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The Gram-positive bacterium Lactococcus lactis, used for the production of cheeses and other fermented dairy products, falls victim frequently to fortuitous infection by tailed phages. The accompanying risk of dairy fermentation failures... more
The Gram-positive bacterium Lactococcus lactis, used for the production of cheeses and other fermented dairy products, falls victim frequently to fortuitous infection by tailed phages. The accompanying risk of dairy fermentation failures in industrial facilities has prompted in-depth investigations of these phages. Lactococcal phage Tuc2009 possesses extensive genomic homology to phage TP901-1. However, striking differences in the baseplate-encoding genes stimulated our interest in solving the structure of this host's adhesion device. We report here the X-ray structures of phage Tuc2009 receptor binding protein (RBP) and of a "tripod" assembly of three baseplate components, BppU, BppA, and BppL (the RBP). These structures made it possible to generate a realistic atomic model of the complete Tuc2009 baseplate that consists of an 84-protein complex: 18 BppU, 12 BppA, and 54 BppL proteins. The RBP head domain possesses a different fold than those of phages p2, TP901-1, an...
In 2012, a new betacoronavirus, Middle East respiratory syndrome coronavirus (MERS-CoV), was identified in humans. Several studies confirmed dromedary camels to be a potential reservoir and a source for human infection. Camels located on... more
In 2012, a new betacoronavirus, Middle East respiratory syndrome coronavirus (MERS-CoV), was identified in humans. Several studies confirmed dromedary camels to be a potential reservoir and a source for human infection. Camels located on the Canary Islands were included in those studies and ca 10% of them were positive for MERS-CoV-specific antibodies. However, these findings could not be correctly interpreted because epidemiological information was not provided. Thus, further investigations were necessary to clarify these results. A total of 170 camels were investigated in this survey, of which seven (4.1%) were seropositive by ELISA. Epidemiological information revealed that all seropositive camels had been imported from Africa 20 or more years prior. We conclude that seropositive camels had contact with MERS-CoV in Africa and that there is no shedding of the virus among camels or people around the farms on the Canary Islands. However, the presence of antibodies in the camel herds should be monitored.
Immunizing a camelid (camels and llamas) with soluble, properly folded proteins raises an affinity-matured immune response in the unique camelid heavy-chain only antibodies (HCAbs). The peripheral blood lymphocytes of the immunized animal... more
Immunizing a camelid (camels and llamas) with soluble, properly folded proteins raises an affinity-matured immune response in the unique camelid heavy-chain only antibodies (HCAbs). The peripheral blood lymphocytes of the immunized animal are used to clone the antigen-binding antibody fragment from the HCAbs in a phage display vector. A representative aliquot of the library of these antigen-binding fragments is used to retrieve single domain antigen-specific binders by successive rounds of panning. These single domain antibody fragments are cloned in tandem to generate manifold constructs (bivalent, biparatopic or bispecific constructs) to increase their functional affinity, to increase specificity, or to connect two independent antigen molecules.
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Trypanosoma evansi was first identified in the Canary Islands in 1997, and is still present in a small area of the Archipelago. To date, the disease has exclusively affected camel herds, and has not been detected in any other animal... more
Trypanosoma evansi was first identified in the Canary Islands in 1997, and is still present in a small area of the Archipelago. To date, the disease has exclusively affected camel herds, and has not been detected in any other animal hosts. However potential vectors of Trypanosoma evansi must be identified. One Nzi trap was placed on a camel farm located in the infected area for a period of one year. Two thousand five hundred and five insects were trapped, of which Stomoxys calcitrans was the sole hematophagous vector captured. Stomoxys calcitrans could be exclusively responsible for the transmission of Trypanosoma evansi among camels in the surveyed area, as other species do not seem to be infected by S. calcitrans in the presence of camels.
Two cases of uterine prolapse in dromedary camels in a herd with concomitant cases of white muscle disease are described. Serum selenium and glutathione peroxidase in whole blood were investigated in both patients and showed statistical... more
Two cases of uterine prolapse in dromedary camels in a herd with concomitant cases of white muscle disease are described. Serum selenium and glutathione peroxidase in whole blood were investigated in both patients and showed statistical difference compared with a control group. Results suggest that selenium deficiency could promote uterine prolapse in dromedary camels.
A rapid urinary iodide test was assessed in goats to validate its effectiveness in field conditions. The test provides a semiquantitative assessment of the iodine intake and could be valuable for animal population. Two hundred and... more
A rapid urinary iodide test was assessed in goats to validate its effectiveness in field conditions. The test provides a semiquantitative assessment of the iodine intake and could be valuable for animal population. Two hundred and forty-six dairy goats were randomized selected for this study. According to iodide content in urine, results were classified in three groups (30 μg/dL). These
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This communication presents a case of peromelia associated with brachydactyly and hyperphalangism in a newborn female goat. Absence and rudimentary distal phalanx were observed in hands and feet at X-ray examination. According to the... more
This communication presents a case of peromelia associated with brachydactyly and hyperphalangism in a newborn female goat. Absence and rudimentary distal phalanx were observed in hands and feet at X-ray examination. According to the Bell's classification [Bell, J., 1951. On brachydactyly and symphalangism. In: Penrose (Ed.), Treasury of Human Inheritance, vol. 5. Oxford University Press, Cambridge, pp. 1–30] the kid
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ABSTRACT
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The presence of given antigens in environmental samples (e.g. biodegradative enzymes) reports the quality and catalytic vigor of particular soils or aquatic ecosystems. In this context, we have developed the NanoPad system consisting of a... more
The presence of given antigens in environmental samples (e.g. biodegradative enzymes) reports the quality and catalytic vigor of particular soils or aquatic ecosystems. In this context, we have developed the NanoPad system consisting of a complete platform for isolation, amplification, and extracellular production of specific antibodies against antigens that diagnose the occurrence of protein markers in crude environmental samples. The workflow starts with the inoculation of camels (Camelus dromedarius) with various proteins (e.g. catabolic enzymes) for generating a phage display library of variable heavy-chain antibody H fragment (VHH ) domains that bind the different antigens. Instead of being subjected to a conventional panning, such a library is then probed with a Western-panning technique that allows direct isolation of specific binders of proteins blotted on membranes from polyacrylamide gels. Finally, VHH s are fused to the C-domain of hemolysin for secretion to the culture media as virtually pure dimeric proteins that can be used as a primary antibody without further processing. The value of NanoPad is shown with the selection of nanobodies for detection of biphenyl 2,3-dioxygenase, a key enzyme for biodegradation of polychlorinated biphenyls. The thereby generated anti-biphenyl 2,3-dioxygenase VHH s revealed the presence of this enzyme in the metaproteome of an oil refinery waste treatment plant.
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Fifteen two- to three-week-old kids, fed artificially with goats' milk from a dairy, were found to have polyarthritis. The most affected joints were the carpals, either unilaterally or bilaterally, and in some cases the tarsal... more
Fifteen two- to three-week-old kids, fed artificially with goats' milk from a dairy, were found to have polyarthritis. The most affected joints were the carpals, either unilaterally or bilaterally, and in some cases the tarsal joints. Mycoplasma putrefaciens was isolated from the joints which showed an acute fibrinopurulent arthritis. No clinical mastitis was detected in the dairy.
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An outbreak of Trypanosoma evansi infection that occurred in mainland Spain is described. The outbreak occurred on an equine and camel farm to which dromedary camels from an infected area of the Canary Islands had recently been... more
An outbreak of Trypanosoma evansi infection that occurred in mainland Spain is described. The outbreak occurred on an equine and camel farm to which dromedary camels from an infected area of the Canary Islands had recently been introduced. One of these camels developed clinical signs and T. evansi was discovered in a blood smear examination. The herd was evaluated in
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A new betacoronavirus-Middle East respiratory syndrome coronavirus (MERS-CoV)-has been identified in patients with severe acute respiratory infection. Although related viruses infect bats, molecular clock analyses have been unable to... more
A new betacoronavirus-Middle East respiratory syndrome coronavirus (MERS-CoV)-has been identified in patients with severe acute respiratory infection. Although related viruses infect bats, molecular clock analyses have been unable to identify direct ancestors of MERS-CoV. Anecdotal exposure histories suggest that patients had been in contact with dromedary camels or goats. We investigated possible animal reservoirs of MERS-CoV by assessing specific serum antibodies in livestock. We took sera from animals in the Middle East (Oman) and from elsewhere (Spain, Netherlands, Chile). Cattle (n=80), sheep (n=40), goats (n=40), dromedary camels (n=155), and various other camelid species (n=34) were tested for specific serum IgG by protein microarray using the receptor-binding S1 subunits of spike proteins of MERS-CoV, severe acute respiratory syndrome coronavirus, and human coronavirus OC43. Results were confirmed by virus neutralisation tests for MERS-CoV and bovine coronavirus. 50 of 50 (1...
Two cases of urinary retention in male dromedaries due to silica uroliths are presented. The animals were urethrostomized and one dromedary was euthanized 7 months later due to urethrostomy obstruction. The estimated daily intake of... more
Two cases of urinary retention in male dromedaries due to silica uroliths are presented. The animals were urethrostomized and one dromedary was euthanized 7 months later due to urethrostomy obstruction. The estimated daily intake of silica was 84.44 g. Silica, calcium, phosphorus and pH in urine were determined in healthy animals from the same farms, and the following values were obtained: 174.78 +/- 3.46 mg/l (silica), 41.48 +/- 4.82 mg/l (calcium), 20.4 +/- 3.6 mg/l (phosphorus) and pH 8.2, respectively. Possible causes of urolithiasis were the early castration of the animals and the fact that salt was not added to the diet. To our knowledge, this is the first description of silica urolithiasis in the dromedary camel.
According to several authors, Trypanosoma evansi is a monomorphic trypanosome found exclusively in slender intermediate forms, although additional studies have revealed that many strains present stumpy forms on rare occasions. In a recent... more
According to several authors, Trypanosoma evansi is a monomorphic trypanosome found exclusively in slender intermediate forms, although additional studies have revealed that many strains present stumpy forms on rare occasions. In a recent T. evansi outbreak in mainland Spain, several atypical forms were observed in blood smear examinations. Molecular procedures were then necessary to confirm the causal agent. Morphological and biometric measures were taken to characterize the different forms of T. evansi. In contrast to published information, the results of this study would indicate that biometrically distinct T. evansi could also be found in the same farm and even in the same animal species. These data could be useful for many trypanosomes endemic areas of the world where molecular methods are not commonly available.
Trypanosoma evansi is the most widely spread of the pathogenic African trypanosomes of animals. The disease (surra) was first diagnosed in the Canary Islands in a dromedary camel in 1997; thus, a control plan was implemented achieving the... more
Trypanosoma evansi is the most widely spread of the pathogenic African trypanosomes of animals. The disease (surra) was first diagnosed in the Canary Islands in a dromedary camel in 1997; thus, a control plan was implemented achieving the eventual eradication of T. evansi from most of the infected areas in the Archipelago. However, a little area remains still infected despite the use of the same control measures. To evaluate possible reservoirs in the area a representative sample of domestic ruminants was examined by serological, parasitological and molecular tests. Of a total of 1228 ruminants assessed, 61 (5%) were serologically positive (7 cattle, 21 goats, 33 sheep), but T. evansi could be demonstrated in none of them. According to FreeCalc assessment, cattle and goat populations would be free from disease; however, the results from sheep are not adequate to conclude that the population would be free from disease. As a conclusion, surveillance must be exercised on ruminant farms in the surroundings of the infected area in order to evaluate the possible extension of the disease and their potential role as reservoirs of T. evansi.
In scientific literature, a small amount of information is found concerning mycoplasmosis in camel species. Mycoplasma (M.) arginini, Acholeplasma (A.) laidlawii, and Acholeplasma oculi have been reported to be isolated from these host... more
In scientific literature, a small amount of information is found concerning mycoplasmosis in camel species. Mycoplasma (M.) arginini, Acholeplasma (A.) laidlawii, and Acholeplasma oculi have been reported to be isolated from these host species. Serologically positive results have been reported for Mycoplasma mycoides subsp. mycoides SC type, Mycoplasma capricolum subsp. capripneumoniae, and M. mycoides subsp. capri. The aims of this study were to detect, isolate, and identify mycoplasmas from camels (Camelus dromedarius). Initially, saliva and ear smears plus conjunctival and vaginal secretions were taken from five female animals, but only conjunctival secretions in three male animals, all belonging to the same farm. An unknown mycoplasma was isolated from one of the vagina samples. Additionally, another unknown and uncultured mycoplasma was detected with molecular biology in the same sample. In the second stage, 23 vaginal secretions were taken from the same farm plus another secre...
In 2008, Trypanosoma evansi was detected on a camel farm in mainland Spain. The animals were isolated, confined in a closed stable, and treated twice with melarsamine (Cymelarsan(®), Merial, Lyon, France) with an interval of 1 month.... more
In 2008, Trypanosoma evansi was detected on a camel farm in mainland Spain. The animals were isolated, confined in a closed stable, and treated twice with melarsamine (Cymelarsan(®), Merial, Lyon, France) with an interval of 1 month. Clinical and laboratory examinations by means of parasitological, serological, and molecular procedures (polymerase chain reaction (PCR)) were carried out regularly for 6 years. After the treatment, all parasitemic camels were cleared of parasites, and in the seropositive camels a progressive decrease in antibody levels was observed, with complete disappearance of antibodies between 15 and 21 months, except in one animal which showed doubtful Ag-Ab reaction at 21 months post treatment. In the next assessment, 6 months later, the diagnostic tests conducted on all animals had a negative result. The diagnostic and therapeutic tools recently developed against T. evansi will evidence new and alternative approaches after the parasite is detected, particularly if outbreak occurs in geographically localized areas in territories free of the disease.

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