Virological rebound in human immunodeficiency virus-infected patients with or without residual viraemia: results from an extended follow-up

AbstractHuman immunodeficiency virus (HIV) -infected patients with HIV RNA loads of < 50 copies/mL were followed-up for a median (interquartile range) of 30.8 (11.7–32.9) months to study the effect of residual viraemia (RV) on virological rebound (VR). At baseline, 446 (60.3%) patients had undetectable HIV RNA (group A) and 293 (39.7%) had RV (1–49 HIV RNA copies/mL, group B) by kinetic PCR. VR occurred in 4 (0.9%) patients in group A and in 12 (4.1%) patients in group B (p 0.007). Time to VR was shorter among patients of group B (Log-rank test: p 0.003). However, the proportion of VR was extremely low also among patients with RV

NMR Metabolomics for Stem Cell type discrimination

Cell metabolism is a key determinant factor for the pluripotency and fate commitment of Stem Cells (SCs) during development, ageing, pathological onset and progression. We derived and cultured selected subpopulations of rodent fetal, postnatal, adult Neural SCs (NSCs) and postnatal glial progenitors, Olfactory Ensheathing Cells (OECs), respectively from the subventricular zone (SVZ) and the olfactory bulb (OB). Cell lysates were analyzed by proton Nuclear Magnetic Resonance (1H-NMR) spectroscopy leading to metabolites identification and quantitation. Subsequent multivariate analysis of NMR data by Principal Component Analysis (PCA), and Partial Least Square Discriminant Analysis (PLS-DA) allowed data reduction and cluster analysis. This strategy ensures the definition of specific features in the metabolic content of phenotypically similar SCs sharing a common developmental origin. The metabolic fingerprints for selective metabolites or for the whole spectra demonstrated enhanced peculiarities among cell types. The key result of our work is a neat divergence between OECs and the remaining NSC cells. We also show that statistically significant differences for selective metabolites characterizes NSCs of different ages. Finally, the retrived metabolome in cell cultures correlates to the physiological SC features, thus allowing an integrated bioengineering approach for biologic fingerprints able to dissect the (neural) SC molecular specificitie

Desarrollo de habilidades de comprensión gráfica. Adaptación de una propuesta de actividades para educación secundaria

Durante el año 2020, la situación inesperada del COVID-19 obligó a virtualizar todas las prácticas educativas que antes se llevaban a cabo en las aulas. Desde una perspectiva de comunicación, a su vez, la pandemia inundó los medios masivos de gráficos estadísticos y sus análisis respectivos, influyendo sobre la opinión pública. Esta situación pone de manifiesto la necesidad de desarrollar en los estudiantes de nivel secundario, habilidades en relación a la comprensión de la información presentada en los gráficos que aparecen frecuentemente en los medios ya que esto fomenta el razonamiento crítico y forma para la ciudadanía. También les Impone a los docentes pensar una propuesta utilizando los recursos que se encuentran en el mundo de lo virtual. Virtualizar los procesos de enseñanza aprendizaje invita a que los docentes repiensen su rol pasando de ser presentadores de contenidos a diseñadores de secuencias didácticas que permitan al alumno realizar un recorrido progresivo por el contenido y desarrollar las destrezas implicadas en la temática en cuestión. Para esta tarea es clave diseñar contextos poderosos para el aprendizaje, es decir, espacios donde los estudiantes participen activamente a través de la resolución de problemas reales. En el presente trabajo se propone adaptar para el nivel secundario, una secuencia de actividades virtuales diseñada para desarrollar la comprensión de gráficos estadísticos en alumnos de carreras de Ingeniería a partir de la resolución de problemas de áreas de su interés. En esta secuencia, la problemática se relaciona con la pandemia COVID-19.Fil: Ferreri, Noemí M. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; Argentina.Fil: Pascaner, Melina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; Argentina.Fil: Martinez, Facundo. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; Argentina.Fil: Bossolasco, María Luisa. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina

Induction of neurotrophin expression via human adult mesenchymal stem cells: implication for cell therapy in neurodegenerative diseases.

In animal models of neurological disorders for cerebral ischemia, Parkinson's disease, and spinal cord lesions, transplantation of mesenchymal stem cells (MSCs) has been reported to improve functional outcome. Three mechanisms have been suggested for the effects of the MSCs: transdifferentiation of the grafted cells with replacement of degenerating neural cells, cell fusion, and neuroprotection of the dying cells. Here we demonstrate that a restricted number of cells with differentiated astroglial features can be obtained from human adult MSCs (hMSCs) both in vitro using different induction protocols and in vivo after transplantation into the developing mouse brain. We then examined the in vitro differentiation capacity of the hMSCs in coculture with slices of neonatal brain cortex. In this condition the hMSCs did not show any neuronal transdifferentiation but expressed neurotrophin low-affinity (NGFRp75) and high-affinity (trkC) receptors and released nerve growth factor (NGF) and neurotrophin-3 (NT-3). The same neurotrophin's expression was demonstrated 45 days after the intracerebral transplantation of hMSCs into nude mice with surviving astroglial cells. These data further confirm the limited capability of adult hMSC to differentiate into neurons whereas they differentiated in astroglial cells. Moreover, the secretion of neurotrophic factors combined with activation of the specific receptors of transplanted hMSCs demonstrated an alternative mechanism for neuroprotection of degenerating neurons. hMSCs are further defined in their transplantation potential for treating neurological disorders

Motor neuron differentiation of iPSCs obtained from peripheral blood of a mutant TARDBP ALS patient

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease, mainly affecting the motor neurons (MNs) and without effective therapy. Drug screening is hampered by the lack of satisfactory experimental and pre-clinical models. Induced pluripotent stem cells (iPSCs) could help to define disease mechanisms and therapeutic strategies as they could be differentiated into MNs, otherwise inaccessible from living humans. In this study, given the seminal role of TDP-43 in ALS pathophysiology, MNs were obtained from peripheral blood mononuclear cells-derived iPSCs of an ALS patient carrying a p.A382T TARDBP mutation and a healthy donor. Venous samples were preferred to fibroblasts for their ease of collection and no requirement for time consuming extended cultures before experimentation. iPSCs were characterized for expression of specific markers, spontaneously differentiated into primary germ layers and, finally, into MNs. No differences were observed between the mutated ALS patient and the control MNs with most of the cells displaying a nuclear localization of the TDP-43 protein. In conclusion, we here demonstrated for the first time that human TARDBP mutated MNs can be successfully obtained exploiting the reprogramming and differentiation ability of peripheral blood cells, an easily accessible source from any patient

Heterogeneities in leishmania infantum infection : using skin parasite burdens to identify highly infectious dogs

Background: The relationships between heterogeneities in host infection and infectiousness (transmission to arthropod vectors) can provide important insights for disease management. Here, we quantify heterogeneities in Leishmania infantum parasite numbers in reservoir and non-reservoir host populations, and relate this to their infectiousness during natural infection. Tissue parasite number was evaluated as a potential surrogate marker of host transmission potential. Methods: Parasite numbers were measured by qPCR in bone marrow and ear skin biopsies of 82 dogs and 34 crab-eating foxes collected during a longitudinal study in Amazon Brazil, for which previous data was available on infectiousness (by xenodiagnosis) and severity of infection. Results: Parasite numbers were highly aggregated both between samples and between individuals. In dogs, total parasite abundance and relative numbers in ear skin compared to bone marrow increased with the duration and severity of infection. Infectiousness to the sandfly vector was associated with high parasite numbers; parasite number in skin was the best predictor of being infectious. Crab-eating foxes, which typically present asymptomatic infection and are non-infectious, had parasite numbers comparable to those of non-infectious dogs. Conclusions: Skin parasite number provides an indirect marker of infectiousness, and could allow targeted control particularly of highly infectious dogs

Detection and Identification of Old World Leishmania by High Resolution Melt Analysis

Protozoal parasites of the genus Leishmania are transmitted by sand fly bites to humans and animals. Three major forms of disease are caused by these parasites: cutaneous leishmaniasis, responsible for disfiguring skin wounds; mucocutaneous leishmaniasis, causing non-healing ulceration around the mouth and nose; and the potentially fatal visceral leishmaniasis, involving internal organs such as the spleen and liver. More than 2 million new human infections are caused annually by leishmaniasis globally, it is endemic in more than 88 countries and prevalent also as an imported disease in non-endemic regions due to travel and tourism. Most species of Leishmania that infect humans are zoonotic and transmitted from animal reservoir hosts. As various leishmanial parasites cause disease with similar symptoms, but require different therapeutic regimens and have dissimilar prognoses, reliable, sensitive and rapid diagnostic assays are needed. This study focuses on the five main species that cause leishmaniasis in the Old World. It presents a new assay for rapid detection, species identification and quantification of leishmanial parasites in clinical samples, reservoir hosts and sand flies. This technique could be especially valuable in regions where several leishmanial species exist, in non-endemic regions where infected patients require a rapid diagnosis, and for epidemiological host and vector studies leading to prevention programs

Moderate aerobic exercise (brisk walking) increases bone density in cART-treated persons

Moderate intensity aerobic activity reduces the risk of cardiovascular disease, diabetes and metabolic syndrome in the general population and has a potential in preventing bone loss. We evaluated the effects of brisk walking, with or without strength exercise, on bone mineral density in HIV-infected treated persons. Twenty-eight HIV-infected, cART-treated, sedentary subjects with VL&#60;50 c/mL were enrolled in a 12-week exercise program, consisting of 3 outdoor sessions/week of 60 min walking at 67&#x2013;70% of HR (heart rate) max&#x00B1;30 min circuit training at 65% of 1-RM (repetition maximum). Subjects were examined at baseline (BL) and 12 weeks (W12) by 6-minute walking test (6MWT) and by counting the number of repetitions for each strength exercise; and by dual energy X-ray absorptiometry (DEXA) to evaluate lumbar spine and femoral bone mineral density with t- and z-scores - in addition to morphometric (BMI, waist, hip and leg circumference) and blood examination (cytometry, fasting total, HDL and LDL cholesterol, triglycerides, glucose, insulin; AST/ALT, ALP, gGT, creatinine, CPK, HbA1c; CD4+ and CD8+, plasma HIV-RNA). Differences over time were tested by Wilcoxon-signed rank test and between groups by Mann-Whitney test. Twenty-seven (96%) participants (19M, 8F; median 48 y-o, IQR 43&#x2013;54; median CD4+624/&#x00B5;L, IQR 478&#x2013;708; ART with PI: 13 patients, with NNRTI: 7 patients, and including TDF: 15 patients) completed the 12-week program with a median adherence of 61% (IQR 50&#x2013;70): 18 in the &#x2018;walk only&#x2019; only group and 9 in the &#x2018;walk and strength&#x2019; group. At W12, participants showed significant improvement of distance by 6MWT (Table), and of performance in all strength exercises (crunch p=0.023, lat machine p=0.016, chest press p=0.016, leg extension p=0.016, sitting calf p=0.008, leg press p=0.016). DEXA spine z-score improved significantly in the whole group, and femoral z-scores in the &#x2018;walk only&#x2019; group. There was no z-score difference at BL between patients with/out PIs, NNRTIs or TDF. However, spine z-score improved significantly in patients receiving TDF. At W12 BMI, waist circumference, and LDL also improved significantly in the whole group, whereas no significant changes were observed for the other variables, The above 12-week program improved fitness and bone density in HIV-infected treated subjects, in addition to some morphometric variables and serum LDL. Brisk walking, with or without strength exercise, might help control the long-term consequences of cART

Neuronal hypoxia in vitro: Investigation of therapeutic principles of HUCB-MNC and CD133+ stem cells

Background The therapeutic capacity of human umbilical cord blood mononuclear cells (HUCB-MNC) and stem cells derived thereof is documented in animal models of focal cerebral ischemia, while mechanisms behind the reduction of lesion size and the observed improvement of behavioral skills still remain poorly understood. Methods A human in vitro model of neuronal hypoxia was used to address the impact of total HUCB-MNC (tMNC), a stem cell enriched fraction (CD133+, 97.38% CD133-positive cells) and a stem cell depleted fraction (CD133-, 0.06% CD133-positive cells) of HUCB-MNC by either direct or indirect co-cultivation with post-hypoxic neuronal cells (differentiated SH-SY5Y). Over three days, development of apoptosis and necrosis of neuronal cells, chemotaxis of MNC and production of chemokines (CCL2, CCL3, CCL5, CXCL8, CXCL9) and growth factors (G-CSF, GM-CSF, VEGF, bFGF) were analyzed using fluorescence microscopy, FACS and cytometric bead array. Results tMNC, CD133+ and surprisingly CD133- reduced neuronal apoptosis in direct co-cultivations significantly to levels in the range of normoxic controls (7% ± 3%). Untreated post-hypoxic control cultures showed apoptosis rates of 85% ± 11%. tMNC actively migrated towards injured neuronal cells. Both co-cultivation types using tMNC or CD133- reduced apoptosis comparably. CD133- produced high concentrations of CCL3 and neuroprotective G-CSF within indirect co-cultures. Soluble factors produced by CD133+ cells were not detectable in direct co-cultures. Conclusion Our data show that heterogeneous tMNC and even CD133-depleted fractions have the capability not only to reduce apoptosis in neuronal cells but also to trigger the retaining of neuronal phenotypes