7,068 research outputs found

    Zinc as a potential therapy for Burkitt’s lymphoma

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    Burkitts lymphoma (BL) is a form of non-Hodgkin lymphoma (NHL) that arises from germinal center B cells. BL is characterized by translocations of the C-MYC oncogene to immunoglobulin light and heavy chain loci resulting in its constitutive deregulated expression. BL shows a rapid and aggressive growth pattern. There are three different forms of BL; sporadic BL (sBL), immunodeficiency-associated BL and endemic BL (eBL) which accounts for ~50% of all paediatric cancers in Sub-Saharan Africa. Due to financial restrictions, treatment and supportive care options are limited resulting in poorer outcomes in low - middle income countries (LMICs). Thus, there is a need to develop new affordable effective low toxicity treatments for eBL. Prior to this study, a panel of BL cell lines were tested against an in-house custom drug repurposing library developed in our lab (FMC Library) that contains ~100 approved and commonly used drug. This screen identified the nutritional supplement zinc acetate as an effective anti-BL candidate. Dose response studies showed that all BL cell lines tested had little/no response to zinc at 50 μM whereas 100 μM zinc killed all BL cell lines. In contrast, 100 μM zinc acetate induced no killing against a panel of non-BL cell lines including acute myeloid leukaemia (AML) which is a non BL cell tumour, diffuse large B cell lymphoma (DLBCL) which represent a B cell lymphoma that arise from germinal centre B cells and BV infected lymphoblastoid cell lines (LCL) as a control cells. The latter were used as karyotypically normal B cell controls. Cell death in BL cells was associated with positive flow cytometry staining for propidium iodide and annexin V and activation of caspase 3 and 9 (western blotting) indicating cell death by apoptosis. The proto-oncogene C-MYC is mutated or deregulated in >50% of cancers. In BL, deregulated expression occurs as a consequence of translocation of C-MYC on chromosome 8q24 to either the immunoglobulin heavy chain enhancer region on 14q32 (85% of cases) or the immunoglobulin kappa light chain or lambda loci on 2p12 or 22q11, respectively (15% of cases). Thus, the effect of zinc on C-MYC protein levels were studied. Western blot analysis showed that 100 μM zinc was able to reduce C-MYC protein levels rapidly and sustainably in BL cell lines whereas no change in C-MYC protein levels was observed in non-BL cell lines. Zinc-induced reduction of C-MYC protein levels was time-dependent, reducing by approximately 20% after 6 hours with little/no protein detectable after 24 hours. C-MYC protein levels were not reduced following treatment with 50 μM zinc. Quantitative real time PCR (qRT-PCR) also showed a rapid reduction in C-MYC mRNA levels in BL cell lines after 6 hours exposure to 100 μM but not upon exposure to 50μM. Again, no reduction in C-MYC mRNA levels was seen in non-BL cell lines. Translocations of other genes to the immunoglobulin loci occur in other forms of NHL. The DLBCL cell line SU-DHL-4 has a t(14;18) translocation resulting in deregulated expression of the protooncogene BCL2. Western blotting showed no decrease in BCL-2 protein levels in SU-DHL-4 in response to either 100 μM or 50 μM zinc acetate after 6 or 24 hours indicating a selectivity of zinc action against C-MYC protein in BL cells. To further investigate the role of altered C-MYC expression in zinc-mediated killing of BL cells, the eBL cell lines Raji and Namalwa were stably transfected with C-MYC using a piggyBac transposon system that allows gene expression under a constitutively active promoter. However, overexpression of C-MYC from an alternative promoter did not rescue BL cells from killing by 100μM zinc. Although western blotting showed that C-MYC protein levels were protected after 6 hours, protein reduction and loss of viability was again observed after 24 hours indicating that loss of C-MYC is important in zinc-mediated killing of BL cells. In a second approach to rescue C-MYC expression, the proteasome inhibitor Bortezomib was used to inhibit C-MYC protein degradation via the ubiquitin-proteasome system (UPS). Whilst increases were observed in overall ubiquitinated proteins indicating bortezomib was working, western blotting and flow cytometry showed no rescue of C-MYC protein levels. Furthermore, bortezomib did not rescue cells from zinc-mediated killing after 24 hours. In conclusion, findings from this study have identified that 100 mM zinc is effective at killing BL cell lines selectively, and that this killing is associated with activation of apoptotic markers. Treatment with zinc resulted in a rapid and sustained reduction in C-MYC mRNA and protein levels that could not be rescued through constitutive overexpression or the use of proteasome inhibitors. Given that zinc deficiency is common in sub-Saharan Africa and that zinc supplementation is safely used to treat diarrhoeal episodes in children, the studies proposed here indicate that zinc may safely be used as an adjunctive therapy to target C-MYC in BL

    Ruthenium metallotherapeutics: a targeted approach to combatting multidrug resistant pathogens

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    The discovery of antibiotics revolutionised healthcare practice. However due to overuse, inappropriate use, widespread prophylaxis therapy and the lack of new developments, the threat of antimicrobial resistance is now a major global threat to health. By 2050, it is estimated that mortality due to antimicrobial resistant infections will exceed 10 million people per annum, superseding cancer as the leading cause of global mortality. The use of drug repurposing to identify potential therapies which combat antimicrobial resistance is one potential solution. Metals have been used as antimicrobial agents throughout the history of medicine for a broad range of applications, including the use of Silver as an antimicrobial agent which dates back to antiquity. More recently, Ruthenium metallotherapeutic complexes have been shown to exhibit highly active antimicrobial properties by targeting a range of bacterial species, and in contrast to traditional antibiotics, these compounds are thought to elicit antibacterial activity at multiple sites within the bacterial cell, which may reduce the possibility of resistance evolution. This study aimed to evaluate the antimicrobial activity of a series of Ruthenium metallotherapeutic complexes against multidrug-resistant bacterial pathogens, with a focus on use within wound care applications. Antimicrobial susceptibility assays identified two lead candidates, Hexaammineruthenium (III) chloride and [Chlorido(η6-p-cymene)(N-(4-chlorophenyl)pyridine-2-carbothioamide) ruthenium (II)] chloride which demonstrated activity against Pseudomonas aeruginosa and Staphylococcus aureus respectively with MIC values ranging between 4 μg mL-1 and 16 μg mL-1. Furthermore, Hexaammineruthenium (III) chloride demonstrated antibiofilm activity in both a time and concentration-dependent manner. Synergy studies combining lead complexes with antibiotics demonstrated the potential for use as resistance breakers. Subsequent in vitro infection modelling using scratch assays with skin cell lines, coupled with a 3D full thickness skin wound infection model was used to determine potential applied applications of Hexaammineruthenium (III) chloride for use as topical antimicrobial agent against P. aeruginosa infections. Antimicrobial mechanistic studies demonstrated that Hexaammineruthenium (III) chloride targeted the bacterial cell ultrastructure of P. aeruginosa strain PAO1 as cell perturbations were observed when treated cells were analysed by scanning electron microscopy. Furthermore, exposure of P. aeruginosa PAO1 to Hexaammineruthenium (III) chloride also resulted in a concentration dependent membrane depolarisation, which further supported the antimicrobial mechanistic role. Finally, global changes in gene expression following exposure of P. aeruginosa strain PAO1 to Hexaammineruthenium (III) chloride were explored by RNA sequencing. Genes involved in ribosome function, cofactor biosynthesis and membrane fusion were downregulated, which provided a further insight into the wider mechanisms of antibacterial activity. The research conducted in the present study indicated the potential use of Hexaammineruthenium (III) chloride (and derivatives) as a potential treatment option for chronic wounds infected with P. aeruginosa, which could be applied as either a direct treatment or used within antimicrobial wound care applications

    Unravelling the Impact of Human Papillomavirus (HPV): A Comprehensive Exploration of its Role in Cancer Progression and Global Health Challenges

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    HPV represents a large group of double stranded DNA viruses that are highly involved with different types of human cancers. This synopsis describes the complexities surrounding HPV virology, classifications, and genomic variation, especially focusing on high-risk strains such as HPV16 and HPV18, the main causative factors for cervical cancers. The International Committee on Taxonomy of Viruses specifies more than 200 HPV types each associated with a respective disease and indicated in Table 1. HPV spread is mostly due to direct skin-to-skin contact between individuals’ sex organs causing infections on the mucous membrane and keratinized epithelial cells. Although majority of the infections are asymptomatic, some chronic HRHPV infections may progress into cancers because of oncoproteins E6 and E7. The high-risk variants of HPV lead to cervical, anal, and oropharyngeal cancers whereas the low-risk types cause harmless genital warts. While integrating HPV DNA into the host genome, orchestrated by oncoproteins E6 and E7 disrupts the cell regulatory mechanism; this leads to abnormal control over cell multiplication–one of the major elements of the process that develops to HPV induced cancer. A classic case is cervical cancer that has been extensively investigated as one of the highly documented HPV associated malignancies. Pap smears and HPV DNA tests are among the screening means that lower the incidents and deaths associated with cervical cancers. HPV-associated cancers of the head and neck, anus, penis, vulva, and vagina all show a characteristic profile in terms of the pathogen aetiology and risks involved. HPV-related head and neck cancers affect non-smokers and show good response to standard therapies. HPV poses increased anal cancer risk for immunocompromised individuals highlighting the complexity of interdependence of immunity and cancer development. Penile cancer results from poor hygiene and non-circumcision. Vulvar and virginal cancer mostly affects women, and the risk factors involve HPV infection and smoking. Therefore, various types of multidisciplinary approach that may include surgeries, radiotherapy, and chemotherapy are necessary to ensure proper treatment. Certain cancers are strongly associated with some high-risk HPV genotypes, such as HPV-16 and HPV-18; thus, vaccination is important. HPV infection outcomes are determined by the immune response as well as clearance of HPV infection. Screening and immunological understanding for early detection of HPV related health risks is fundamental. However, this encompassing review highlights the multi-dimensional impact of HPV encompassing virology of HPV, cancer specific presentation of HPV and control including prevention of HPV infection, screening, and research on cancer attributable by HPV and strategies towards mitigation of this global health problem

    Modelling spatiotemporal patterns of visceral leishmaniasis incidence in two endemic states in India using environment, bioclimatic and demographic data, 2013-2022.

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    BACKGROUND: As of 2021, the National Kala-azar Elimination Programme (NKAEP) in India has achieved visceral leishmaniasis (VL) elimination (93% and 99% coverage probability (proportion of observations falling inside 95% Bayesian credible interval for the predicted number of VL cases per month) during the training and testing periods. PIT (probability integral transform) histograms confirmed consistency between prediction and observation for the test period. Forecasting for 2021-2023 showed that the annual VL incidence is likely to exceed elimination threshold in 16-18 blocks in 4 districts of Jharkhand and 33-38 blocks in 10 districts of Bihar. The risk of VL in non-endemic neighbouring blocks of both Bihar and Jharkhand are less than 0.5 during the training and test periods, and for 2021-2023, the probability that the risk greater than 1 is negligible (P<0.1). Fitted model showed that VL occurrence was positively associated with mean temperature, minimum temperature, enhanced vegetation index, precipitation, and isothermality, and negatively with maximum temperature, land surface temperature, soil moisture and population density. CONCLUSIONS/SIGNIFICANCE: The spatiotemporal model incorporating environmental, bioclimatic, and demographic factors demonstrated that the KAMIS database of the national programmme can be used for block level predictions of long-term spatial and temporal trends in VL incidence and risk of outbreak / resurgence in endemic and non-endemic settings. The database integrated with the modelling framework and a dashboard facility can facilitate such analysis and predictions. This could aid the programme to monitor progress of VL elimination at least one-year ahead, assess risk of resurgence or outbreak in post-elimination settings, and implement timely and targeted interventions or preventive measures so that the NKAEP meet the target of achieving elimination by 2030

    Plasma-derived exosomal miRNA as potential biomarker for diagnosis and prognosis of vector-borne diseases: A review

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    Early disease diagnosis is critical for better management and treatment outcome of patients. Therefore, diagnostic methods should ideally be accurate, consistent, easy to perform at low cost and preferably non-invasive. In recent years, various biomarkers have been studied for the detection of cardiovascular diseases, cerebrovascular diseases, infectious diseases, diabetes mellitus and malignancies. Exosomal microRNA (miRNA) are small non-coding RNA molecules that influence gene expression after transcription. Previous studies have shown that these types of miRNAs can potentially be used as biomarkers for cancers of the breast and colon, as well as diffuse large B-cell lymphoma. It may also be used to indicate viral and bacterial infections, such as the human immunodeficiency virus (HIV), tuberculosis and hepatitis. However, its use in the diagnosis of vector-borne diseases is rather limited. Therefore, this review aims to introduce several miRNAs derived from exosomal plasma that may potentially serve as a disease biomarker due to the body’s immune response, with special focus on the early detection of vector-borne diseases

    Effective immuno-therapeutic treatment of Canine Leishmaniasis.

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    BackgroundCanine Leishmaniasis (CanL) caused by the L. infantum species is one of the biggest threats to the health of the South American canine population. Chemotherapeutics currently used for the treatment of CanL fail to induce a total parasite clearance while inducing numerous side effects. As CanL is an immunomodulated disease, the use of immuno-treatments should strengthen the deficient immune response of infected dogs. In this study, we evaluated a nasally administered immunotherapy in dogs naturally infected with L. infantum (stage 2), with both visceral and cutaneous manifestations. Noteworthy, some of them were also infected by other parasites (E. canis, D. immitis, A. platys), what worsen their chance of survival.Methodology/principal findingsThe treatment was based on 2 intranasal (IN.) administrations of a killed L. infantum parasite loaded into maltodextrin nanoparticles, which treatment was compared with the classical oral administration of Miltefosine (2 mg/kg) for 28 days, as well as a combination of these 2 treatments. The results showed that two IN administrations significantly reduced the serology, and were at least as efficient as the chemotherapy to reduce the skin and bone marrow parasite burden, as well as clinical scores, and that unlike Miltefosine treatments, this nasally administered nanoparticle vaccine was without side effects.ConclusionsThese results confirm the feasibility of a simple therapeutic immuno-treatment against L. infantum infected dogs, which is a promising tool for future developments


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    O Programa de Pós-Graduação stricto sensu em “Saúde e Envelhecimento”, iniciou suas atividades em 2011, com conceito três da CAPES, evoluindo, em 2018, para. Conceito quatro. A análise da produção bibliográfica de um programa de pós-graduação é fundamental no sentido de traçar ações, visando sua melhor qualificação. Neste contexto, o objetivo deste estudo foi analisar a produção científica oriunda das dissertações concluídas no referido programa. A busca foi realizada consultando o Currículo Lattes de docentes e discentes da pós-graduação, utilizando um formulário padrão para extração dos dados. No período analisado, foram realizadas 114 defesas de dissertações, que resultaram em 72 publicações científicas, média de 9,12 publicações/ano. Os dados métricos puderam ser obtidos de 56 publicações, o índice h5, obtido de 35 publicações, variou de 1 a 125, o fator de impacto variou entre 0,309 e 3,759, e o Qualis CAPES, obtido de 44 publicações, variou de A1 até B4. A média de citações por artigo foi de 1,94, entre 42 publicações analisadas. Dentre os 53 periódicos nos quais foram publicados os trabalhos, 36 (67,9%) são nacionais e 17 (32,1%) internacionais, adotando, a maioria, a revisão por pares. Os resultados mostram que a maioria da produção científica é publicada em periódicos nacionais, em média 1,5 anos após a defesa da dissertação, e consiste em pesquisa do tipo observacional. A implementação do curso de doutorado seria uma das recomendações possíveis, com o potencial de melhorar a produção científica tanto no sentido quantitativo, como no qualitativo

    Effect of chokeberry fruit water extract on the immune system in mouse models of infection and melanoma

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    Aronija (lat. Aronia melanocarpa), voće karakteristično po tamnim bobicama oporog ukusa, sadrži mnoštvo fenolnih jedinjenja zaslužnih za njena biološka svojstva. Vodeni ekstrakt ploda aronije (VEPA) pokazao je proinflamacijsko dejstvo. In vitro primena povećala je fagoctinu sposobnost makrofaga i stimulisala produkciju azot-monoksida iz dendritskih ćelija, kao i diferencijaciju proinflamacijskih CD4+ T limfocita. In vivo, oralni tretman zdravih miševa doveo je do promene distribucije ćelija imunskog sistema u crevu i povećane produkcije IFN-γ u slezini. Efekat VEPA na imunski sistem ispitan je u mišjim modelima infekcije unutarćelijskom bakterijom Listeria monocytogenes i melanoma, indukovanog subkutanim injeciranjem B16 ćelija. Pretretman VEPA ublažava kliničku sliku i doprinosi eliminaciji infekcije tako što na mestu inicijacije infekcije – u Pejerovim pločama i u ciljnom tkivu – slezini, povećava zastupljenost CD8+ T limfocita i makrofaga, pri čemu su efektorska svojstva makrofaga naročito stimulisana. U modelu melanoma pretretman VEPA smanjio je incidencu bolesti i zapreminu tumora, istovremeno povećavajući infiltraciju ćelija imunskog sistema u tumor. Zastupljenost NK ćelija, CD4+ i CD8+ T limfocita unutar tumora povećana je usled pretretmana VEPA, kao i ekspresija IFN-γ u ovim ćelijama, dok je zastupljenost supresivnih ćelija smanjena. Produkcija IFN-γ povećana je i u mezenteričnim limfnim čvorovima, slezini i serumu pretretiranih životinja. Splenociti ove grupe životinja pokazali su veću citotoksičnost prema ćelijama melanoma, zavisnu od IFN-γ. Izostanak direktnog uticaja na B16 ćelije dodatno ukazuje na imunomodulacijska svojstva VEPA. Ovi rezultati ukazuju na potencijal primene aronije u prevenciji stanja i bolesti u kojima je neophodna stimulacija proinflamacijskog imunskog odgovora.Chokeberry (Aronia melanocarpa), fruit with black berries that leave an astringent mouthfeel after consumption, is rich in polyphenols responsible for its bioactive properties. Chokeberry extract (VEPA) showed profound in vitro and in vivo pro-inflammatory effects. When applied in vitro, VEPA stimulated phagocytic ability of macrophages and NO production from dendritic cells, as well as differentiation of pro-inflammatory CD4+ T cells. In vivo oral treatment of healthy mice changed the distribution of immune cells within the gut and increased production of IFN-γ in the spleen. In the mouse model of infection with intracellular bacteria Listeria monocytogenes VEPA accelerated eradication of infection and improved their general appearance. Also, VEPA pretreatment increased proportions of macrophages and CD8+ T cells both in the gut and the spleen of infected mice and mainly affected effector functions of macrophages. In the mouse model of melanoma, induced by subcutaneous injection of B16 cells, VEPA delayed melanoma appearance, decreased tumor volume and increased infiltration of immune cells in the tumor. Proportion of NK cells, CD4+ and CD8+ T cells within the tumor was increased, as well as the expression of IFN-γ within these cells, with downregulated frequency of cells that suppress the immune cells. Additionally, the production of IFN-γ was enhanced in the mesenteric lymph nodes, spleen and the serum of pretreated animals. Splenocytes from these animals showed enhanced cytotoxicity towards melanoma cells, dependent on IFN-γ. These results point to the applicative potential of VEPA in the prevention of different states and diseases where an enhanced pro-inflammatory response is needed