Healthcare providers' challenges during the coronavirus disease (COVID-19) pandemic: A qualitative approach.

The uncertain trajectory of COVID-19 has led to significant psychosocial impacts on nurses and other healthcare providers. Given the critical role of these providers in pandemic response, this study sought to gain a better understanding of the challenges faced by healthcare providers caring for adult patients during the COVID-19 pandemic. A descriptive, qualitative study was conducted via semi-structured interviews. A purposeful sample of healthcare providers (n = 23) caring for patients during the COVID-19 pandemic was recruited to participate in interviews via snowball sampling and an information systems-supported recruiting process (e-recruiting). Thematic analysis revealed four themes: (1) Managing isolation, fear, and increased anxiety; (2) adapting to changes in healthcare practice and policy; (3) addressing emotional and physical needs of patients and their families; and (4) navigating evolving workplace safety. New evidence was introduced about nurses practicing outside their usual role. Nurses and other healthcare providers consistently reported increased anxiety during the pandemic. Hospital administrations can proactively support healthcare providers during this and future pandemics by ensuring access to mental health programs, standardizing communication, and developing plans that address equipment and supply availability.

Leadership, professional quality of life and moral distress during COVID-19: A mixed-methods approach.

AIM: To understand the impact of professional stressors on nurses' and other health care providers' professional quality of life and moral distress as they cared for patients during the COVID-19 pandemic. BACKGROUND: Health care providers caring for patients during the COVID-19 pandemic are at increased risk of decreased professional quality of life and increased moral distress. METHODS: A convergent mixed-methods design and snowball sampling was used to collect survey data (n = 171) and semi-structured interviews (n = 23) among health care providers working in the inpatient setting. RESULTS: Perceived lack of support from executive leadership, access to personal protective equipment and constantly changing guidelines led to decreased professional quality of life and increased moral distress among health care providers. CONCLUSION: Findings from this study indicate that shared governance, disaster management training and enhanced communication may assist executive leadership to reduce the likelihood of decreased professional quality of life and increased moral distress in front line health care providers. IMPLICATIONS FOR NURSING MANAGEMENT: Following the principles of shared governance may assist executive leadership to promote and acknowledge the significance of the role of health care providers at the bedside. Additionally, disaster management training and open communication are crucial to ensure that health care providers are adequately informed and supported at the bedside.

Body mass-specific Na+-K+-ATPase activity in the medullary thick ascending limb: implications for species-dependent urine concentrating mechanisms.

In general, the mammalian whole body mass-specific metabolic rate correlates positively with maximal urine concentration (Umax) irrespective of whether or not the species have adapted to arid or mesic habitat. Accordingly, we hypothesized that the thick ascending limb (TAL) of a rodent with markedly higher whole body mass-specific metabolism than rat exhibits a substantially higher TAL metabolic rate as estimated by Na+-K+-ATPase activity and Na+-K+-ATPase α1-gene and protein expression. The kangaroo rat inner stripe of the outer medulla exhibits significantly higher mean Na+-K+-ATPase activity (~70%) compared with two rat strains (Sprague-Dawley and Munich-Wistar), extending prior studies showing rat activity exceeds rabbit. Furthermore, higher expression of Na+-K+-ATPase α1-protein (~4- to 6-fold) and mRNA (~13-fold) and higher TAL mitochondrial volume density (~20%) occur in the kangaroo rat compared with both rat strains. Rat TAL Na+-K+-ATPase α1-protein expression is relatively unaffected by body hydration status or, shown previously, by dietary Na+, arguing against confounding effects from two unavoidably dissimilar diets: grain-based diet without water (kangaroo rat) or grain-based diet with water (rat). We conclude that higher TAL Na+-K+-ATPase activity contributes to relationships between whole body mass-specific metabolic rate and high Umax. More vigorous TAL Na+-K+-ATPase activity in kangaroo rat than rat may contribute to its steeper Na+ and urea axial concentration gradients, adding support to a revised model of the urine concentrating mechanism, which hypothesizes a leading role for vigorous active transport of NaCl, rather than countercurrent multiplication, in generating the outer medullary axial osmotic gradient.

Participatory monitoring to connect local and global priorities for forest restoration.

New global initiatives to restore forest landscapes present an unparalleled opportunity to reverse deforestation and forest degradation. Participatory monitoring could play a crucial role in providing accountability, generating local buy in, and catalyzing learning in monitoring systems that need scalability and adaptability to a range of local sites. We synthesized current knowledge from literature searches and interviews to provide lessons for the development of a scalable, multisite participatory monitoring system. Studies show that local people can collect accurate data on forest change, drivers of change, threats to reforestation, and biophysical and socioeconomic impacts that remote sensing cannot. They can do this at one-third the cost of professionals. Successful participatory monitoring systems collect information on a few simple indicators, respond to local priorities, provide appropriate incentives for participation, and catalyze learning and decision making based on frequent analyses and multilevel interactions with other stakeholders. Participatory monitoring could provide a framework for linking global, national, and local needs, aspirations, and capacities for forest restoration.

Isolation and perfusion of rat inner medullary vasa recta.

Outer medullary isolated descending vasa recta have proven to be experimentally tractable, and consequently much has been learned about outer medullary vasa recta endothelial transport, pericyte contractile mechanisms, and tubulovascular interactions. In contrast, inner medullary vasa recta have never been isolated from any species, and therefore isolated vasa recta function has never been subjected to in vitro quantitative evaluation. As we teased out inner medullary thin limbs of Henle's loops from the Munich-Wistar rat, we found that vasa recta could be isolated using similar protocols. We isolated ∼30 inner medullary vasa recta from 23 adult male Munich-Wistar rats and prepared them for brightfield or electron microscopy, gene expression analysis by RT-PCR, or isolated tubule microperfusion. Morphological characteristics include branching and nonbranching segments exhibiting a thin endothelium, axial surface filaments radiating outward giving vessels a hairy appearance, and attached interstitial cells. Electron microscopy shows multiple cells, tight junctions, and either continuous or fenestrated endothelia. Isolated vasa recta express genes encoding the urea transporter UT-B and/or the fenestral protein PV-1, genes expressed in descending or ascending vasa recta, respectively. The transepithelial NaCl permeability (383.3 ± 60.0 × 10(-5) cm/s, mean ± SE, n = 4) was determined in isolated perfused vasa recta. Future quantitative analyses of isolated inner medullary vasa recta should provide structural and functional details important for more fully understanding fluid and solute flows through the inner medulla and their associated regulatory pathways.

Transepithelial water and urea permeabilities of isolated perfused Munich-Wistar rat inner medullary thin limbs of Henle's loop.

To better understand the role that water and urea fluxes play in the urine concentrating mechanism, we determined transepithelial osmotic water permeability (Pf) and urea permeability (Purea) in isolated perfused Munich-Wistar rat long-loop descending thin limbs (DTLs) and ascending thin limbs (ATLs). Thin limbs were isolated either from 0.5 to 2.5 mm below the outer medulla (upper inner medulla) or from the terminal 2.5 mm of the inner medulla. Segment types were characterized on the basis of structural features and gene expression levels of the water channel aquaporin 1, which was high in the upper DTL (DTLupper), absent in the lower DTL (DTLlower), and absent in ATLs, and the Cl-(1) channel ClCK1, which was absent in DTLs and high in ATLs. DTLupper Pf was high (3,204.5 ± 450.3 µm/s), whereas DTLlower showed very little or no osmotic Pf (207.8 ± 241.3 µm/s). Munich-Wistar rat ATLs have previously been shown to exhibit no Pf. DTLupper Purea was 40.0 ± 7.3 × 10(-5) cm/s and much higher in DTLlower (203.8 ± 30.3 × 10(-5) cm/s), upper ATL (203.8 ± 35.7 × 10(-5) cm/s), and lower ATL (265.1 ± 49.8 × 10(-5) cm/s). Phloretin (0.25 mM) did not reduce DTLupper Purea, suggesting that Purea is not due to urea transporter UT-A2, which is expressed in short-loop DTLs and short portions of some inner medullary DTLs close to the outer medulla. In summary, Purea is similar in all segments having no osmotic Pf but is significantly lower in DTLupper, a segment having high osmotic Pf. These data are inconsistent with the passive mechanism as originally proposed.

Basolateral uptake of nucleosides by Sertoli cells is mediated primarily by equilibrative nucleoside transporter 1.

The blood-testis barrier (BTB) prevents the entry of many xenobiotic compounds into seminiferous tubules thereby protecting developing germ cells. Understanding drug transport across the BTB may improve drug delivery into the testis. Members of one class of drug, nucleoside reverse transcriptase inhibitors (NRTIs), do penetrate the BTB, presumably through interaction with physiologic nucleoside transporters. By investigating the mechanism of nucleoside transport, it may be possible to design other drugs to bypass the BTB in a similar manner. We present a novel ex vivo technique to study transport at the BTB that employs isolated, intact seminiferous tubules. Using this system, we found that over 80% of total uptake by seminiferous tubules of the model nucleoside uridine could be inhibited by 100 nM nitrobenzylmercaptopurine riboside (NBMPR, 6-S-[(4-nitrophenyl)methyl]-6-thioinosine), a concentration that selectively inhibits equilibrative nucleoside transporter 1 (ENT1) activity. In primary cultured rat Sertoli cells, 100 nM NBMPR inhibited all transepithelial transport and basolateral uptake of uridine. Immunohistochemical staining showed ENT1 to be located on the basolateral membrane of human and rat Sertoli cells, whereas ENT2 was located on the apical membrane of Sertoli cells. Transepithelial transport of uridine by rat Sertoli cells was partially inhibited by the NRTIs zidovudine, didanosine, and tenofovir disoproxil fumarate, consistent with an interaction between these drugs and ENT transporters. These data indicate that ENT1 is the primary route for basolateral nucleoside uptake into Sertoli cells and a possible mechanism for nucleosides and nucleoside-based drugs to undergo transepithelial transport.

Molecular cloning of rabbit organic cation transporter rbOCT2 and functional comparisons with rbOCT1.

Multiple organic cation transporters (OCTs) are present in rabbit kidney and may play different functional roles. We cloned rabbit OCT2 (rbOCT2) and compared its function with that of rabbit OCT1 (rbOCT1). In transiently transfected COS-7 cells, rbOCT1 and rbOCT2 mediated uptake of [3H]tetraethylammonium (TEA) with K(t) values of 188 and 125 microM, respectively. n-Tetraalkylammonium compounds showed similar affinities for the two homologs, with IC50 values for inhibition of OCT1- and OCT2-mediated [3H]TEA transport, respectively, of 4,538 and 1,395 microM for tetramethylammonium, 88.5 and 3.9 microM for tetrapropylammonium, 13.9 and 5.3 microM for tetrabutylammonium, and 8.8 and 7.6 microM for tetrapentylammonium. However, the transporters had very different affinities for cimetidine (CIM): IC50 of 916 and 5.7 microM for rbOCT1 and rbOCT2, respectively. CIM inhibition of TEA uptake into single S2 segments of rabbit proximal tubule was used to estimate the contributions of OCT1 and OCT2 to basolateral organic cation uptake. The median IC50 for CIM inhibition of TEA uptake was 12.3 microM, suggesting that OCT2 is the major contributor to basolateral organic cation transport in the S2 segment of proximal tubule in rabbit kidney.

Functional mapping of rbOCT1 and rbOCT2 activity in the S2 segment of rabbit proximal tubule.

A strategy was developed to determine the distribution of activity mediated by the organic cation (OC) transporters OCT1 and OCT2 in rabbit renal proximal tubule (RPT). Both transporters displayed similar affinities for tetraethylammonium (TEA; in CHO-K1 cells, TEA concentrations that resulted in half-maximal transport were 19.9 and 34.5 microM for OCT1 and OCT2, respectively). Similarly, some OCs showed little capacity to discriminate between the two processes (IC50 values for ephedrine of 13.6 and 24.2 microM for OCT1 and OCT2, respectively). However, OCT2 had a higher affinity for cimetidine and [2-(4-nitro-2,1,3-benzoxadiazol-7-yl) aminoethyl]trimethylammonium (NBD-TMA; 1.3 and 1.4 microM, respectively) than did OCT1 (97.3 and 108 microM, respectively). Conversely, OCT1 had a higher affinity for tyramine and pindolol than did OCT2 (21.2 and 2.4 vs. 361 and 50 microM, respectively). We designated these as "discriminatory inhibitors" and used them to determine the relative contribution of OCT1 and OCT2 for TEA transport in single S2 segments of rabbit RPT. Cimetidine and NBD-TMA were high-affinity inhibitors of TEA transport in S2 segments (median IC50 values of 12.3 and 1.4 microM, respectively); in comparison, tyramine and pindolol were low-affinity inhibitors (265 and 69.3 microM, respectively). These IC50 values were sufficiently close to those for OCT2 to support the conclusion that TEA transport in the S2 segment of rabbit RPT is dominated by OCT2. However, the profile of inhibition of tyramine (an OCT1-selective substrate) transport in single S2 segments indicated that, despite a comparatively low level of expression, OCT1 can play a dominant role in the uptake of selected OC substrates.

Functional map of TEA transport activity in isolated rabbit renal proximal tubules.

The organic cation (OC) transporters OCT1 and OCT2 are suspected of mediating substrate entry from the blood into proximal tubule cells as the first step in renal secretion of OCs. We examined the contribution of each process in different rabbit renal proximal tubule (RPT) segments, taking advantage of the fact that rabbit orthologs of OCT1 and OCT2 can be distinguished by the high affinity of the former for tyramine (TYR) and of the latter for cimetidine (CIM). We verified that TEA uptake, for which both transporters share a similar affinity, is relatively constant in all three segments (apparent inhibitory constant of 33, 74, and 30 microM and maximal rate of mediated TEA uptake of 0.8, 1.0, and 1.2 pmol x mm(-1) x min(-1) in S1, S2, and S3, respectively). In the S1 segment, TYR was a more effective inhibitor of TEA uptake than CIM (IC50 values of 39 and 328 microM, respectively), implicating OCT1 as the predominant pathway for TEA transport. The opposite profiles were noted in the S2 segment (IC50 values of 302 and 20 microM for TYR and CIM, respectively) and S3 segment (IC50 values of 2,900 and 54 microM for TYR and CIM, respectively), suggesting that OCT2 is the predominant TEA transporter in the later portion of RPT. TEA sufficient to saturate OCT1 and OCT2 blocked only 37% of mediated amantadine transport in the S2 segment, confirming the functional presence of at least one additional OC transporter (perhaps OCT3). These data indicate that renal OC transport involves the concerted activity of a suite of transport processes.