1. Investigación

Despite the enormous efforts made to achieve effective tools that fight against Staphylococcus aureus, the results have not been successful. This failure may be due to the absence of truly representative experimental models. To overcome this deficiency, the present work describes and immunologically characterizes the infection for 28 days, in an experimental low-dose (300 colony-forming units) intradermal model of infection in rabbits, which reproduces the characteristic staphylococcal abscess. Surprisingly, when mutant strains in the genes involved in virulence (JΔagr, JΔcoaΔvwb, JΔhla, and JΔpsmα) were inoculated, no strong effect on the severity of lesions was observed, unlike other models that use high doses of bacteria. The inoculation of a human rabbitized (FdltBr) strain demonstrated its capacity to generate a similar inflammatory response to a wild-type rabbit strain and, therefore, validated this model for conducting these experimental studies with human strains. To conclude, this model proved reproducible and may be an option of choice to check both wild-type and mutant strains of different origins.

Background: HTLV-1 infection is a neglected disease, despite producing neurological and lymphoproliferative severe illnesses and affect over 10 million people worldwide. Roughly 5% of HTLV-1 carriers develop Adult T-cell leukemia/lymphoma (ATLL), one of the most aggressive hematological malignancies. Methods: A national HTLV-1 register exists since 1989 in Spain, a non-endemic country with a large migrant flow from Latin America and Equatorial Africa, where HTLV-1 is endemic. The main features of all patients diagnosed with ATLL in Spain up to date are reported. Results: A total of 451 cases of HTLV-1 infection had been reported in Spain until the end of year 2022. ATLL had been diagnosed in 35 (7.8%). The current average incidence of ATLL in Spain is of two cases per year. Women represent 57% of ATLL patients. Mean age at diagnosis was 47 years-old. Roughly 57% were Latin Americans and 26% Africans. At diagnosis, the majority presented with acute or lymphoma clinical forms. Survival was shorter than one year in most of them. Mean HTLV-1 proviral load was significantly greater in ATLL patients than in asymptomatic HTLV-1 carriers (2,305 vs 104 copies/104 PBMC). HTLV-1 subtyping in 6 ATLL patients found the 1a transcontinental variant (n = 4) and the Japanese variant (n = 2). All ATLL patients were negative for HIV-1, did not develop HTLV-1-associated myelopathy and were not transplant recipients. Conclusion: The rate of ATLL is very low in Spain and mostly associated to migrants from HTLV-1 endemic regions. Given the poor clinical outcome of ATLL, HTLV-1 testing should be performed at least once in all migrants coming from HTLV-1 endemic countries and in natives who have lived in or had sex partners from such regions.

Background: HTLV-1 infection is a neglected disease. Over 10 million people are infected worldwide, with hot spots of high endemicity across all continents. Roughly 5% of HTLV-1 carriers develop HTLV-1-associated myelopathy (HAM), a progressive subacute neurological disabling disease. Methods: We report the main features of patients diagnosed with HAM up to date in Spain, a non-endemic country with a relatively high migrant flow from Latin America and Equatorial Africa, where HTLV-1 is endemic. Results: A total of 451 cases of HTLV-1 had been recorded in Spain until the end of year 2022. HAM had been diagnosed in 58 (12.9%). The current incidence is of 2-3 new cases per year. Women represent 76%. Mean age at diagnosis is 49 years-old. Nearly 60% are Latin Americans. Although sexual transmission is the most likely route of HTLV-1 acquisition, up to 6 individuals had been infected following solid organ transplantation. Rapid onset myelopathy developed in all but one of these transplant recipients from three HTLV-1-positive donors. HTLV-1 subtype 1a transcontinental was the only variant recognized in HAM patients. HTLV-1 proviral load was significantly greater in HAM patients than in asymptomatic HTLV-1 carriers (677 vs 104 HTLV-1 DNA copies/104 PBMC; p = 0.012). Symptom relief medications and physiotherapy have been the only treatment providing some benefit to HAM patients. Neither significant clinical nor virological efficacy was noticed using antiretrovirals in at least 9 HAM patients. Two thirds of HAM patients ended up in a wheelchair and with urinary/fecal sphincter incontinence. Conclusion: HAM is the most frequent clinical manifestation of HTLV-1 infection in Spain, a non-endemic country. Middle aged women migrants from Latin America are the most frequently affected. Two thirds end up in a wheelchair despite using antiretroviral therapy.

The aim of this study was to determine blood pressure (BP) and heart rate (HR) responses triggered during an isokinetic testing protocol in professional soccer players and compare cardiovascular parameters at completion of this isokinetic protocol with those during a treadmill test. Using purposive sampling, 63 professional soccer players were recruited. Cardiovascular responses were measured noninvasively during a bilateral testing protocol of knee flexion and extension. Treadmill ergospirometry following an incremental speed protocol was performed to analyze the same cardiovascular parameters at rest and at completion of this test. There were significant differences in diastolic blood pressure (DBP) and HR according to field position. The parameters presented high homogeneity at both competitive levels. Systolic blood pressure, mean arterial pressure, HR, and rate pressure product at completion of the treadmill test were significantly higher than those at completion of the isokinetic protocol. Intermittent isokinetic testing protocol of the knee triggers normal and safe BP and HR responses in healthy professional soccer players. The HR of the defenders was higher than those of the forwards and midfielders but was independent of the competitive level. The values of cardiovascular parameters at isokinetic protocol completion were lower than those during the treadmill test.