Current drug strategies for the treatment and control of schistosomiasis.

INTRODUCTION: Schistosomiasis, one of the current Neglected Tropical Diseases (NTDs) affects over 230 million people globally, with nearly 700 million at risk in more than 74 countries. Praziquantel (PZQ) has served as the primary treatment for the past four decades; however, its effectiveness is limited as it solely eliminates adult worms. In regions where infections are frequent, PZQ exhibits only temporary efficacy and has restricted potential to disrupt the prolonged transmission of the disease. AREAS COVERED: A comprehensive exploration using the PubMed database was conducted to review current pharmacotherapy approaches for schistosomiasis. This review also encompasses recent research findings related to potential novel therapeutics and the repurposing of existing drugs. EXPERT OPINION: Current schistosoma treatment strategies, primarily relying on PZQ, face challenges like temporary effectiveness and limited impact on disease transmission. Drug repurposing, due to economic constraints, is decisive for NTDs. Despite PZQ's efficacy, its failure to prevent reinfection highlights the need for complementary strategies, especially in regions with persistent environmental foci. Integrating therapies against diverse schistosome stages boosts efficacy and impedes resistance. Uncovering novel agents is essential to address resistance concerns in tackling this neglected tropical disease. Integrated strategies present a comprehensive approach to navigate the complex challenges.

Identification of Genomic Regions Implicated in Susceptibility to Schistosoma mansoni Infection in a Murine Backcross Genetic Model.

Only a small number of infected people are highly susceptible to schistosomiasis, showing high levels of infection or severe liver fibrosis. The susceptibility to schistosome infection is influenced by genetic background. To assess the genetic basis of susceptibility and identify the chromosomal regions involved, a backcross strategy was employed to generate high variation in schistosomiasis susceptibility. This strategy involved crossing the resistant C57BL/6J mouse strain with the susceptible CBA/2J strain. The resulting F1 females (C57BL/6J × CBA/2J) were then backcrossed with CBA/2J males to generate the backcross (BX) cohort. The BX mice exhibited a range of phenotypes, with disease severity varying from mild to severe disease, lacking a fully resistant group. We observed four levels of infection intensity using cluster and principal component analyses and K-means based on parasitological, pathological, and immunological trait measurements. The mice were genotyped with 961 informative SNPs, leading to the identification of 19 new quantitative trait loci (QTL) associated with parasite burden, liver lesions, white blood cell populations, and antibody responses. Two QTLs located on chromosomes 15 and 18 were linked to the number of granulomas, liver lesions, and IgM levels. The corresponding syntenic human regions are located in chromosomes 8 and 18. None of the significant QTLs had been reported previously.

Evaluation of the Immunomodulatory Effect of the Recombinant 14-3-3 and Major Antigen Proteins of Strongyloides stercoralis against an Infection by S. venezuelensis.

Strongyloidiasis, caused by Strongyloides stercoralis, is a neglected parasitic disease that represents a serious public health problem. In immunocompromised patients, this parasitosis can result in hyperinfection or disseminated disease with high levels of mortality. In previous studies, the mRNAs encoding for the 14-3-3 and major antigen proteins were found to be expressed at high levels in S. stercoralis L3 larvae, suggesting potential key roles in parasite-host interactions. We have produced them as recombinant proteins (rSs14-3-3 and rSsMA) in a bacterial protein expression system. The serum levels of anti-rSs14-3-3 and anti-rSsMA IgGs are increased upon infection with S. venezuelensis, validating the use of the mouse model since the native 14-3-3 and MA proteins induce an immune response. Each recombinant protein was formulated in the adjuvant adaptation (ADAD) vaccination system and injected twice, subcutaneously, in CD1 mice that were experimentally infected with 3000 S. venezuelensis L3 to evaluate their protective and immunomodulatory activity. Our results, including the number of parthenogenetic females, number of eggs in stool samples and the analysis of the splenic and intestinal indexes, show that the vaccines did not protect against infection. The immunization with rSs14-3-3 induced changes in the cytokine profile in mice, producing higher expression of IL-10, TGF-ß, IL-13 and TNF-α in the spleen, suggesting a Th2/Treg-type response with an increase in TNF-α levels, confirming its role as an immunomodulator.

Seroprevalence of SARS-CoV-2 Antibodies and Factors Associated with Seropositivity at the University of Salamanca: The DIANCUSAL Study.

BACKGROUND: Systematic screening for antibodies against SARS-CoV-2 is a crucial tool for surveillance of the COVID-19 pandemic. The University of Salamanca (USAL) in Spain designed a project called "DIANCUSAL" (Diagnosis of New Coronavirus, COVID-19, in University of Salamanca) to measure antibodies against SARS-CoV-2 among its ~34,000 students and academic staff, as the influence of the university community in the spread of the SARS-CoV-2 pandemic in the city of Salamanca and neighboring towns hosting USAL campuses could be substantial. OBJECTIVE: The aim of this study was to estimate the prevalence of SARS-CoV-2 antibodies among USAL students, professors and staff and to evaluate the demographic, academic, clinical and lifestyle and behavioral factors related to seropositivity. METHODOLOGY: The DIANCUSAL study is an ongoing university population-based cross-sectional study, with the work described herein conducted from July-October 2020. All USAL students, professors and staff were invited to complete an anonymized questionnaire. Seroprevalence of anti-SARS-CoV-2 antibodies was detected and quantified by using chemiluminescent assays for IgG and IgM. PRINCIPAL FINDINGS: A total of 8197 (24.71%) participants were included. The mean age was 31.4 (14.5 SD) years, and 66.0% of the participants were female. The seroprevalence was 8.25% overall and was highest for students from the education campus (12.5%) and professors from the biomedical campus (12.6%), with significant differences among faculties (p = 0.006). Based on the questionnaire, loss of smell and fever were the symptoms most strongly associated with seropositivity, and 22.6% of seropositive participants were asymptomatic. Social distancing was the most effective hygiene measure (p = 0.0007). There were significant differences in seroprevalence between participants with and without household exposure to SARS-CoV-2 (p = 0.0000), but not between students who lived in private homes and those who lived in dormitories. IgG antibodies decreased over time in the participants with confirmed self-reported COVID-19 diagnoses. CONCLUSIONS: The analysis revealed an overall 8.25% seroprevalence at the end of October 2020, with a higher seroprevalence in students than in staff. Thus, there is no need for tailored measures for the USAL community as the official average seroprevalence in the area was similar (7.8% at 22 June and 12.4 at 15 November of 2020). Instead, USAL members should comply with public health measures.

In Vitro Antischistosomal Activity of the Argemone mexicana Methanolic Extract and Its Main Component Berberine.

BACKGROUND: Schistosomiasis has been identified as a major public health problem in tropical countries. The present study aimed to investigate the schistosomicidal effects of the methanolic extract of Argemone mexicana L. and its active component, berberine against Schistosoma mansoni on in-vitro experiments. METHODS: S. mansoni adults were used. Various concentrations of the methanolic extract (10 - 200 µg/ml) and berberine (2.5 - 50 µM) were tested from 24 to 72 h. The viability of S. mansoni was confirmed with an invertoscope-microscope. Furthermore, cytotoxic (Hemolysis test), and antioxidant (DPPH radical scavenging assay) capacities were determined. RESULTS: The viability tests on S. mansoni showed that A. mexicana at 50 µg/mL is lethal at 48 h and berberine at 10 µM is lethal at 24 h. The hemolytic activity at 1,000 µg/mL was 2.9% for A. mexicana and 90.2% for berberine. The antioxidant capacities shown by A. mexicana and berberine, were EC50 156.3 and 84.1 µg/mL, respectively. CONCLUSION: The extract of A. mexicana and berberine demonstrated high antischistosomal activities in low concentration and short exposure time on the in-vitro model.

The effect of ivermectin alone and in combination with cobicistat or elacridar in experimental Schistosoma mansoni infection in mice.

Schistosoma mansoni is less susceptible to the antiparasitic drug ivermectin than other helminths. By inhibiting the P-glycoprotein or cytochrome P450 3A in mice host or parasites in a murine model, we aimed at increasing the sensitivity of S. mansoni to the drug and thus preventing infection. We assigned 124 BALB/c mice to no treatment, treatment with ivermectin only or a combination of ivermectin with either cobicistat or elacridar once daily for three days before infecting them with 150 S. mansoni cercariae each. The assignment was done by batches without an explicit randomization code. Toxicity was monitored. At eight weeks post-infection, mice were euthanized. We determined number of eggs in intestine and liver, adult worms in portal and mesenteric veins. Disease was assessed by counting granulomas/cm2 of liver and studying organ weight indices and total weight. IgG levels in serum were also considered. No difference between groups treated with ivermectin only or in combination with cobicistat or elacridar compared with untreated, infected controls. Most mice treated with ivermectin and elacridar suffered severe neurological toxicity. In conclusion, systemic treatment with ivermectin, even in the presence of pharmacological inhibition of P-glycoprotein or cytochrome P450 3A, did not result in effective prophylaxis for S. mansoni infection in an experimental murine model.

T Cell Peptides Derived from Invasive Stages of Schistosoma mansoni as Potential Schistosomiasis Vaccine.

Schistosomiasis is a parasitic disease that affects 143 million people in endemic countries. This work analyzed overexpressed sequences from the cercaria phase to the early schistosomulum phase using bioinformatics tools to predict host interaction and selected proteins for predicting T cell epitopes. The final peptides were chemically synthesized, and their toxicity was evaluated in vitro. Peptides were formulated in the Adjuvant Adaptation (ADAD) vaccination system and injected into BALB/c mice that were challenged with S. mansoni cercariae to assess protection and immunogenicity. A total of 39 highly expressed S.mansoni proteins were identified as being of potential interest. Three T cell peptides predicted to bind MHC mouse and human class II were synthesized and formulated for vaccination. SmGSP and SmIKE reduced the number of eggs trapped in the liver by more than 50% in challenged BALB/c mice. The liver of mice vaccinated with either SmGSP or SmTNP had a significantly reduced affected liver surface. Transcriptome-based T cell peptides elicit partial protection and could be candidates for a multiantigen vaccine.

Berberine: A nematocidal alkaloid from Argemone mexicana against Strongyloides venezuelensis.

Strongyloidiasis is a parasitosis that represents a public health problem, in tropical regions. The present study aimed to investigate the anthelmintic effects of several extracts of Argemone mexicana, as well as its main component berberine (Ber) against the third-stage larvae (L3) of Strongyloides venezuelensis in-vitro experiments. Also, the anti-hemolytic activity of the extract, fractions, and Ber were tested in human erythrocytes. A dose-response anthelminthic bioassay demonstrated Ber as the most effective component, followed by methanolic subfraction (Fr3) and finally the crude extract of A. mexicana (Am) showing LC50 response values of 1.6, 19.5, and 92.1 µg/mL, at 96 h respectively. Also, Am, Fr3, and Ber did not produce significant hemolysis against human erythrocytes (p ≤ 0.05). Am and Fr3 showed erythrocyte protection effect capacity at the membrane level (p ≤ 0.05). Furthermore, Ber was found to have an antioxidant activity of 168.18 µg/mL. According to the results, the Fr3 of A. mexicana, and particularly Ber, exhibited potent in-vitro effects against L3 of S. venezuelensis, without hemolytic activity against human erythrocytes and presented good antioxidant capacity. In conclusion, the extracts of A. mexicana and the main component have activity against S. venezuelensis, nevertheless, further studies are required to elucidate the mechanism of action.

Toker cell hyperplasia in Zuska disease: A tricky association.

Toker cells (TCs) are sometimes present in the nipple epidermis as oval cells with pale cytoplasm and roundish nuclei. In most cases, TCs may be easily distinguished from cancerous cells of Paget disease of the nipple (PCs). Especially in TC hyperplasia, in which mild-to-moderate atypia may be present, it may be challenging to distinguish between TCs and PCs. The combination of chronic inflammatory changes in the nipple, in the context of Zuska disease, and TC hyperplasia, may easily lead to an erroneous diagnosis of mammary Paget disease.

Molecular Markers for Detecting Schistosoma Species by Loop-Mediated Isothermal Amplification.

Schistosomiasis is considered a neglected parasitic disease. Around 280,000 people die from it annually, and more than 779 million people are at risk of getting infected. The schistosome species which infect human beings are Schistosoma mansoni, Schistosoma haematobium, Schistosoma intercalatum, Schistosoma japonicum, Schistosoma guineensis, and Schistosoma mekongi. This disease is also of veterinary significance; the most important species being Schistosoma bovis since it causes the disease in around 160 million livestock in Africa and Asia. This work was aimed at designing and developing a genus-specific loop-mediated isothermal amplification (LAMP) method for detecting the most important schistosome species affecting humans and for the species-specific detection of S. bovis. Bioinformatics tools were used for primer design, and the LAMP method was standardised for detecting the ITS-1 region from S. intercalatum, S. haematobium, S. mansoni, S. japonicum, and S. bovis DNA (generic test) and the NADH 1 gene for specifically detecting S. bovis (at different DNA concentrations). Detection limits achieved were 1 pg DNA for S. mansoni, 0.1 pg for S. haematobium, 1 pg for S. intercalatum, and 10 pg for S. bovis. No amplification for S. japonicum DNA was obtained. The LAMP designed for the amplification of S. bovis NADH-1 worked specifically for this species, and no other DNA from other schistosome species included in the study was amplified. Two highly sensitive LAMP methods for detecting different Schistosoma species important for human and veterinary health were standardised. These methods could be very useful for the diagnosis and surveillance of schistosome infections.

Imported Mansonella perstans infection in Spain.

BACKGROUND: Mansonella perstans infection can be considered one of the most neglected tropical infectious diseases. Very few studies have reported on the clinical picture caused by infection with this nematode. Therefore, our study was aimed to describe the clinical patterns and treatment of imported M. perstans infection by migrants from Africa. METHODS: The present study evaluated a large cohort of migrants who have been diagnosed, examined and treated for imported M. perstans infection at a Spanish reference center (Hospital Carlos III Tropical Medicine Unit, Madrid, Spain) over a 19-year period. Most patients voluntarily attend the emergency unit or are referred from primary care or general hospitals in Madrid. Chi-square test was used to compare the association between categorical variables. The continuous variables were compared by Student's t-test or the Mann-Whitney test. The corresponding regression models were used for multivariate analysis. RESULTS: Five hundred three cases of migrants from tropical and subtropical areas with M. perstans infection were identified. Two hundred sixty-four patients were female (52.5%). The mean age (± SD) was 44.6 ± 18.2 years (range: 16-93 years). The mean time (± SD) between the arrival in Spain and the first consultation was 8.6 ± 18.0 months. The major origin of the patients was Equatorial Guinea (97.6%). Regarding the clinical picture, 257 patients were asymptomatic (54.7%) and 228 were symptomatic (45.3%); 190 patients had pruritus (37.8%), 50 (9.9%) had arthralgia, 18 patients had Calabar-like swelling (3.6%), and 15 (3%) had abdominal pain. Four hundred forty-two (87.9%) migrants had hyper-IgE, and 340 (67.6%) had eosinophilia. One hundred ninety-five patients had coinfections with other filarial nematodes (38.8%), and 308 migrants had only M. perstans infection (61.2%). Four hundred thirty-seven cases (86.9%) had been treated with anti-filarial drugs; 292 cases were treated with one anti-filarial drug, and 145 cases were treated with combined anti-filarial therapy. Additionally, 20 (4%) cases received steroids and 38 (7.6%) cases received antihistamines. CONCLUSIONS: A long series of M. perstans infections is presented in sub-Saharan immigrants whose data indicate that it should be included in the differential diagnosis in patients with pruritus or analytical alterations such as eosinophilia or hyper-IgE presentation, and they also have a high number of coinfections with other microorganisms whose treatment needs to be protocolized.

Performance of prognostic scoring systems in elderly patients with acute myeloid leukaemia on intensive chemotherapy: A PETHEMA registry study.

Selection of elderly patients (aged ≥60 years) for intensive chemotherapy treatment of acute myeloblastic leukaemia (AML) remains challenging. Several cooperative groups such as Acute Leukaemia French Association (ALFA), Haematological Oncology Clinical Studies Group (HOCSG) and MD Anderson Cancer Center (MDACC) have developed predictive models to select those patients who can benefit from intensive chemotherapy. Our purpose is to validate and compare these three models in a cohort of patients treated in real-life setting. For this, a total of 1724 elderly AML patients and treated with intensive chemotherapy regimens were identified in the PETHEMA registry. Median age was 67.2 years (range, 60-84,9) and median overall survival [OS] 9 months (95 % confidence interval [CI], 8.2-9.7). Taking into account the ALFA group's model, patients likely to benefit from intensive chemotherapy had longer OS (14 months, 95 % CI 12.3-15.7) than those unlikely to benefit (5 months, 95 % CI 4.1-5.9; p < 0.001). Significant differences in OS were observed between patients with favourable risk (17 months, 95 % CI 13.2-20.7), intermediate risk (11 months, 95 % CI 9.3-12.6) and adverse risk (6 months, 95 % CI 5.1-6.4; p < 0.001) according to the HOCSG model. No significant differences in OS were observed between patients with 0, 1, 2 or ≥3 points according to the MDACC model. However, when patients with ≥1 point were compared with those with 0 points, median OS was significantly longer in the latter [15 months (95 % CI 12.1-17.8) vs 7 (95 % CI 5.7-8.5)]. This retrospective study validates predictive models proposed by the ALFA, HOCSG and MDACC groups in this real-life cohort.

A Trypanosoma cruzi Genome Tandem Repetitive Satellite DNA Sequence as a Molecular Marker for a LAMP Assay for Diagnosing Chagas' Disease.

Chagas' disease is a neglected tropical disease caused by Trypanosoma cruzi which is endemic throughout Latin America and is spread by worldwide migration. Diagnosis is currently limited to serological and molecular techniques having variations regarding their sensitivity and specificity. This work was aimed at developing a new sensitive, applicable, and cost-effective molecular diagnosis technique for loop-mediated isothermal amplification-based detection of T. cruzi (Tc-LAMP). The results led to determining a highly homologous satellite repeat region (231 bp) among parasite strains as a molecular marker for diagnosing the disease. Tc-LAMP was performed correctly for detecting parasite DNA (5 fg for the CL Brener strain and 50 fg for the DM28, TcVI, and TcI strains). Assay results proved negative for DNA from 16 helminth species and 7 protozoa, including Leishmania spp. Tc-LAMP based on the highly repeated T. cruzi satellite region is thus proposed as an important alternative for diagnosing T. cruzi infection, overcoming other methods' limitations such as their analytic capability, speed, and requiring specialized equipment or highly trained personnel. Tc-LAMP could be easily adapted for point-of-care testing in areas having limited resources.

Loiasis in sub-Saharan migrants living in Spain with emphasis of cases from Equatorial Guinea.

BACKGROUND: Loiasis is an uncommon and poorly understood parasitic disease outside endemic areas of Africa. The aim of this study was to describe the clinical and biological patterns and treatment of imported loiasis by sub-Saharan migrants diagnosed in Madrid, Spain. METHODS: A retrospective study was conducted with sub-Saharan immigrants seen at the Tropical Medicine Unit of the Carlos III Hospital in Madrid, Spain, a reference center, over 19 years. Categorical variables were expressed as frequency counts and percentages. Continuous variables were expressed as the mean and standard deviation (SD) or median and interquartile range (IQR: Q3-Q1). Chi-square tests were used to assess the association between categorical variables. The measured outcomes were expressed as the odds ratio (OR) with a 95% confidential interval. Continuous variables were compared by Student's t-tests or Mann-Whitney U tests. Binary logistic regression models were used. P <  0.05 was considered a statistically significant difference. RESULTS: One hundred thirty-one migrants from tropical and subtropical areas with loiasis were identified. Forty-nine patients were male (37.4%). The migrants' mean age (±SD) was 42.3 ± 17.3 years, and 124 (94.7%) were from Equatorial Guinea. The median time (IQR) between arrival in Spain and the first consultation was 2 (1-7) months. One hundred fifteen migrants had eosinophilia, and one hundred thirteen had hyper-IgE syndrome. Fifty-seven patients had pruritus (43.5%), and thirty patients had Calabar swelling (22.9%). Seventy-three patients had coinfections with other filarial nematodes (54.2%), and 58 migrants had only Loa loa infections (45.8%). One hundred two patients (77.9%) were treated; 45.1% (46/102) patients were treated with one drug, and 54.9% (56/102) patients were treated with combined therapy. Adverse reactions were described in 14 (10.7%) migrants. CONCLUSIONS: Our patients presented early clinical manifestations and few atypical features. Thus, physicians should systematically consider loiasis in migrants with a typical presentation. However, considering that 72.5% of the patients had only positive microfilaremia without any symptoms, we suggest searching for microfilaremia in every migrant from endemic countries for loiasis presenting with eosinophilia.

Leishmania heme uptake involves LmFLVCRb, a novel porphyrin transporter essential for the parasite.

Leishmaniasis comprises a group of neglected diseases caused by the protozoan parasite Leishmania spp. As is the case for other trypanosomatid parasites, Leishmania is auxotrophic for heme and must scavenge this essential compound from its human host. In mammals, the SLC transporter FLVCR2 mediates heme import across the plasma membrane. Herein we identify and characterize Leishmania major FLVCRb (LmFLVCRb), the first member of the FLVCR family studied in a non-metazoan organism. This protein localizes to the plasma membrane of the parasite and is able to bind heme. LmFLVCRb levels in Leishmania, which are modulated by overexpression thereof or the abrogation of an LmFLVCRb allele, correlate with the ability of the parasite to take up porphyrins. Moreover, injection of LmFLVCRb cRNA to Xenopus laevis oocytes provides these cells with the ability to take up heme. This process is temperature dependent, requires monovalent ions and is inhibited at basic pH, characteristics shared by the uptake of heme by Leishmania parasites. Interestingly, LmFLVCRb is essential as CRISPR/Cas9-mediated knockout parasites were only obtained in the presence of an episomal copy of the gene. In addition, deletion of just one of the alleles of the LmFLVCRb gene markedly impairs parasite replication as intracellular amastigotes as well as its virulence in an in vivo model of cutaneous leishmaniasis. Collectively, these results show that Leishmania parasites can rescue heme through plasma membrane transporter LFLVCRb, which could constitute a novel target for therapeutic intervention against Leishmania and probably other trypanosomatid parasites in which FLVCR genes are also present.

Detection of Schistosoma mansoni-derived DNA in human urine samples by loop-mediated isothermal amplification (LAMP).

BACKGROUND: Schistosoma mansoni is the main species causing hepatic and intestinal schistosomiasis in Sub-Saharan Africa, and it is the only species in South America. Adult stages of the parasite reside in the mesenteric venous plexus of infected hosts, and eggs are shed in feces. Collecting patient stool samples for S. mansoni diagnostic purposes is difficult in large-scale field trials. Urine samples would be an alternative approach for molecular S. mansoni detection since they have several advantages over stool samples, including better handling, management and storage. Additionally, loop-mediated isothermal amplification (LAMP) technology is a powerful molecular diagnostic tool for infectious diseases, particularly under field conditions in developing countries. The present study aimed to assess the effectiveness of our previously developed LAMP assay (SmMIT-LAMP) for S. mansoni-specific detection in clinical urine samples. METHODOLOGY/PRINCIPAL FINDINGS: The sensitivity of SmMIT-LAMP in urine was established in simulated fresh human urine samples artificially spiked with genomic DNA from S. mansoni. LAMP for 120 min instead of 60 min improved the sensitivity, reaching values of 0.01 fg/µL. A set of well-defined frozen stored human urine samples collected from Sub-Saharan immigrant patients was selected from a biobank to evaluate the diagnostic validity of SmMIT-LAMP. The set included urine samples from patients with microscopy-confirmed infections with S. mansoni, S. haematobium and other nonschistosome parasites, as well as urine samples from patients with microscopy-negative eosinophilia without a confirmed diagnosis. The SmMIT-LAMP was incubated for 60 and 120 min. A longer incubation time was shown to increase the LAMP-positive results in patient urine samples. We also tested urine samples from mice experimentally infected with S. mansoni, and LAMP-positive results were obtained from the third week after infection. A real-time LAMP assay was also performed with three individual urine samples. CONCLUSIONS/SIGNIFICANCE: The SmMIT-LAMP could effectively detect S. mansoni DNA in mouse urine samples and produced promising results for human clinical samples. The detection of S. mansoni DNA in mouse urine samples from the third week after infection indicates that early diagnosis of active S. mansoni infection is possible using urine as a source of DNA. Further studies are still needed, but our method could be used as a promising molecular tool applicable to urine samples to diagnose human intestinal schistosomiasis caused by S. mansoni.

Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations.

Bovine leukocyte antigens (BoLA) have been used as disease markers and immunological traits in cattle due to their primary role in pathogen recognition by the immune system. A higher MHC allele diversity in a population will allow presenting a broader peptide repertoire. However, loss of overall diversity due to domestication process can decrease a population's peptide repertoire. Within the context of zebu and taurine cattle populations, BoLA-DRB3 genetic diversity in Spanish Morucha and Colombian Normande cattle was analyzed and an approach to estimate functional diversity was performed. Sequence-based typing was used for identifying 29, 23, 27, and 28 alleles in Spanish Morucha, Nariño-, Boyacá-, and Cundinamarca-Normande cattle, respectively. These breeds had remarkably low heterozygosity levels and the Hardy-Weinberg principle revealed significant heterozygote deficiency. FST and DA genetic distance showed that Colombian Normande populations had greater variability than other phenotypically homogeneous breeds, such as Holstein. It was also found that Spanish Morucha cattle were strongly differentiated from other cattle breeds. Spanish Morucha had greater divergence in the peptide-binding region regarding other cattle breeds. However, peptide-binding region covariation indicated that the potential peptide repertoire seemed equivalent among cattle breeds. Despite the genetic divergence observed, the extent of the potential peptide repertoire in the cattle populations studied appears to be similar and thus their pathogen recognition potential should be equivalent, suggesting that functional diversity might persist in the face of bottlenecks imposed by domestication and breeding.

Dermatological manifestations in onchocerciasis: A retrospective study of 400 imported cases / Manifestaciones dermatológicas en oncocercosis: estudio retrospectivo de 400 casos importados

INTRODUCTION: Onchocerciasis is caused by Onchocerca volvulus and mainly leads to pruritus and skin and visual disorders, including blindness. Seventeen million people are infected in 38 countries; 31 of these are in sub-Saharan Africa, six in Latin America and one on the Arabian Peninsula. More than 99% of cases occur in sub-Saharan Africa where 120 million people are at risk of infection. Eye disorders have been well-documented; however, skin disorders have not been described accurately. The objective of our study was to describe the epidemiology, main skin manifestations and treatment of imported onchocerciasis. MATERIAL AND METHODS: A retrospective study was thus conducted by analysing the main demographic, clinical and treatment data regarding a cohort of 400 patients attending a reference clinical unit over a 17-year period. RESULTS: Most patients were female (55%) with mean age 37.5 ± 16.7 years. All the migrants came from sub-Saharan countries. The most frequently occurring dermatological symptom was pruritus. Ivermectin had been used as first-line therapy and adverse reactions had been described in 11 patients (3.2%). CONCLUSIONS: The results indicate the fact that there should be a clinical suspicion of onchocerciasis regarding immigrants from endemic areas having skin lesions compatible with the disease's profile or asymptomatic patients having eosinophilia or unexplained high IgE. Moreover, skin snips from the buttocks region were very fruitful and treatment with ivermectin was seen to be safe. This is the largest case series regarding imported onchocerciasis described up to the present time

INTRODUCCIÓN: La oncocercosis está causada por Onchocerca volvulus que produce fundamentalmente trastornos cutáneos, prurito y alteraciones visuales. Diecisiete millones de personas están infectadas en 38 países; 31 de ellos en África subsahariana, 6 en América Latina y uno en la península arábiga. Más del 99% de los casos se producen en el África subsahariana, donde 120 millones de personas están en riesgo de infección. Mientras los trastornos oculares han sido bien documentados, los trastornos cutáneos no se han descrito con precisión. El objetivo de nuestro estudio es describir la epidemiología, las principales manifestaciones cutáneas y el tratamiento de la oncocercosis importada. MATERIAL Y MÉTODOS: Estudio retrospectivo de una cohorte de 400 pacientes atendidos en una unidad de referencia a lo largo de un período de 17 años con los principales datos demográficos, clínicos y de tratamiento. RESULTADOS: La mayoría de pacientes eran mujeres (55%) con una edad media de 37,5 ± 16,7 años. Todos los migrantes procedían de países subsaharianos. El síntoma dermatológico más frecuente fue el prurito. La ivermectina fue el fármaco de elección, describiéndose reacciones adversas en 11 pacientes (3,2%). CONCLUSIONES: Los resultados señalan de que se debe mantener una sospecha clínica de oncocercosis en inmigrantes procedentes de áreas endémicas y lesiones cutáneas sugerentes o en pacientes asintomáticos con eosinofilia o IgE inexplicada. Además, los pellizcos cutáneos de glúteos fueron altamente rentables. El tratamiento con ivermectina es seguro. Esta es la mayor serie de casos de oncocercosis importada descrita hasta la fecha

Field and laboratory comparative evaluation of a LAMP assay for the diagnosis of urogenital schistosomiasis in Cubal, Central Angola.

OBJECTIVE: To evaluate the performance of Rapid-Heat LAMPellet assay in field conditions for diagnosis of urogenital schistosomiasis in an endemic area in Cubal, Angola, and to assess the reproducibility in a reference laboratory. METHODS: A total of 172 urine samples from school-age children were tested for microhaematuria, microscopic detection of Schistosoma haematobium eggs and LAMP for DNA detection. Urine samples were stored in a basic equipped laboratory. Field-LAMP tests were performed with and without prior DNA extraction from urine samples, and the results were read by turbidity and by colour change. When field procedures were finished, samples were sent to a reference laboratory to be reanalysed by LAMP. RESULTS: A total of 83 of 172 (48.3%) were positive for microhaematuria, 87/172 (50.6%) were microscopy-positive for S. haematobium eggs detection, and 127/172 (73.8%) showed LAMP-positive results for detecting S. haematobium using purified DNA and 109/172 (63.4%) without prior DNA extraction. MacNemar's test showed a statistical significant relation between LAMP results and microscopy-detected S. haematobium infections and microhaematuria (P < 0.001 in both cases), respectively. When samples of purified DNA were reanalysed in a reference laboratory in Spain using the same LAMP methodology, the overall reproducibility achieved 72.1%. CONCLUSIONS: The ease of use, simplicity and feasibility demonstrated by LAMP assay in field conditions together with the acceptable level of reproducibility achieved in a reference laboratory support the use of LAMP assay as an effective test for molecular diagnosis of urogenital schistosomiasis in endemic remote areas.