Technetium-99m-labelled 3,3-diphosphono-1,2-propanodicarboxylic acid ((99m)Tc-DPD) is a sensitive method for imaging cardiac transthyretin (ATTR) amyloid. We report utility and limitations of ...(99m)Tc-DPD scintigraphy in 321 patients with suspected cardiac amyloidosis.
The cohort included wild-type ATTR (ATTRwt) amyloidosis in 94 (29%), ATTR-Val122Ile amyloidosis in 38 (12%), hereditary ATTR (ATTRmt) amyloidosis in 46 (14%), primary light-chain (AL) amyloidosis in 44 (14%), secondary (AA) amyloidosis in three (1%), other hereditary amyloidosis types in nine (3%), undetermined types in two (0.5%), and 85 (26.5%) patients in whom systemic amyloidosis was ultimately excluded. All 158 patients with ATTR amyloidosis with clinical cardiac involvement had cardiac (99m)Tc-DPD uptake, with median Grade 2 intensity. Thirteen further ATTR amyloidosis patients without clinical evidence of cardiac involvement also demonstrated (99m)Tc-DPD cardiac uptake. Eighteen of 35 (51%) AL patients with cardiac involvement had (99m)Tc-DPD cardiac uptake (median Grade 1 intensity). SPECT imaging indicates that the apparent reciprocal reduction in bone uptake is due to masking of bone uptake by extensive soft-tissue uptake in ATTR amyloidosis, especially ATTRwt, and ATTR-Val122Ile types.
(99m)Tc-DPD scintigraphy is a highly sensitive technique for imaging cardiac ATTR amyloidosis and is an important investigation in the diagnostic pathway of patients with cardiac amyloidosis. It is not specific for ATTR in isolation but must be interpreted in a broad clinical context to avoid dangerous diagnostic errors. Diffuse skeletal muscle uptake identifies muscle as a hitherto unrecognized site that merits investigation as a target organ in ATTR amyloidosis.
Lemborexant, a dual orexin receptor antagonist, is approved for the treatment of insomnia and is under investigation for treating other sleep disorders. Here we summarize pharmacokinetic, ...pharmacodynamic, and safety data from 3 randomized, double‐blind, placebo‐controlled phase 1 studies: single ascending doses in healthy adults (Study 001; 1‐200 mg; N = 64), multiple ascending doses in healthy and elderly adults (Study 002; 2.5‐75 mg; N = 55), and multiple doses in healthy white and Japanese adults (Study 003; 2.5‐25 mg; N = 32). Lemborexant exposure increased with increasing dose. The time to maximum concentration ranged from approximately 1 to 3 hours for the 5‐ and 10‐mg doses. The mean effective half‐life was 17 hours for lemborexant 5 mg and 19 hours for lemborexant 10 mg. The plasma concentration at 9 hours postdose was 27% of the maximum concentration following multiple dosing with lemborexant 10 mg. There were no clinically relevant effects on next‐morning residual sleepiness (Karolinska Sleepiness Scale, Digital Symbol Substitution Test, Psychomotor Vigilance Test) for doses through 10 mg/day, indicating no effect of residual plasma concentrations on next‐day residual effects. Lemborexant was well tolerated across the doses tested. There were no clinically relevant effects of age, sex, or race on lemborexant pharmacokinetics, pharmacodynamics, or safety. These results suggest that lemborexant at doses through 25 mg provides an overall pharmacokinetic, pharmacodynamic, and safety profile suitable for obtaining the target pharmacologic effect supporting treatment of insomnia while minimizing residual effects during wake time.
Bacterial blight resistance gene
has received little attention since it was first described in 1950. A near-isogenic line (NIL) of
cotton, Ac
, was generated in an otherwise ...bacterial-blight-susceptible 'Acala 44' background. The introgressed locus
in Ac
conferred strong and broad-spectrum resistance to bacterial blight. Segregation patterns of test crosses under Oklahoma field conditions indicated that Ac
is likely homozygous for resistance at two loci with partial dominance gene action. In controlled-environment conditions, two of the four copies of
were required for effective resistance. Contrary to expectations of gene-for-gene theory, Ac
conferred high resistance toward isogenic strains of
subsp.
carrying cloned avirulence genes
,
,
,
, and
, respectively, and weaker resistance toward the strain carrying cloned
. The hypothesis that each
gene, in the absence of a polygenic complex, triggers sesquiterpenoid phytoalexin production was tested by measurement of cadalene and lacinilene phytoalexins during resistant responses in five NILs carrying different
genes, four other lines carrying multiple resistance genes, as well as susceptible Ac44E. Phytoalexin production was an obvious, but variable, response in all nine resistant lines. Ac
accumulated an order of magnitude more of all four phytoalexins than any of the other resistant NILs. Its total levels were comparable to those detected in OK1.2, a highly resistant line that possesses several
genes in a polygenic background.
The survival of enteric bacteria was measured in bovine feces on pasture. In each season, 11 cow pats were prepared from a mixture of fresh dairy cattle feces and sampled for up to 150 days. Four ...pats were analyzed for Escherichia coli, fecal streptococci, and enterococci, and four inoculated pats were analyzed for Campylobacter jejuni and Salmonella enterica. Two pats were placed on drainage collectors, and another pat was fitted with a temperature probe. In the first 1 to 3 weeks, there were increases (up to 1.5 orders of magnitude) in the counts of enterococci (in four seasons), E. coli (three seasons), fecal streptococci (three seasons), and S. enterica (two seasons), but there was no increase in the counts of C. jejuni. Thereafter, the counts decreased, giving an average ranking of the times necessary for 90% inactivation of C. jejuni (6.2 days from deposition) < fecal streptococci (35 days) < S. enterica (38 days) < E. coli (48 days) < enterococci (56 days). The pat temperature probably influenced bacterial growth, but the pattern of increases and decreases was primarily determined by desiccation; growth occurred when the water content was greater than 80%, but at a water content of 70 to 75% counts decreased. E. coli and enterococcus regrowth appeared to result from pat rehydration. Of 20 monthly leaching losses of E. coli, 16 were <10% of the total counts in the pat, and 12 were <1%. Drainage losses of C. jejuni (generally <1%) were detected for only 1 to 2 months. Although enterococci exhibited the best survival rate, higher final counts suggested that E. coli is the more practical indicator of bovine fecal pollution.
Systemic lupus erythematosus (SLE) is a complex, heterogeneous autoimmune disease. A common manifestation, lupus nephritis, arises from immune complex deposition in the kidney microvasculature ...promoting leukocyte activation and infiltration, which triggers glomerular damage and renal dysfunction. CD11b is a leukocyte integrin mainly expressed on myeloid cells, and aside from its well-ascribed roles in leukocyte trafficking and phagocytosis, it can also suppress cytokine production and autoreactivity. Genome-wide association studies have identified loss-of-function polymorphisms in the CD11b-encoding gene
that are strongly associated with SLE and lupus nephritis; however, it is not known whether these polymorphisms act alone to induce disease or in concert with other risk alleles. Herein we show using
mice that loss of CD11b led to mild inflammatory traits, which were insufficient to trigger autoimmunity or glomerulonephritis. However, deficiency of CD11b in autoimmune-prone Lyn-deficient mice (
) accelerated lupus-like disease, driving early-onset immune cell dysregulation, autoantibody production and glomerulonephritis, impacting survival. Migration of leukocytes to the kidney in
mice was unhindered by lack of CD11b. Indeed, kidney inflammatory macrophages were further enriched, neutrophil retention in glomerular capillaries was increased and kidney inflammatory cytokine responses were enhanced in
mice. These findings indicate that
is a non-monogenic autoimmune susceptibility gene, with loss of functional CD11b exacerbating disease without impeding glomerular leukocyte trafficking when in conjunction with other pre-disposing genetic mutations. This highlights a primarily protective role for CD11b in restraining inflammation and autoimmune disease and provides a potential therapeutic avenue for lupus treatment.
Dysregulation of DNA methylation is an established feature of breast cancers. DNA demethylating therapies like decitabine are proposed for the treatment of triple-negative breast cancers (TNBC) and ...indicators of response need to be identified. For this purpose, we characterized the effects of decitabine in a panel of 10 breast cancer cell lines and observed a range of sensitivity to decitabine that was not subtype specific. Knockdown of potential key effectors demonstrated the requirement of deoxycytidine kinase (DCK) for decitabine response in breast cancer cells. In treatment-naïve breast tumors, DCK was higher in TNBCs, and DCK levels were sustained or increased post chemotherapy treatment. This suggests that limited DCK levels will not be a barrier to response in patients with TNBC treated with decitabine as a second-line treatment or in a clinical trial. Methylome analysis revealed that genome-wide, region-specific, tumor suppressor gene-specific methylation, and decitabine-induced demethylation did not predict response to decitabine. Gene set enrichment analysis of transcriptome data demonstrated that decitabine induced genes within apoptosis, cell cycle, stress, and immune pathways. Induced genes included those characterized by the viral mimicry response; however, knockdown of key effectors of the pathway did not affect decitabine sensitivity suggesting that breast cancer growth suppression by decitabine is independent of viral mimicry. Finally, taxol-resistant breast cancer cells expressing high levels of multidrug resistance transporter ABCB1 remained sensitive to decitabine, suggesting that the drug could be used as second-line treatment for chemoresistant patients.
The cAMP-dependent protein kinase (PKA) regulates a wide array of cellular functions. In brain and heart PKA increases the activity of the L-type Ca2+ channel Cav1.2 in response to β-adrenergic ...stimulation. Cav1.2 forms a complex with the β2-adrenergic receptor, the trimeric GS protein, adenylyl cyclase, and PKA wherein highly localized signaling occurs Davare, M. A., Avdonin, V., Hall, D. D., Peden, E. M., Burette, A., Weinberg, R. J., Horne, M. C., Hoshi, T., and Hell, J. W. (2001) Science 293, 98−101. PKA primarily phosphorylates Cav1.2 on serine 1928 of the central, pore-forming α11.2 subunit. Here we demonstrate that the A-kinase anchor protein 150 (AKAP150) is critical for PKA-mediated regulation of Cav1.2 in the brain. AKAP150 and MAP2B specifically co-immunoprecipitate with Cav1.2 from rat brain. Recombinant AKAP75, the bovine homologue to rat AKAP150, binds directly to three different sites of α11.2. MAP2B from rat brain also interacts with these same sites in pull-down assays. Gene disruption of AKAP150 in mice dramatically reduces co-immunoprecipitation of PKA with Cav1.2 and prevents phosphorylation of serine 1928 upon β-adrenergic stimulation in vivo. These results demonstrate the physiological relevance of PKA anchoring by AKAPs in general and AKAP150 specifically in the regulation of Cav1.2 in vivo.
Individuals living with chronic advanced cancer (CAC) often face distinct physical, functional, and cognitive issues. Their rehabilitation needs are not yet routinely met, warranting further ...CAC-specific rehabilitation-based research. Given the complexity of functional and symptom presentations, engagement of individuals living with CAC as partners in the research process is encouraged to better understand the lived perspective. Formal engagement requires both structured approaches and iterative processes. The aim was to co-design a conceptual framework to develop and integrate engagement strategies into rehabilitation research focused on CAC populations.
A multidisciplinary team of authors, including two individuals with lived experience, conducted an implementation-focused descriptive study to inform future research design, including: interviews and follow-up, review of current models and approaches, and development of a co-designed conceptual framework for engaging individuals with lived experience into CAC-specific rehabilitation research.
Emergent themes include shared understanding, transparent appreciation, iterative processes and unique partnership needs. A definition, guiding principles and tools for engagement were identified. In consultation with individuals with lived experience, and application of the emergent themes in context, a conceptual framework to guide the engagement process was developed.
A novel conceptual framework for engaging individuals with lived experience with CAC as partners in rehabilitation research is proposed to facilitate implementation-focused team-based approaches for this population.
A dynamic actin cytoskeleton is necessary for viral entry, intracellular migration, and virion release. For HIV-1 infection, during entry, the virus triggers early actin activity by hijacking ...chemokine coreceptor signaling, which activates a host dependency factor, cofilin, and its kinase, the LIM domain kinase (LIMK). Although knockdown of human LIM domain kinase 1 (LIMK1) with short hairpin RNA (shRNA) inhibits HIV infection, no specific small-molecule inhibitor of LIMK has been available. Here, we describe the design and discovery of novel classes of small-molecule inhibitors of LIMK for inhibiting HIV infection. We identified R10015 as a lead compound that blocks LIMK activity by binding to the ATP-binding pocket. R10015 specifically blocks viral DNA synthesis, nuclear migration, and virion release. In addition, R10015 inhibits multiple viruses, including Zaire ebolavirus (EBOV), Rift Valley fever virus (RVFV), Venezuelan equine encephalitis virus (VEEV), and herpes simplex virus 1 (HSV-1), suggesting that LIMK inhibitors could be developed as a new class of broad-spectrum antiviral drugs.
The actin cytoskeleton is a structure that gives the cell shape and the ability to migrate. Viruses frequently rely on actin dynamics for entry and intracellular migration. In cells, actin dynamics are regulated by kinases, such as the LIM domain kinase (LIMK), which regulates actin activity through phosphorylation of cofilin, an actin-depolymerizing factor. Recent studies have found that LIMK/cofilin are targeted by viruses such as HIV-1 for propelling viral intracellular migration. Although inhibiting LIMK1 expression blocks HIV-1 infection, no highly specific LIMK inhibitor is available. This study describes the design, medicinal synthesis, and discovery of small-molecule LIMK inhibitors for blocking HIV-1 and several other viruses and emphasizes the feasibility of developing LIMK inhibitors as broad-spectrum antiviral drugs.
Lower extremity amputation is common among patients with ESRD, and often portends a poor prognosis. However, little is known about end-of-life care among patients with ESRD who undergo amputation.
We ...conducted a mortality follow-back study of Medicare beneficiaries with ESRD who died in 2002 through 2014 to analyze patterns of lower extremity amputation in the last year of life compared with a parallel cohort of beneficiaries without ESRD. We also examined the relationship between amputation and end-of-life care among the patients with ESRD.
Overall, 8% of 754,777 beneficiaries with ESRD underwent at least one lower extremity amputation in their last year of life compared with 1% of 958,412 beneficiaries without ESRD. Adjusted analyses of patients with ESRD showed that those who had undergone lower extremity amputation were substantially more likely than those who had not to have been admitted to-and to have had prolonged stays in-acute and subacute care settings during their final year of life. Amputation was also associated with a greater likelihood of dying in the hospital, dialysis discontinuation before death, and less time receiving hospice services.
Nearly one in ten patients with ESRD undergoes lower extremity amputation in their last year of life. These patients have prolonged stays in acute and subacute health care settings and appear to have limited access to hospice services. These findings likely signal unmet palliative care needs among seriously ill patients with ESRD who undergo amputation as well as opportunities to improve their care.
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