Acinetobacter baumannii (named in honor of the American bacteriologists Paul and Linda Baumann) is a Gram-negative, multidrug-resistant (MDR) pathogen that causes nosocomial infections, especially in intensive care units (ICUs) and immunocompromised patients with central venous catheters. A. baumannii has developed a broad spectrum of antimicrobial resistance, associated with a higher mortality rate among infected patients compared with other non-baumannii species. In terms of clinical impact, resistant strains are associated with increases in both in-hospital length of stay and mortality. A. baumannii can cause a variety of infections; most involve the respiratory tract, especially ventilator-associated pneumonia, but bacteremia and skin wound infections have also been reported, the latter of which has been prominently observed in the context of war-related trauma. Cases of meningitis associated with A. baumannii have been documented. The most common risk factor for the acquisition of MDR A baumannii is previous antibiotic use, following by mechanical ventilation, length of ICU/hospital stay, severity of illness, and use of medical devices. Current efforts focus on addressing all the antimicrobial resistance mechanisms described in A. baumannii, with the objective of identifying the most promising therapeutic scheme. Bacteriophage- and artilysin-based therapeutic approaches have been described as effective, but further research into their clinical use is required

To assess the possibility of using the antimalarial drug artemisinin and its synthetic derivatives as antineoplastic drugs. A Pubmed and Google Scholar (1983–2018) search was performed using the terms artemisinin, cancer, artesunate and Artemisia annua. Case reports and original research articles, review articles, and clinical trials in both humans and animals were evaluated. Both in vitro and in vivo clinical trials and case reports have shown promising activity of the artemisinin drug derivatives in treating certain types of cancer. However, the reported articles are few, and therefore not statistically significant. The minimal toxicity shown in clinical trials and case reports, along with the selective cytotoxic activity of the compounds, make them possible cancer therapies due to the emerging evidence of the drug’s effectiveness.

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There are many types of cell death, each involving multiple and complex molecular events. Cell death can occur accidentally when exposed to extreme physical, chemical, or mechanical conditions, or it can also be regulated, which involves a genetically coded complex machinery to carry out the process. Apoptosis is an example of the latter. Apoptotic cell death can be triggered through different intracellular signalling pathways that lead to morphological changes and eventually cell death. This is a normal and biological process carried out during maturation, remodelling, growth, and development in tissues. To maintain tissue homeostasis, regulatory, and inhibitory mechanisms must control apoptosis. Paradoxically, these same pathways are utilized during infection by distinct intracellular microorganisms to evade recognition by the immune system and therefore survive, reproduce and develop. In cancer, neoplastic cells inhibit apoptosis, thus allowing their survival and increasing their capability to invade different tissues and organs. The purpose of this work is to review the generalities of the molecular mechanisms and signalling pathways involved in apoptosis induction and inhibition. Additionally, we compile the current evidence of apoptosis modulation during cancer and Leishmania infection as a model of apoptosis regulation by an intracellular microorganism.

Dendritic cells (DCs) are a type of cells derived from bone marrow that represent 1% or less of the total hematopoietic cells of any lymphoid organ or of the total cell count of the blood or epithelia. Dendritic cells comprise a heterogeneous population of cells localized in different tissues where they act as sentinels continuously capturing antigens to present them to T cells. Dendritic cells are uniquely capable of attracting and activating naïve CD4+ and CD8+ T cells to initiate and modulate primary immune responses. They have the ability to coordinate tolerance or immunity depending on their activation status, which is why they are also considered as the orchestrating cells of the immune response. The purpose of this review is to provide a general overview of the current knowledge on ontogeny and subsets of human dendritic cells as well as their function and different biological roles.

Among the most frequent nosocomial infections associated with polyresistant bacteria and with a worse prognosis, are those produced by Pseudomonas aeruginosa. This bacterium has a high capacity to adapt to adverse conditions such as pH and osmolarity of urine. Pseudomonas aeruginosa is one of the main pathogens involved in nosocomial infections and immunosuppressed patients. This bacterium is considered an opportunistic infectious agent that has diverse mechanisms of pathogenicity, as well as resistance to antimicrobials, which contributes to the difficulty in the treatment of these infections. In the present bibliographic review, the taxonomy, pathogenicity mechanisms and resistance genes of P. aeruginosa are analyzed. Likewise, the micro-environmental factors of the urinary infection produced by this bacterium are approached, making an approach to the understanding of the pathophysiological bases of this infection.

Leishmania mexicana is the causal agent of cutaneous leishmaniasis in Mexico. Dendritic cells (DC) are one of the host cells of Leishmania parasites. Intracellular microorganisms inhibit host cell apoptosis as a strategy to ensure their survival in infected cells. We have previously shown that Leishmania mexicana promastigotes and amastigotes inhibit camptothecin-induced apoptosis of monocyte-derived dendritic cells (moDC), but the mechanisms underlying the inhibition of apoptosis of DC by Leishmania have not been established. MAP kinases and PI3K participate in the process of apoptosis and are modulated by different species of Leishmania. As shown in this study, the infection of moDC with L. mexicana amastigotes diminished significantly the phosphorylation of the MAP kinases p38 and JNK. The inhibition of both kinases diminished significantly DNA fragmentation in moDC stimulated with camptothecin. On the other hand, L. mexicana amastigotes were able to activate the anti-apoptotic pathways PI3K and AKT. Our results indicate that L. mexicana amastigotes have the capacity to diminish MAP kinases activation and activate PI3K and AKT, which is probably one of the strategies employed by L. mexicana amastigotes to inhibit apoptosis in the infected moDC.

Introduction: Chagas disease (CD) is caused by Trypanosoma cruzi. When acquired, the disease develops in stages. For diagnosis, laboratory confirmation is required, and an extensive assessment of the patient’s health should be performed. Treatment consists of the administration of trypanocidal drugs, which may cause severe adverse effects. The objective of our systematic review was to analyze data contained in the CD published case reports to understand the challenges that patients and clinicians face worldwide. Materials and methods: We performed a systematic review following the PRISMA guidance. PubMed database was explored using the terms ‘American trypanosomiasis’ or ‘Chagas disease’. Results were limited to human case reports written in English or Spanish. A total of 258 reports (322 patients) were included in the analysis. Metadata was obtained from each article. Following this, it was analyzed to obtain descriptive measures. Results: From the sample, 56.2% were males and 43.8% were females. Most cases were from endemic countries (85.4%). The most common clinical manifestations were fever during the acute stage (70.0%), dyspnea during the chronic stage in its cardiac form (53.7%), and constipation during the chronic stage in its digestive form (73.7%). Most patients were diagnosed in the chronic stage (72.0%). Treatment was administered in 56.2% of cases. The mortality rate for the acute stage cases was 24.4%, while for the chronic stage this was 28.4%. Discussion: CD is a parasitic disease endemic to Latin America, with increasing importance due to human and vector migration. In this review, we report reasons for delays in diagnosis and treatment, and trends in medical practices. Community awareness must be increased to improve CD’s diagnoses; health professionals should be appropriately trained to detect and treat infected individuals. Furthermore, public health policies are needed to increase the availability of screening and diagnostic tools, trypanocidal drugs, and, eventually, vaccines.