A 12-year experience in endobronchial intervention using rigid bronchoscopy - account of a tertiary referral centre.

We describe our experience of rigid bronchoscopy and endobronchial intervention at a single tertiary centre over a 12-year period. All rigid bronchoscopy procedures between July 2008 and July 2020 (inclusive) were reviewed. All procedures were performed in cardiothoracic theatres by a designated team under general anaesthesia. 2135 rigid bronchoscopies were performed on 1301 patients aged between 18 and 93 years. Complications occurred in 24 (1.12%) procedures. There was one fatality (0.05%). Haemorrhage >100mls occurred in seven (0.33%) all of which were successfully managed endobronchially. Ten procedures (0.5%) were complicated by pneumothorax and an intercostal drain was required for eight. Five patients required intensive care admission post operatively, all of whom were subsequently discharged from hospital. One patient had stent migration. To the best of our knowledge, this is amongst the largest single centre collection of data available for endobronchial intervention using rigid bronchoscopy. We show that rigid bronchoscopy is a safe and effective procedure when performed in a high-volume specialist centre with designated lists involving a specialist multidisciplinary team.

Large airway complications in COVID-19 pneumonia.

COVID-19 pneumonia can cause respiratory failure which requires specialist management. However the inflammatory nature of the condition and the interventions necessary to manage these patients such as endotracheal intubation and tracheostomy can lead to large airway pathology which may go unrecognised. We describe five of the 44 (11%) consecutive patients referred to our specialist ARDS team between April and June 2020 with confirmed COVID-19 pneumonia who developed diverse large airway pathology which comprised of: supraglottic oedema, tracheal tear, tracheal granulation tissue formation, bronchomalacia, and tracheal diverticulum. Large airway pathology may be underappreciated in severely ill patients with COVID-19 pneumonia and should be considered in patients with unexplained air leak, prolonged need for mechanical ventilatory support, and repeated failed extubation or decannulation. If suspected, such patients should be managed by a team with expertise in large airway intervention and early specialist advice should be sought.

Pulmonary function, computerized tomography features and six-minute walk test at three months in severe COVID-19 patients treated with intravenous pulsed methylprednisolone: a preliminary report.

COVID-19 acute respiratory distress syndrome (ARDS) has a high mortality and few therapeutic options. We present a preliminary report on our experience using high-dose pulsed methylprednisolone in COVID-19 ARDS and three-month outcomes. We performed a retrospective analysis of all patients treated with high-dose methylprednisolone for COVID-19 ARDS and three-month lung function, 6-minutes walking test (6MWT), and computerized tomography (CT) findings. Fifteen patients were treated of which 10 survived to discharge. Reduced diffusion capacity for carbon monoxide (DLCO) was the commonest abnormality in lung function tests and had the lowest mean value. Parenchymal bands were the commonest CT finding and 50% of patients had fibrosis at three months. Mean 6-minutes walk distance (6MWD) was 65.4% predicted and was abnormal in 62.5% of patients. In this cohort of patients with COVID-19 ARDS treated with high-dose methylprednisolone pulses, CT, lung function, and 6MWT abnormalities were unsurprisingly common at three months, although all 10 patients treated early in their disease course survived, a possible therapeutic effect. Further randomised controlled trials are needed to assess the benefits of this treatment.

A 2-step synthesis of Combretastatin A-4 and derivatives as potent tubulin assembly inhibitors.

A series of combretastatin derivatives were designed and synthesised by a two-step stereoselective synthesis by use of Wittig olefination followed by Suzuki cross-coupling. Interestingly, all new compounds (2a-2i) showed potent cell-based antiproliferative activities in nanomolar concentrations. Among the compounds, 2a, 2b and 2e were the most active across three cancer cell lines. In addition, these compounds inhibited the polymerisation of tubulin in vitro more efficiently than CA-4. They caused cell cycle arrest in G2/M phase further confirming their ability to inhibit tubulin polymerisation.

Response of turkey muscle satellite cells to thermal challenge. I. transcriptome effects in proliferating cells.

BACKGROUND: Climate change poses a multi-dimensional threat to food and agricultural systems as a result of increased risk to animal growth, development, health, and food product quality. This study was designed to characterize transcriptional changes induced in turkey muscle satellite cells cultured under cold or hot thermal challenge to better define molecular mechanisms by which thermal stress alters breast muscle ultrastructure. RESULTS: Satellite cells isolated from the pectoralis major muscle of 7-weeks-old male turkeys from two breeding lines (16 weeks body weight-selected and it's randombred control) were proliferated in culture at 33 °C, 38 °C or 43 °C for 72 h. Total RNA was isolated and 12 libraries subjected to RNAseq analysis. Statistically significant differences in gene expression were observed among treatments and between turkey lines with a greater number of genes altered by cold treatment than by hot and fewer differences observed between lines than between temperatures. Pathway analysis found that cold treatment resulted in an overrepresentation of genes involved in cell signaling/signal transduction and cell communication/cell signaling as compared to control (38 °C). Heat-treated muscle satellite cells showed greater tendency towards expression of genes related to muscle system development and differentiation. CONCLUSIONS: This study demonstrates significant transcriptome effects on turkey skeletal muscle satellite cells exposed to thermal challenge. Additional effects on gene expression could be attributed to genetic selection for 16 weeks body weight (muscle mass). New targets are identified for further research on the differential control of satellite cell proliferation in poultry.

Cell-specific trafficking suggests a new role for renal ATP7B in the intracellular copper storage.

Human Cu-ATPases ATP7A and ATP7B maintain copper homeostasis through regulated trafficking between intracellular compartments. Inactivation of these transporters causes Menkes disease and Wilson disease, respectively. In Menkes disease, copper accumulates in kidneys and causes tubular damage, indicating that the renal ATP7B does not compensate for the loss of ATP7A function. We show that this is likely due to a kidney-specific regulation of ATP7B. Unlike ATP7A (or hepatic ATP7B) which traffics from the TGN to export copper, renal ATP7B does not traffic and therefore is unlikely to mediate copper export. The lack of ATP7B trafficking is not on account of the loss of a kinase-mediated phosphorylation or simultaneous presence of ATP7A in renal cells. Rather, the renal ATP7B appears 2-3 kDa smaller than hepatic ATP7B. Recombinant ATP7B expressed in renal cells is similar to hepatic protein in size and trafficking. The analysis of ATP7B mRNA revealed a complex behavior of exon 1 upon amplification, suggesting that it could be inefficiently translated. Recombinant ATP7B lacking exon 1 traffics differently in renal and hepatic cells, but does not fully recapitulate the endogenous phenotype. We discuss factors that may contribute to cell-specific behavior of ATP7B and propose a role for renal ATP7B in intracellular copper storage.

Rapid access to Asp/Glu sidechain hydrazides as thioester precursors for peptide cyclization and glycosylation.

Head-to-sidechain macrocylic peptides, and neoglycopeptides, were readily prepared by site-specific amidation of aspartic and glutamic acid sidechain hydrazides. Hydrazides, serving as latent thioesters, were introduced through regioselective opening of the corresponding Nα-Fmoc protected anhydride precursors.

A specialised cardiorespiratory team approach in the intensive care management of COVID-19 patients: benefit on mortality, diagnosis and management.

BACKGROUND: During the coronavirus pandemic, our intensive care units were faced with large numbers of patients with an unfamiliar disease. To support our colleagues and to assist with diagnosis and treatment, we developed a specialist team. METHODS: The acute respiratory disease support team reviewed 44 consecutive patients referred from the intensive care and coordinated therapies for pulmonary hypertension, pulmonary thrombosis, evolving lung fibrosis and large airway intervention. RESULTS: The mortality for this group was significantly lower (34%) than the total group admitted to critical care as a whole (51%) and for those not reviewed by the team (55%; p=0.012). Pulmonary hypertension was present in 84% of the patients and pulmonary thrombosis in 52%. Thirty-two patients received sildenafil therapy and this was associated with improvement in right heart function in survivors. Ten patients with evolving fibrosis and no evidence of sepsis received high-dose steroid therapy with excellent effect. Five patients developed airway complications requiring intervention. Short time on mechanical ventilation was associated with a poorer outcome (p<0.001). INTERPRETATION: A specialised cardiorespiratory team approach contributes significantly to successful management of severely unwell patients with COVID-19 and offers an important platform for continuity of patient care, education and staff well-being.

Genetic Variants Associated with Cancer Pain and Response to Opioid Analgesics: Implications for Precision Pain Management.

OBJECTIVE: To review the current knowledge on the association of genetic variants with cancer pain. DATA SOURCES: Data-based publications and review articles retrieved from PubMed, CINAHL, and Web of Science, as well as an additional search in Google Scholar. CONCLUSION: Genetic variability can influence differential pain perception and response to opioids in cancer patients, which will have implications in the optimal personalized treatment of cancer pain. More studies are warranted to replicate findings. IMPLICATIONS FOR NURSING PRACTICE: Nurses are poised to educate patients on biomarker testing and interpretation and to use precision pain management strategies based on this information.

Thermal challenge alters the transcriptional profile of the breast muscle in turkey poults.

Extremes in temperature represent environmental stressors that impact the well-being and economic value of poultry. As homeotherms, young poultry with immature thermoregulatory systems are especially susceptible to thermal extremes. Genetic variation and differences in gene expression resulting from selection for production traits, likely contribute to thermal stress response. This study was designed to investigate in vivo transcriptional changes in the breast muscle of young turkey poults from an unselected randombred line and one selected for 16 wk body weight under hot and cold thermal challenge. Newly hatched turkey poults were brooded for 3 d at one of 3 temperatures: control (35°C), cold (31°C), or hot (39°C). Samples of the pectoralis major were harvested and subjected to deep RNA sequencing. Significant differential gene expression was observed in both growth-selected and randombred birds at both temperature extremes when compared to control-brooded poults. Growth-selected birds responded to thermal stress through changes in genes predicted to have downstream transcriptional effects and that would result in reduced muscle growth. Slower growing randombred birds responded to thermal stress through modulation of lipid-related genes, suggesting reduction in lipid storage, transport, and synthesis, consistent with changes in energy metabolism required to maintain body temperature.

Steady-state increase of cAMP-response element binding protein, Rac, and PAK signaling in presenilin-deficient neurons.

Mutations in the genes encoding presenilins (PS1 and PS2) account for the majority of cases of early-onset Alzheimer's disease. PS1 and PS2 form the catalytic center of gamma-secretase, an enzyme responsible for intramembraneous proteolysis of several type I transmembrane proteins. Many gamma-secretase substrates are coupled to intracellular signaling events such as cAMP-response element binding protein and Rac1/p21-activated kinase pathways, which are associated with synaptic function. Here, we have examined the activation of these pathways in neurons lacking PS1 expression or gamma-secretase activity. We found evidence for heightened steady-state activation of cAMP-response element binding protein, Rac1, and p21-activated kinase signaling in PS-deficient neurons. Our study highlights the importance of PS-dependent proteolytic cleavage of gamma-secretase substrates in regulating neuronal signal transduction.

Presenilin attenuates receptor-mediated signaling and synaptic function.

Presenilin (PS) plays an essential role in intramembranous gamma-secretase processing of amyloid precursor protein (APP) and several membrane-bound proteins. Here we report that selective accumulation of a membrane-tethered deleted in colorectal cancer (DCC) derivative (DCC-alpha) correlates with extensive neurite outgrowth in transfected neuroblastoma cells and axodendritic connectivity associated with increased spine density in cortical neurons derived from PS1(-/-) embryos, as well as wild-type neurons treated with gamma-secretase inhibitors. cAMP-dependent signaling was also increased in both the neuroblastoma and cortical neuron systems. As a physiological consequence of increases in axodendritic connectivity and in the magnitude of cAMP-dependent signaling, short- and long-term glutamatergic synaptic transmission was enhanced in PS-deficient neurons. Together, these results demonstrate for the first time that PS-mediated gamma-secretase activity attenuates receptor-mediated intracellular signaling pathways that are critical in regulating glutamatergic synaptic transmission and memory processes.

Environmental metabarcoding reveals heterogeneous drivers of microbial eukaryote diversity in contrasting estuarine ecosystems.

Assessing how natural environmental drivers affect biodiversity underpins our understanding of the relationships between complex biotic and ecological factors in natural ecosystems. Of all ecosystems, anthropogenically important estuaries represent a 'melting pot' of environmental stressors, typified by extreme salinity variations and associated biological complexity. Although existing models attempt to predict macroorganismal diversity over estuarine salinity gradients, attempts to model microbial biodiversity are limited for eukaryotes. Although diatoms commonly feature as bioindicator species, additional microbial eukaryotes represent a huge resource for assessing ecosystem health. Of these, meiofaunal communities may represent the optimal compromise between functional diversity that can be assessed using morphology and phenotype-environment interactions as compared with smaller life fractions. Here, using 454 Roche sequencing of the 18S nSSU barcode we investigate which of the local natural drivers are most strongly associated with microbial metazoan and sampled protist diversity across the full salinity gradient of the estuarine ecosystem. In order to investigate potential variation at the ecosystem scale, we compare two geographically proximate estuaries (Thames and Mersey, UK) with contrasting histories of anthropogenic stress. The data show that although community turnover is likely to be predictable, taxa are likely to respond to different environmental drivers and, in particular, hydrodynamics, salinity range and granulometry, according to varied life-history characteristics. At the ecosystem level, communities exhibited patterns of estuary-specific similarity within different salinity range habitats, highlighting the environmental sequencing biomonitoring potential of meiofauna, dispersal effects or both.

Species-specific effect of macrobenthic assemblages on meiobenthos and nematode community structure in shallow sandy sediments.

Three functionally different macrofaunal species (the filter- and/or surface deposit-feeding polychaete Hediste diversicolor, and the suspension-feeding bivalves Mya arenaria and Cerastoderma glaucum) were introduced as single- and two-species treatments into microcosms containing sandy sediment with a natural meiofaunal community. H. diversicolor is a burrowing species building a system of galleries, C. glaucum lives actively near the sediment surface acting as a biodiffuser and M. arenaria buries deeply and leads a sessile lifestyle. It is shown that H. diversicolor extended the vertical distribution of meiofauna into deeper sediment layers compared to the control and non-Hediste treatments. The response of the nematode community varied significantly among treatments and was dependant on the macrobenthic species composition but not on the species number. Nematode assemblages in all treatments with the polychaete, both in monoculture and with either bivalve, differed significantly from those recorded in other treatments and were more similar than replicates within any other single treatment. H. diversicolor also appeared to have stimulated nematode species diversity. The present study demonstrated that the impact of macrobenthic assemblages on meiofauna is not a simple summation of individual species effects but is species specific.

DNMT3B7, a truncated DNMT3B isoform expressed in human tumors, disrupts embryonic development and accelerates lymphomagenesis.

Epigenetic changes are among the most common alterations observed in cancer cells, yet the mechanism by which cancer cells acquire and maintain abnormal DNA methylation patterns is not understood. Cancer cells have an altered distribution of DNA methylation and express aberrant DNA methyltransferase 3B transcripts, which encode truncated proteins, some of which lack the COOH-terminal catalytic domain. To test if a truncated DNMT3B isoform disrupts DNA methylation in vivo, we constructed two lines of transgenic mice expressing DNMT3B7, a truncated DNMT3B isoform commonly found in cancer cells. DNMT3B7 transgenic mice exhibit altered embryonic development, including lymphopenia, craniofacial abnormalities, and cardiac defects, similar to Dnmt3b-deficient animals, but rarely develop cancer. However, when DNMT3B7 transgenic mice are bred with Emicro-Myc transgenic mice, which model aggressive B-cell lymphoma, DNMT3B7 expression increases the frequency of mediastinal lymphomas in Emicro-Myc animals. Emicro-Myc/DNMT3B7 mediastinal lymphomas have more chromosomal rearrangements, increased global DNA methylation levels, and more locus-specific perturbations in DNA methylation patterns compared with Emicro-Myc lymphomas. These data represent the first in vivo modeling of cancer-associated DNA methylation changes and suggest that truncated DNMT3B isoforms contribute to the redistribution of DNA methylation characterizing virtually every human tumor.

Intracellular targeting of copper-transporting ATPase ATP7A in a normal and Atp7b-/- kidney.

Kidneys regulate their copper content more effectively than many other organs in diseases of copper deficiency or excess. We demonstrate that two copper-transporting ATPases, ATP7A and ATP7B, contribute to this regulation. ATP7A is expressed, to a variable degree, throughout the kidney and shows age-dependent intracellular localization. In 2-wk-old mice, ATP7A is located in the vicinity of the basolateral membrane, whereas in 20-wk-old mice, ATP7A is predominantly in intracellular vesicles. Acute elevation of serum copper, via intraperitoneal injection, results in the in vivo redistribution of ATP7A from intracellular compartments toward the basolateral membrane, illustrating a role for ATP7A in renal response to changes in copper load. Renal copper homeostasis also requires functional ATP7B, which is coexpressed with ATP7A in renal cells of proximal and distal origin. The kidneys of Atp7b(-/-) mice, an animal model of Wilson disease, show metabolic alterations manifested by the appearance of highly fluorescent deposits; however, in marked contrast to the liver, renal copper is not significantly elevated. The lack of notable copper accumulation in the Atp7b(-/-) kidney is likely due to the compensatory export of copper by ATP7A. This interpretation is supported by the predominant localization of ATP7A at the basolateral membrane of Atp7b(-/-) cortical tubules. Our results suggest that both Cu-ATPases regulate renal copper, with ATP7A playing a major role in exporting copper via basolateral membranes and protecting renal tissue against copper overload.