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Multiple myeloma (MM) is a blood cancer caused by uncontrolled growth of clonal plasmacells. Bone disease is responsible for the severe complications of MM and is caused by myeloma cells infiltrating the bone marrow and inducing osteoclast activation. To date, no treatment for MM is truly curative since patients relapse and become refractory to all drug classes. Cannabinoids are already used as palliative in cancer patients. Furthermore, their proper anticancer effect was demonstrated in many cancer models in vitro, in vivo, and in clinical trials. Anyway, few information was reported on the effect of cannabinoids on MM and no data has been provided on minor phytocannabinoids such as cannabigerol (CBG), cannabichromene (CBC), cannabinol (CBN), and cannabidivarin (CBDV). Scientific literature also reported cannabinoids beneficial effect against bone disease. Here, we examined the cytotoxic activity of CBG, CBC, CBN, and CBDV in vitro in MM cell lines, their effect in modulating MM cells invasion toward bone cells and the bone resorption. Subsequently, according to the in vitro results, we selected CBN for in vivo study in a MM xenograft mice model. Results showed that the phytocannabinoids inhibited MM cell growth and induced necrotic cell death. Moreover, the phytocannabinoids reduced the invasion of MM cells toward osteoblast cells and bone resorption in vitro. Lastly, CBN reduced in vivo tumor mass. Together, our results suggest that CBG, CBC, CBN, and CBDV can be promising anticancer agents for MM. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) has poor prognosis and high mortality rates. Therefore, it is necessary to identify new targets and therapeutic strategies to improve the prognosis of patients with PDAC. Integrative therapies are increasingly being used to boost the efficacy of the known anticancer therapeutic approaches. Hence, this study aimed to evaluate the effects of a novel combination of different potential anticancer molecules, melatonin (MLT), cannabidiol (CBD), and oxygen–ozone (O2/O3) to treat PDAC using in vitro and in vivo models of human PDAC. The effect of this combination was investigated in combination with gemcitabine (GEM), the most common chemotherapeutic drug used for PDAC treatment. The combination of MLT + CBD + O2/O3 was more effective than the individual treatments in inhibiting PDAC cell viability and proliferation, inducing cell death, and modulating the RAS pathway protein levels. Moreover, different combinations of treatments reduced tumor mass in the PDAC mouse model, thus promoting the effect of GEM. In conclusion, a mixture of MLT + CBD + O2/O3 could serve as a potential adjuvant therapeutic strategy for PDAC. [ABSTRACT FROM AUTHOR]

The larvae of many marine species are pelagic drifters in the vast oceans, yet they are the first and, for sessile species, the only way to connect with other populations. Connectivity is of particular interest in designing and assessing marine protected areas (MPAs), as it is considered a factor of renewal and stability.In this study, we focused on larval mixing between MPAs, investigating mixing rates during and at the end of their pelagic life, and how this is affected by the timing of larval release. We used a particle transport model coupled to the climatological hydrodynamics of the northwestern Mediterranean Sea to simulate the trajectories of Nephrops norvegicus larvae. Larvae were released from four no‐take MPAs, where fishery activity is banned, and started mixing between 7 and 12 days old.At settlement time, larval mixing mainly occurred between two pairs of MPAs labelled AxB (49.4% ± 5.8%) and CxD (23.7% ± 10.7%), respectively, located on the northern and southern sides of a thermal front. Percentages of larval mixing between these pairs changed, and other MPA combinations were formed with delayed larval release times. Mixing of larvae released from the same MPA tended to decrease with increasing delays between release times.This variability in mixing was related to the latitudinal distribution of MPAs along the continental slope and the spatiotemporal dynamics of the regional hydrodynamics, with a strong impact from a thermal front.Larval mixing modelling is a useful measure for understanding connectivity in marine environments and can suggest new conservation decisions. It identifies MPAs that are spatially distributed to facilitate the convergence of larvae from various protected areas. It also underlines that recognizing the significance of hydrodynamic variability when designing MPAs is crucial for promoting efficient connectivity among these areas. [ABSTRACT FROM AUTHOR]

Lophelia pertusa reefs are vulnerable deep‐sea ecosystems and their ecological integrity partly depends on the connectivity and availability of suitable habitat. Moreover, connectivity is a guiding principle in marine conservation planning, particularly for spatial prioritization and for the design of networks of marine protected areas. We estimated the functional seascape connectivity of L. pertusa in the Mediterranean Sea and provide a framework for prioritizing habitat areas for the species conservation. These goals were achieved by simulating transport and potential dispersal of virtual larvae using biophysical modeling and assessing habitat availability based on the suitability and spatial arrangement of the seascape and inter‐annual climatological variability. Habitat availability was estimated using a network analysis and accounting for the attributes of habitat areas (i.e., size and quality). The connectivity among Mediterranean ecoregions was weak and an increase in the frequency of climate‐driven events (e.g., dense shelf water cascading) may worsen this scenario. However, the potential exchange of larvae between patches within the same ecoregion was high, favoring populations resilience to local disturbances. The analysis of habitat availability allowed identifying important habitat areas for the connectivity of the L. pertusa including the Gulf of Lion, the Apulian and Sicily Island continental margin. Some of the habitat areas identified as important for the connectivity of the L. pertusa are exposed to intense anthropogenic pressures, that may act synergistically with climate change imposing greater challenges to species conservation. These habitat areas may be prioritized in future management and conservation actions targeting L. pertusa. [ABSTRACT FROM AUTHOR]

The cellular prion protein PrPC mediates the neurotoxicity of prions and other protein aggregates through poorly understood mechanisms. Antibody‐derived ligands against the globular domain of PrPC (GDL) can also initiate neurotoxicity by inducing an intramolecular R208‐H140 hydrogen bond ("H‐latch") between the α2‐α3 and β2‐α2 loops of PrPC. Importantly, GDL that suppresses the H‐latch prolong the life of prion‐infected mice, suggesting that GDL toxicity and prion infections exploit convergent pathways. To define the structural underpinnings of these phenomena, we transduced 19 individual PrPC variants to PrPC‐deficient cerebellar organotypic cultured slices using adenovirus‐associated viral vectors (AAV). We report that GDL toxicity requires a single N‐proximal cationic residue (K27 or R27) within PrPC. Alanine substitution of K27 also prevented the toxicity of PrPC mutants that induce Shmerling syndrome, a neurodegenerative disease that is suppressed by co‐expression of wild‐type PrPC. K27 may represent an actionable target for compounds aimed at preventing prion‐related neurodegeneration. [ABSTRACT FROM AUTHOR]

Many efforts targeting amyloid‐β (Aβ) plaques for the treatment of Alzheimer's Disease thus far have resulted in failures during clinical trials. Regional and temporal heterogeneity of efficacy and dependence on plaque maturity may have contributed to these disappointing outcomes. In this study, we mapped the regional and temporal specificity of various anti‐Aβ treatments through high‐resolution light‐sheet imaging of electrophoretically cleared brains. We assessed the effect on amyloid plaque formation and growth in Thy1‐APP/PS1 mice subjected to β‐secretase inhibitors, polythiophenes, or anti‐Aβ antibodies. Each treatment showed unique spatiotemporal Aβ clearance, with polythiophenes emerging as a potent anti‐Aβ compound. Furthermore, aligning with a spatial‐transcriptomic atlas revealed transcripts that correlate with the efficacy of each Aβ therapy. As observed in this study, there is a striking dependence of specific treatments on the location and maturity of Aβ plaques. This may also contribute to the clinical trial failures of Aβ‐therapies, suggesting that combinatorial regimens may be significantly more effective in clearing amyloid deposition. Synopsis: The brain is highly compartmentalized with many distinct regions. It is unknown how drugs for treating Alzheimer's Disease (AD) work across brain regions and disease stages. We developed a technology to quantify the effects of different AD drugs throughout the brain at different time points. A novel technology was developed for high‐throughput optical mouse brain clarification and staining of Aβ plaques, followed by lightsheet imaging, brain atlas registration, and plaque morphology quantification.Mice were treated with either a BACE1 inhibitor, a polythiophene for stabilizing amyloid fibrils, or an anti‐Aβ antibody.Quantitative results show distinct Aβ plaque modification and removal across brain regions and disease stage.Spatial efficacy profiles of anti‐Aβ therapies were correlated with gene expression maps using a spatial transcriptomics brain atlas. [ABSTRACT FROM AUTHOR]

A defining characteristic of mammalian prions is their capacity for self‐sustained propagation. Theoretical considerations and experimental evidence suggest that prion propagation is modulated by cell‐autonomous and non‐autonomous modifiers. Using a novel quantitative phospholipase protection assay (QUIPPER) for high‐throughput prion measurements, we performed an arrayed genome‐wide RNA interference (RNAi) screen aimed at detecting cellular host‐factors that can modify prion propagation. We exposed prion‐infected cells in high‐density microplates to 35,364 ternary pools of 52,746 siRNAs targeting 17,582 genes representing the majority of the mouse protein‐coding transcriptome. We identified 1,191 modulators of prion propagation. While 1,151 modified the expression of both the pathological prion protein, PrPSc, and its cellular counterpart, PrPC, 40 genes selectively affected PrPSc. Of the latter 40 genes, 20 augmented prion production when suppressed. A prominent limiter of prion propagation was the heterogeneous nuclear ribonucleoprotein Hnrnpk. Psammaplysene A (PSA), which binds Hnrnpk, reduced prion levels in cultured cells and protected them from cytotoxicity. PSA also reduced prion levels in infected cerebellar organotypic slices and alleviated locomotor deficits in prion‐infected Drosophila melanogaster expressing ovine PrPC. Hence, genome‐wide QUIPPER‐based perturbations can discover actionable cellular pathways involved in prion propagation. Further, the unexpected identification of a prion‐controlling ribonucleoprotein suggests a role for RNA in the generation of infectious prions. Synopsis: A systematic analysis for cellular host‐factors involved in prion propagation has been missing due to the lack of a compatible high‐throughput detection method. This study describes the development and application of a novel prion detection assay and identifies new host‐factors involved in prion propagation. The QUantItative Prion PhospholipasE pRotection assay (QUIPPER) allows for prion detection in cultured cells in a high‐throughput format.A genome‐wide screen in prion infected mouse cells identifies new host factors for prion propagation.Hnrnpk/HNRNPK limits prion formation in mouse and human cells.The compound Psammaplysene A can reduce prion formation in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Background: Multiple System Atrophy is a rare neurodegenerative disease with alpha-synuclein aggregation in glial cytoplasmic inclusions and either predominant olivopontocerebellar atrophy or striatonigral degeneration, leading to dysautonomia, parkinsonism, and cerebellar ataxia. One prior genome-wide association study in mainly clinically diagnosed patients with Multiple System Atrophy failed to identify genetic variants predisposing for the disease.Objective: Since the clinical diagnosis of Multiple System Atrophy yields a high rate of misdiagnosis when compared to the neuropathological gold standard, we studied only autopsy-confirmed cases.Methods: We studied common genetic variations in Multiple System Atrophy cases (N = 731) and controls (N = 2898).Results: The most strongly disease-associated markers were rs16859966 on chromosome 3, rs7013955 on chromosome 8, and rs116607983 on chromosome 4 with P-values below 5 × 10-6 , all of which were supported by at least one additional genotyped and several imputed single nucleotide polymorphisms. The genes closest to the chromosome 3 locus are ZIC1 and ZIC4 encoding the zinc finger proteins of cerebellum 1 and 4 (ZIC1 and ZIC4).Interpretation: Since mutations of ZIC1 and ZIC4 and paraneoplastic autoantibodies directed against ZIC4 are associated with severe cerebellar dysfunction, we conducted immunohistochemical analyses in brain tissue of the frontal cortex and the cerebellum from 24 Multiple System Atrophy patients. Strong immunohistochemical expression of ZIC4 was detected in a subset of neurons of the dentate nucleus in all healthy controls and in patients with striatonigral degeneration, whereas ZIC4-immunoreactive neurons were significantly reduced inpatients with olivopontocerebellar atrophy. These findings point to a potential ZIC4-mediated vulnerability of neurons in Multiple System Atrophy. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Although prion infections cause cognitive impairment and neuronal death, transcriptional and translational profiling shows progressive derangement within glia but surprisingly little changes within neurons. Here we expressed PrPC selectively in neurons and astrocytes of mice. After prion infection, both astrocyte and neuron‐restricted PrPC expression led to copious brain accumulation of PrPSc. As expected, neuron‐restricted expression was associated with typical prion disease. However, mice with astrocyte‐restricted PrPC expression experienced a normal life span, did not develop clinical disease, and did not show astro‐ or microgliosis. Besides confirming that PrPSc is innocuous to PrPC‐deficient neurons, these results show that astrocyte‐born PrPSc does not activate the extreme neuroinflammation that accompanies the onset of prion disease and precedes any molecular changes of neurons. This points to a nonautonomous mechanism by which prion‐infected neurons instruct astrocytes and microglia to acquire a specific cellular state that, in turn, drives neural dysfunction. [ABSTRACT FROM AUTHOR]

Background and purpose: Cerebrospinal fluid (CSF) real‐time quaking‐induced conversion (RT‐QuIC) has a high degree of sensitivity and specificity for the diagnosis of sporadic Creutzfeldt–Jakob disease (sCJD) and this has led to its being included in revised European CJD Surveillance Network diagnostic criteria for sCJD. As CSF RT‐QuIC becomes more widely established, it is crucial that the analytical performance of individual laboratories is consistent. The aim of this ring‐trial was to ascertain the degree of concordance between European countries undertaking CSF RT‐QuIC. Methods: Ten identical CSF samples, seven from probable or neuropathologically confirmed sCJD and three from non‐CJD cases, were sent to 13 laboratories from 11 countries for RT‐QuIC analysis. A range of instrumentation and different recombinant prion protein substrates were used. Each laboratory analysed the CSF samples blinded to the diagnosis and reported the results as positive or negative. Results: All 13 laboratories correctly identified five of the seven sCJD cases and the remaining two sCJD cases were identified by 92% of laboratories. Of the two sCJD cases that were not identified by all laboratories, one had a disease duration >26 months with a negative 14‐3‐3, whilst the remaining case had a 4‐month disease duration and a positive 14‐3‐3. A single false positive CSF RT‐QuIC result was observed in this study. Conclusions: This study shows that CSF RT‐QuIC demonstrates an excellent concordance between centres, even when using a variety of instrumentation, recombinant prion protein substrates and CSF volumes. The adoption of CSF RT‐QuIC by all CJD surveillance centres is recommended. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by accumulation of immature cells in bone marrow and peripheral blood. Although successful results were obtained with tyrosine kinase inhibitors, several patients showed resistance. For this reason, the identification of new strategies and therapeutic biomarkers represents an attractive goal. The role of transient receptor potential (TRP) ion channels as possible drug targets has been elucidated in different types of cancer. Among natural compounds known to activate TRPs, cannabidiol (CBD) displays anticancer properties. By using FACS analysis, confocal microscopy, gene silencing, and cell growth assay, we demonstrated that CBD, through TRPV2, inhibits cell proliferation and cell cycle in CML cells. It promoted mitochondria dysfunction and mitophagy as shown by mitochondrial mass reduction and up‐regulation of several mitophagy markers. These effects were associated with changes in the expression of octamer‐binding transcription factor 4 and PU.1 markers regulated during cellular differentiation. Interestingly, a synergistic effect by combining CBD with the standard drug imatinib was found and imatinib‐resistant cells remain susceptible to CBD effects. Therefore, the targeting of TRPV2 by using CBD, through the activation of mitophagy and the reduction in stemness, could be a promising strategy to enhance conventional therapy and improve the prognosis of CML patients. [ABSTRACT FROM AUTHOR]

Brain‐matter vacuolation is a defining trait of all prion diseases, yet its cause is unknown. Here, we report that prion infection and prion‐mimetic antibodies deplete the phosphoinositide kinase PIKfyve—which controls endolysosomal maturation—from mouse brains, cultured cells, organotypic brain slices, and brains of Creutzfeldt‐Jakob disease victims. We found that PIKfyve is acylated by the acyltransferases zDHHC9 and zDHHC21, whose juxtavesicular topology is disturbed by prion infection, resulting in PIKfyve deacylation and rapid degradation, as well as endolysosomal hypertrophy and activation of TFEB‐dependent lysosomal enzymes. A protracted unfolded protein response (UPR), typical of prion diseases, also induced PIKfyve deacylation and degradation. Conversely, UPR antagonists restored PIKfyve levels in prion‐infected cells. Overexpression of zDHHC9 and zDHHC21, administration of the antiprion polythiophene LIN5044, or supplementation with the PIKfyve reaction product PI(3,5)P2 suppressed prion‐induced vacuolation and restored lysosomal homeostasis. Thus, PIKfyve emerges as a central mediator of vacuolation and neurotoxicity in prion diseases. Synopsis: The phosphoinositide kinase PIKfyve is identified as the driver of brain vacuolation (spongiosis) in prion diseases. A hierarchy of events, starting the delocalization of PIKfyve‐specific acyltransferases and culminating in the enlargement of endolysosomes underlying spongiosis, is established. The kinase PIKfyve converts phosphoinositol‐3‐phosphate into PI(3,5)‐diphosphate.PIKfyve is physiologically acylated by the acyltransferases zDHHC9 and zDHHC21.Prion infection induces PIKfyve deacylation, thereby reducing its half‐life and depleting it from infected cells.PIKfyve depletion results in spongiosis and lysosomal defects.Prion‐induced spongiosis can be rescued by PI(3,5) analogues or by overexpressing zDHHC9/21. [ABSTRACT FROM AUTHOR]

To evaluate the role of bosutinib in elderly patients aged >65 years with chronic myeloid leukemia (CML), a real‐life cohort of 101 chronic‐phase CML patients followed up in 23 Italian centers and treated with bosutinib in second or a subsequent line was retrospectively evaluated. Starting dose of bosutinib was 500 mg/day in 25 patients (24.8%), 400 mg/day in 7 patients (6.9%), 300 mg/day in 33 patients (32.7%), 200 mg/day in 34 patients (33.6%), and 100 mg/day in 2 patients (2.0%). Grade 3/4 hematological toxicity occurred in 7/101 patients (6.9%) and grade 3/4 extra‐hematological toxicity in 19/101 patients (18.8%). Permanent bosutinib discontinuation due to toxicity was needed in 12 patients (11.9%). Among the 96 patients evaluable for response, 74 (77.0%) achieved a complete cytogenetic response (CCyR), while 64 of these 74 patients in CCyR (66.6% of all 96 evaluable patients) also achieved a molecular response (MR) (major MR [MR 3.0] in 21 [21.8%], deep MR [MR 4.0/4.5] in 43 [44.8%]). The 3‐year event‐free survival and overall survival of the whole patients' cohort from bosutinib start were 60.9% (CI 95% 49.3–72.5) and 86.4% (CI 95% 77.2–95.6), respectively. Our real‐life data show that bosutinib is effective, with a favorable safety profile, also in elderly patients with important comorbidities and resistance and/or intolerance to previous tyrosine‐kinase inhibitor treatments. As a consequence, it could play a significant role in current clinical practice for frail patients. [ABSTRACT FROM AUTHOR]

Coronavirus disease 19 (COVID‐19) is a rapidly evolving pandemic caused by the coronavirus Sars‐CoV‐2. Clinically manifest central nervous system symptoms have been described in COVID‐19 patients and could be the consequence of commonly associated vascular pathology, but the detailed neuropathological sequelae remain largely unknown. A total of six cases, all positive for Sars‐CoV‐2, showed evidence of cerebral petechial hemorrhages and microthrombi at autopsy. Two out of six patients showed an elevated risk for disseminated intravascular coagulopathy according to current criteria and were excluded from further analysis. In the remaining four patients, the hemorrhages were most prominent at the grey and white matter junction of the neocortex, but were also found in the brainstem, deep grey matter structures and cerebellum. Two patients showed vascular intramural inflammatory infiltrates, consistent with Sars‐CoV‐2‐associated endotheliitis, which was associated by elevated levels of the Sars‐CoV‐2 receptor ACE2 in the brain vasculature. Distribution and morphology of patchy brain microbleeds was clearly distinct from hypertension‐related hemorrhage, critical illness‐associated microbleeds and cerebral amyloid angiopathy, which was ruled out by immunohistochemistry. Cerebral microhemorrhages in COVID‐19 patients could be a consequence of Sars‐ CoV‐2‐induced endotheliitis and more general vasculopathic changes and may correlate with an increased risk of vascular encephalopathy. [ABSTRACT FROM AUTHOR]

Tauopathies are prevalent, invariably fatal brain diseases for which no cure is available. Tauopathies progressively affect the brain through cell‐to‐cell transfer of tau protein amyloids, yet the spreading mechanisms remain unknown. Here we show that the cellular prion protein (PrPC) facilitates the uptake of tau aggregates by cultured cells, possibly by acting as an endocytic receptor. In mouse neuroblastoma cells, pull‐down experiments revealed that tau amyloids bind to PrPC. Confocal images of both wild‐type and PrPC ‐knockout N2a cells treated with fluorescently labeled synthetic tau fibrils showed that the internalization was reduced in isogenic cells devoid of the gene encoding PrPC. Pre‐treatment of the same cells with antibodies against N‐proximal epitopes of PrPC impaired the binding of tau amyloids and decreased their uptake. Surprisingly, exposure of chronically prion‐infected cells to tau amyloids reduced the accumulation of aggregated prion protein and this effect lasted for more than 72 hr after amyloid removal. These results point to bidirectional interactions between the two proteins: while PrPC mediates the entrance of tau fibrils in cells, PrPSc buildup is greatly reduced in their presence, possibly because of an impairment in the prion conversion process. [ABSTRACT FROM AUTHOR]

Ravulizumab, a novel long‐acting complement component 5 (C5) inhibitor administered every 8 weeks (q8w), was non‐inferior to eculizumab for all efficacy outcomes in two randomised, open‐label, phase 3 trials in C5 inhibitor‐naïve (Study 301) and eculizumab‐experienced (Study 302) adult patients with paroxysmal nocturnal haemoglobinuria (PNH). This pre‐specified analysis characterised ravulizumab pharmacokinetics (PK), pharmacodynamics (PD; free C5 levels), and PD differences between medications (Study 301, n = 246; Study 302, n = 195). Ravulizumab PK parameters were determined using non‐compartmental analysis. Serum free C5 was quantified with a Gyros‐based fluorescence assay (ravulizumab) and an electrochemiluminescence ligand‐binding assay (eculizumab). Ravulizumab PK parameters were numerically comparable in both studies; the median time to maximum concentrations ranged from 2·3 to 2·8 and 2·3 to 2·6 h in studies 301 and 302, respectively. Ravulizumab steady‐state serum concentrations were achieved immediately after the first dose and sustained throughout treatment. For ravulizumab, the mean (SD) post hoc terminal elimination half‐life was 49·7 (8·9) days. Serum free C5 concentrations <0·5 µg/ml were achieved after the first ravulizumab dose and sustained throughout treatment in both studies. In a minority of patients, free C5 concentrations <0·5 µg/ml were not consistently achieved with eculizumab in either study. Ravulizumab q8w was more consistent in providing immediate, complete, sustained C5 inhibition than eculizumab every‐2‐weeks in patients with PNH. [ABSTRACT FROM AUTHOR]

Prion immunotherapy may hold great potential, but antibodies against certain PrP epitopes can be neurotoxic. Here, we identified > 6,000 PrP‐binding antibodies in a synthetic human Fab phage display library, 49 of which we characterized in detail. Antibodies directed against the flexible tail of PrP conferred neuroprotection against infectious prions. We then mined published repertoires of circulating B cells from healthy humans and found antibodies similar to the protective phage‐derived antibodies. When expressed recombinantly, these antibodies exhibited anti‐PrP reactivity. Furthermore, we surveyed 48,718 samples from 37,894 hospital patients for the presence of anti‐PrP IgGs and found 21 high‐titer individuals. The clinical files of these individuals did not reveal any enrichment of specific pathologies, suggesting that anti‐PrP autoimmunity is innocuous. The existence of anti‐prion antibodies in unbiased human immunological repertoires suggests that they might clear nascent prions early in life. Combined with the reported lack of such antibodies in carriers of disease‐associated PRNP mutations, this suggests a link to the low incidence of spontaneous prion diseases in human populations. Synopsis: This study assessed the anti‐prion protein (PrP) immunoreactivity in human immunoglobulin repertoires and patient samples. Anti‐PrP autoimmunity can exist in human communities, appears to be innocuous, and may protect against prion infections. >6,000 antibodies against various PrP epitopes were recovered from a synthetic human antibody (Fab) phage library.Of the phage display derived Fabs, 49 Fabs were characterized in detail. Fabs directed against the N‐terminal flexible tail of PrP conferred neuroprotection against infectious prions.HCDR3 sequences similar to a protective phage‐derived Fab were identified in published repertoires of B cells from healthy humans. When expressed recombinantly, these antibodies reacted to human PrP.By interrogating a large cohort of 37,894 hospital patients, twenty‐one individuals with high‐titer anti‐PrP autoreactivity in the plasma were found.The presence of anti‐PrP autoantibodies did not correlate to any neurological condition or any other diseases. [ABSTRACT FROM AUTHOR]

Background: Role of erythropoietin (EPO) in the treatment of late anemia in patients with Chronic Myeloid Leukemia (CML) is still undefined. Methods: Fifty CML patients treated at 14 institutions with frontline imatinib for at least 12 months and in stable complete cytogenetic response who developed a late chronic anemia treated with EPO were retrospectively evaluated. Results: Median time from imatinib start to EPO treatment was 42.2 months [interquartile range (IQR) 20.8‐91.9]. Median Hb value at EPO starting time was 9.9 g/dL (IQR 8.9‐10.3): Eleven patients (22.0%) were transfusion dependent. Alpha‐EPO (40 000 UI weekly) was employed in 37 patients, beta‐EPO (30 000 UI weekly) in 9 patients, zeta‐EPO (40 000 UI weekly) in 2 patients, and darbepoetin (150 mcg/weekly) in the remaining 2 patients. On the whole, 41 patients (82.0%) achieved an erythroid response, defined as a stable (>3 months) improvement >1.5 g/dL of Hb level, and 9 patients (18.0%) indeed resulted resistant. Among responding patients, 10 relapsed after a median time from EPO start of 20.7 months (IQR 10.8‐63.7). No EPO‐related toxicity was observed. Conclusions: Results of EPO treatment for late chronic anemia during long‐lasting imatinib therapy are encouraging, with a high rate of response. [ABSTRACT FROM AUTHOR]

Prion diseases in mammals are caused by a conformational transition of the cellular prion protein from its native conformation (PrPC) to a pathological isoform called "prion protein scrapie" (PrPSc). A molecular level of understanding of this conformational transition will be helpful in unveiling the disease etiology. Experimental structural biological techniques (NMR and X‐ray crystallography) have been used to unravel the atomic level structural information for the prion and its binding partners. More than one hundred three‐dimensional structures of the mammalian prions have been deposited in the protein databank. Structural studies on the prion protein and its structural transitions will deepen our understanding of the molecular basis of prion pathogenesis and will provide valuable guidance for future structure‐based drug discovery endeavors. [ABSTRACT FROM AUTHOR]

Halloysite nanotubes (HLNTs) were used as nanocarriers of the tuberculostatic agent isoniazid (INH), a BCS (Biopharmaceutics Classification System) class III drug. Self‐assembling nanohybrids (INH‐loaded HLNTs) with an average outer diameter of 90 nm and polydispersity index of 0.7 approximately, were obtained by spontaneous adsorption of INH molecules to HLNTs powder in aqueous medium. The nanohybrids were aimed to improve oral drug bioavailability and reduce physicochemical incompatibility of INH with other concomitantly administered tuberculostatic agents. In vitro drug release from INH‐loaded HLNTs was successfully fitted to a diffusive kinetic law founded on the adsorption–desorption equilibrium between drug molecules in solution and solid inorganic excipients. INH‐loaded HLNTs showed good in vitro biocompatibility toward Caco‐2 cells at the concentrations studied (up to 1233 μg/mL), with improved cell proliferation. Permeability tests showed that INH transport across Caco‐2 cellular membranes was greatly enhanced and fluorescent microscopy confirmed that the drug encapsulated into nanohybrid was effectively internalized by the cells. INH‐loaded HLNTs enhanced stability of the drug in presence of other tuberculostatic agents, both in binary and quaternary combinations. It has been demonstrated that simple interaction between INH with HLNTs leads to drug permeability and stability improvements that could greatly facilitate the design of multiple drug dosage forms, an actual challenge in oral treatment of tuberculosis. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019. [ABSTRACT FROM AUTHOR]

The cellular prion protein (PrPC) is best known for its misfolded disease‐causing conformer, PrPSc. Because the availability of PrPC is often limiting for prion propagation, understanding its regulation may point to possible therapeutic targets. We sought to determine to what extent the human microRNAome is involved in modulating PrPC levels through direct or indirect pathways. We probed PrPC protein levels in cells subjected to a genome‐wide library encompassing 2019 miRNA mimics using a robust time‐resolved fluorescence‐resonance screening assay. Screening was performed in three human neuroectodermal cell lines: U‐251 MG, CHP‐212 and SH‐SY5Y. The three screens yielded 17 overlapping high‐confidence miRNA mimic hits, 13 of which were found to regulate PrPC biosynthesis directly via binding to the PRNP 3'UTR, thereby inducing transcript degradation. The four remaining hits (miR‐124‐3p, 192‐3p, 299‐5p and 376b‐3p) did not bind either the 3'UTR or CDS of PRNP, and were therefore deemed indirect regulators of PrPC. Our results show that multiple miRNAs regulate PrPC levels both directly and indirectly. These findings may have profound implications for prion disease pathogenesis and potentially also for their therapy. Furthermore, the possible role of PrPC as a mediator of Aβ toxicity suggests that its regulation by miRNAs may also impinge on Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Abstract: On/into/through the skin drug delivery represents an attractive alternative for the oral route, providing local and/or systemic drug delivery. Due to its complex and well‐organised structure, most of the drugs show difficulties to penetrate the human skin. Therefore, enormous efforts have been invested to develop intelligent drug delivery systems overcoming the skin barrier with particular emphasis on increasing therapeutic activity and minimizing undesirable side‐effects. Most of these strategies require the use of singular materials with new properties. In particular, and on the basis of their inherent properties, including biocompatibility, biodegradability and relative low‐cost, inorganic nanoparticles are ideal candidates for the development of skin drug delivery systems. This review provides an updated and comprehensive overview of the state of the art in the trends towards skin drug delivery with a particular focus in the attractive alternative offered by inorganic‐based nanosystems. [ABSTRACT FROM AUTHOR]

Conversion of the cellular prion protein PrPC into its pathogenic isoform PrPSc is the hallmark of prion diseases, fatal neurodegenerative diseases affecting many mammalian species including humans. Anti‐prion monoclonal antibodies can arrest the progression of prion diseases by stabilizing the cellular form of the prion protein. Here, we present the crystal structure of the POM6 Fab fragment, in complex with the mouse prion protein (moPrP). The prion epitope of POM6 is in close proximity to the epitope recognized by the purportedly toxic antibody fragment, POM1 Fab also complexed with moPrP. The POM6 Fab recognizes a larger binding interface indicating a likely stronger binding compared to POM1. POM6 and POM1 exhibit distinct biological responses. Structural comparisons of the bound mouse prion proteins from the POM6 Fab:moPrP and POM1 Fab:moPrP complexes reveal several key regions of the prion protein that might be involved in initiating mis‐folding events. Database: The structural data of moPrP:POM6 Fab complex are available in the PDB under the accession number www.rcsb.org/pdb/search/structidSearch.do?structureId=6AQ7. [ABSTRACT FROM AUTHOR]

Recent technological development has increased our capacity to study the deep sea and the marine benthic realm, particularly with the development of multidisciplinary seafloor observatories. Since 2006, Ocean Networks Canada cabled observatories, have acquired nearly 65 TB and over 90 000 h of video data from seafloor cameras and remotely operated vehicles. Manual processing of these data is time-consuming and highly labour-intensive, and cannot be comprehensively undertaken by individual researchers. These videos are a crucial source of information for assessing natural variability and ecosystem responses to increasing human activity in the deep sea., We compared the performance of three groups of humans and one computer vision algorithm in counting individuals of the commercially important sablefish (or black cod) Anoplopoma fimbria, in recorded video from a cabled camera platform at 900 m depth in a submarine canyon in the Northeast Pacific. The first group of human observers were untrained volunteers recruited via a crowdsourcing platform and the second were experienced university students, who performed the task for their ichthyology class. Results were validated against counts obtained from a scientific expert., All groups produced relatively accurate results in comparison to the expert and all succeeded in detecting patterns and periodicities in fish abundance data. Trained volunteers displayed the highest accuracy and the algorithm the lowest., As seafloor observatories increase in number around the world, this study demonstrates the value of a hybrid combination of crowdsourcing and computer vision techniques as a tool to help process large volumes of imagery to support basic research and environmental monitoring. Reciprocally, by engaging large numbers of online participants in deep-sea research, this approach can contribute significantly to ocean literacy and informed citizen input to policy development. [ABSTRACT FROM AUTHOR]

To characterize the development of tissue damage following cryogenic injury to the mouse cortex, the time course of histopathological changes, transcriptional responses and DNA strand breaks following application of a liquid nitrogen-cooled probe to the surface of the parietal bone were assessed. Distinct phases of tissue damage were observed: after 30 min, there was demarcation of a core lesion followed by mainly necrotic cell death starting 2 h after injury. At 12 hours, progressive apoptotic death of scattered cells in the periphery of the core lesion was detected, resembling the penumbra observed in ischaemic stroke. In situ hybridization for c-fos revealed an absence of expression in the core region, suggesting early cessation of transcription. There was strong induction of c-fos in the penumbra 30 min after the lesion, which had spread over the ipsilateral hemisphere at 2 h, possibly caused by peri-infarction depolarization. At later time points, sustained expression of c-fos was observed in some cells in the penumbra. Since a role for c-fos has been postulated in the initiation or execution of apoptotic pathways, the susceptibility of c-fos deficient mice was explored (n=4) in this model. Cryoinjury-induced tissue injury was markedly attenuated in c-fos deficient mice. A model of the phases and mechanisms of cryogenic injury is proposed, which discriminates an early phase characterized by physical changes caused by hypothermia and their immediate consequences (i.e. transcriptional block), an intermediate phase where secondary changes lead to necrosis in the core region, and a final phase of delayed apoptotic cell death in the penumbra. [ABSTRACT FROM AUTHOR]

J. Lampe, S. Marino, A. Rethwilm and A. Aguzzi (1998) Neuropathology and Applied Neurobiology 24, 36–43 Degeneration of the cerebellar granule cell layer in transgenic mice expressing genes of human foamy virus Transgenic mice expressing various combinations of structural and regulatory genes of human foamy virus (HFV) develop a neurodegenerative syndrome. Δgpe transgenic mice (which express the auxiliary bel-1 and bet genes along with truncated forms of gag, pol, and env) develop a severe neurological syndrome consisting mainly of spastic tetraparesis and blindness, and show neuronal loss in the hippocampus and cerebral cortex. In addition, mice in two of eight Δgpe lines developed an ataxic gait. Here we studied the phenotype of these two lines, and show that these mice exhibit progressive degeneration of their cerebellar granule cells beginning at 4–8 weeks of age. Transgenic mRNA and HFV proteins accumulate in cerebellar granule cells immediately before the onset of degeneration. The Purkinje cell layer is largely unaffected by this pathological process. Probably due to the loss of granule cell processes, the cerebellar molecular layer is narrowed in the late stages of the disease. These findings indicate that HFV gene products can be neurotoxic for cerebellar granule cells. [ABSTRACT FROM AUTHOR]

The article discusses a study which assessed the proportion of chronic myeloid leukemia patients treated front line with imatinib outside clinical trials who could achieve a durable molecular response (MR) and maintain after treatment discontinuation. Topics covered include the reason for therapy restart, characteristics of patients who discontinued imatinib, and comparison of dasatinib and nilotinib with imatinib.

ABSTRACT Prion diseases are progressive, infectious neurodegenerative disorders caused primarily by the misfolding of the cellular prion protein (PrP c) into an insoluble, protease-resistant, aggregated isoform termed PrP sc. In native conditions, PrP c has a structured C-terminal domain and a highly flexible N-terminal domain. A part of this N-terminal domain consists of 4-5 repeats of an unusual glycine-rich, eight amino acids long peptide known as the octapeptide repeat (OR) domain. In this article, we successfully report the first crystal structure of an OR of PrP c bound to the Fab fragment of the POM2 antibody. The structure was solved at a resolution of 2.3 Å by molecular replacement. Although several studies have previously predicted a β-turn-like structure of the unbound ORs, our structure shows an extended conformation of the OR when bound to a molecule of the POM2 Fab indicating that the bound Fab disrupts any putative native β turn conformation of the ORs. Encouraging results from several recent studies have shown that administering small molecule ligands or antibodies targeting the OR domain of PrP result in arresting the progress of peripheral prion infections both in ex vivo and in in vivo models. This makes the structural study of the interactions of POM2 Fab with the OR domain very important as it would help us to design smaller and tighter binding OR ligands. [ABSTRACT FROM AUTHOR]

Protease-resistant prion protein (PrP) is diagnostic of prion disease, yet its detection is frequently difficult. Here, we describe a patient with a PRNP P105T mutation and typical familial prion disease. Brain PrP was undetectable by conventional Western blotting and barely detectable after phosphotungstate precipitation, where it displayed an atypical pattern suggestive of noncanonical conformation. Therefore, we used a novel misfolded protein assay (MPA) that detects PrP aggregates independently of their protease resistance. The MPA revealed the presence of aggregated PrP in similar amounts as in typical sporadic Creutzfeldt-Jakob disease. These findings suggest that measurements of PrP aggregation with the MPA may be potentially more sensitive than protease-based methodologies. [ABSTRACT FROM AUTHOR]

In 1965, Mitchell and Abbot (Mitchell, J. and Abbot A, Nature 1965. 500-502) discovered peculiar cells with filiform processes, which were capable of capturing and retaining antigens within secondary lymphoid organs. Yet half a century since the first description of follicular dendritic cells (FDC), their function and their histogenesis remain largely mysterious. FDC are thought to help with organization of the lymphoid follicles, to facilitate the germinal center reaction by presenting antigen to B cells, and to legislate the engulfment of apoptotic bodies, but it has proved difficult to stringently verify any of these functions. One reason for such slow progress is a dearth of markers specific to FDC and their precursors, which limits our ability to isolate, target, and follow FDC. Here we review the current state of FDC science with specific reference to a study in this issue of the European Journal of Immunology and its efforts in discovering new FDC markers. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD), the most common neurodegenerative disorder, goes along with extracellular amyloid-β (Aβ) deposits. The cognitive decline observed during AD progression correlates with damaged spines, dendrites and synapses in hippocampus and cortex. Numerous studies have shown that Aβ oligomers, both synthetic and derived from cultures and AD brains, potently impair synaptic structure and functions. The cellular prion protein (PrPC) was proposed to mediate this effect. We report that ablation or overexpression of PrPC had no effect on the impairment of hippocampal synaptic plasticity in a transgenic model of AD. These findings challenge the role of PrPC as a mediator of Aβ toxicity. See accompanying article: http://dx.doi.org/10.1002/emmm.2010000868. [ABSTRACT FROM AUTHOR]