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BackgroundApproximately 50% of patients who receive anti-CD19 CAR-T cells relapse, and new immunotherapeutic targets are urgently needed. We recently described CD72 as a promising target in B-cell malignancies and developed nanobody-based CAR-T cells (nanoCARs) against it. This cellular therapy design is understudied compared with scFv-based CAR-T cells, but has recently become of significant interest given the first regulatory approval of a nanoCAR in multiple myeloma.MethodsWe humanized our previous nanobody framework regions, derived from llama, to generate a series of humanized anti-CD72 nanobodies. These nanobody binders were inserted into second-generation CD72 CAR-T cells and were evaluated against preclinical models of B cell acute lymphoblastic leukemia and B cell non-Hodgkin's lymphoma in vitro and in vivo. Humanized CD72 nanoCARs were compared with parental ("NbD4") CD72 nanoCARs and the clinically approved CD19-directed CAR-T construct tisangenlecleucel. RNA-sequencing, flow cytometry, and cytokine secretion profiling were used to determine differences between the different CAR constructs. We then used affinity maturation on the parental NbD4 construct to generate high affinity binders against CD72 to test if higher affinity to CD72 improved antitumor potency.ResultsToward clinical translation, here we humanize our previous nanobody framework regions, derived from llama, and surprisingly discover a clone ("H24") with enhanced potency against B-cell tumors, including patient-derived samples after CD19 CAR-T relapse. Potentially underpinning improved potency, H24 has moderately higher binding affinity to CD72 compared with a fully llama framework. However, further affinity maturation (KD

Rhodopsin is a prototypical G protein-coupled receptor (GPCR) critical for vertebrate vision. Research on GPCR signaling states has been facilitated using llama-derived nanobodies (Nbs), some of which bind to the intracellular surface to allosterically modulate the receptor. Extracellularly binding allosteric nanobodies have also been investigated, but the structural basis for their activity has not been resolved to date. Here, we report a library of Nbs that bind to the extracellular surface of rhodopsin and allosterically modulate the thermodynamics of its activation process. Crystal structures of Nb2 in complex with native rhodopsin reveal a mechanism of allosteric modulation involving extracellular loop 2 and native glycans. Nb2 binding suppresses Schiff base deprotonation and hydrolysis and prevents intracellular outward movement of helices five and six - a universal activation event for GPCRs. Nb2 also mitigates protein misfolding in a disease-associated mutant rhodopsin. Our data show the power of nanobodies to modulate the photoactivation of rhodopsin and potentially serve as therapeutic agents for disease-associated rhodopsin misfolding.

This paper presents the results of a study on the isotopic ecology of guanacos in central western Argentina. We examine the historical population ecology of guanacos using stable isotope analysis of bone collagen from pre-Hispanic and modern guanaco populations (n = 129), considering variability in two ecoregions: the Monte hot desert and the Andean-Patagonian cold desert. Our study addresses the consistency of guanaco diets over time, evaluating palaeoecology to provide information for conservation of this taxon. We found significant differences in isotopic niche size between modern and archaeological guanacos. When analyzed by ecoregion, there were significant differences in niche size through time, indicating that guanacos had distinctive dietary habits and occupied different ecological niches across the ecoregions. Comparing Standard Ellipse Areas (SEA) through time and across space, we observed that the archaeological SEA for guanacos is smaller than its modern counterpart in the Andean-Patagonia ecoregion. Conversely, in Monte, the archaeological SEA is larger than the one established for modern samples. The contrast between pre-Hispanic and modern populations highlight the impact of human activity and conservation efforts on the distribution and ecology of guanacos. These findings have important implications for understanding guanaco ecology with consequences for conservation policies. [ABSTRACT FROM AUTHOR]

This paper aims to describe a case of trombiculosis in llamas from the Puna region of Argentina caused by Eutrombicula cochinocaensis. Trombiculosis is a parasitic infestation caused by the larval form of trombiculid mites, commonly known as chigger mites. Six adult llamas out of eighteen (33%) were infested and showed dermatitis, hyperemia, and crusts together with an orange-dotted pattern. The chigger mites were found mainly in the hind limbs and the abdomen. Microscopic identification of E. cochinocaensis was made by phase-contrast microscopy. Then, a histopathological study of the affected animals' skin was performed. Histological findings included dermatitis withmainly lymphocytic infiltrate, pustules, crusts, hyperkeratosis, and the mites' stylostomes in the dermis and epidermis. This is the first report of trombiculosis caused by E. cochinocaensis in llamas from Argentina. Mites of the family Trombiculidae are vectors of certain diseases to humans and animals and are therefore of sanitary and productive importance. [ABSTRACT FROM AUTHOR]

The increased availability of quality genomic data has greatly improved the scope and resolution of our understanding of the recent evolutionary history of wild species adapted to extreme environments and their susceptibility to anthropogenic impacts. The guanaco (Lama guanicoe), the largest wild ungulate in South America, is a good example. The guanaco is well adapted to a wide range of habitats, including the Sechura Desert, the high Andes Mountains to the north, and the extreme temperatures and conditions of Navarino Island to the south. Guanacos also have a long history of overexploitation by humans. To assess the evolutionary impact of these challenging habitats on the genomic diversity, we analyzed 38 genomes (∼10 to 16×) throughout their extensive latitudinal distribution from the Sechura and Atacama Desert to southward into Tierra del Fuego Island. These included analyses of patterns of unique differentiation in the north and geographic region further south with admixture among L. g. cacsilensis and L. g. guanicoe. Our findings provide new insights on the divergence of the subspecies ∼800,000 yr BP and document two divergent demographic trajectories and to the initial expansion of guanaco into the more southern portions of the Atacama Desert. Patagonian guanacos have experienced contemporary reductions in effective population sizes, likely the consequence of anthropogenic impacts. The lowest levels of genetic diversity corresponded to their northern and western limits of distribution and some varying degrees of genetic differentiation. Adaptive genomic diversity was strongly linked with environmental variables and was linked with colonization toward the south followed by adaptation. [ABSTRACT FROM AUTHOR]

Gastrointestinal adenocarcinomas are often reported in South American camelids (SAC). We describe here cases of gastroduodenal adenocarcinoma in an adult alpaca (Vicugna pacos) and a llama (Llama glama); both SACs were anorectic and lethargic before death. At autopsy, a prominent and firm caudal C3-pyloric-duodenal junction with stricture and ulceration was present in both animals, as were hemorrhages in various organs and hydrothorax. Microscopically, scattered nests, cords, and tortuous acini of neoplastic epithelial cells were embedded in desmoplastic stroma and invaded the submucosa and muscle layers of the gastroduodenal junction. The mucosa was necrotic, with gram-negative rods in the alpaca and colonies of gram-positive cocci in the llama. No tumor metastases were observed. The neoplastic cells immunolabeled for pancytokeratin. Escherichia coli was isolated from the alpaca and Streptococcus lutetiensis from the llama; septicemia was the cause of death in both animals. Although adenocarcinomas arising from gastric compartments and intestinal segments have been reported in SACs, adenocarcinoma of the caudal C3-pyloric-duodenal junction has not been reported previously in these species, to our knowledge. [ABSTRACT FROM AUTHOR]

Stable isotope studies have revolutionised our understanding of food webs, subsistence, mobility and their change through time. In the Andes, dietary stable isotopic studies have often focused on timing the adoption of maize as a staple food and identifying camelid pastoralism in selected valleys of the Pacific coast. Few studies have focused on highland societies and understanding pastoralist communities in particular, but the underlying assumption has been that camelid herders had essentially narrow and specialised diets. To evaluate this assertion, we analyzed dietary carbon and nitrogen stable isotopes of 27 human and 23 faunal specimens from nine archaeological sites located in the Central Altiplano of Bolivia supported by 27 radiocarbon dates. Our results suggest important diversity characterised both human and animal isotopic ecology between 1300 BCE and 1200 CE. The collected data also demonstrates that maize was not regularly consumed, suggesting interregional food exchange between this region of the Altiplano and its neighboring lowland inter-Andean valleys likely postdated 1100 CE. Consistent with reliance on cultivated crops such as chenopods and tubers and wild fauna including rodents, birds and fish, early camelid herders in the Andean Central Altiplano relied on a generalised form of pastoralism. [ABSTRACT FROM AUTHOR]

ABSTRACT: Background: The global spread of extended-spectrum β-lactamase (ESβL)-producing Escherichia coli has been considered a One Health issue that demands continuous genomic epidemiology surveillance in humans and non-human hosts. Objectives: To report the occurrence and genomic data of ESβL-producing E. coli strains isolated from South American llamas inhabiting a protected area with public access in the Andean Highlands of Peru. Methods: Two ESβL-producing E. coli strains (E. coli L1LB and L2BHI) were identified by MALDI-TOF. Genomic DNAs were extracted and sequenced using the Illumina NextSeq platform. De novo assembly was performed by CLC Genomic Workbench and in silico prediction was accomplished by curated bioinformatics tools. SNP-based phylogenomic analysis was performed using publicly available genomes of global E. coli ST10. Results: Escherichia coli L1LB generated a total of 4 000 11 and L2BHI a total of 4 002 54 paired-end reads of ca.164 × and ca. 157 ×, respectively. Both E. coli strains were assigned to serotype O8:H4, fimH41, and ST10. The blaCTX-M-65 ESβL gene, along with other medically important antimicrobial resistance genes, was predicted. Broad virulomes, including the presence of the astA gene, were confirmed. The phylogenomic analysis revealed that E. coli L1LB and L2BHI strains are closely related to isolates from companion animals and human hosts, as well as environmental strains, previously reported in North America, South America, Africa, and Asia. Conclusion: Presence of ESβL-producing E. coli ST10 in South American camelids with historical and cultural importance supports successful expansion of international clones of priority pathogens in natural areas with public access.

A weak dromedary calf with signs of prematurity was born in April of 2023 to a healthy multiparous camel with a good body condition. The calf was diagnosed strongly positive to Trypanosoma evansi by haematocrit centrifugation technique (immediately after birth). The mother at that time was asymptomatic and negative by haematocrit centrifugation technique and PCR of blood. Indirect ELISA of the calf's serum before colostrum ingestion showed negligible levels of antibodies. However, 12 hours after colostrum ingestion and without any treatment, the levels of antibodies increased significantly, which coincided with negative haematocrit centrifugation technique. This indicates a possible role of colostral antibodies in neutralising the trypanosomes in the calf's blood. Examination of the placenta showed placentitis, and PCR confirmed a positive result for Trypanosoma nucleic acid. The importance of vertical transmission in maintaining the infection in a herd is discussed, as well as the role of colostrum in decreasing calf mortalities due to trypanosomosis. [ABSTRACT FROM AUTHOR]

A 4‐year‐old, female alpaca developed necrotising myositis caused by Clostridium difficile and Clostridium clostridioforme, a clostridia spp. previously unknown to affect camelids, shortly after an event of grain overload. The affected leg was amputated due to the aggressive necrosis. This case reports an interesting sequelae of grain overload in camelids, as well as highlights the presence of bacteria not previously known to be pathogenic in camelids and that may need to be further considered in the list of pathogens of South American camelids. [ABSTRACT FROM AUTHOR]

Since their discovery in the 1990s, heavy chain antibodies have garnered significant interest in the scientific community. These antibodies, found in camelids such as llamas and alpacas, exhibit distinct characteristics from conventional antibodies due to the absence of a light chain in their structure. Furthermore, they possess a single antigen-binding domain known as VHH or Nanobody (Nb). With a small size of approximately 15 kDa, these Nbs demonstrate improved characteristics compared to conventional antibodies, including greater physicochemical stability and enhanced biodistribution, enabling them to bind inaccessible epitopes more effectively. As a result, Nbs have found numerous applications in various medical and veterinary fields, particularly in diagnostics and therapeutics. Advances in biotechnology have made the production of recombinant antibodies feasible and compatible with large-scale manufacturing. Through the construction of immune phage libraries that display VHHs and subsequent selection through biopanning, it has become possible to isolate specific Nbs targeting pharmaceutical targets of interest, such as viruses. This review describes the processes involved in nanobody production, from hyperimmunization to purification, with the aim of their application in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

A two-week-old female llama cria was brought to the UC Davis Large Animal Hospital for evaluation of a cardiac murmur and suspected syncopal episodes. A grade IV/VI left basilar continuous murmur was present on cardiac auscultation. Echocardiography revealed a left-to-right shunting patent ductus arteriosus (PDA), mild left ventricular enlargement, scant pericardial effusion, and a suspected persistent left cranial vena cava. The PDA was successfully closed with an Amplatz canine duct occluder. Mild mitral regurgitation was present on echocardiography performed 7 d following PDA occlusion. No syncopal episodes were observed in hospital prior to or following PDA occlusion. At approximately 1 mo following PDA closure, a grade I/VI left apical systolic murmur was present and the cria's body condition was improved. Key clinical message: Patent ductus arteriosus closure is achievable in New World camelids using interventional cardiology which provides a minimally invasive treatment option for valuable or companion animals. Since interventional cardiac catheterization is commonly performed in small animal species, veterinary cardiologists are well-equipped to apply these skills to camelids.

Several plants that contain indolizidine alkaloids, including swainsonine, are toxic to livestock, causing dysfunctional lysosomes and storage disease. Swainsonine induces a neurovisceral disease, known as locoism, in sheep, goats, and cattle, which occurs in several parts of the world, including, but not limited to, the western United States, China, and parts of Australia. In South America, locoism has been described in the Andean region of Argentina affecting sheep, cattle, and llamas. Intoxication by consumption of Astragalus punae was suspected in 4 llamas in Jujuy Province, northwestern Argentina. The grazing area contained abundant specimens of A. punae. The clinical course was ~15 d, and included moderate ataxia, incoordination of hindlimbs, and progressive loss of body condition. Microscopically, fine cytoplasmic microvacuolation was observed in the proximal convoluted renal tubules. Ultrastructurally, these changes consisted of severely dilated lysosomes. Swainsonine was detected in stem and leaf samples of A. punae at a concentration of 0.06%. Based on clinical history and signs, histologic and ultrastructural changes, and plant analysis, a diagnosis of swainsonine toxicosis caused by consumption of A. punae was made, which has not been reported previously, to our knowledge.

Camelids are the only living representatives of the Suborder Tylopoda, and present a unique set of osteo‐myological masticatory features, differing from all other extant euungulates. They combine selenodont dentition and rumination with a fused symphysis, and roughly plesiomorphic muscle proportions. Despite its potential relevance as an euungulate model in comparative anatomy studies, the available data is strikingly scarce. The present study represents the first description of the masticatory muscles of a Lamini, analyzing the functional morphology of Lama glama and other camelids in a comparative framework. Both sides of the head of three adult specimens from Argentinean Puna were dissected. Descriptions, illustrations, muscular maps, and weighing of all masticatory muscles were performed. Some facial muscles are also described. The myology of llamas confirms that camelids possess relatively large temporalis muscles, with Lama being less extreme than Camelus. This plesiomorphic feature is also recorded in suines and some basal euungulates. Conversely, the direction of the fibers of the M. temporalis is mainly horizontal, resembling grinding euungulates such as equids, pecorans, and some derived suines. Although the M. masseter of camelids and equids do not reach the particularly modified configuration of pecorans, in which it is rostrally extended and arranged horizontally, the posterior sectors of Mm. masseter superficialis and pterygoideus medialis have acquired relatively horizontal disposition in the former lineages, suitable for protraction. The pterygoidei complex presents several bundles, and its relative size is intermediate between suines and derived grinding euungulates. The whole masticatory muscles are relatively light when compared to jaw weight. The evolution of the masticatory muscles and chewing of camelids implied that grinding abilities were reached with less extreme modifications of the topography and/or proportions than pecoran ruminants and equids. A relatively large M. temporalis recruited as a powerful retractor during the power stroke is a key feature of camelids. The relaxed pressure on chewing derived from the acquisition of rumination explains the slenderer build masticatory musculature of camelids compared to other euungulates except ruminants. [ABSTRACT FROM AUTHOR]

An 11-y-old hembra alpaca was admitted because of cerebellar and vestibular signs, dysphagia, and aspiration pneumonia; without clinical improvement following empirical therapy, the patient was euthanized. On autopsy, a neoplasm was found incorporating the right vestibulocochlear nerve at the level of the acoustic meatus. Histologically, the mass was composed of a multiphasic primitive cell population associated with a dense fibrous stroma and enveloping a remnant ganglion and nerve bundles. Patterns included dense ribbons and cords of embryonal neuroepithelial cells admixed with loosely defined interlacing spindle cells. The embryonal cells had angular cell profiles with variable amounts of lightly basophilic cytoplasm, ovoid-to-irregular nuclei, and an open chromatin pattern with a typically inapparent nucleolus. Necrosis was not evident, and there was 1 mitotic figure per 2.37 mm2. The entire mass was infiltrated by small numbers of lymphocytes and plasma cells. Immunohistochemistry (IHC) revealed strong and diffuse cytoplasmic immunolabeling for vimentin, microtubule-associated protein-2, protein gene product 9.5, and synaptophysin; ~50% immunolabeling for cytokeratin AE1/3; sporadic OLIG2 and S100 immunolabeling; and absent glial fibrillary acidic protein immunolabeling. Based on the histologic pattern and the IHC results, our diagnosis was a poorly differentiated embryonal tumor with ependymal differentiation associated with the vestibulocochlear nerve. [ABSTRACT FROM AUTHOR]

Since their discovery in the 1990s, heavy chain antibodies have garnered significant interest in the scientific community. These antibodies, found in camelids such as llamas and alpacas, exhibit distinct characteristics from conventional antibodies due to the absence of a light chain in their structure. Furthermore, they possess a single antigen-binding domain known as VHH or Nanobody (Nb). With a small size of approximately 15 kDa, these Nbs demonstrate improved characteristics compared to conventional antibodies, including greater physicochemical stability and enhanced biodistribution, enabling them to bind inaccessible epitopes more effectively. As a result, Nbs have found numerous applications in various medical and veterinary fields, particularly in diagnostics and therapeutics. Advances in biotechnology have made the production of recombinant antibodies feasible and compatible with large-scale manufacturing. Through the construction of immune phage libraries that display VHHs and subsequent selection through biopanning, it has become possible to isolate specific Nbs targeting pharmaceutical targets of interest, such as viruses. This review describes the processes involved in nanobody production, from hyperimmunization to purification, with the aim of their application in the pharmaceutical industry.

The Lake Titicaca basin was one of the major centers for cultural development in the ancient world. This lacustrine environment is unique in the high, dry Andean altiplano, and its aquatic and terrestrial resources are thought to have contributed to the florescence of complex societies in this region. Nevertheless, it remains unclear to what extent local aquatic resources, particularly fish, and the introduced crop, maize, which can be grown in regions along the lakeshores, contributed to facilitating sustained food production and population growth, which underpinned increasing social political complexity starting in the Formative Period (1400 BCE to 500 CE) and culminating with the Tiwanaku state (500 to 1100 CE). Here, we present direct dietary evidence from stable isotope analysis of human skeletal remains spanning over two millennia, together with faunal and floral reference materials, to reconstruct foodways and ecological interactions in southern Lake Titicaca over time. Bulk stable isotope analysis, coupled with compound-specific amino acid stable isotope analysis, allows better discrimination between resources consumed across aquatic and terrestrial environments. Together, this evidence demonstrates that human diets predominantly relied on C3 plants, particularly quinoa and tubers, along with terrestrial animals, notably domestic camelids. Surprisingly, fish were not a significant source of animal protein, but a slight increase in C4 plant consumption verifies the increasing importance of maize in the Middle Horizon. These results underscore the primary role of local terrestrial food resources in securing a nutritious diet that allowed for sustained population growth, even in the face of documented climate and political change across these periods.

This document is an editorial published in Frontiers in Veterinary Science titled "Current knowledge on camelids infectious and parasitic diseases." The editorial highlights the importance of studying diseases in camelids, including Old World camels (dromedary and Bactrian camels) and New World camels (llama, alpaca, guanaco, vicuna). The editorial summarizes 10 articles on various infectious and parasitic diseases in camelids, including tick infestation, intestinal protozoan parasites, neosporosis, eimeriosis, mastitis, tuberculosis, and zoonotic diseases. The articles provide insights into the prevention, control, and understanding of these diseases to ensure the well-being of camels and mitigate potential health risks to humans. [Extracted from the article]

The bacterial community of the forestomach plays important roles in the digestive processes of ruminants and pseudo-ruminants. To investigate the rumen microbiota in the pseudo-rumen of camels (Camelus dromedarius) raised in a natural environment in Algeria, bacterial diversity was determined from 25 dromedaries using 16S rRNA gene amplicon sequencing. A total of 25 bacterial phyla were identified across all the samples, including Firmicutes (close to 85℅), Bacteroidetes (about 12%) and to a lesser extent Proteobacteria (< 1%), with these three phyla together accounting for more than 97% of all sequences. Our results are consistent with previous observations of bacterial communities diversity and abundancy in the rumen or pseudo-rumen of other ruminant species (either domestic or wild), although the abundance of individual bacterial phyla showed remarkably high disparities. Links between the richness and type of diet and the composition of the rumen microbiome are discussed.

Dromedary camels are the preferable livestock species in the arid and semi-arid regions of the world. Most of the world’s camel populations are managed under a subsistence/extensive system maintained by migratory pastoralists but intensification is getting more frequent. Even though recently the welfare of camels has been receiving more attention, in many countries there are no regulations to protect their health and welfare. The objectives of this article were to explore the main research topics related to camel welfare, their distribution over time and to highlight research gaps. A literature search was performed to identify records published in English from January 1980 to March 2023 on Dromedary camel welfare via Scopus®, using “Camel welfare,” “Camel behaviour,” “She-camel” and “Camel management” as search words. A total of 234 records were retained for analysis after automatic and manual screening procedures. Descriptive statistics, text mining (TM) and topic analysis (TA) were performed. The result shows that even though there were fluctuations between years, records on camel welfare have increased exponentially over time. Asia was the region where most of the corresponding authors were located. The first five most frequent words were, “milk,” “calv,” “behaviour,” “femal,” and “breed,” the least frequent word was “stabl.” TA resulted in the five most relevant topics dealing with “Calf management and milk production,” “Camel health and management system,” “Female and male reproduction,” “Camel behaviour and feeding,” and “Camel welfare.” The topics that contained the oldest records were “female and male reproduction” and “camel health and management system” (in 1980 and 1983, respectively), while the topic named “camel behaviour and feeding” had the first article published in 2000. Overall, even though topics related to camel behaviour and welfare are receiving more attention from academia, research is still needed to fully understand how to safeguard welfare in Dromedary camels.

Abstract The Argentinian Ministry of Environment has approved the translocation of 45 guanacos from Southern Patagonia to the Pampas region, a distance of 1500 km, as the initial phase toward future translocations into a National Park located in the Chaco region, another 1600 km further North. This decision raises concerns about the technical and ethical aspects of the translocation. Firstly, there is a lack of proper evaluation and scientific evidence to support the need, opportunity, and feasibility of this translocation. The guanaco population is currently over one million and is increasing, and genetic differences exist among local populations. The translocation could produce anthropogenic‐driven admixed populations, leading to genetic swamping and disrupting evolutionary processes. Second, there are ethical conflicts around managing wild species populations that prioritize private objectives and disregard local, publicly funded science. Rewilding projects require a deep understanding of interacting ecosystem processes, and of the socio‐economic context. This management decision violates guiding principles for rewilding and should have followed proper scientific evaluation and transparent local consultation.

Regular and intensive links between populations in the Lower Paraná and the Southern Andes, the Central Hills, and the Santiagueña Plains are evident in the most recent period of the Late Holocene. In this article, we summarize the small-scale and large-scale trade and exchange among these regions, which included not only material objects, such as metal, rocks, and shells, but also animals and intangible components, such as images and information. We conclude that since the latter half of the Late Holocene a macroregional system of integration based on symbolic complementarity included the Lower Paraná, the Central Hills, and the Santiagueña Plains. Objects and representations were instrumental in articulating a level of social integration in central-eastern Argentina and neighboring regions. We cannot fully understand the Indigenous societies of these regions without reference to the other peoples with whom they interacted through processes of trade and exchange. [ABSTRACT FROM AUTHOR]

Exploratory examinations were performed in sediments of archaeological levels from Cerro Casa de Piedra, cave 7 (CCP7). The aim of the present study was to identify parasitic remains present in the floor where human occupation has been reported. Parasite remains of Eimeria macusaniensis, molineids and two capillariids nematodes were identified. A single oocyst of Eimeria ivitaensis was found, resulting in the first report from Patagonia. Parasites found in this work were previously reported in camelid coprolites. Parasitological findings showed camelids presence into the cave and a high contamination of domestic area. These findings reinforce the hypothesis about the role of caves in parasites circulation among mammals community of Patagonia. [ABSTRACT FROM AUTHOR]

The aim of this research was to compare Projection Microscope (PMic) and Computerized Projection Microscope (CPMic) with Optical Fiber Diameter Analyzer (OFDA100), for the determination of the medullation in alpaca fibers expressed in percentage (MED). Fiber samples were taken from Pacomarca Scientific Station. Three experiments were carried out. At experiment 1, the MED was determined in 36 Huacaya alpaca males using PMic and OFDA100. At experiment 2, the MED was determined in 200 alpacas using CPMic and OFDA100 in Arequipa; and at experiment 3 carried out at Huancavelica, the MED was measured in 105 fiber samples with CPMic and OFDA100. OFDA medullation mean was very low in the three experiments (between 9.81±0.61 and 18.30±1.68%), compared with the total medullation obtained by the PMic (67.43±1.74%) and CPMic (between 28.71±1.37 and 41.14±2.00%). The continuous medullation + strongly medullated fibers reported by CPMic was even greater than OFDA medullation. These results indicate that the OFDA100 procedure provides very low and different reports of MED than PMic and CPMic. Although the OFDA100 was a system for rapid evaluation of wool MED, it would not be recommended in alpaca fibers. [ABSTRACT FROM AUTHOR]

Nanobodies (nAbs) are recombinant antigen-binding variable domain fragments obtained from heavy-chain-only immunoglobulins. Among mammals, these are unique to camelids (camels, llamas, alpacas, etc.). Nanobodies are of great use in biomedical research due to their efficient folding and stability under a variety of conditions, as well as their small size. The latter characteristic is particularly important for nAbs used as immunolabeling reagents, since this can improve penetration of cell and tissue samples compared to conventional antibodies, and also reduce the gap distance between signal and target, thereby improving imaging resolution. In addition, their recombinant nature allows for unambiguous definition and permanent archiving in the form of DNA sequence, enhanced distribution in the form of sequences or plasmids, and easy and inexpensive production using well-established bacterial expression systems, such as the IPTG induction method described here. This article will review the basic workflow and process for developing, screening, and validating novel nAbs against neuronal target proteins. The protocols described make use of the most common nAb development method, wherein an immune repertoire from an immunized llama is screened via phage display technology. Selected nAbs can then be taken through validation assays for use as immunolabels or as intrabodies in neurons. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Total RNA isolation from camelid leukocytes Basic Protocol 2: First-strand cDNA synthesis; VH H and VH repertoire PCR Basic Protocol 3: Preparation of the phage display library Basic Protocol 4: Panning of the phage display library Basic Protocol 5: Small-scale nAb expression Basic Protocol 6: Sequence analysis of selected nAb clones Basic Protocol 7: Nanobody validation as immunolabels Basic Protocol 8: Generation of nAb-pEGFP mammalian expression constructs Basic Protocol 9: Nanobody validation as intrabodies Support Protocol 1: ELISA for llama serum testing, phage titer, and screening of selected clones Support Protocol 2: Amplification of helper phage stock Support Protocol 3: nAb expression in amber suppressor E. coli bacterial strains.

The Argentinian Ministry of Environment has approved the translocation of 45 guanacos from Southern Patagonia to the Pampas region, a distance of 1500 km, as the initial phase toward future translocations into a National Park located in the Chaco region, another 1600 km further North. This decision raises concerns about the technical and ethical aspects of the translocation. Firstly, there is a lack of proper evaluation and scientific evidence to support the need, opportunity, and feasibility of this translocation. The guanaco population is currently over one million and is increasing, and genetic differences exist among local populations. The translocation could produce anthropogenic‐driven admixed populations, leading to genetic swamping and disrupting evolutionary processes. Second, there are ethical conflicts around managing wild species populations that prioritize private objectives and disregard local, publicly funded science. Rewilding projects require a deep understanding of interacting ecosystem processes, and of the socio‐economic context. This management decision violates guiding principles for rewilding and should have followed proper scientific evaluation and transparent local consultation. [ABSTRACT FROM AUTHOR]

Middle East respiratory syndrome coronavirus (MERS-CoV) infection can cause fatal pulmonary inflammatory disease in humans. Contrarily, camelids and bats are the main reservoir hosts, tolerant for MERS-CoV replication without suffering clinical disease. Here, we isolated cervical lymph node (LN) cells from MERS-CoV convalescent llamas and pulsed them with two different viral strains (clades B and C). Viral replication was not supported in LN, but a cellular immune response was mounted. Reminiscent Th1 responses (IFN-g, IL-2, IL-12) were elicited upon MERS-CoV sensing, accompanied by a marked and transient peak of antiviral responses (type I IFNs, IFN-l3, ISGs, PRRs and TFs). Importantly, expression of inflammatory cytokines (TNF-a, IL-1b, IL-6, IL-8) or inflammasome components (NLRP3, CASP1, PYCARD) was dampened. The role of IFN-l3 to counterbalance inflammatory processes and bridge innate and adaptive immune responses in camelid species is discussed. Our findings shed light into key mechanisms on how reservoir species control MERS-CoV in the absence of clinical disease. [ABSTRACT FROM AUTHOR]

Los Viscos, a multicomponent rockshelter in the high-altitude valley of El Bolsón, South-Central Andes, was occupied intermittently over the last 1200 years. One brief occupation dates to the early Hispanic-Indigenous contact period (ca. 1450–1630 cal CE), when European fauna were present but Hispanic political control was unestablished. Zooarchaeological analyses from this occupation are presented (NSP = 233; NISP = 83). Camelids were primarily exploited for meat and few other taxa were consumed, implying continuity with previous late pre-Hispanic occupations. Discontinuities include an apparent lack of camelid secondary product and dried meat exploitation. This is one of few studies documenting early Indigenous-European interactions in the area. [ABSTRACT FROM AUTHOR]

Simple Summary: This research employs fourteen and twelve microsatellite markers for two Huacaya alpaca populations from Southern Peru to estimate the genetic diversity and population structure. Our findings show that these two populations (Quimsachata and Ajoyani) were not structured. We also found that both populations have a large amount of diversity, which is a good indicator for conservation measures. These findings provide useful indicators regarding conservation programs created for this species to ensure their sustainable use. The alpaca population mostly consists of the Huacaya phenotype and is widely distributed in Southern Peru. This study aimed to estimate the genetic diversity and population structure of two Huacaya alpaca populations (Ajoyani and Quimsachata) using fourteen and twelve microsatellite markers for each population, respectively. A total of 168 alpaca biological samples were outsourced to Peruvian laboratories for DNA extraction and genotyping. For genetic diversity, observed heterozygosity (Ho), expected heterozygosity (He), polymorphism information content (PIC), and fixation indices values were estimated. An admixture analysis was performed for the population structure analysis. Different programs were used for these estimations. In total, 133 (Ajoyani) and 129 (Quimsachata) alleles were found, with a range of 4 to 17 by locus. The mean HO, HE, and PIC per marker for Ajoyani were 0.764 ± 0.112, 0.771 ± 0.1, and 0.736; for Quimsachata, they were 0.783 ± 0.087, 0.773 ± 0.095, and 0.738, respectively. The population structure showed no structure with K = 2. This study provides useful indicators for the creation of appropriate alpaca conservation programs. [ABSTRACT FROM AUTHOR]

Lysosomal storage diseases are inherited and acquired disorders characterized by dysfunctional lysosomes. Intracytoplasmic accumulation of undegraded substrates leads to impaired cellular function and death. Several plant species are toxic to livestock because of the presence of indolizidine alkaloids, including swainsonine, which cause a storage disease. Swainsonine-induced nervous disease (i.e., locoism) of sheep and cattle is well recognized in several parts of the world, particularly in the western United States and in parts of Australia. Spontaneous intoxication by Astragalus garbancillo var. garbancillo was suspected in a group of 70 llamas (Lama glama) in Jujuy Province, northwestern Argentina. The animals grazed an area dominated by stands of A. garbancillo var. garbancillo. Clinical signs were staggering, ataxia, hypermetria, and progressive weight loss. The clinical course in individual animals was ~50 d. The main microscopic changes were Purkinje cell degeneration, necrosis, and loss, associated with intracytoplasmic vacuolation, meganeurite formation, and Wallerian degeneration. Specific positive labeling for ubiquitin was observed in axonal spheroids. Composite leaf and stem samples of A. garbancillo var. garbancillo analyzed by high-performance liquid chromatography contained 0.03% swainsonine. Based on the microscopic lesions, clinical history, and plant analysis, a diagnosis was made of storage disease caused by consumption of swainsonine-containing A. garbancillo var. garbancillo.

Ulcers of the oral cavity, esophagus, and gastric compartments of South American camelids are uncommon. Multifocal-to-coalescing ulcers were identified in the oral cavity, esophagus, and/or gastric compartments of 5 alpacas submitted for postmortem examination. Fusobacterium necrophorum was isolated from the lesions in all alpacas, in combination with other aerobic and anaerobic bacteria. In 4 of these cases, F. necrophorum-associated lesions were considered secondary to neoplasia or other chronic debilitating conditions; in 1 case, the alimentary ulcers were considered the most significant autopsy finding. It is not known if this agent acted as a primary or opportunistic agent in mucosal membranes previously damaged by a traumatic event, chemical insult, immunodeficiency, or any other debilitating condition of the host.

Tetrabromobisphenol A (TBBPA) is the largest brominated flame retardant which can be released to environment and cause long-term hazard. In this work, we developed a rapid and highly sensitive fluorescence enzyme-linked immunosorbent assay (FELISA) for monitoring of TBBPA in soil samples. TBBPA specific nanobody derived from camelid was fused with alkaline phosphatase to obtain the bi-functional fusion protein, which enable the specific binding of TBBPA and the generation of detection signal simultaneously. The assay showed an IC50 of 0.23 ng g-1, limit detection of 0.05 ng g-1 and linear range from 0.1 to 0.55 ng g-1 for TBBPA in soil samples. Due to the high resistance to organic solvents of the fusion protein, a simple pre-treatment by using 40% dimethyl sulfoxide (DMSO) as extract solvent can eliminate matrix effect and obtain good recoveries (ranging from 93.4% to 112.4%) for spiked soil samples. Good relationship between the results of the proposed FELISA and that of liquid chromatography tandem mass spectrometry (LC-MS/MS) was obtained, which indicated it could be a powerful analytical tool for determination of TBBPA to monitor human and environmental exposure.

Coronaviruses are enveloped RNA viruses capable of causing respiratory, enteric, or systemic diseases in a variety of mammalian hosts that vary in clinical severity from subclinical to fatal. The host range and tissue tropism are largely determined by the coronaviral spike protein, which initiates cellular infection by promoting fusion of the viral and host cell membranes. Companion animal coronaviruses responsible for causing enteric infection include feline enteric coronavirus, ferret enteric coronavirus, canine enteric coronavirus, equine coronavirus, and alpaca enteric coronavirus, while canine respiratory coronavirus and alpaca respiratory coronavirus result in respiratory infection. Ferret systemic coronavirus and feline infectious peritonitis virus, a mutated feline enteric coronavirus, can lead to lethal immuno-inflammatory systemic disease. Recent human viral pandemics, including severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and most recently, COVID-19, all thought to originate from bat coronaviruses, demonstrate the zoonotic potential of coronaviruses and their potential to have devastating impacts. A better understanding of the coronaviruses of companion animals, their capacity for cross-species transmission, and the sharing of genetic information may facilitate improved prevention and control strategies for future emerging zoonotic coronaviruses. This article reviews the clinical, epidemiologic, virologic, and pathologic characteristics of nine important coronaviruses of companion animals.

Botulinum neurotoxin (BoNT) serotype E is one of three serotypes that cause the preponderance of human botulism cases and is a Tier 1 Select Agent. BoNT/E is unusual among BoNT serotypes for its rapid onset and short duration of intoxication. Here we report two large panels of unique, unrelated camelid single-domain antibodies (VHHs) that were selected for their ability to bind to BoNT/E holotoxin and/or to the BoNT/E light chain protease domain (LC/E). The 19 VHHs which bind to BoNT/E were characterized for their subunit specificity and 8 VHHs displayed the ability to neutralize BoNT/E intoxication of neurons. Heterodimer antitoxins consisting of two BoNT/E-neutralizing VHHs, including one heterodimer designed using structural information for simultaneous binding, were shown to protect mice against co-administered toxin challenges of up to 500 MIPLD50. The 22 unique VHHs which bind to LC/E were characterized for their binding properties and 9 displayed the ability to inhibit LC/E protease activity. Surprisingly, VHHs selected on plastic-coated LC/E were virtually unable to recognize soluble or captured LC/E while VHHs selected on captured LC/E were poorly able to recognize LC/E coated to a plastic surface. This panel of anti-LC/E VHHs offer insight into BoNT/E function, and some may have value as components of therapeutic antidotes that reverse paralysis following BoNT/E exposures.

Abstract Background Neospora caninum has been documented to infect most domestic wildlife but is known to primarily infect dogs and cattle and is considered an important cause of abortion in camels. Objective The aim of this study was to estimate the molecular detection of Neospora caninum in tissues of naturally infected camelids. Methods Brain, tongue (bottom and tip) and masseter muscles from 35 slaughtered camelids from Tataouine and Médenine regions were collected (n = 140 samples). PCR was used to amplify and detect N. caninum DNA in tissues samples followed by sequencing of some PCR products. A phylogenetic tree was then constructed to compare the partial sequences of the ITS1 gene with GenBank sequences. Histopathology examination was used to detect Neospora spp. cysts, but no lesions were observed. Results The overall molecular detection of N. caninum in camelids was 34.3% (12/35). The highest molecular detection of N. caninum was recorded in animals of more than 3 years old (6/9) and in animals aged between 1 and 3 years old (4/12). Whilst, the lowest molecular detection (2/14) was observed in animals 1 year or younger (p = 0.035). There were no significant differences in molecular detection of N. caninum according to both locality and gender (p > 0.05). Similarly, there was no difference of prevalence between different anatomical locations. Comparison of the partial sequences of the ITS1 gene revealed 100–95.5% similarity among our N. caninum amplicon (MW551566) and those deposited in GenBank. Conclusion These results highlight the presence of a risk infection by N. caninum in camels. For preventing N. caninum infection further studies are needed to improve our knowledge about the epidemiology of neosporosis in North Africa.

Pneumonic pathologies are clinically important in alpaca breeding; however, there is little information about pneumonic types and bacterial causes. The objective is to characterize pneumonias and bacteria causing pneumonias in neonates of dead alpacas in high Andean communities of Huancavelica, Peru. We sampled 365 dead alpaca pups under 45 days of age, from 10 communities, 216 of them were taken tracheal swabs for microbiological studies with peptone buffer because they were cases of pneumonia. Macroscopic identification of pneumonias was done by photodocumentation test. Pasteurella multocida, Mannheimia haemolytica were grown on Colombia agar enriched with alpaca blood; Streptococcus pneumoniae on Brain Heart Infusion agar supplemented with alpaca blood and identified by morphological and microscopic characterization, biochemical reactions and optokine. It was found 59.8% of mortality due to pneumonia and 40.2% by other causes, characterizing pneumonia by inflammation 55.1%, 44.9% by lesion and subtypes: Exudative 9.5%, Suppurative 3.8%, Proliferative 42.3%, Lobar 17.8%, Interstitial 26.6%, isolating strains Streptococcus pneumoniae 43.7%, Mannheimia haemolytica 14.9%, Pasteurella multocida 20.9%, predominant associates Streptococcus pneumoniae-Pasteurella multocida 10.7%. High frequency of types and subtypes of pneumonia associated to Gram (+) bacteria were observed as causal of pneumonia in alpaca pups, with predominance in three high Andean communities of Huancavelica, Peru. [ABSTRACT FROM AUTHOR]

Among the mammals domesticated by humans for their needs, the dromedary, which is a versatile animal, is used for the production of milk, meat, wool and skin, as well as for sports, tourism and transport. However, knowledge about the breeding and feeding of this animal is limited. The objective of this work is to synthesize previous works on the breeding and feeding of camels in Algeria. The results show that the main farming systems are transhumant, sedentary and nomadic. In addition, the diet of the dromedary is based on different types of Saharan routes and constitutes the main element upon which an extensive camel breeding system is based. Thus, for a better valorization of this species, further studies on the diet and breeding methods of camels are recommended. [ABSTRACT FROM AUTHOR]

This article examines the rise of native, segmentary lordships in the highlands of north-central Peru. It reports on new excavations and mapping at the seat of a prehispanic polity, Pashash (Recuay culture), a large hilltop center that developed after the collapse of Chavín civilization. Fieldwork revealed monumental constructions and two special activity contexts radiocarbon-dated to ca. a.d. 200–400: an offering area in a large palatial compound and a room-complex with chambers closed off and sealed with feasting refuse. Multiple lines of evidence help reconstruct a regional picture for the establishment of wealthy local elites. Cultural innovations explicitly link new leaders to roles in defense and warfare, economic production, and early burial cult within a high-status compound. The current data underscore a major break from earlier systems of authority and elite material culture, comprising an organizational pattern that was a precursor to the ethnic polities that predominated in later Andean prehistory. [ABSTRACT FROM AUTHOR]

Hemoparasites like Trypanosomes and Theileria impose drastic effects on normal functioning of vital organs with substantial changes in blood profile. Therefore, this study was designed to envisage such alterations in hemato-biochemical indices of camels naturally infected with Trypanosoma evansi (Tr. evansi) and Theileria annulata (Th. annulata). Blood samples (400) were collected from camels in Punjab, Pakistan and processed for Tr. evansi and Th. annulata by parasitological and molecular assays such as PCR (Polymerase chain reaction). The PCR positive samples for each parasites were evaluated for changes in hemato-biochemical parameters by performing hematology and serum biochemistry. The data obtained was analyzed in R statistical language (R version 4.1.3) using T-test and Mann Whitney Wilcox test at (P = 0.05). Results revealed the presence of Tr. evansi (8.25%) and Th. annulata (12%) by microscopic examination of Giemsa/Field stained blood smears while (14.8%) and (13.5%) prevalence was found respectively, by PCR using specific primers. The effects of Trypanosomiasis and Theileriosis on (Mean ± SE) values of several hematological parameters like, RBCs count, Hb conc., HCT, MCV, MCH, MCHC were significantly (P = 0.05) increased while WBCs count, lymphocytes, PLT and PCT were decreased compared with control. Likewise, values (Mean ± SE) of sero-biochemical parameters including glucose, iron, ALT, AST and total bilirubin had significant difference (P = 0.05), while creatinine, urea, ALP and BUN exhibited non-significant variations (P > 0.05) among the control and infected camels. The study inferenced the significant alterations in hemato-biochemical parameters of Tr. evansi and Th. annulata infected camels with the provision of comparable data for future studies. [ABSTRACT FROM AUTHOR]

Camelids have many unique reproductive features that considerably differ from those of other domestic species. Females are induced ovulators with subsequent development of a corpus luteum (CL) with a short lifespan. Plasma progesterone concentration starts to increase on day 4, peaks on day 8–9 and, in non‐pregnant animals, basal concentration is reached around day 10–11 post‐induction of ovulation. Luteolytic pulses of prostaglandin F2α (PGF2α) are firstly detected on day 7 or 8 (approximately on day 5–6 after ovulation), with maximal luteolytic peaks observed between days 9 and 11 post‐mating, in coincidence with a high endometrial expression of cyclooxygenase 2, a limiting enzyme in prostaglandins synthesis. Unlike other species, oxytocin seems not to be involved in the luteolytic process in these species. The CL is the main source of progesterone secretion, and its function is required to support pregnancy. Despite constant research efforts, aspects of reproduction and maternal recognition of pregnancy in camelids remain not fully understood. A transient decrease and subsequent recovery in plasma progesterone concentration are observed after day 9 post‐mating in pregnant animals in association with a pulsatile release of PGF2α and a transitory decrease in CL vascularization. Thus, embryo recognition should occur between days 8 and 12 post‐mating. In camels, conceptus tissues exhibit aromatizing activity with the capacity to synthesize large amounts of oestradiol. Similarly, llama blastocysts secrete oestradiol‐17β during the preimplantation stage, with a higher production during the elongation period. An increase in the endometrial expression of oestrogen receptor α is also observed on day 12 post‐mating. All these evidences suggest that oestrogen could be the signal released by the embryo at the time of its recognition in camelids. Besides, nearly 98% of pregnancies are carried out in the left horn. A decrease in the endometrial expression of mucin 1 and 16 genes has been reported, suggesting that these changes are crucial for successful embryo implantation; however, no differences have been observed between horns. Thus, maternal recognition of pregnancy in camelids is a particularly complex process that must occur in a concise time to allow the rescue of the CL and embryo survival. [ABSTRACT FROM AUTHOR]

Middle East respiratory syndrome coronavirus (MERS-CoV) infection can cause fatal pulmonary inflammatory disease in humans. Contrarily, camelids and bats are the main reservoir hosts, tolerant for MERS-CoV replication without suffering clinical disease. Here, we isolated cervical lymph node (LN) cells from MERS-CoV convalescent llamas and pulsed them with two different viral strains (clades B and C). Viral replication was not supported in LN, but a cellular immune response was mounted. Reminiscent Th1 responses (IFN-γ, IL-2, IL-12) were elicited upon MERS-CoV sensing, accompanied by a marked and transient peak of antiviral responses (type I IFNs, IFN-λ3, ISGs, PRRs and TFs). Importantly, expression of inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8) or inflammasome components (NLRP3, CASP1, PYCARD) was dampened. The role of IFN-λ3 to counterbalance inflammatory processes and bridge innate and adaptive immune responses in camelid species is discussed. Our findings shed light into key mechanisms on how reservoir species control MERS-CoV in the absence of clinical disease.

The actions of the beta-nerve growth factor (β-NGF) on the neuroendocrine and reproductive system have challenged classical views on the control of reproductive function. After endometrial absorption, β-NGF triggers ovulation and promotes the development of functional corpora lutea in camelids. In this article, we review evidence showing that, in camelids, β-NGF exerts its actions by acting in both the hypothalamus and the ovary. In the hypothalamus, β-NGF may induce gonadotropin-releasing hormone (GnRH) release by interacting with neurons or glial cells expressing receptors for β-NGF. The LH surge occurs under the influence of ovarian estradiol and requires the release of GnRH into the portal vessels to reach the pituitary gland. In the ovary, β-NGF may be promoting the differentiation of follicular to luteal cells by modifying the steroidogenic profile of ovarian follicular cells in both camelids and ruminants. Although the mechanisms for these actions are largely undetermined, we aim to offer an update on the current understanding of the effects of β-NGF controlling reproductive function in camelids and ruminants.

Medullated fibres, due to their higher resistance to bending and pressure, constitute a problem for the textile industry. Thus, having practical instruments to identify them is essential. Therefore, the aim of this research was to develop and validate a novel, swift, automatic system (referred to as S-Fiber Med) for medullation and diameter assessment of animal fibres based on artificial intelligence. The medullation of 88 samples of alpaca, llama and mohair fibres (41, 43 and 4, respectively) was evaluated. Additionally, 269 samples of alpacas were considered for average fibre diameter (AFD) and the results were compared with the Portable Fiber Tester (PFT) and Optical Fibre Diameter Analyser (OFDA) methods (72 and 197 samples, respectively). The preparation of each sample to be analysed followed the procedure described in IWTO-8-2011. Version 5 of “You Only Look Once” and DenseNet models were used to recognise the type of medullation and diameter of the fibres, respectively. Within each image (n = 661 for alpaca), all fibres were labelled (as Non-Medullated, Fragmented Medulla, Uncontinuous Medulla, Continuous Medulla and Strongly Medullated) using the LabelImg tool. Data augmentation technique was applied to obtain 3 966 images. Such data set was divided into 3 576 and 390 images for training and test data, respectively. For mohair samples (n = 321), a similar process was carried out. The data to train the model used to infer the diameter contained 16 446 fibres labelled with his respective AFD. A complementary hardware composed of three subsystems (mechanical, electronic, and optical) was developed for evaluation purposes. T-test, Pearson and Concordance correlation, Bland-Altman plot and linear regression analyses were used to validate and compare the S-Fiber Med with other methods. Results indicate that there was no significant difference between medullation percentage obtained with the projection microscope and the S-Fiber Med. The Pearson and Concordance correlation analysis shows a strong, high and significant relationship (P-value 0.172), and they have a strong, high and significant relationship between them, given the high Pearson correlation value (r ≥ 0.96 with P-value

BackgroundThe variable domain of camelid heavy-chain antibodies (VHH) is increasingly being adapted to detect small molecules in various matrices. The insecticide carbaryl is widely used in agriculture while its residues have posed a threat to food safety and human health.ResultsVHHs specific for carbaryl were generated from an alpaca immunized with the hapten CBR1 coupled to keyhole limpet hemocyanin. An enzyme-linked immunosorbent assay (ELISA) based on the VHH C1 and the coating antigen CBR2-BSA was developed for the detection of carbaryl in cereals. This assay, using an optimized assay buffer (pH 6.5) containing 10% methanol and 0.8% NaCl, has a half-maximum signal inhibition concentration of 5.4 ng mL-1 and a limit of detection (LOD) of 0.3 ng mL-1 for carbaryl, and shows low cross reactivity (≤0.8%) with other tested carbamates. The LOD of carbaryl using the VHH-based ELISA was 36 ng g-1 in rice and maize and 72 ng g-1 in wheat. Recoveries of carbaryl in spiked rice, maize and wheat samples were in the range of 81-106%, 96-106% and 83-113%, respectively. Relative standard deviations of repeatability and intra-laboratory reproducibility were in the range of 0.8-9.2% and 2.9-9.7%, respectively.ConclusionThe VHH-based ELISA was highly effective in detecting carbaryl in cereal samples after simple sample extraction and dilution. © 2019 Society of Chemical Industry.

Polycystic liver is usually considered an incidental finding in human and veterinary medicine. Two unrelated adult llamas ( Lama glama) with a history of marked anorexia and weight loss were received for autopsy and diagnostic workup. The main gross change in the liver of both animals was multiple variably sized cysts randomly distributed throughout the parenchyma. Histologically, the cysts compressed the adjacent parenchyma and were lined by a single layer of cuboidal-to-columnar epithelium, surrounded by a fibrous collagen capsule. The lumen of the cysts contained finely granular-to-homogeneous basophilic material. The lining epithelium displayed strong immunoreactivity for pancytokeratin AE1/AE3 and cytokeratins 7, 8, 8/18, and 19, and was negative for vimentin, confirming the biliary epithelial origin of the cysts. No parasitic or infectious agents, or neoplastic changes, were detected. All other laboratory tests performed in both llamas were negative or non-diagnostic, suggesting that the congenital hepatic cysts described may have been at least partly responsible for clinical disease in both animals.