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CASO CLÍNICO: paciente de 25 días de nacido, que ingresa al servicio de urgencias del Hospital Infantil Napoleón Franco Pareja coneritema umbilical, edema y secreciones purulentas. El examen físico reveló un paciente en aceptables condiciones generales. Sehospitalizó con diagnóstico de onfalitis y se inició tratamiento antibiótico con oxacilina intravenosa. Como consecuencia de lavenopunción el paciente desarrolló un hematoma de aproximadamente 2 cm. de diámetro. El tratamiento antibiótico seadministró durante 9 días continuos, pero sin mejoría del hematoma, motivo por el que se remitió a tercer nivel. El análisis de losresultados de laboratorio en este periodo reveló prolongación en el tiempo parcial de tromboplastina, disminución del Factor VIIIde la coagulación y una anemia de tipo normocítica. Teniendo como base estas pruebas de laboratorio se suspendió laantibióticoterapia y se inició tratamiento con factor VIII recombinante, el paciente presentó una gran mejoría de cuadro clínico, sele dio de alta y se programó seguimiento por el servicio de hemato-oncología-pediátrica.COMENTARIOS: la hemofilia es una enfermedad genética ligada al cromosoma X que se expresa por una disminución del Factor VIII(Hemofilia A) o IX (Hemofilia B) ocasionando alteraciones en la coagulación sanguínea. La prevalencia global de la hemofilia A esaproximadamente de 1 en 5.000 en varones. La hemofilia neonatal exige un abordaje clínico interdisciplinario y el diagnóstico sebasa en los antecedentes familiares positivos y la sospecha clínica ante hemorragias anormales en este grupo de edad. Sediagnostica frecuentemente a partir de los tres años de edad y muy pocas veces se manifiesta en el periodo neonatal. En losprimeros meses de vida la hemofilia puede aparecer como consecuencia de la administración de vitamina K intramuscular o larealización de alguna venopunción; debido a lo anterior aparecen hematomas tal como se presenta en este reporte de caso. Eldiagnóstico rápido y oportuno es importante porque en las hemofilias graves neonatales existe un riesgo elevado de sangradointracraneal que puede comprometer la vida del paciente. La sospecha de hemofilia debe efectuarse en primer lugar por la clínicade hemorragias (hematomas y hemartrosis) en edad temprana. La primera fase de estudio del paciente con hemofilia incluye ladeterminación de pruebas coagulación, en donde la característica principal es la prolongación del TPT con TP normal, pero eldiagnóstico definitivo se hace por la medida de los niveles del factor VIII y factor IX. El tratamiento de elección actualmente es el usode factor VIII recombinante y concentrados de factor IX en neonatos con hemofilia A y B respectivamente. Este tipo de tratamientoevita la transmisión de infecciones que se producen con frecuencia a la hora de realizar transfusiones sanguíneas. La hemofiliadebe considerarse dentro del diagnóstico diferencial en las alteraciones hemorrágicos del recién nacido, incluso sin la existencia deantecedentes familiares. Los pacientes con hemofilia deben ser tratados en centros de hemofilia y/o hospitales de segundo ytercer nivel que cuente con profesionales expertos integrados en un equipo multidisciplinario. El apoyo de las asociacionesnacionales e internacionales de hemofílicos sumados al trabajo conjunto del personal de salud y familiares, son suficientes parasuperar esta enfermedad en etapas tempranas, incluso en el ambiente de desamparo de muchas familias colombianas.

Abstract Background The anti-malarial activity of maslinic acid (MA), a natural triterpene which has been previously shown to exert a parasitostatic action on Plasmodium falciparum cultures, was analysed in vivo by using the Plasmodium yoelii 17XL murine model. Methods ICR mice were infected with P. yoelii and treated with a single dose of MA by a intraperitoneal injection of MA (40 mg kg-1 day-1) followed by identical dose administration for the following three days. Parasitaemia and accumulation of intraerythrocytic stages was monitored microscopically. To assess protective immunity, cured mice were challenged with the same dose of parasites 40 days after recovery from the primary infection and parasitaemia was further monitored for 30 days. Humoral response was tested by ELISA and visualization of specific anti-P. yoelii antibodies was performed by Western-blotting. Results ICR mice treated with MA increased the survival rate from 20% to 80%, showing an arrest of parasite maturation from day 3 to 7 after infection and leading to synchronization of the intraerythrocytic cycle and accumulation of schizonts by day 6, proving that MA also behaves as a parasitostatic agent in vivo. Mice which survived the primary infection displayed lower rates of parasitic growth, showing a decline of parasitaemia after day 15, and complete clearance at day 20. These mice remained immunoprotected, showing not malaria symptoms or detectable parasitaemia after rechallenge with the same lethal strain. The analysis of specific antibodies against P. yoelii, present in mice which survived the infection, showed a significant increase in the number and intensity of immunoreactive proteins, suggesting that the protected mice may trigger a strong humoral response. Conclusion The survival increase observed in MA-treated mice can be explained considering that the parasitostatic effect exerted by this compound during the first days of infection increases the chances to develop effective innate and/or acquired immune responses. MA may represent a new class of anti-malarial compounds which, as a consequence of its parasitostatic action, favours the development of more effective sterilizing immune responses.

Abstract Background Natural products have played an important role as leads for the development of new drugs against malaria. Recent studies have shown that maslinic acid (MA), a natural triterpene obtained from olive pomace, which displays multiple biological and antimicrobial activities, also exerts inhibitory effects on the development of some Apicomplexan, including Eimeria, Toxoplasma and Neospora. To ascertain if MA displays anti-malarial activity, the main objective of this study was to asses the effect of MA on Plasmodium falciparum-infected erythrocytes in vitro. Methods Synchronized P. falciparum-infected erythrocyte cultures were incubated under different conditions with MA, and compared to chloroquine and atovaquone treated cultures. The effects on parasite growth were determined by monitoring the parasitaemia and the accumulation of the different infective stages visualized in thin blood smears. Results MA inhibits the growth of P. falciparum Dd2 and 3D7 strains in infected erythrocytes in, dose-dependent manner, leading to the accumulation of immature forms at IC50 concentrations, while higher doses produced non-viable parasite cells. MA-treated infected-erythrocyte cultures were compared to those treated with chloroquine or atovaquone, showing significant differences in the pattern of accumulation of parasitic stages. Transient MA treatment at different parasite stages showed that the compound targeted intra-erythrocytic processes from early-ring to schizont stage. These results indicate that MA has a parasitostatic effect, which does not inactivate permanently P. falciparum, as the removal of the compound allowed the infection to continue Conclusions MA displays anti-malarial activity at multiple intraerythrocytic stages of the parasite and, depending on the dose and incubation time, behaves as a plasmodial parasitostatic compound. This novel parasitostatic effect appears to be unrelated to previous mechanisms proposed for current anti-malarial drugs, and may be relevant to uncover new prospective plasmodial targets and opens novel possibilities of therapies associated to host immune response.

Abstract Background Improvements on malarial diagnostic methods are currently needed for the correct detection in low-density Plasmodium falciparum infections. Microfluorimetric DNA-based assays have been previously used for evaluation of anti-malarial drug efficacy on Plasmodium infected erythrocytes. Several factors affecting the sensitivity of these methods have been evaluated, and tested for the detection and quantification of the parasite in low parasitaemia conditions. Methods Parasitaemia was assessed by measuring SYBRGreen I® (SGI) and PicoGreen® (PG) fluorescence of P. falciparum Dd2 cultures on human red blood cells. Different modifications of standard methods were tested to improve the detection sensitivity. Calculation of IC50 for chloroquine was used to validate the method. Results Removal of haemoglobin from infected red-blood cells culture (IRBC) increased considerably the fluorescent signal obtained from both SGI and PG. Detergents used for cell lysis also showed to have an effect on the fluorescent signal. Upon depletion of haemoglobin and detergents the fluorescence emission of SGI and PG increased, respectively, 10- and 60-fold, extending notably the dynamic range of the assay. Under these conditions, a 20-fold higher PG vs. SGI fluorescent signal was observed. The estimated limits of detection and quantification for the PG haemoglobin/detergent-depleted method were 0.2% and 0.7% parasitaemia, respectively, which allow the detection of ~10 parasites per microliter. The method was validated on whole blood-infected samples, displaying similar results as those obtained using IRBC. Removal of white-blood cells prior to the assay allowed to increase the accuracy of the measurement, by reducing the relative uncertainty at the limit of detection from 0.5 to 0.1. Conclusion The use of PG microassays on detergent-free, haemoglobin-depleted samples appears as the best choice both for the detection of Plasmodium in low-density infections and anti-malarial drugs tests.

Background: Plants are an important option in the treatment of malaria, especially in endemic regions, and are a less expensive and more accessible alternative with a lower risk of toxicity. Colombia has a great diversity of plants, and evaluation of natural extracts could result in the discovery of new compounds for the development of antimalarial drugs. The purpose of this work was to evaluate the in vitro antiplasmodial activity and the cytotoxicity of plant extracts from the Colombian North Coast against Plasmodium falciparum ., Materials and Methods: The antiplasmodial activity of 12 plant species from the Colombian North Coast that are used in traditional medicine was evaluated through in vitro cultures of P. falciparum , and the cytotoxicity of extracts of these species to human cells was determined. Plant extracts with high antiplasmodial activity were subjected to preliminary phytochemical screening., Results: Extracts from five plants had promising antiplasmodial activity. Specifically, Bursera simaruba (Burseraceae) (bark), Guazuma ulmifolia Lam . (Malvaceae) (whole plant), Murraya exotica L. (Rutaceae) (leaves), Hippomane mancinella L. (Euphorbiaceae) (seeds), and Capparis odoratissima Jacq . (Capparaceae) (leaves). Extracts presented 50% inhibitory concentration values between 1 and 9 μg/ml. Compared to no extract, these active plant extracts did not show cytotoxic effects on mononuclear cells or hemolytic activity in healthy human erythrocytes., Conclusions: The results obtained from this in vitro study of antiplasmodial activity suggest that active plant extracts from the Colombian North Coast are promising for future bioassay-guided fractionation to allow the isolation of active compounds and to elucidate their mechanism of action against Plasmodium spp., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Tropical Parasitology.)

Invasion of Plasmodium into the red blood cell involves the interactions of a substantial number of proteins, with red cell membrane proteins as the most involved throughout the process from entry to exit. The objective of this work was to identify proteins of the human erythrocyte membrane capable of generating an antigenic response to P. falciparum and P. vivax infection, with the goal of searching for new molecular targets of interest with an immunological origin to prevent Plasmodium infection. To identify these proteins, an immunoproteomic technique was carried out in four stages: protein separation (electrophoresis), detection of antigenic proteins (western blotting), identification of proteins of interest (mass spectrometry), and interpretation of the data (bioinformatic analysis). Four proteins were identified from extracts of membrane proteins from erythrocytes infected with P. falciparum: Spectrin, Ankyrin-1, Band 3 and band 4.2, and a single protein was identified from erythrocytes infected with P. vivax: Band 3. These results demonstrate that modifications in the red blood cell membrane during infection with P. falciparum and P. vivax can generate an immune response, altering proteins of great structural and functional importance.

Langerhans cell histiocytosis is a rare pathology with different clinical manifestations in the neonatal period ranging from isolated bone lesions to systemic compromise. We report a case of Langerhans cell histiocytosis including a literature review focused on the clinical manifestations, diagnosis, and treatment. A one-month-old patient was brought to medical consultation with lymphadenopathy and skin lesions, which were initially managed as an infectious pathology. The disease continued its progression without improvement with the treatment until the patient died due to respiratory failure. The lymph node and skin biopsies revealed infiltration of atypical cells with positive immunohistochemistry for S100, CD1, and CD68 confirming Langerhans cell histiocytosis. This disorder represents a great challenge and, therefore, it is important to alert and sensitize medical teams about it for timely diagnosis and management.

Coronavirus disease 2019 (COVID-19) is characterized by respiratory alterations with varied symptoms ranging from mild manifestations to more severe conditions that can cause death. The objective of this narrative review of the literature is to synthesize in a concrete way the information available on potential drugs for the treatment of patients with COVID-19 and to serve as a support guide for health professionals. Taking into account previous experiences for the management of SARS-CoV and MERS-CoV in the past, some of these drugs have been used as a starting point to seek the elimination of SARS-CoV-2. This review presents the current state of research on promising drugs as potential treatments for COVID-19 worldwide and is developed in the text on four types of anti-SARS-Cov-2 agents: regulators of the immune response, intracellular medium modifiers, viral RNA polymerase inhibitors and protease inhibitors. To date all the drugs described in this review need clinical studies to validate their use. However, until the results of these trials are available, the best available evidence should be used for the prevention and treatment of COVID-19.

Introduction: Cleidocraneal dysplasia (CCD) is a rare skeletal autosomal dominant syndrome characterized by dental anomalies and bone abnormalities. These clinical manifestations do not require treatment in most cases. The disease is caused by mutation in the gene RUNX2 (CBAF1), located on the short arm of chromosome 6., Objective: To report a case of CCD and perform a literature review focused on clinical manifestations and diagnosis., Case Report: A 3 year old patient, who was clinically diagnosed with CCD since birth. The patient showed incomplete development of cranial bones, bell-shaped thorax, adequate dentition and presence of clavicles. Molecular analysis reported that the patient is carrying the pathogenic variant c.674G>A in the RUNX2 gene, confirming the diagnosis., Conclusions: The CCD is a rare condition, with special clinical features. It is important to establish early diagnosis in these patients in order to offer a better quality of life, and if necessary, appropriate treatment.

Cytomegalovirus is the most frequent causative agent of perinatal infection and a major cause of acquired viral infections. This case report aims to show the broad clinical spectrum of the presentation of cytomegalovirus infection. The correct classification of congenital or acquired infection and its prompt treatment can prevent complications and sequelae in severe cases. We report the case of an infant with acquired cytomegalovirus infection, which presented an unusual feature of cerebral hemorrhage. The patient was treated with ganciclovir, with a favorable evolution of the clinical symptoms. Cytomegalovirus infection is common in children, both in its congenital and acquired forms. Acquired infection, as portrayed in this case, is mainly characterized by hematological compromise given by the marked thrombocytopenia, which may rarely result in cases of bleeding in the central nervous system. In this patient, no important clinical implications occurred. In addition, most of the acquired infections are self-limited and require no treatment.

We have investigated the mechanism of action of inhibition of the choline kinase of P. falciparum (p.f.-ChoK) by two inhibitors of the human ChoKα, MN58b and RSM-932A, which have previously been shown to be potent antitumoral agents. The efficacy of these inhibitors against p.f.-ChoK is investigated using enzymatic and in vitro assays. While MN58b may enter the choline/phosphocholine binding site, RSM-932A appears to have an altogether novel mechanism of inhibition and is synergistic with respect to both choline and ATP. A model of inhibition for RSM-932A in which this inhibitor traps p.f.-ChoK in a phosphorylated intermediate state blocking phosphate transfer to choline is presented. Importantly, MN58b and RSM-932A have in vitro inhibitory activity in the low nanomolar range and are equally effective against chloroquine-sensitive and chloroquine-resistant strains. RSM-932A and MN58b significantly reduced parasitemia and induced the accumulation of trophozoites and schizonts, blocking intraerythrocytic development and interfering with parasite egress or invasion, suggesting a delay of the parasite maturation stage. The present data provide two new potent structures for the development of antimalarial compounds and validate p.f.-ChoK as an accessible drug target against the parasite.

Introduction: The hemoglobinopathies are a heterogeneous group of congenital anemias from Africa, Asia and the Mediterranean. Due to the migration of this population have spread worldwide, especially in Latin America and the Caribbean region, which Cartagena de Indias is included, with a large proportion of people of African descent. The lack of routine programs that include an appropriate methodology for precise identification of those affected and carriers, impossible to know the real behavior of this disease in our country and an early and appropriate to the patients before the disease manifests itself and produce its serious consequences., Objective: To estimate the incidence and describe the epidemiological profile of hemoglobinopathies in newborns Rafael Calvo Maternity Clinic of Cartagena, in the period from January to June 2010., Methods: Prospective descriptive study of a population of 1,729 newborns. Samples were collected cord blood on filter paper. Isoelectric focusing electrophoresis (IEF )was used to separate the haemoglobins., Results: 94.4% (1,633 samples) were normal (hemoglobin FA), 4.5% (78 samples) were heterozygous for haemoglobin S (HbFAS), 1% (17samples) were heterozygous for haemoglobin C (hemoglobin FAC) and 0.1% (1 sample) was double heterozygous SC (hemoglobin FSC)., Conclusion: Due to the high incidence of hemoglobinopathies found in this pilot study highlights the importance and necessity of establishing an obligatory neonatal screening in the city of Cartagena, in order to make a timely diagnosis and monitoring of affected and carrier.

Most drugs against malaria that are available or under development target a single process of the parasite infective cycle, favouring the appearance of resistant mutants which are easily spread in areas under chemotherapeutic treatments. Maslinic acid (MA) is a low toxic natural pentacyclic triterpene for which a wide variety of biological and therapeutic activities have been reported. Previous work revealed that Plasmodium falciparum erythrocytic cultures were inhibited by MA, which was able to hinder the maturation from ring to schizont stage and, as a consequence, prevent the release of merozoites and the subsequent invasion. We show here that MA effectively inhibits the proteolytic processing of the merozoite surface protein complex, probably by inhibition of PfSUB1. In addition, MA was also found to inhibit metalloproteases of the M16 family by a non-chelating mechanism, suggesting the possible hindrance of plasmodial metalloproteases belonging to that family, such as falcilysin and apicoplast peptide-processing proteases. Finally, in silico target screening was used to search for other potential binding targets that may have remained undetected. Among the targets identified, the method recovered two for which experimental activity could be confirmed, and suggested several putative new targets to which MA could have affinity. One of these unreported targets, phospholipase A2, was shown to be partially inhibited by MA. These results suggest that MA may behave as a multi-targeted drug against the intra-erythrocytic cycle of Plasmodium, providing a new tool to investigate the synergistic effect of inhibiting several unrelated processes with a single compound, a new concept in antimalarial research., (© 2011 The Authors Journal compilation © 2011 FEBS.)

Background: The anti-malarial activity of maslinic acid (MA), a natural triterpene which has been previously shown to exert a parasitostatic action on Plasmodium falciparum cultures, was analysed in vivo by using the Plasmodium yoelii 17XL murine model., Methods: ICR mice were infected with P. yoelii and treated with a single dose of MA by a intraperitoneal injection of MA (40 mg kg(-1) day(-1)) followed by identical dose administration for the following three days. Parasitaemia and accumulation of intraerythrocytic stages was monitored microscopically. To assess protective immunity, cured mice were challenged with the same dose of parasites 40 days after recovery from the primary infection and parasitaemia was further monitored for 30 days. Humoral response was tested by ELISA and visualization of specific anti-P. yoelii antibodies was performed by Western-blotting., Results: ICR mice treated with MA increased the survival rate from 20% to 80%, showing an arrest of parasite maturation from day 3 to 7 after infection and leading to synchronization of the intraerythrocytic cycle and accumulation of schizonts by day 6, proving that MA also behaves as a parasitostatic agent in vivo. Mice which survived the primary infection displayed lower rates of parasitic growth, showing a decline of parasitaemia after day 15, and complete clearance at day 20. These mice remained immunoprotected, showing not malaria symptoms or detectable parasitaemia after rechallenge with the same lethal strain. The analysis of specific antibodies against P. yoelii, present in mice which survived the infection, showed a significant increase in the number and intensity of immunoreactive proteins, suggesting that the protected mice may trigger a strong humoral response., Conclusion: The survival increase observed in MA-treated mice can be explained considering that the parasitostatic effect exerted by this compound during the first days of infection increases the chances to develop effective innate and/or acquired immune responses. MA may represent a new class of anti-malarial compounds which, as a consequence of its parasitostatic action, favours the development of more effective sterilizing immune responses.

Background: Natural products have played an important role as leads for the development of new drugs against malaria. Recent studies have shown that maslinic acid (MA), a natural triterpene obtained from olive pomace, which displays multiple biological and antimicrobial activities, also exerts inhibitory effects on the development of some Apicomplexan, including Eimeria, Toxoplasma and Neospora. To ascertain if MA displays anti-malarial activity, the main objective of this study was to asses the effect of MA on Plasmodium falciparum-infected erythrocytes in vitro., Methods: Synchronized P. falciparum-infected erythrocyte cultures were incubated under different conditions with MA, and compared to chloroquine and atovaquone treated cultures. The effects on parasite growth were determined by monitoring the parasitaemia and the accumulation of the different infective stages visualized in thin blood smears., Results: MA inhibits the growth of P. falciparum Dd2 and 3D7 strains in infected erythrocytes in, dose-dependent manner, leading to the accumulation of immature forms at IC50 concentrations, while higher doses produced non-viable parasite cells. MA-treated infected-erythrocyte cultures were compared to those treated with chloroquine or atovaquone, showing significant differences in the pattern of accumulation of parasitic stages. Transient MA treatment at different parasite stages showed that the compound targeted intra-erythrocytic processes from early-ring to schizont stage. These results indicate that MA has a parasitostatic effect, which does not inactivate permanently P. falciparum, as the removal of the compound allowed the infection to continue, Conclusions: MA displays anti-malarial activity at multiple intraerythrocytic stages of the parasite and, depending on the dose and incubation time, behaves as a plasmodial parasitostatic compound. This novel parasitostatic effect appears to be unrelated to previous mechanisms proposed for current anti-malarial drugs, and may be relevant to uncover new prospective plasmodial targets and opens novel possibilities of therapies associated to host immune response.

Background: Improvements on malarial diagnostic methods are currently needed for the correct detection in low-density Plasmodium falciparum infections. Microfluorimetric DNA-based assays have been previously used for evaluation of anti-malarial drug efficacy on Plasmodium infected erythrocytes. Several factors affecting the sensitivity of these methods have been evaluated, and tested for the detection and quantification of the parasite in low parasitaemia conditions., Methods: Parasitaemia was assessed by measuring SYBRGreen I (SGI) and PicoGreen (PG) fluorescence of P. falciparum Dd2 cultures on human red blood cells. Different modifications of standard methods were tested to improve the detection sensitivity. Calculation of IC50 for chloroquine was used to validate the method., Results: Removal of haemoglobin from infected red-blood cells culture (IRBC) increased considerably the fluorescent signal obtained from both SGI and PG. Detergents used for cell lysis also showed to have an effect on the fluorescent signal. Upon depletion of haemoglobin and detergents the fluorescence emission of SGI and PG increased, respectively, 10- and 60-fold, extending notably the dynamic range of the assay. Under these conditions, a 20-fold higher PG vs. SGI fluorescent signal was observed. The estimated limits of detection and quantification for the PG haemoglobin/detergent-depleted method were 0.2% and 0.7% parasitaemia, respectively, which allow the detection of ~10 parasites per microliter. The method was validated on whole blood-infected samples, displaying similar results as those obtained using IRBC. Removal of white-blood cells prior to the assay allowed to increase the accuracy of the measurement, by reducing the relative uncertainty at the limit of detection from 0.5 to 0.1., Conclusion: The use of PG microassays on detergent-free, haemoglobin-depleted samples appears as the best choice both for the detection of Plasmodium in low-density infections and anti-malarial drugs tests.

This protocol describes a method for preparing cultures of Plasmodium falciparum synchronized at any intraerythrocytic stage. Using this method, around 60% parasitized cells may be obtained. On the basis of Trager and Jensen's original continuous culture method, our approach relies on the use of fresh human blood not older than 2 weeks, a low hematocrit between 0.8 and 1.5%, a starting frozen inoculum of 10% ring-stage parasitemia, human serum replaced with AlbuMAX I and alternating sorbitol and Percoll synchronization methods to shorten the cycle window to 4-6 h and reduce sorbitol toxicity. From our synchronized high parasite density cultures, 3-5 ml of infected red blood cells can be obtained in 1 week, corresponding to 1.2 mg of total parasite protein per ml of harvested culture. On the basis of the variables parasitemia and packed cell volume, we provide an equation to accurately calculate the amount of complete medium required every 24 h corrected for the cycle stage and capacity of the culture flask. Ten days suffice to complete the protocol from a frozen stock of parasites.