LR8 and SMA were present in higher numbers in fibrotic tissues as compared to normal tissues and the differences were statistically significant (p<0.05). Our results show that fibroblast subtypes differing in LR8 expression are present in human tissues, and that in fibrotic tissues cells co-expressing LR8 and SMA are present. Our results indicate that LR8 expressing cells may participate in the early stages of fibrotic diseases and that fibroblasts expressing LR8, not LR8 negative cells, have potential to become myofibroblasts in fibrotic tissues.

10.
Biomaterials ; 125: 54-64, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28231508

RESUMO

Hematopoietic stem cells (HSC) reside in unique bone marrow niches and are influenced by signals from surrounding cells, the extracellular matrix (ECM), ECM-bound or diffusible biomolecules. Here we describe the use of a three-dimensional hydrogel to alter the balance of HSC-generated autocrine feedback and paracrine signals generated by co-cultured niche-associated cells. We report shifts in HSC proliferation rate and fate specification in the presence of lineage positive (Lin+) niche cells. Hydrogels promoting autocrine feedback enhanced expansion of early hematopoietic progenitors while paracrine signals from Lin+ cells increased myeloid differentiation. We report thresholds where autocrine vs. paracrine cues alter HSC fate transitions, and were able to selectively abrogate the effects of matrix diffusivity and niche cell co-culture via the use of inhibitory cocktails of autocrine or paracrine signals. Together, these results suggest diffusive biotransport in three-dimensional biomaterials are a critical design element for the development of a synthetic stem cell niche.


Assuntos
Comunicação Autócrina/fisiologia , Matriz Extracelular/química , Células-Tronco Hematopoéticas/fisiologia , Hidrogéis/química , Comunicação Parácrina/fisiologia , Nicho de Células-Tronco/fisiologia , Animais , Materiais Biomiméticos/química , Linhagem da Célula/fisiologia , Feminino , Células-Tronco Hematopoéticas/citologia , Camundongos , Camundongos Endogâmicos C57BL
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