Molecular detection of Leishmania infantum in rats and sand flies in the urban sewers of Barcelona, Spain.

BACKGROUND: Classically, dogs have been considered to be the only reservoir of leishmaniasis in urban areas. However, in a previous study, we found a 33.3% prevalence of Leishmania infantum in the spleens of Norway rats (Rattus norvegicus) sampled in the underground sewer system of the city of Barcelona (Spain). The aim of the present study was to verify, using molecular methods, the potential reservoir role of these rats in the same sewer system. METHODS: A sensitive real-time PCR (qPCR) assay, DNA sequencing and phylogenetic analysis were carried out to identify and quantify the presence of L. infantum DNA in sand fly individuals captured in the same underground sewer system of Barcelona as in our previous study and in the spleens and ears of rats captured in the same sewer system. RESULTS: Leishmania infantum DNA was found in 14 of the 27 (51.9%) sand flies identified as Phlebotomus perniciosus, and 10 of the 24 (41.7%) rats studied were infected. Leishmania infantum was found in the spleens (70%) and in the ears (40%) of the infected rats. Quantitative results revealed the presence of high loads of L. infantum in the rats studied (> 3 × 106 parasites/g ear tissue) and among the sand flies (> 34 × 106 parasites in 1 individual). CONCLUSIONS: The molecular methods used in this study demonstrated a high prevalence of L. infantum in the underground sewer populations of both R. norvegicus and P. perniciosus. These results suggest that sewer rats, in addition to dogs, are likely to act as reservoirs of leishmaniasis in cities, where sewer systems seem to offer the ideal scenario for the transmission of leishmaniasis. Therefore, to achieve the WHO 2030 target on the elimination of leishmaniasis as a public health problem successfully, an efficient control strategy against leishmaniasis in rats and sand flies should be implemented, particularly in the sewer systems of urban areas of endemic countries.

One Health Approach to Zoonotic Parasites: Molecular Detection of Intestinal Protozoans in an Urban Population of Norway Rats, Rattus norvegicus, in Barcelona, Spain.

Rattus norvegicus, the brown or Norway rat, is the most abundant mammal after humans in urban areas, where they live in close proximity to people. Among rodent-borne diseases, the reservoir role of Norway rats of zoonotic parasites in cities has practically been ignored. Considering the parasitic diseases in the One Health approach, we intended to identify and quantify the zoonotic intestinal protozoans (ZIP) in an urban population of R. norvegicus in the city of Barcelona, Spain. We studied the presence of ZIP in 100 rats trapped in parks (n = 15) as well as in the city's sewage system (n = 85) in the winter of 2016/17. The protozoans were molecularly identified by means of a multiplex PCR (AllplexTM Gastrointestinal Panel-Parasite Assay). We also investigated the presence of co-infections among the species found. Four ZIP were identified, presenting significant prevalences in sewers, specifically Blastocystis (83.5%), Giardia duodenalis (37.7%), Cryptosporidium spp. (34.1%), and Dientamoeba fragilis (14.1%). Several co-infections among the detected ZIP were also detected. The reservoir role of ZIP that Norway rats play in cities as well as the role rats may play as sentinels of zoonotic parasites affecting humans in urban areas are strongly backed up by our findings. The increasing worldwide urbanization, climate change, and the COVID-19 pandemic are factors that are producing an increase in human-rat interactions. Our results should be considered a warning to the authorities to intensify rat control and surveillance in public health interventions.

Nicarbazin has no effect on reducing feral pigeon populations in Barcelona.

BACKGROUND: Nicarbazin is an anti-coccidial product sometimes used as a contraceptive to reduce the size of feral pigeon populations. However, its effectiveness in reducing pigeon population size in cities has caused some controversy. Here, we evaluate its effectiveness in the city of Barcelona. RESULTS: In 2017, the Barcelona City Council set 23 feeding stations with nicarbazin and ten with placebo (untreated corn). Censuses were undertaken before and after one year of treatment, within a 200-m radius around each feeder. We also censused 28 circles of 200 m radius distributed randomly 200 m from the feeders and 28 circles > 500 m from the feeders, which acted as controls. Population size across the whole city was also evaluated pre- and post treatment. We found that feral pigeon density did not change after one year of treatment, either in the circles around feeding stations with nicarbazin or in the areas around control stations at 200 and > 500 m from the feeders. Population size in placebo circles rose after a year by 10%. A pigeon census for the whole of Barcelona showed a 10% increase. CONCLUSION: Overall, our results indicate that the nicarbazin treatment had no effect on feral pigeon population size, and we advise against its use as a pigeon control method, at least in large cities.

Leishmaniasis in Norway Rats in Sewers, Barcelona, Spain.

We detected Leishmania infantum in 98 Norway rats (Rattus norvegicus) trapped in parks and sewers of Barcelona, Spain. The 84 rats from the sewers showed a prevalence of 33.3% and up to 2,272 estimated parasites. These results, in the most abundant potential reservoir in cities, is of public health concern.

New Litter Trap Devices Outperform Pitfall Traps for Studying Arthropod Activity.

Soil fauna play a key role in nutrient cycling and decomposition, and in recent years, researchers have become more and more interested in this compartment of terrestrial ecosystems. In addition, soil fauna can act as ecosystem engineers by creating, modifying, and maintaining the habitat for other organisms. Ecologists usually utilize live catches in pitfalls traps as a standard method to study the activity of epigeic fauna in addition to relative abundance. Counts in pitfall traps can be used as estimates of relative activity to compare among experimental treatments. This requires taking independent estimates of abundance (e.g., by sifting soil litter, mark-recapture), which can then be used as covariates in linear models to compare the levels of fauna activity (trap catches) among treatments. However, many studies show that the use of pitfall traps is not the most adequate method to estimate soil fauna relative abundances, and these concerns may be extensible to estimating activity. Here, we present two new types of traps devised to study activity in litter fauna, and which we call "cul-de-sac" and "basket traps", respectively. We experimentally show that, at least for litter dwellers, these new traps are more appropriate to estimate fauna activity than pitfall traps because: (1) pitfall traps contain 3.5× more moisture than the surrounding environment, potentially attracting animals towards them when environmental conditions are relatively dry; (2) cul-de-sac and basket traps catch ca. 4× more of both meso- and macrofauna than pitfall traps, suggesting that pitfall traps are underestimating activity; and (3) pitfall traps show a bias towards collecting 1.5× higher amounts of predators, which suggests that predation rates are higher within pitfall traps. We end with a protocol and recommendations for how to use these new traps in ecological experiments and surveys aiming at estimating soil arthropod activity.

First survey on zoonotic helminthosis in urban brown rats (Rattus norvegicus) in Spain and associated public health considerations.

The brown rat, Rattus norvegicus, with a worldwide distribution, is the most commensal species among synanthropic rodents, since its main habitat, in urban as well as in rural areas, is always linked to humans. Therefore, people living in close proximity to rodent populations can be exposed to infection. Whereas bacteria and viruses are the best known rat-associated zoonoses in urban environments, the role of brown rats as reservoirs for helminth parasites and the associated risk for humans are less well known. Specifically, this role has not been analyzed in Spain to date. A total of 100 R. norvegicus trapped in the sewage system (n = 85), and parks (n = 15) of Barcelona was examined. The overall prevalence of helminth infection was 85%. The helminths found were Hymenolepis nana (17%), H. diminuta (33%) (Cestoda), Calodium hepaticum (17%), Eucoleus gastricus (28%), Aonchotheca annulosa (12%), Trichosomoides crassicauda (7%), Nippostrongylus brasiliensis (46%), Heterakis spumosa (62%), Gongylonema neoplasticum (20%) (Nematoda) and Moniliformis moniliformis (6%) (Acanthocephala). Five of the ten helminth species are considered zoonotic parasites, with rats acting as reservoirs for human infection, i.e. H. nana, H. diminuta, C. hepaticum, G. neoplasticum and M. moniliformis. G. neoplasticum and M. moniliformis are reported for the first time in urban rats in Europe. H. nana, H. diminuta and C. hepaticum are the most widespread species in European cities. For H. nana and C. hepaticum, rats act as effective spreaders of the human infective stage (eggs). For H. diminuta, G. neoplasticum and M. moniliformis, rats act as indirect reservoirs of the zoonoses since the eggs shed by the rats are infective for their insect intermediate hosts only. Medical practitioners need to be made aware of the range of parasites carried by rats, as there is a realistic likelihood that ill health currently caused by rat infestations may be misdiagnosed.

Reducing the availability of food to control feral pigeons: changes in population size and composition.

BACKGROUND: As feeding by humans is one of the main food resources to pigeons (Columba livia), there is general agreement that public education that aims to reduce the food base may be the most feasible way to reduce pigeon abundance. However, except for the classic example of Basel, the method has rarely been tested or implemented. We provide results from a 1 year study in the city of Barcelona where we tested the effect of public education on pigeon population abundance and composition. RESULTS: The quantity of food provided by people to pigeons was significantly reduced during the study. Feral pigeon density was reduced by 40% in the two experimental districts, but no variation was detected in the control district. Detailed analyses in one of the districts showed that the reduction was mainly related to the reduction in food availability but not to culling. Pigeons captured at the end of the experiment were larger than at the start of the study, but body condition was reduced. CONCLUSION: Results show the effectiveness of public information to manage feral pigeon populations in a large city, and that control operations can exert important selection pressure on the population, leading to changes in population composition. © 2016 Society of Chemical Industry.

Prognostic value of X-chromosome inactivation in symptomatic female carriers of dystrophinopathy.

BACKGROUND: Between 8% and 22% of female carriers of DMD mutations exhibit clinical symptoms of variable severity. Development of symptoms in DMD mutation carriers without chromosomal rearrangements has been attributed to skewed X-chromosome inactivation (XCI) favouring predominant expression of the DMD mutant allele. However the prognostic use of XCI analysis is controversial. We aimed to evaluate the correlation between X-chromosome inactivation and development of clinical symptoms in a series of symptomatic female carriers of dystrophinopathy. METHODS: We reviewed the clinical, pathological and genetic features of twenty-four symptomatic carriers covering a wide spectrum of clinical phenotypes. DMD gene analysis was performed using MLPA and whole gene sequencing in blood DNA and muscle cDNA. Blood and muscle DNA was used for X-chromosome inactivation (XCI) analysis thought the AR methylation assay in symptomatic carriers and their female relatives, asymptomatic carriers as well as non-carrier females. RESULTS: Symptomatic carriers exhibited 49.2% more skewed XCI profiles than asymptomatic carriers. The extent of XCI skewing in blood tended to increase in line with the severity of muscle symptoms. Skewed XCI patterns were found in at least one first-degree female relative in 78.6% of symptomatic carrier families. No mutations altering XCI in the XIST gene promoter were found. CONCLUSIONS: Skewed XCI is in many cases familial inherited. The extent of XCI skewing is related to phenotype severity. However, the assessment of XCI by means of the AR methylation assay has a poor prognostic value, probably because the methylation status of the AR gene in muscle may not reflect in all cases the methylation status of the DMD gene.

Acute motor axonal neuropathy associated with anal carcinoma: Paraneoplastic neurological syndrome or coincidence?

AIM: Assessment of the association of an acute motor axonal neuropathy with a squamous cell anal carcinoma. BACKGROUND: Paraneoplastic neurologic syndromes are not a direct consequence of neither primary tumor nor its metastasis. They often parallel the course of the malignancy but may be the presenting sign of an occult cancer. Sometimes it is very difficult to distinguish if it is a paraneoplastic syndrome or just a coincidence. MATERIALS AND METHODS: We report a 60-year-old man that presented with an acute motor deficit of the four limbs. Clinical examination found a pure and severe motor deficit in the four limbs. No sensory abnormality was found and all motor nerves were unexcitable. Electromyography suggested the diagnosis of acute motor axonal neuropathy (AMAN). Four months after developing the AMAN, blood in the stool revealed anal carcinoma. The patient was treated with concurrent chemoradiotherapy. Radiation was given to the tumor and to the pelvis, including inguinal nodes, over a five-week period plus fluorouracil and mitomycin. We investigated the presence of antiganglioside antibodies as studies suggest that carcinomas can express antigens shared with Schwann cells. RESULTS: Anti-GM1 IgG antibodies were detected by an enzyme-linked immunosorbent assay method. Other antibodies, including antinuclear nucleoprotein antibody (anti-Hu), anti-Tr, anti-Ri, anti-CV2, anti-amphiphysin and anti-Yo, were negative. Clinical improvement of the motor state was observed at the fourth week of oncologic treatment. CONCLUSION: The presence of anti-GM1 IgG antibodies and the clinical improvement of the motor state after concurrent chemoradiotherapy lead us to believe there is an association between anal carcinoma and this severe impairment.

Depth profiling of high-energy hydrogen-implanted 6H-SiC.

The results of implanting silicon carbide with a 1-MeV proton beam at a dose of 1 x 10(17) cm(-2) are presented. Using high-resolution confocal Raman spectroscopy, we analyzed the depth profile of the implantation damage before and after thermal annealing. When it is applied to a high-refractive-index medium, such as SiC, this technique requires careful manipulation to ensure the correct interpretation of results. To this end we discuss a simple ray-tracking model that includes the effects of additional spherical aberration and of the Gaussian intensity profile of the excitation beam. In addition, infrared reflectance measurements show evidence of a well-defined step in the refractive-index profile at the expected implantation depth.

Tubular and interstitial expression of ICAM-1 as a marker of renal injury in IgA nephropathy.

BACKGROUND: The upregulated renal expression of intercellular adhesion molecule 1 (ICAM-1) is associated with glomerular and interstitial infiltration of leukocytes. AIM: To test the hypothesis that renal expression of ICAM-1 may be predictive in the highly variable IgA nephropathy (IgAN). METHODS: ICAM-1 (CD54) in tubular epithelium and interstitial leukocytes, macrophages (CD14), and T cells (CD3) were assessed using avidin-biotin-peroxidase in renal biopsy specimens from 45 patients with IgAN and from 29 patients with no glomerulonephritis. RESULTS: In IgAN, tubular ICAM-1+ was seen in 25 of 45 (55%) biopsy specimens, associated with glomerular hypercellularity, glomerulosclerosis involving less than 50% of the glomerular area, interstitial cellular infiltration, tubular atrophy, and proteinuria (U = 44, p = 0.005). Interstitial ICAM-1+ leukocytes were correlated with glomerulosclerosis involving less and more than 50% of the glomerular area, tubular atrophy, interstitial fibrosis, and serum creatinine concentration (r = 0.6343, p < 0.001). In patients with an increase of 50% in the serum creatinine concentration, interstitial ICAM-1+ leukocytes and CD14+ and CD3+ cells were significantly more numerous than in patients with a stable creatinine concentration. In patients with no glomerulonephritis, tubular ICAM-1+ was seen in 7 of 29 (24%) biopsy specimens, inversely correlated with the number of normal glomeruli and associated with glomerulosclerosis covering more than 50% of the glomerular area, tubular atrophy, and creatinine. CONCLUSIONS: Tubular and interstitial expression of ICAM-1 can be a marker of tubulointerstitial disturbance in IgAN. Interstitial ICAM-1 may be an adverse predictor of disease progression.

Expresión renal de la molécula de adhesión intercelular-1 (ICAM-1) en la nefropatía mesangial por depósitos de IgA. Un marcador de lesión tubulointersticial / Renal expression of ICAM-1 in IgA nephropathy. A marker of tubulointersticial injury

FUNDAMENTO: Conocer el significado clínicopatológico de la expresión renal de ICAM-1 en la nefropatía mesangial por IgA (NIgA). PACIENTES Y MÉTODO: Se identificó la expresión tubular e intersticial ICAM-1 (CD54) en 45 pacientes con NIgA y 29 pacientes con nefropatía no glomerulonefritis (NnoGN), analizándose su relación con la histología y la clínica en el momento de la biopsia renal y al cabo de 2,4 (2) (media [DE]) años en la NIgA y de 1,8 (1,5) años en la NnoGN. RESULTADOS: En 25 biopsias de NIgA (55 por ciento) se apreció expresión de ICAM-1 en el túbulo asociada a proliferación extracapilar (p < 0,05), así como esclerosis glomerular menor del 50 por ciento del área glomerular (p < 0,005), infiltración intersticial (p < 0,001) y atrofia tubular (p < 0,001). La proteinuria fue de 2,7 (1,5) g/24 h en los pacientes con expresión ICAM-1 en el túbulo y 1,5 (1,8) (p = 0,005) en los pacientes sin esta expresión. El número de leucocitos intersticiales ICAM-1 positivos fue de 234 (307)/mm2, y se correlacionó con la esclerosis glomerular en menos (r = 0,386; p < 0,05) y en más (r = 0,549; p = 0,01) del 50 por ciento del área glomerular, con la atrofia tubular (r = 0,442; p < 0,05); con la fibrosis intersticial (r = 0,405; p < 0,05) y con la creatinina (Cr) sérica (r = 0,6343; p < 0,001). Los pacientes con un incremento del 50 por ciento o superior de la Cr inicial presentaron 516 (360)/mm2 leucocitos intersticiales ICAM-1 positivos, frente a 66 (87,8)/mm2 p < 0,005) en los pacientes con Cr estable. En la NnoGN, 7 de las 29 biopsias (24 por ciento) presentaron ICAM-1 en el epitelio tubular. Hubo correlación inversa entre túbulo ICAM-1 positivos y glomérulos normales (r = -0,374; p < 0,05) y asociación con la esclerosis en más del 50 por ciento del área glomerular p < 0,005) y la atrofia tubular (p < 0,05). El número de leucocitos intersticiales ICAM-1 positivos fue de 191 (113)/mm2. Hubo correlación (r = 0,4356; p < 0,05) entre túbulo ICAM-1positivos y Cr en el momento de la biopsia. CONCLUSIONES: La expresión tubular e intersticial de ICAM-1 podría ser un marcador de lesión tubulointersticial en la NIgA. La presencia de ICAM-1 intersticial más que ICAM-1 tubular indicaría la progresión de la enfermedad en la NIgA (AU)