Tissue culture of immortal cell strains from diseased patients is an invaluable resource for medical research but is largely limited to tumor cell lines or transformed derivatives of native tissues. ...Here we describe the generation of induced pluripotent stem (iPS) cells from patients with a variety of genetic diseases with either Mendelian or complex inheritance; these diseases include adenosine deaminase deficiency-related severe combined immunodeficiency (ADA-SCID), Shwachman-Bodian-Diamond syndrome (SBDS), Gaucher disease (GD) type III, Duchenne (DMD) and Becker muscular dystrophy (BMD), Parkinson disease (PD), Huntington disease (HD), juvenile-onset, type 1 diabetes mellitus (JDM), Down syndrome (DS)/trisomy 21, and the carrier state of Lesch-Nyhan syndrome. Such disease-specific stem cells offer an unprecedented opportunity to recapitulate both normal and pathologic human tissue formation in vitro, thereby enabling disease investigation and drug development.
Purpose
Telemedicine care dramatically expanded during the COVID-19 pandemic. We characterized facilitators and barriers to telemedicine implementation among safety-net primary care clinics serving ...patients with limited English proficiency (LEP).
Methods
We collected data on telemedicine volume and patient demographics among safety-net clinics participating in a telemedicine learning collaborative. Data on various metrics were reported to the collaborative from February 2019 through August 2021. We conducted semi-structured interviews with clinical and quality leaders, purposively sampling clinics serving high proportions of patients with LEP. We analyzed interviews with a mixed inductive-deductive approach applying the Consolidated Framework for Implementation Research.
Results
By September 2020, the 23 sites served 121,589 unique patients with in-person and 120,338 with telephone visits; 47% of these patients had LEP. Of 10,897 unique patients served by video visits, 38% had LEP. As a proportion of total visits, telemedicine (telephone and video) visits increased from 0–17% in October 2019–March 2020 to 10–98% in March–August 2020. We conducted 14 interviews at 11 sites. Themes included (1) existing telemedicine platforms and interpreter services were not optimized to support patients with LEP; (2) clinics invested significant labor iterating workflows; (3) sites with technological infrastructure and language-concordant staff were best suited to serve patients; (4) patients speaking less-represented languages or experiencing intersecting literacy barriers were underserved with telemedicine. Interviewees recommended innovations in telemedicine platforms and community-based access.
Conclusions
Safety-net sites relied on existing resources to accommodate patients with LEP, but struggled providing access for the most marginalized. Proactive, data-driven strategies to address patient and community barriers as well as optimize clinical workflows with high-quality, certified medical interpreters are needed to ensure equitable access.
Human pluripotent stem cells (hPSCs) represent a promising source of patient-specific cells for disease modeling, drug screens, and cellular therapies. However, the inability to derive engraftable ...human hematopoietic stem and progenitor cells (HSPCs) has limited their characterization to in vitro assays. We report a strategy to respecify lineage-restricted CD34+CD45+ myeloid precursors derived from hPSCs into multilineage progenitors that can be expanded in vitro and engrafted in vivo. HOXA9, ERG, and RORA conferred self-renewal and multilineage potential in vitro and maintained primitive CD34+CD38− cells. Screening cells via transplantation revealed that two additional factors, SOX4 and MYB, conferred engraftment. Progenitors specified with all five factors gave rise to reproducible short-term engraftment with myeloid and erythroid lineages. Erythroid precursors underwent hemoglobin switching in vivo, silencing embryonic and activating adult globin expression. Our combinatorial screening approach establishes a strategy for obtaining transcription-factor-mediated engraftment of blood progenitors from human pluripotent cells.
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•Respecification is a strategy to generate HSCs from committed progenitors•ERG, HOXA9, and RORA induce multipotent progenitors from human IPSCs•Addition of SOX4 and MYB enables robust short-term erythro-myeloid transplant•Engrafted human erythroblasts mature and undergo hemoglobin switching
A strategy for making transplantable hematopoietic cells from human pluripotent cells involving transcription-factor-based induction of stem-cell-like properties in differentiated progenitors.
Yaws affects children in tropical regions, while syphilis primarily affects sexually active adults worldwide. Despite various campaigns towards the eradication of yaws and elimination of syphilis, ...these two diseases are still present in Ghana. The aetiological agents of both diseases, two Treponema pallidum subspecies, are genetically similar. This study aimed to assess the prevalence of these treponematoses and the occurrence of pathogens causing similar skin lesions in the Ashanti region of Ghana. A point-of-care test was used to determine the seroprevalence of the treponematoses. Both yaws and syphilis were identified in the Ashanti region of Ghana. Multiplex PCR was used to identify treponemes and other pathogens that cause similar skin lesions. The results indicated that the seroprevalences of T. pallidum in individuals with yaws-like and syphilis-like lesions were 17.2% and 10.8%, respectively. Multiplex PCR results showed that 9.1%, 1.8% and 0.9% of yaws-like lesions were positive for Haemophilus ducreyi, herpes simplex virus-1 (HSV-1) and T. pallidum respectively. Among syphilis-like lesions, 28.3% were positive for herpes simplex virus -2 (HSV-2) by PCR. To our knowledge, this is the first time HSV-I and HSV-2 have been reported from yaws-like and syphilis-like lesions, respectively, in Ghana. The presence of other organisms apart from T. pallidum in yaws-like and syphilis-like lesions could impede the total healing of these lesions and the full recovery of patients. This may complicate efforts to achieve yaws eradication by 2030 and the elimination of syphilis and warrants updated empirical treatment guidelines for skin ulcer diseases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Syphilis is an important public health problem and an increasing incidence has been noted in recent years. Characterization of strain diversity through molecular data plays a critical role in the ...epidemiological understanding of this re-emergence. We here propose a new high-resolution multilocus sequence typing (MLST) scheme for Treponema pallidum subsp. pallidum (TPA). We analyzed 30 complete and draft TPA genomes obtained directly from clinical samples or from rabbit propagated strains to identify suitable typing loci and tested the new scheme on 120 clinical samples collected in Switzerland and France. Our analyses yielded three loci with high discriminatory power: TP0136, TP0548, and TP0705. Together with analysis of the 23S rRNA gene mutations for macrolide resistance, we propose these loci as MLST for TPA. Among clinical samples, 23 allelic profiles as well as a high percentage (80% samples) of macrolide resistance were revealed. The new MLST has higher discriminatory power compared to previous typing schemes, enabling distinction of TPA from other treponemal bacteria, distinction between the two main TPA clades (Nichols and SS14), and differentiation of strains within these clades.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Loss of kidney function underlies many renal diseases. Mammals can partly repair their nephrons (the functional units of the kidney), but cannot form new ones. By contrast, fish add nephrons ...throughout their lifespan and regenerate nephrons de novo after injury, providing a model for understanding how mammalian renal regeneration may be therapeutically activated. Here we trace the source of new nephrons in the adult zebrafish to small cellular aggregates containing nephron progenitors. Transplantation of single aggregates comprising 10-30 cells is sufficient to engraft adults and generate multiple nephrons. Serial transplantation experiments to test self-renewal revealed that nephron progenitors are long-lived and possess significant replicative potential, consistent with stem-cell activity. Transplantation of mixed nephron progenitors tagged with either green or red fluorescent proteins yielded some mosaic nephrons, indicating that multiple nephron progenitors contribute to a single nephron. Consistent with this, live imaging of nephron formation in transparent larvae showed that nephrogenic aggregates form by the coalescence of multiple cells and then differentiate into nephrons. Taken together, these data demonstrate that the zebrafish kidney probably contains self-renewing nephron stem/progenitor cells. The identification of these cells paves the way to isolating or engineering the equivalent cells in mammals and developing novel renal regenerative therapies.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Temporal manipulation of the
environment and growth factors can direct differentiation of human pluripotent stem cells into organoids - aggregates with multiple tissue-specific cell types and ...three-dimensional structure mimicking native organs. A mechanistic understanding of early organoid formation is essential for improving the robustness of these methods, which is necessary prior to use in drug development and regenerative medicine. We investigated intestinal organoid emergence, focusing on measurable parameters of hindgut spheroids, the intermediate step between definitive endoderm and mature organoids. We found that 13% of spheroids were pre-organoids that matured into intestinal organoids. Spheroids varied by several structural parameters: cell number, diameter and morphology. Hypothesizing that diameter and the morphological feature of an inner mass were key parameters for spheroid maturation, we sorted spheroids using an automated micropipette aspiration and release system and monitored the cultures for organoid formation. We discovered that populations of spheroids with a diameter greater than 75 μm and an inner mass are enriched 1.5- and 3.8-fold for pre-organoids, respectively, thus providing rational guidelines towards establishing a robust protocol for high quality intestinal organoids.
Mating systems are thought to be an important determinant of dispersal strategies in most animals, including the great apes. As the most basal taxon of all great apes, orang‐utans can provide ...information about the evolution of mating systems and their consequences for population structure in this Family. To assess the sex‐specific population structure in orang‐utans, we used a combination of paternally transmitted Y‐chromosomal genetic markers and maternally transmitted mitochondrial DNA sequences. Markers transmitted through the more philopatric sex are expected to show stronger differentiation among populations than the ones transmitted through the dispersing sex. We studied these patterns using 70 genetic samples from wild orang‐utans from seven Bornean and two Sumatran populations. We found pronounced population structure in haplotype networks of mitochondrial sequence data, but much less so for male‐specific markers. Similarly, mitochondrial genetic differentiation was twice as high among populations compared to Y‐chromosomal variation. We also found that genetic distance increased faster with geographic distance for mitochondrial than for Y‐linked markers, leading to estimates of male dispersal distances that are several‐fold higher than those of females. These findings provide evidence for strong male‐biased dispersal in orang‐utans. The transition to predominantly female‐biased dispersal in the great ape lineage appears to be correlated with life in multimale groups and may reflect the associated fitness benefits of reliable male coalitions with relatives or known partners, a feature that is absent in orang‐utans.
Blood flow promotes emergence of definitive hematopoietic stem cells (HSCs) in the developing embryo, yet the signals generated by hemodynamic forces that influence hematopoietic potential remain ...poorly defined. Here we show that fluid shear stress endows long-term multilineage engraftment potential upon early hematopoietic tissues at embryonic day 9.5, an embryonic stage not previously described to harbor HSCs. Effects on hematopoiesis are mediated in part by a cascade downstream of wall shear stress that involves calcium efflux and stimulation of the prostaglandin E2 (PGE2)-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling axis. Blockade of the PGE2-cAMP-PKA pathway in the aorta-gonad-mesonephros (AGM) abolished enhancement in hematopoietic activity. Furthermore, Ncx1 heartbeat mutants, as well as static cultures of AGM, exhibit lower levels of expression of prostaglandin synthases and reduced phosphorylation of the cAMP response element-binding protein (CREB). Similar to flow-exposed cultures, transient treatment of AGM with the synthetic analogue 16,16-dimethyl-PGE2 stimulates more robust engraftment of adult recipients and greater lymphoid reconstitution. These data provide one mechanism by which biomechanical forces induced by blood flow modulate hematopoietic potential.
Levamisole has recently been implicated as a cause of cutaneous vasculopathy in cocaine abusers. The objective of this study was to describe this relatively new entity by reviewing published cases ...identified through a literature search.
Published reports identified through a search of PubMed database (from 1964 to November 2011) were reviewed to record clinical, serological and pathologic findings.
A cohort of 32 patients had a mean age of 44 ± 9 years with a female predominance (75%). Rash predominately affected lower extremities (87.5%), followed by face (78%) and ears (69%) and typically presented as purpuric plaques, which were seen in a retiform pattern in 16 (50%) and had central necrosis in 11 patients (34%). Leukopenia and neutropenia were found in 20 patients (63%). Antinuclear cytoplasmic antibody (ANCA) was positive in 30 patients (94%); p-ANCA in 28 patients (87.5%), c-ANCA in 19 (59%) and both in 17 patients (53%). Skin biopsy results were available for 29 patients: 14 (48%) had pure thrombotic vasculopathy, 4 (14%) had pure small vessel vasculitis and 11 (38%) had evidence of both. Treatment information was available for 30 patients. Only supportive care was given to 11 patients (37%), steroids to 16 (53%) and surgical treatment for 5 (17%). Clinical course of lesions was available for 24 patients. Rash resolved in 11 patients (46%) and improved in 13 (54%). During median follow-up of 21 days (range, 7-270 days), 10 of 22 patients had recurrences related to cocaine use.
Levamisole-induced cutaneous vasculopathy in cocaine users is characterized by a female predominance, a retiform purpuric rash with a predilection for lower extremities, autoantibody production, leukopenia and/or neutropenia and recurrences with future cocaine use.
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