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This study investigates the drying of garlic and onion in Arequipa,considering their susceptibility to rain during times of harvest and planting.Drying costs were evaluated with different thicknesses and temperatures: 2 mm,3 mm and 4 mm for onion, and 3 mm and 5 mm for garlic, at both 50° and 60°C. Initial moisture contents of 49.75% for garlic and 87.59% for onion were determined. The drying process at 50°C fluctuated between 720-1020 minutes (onion) and 960-1020 minutes (garlic), while at 60 °C they ranged between 540-720 minutes (onion) and 540-720 minutes (garlic). No significant differences in thickness were found at both temperatures for both products, but were found when increasing from 50°C to 60°C. Energy consumption was also calculated. The results showed that the lowest cost for the garlic drying process was reached with a thickness of 3 mm and a temperature of 60°C, at a cost of 7.25 USD. In the case of onion, the lowest cost was obtained at 60 °C and a thickness of 2 mm, at a cost of 4.25 USD.

During intraerythrocytic development, Plasmodium falciparum exports proteins that interact with the host cell plasma membrane and subplasma membrane-associated spectrin network. Parasite-exported proteins modify mechanical properties of host RBCs, resulting in altered cell circulation. In this work, optical tweezers experiments of cell mechanical properties at normal physiological and febrile temperatures are coupled, for the first time, with targeted gene disruption techniques to measure the effect of a single parasite-exported protein on host RBC deformability. We investigate Pf155/Ring-infected erythrocyte surface antigen (RESA), a parasite protein transported to the host spectrin network, on deformability of ring-stage parasite-harboring human RBCs. Using a set of parental, gene-disrupted, and revertant isogenic clones, we found that RESA plays a major role in reducing deformability of host cells at the early ring stage of parasite development, but not at more advanced stage. We also show that the effect of RESA on deformability is more pronounced at febrile temperature, which ring-stage parasite-harboring RBCs can be exposed to during a malaria attack, than at normal body temperature. [ABSTRACT FROM AUTHOR]

Abstract A prospective study was undertaken to define early predictive immunological marker(s) of exposure to Leishmania in naïve subjects who have never been exposed to any Leishmania and who were also free of any cutaneous leishmaniasis lesions. These naïve subjects could have been exposed to Leishmania in a rain forest where Leishmania guyanensis and their natural vectors and mammalian host are cocirculating. The production of interferon (IFN)-γ in response to the Leishmania homologue of the mammalian receptor for activated c kinase (LACK), a candidate for vaccine against leishmaniasis was analysed. At the end of their stay in the rain forest, LACK-specific CD8+ T cells were detected in subjects whose peripheral blood mononuclear cell (PBMC) produced IFN-γ in response to soluble Leishmania antigens (SLA) and in those whose PBMC remained unresponsive to SLA. However, LACK-specific CD4+ T cells were detected only in PBMCs from individuals who became IFN-γ responders to SLA. In subjects whose PBMC became positive to SLA, LACK-reactive CD4+ T cells producing high level of IFN-γ were detectable before the SLA-reactive IFN-γ producing CD4+ T cells, suggesting that the former readout assay could be used as an early predictive immunological marker of exposure to Leishmania in subjects who remained disease free. [ABSTRACT FROM AUTHOR]

We studied the sequence of cellular events leading to the dissemination of Listeria monocytogenes from the gut to draining mesenteric lymph nodes (MLNs) by confocal microscopy of immunostained tissue sections from a rat ligated ileal loop system. OX-62-positive cells beneath the epithelial lining of Peyer's patches (PPs) were the first Listeria targets identified after intestinal inoculation. These cells had other features typical of dendritic cells (DCs): they were large, pleiomorphic and major histocompatibility complex class ll[sup hi]. Listeria were detected by microscopy in draining MLNs as early as 6h after inoculation. Some 80-90% of bacteria were located in the deep paracortical regions, and 100% of the bacteria were present in OX-62-positive cells. Most infected cells contained more than five bacteria each, suggesting that they had arrived already loaded with bacteria. At later stages, the bacteria in these areas were mostly present in ED1-positive mononuclear phagocytes. These cells were also infected by an actA mutant defective in cell-to-cell spreading. This suggests that Listeria are transported by DCs from PPs to the deep paracortical regions of draining MLNs and are then transmitted to other cell populations by mechanisms independent of ActA. Another pathway of dissemination to MLNs was identified, probably involving free Listeria and leading to the infection of ED3-positive mononuclear phagocytes in the subcapsular sinus and adjacent paracortical areas. This study provides evidence that DCs are major cellular targets of L. monocytogenes in PPs and that DCs may be involved in the early dissemination of this pathogen. DCs were not sites of active bacterial replication, making these cells ideal vectors of infection. [ABSTRACT FROM AUTHOR]

The present research study aims to improve the efficiency of photovoltaic systems applied to homes in isolated areas. This experimental study was carried using a prototype of a rural house, located at the Technological University of Peru - Arequipa, Peru. The photovoltaic solar system, connected to the prototype house, supplied its electric loads (TV, Blu-ray, radio, refrigerator, blender, heater, washing machine, fan, iron), which were programmed to be turned on and off using digital timers during a period of 3 months (March, April and May 2020). The measured parameters were the solar power, the consumed electrical power and the electrical power of what would be an auxiliary source of energy (electric generator, for example) in case the solar resource is unavailable. The results indicate that the photovoltaic solar system could store the unused solar energy to supply the nighttime electrical loads, ensuring, in this way, the autonomy of the energy system.

An experimental study was carried out to determine the production costs of ice slurry, using a saline solution with different fractions of ice, for “Perico” (Coryphaena Hippurus) artisanal fishing in the Peruvian sea. A 3-kW ice slurry generator, portable enough to fit in an artisanal boat, was used. The prototype was instrumented with sensors for temperature, density, and electrical parameters (voltage, current, power) measurement in order to determine the ice mass fraction and production costs. The results indicated that not only ice slurry ensures a higher cooling speed and less damage to the product, but also, its production costs are lower compared to flake ice.

An experimental study was carried out to determine the costs of freezing artisanally fished Perico (Coryphaena Hippurus) in Peru. A refrigeration chamber was equipped with electrical and temperature sensors to determine the thermal efficiency and thus calculate the costs of freezing the fish. The results indicate that it is possible to freeze and store fish to avoid speculation due to over production and thus improve the selling prices. In this way, it is possible to store the fish until the prices are attractive again so that fishermen sell their product at fair prices and progressively improve their quality of life.

Evidence for pleiotropic activation of virulence genes in Listeria monocytogenes is presented. A complementation study of a spontaneous prfA-deletion mutant and analysis of cassette and transposon insertion mutants showed that the gene prfA activates the transcription of four independent genes which code for a phosphatidyl-inositol-specific phospholipase C (gene plcA), listeriolysin O (gene hlyA), a metallo-protease (gene prtA) and a lecithinase (gene prtC). Transcription of prfA is not constitutive. During the growth phase, two peaks of prfA transcript accumulation were observed: the first was during exponential growth, and the second was at the beginning of the stationary phase, in addition, two prf4-specific transcripts of 2.2 kb and 1 kb are detected. Early in exponential growth, prfA is co-transcribed with plcA which lies upstream prfA, giving rise to the 2.2 kb plcA-prfA transcript, in late-exponential growth and at the beginning of the stationary phase, prfA transcripts of 1 kb are predominantly detected. Our results demonstrate that since prfA controls plcA transcription, it also regulates its own synthesis. [ABSTRACT FROM AUTHOR]

A thermoelectric cooling system supplied by photovoltaic solar energy was built and evaluated with different thermal loads. The thermoelectric cooling module consumes 70 W, it is supplied by a photovoltaic system of 90 W and 40 Ah battery. The voltage and electrical current in each component (panels, battery, and electric charge) has been measured. The tests were performed with different thermal loads placed in glass containers used for vaccines. To analyze the cooling and preservation process, the experiments were started at room temperature. The results show that the thermoelectric cooling system works for small thermal loads, and it could be applied to transport vaccines in isolated areas where people carry medicines in small containers that do not maintain the temperature necessary for the conservation of vaccines.

A reliable methodology for the dimensioning of photovoltaic systems is presented in this paper. This method generates technical-financial variables that aid in the choice of the most adequate photovoltaic power system for each project. The techniques that are usually used determine the size of PV power plants considering the monthly average of the solar energy potential of the month with the lowest solar radiation and the electricity to be supplied to satisfy the demand. These conventional techniques generate an uncertainty of at least 40 %, mainly due to the daily dispersion of the solar energy availability and of the electric load. The proposed methodology takes into account a region’s own photovoltaic energy potential and the detailed characteristics of the electric load, matching both with different PV power plants sizes, and analyzing the whole during a time period that guarantees the reliability of the results. The energy coupling is performed integrating the energy parameters (solar energy and electric load) in short time intervals (30 minutes maximum) to determine the supplied energy, the unsupplied energy demand and the unused solar energy. The daily integration of the three factors, using a dynamic simulation and performing a financial evaluation, allows for the identification of the most appropriate PV power plant size for every project. The results indicate that this methodology reduces the uncertainty of the solar power-electric load coupling from 40 % to 2.2 %, which allows a better definition of the financial variables that determine the most appropriate installed solar power for a photovoltaic project.

Abstract Background Mammal macrophages (MΦ) display a wide range of functions which contribute to surveying and maintaining tissue integrity. One such function is phagocytosis, a process known to be subverted by parasites like Leishmania (L). Indeed, the intracellular development of L. amazonensis amastigote relies on the biogenesis and dynamic remodelling of a phagolysosome, termed the parasitophorous vacuole, primarily within dermal MΦ. Results Using BALB/c mouse bone marrow-derived MΦ loaded or not with amastigotes, we analyzed the transcriptional signatures of MΦ 24 h later, when the amastigote population was growing. Total RNA from MΦ cultures were processed and hybridized onto Affymetrix Mouse430_2 GeneChips®, and some transcripts were also analyzed by Real-Time quantitative PCR (RTQPCR). A total of 1,248 probe-sets showed significant differential expression. Comparable fold-change values were obtained between the Affymetrix technology and the RTQPCR method. Ingenuity Pathway Analysis software® pinpointed the up-regulation of the sterol biosynthesis pathway (p-value = 1.31e-02) involving several genes (1.95 to 4.30 fold change values), and the modulation of various genes involved in polyamine synthesis and in pro/counter-inflammatory signalling. Conclusion Our findings suggest that the amastigote growth relies on early coordinated gene expression of the MΦ lipid and polyamine pathways. Moreover, these MΦ hosting multiplying L. amazonensis amastigotes display a transcriptional profile biased towards parasite-and host tissue-protective processes.

Parasites establish dynamic relationships with their hosts that allow their persistence . Leishmania spp. are unicellular parasites that have two hosts: a haematophageous insect, the sand fly, and a vertebrate. Both in animals and humans, absence of clinical lesions does not imply absence of infection. This phenomenon has major implications in epidemiology, preventive medicine, and pharmacology. Parasitic load determination in mammalian tissues or organs is currently performed by culture-based methods that are time consuming and require samples harbouring cultivable parasites. Recently, we developed a real-time PCR assay to quantify the parasitic burden of several Leishmania spp. based on detection of kinetoplastic DNA (kDNA). The efficacy of this real-time PCR assay was first evaluated in monitoring the fate of Leishmania major in C57Bl/6 mice following intradermal inoculation of the right ear pinna with low doses of infective metacyclics at 24 h, 96 h, and weekly for 7 weeks. Leishmania were established in the center of the inoculated pinna, to a lesser extent in the pinna border, and in the draining lymph node. The parasite was detected, but not quantified, in distant cutaneous sites (left ear pinna, thorax skin, tail base) and in the femoral bone marrow. Throughout the whole experiment, the parasite was detected in the glabrous tail base skin. We also investigated whether the parasites detected by our method were still viable or if we were also detecting DNA from dead parasites. Technical and biological constraints have been overcome by developing an in vitro model to monitor the persistence of Leishmania kDNA in cultured mouse macrophages after host leucocytes were exposed to L-leucine-methyl ester, a leishmanicidal molecule. The detection of kDNA by real-time PCR was correlated with the viability of the parasites in macrophages. These results show that laboratory mice (experimental host) or in vitro-grown mouse macrophages infected with Leishmania parasites can be considered useful systems in two areas. First, in pharmacology, preventive medicine and epidemiology, such a system would allow pharmacological evaluation of Leishmania-targeted drugs or vaccines to a broader extent than merely monitoring the reduction of the lesion or the prevention of lesion onset. A similar system could be developed in other animal species, particularly the dog, in order to detect asymptomatic carriage at the borders or in quarantines, or to investigate the real prevalence of Leishmania spp. The growing importance of Leishmania infantum-related disorders in humans makes such a method very interesting. A second use for this experimental system is the investigation of the prompt and renewed interactions that Leishmania parasites establish within their mammalian hosts. Establishment of a system to quantify the parasitic burden of Leishmania spp. is the perspective of this preliminary research. Recently published data show that the apparent lack of symptoms hides complex mechanisms involving very different factors such as keratinocytes, epidermal and dermal leucocytes, the extracellular matrix, and sand fly saliva. Funding: Institut Pasteur, Centre National de la Recherche Scientifique. [ABSTRACT FROM AUTHOR]

To attempt resolving this issue accurately, it was necessary to anchor our experimental approaches in the observations and pioneering work of our predecessors, notably Alphonse Laveran, Louis Parrot, Edmond and Étienne Sergent. The latter, among other things, had identified as natural hosts of leishmaniasis, rodent populations with which hematophagous telmophagous sand fly populations cohabited closely.When human populations emerged in these natural ecosystems, after the sedentarization of Homo sapiens, more or less important disturbances would have led to a transition of sand fly hematophagy, from zoophilia, to zoo-anthropophilia and anthropophilia.The creation of infrastructures that allow the breeding and integration into experimental groups of both holobiont sand flies and holobiont laboratory rodents (rats, mice, hamsters, etc.) remains crucial. With such infrastructures, it becomes possible to grasp and characterize the multilateral dynamic processes - mostly clinically silent - that account for the biogenesis of tissue and/or cellular niches protecting populations of Leishmania developmental morphotypes, including those ensuring host-to-host transmission, albeit in small numbers., (Copyright © 2023 SFMTSI.)

Leishmania parasites are the causative agents of human leishmaniases. They infect professional phagocytes of their mammalian hosts, including dendritic cells (DCs) that are essential for the initiation of adaptive immune responses. These immune functions strictly depend on the DC's capacity to differentiate from immature, antigen-capturing cells to mature, antigen-presenting cells-a process accompanied by profound changes in cellular phenotype and expression profile. Only little is known on how intracellular Leishmania affects this important process and DC transcriptional regulation. Here, we investigate these important open questions analyzing phenotypic, cytokine profile and transcriptomic changes in murine, immature bone marrow-derived DCs (iBMDCs) infected with antibody-opsonized and non-opsonized Leishmania amazonensis ( L.am ) amastigotes. DCs infected by non-opsonized amastigotes remained phenotypically immature whereas those infected by opsonized parasites displayed a semi-mature phenotype. The low frequency of infected DCs in culture led us to use Ds Red2-transgenic parasites allowing for the enrichment of infected BMDCs by FACS. Sorted infected DCs were then subjected to transcriptomic analyses using Affymetrix GeneChip technology. Independent of parasite opsonization, Leishmania infection induced expression of genes related to key DC processes involved in MHC Class I-restricted antigen presentation and alternative NF-κB activation. DCs infected by non-opsonized parasites maintained an immature phenotype and showed a small but significant down-regulation of gene expression related to pro-inflammatory TLR signaling, the canonical NF-kB pathway and the NLRP3 inflammasome. This transcriptomic profile was further enhanced in DCs infected with opsonized parasites that displayed a semi-mature phenotype despite absence of inflammasome activation. This paradoxical DC phenotype represents a Leishmania -specific signature, which to our knowledge has not been observed with other opsonized infectious agents. In conclusion, systems-analyses of our transcriptomics data uncovered important and previously unappreciated changes in the DC transcription factor landscape, thus revealing a novel Leishmania immune subversion strategy directly acting on transcriptional control of gene expression. Our data raise important questions on the dynamic and reciprocal interplay between trans -acting and epigenetic regulators in establishing permissive conditions for intracellular Leishmania infection and polarization of the immune response., (Copyright © 2020 Lecoeur, Rosazza, Kokou, Varet, Coppée, Lari, Commère, Weil, Meng, Milon, Späth and Prina.)

Aberrant macrophage activation during intracellular infection generates immunopathologies that can cause severe human morbidity. A better understanding of immune subversion strategies and macrophage phenotypic and functional responses is necessary to design host-directed intervention strategies. Here, we uncover a fine-tuned transcriptional response that is induced in primary and lesional macrophages infected by the parasite Leishmania amazonensis and dampens NF-κB and NLRP3 inflammasome activation. Subversion is amastigote-specific and characterized by a decreased expression of activating and increased expression of de-activating components of these pro-inflammatory pathways, thus revealing a regulatory dichotomy that abrogates the anti-microbial response. Changes in transcript abundance correlate with histone H3K9/14 hypoacetylation and H3K4 hypo-trimethylation in infected primary and lesional macrophages at promoters of NF-κB-related, pro-inflammatory genes. Our results reveal a Leishmania immune subversion strategy targeting host cell epigenetic regulation to establish conditions beneficial for parasite survival and open avenues for host-directed, anti-microbial drug discovery., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

Intracellular protozoans co-evolved with their mammalian host cells a range of strategies to cope with the composite and dynamic cell surface features they encounter during migration and infection. Therefore, these single-celled eukaryotic parasites represent a fascinating source of living probes for precisely capturing the dynamic coupling between the membrane and contractile cortex components of the cell surface. Such biomechanical changes drive a constant re-sculpting of the host cell surface, enabling rapid adjustments that contribute to cellular homeostasis. As emphasized in this review, through the design of specific molecular devices and stratagems to interfere with the biomechanics of the mammalian cell surface these parasitic microbes escape from dangerous or unfavourable microenvironments by breaching host cell membranes, directing the membrane repair machinery to wounded membrane areas, or minimizing membrane assault using discretion and speed when invading host cells for sustained residence., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The current paradigm in the pathogenesis of several hemolytic red blood cell disorders is that reduced cellular deformability is a key determinant of splenic sequestration of affected red cells. Three distinct features regulate cellular deformability: membrane deformability, surface area-to-volume ratio (cell sphericity), and cytoplasmic viscosity. By perfusing normal human spleens ex vivo, we had previously showed that red cells with increased sphericity are rapidly sequestered by the spleen. Here, we assessed the retention kinetics of red cells with decreased membrane deformability but without marked shape changes. A controlled decrease in membrane deformability (increased membrane rigidity) was induced by treating normal red cells with increasing concentrations of diamide. Following perfusion, diamide-treated red blood cells (RBCs) were rapidly retained in the spleen with a mean clearance half-time of 5.9 minutes (range, 4.0-13.0). Splenic clearance correlated positively with increased membrane rigidity ( r = 0.93; P < .0001). To determine to what extent this increased retention was related to mechanical blockade in the spleen, diamide-treated red cells were filtered through microsphere layers that mimic the mechanical sensing of red cells by the spleen. Diamide-treated red cells were retained in the microsphilters (median, 7.5%; range, 0%-38.6%), although to a lesser extent compared with the spleen (median, 44.1%; range, 7.3%-64.0%; P < .0001). Taken together, these results have implications for understanding the sensitivity of the human spleen to sequester red cells with altered cellular deformability due to various cellular alterations and for explaining clinical heterogeneity of RBC membrane disorders., (© 2018 by The American Society of Hematology.)

A very substantial progress has been made in our understanding of infectious diseases caused by invasive bacteria. Under their planktonic forms, bacteria transiently reside in the otherwise sterile mammal body tissues, as the physiological inflammation insures both their clearance and repair of any tissue damage. Yet, the bacteria prone to experience planktonic to biofilm developmental transition still need to be studied. Of note, sessile bacteria not only persist but also concur preventing the effectors and regulators of the physiological inflammation to operate. Thus, it is urgent to design biologically sound experimental approaches aimed to extract, at the earliest stage, immune signatures of mono-bacteria planktonic to biofilm developmental transition in vivo and ex vivo . Indeed, the transition is often the first event to which succeeds the "chronicization" process whereby classical bacteria-targeting therapies are no more efficacious. An in vivo model of micro-injection of Staphylococcus aureus planktonic or biofilm cells in the ear pinna dermis of laboratory transgenic mice with fluorescent immune cells is proposed. It allows visualizing, in real time, the range of the early interactions between the S. aureus and myeloid cell subsets- the resident macrophages and dendritic cells, the recruited neutrophil granulocytes/polymorphonuclear neutrophils, monocytes otherwise known to differentiate as macrophages or dendritic cells. One main objective is to extract contrasting immune signatures of the modulation of the physiological inflammation with respect to the two bacterial lifestyles.

Leishmania/L. major was identified as the etiological agent of human localized cutaneous leishmaniasis. L. major metacyclic promastigotes/MP - the infectious form transmitted by sand flies - were enriched from axenically-derived cultures and inoculated into the dermis of mice (10(3) or 10(4) luciferase-expressing L. major MP inoculated into the C57BL/6 mouse ear pinna). Quantitative readout assays were then combined with imaging of this L. major-hosting skin site and established i) that a specific period of time - depending upon the L. major load used for the inoculation - is required for the L. major-hosting ear pinna to be continuously populated by a balanced population of functional regulatory and effector T lymphocytes, and that ii) this balance coincides with persisting low numbers of amastigotes in more or less rapidly healing skin. This approach also established that, whatever the MP inoculum load delivered to the primary site, the immune processes that reduce the L. major amastigote population also account for concomitant immunity, namely remodelling of the secondary site - where 10(4) MP were delivered - as a clinically silent niche hosting a small L. major population., (© 2013. Published by Elsevier Ireland Ltd. All rights reserved.)

The mechanisms underlying reduced red blood cell (RBC) deformability during Plasmodium falciparum (Pf) malaria remain poorly understood. Here, we explore the possible involvement of the L-arginine and nitric oxide (NO) pathway on RBC deformability in Pf-infected patients and parasite cultures. RBC deformability was reduced during the acute attack (day0) and returned to normal values upon convalescence (day28). Day0 values correlated with plasma L-arginine levels (r = 0.69; p = 0.01) and weakly with parasitemia (r = -0.38; p = 0.006). In vitro, day0 patient's plasma incubated with ring-stage cultures at 41°C reduced RBC deformability, and this effect correlated strongly with plasma L-arginine levels (r = 0.89; p < 0.0001). Moreover, addition of exogenous L-arginine to the cultures increased deformability of both Pf-free and trophozoite-harboring RBCs. NO synthase activity, evidenced in Pf-infected RBCs, induced L-arginine-dependent NO production. These data show that hypoargininemia during P. falciparum malaria may altogether impair NO production and reduce RBC deformability, particularly at febrile temperature.

Background: After loading with live Leishmania (L) amazonensis amastigotes, mouse myeloid dendritic leucocytes/DLs are known to undergo reprogramming of their immune functions. In the study reported here, we investigated whether the presence of live L. amazonensis amastigotes in mouse bone marrow-derived DLs is able to trigger re-programming of DL lipid, and particularly neutral lipid metabolism., Methodology/principal Findings: Affymetrix-based transcriptional profiles were determined in C57BL/6 and DBA/2 mouse bone marrow-derived DLs that had been sorted from cultures exposed or not to live L. amazonensis amastigotes. This showed that live amastigote-hosting DLs exhibited a coordinated increase in: (i) long-chain fatty acids (LCFA) and cholesterol uptake/transport, (ii) LCFA and cholesterol (re)-esterification to triacyl-sn-glycerol (TAG) and cholesteryl esters (CE), respectively. As these neutral lipids are known to make up the lipid body (LB) core, oleic acid was added to DL cultures and LB accumulation was compared in live amastigote-hosting versus amastigote-free DLs by epi-fluorescence and transmission electron microscopy. This showed that LBs were both significantly larger and more numerous in live amastigote-hosting mouse dendritic leucocytes. Moreover, many of the larger LB showed intimate contact with the membrane of the parasitophorous vacuoles hosting the live L. amazonensis amastigotes., Conclusions/significance: As leucocyte LBs are known to be more than simple neutral lipid repositories, we set about addressing two related questions. Could LBs provide lipids to live amastigotes hosted within the DL parasitophorous vacuole and also deliver? Could LBs impact either directly or indirectly on the persistence of L. amazonensis amastigotes in rodent skin?