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Wildlife can act as reservoir of different tick-borne pathogens of veterinary and zoonotic importance. To investigate the role of wild ruminants as reservoir of piroplasm infection, 28 red deer, 69 roe deer and 38 chamois from Northern Spain were examined by reverse line blot (RLB) hybridization. The survey detected a prevalence of 85.7% in red deer, 62.3% in roe deer and 28.9% in chamois. Four different piroplasms were identified: Theileria sp. OT3 (previously described in sheep) as the most prevalent (85.7% in red deer, 46.4% in roe deer and 26.3% in chamois); Theileria sp. 3185/02 (previously described in a red deer in Central Spain) more abundant in red deer (53.6%) than in roe deer (10.1%) but absent from chamois; Babesia divergens detected in 6 roe deer; Theileria ovis present in 1 chamois. Mixed infections (Theileria sp. OT3 and Theileria sp. 3185/02) were only found in red and roe deer. Sequencing analysis of the 18S rRNA gene confirmed the RLB results and showed 99.7% identity between Theileria sp. 3185/02 and T. capreoli, suggesting that they are the same species. Tick distribution and contact of wild ruminants with domestic animals are discussed in terms of piroplasm infection. The results suggest that a considerable number of wildlife ruminants are asymptomatic carriers that may serve as reservoirs of the infection posing a serious concern in terms of piroplasmosis control.

Adrenomedullin (AM) is a regulatory peptide whose involvement in tumour progression is becoming more relevant with recent studies. AM is produced and secreted by the tumour cells but also by numerous stromal cells including macrophages, mast cells, endothelial cells, and vascular smooth muscle cells. Most cancer patients present high levels of circulating AM and in some cases these higher levels correlate with a worst prognosis. In some cases it has been shown that the high AM levels return to normal following surgical removal of the tumour, thus indicating the tumour as the source of this excessive production of AM. Expression of this peptide is a good investment for the tumour cell since AM acts as an autocrine/paracrine growth factor, prevents apoptosis-mediated cell death, increases tumour cell motility and metastasis, induces angiogenesis, and blocks immunosurveillance by inhibiting the immune system. In addition, AM expression gets rapidly activated by hypoxia through a HIF-1α mediated mechanism, thus characterizing AM as a major survival factor for tumour cells. Accordingly, a number of studies have shown that inhibition of this peptide or its receptors results in a significant reduction in tumour progression. In conclusion, AM is a great target for drug development and new drugs interfering with this system are being developed.

A total of 562 questing adult ixodid ticks, collected during 2003-05 in 10 recreational mountain areas in northern Spain, were analysed for piroplasm infection. Reverse line blot (RLB) analysis using a panel of probes for 23 piroplasm species identified 16 different piroplasms, with an overall prevalence of 9.3%. Most were Theileria spp.-positive (7.7%), 3.0% were positive for Babesia spp. and 1.4% of ticks harboured both genera. Ixodes ricinus (Linnaeus, 1758), the most abundant tick in the vegetation, ranked third with regard to piroplasm infection prevalence (11.4%) after Rhipicephalus bursa (Canestrini & Fanzago, 1878) (16.0%) and Haemaphysalis punctata (Canestrini & Fanzago, 1878) (13.5%). Infection was detected in 6.2% of Dermacentor reticulatus (Fabricius, 1794) and in 1.1% of Haemaphysalis inermis (Birula, 1895), but was absent from Haemaphysalis concinna (Koch, 1844). Ixodes ricinus carried more piroplasm species (13), followed by H. punctata (10), D. reticulatus (8), R. bursa (3) and H. inermis (1). Although most of the positive ticks harboured a single infection (76.9%), mixed infections with two or three different piroplasm species were also detected (23.1%). The various tick-pathogen associations found are discussed and prevalences of infection in ticks are compared with previous results on piroplasms infecting animals in the same region.

A total of 691 questing adult ixodid ticks of the genera Ixodes, Haemaphysalis, Dermacentor, and Rhipicephalus were tested by polymerase chain reaction (PCR) and reverse line blot (RLB) for the presence of Anaplasma phagocytophilum, Coxiella burnetii, Borrelia spp., and spotted fever group (SFG) rickettsiae. Ticks were collected by blanket dragging during 2 sampling years (2003-2005) in 10 recreational areas in the Basque Country (Northern Spain). Adult ticks were collected every month of the year and eight different species were identified among which Ixodes ricinus was the most abundant and widespread. Three pathogens for humans, Borrelia burgdorferi, A. phagocytophilum, and C. burnetii, as well as rickettsiae of unknown pathogenicity were detected. The latter were identified as Rickettsia sp. RpA4/DnS14 by sequencing of the citrate synthase (gltA) gene. The infection rates varied from 0.1%-6.9%. DNA of A. phagocytophilum was detected mainly in I. ricinus, but also in Haemaphysalis punctata, H. concinna, and Rhipicephalus bursa. Coxiella burnetii was detected in only one specimen of H. punctata, and Borrelia spp. in eight ticks. Furthermore, PCR-RLB analysis specific for B. burgdorferi sensu lato detected one H. punctata with positive hybridization with the B. burgdorferi sensu stricto probe, and two I. ricinus positive for B. afzelii and B. garinii. SFG rickettsiae were the pathogens most frequently found, present in 48 of 97 D. reticulatus analyzed. Mixed infections were not found in any of the analyzed ticks. These results are compared and discussed with data obtained in previous studies carried out in the same and other regions.

Background To better understand the biology of COVID-19, we have explored the behavior of calcitonin gene-related peptide (CGRP), an angiogenic, vasodilating, and immune modulating peptide, in severe acute respiratory syndrome coronavirus 2 positive patients. Methods Levels of CGRP in the serum of 57 COVID-19 patients (24 asymptomatic, 23 hospitalized in the general ward, and 10 admitted to the intensive care unit) and healthy donors (n = 24) were measured by enzyme-linked immunosorbent assay (ELISA). In addition, to better understand the physiological consequences of the observed variations, we investigated by immunofluorescence the distribution of receptor activity modifying protein 1 (RAMP1), one of the components of the CGRP receptor, in autopsy lung specimens. Results CGRP levels were greatly decreased in COVID-19 patients (P < 0.001) when compared to controls, and there were no significant differences due to disease severity, sex, age, or comorbidities. We found that COVID-19 patients treated with proton pump inhibitors had lower levels of CGRP than other patients not taking this treatment (P = 0.001). RAMP1 immunoreactivity was found in smooth muscle cells of large blood vessels and the bronchial tree and in the airways´ epithelium. In COVID-19 samples, RAMP1 was also found in proliferating type II pneumocytes, a common finding in these patients. Conclusions The lower levels of CGRP should negatively impact the respiratory physiology of COVID-19 patients due to vasoconstriction, improper angiogenesis, less epithelial repair, and faulty immune response. Therefore, restoring CGRP levels in these patients may represent a novel therapeutic approach for COVID-19.

A new series of MMP2 inhibitors is described, following a fragment-based drug design approach. One fragment containing an azide group and a well known hydroxamate Zinc Binding Group in a α-sulfone, α-tetrahydropyrane scaffold, has been synthesized. Water-LOGSY, STD and competition-STD experiments indicate that this fragment binds to the active site of the enzyme. A click chemistry reaction was used to connect the azide to lipophilic alkynes selected to interact selectively with the S1' subunit of MMP2, as shown by docking and molecular dynamic experiments of the designed compounds. The most potent compounds 18 and 19 displayed an IC(50) of 1.4 and 0.3 nM against MMP2 respectively, and showed negligible activity towards MMP1 and MMP7, two metalloproteinases which have a shallow S1' subsite. Compound 18 also showed a promising selectivity profile against some antitarget metalloproteinases, such as MMP8, and considerably less activity against MMP14 (IC(50) = 65 nM), and MMP9 (IC(50) = 98 nM), other MMPs characterized by having a deep S1' pocket and, therefore, more similar to MMP2.