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The objective of this study was to verify the applicability and preliminary results of an ultrasound methodology for the complete characterization of root wood. The tests utilized six species: Swietenia macrophylla, Gallesia integrifólia, Swietenia sp., Schinus molle, Handroanthus heptaphyllus, and Acrocarpus fraxinifolius. The results show expected elastic ratios between properties, indicating that although the properties can differ numerically from roots and other parts of the tree, the orthotropic wood behavior is maintained. The root densities were higher than those reported in the literature for trunk wood, but direct relationships among high density and stiffness or strength properties were not observed. The ultrasound tests allowed 12 elastic constants of root wood to be obtained and were feasible for root dimensions because only one specimen was required. [ABSTRACT FROM AUTHOR]

Purpose: The complement system is a crucial part of innate immunity. Recent work demonstrated an unexpected contribution to tissue homeostasis and degeneration. This study investigated for the first time, in human disc tissues, the deposition profile of the complement activation product terminal complement complex (TCC), an inflammatory trigger and inducer of cell lysis, and its inhibitor CD59, and their correlation with the degree of disc degeneration (DD). Methods: Disc biopsies were collected from patients diagnosed with DD (n = 39, age 63 ± 12) and adolescent idiopathic scoliosis (AIS, n = 10, age 17 ± 4) and compared with discs from healthy Young (n = 11, age 7 ± 7) and Elder (n = 10, age 65 ± 15) donors. Immunohistochemical detection of TCC and CD59 in nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) was correlated with age, Pfirrmann grade and Modic changes. Results: Higher percentage of TCC+ cells was detected in the NP and EP of DD compared to Elder (P < 0.05), and in the EP of Young versus Elder (P < 0.001). In DD, TCC deposition was positively correlated with Pfirrmann grade, but not with Modic changes, whereas for Young donors, a negative correlation was found with age, indicating TCC's involvement not only in DD, but also in early stages of skeletal development. Higher CD59 positivity was found in AIS and DD groups compared to Young (P < 0.05), and it was negatively correlated with the age of the patients. Conclusion: TCC deposition positively correlated with the degree of disc degeneration. A functional relevance of TCC may exist in DD, representing a potential target for new therapeutics. [ABSTRACT FROM AUTHOR]

Introduction: Cirrhosis is one of the major causes of morbidity and mortality worldwide. Portal hypertension is the major contributor of cirrhosis‐related complications and is defined as a hepatic venous pressure gradient (HVPG) > 5 mmHg. Measurement of HVPG is an invasive, difficult, and costly procedure. Therefore, it is only performed in specialized centers. Liver stiffness measured with transient elastography is one of the most studied noninvasive markers of portal hypertension, and spleen elastography has recently emerged as an important adjuvant tool. The development of a new probe (100 Hz) that more reliably reflect the grade of portal hypertension evaluated by spleen stiffness measurement has improved the accuracy of this technique. The aim of this work was to evaluate the accuracy of spleen stiffness with the new dedicated probe to predict the presence of high‐risk varices, as well as to determine the ideal cutoff to predict it. Methods: Prospective study of cirrhotic patients admitted to upper endoscopy that were also submitted to liver and spleen elastography with the 100‐Hz probe by the same blinded operator in a tertiary center. Results: We included 209 cirrhotic patients, with mean age of 61.9 years (±9.9), 77.0% male. The most common etiology was alcoholic liver disease (72.7%). The median value of liver elastography was 25.3 [4.5–75] kPa, and the median value of spleen elastography was 42.4 [7.6–100] kPa. At the cutoff of 53.25 kPa, we obtained sensitivity of 100% and specificity of 72.6% to predict high‐risk varices, and, according to this cutoff, 133/175 of esophagogastroduodenoscopy could have been spared (76.0%), while according to Baveno guidelines, only 51/175 would have been spared (29.1%). Conclusion: In the era of noninvasive exams, spleen elastography with the 100‐Hz probe emerges as an excellent tool for prediction of presence of high‐risk varices. At the cutoff of 53.25 kPa, spleen elastography avoids upper endoscopy for screening for high‐risk varices, promising to be become part of the hepatologists' daily routine. [ABSTRACT FROM AUTHOR]

Purpose: Formation of terminal complement complex (TCC), a downstream complement system activation product inducing inflammatory processes and cell lysis, has been identified in degenerated discs. However, it remains unclear which molecular factors regulate complement activation during disc degeneration (DD). This study investigated a possible involvement of the pro-inflammatory cytokine interleukin-1β (IL-1β) and the lysosomal protease cathepsin D (CTSD). Methods: Disc biopsies were collected from patients suffering from DD (n = 43) and adolescent idiopathic scoliosis (AIS, n = 13). Standardized tissue punches and isolated cells from nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) were stimulated with 5% human serum (HS) alone or in combination with IL-1β, CTSD or zymosan. TCC formation and modulation by the complement regulatory proteins CD46, CD55 and CD59 were analysed. Results: In DD tissue cultures, IL-1β stimulation decreased the percentage of TCC + cells in AF and EP (P < 0.05), whereas CTSD stimulation significantly increased TCC deposition in NP (P < 0.01) and zymosan in EP (P < 0.05). Overall, the expression of CD46, CD55 and CD59 significantly increased in all isolated cells during culture (P < 0.05). Moreover, cellular TCC deposition was HS concentration dependent but unaffected by IL-1β, CTSD or zymosan. Conclusion: These results suggest a functional relevance of IL-1β and CTSD in modulating TCC formation in DD, with differences between tissue regions. Although strong TCC deposition may represent a degeneration-associated event, IL-1β may inhibit it. In contrast, TCC formation was shown to be triggered by CTSD, indicating a multifunctional involvement in disc pathophysiology. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy of a synthetic sex-aggregation pheromone of the sand fly vector Lu. longipalpis, co-located with residual insecticide, to reduce the infection incidence of Leishmania infantum in the canine reservoir. A stratified cluster randomised trial was designed to detect a 50% reduction in canine incident infection after 24 months in 42 recruited clusters, randomly assigned to one of three intervention arms (14 cluster each): synthetic pheromone + insecticide, insecticide-impregnated dog collars, or placebo control. Infection incidence was measured by seroconversion to anti-Leishmania serum antibody, Leishmania parasite detection and canine tissue parasite loads. Changes in relative Lu. longipalpis abundance within households were measured by setting three CDC light traps per household. A total 1,454 seronegative dogs were followed-up for a median 15.2 (95% C.I.s: 14.6, 16.2) months per cluster. The pheromone + insecticide intervention provided 13% (95% C.I. 0%, 44.0%) protection against anti-Leishmania antibody seroconversion, 52% (95% C.I. 6.2%, 74·9%) against parasite infection, reduced tissue parasite loads by 53% (95% C.I. 5.4%, 76.7%), and reduced household female sand fly abundance by 49% (95% C.I. 8.2%, 71.3%). Variation in the efficacy against seroconversion varied between trial strata. Equivalent protection attributed to the impregnated-collars were 36% (95% C.I. 14.4%, 51.8%), 23% (95% C.I. 0%, 57·5%), 48% (95% C.I. 0%, 73.4%) and 43% (95% C.I. 0%, 67.9%), respectively. Comparison of the two interventions showed no statistically consistent differences in their efficacies; however, the errors were broad for all outcomes. Reductions in sand fly numbers were predominant where insecticide was located (chicken and dog sleeping sites), with no evidence of insecticide-induced repellence onto humans or dogs. The synthetic pheromone co-located with insecticide provides protection particularly against canine L. infantum parasite transmission and sand fly vector abundance. The effect estimates are not dissimilar to those of the insecticide-impregnated collars, which are documented to reduce canine infection incidence, human infection and clinical VL disease incidence, in different global regions. The trialled novel lure-and-kill approach is a low-cost potential vector control tool against ZVL in the Americas. The predominant sand fly vector of the intracellular parasite Leishmania infantum, that causes human and canine visceral leishmaniasis in the Americas, is Lutzomyia longipalpis. Dogs are the proven reservoir. Vector control tools to reduce transmission suited to this predominantly exophilic vector are lacking. Insecticide-impregnated dog collars protect dogs against infectious bites from sand fly vectors, and result in reductions of new infections in both dogs and humans. However, collars are costly for endemic communities, and alternative approaches are needed. Recently the bulk synthesised sex-aggregation pheromone of male Lu. longipalpis was shown to attract large numbers of conspecific females to lethal pyrethroid insecticides, indicating the potential for use in a vector control application. This study, conducted in Brazil, evaluated the efficacy of this novel lure-and-kill approach to reduce seroconversion and infection incidence with L. infantum in the canine reservoir, in addition to measuring its impact on household abundance of Lu. longipalpis. Deployed in 14 stratified clusters, the outcomes were compared to those attributed to insecticide impregnated collars fitted to dogs in another 14 clusters; each intervention was compared to 14 clusters that received placebo treatments. The beneficial effects of the lure-and-kill method were most noticeable on confirmed infection incidence and clinical parasite loads, and in reducing sand fly abundance. The overall effect of the two interventions were not statistically dissimilar, though the confidence intervals were broad. We conclude that the novel low-cost lure-and-kill approach should be added to the vector control toolbox against visceral leishmaniasis in the Americas. [ABSTRACT FROM AUTHOR]

Purpose: The pathomechanism of annulus fibrosus (AF) failure is still unknown. We hypothesise that mechanical overload and an inflammatory microenvironment contribute to AF structural weakening. Therefore, the objective of this study was to investigate the influence of these factors on the AF, particularly the translamellar bridging network (TLBN) which connects the AF lamellae.Methods: A bovine AF organ culture (AF-OC) model of standardised AF rings was used to study the individual and combined effects of cyclic tensile strain (CTS) and IL-1β (1 ng/mL) culture medium supplementation. AF-OCs were analysed for PGE2 production (ELISA) and deposition of IL-6, COX-2, fibrillin, and MMP3 in the tissue (immunohistochemistry, IHC). The mechanical strength of the TLBN was evaluated using a peel test to measure the strength required to separate an AF segment along a lamellar bound.Results: The combination of CTS + IL-1β led to a significant increase in PGE2 production compared to Control (p < 0.01). IHC evaluations showed that the CTS + IL-1β group exhibited higher production of COX-2 and MMP3 within the TLBN regions compared to the adjacent lamellae and a significant increase in IL-6 ratio compared to Control (p < 0.05). A significant decrease in the annular peel strength was observed in the CTS + IL1β group compared to Control (p < 0.05).Conclusion: Our findings suggest that CTS and IL-1β act synergistically to increase pro-inflammatory and catabolic molecules within the AF, particularly the TLBN, leading to a weakening of the tissue. This standardised model enables the investigation of AF/TLBN structure-function relationship and is a platform to test AF-focused therapeutics. These slides can be retrieved under Electronic Supplementary Material. [ABSTRACT FROM AUTHOR]

Background: Despite large-scale reductions in Chagas disease prevalence across Central and South America, Trypanosoma cruzi infection remains a considerable public health problem in the Gran Chaco region where vectorborne transmission persists. In these communities, peridomestic animals are major blood-meal sources for triatomines, and household presence of infected dogs increases T. cruzi transmission risk for humans. To address the pressing need for field-friendly, complementary methods to reduce triatomine infestation and interrupt T. cruzi transmission, this study evaluated the systemic activity of three commercial, oral, single dose insecticides Fluralaner (Bravecto®), Afoxolaner (NexGard®) and Spinosad (Comfortis®) in canine feed-through assays against Triatoma infestans, the principal domestic vector species in the Southern Cone of South America. Methods: Twelve healthy, outbred dogs were recruited from the Zoonosis Surveillance and Control Program in Santa Cruz, Bolivia, and randomized to three treatment groups, each containing one control and three treated dogs. Following oral drug administration, colony-reared second and third stage T. infestans instars were offered to feed on dogs for 30 min at 2, 7, 21, 34 and 51 days post-treatment. Results: Eighty-five per cent (768/907) of T. infestans successfully blood-fed during bioassays, with significantly higher proportions of bugs becoming fully-engorged when exposed to Bravecto® treated dogs (P < 0.001) for reasons unknown. Exposure to Bravecto® or NexGard® induced 100% triatomine mortality in fully- or semi-engorged bugs within 5 days of feeding for the entire follow-up period. The lethality effect for Comfortis® was much lower (50-70%) and declined almost entirely after 51 days. Instead Comfortis® treatment resulted in substantial morbidity; of these, 30% fully recovered whereas 53% remained morbid after 120 h, the latter subsequently unable to feed 30 days later. Conclusions: A single oral dose of Fluralaner or Afoxolaner was safe and well tolerated, producing complete triatomine mortality on treated dogs over 7.3 weeks. While both drugs were highly efficacious, more bugs exposed to Fluralaner took complete blood-meals, and experienced rapid knock-down. Coupled with its longer residual activity, Fluralaner represents an ideal insecticide for development into a complementary, operationally-feasible, community-level method of reducing triatomine infestation and potentially controlling T. cruzi transmission, in the Gran Chaco region. [ABSTRACT FROM AUTHOR]

Human mesenchymal stem cells (MSC) have been on the focus of intense clinical-oriented research due to their multilineage differentiation potential and immunomodulatory properties. However, to reach the clinically meaningful cell numbers for cellular therapy and tissue engineering applications, MSC ex- vivo expansion is mandatory but sequential cell passaging results in loss of proliferative, clonogenic and differentiation potential. To get clues into the molecular mechanisms underlying cellular senescence resulting from extended ex- vivo cultivation of bone marrow (BM) MSC, we explored a two-dimensional gel electrophoresis (2-DE) based quantitative proteomics to compare the expression programs of Passage 3 cells (P3), commonly used in clinical studies with expanded MSC, and Passage 7 (P7) cells, which already demonstrated significant signs of culture-induced senescence. Proteins of the functional categories "Structural components and cellular cytoskeleton" and "Folding and stress response proteins" are less abundant in P7 cells, compared to P3, while proteins involved in "Energy metabolism", "Cell cycle regulation and aging" and "Apoptosis" are more abundant. The large number of multiple size and charge isoforms with an altered content that were identified in this study in P7 versus P3, namely the cytoskeleton components β-actin (7 forms) and vimentin (24 forms), also emphasizes the importance of post-transcriptional modification upon long-term cultivation. The differential protein expression registered suggests that cellular senescence occurring during ex-vivo expansion of BM MSC is associated with the impairment of cytoskeleton remodeling and/or organization and the repair of damaged proteins resulting from cell exposure to culture stress. The genome-wide expression approach used in this study has proven useful for getting mechanistic insights into the observed decrease on the proliferative and clonogenic potential of P7 versus P3 cells and paves the way to set up a proteome profiling strategy for quality control to assure safe and clinically effective expanded MSC. [ABSTRACT FROM AUTHOR]

Inflammation is central in intervertebral disc (IVD) degeneration/regeneration mechanisms, and its balance is crucial to maintain tissue homeostasis. This work investigates the modulation of local and systemic inflammatory response associated with IVD degeneration/herniation by administration of PRO- versus ANTI-inflammatory treatments. Chitosan/poly-γ-glutamic acid nanocomplexes, known as pro-inflammatory (PRO), and soluble diclofenac, a non-steroidal anti-inflammatory drug (ANTI), were intradiscally administered in a rat IVD injury model, 24 h after lesion. Two weeks after administration, a reduction of disc height accompanied by hernia formation was observed. In the PRO-inflammatory treated group, IL-1β, IL-6 and COX-2 IVD gene expression were upregulated, and loss of nucleus pulposus (NP) structure and composition was observed. Systemically, lower T-cell frequency was observed in the lymph nodes (LN) and spleen (SP) of the PRO group, together with an increase in CD4+ T cells subset in the blood (BL) and LN. In contrast, the ANTI-group had higher proteoglycans/collagen ratio and collagen type 2 content in the NP, while an increase in the frequency of myeloid cells, M1 macrophages and activated macrophages (MHCII+) was observed at the systemic level. Overall, this study illustrates the dynamics of local and systemic inflammatory and immune cell responses associated with intradiscal therapies, which will contribute to designing more successful immunomodulatory treatments for IVD degeneration. [ABSTRACT FROM AUTHOR]

Study Design: Ex vivo experimental study.Objective: To investigate the effect of proinflammatory/degenerative intervertebral disc (IVD) microenvironment on the regenerative and immunomodulatory behavior of mesenchymal stem/stromal cells (MSCs), using an ex vivo model from bovine origin.Summary Of Background Data: Low back pain is a cause of disability worldwide, most frequently associated with IVD degeneration and inflammation, and characterized by increased levels of inflammatory mediators, often disregarded. MSC-based therapies to low back pain have been advocated, but the involvement of inflammation in IVD remodeling mechanism, promoted by MSCs has not yet been explored.Methods: Bovine IVD organ cultures of nucleus pulposus punches were stimulated with needle puncture and culture medium supplementation with 10 ng/mL of interleukin (IL)-1β, to induce a proinflammatory/degenerative environment, as previously established. Human bone marrow-derived MSCs were cultured on top of transwells, placed above nucleus pulposus punches, for up to 16 days. MSCs were analyzed by screening cell viability/apoptosis, metabolic activity, migration, and inflammatory cytokines production in response to the proinflammatory environment. IVD extracellular matrix (ECM) remodeling, gene expression profile of IVD cells, and inflammatory cytokine profile in the presence of MSCs in basal versus proinflammatory conditions were also evaluated.Results: Proinflammatory/degenerative IVD conditions did not affect MSCs viability, but promoted cell migration, while increasing IL-6, IL-8, monocyte chemoattractant protein-1, and prostaglandin E2 and reducing transforming growth factor-β1 production by MSCs. MSCs did not stimulate ECM production (namely type II collagen or aggrecan) in neither basal nor inflammatory conditions, instead MSCs downregulated bovine proinflammatory IL-6, IL-8, and TNF-α gene expression levels in IL-1β-stimulated IVDs.Conclusion: The present study provides evidence for an immunomodulatory paracrine effect of MSCs in degenerated IVD without an apparent effect in ECM remodeling, and suggest an MSCs mechanism-of-action dependent on a cytokine feedback loop.Level Of Evidence: 5. [ABSTRACT FROM AUTHOR]