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1.
Anim Biotelemetry ; 11(1): 13, 2023.
Article in English | MEDLINE | ID: mdl-38800509

ABSTRACT

Bio-telemetry from small tags attached to animals is one of the principal methods for studying the ecology and behaviour of wildlife. The field has constantly evolved over the last 80 years as technological improvement enabled a diversity of sensors to be integrated into the tags (e.g., GPS, accelerometers, etc.). However, retrieving data from tags on free-ranging animals remains a challenge since satellite and GSM networks are relatively expensive and or power hungry. Recently a new class of low-power communication networks have been developed and deployed worldwide to connect the internet of things (IoT). Here, we evaluated one of these, the Sigfox IoT network, for the potential as a real-time multi-sensor data retrieval and tag commanding system for studying fauna across a diversity of species and ecosystems. We tracked 312 individuals across 30 species (from 25 g bats to 3 t elephants) with seven different device concepts, resulting in more than 177,742 successful transmissions. We found a maximum line of sight communication distance of 280 km (on a flying cape vulture [Gyps coprotheres]), which sets a new documented record for animal-borne digital data transmission using terrestrial infrastructure. The average transmission success rate amounted to 68.3% (SD 22.1) on flying species and 54.1% (SD 27.4) on terrestrial species. In addition to GPS data, we also collected and transmitted data products from accelerometers, barometers, and thermometers. Further, we assessed the performance of Sigfox Atlas Native, a low-power method for positional estimates based on radio signal strengths and found a median accuracy of 12.89 km (MAD 5.17) on animals. We found that robust real-time communication (median message delay of 1.49 s), the extremely small size of the tags (starting at 1.28 g without GPS), and the low power demands (as low as 5.8 µAh per transmitted byte) unlock new possibilities for ecological data collection and global animal observation.

2.
Front Med (Lausanne) ; 9: 975122, 2022.
Article in English | MEDLINE | ID: mdl-36117963

ABSTRACT

Background: Sarcoidosis is a systemic inflammatory disease that is characterized by non-caseating granulomas. Besides the lung as classical site of involvement, extrapulmonary manifestations are common, for example cervical lymph nodes or the salivary glands. The aim of this investigation is the analysis of the long-term course of glandular symptoms with a focus on persisting sicca symptoms. Materials and methods: All patients with the diagnosis of sarcoidosis over a period of 20 years in the departments of otorhinolaryngology, nephrology and pneumology were identified. In addition to clinical examinations and functional evaluation of the salivary glands, a sonographic examination of the salivary glands was carried out. Results: A total of 76 patients were included in the study (age 35.1 ± 21.6 years). At baseline, 32 out of 76 patients were suffering from xerostomia, 36 from dry eyes. While other salivary gland symptoms, such as gland enlargement, pain or facial nerve impairment, dissolved during the further course of the disease, xerostomia was still present in 29 and dry eyes in 35 out of 76 patients at the time of follow-up (which took place on average after 88.2 months). Conclusion: Sicca symptoms persist in patients with the diagnosis of sarcoidosis, while other salivary gland symptoms completely dissolve during the further course of the disease. This development appears to be independent of the type of therapy and should be considered during the follow-up of these patients, since sicca symptoms can cause further ocular, oral and dental damage.

3.
J Clin Med ; 11(9)2022 Apr 20.
Article in English | MEDLINE | ID: mdl-35566418

ABSTRACT

BACKGROUND: Sarcoidosis is a systemic inflammatory disease characterized by non-caseating granulomas. In addition to the lungs as classical site of affection, extrapulmonary manifestations are common, for example in the cervical lymph nodes or the salivary glands. The aim of this investigation is the analysis of the long-term course of glandular symptoms and the sonographic evaluation of long-term salivary gland changes. MATERIAL AND METHODS: All patients with a diagnosis of sarcoidosis over a period of 20 years in the departments of otorhinolaryngology, rheumatology, and pneumology were identified. In addition to clinical examinations and functional evaluation of the salivary glands, a sonographic examination of the salivary glands was carried out. The changes in the area of the salivary glands were assessed using B-mode sonography and different elastographic methods with appropriate scoring systems. RESULTS: A total of 76 patients were included in the study (age 35.1 ± 21.6 years). Overall, 17 patients presented with salivary gland manifestation at the time of the initial diagnosis. Of these patients, 15 received steroid therapy, 6 were also treated with another drug, and 2 patients were not treated with drugs. The time span between initial diagnosis and follow-up was 88.2 months (±83.0). At the time of the initial diagnosis, 17/17 complained of swelling of the salivary glands, 9/17 of xerostomia, and 8/17 of pain in the area of the salivary glands. At the time of follow-up, 5/17 reported swelling of the salivary glands, 6/17 reported xerostomia, and 1/17 reported pain in the salivary gland area. Sonography showed sonomorphological abnormalities of the salivary glands only in individual cases, with only mild alterations on average. CONCLUSION: In summary, it can be observed that patients with initial symptoms in the area of the salivary glands, such as swelling or pain, also suffer more frequently from dry mouth and eyes. In all patients, however, these symptoms regressed over time. A previous diagnosis of sarcoidosis with involvement of the salivary glands only leads to permanent abnormalities in the area of the salivary glands in individual cases.

4.
Biology (Basel) ; 11(2)2022 Jan 18.
Article in English | MEDLINE | ID: mdl-35205021

ABSTRACT

The preservation of rhinoceros semen is vital for captive breeding programs. While successful collection and cryopreservation of rhinoceros semen has been reported, the volume and quality of semen produced is often low due to the high viscosity associated with ejaculates collected via electroejaculation. Reducing semen viscosity would enable access to previously unusable spermatozoa from viscous fractions and could improve quality post-thaw. The enzyme papain successfully reduced the viscosity of camelid semen but has yet to be tested in wildlife species. This study assessed the influence of papain on the in vitro quality of rhinoceros spermatozoa during cryopreservation using advanced semen assessment. In experiment 1, the motility of spermatozoa from the viscous fraction of an ejaculate, either untreated or treated with papain and its inhibitor E-64 prior to cryopreservation, was assessed post-thaw. In experiment 2, spermatozoa from papain-treated viscous fractions were compared to spermatozoa frozen from untreated sperm-rich fractions pre-freeze, as well as after 0, 1.5 and 3 h of incubation post-thaw (37 °C). Papain significantly increased the quantity of spermatozoa collected from ejaculates, as well as the motility prior to freezing. Papain also improved the post-thaw motility, velocity, linearity and straightness of samples compared to sperm-rich samples, with no detriment to sperm viability, lipid membrane disorder, production of ROS or DNA integrity (p < 0.05). Results show the benefit of supplementing rhinoceros spermatozoa with papain prior to cryopreservation on sperm cryosurvival and demonstrates the potential of using papain to improve the success of cryopreservation protocols, not only for the rhinoceros, but also for other wildlife species.

5.
Theriogenology ; 156: 181-188, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-32755717

ABSTRACT

In captive rhinoceros stillbirth and perinatal death are recorded at a rate of 6-17% in the various species. At the same time there is a substantial lack of knowledge on rhinoceros parturition. Yet, predicting parameters for birth and progress of parturition are fundamental for the recognition of dystocia and perinatal problems. Therefore, we here intended to pay close attention to the Achilles heel of the 1.5-2.5 year reproduction cycle in rhinoceros, the parturition. For the prediction of parturition we recorded timelines for pre-birth udder development, genital swelling, milk production, behavioral unrest, and decrease of serum progesterone concentration and the gestational length in 19 white rhinoceros. First, second and third labour stage, foetal presentation and events in perinatal period were recorded to describe normal parturition and establish a guideline for better birth management in rhinoceros. Udder development and genital swelling were observed 3 and 2 weeks prior birth, respectively. Milk production was observed to start up to 3 weeks prior birth and increased significantly in the last week with most significant increase one day before parturition to 50.6 ± 45.4 mL (p < 0.006). Serum progesterone concentration started to decrease 7 days prior parturition and more significantly 48 h before parturition. While behavioral unrest and first stage labour was not observed reliably in all females the break of foetal waters and thus the start of second stage labour was unmistakably observed. Second stage labour, when foetal membranes had ruptured until the foetus was born, took 1:50 ± 0:20 h:min. Eighty-four percent of fetuses were born in anterior presentation (n = 16/19) and the final expulsion took <25 min suggesting that this is the normal presentation in white rhinoceros. In the less frequent posterior presentation final expulsion took up to 47 min. Overall, 95% of calves were born alive. Calves were standing and nursing in 0:55 ± 0:12 min and 3:32 ± 0:53 h:min, respectively. In 10.5% of births (n = 2/19) in anterior presentation perinatal complications occurred. Stillbirth occurred once (5.3% n = 1/19) when the foetus was born in posterior presentation. The recorded gestational length was 506 ± 2d. Delivering live offspring is of key importance to establish a new generation and secure long-term survival of a species. Various pre-birth changes, significant decrease of serum progesterone 48 h prior birth, different labour stages, foetal presentation and perinatal events described here add substantial knowledge on the understanding of normal rhinoceros parturition and may help diagnose dystocia and perinatal complications.


Subject(s)
Dystocia , Labor, Obstetric , Animals , Dystocia/veterinary , Female , Parturition , Perissodactyla , Pregnancy , Stillbirth/veterinary
6.
Tissue Eng Part A ; 26(15-16): 915-926, 2020 08.
Article in English | MEDLINE | ID: mdl-32070231

ABSTRACT

Adipose-derived mesenchymal stromal/stem cells (ASCs) represent a commonly used cell source for adipose tissue engineering. In this context, ASCs have routinely been cultured in conventional 2D culture and applied as single cell suspension for seeding onto scaffold materials or direct injection. However, this approach is associated with the loss of their intrinsic 3D microenvironment and leads to impaired regenerative capacity of the cells. Thus, the application of ASCs as self-assembled 3D spheroids with cells residing in their own matrix is an attractive alternative. However, characterization of the structural features and differentiation capacity of the spheroids is necessary to effectively apply them as building blocks in adipose tissue engineering. In this study, we focus on extracellular matrix (ECM) development in ASC spheroids, as well as adipogenic differentiation in comparison to conventional 2D culture using different induction protocols. Reproducible assembly of ASCs into spheroids was achieved within 24 h using the liquid overlay technique. Undifferentiated spheroids displayed a stromal ECM pattern, with fibronectin, collagen V, and VI as the main components. In the course of adipogenesis, a dynamic shift in the ECM composition toward an adipogenic phenotype was observed, associated with enhanced expression of laminin, collagen I, IV, V, and VI, similar to native fat. Furthermore, adipogenic differentiation was enhanced in spheroids as compared with 2D cultured cells, with the spheroids needing a distinctly shorter adipogenic stimulus to sustain adipogenesis, which was demonstrated based on analysis of triglyceride content and adipogenic marker gene expression. In summary, culturing ASCs as spheroids can enhance their adipogenic capacity and generate adipose-like microtissues, which may be a promising cell delivery strategy for adipose tissue engineering approaches. Impact statement Adipose-derived mesenchymal stromal/stem cells (ASCs) as a widely used cell source for adipose tissue engineering have been shown to be limited in their regenerative capacity when applied as single cells. As an alternative approach, the delivery as spheroids, consisting of cells in a 3D context, may be favorable. However, insights into extracellular matrix (ECM) development and efficient adipogenic differentiation are required for their effective application. In this study, we show that differentiated ASC spheroids develop an ECM, resembling native adipose tissue. Furthermore, the ASC spheroids exhibited a superior differentiation capacity as compared with conventional 2D culture, and required only a short adipogenic induction stimulus. Our results identify ASC-derived spheroids as an attractive cell delivery method for adipose tissue engineering approaches.


Subject(s)
Adipogenesis , Adipose Tissue , Extracellular Matrix , Mesenchymal Stem Cells , Cell Differentiation , Cells, Cultured , Humans , Tissue Engineering
7.
Adv Healthc Mater ; 8(7): e1801326, 2019 04.
Article in English | MEDLINE | ID: mdl-30835969

ABSTRACT

Melt electrowriting (MEW) is an additive manufacturing technology that is recently used to fabricate voluminous scaffolds for biomedical applications. In this study, MEW is adapted for the seeding of multicellular spheroids, which permits the easy handling as a single sheet-like tissue-scaffold construct. Spheroids are made from adipose-derived stromal cells (ASCs). Poly(ε-caprolactone) is processed via MEW into scaffolds with box-structured pores, readily tailorable to spheroid size, using 13-15 µm diameter fibers. Two 7-8 µm diameter "catching fibers" near the bottom of the scaffold are threaded through each pore (360 and 380 µm) to prevent loss of spheroids during seeding. Cell viability remains high during the two week culture period, while the differentiation of ASCs into the adipogenic lineage is induced. Subsequent sectioning and staining of the spheroid-scaffold construct can be readily performed and accumulated lipid droplets are observed, while upregulation of molecular markers associated with successful differentiation is demonstrated. Tailoring MEW scaffolds with pores allows the simultaneous seeding of high numbers of spheroids at a time into a construct that can be handled in culture and may be readily transferred to other sites for use as implants or tissue models.


Subject(s)
Tissue Engineering , Tissue Scaffolds/chemistry , Adipogenesis/drug effects , Adipose Tissue/cytology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Cell Differentiation/drug effects , Cell Survival/drug effects , Humans , Lipid Droplets/metabolism , Polyesters/chemistry , Porosity , Printing, Three-Dimensional , Sepharose/chemistry , Spheroids, Cellular/cytology , Spheroids, Cellular/metabolism , Stromal Cells/cytology , Stromal Cells/metabolism
8.
J Cell Physiol ; 233(4): 3315-3329, 2018 04.
Article in English | MEDLINE | ID: mdl-28888046

ABSTRACT

Adipose-derived stromal/stem cells (ASCs) represent a widely used cell source with multi-lineage differentiation capacity in approaches for tissue engineering and regenerative medicine. Despite the multitude of literature on their differentiation capacity, little is reported about the physiological properties contributing to and controlling the process of lineage differentiation. Direct intercellular communication between adjacent cells via gap junctions has been shown to modulate differentiation processes in other cell types, with connexin 43 (Cx43) being the most abundant isoform of the gap junction-forming connexins. Thus, in the present study we focused on the expression of Cx43 and gap junctional intercellular communication (GJIC) in human ASCs, and its significance for adipogenic differentiation of these cells. Cx43 expression in ASCs was demonstrated histologically and on the gene and protein expression level, and was shown to be greatly positively influenced by cell seeding density. Functionality of gap junctions was proven by dye transfer analysis in growth medium. Adipogenic differentiation of ASCs was shown to be also distinctly elevated at higher cell seeding densities. Inhibition of GJIC by 18α-glycyrrhetinic acid (AGA) significantly compromised adipogenic differentiation, as demonstrated by histology, triglyceride quantification, and adipogenic marker gene expression. Flow cytometry analysis showed a lower proportion of cells undergoing adipogenesis when GJIC was inhibited, further indicating the importance of GJIC in the differentiation process. Altogether, this study demonstrates the impact of direct cell-cell communication via gap junctions on the adipogenic differentiation process of ASCs, and may contribute to further integrate direct intercellular crosstalk in rationales for tissue engineering approaches.


Subject(s)
Adipogenesis , Adipose Tissue/cytology , Cell Communication , Gap Junctions/metabolism , Stem Cells/metabolism , Cell Count , Connexin 43/metabolism , Humans , Stromal Cells/metabolism
9.
J Genet Genomics ; 41(3): 107-15, 2014 Mar 20.
Article in English | MEDLINE | ID: mdl-24656231

ABSTRACT

The synaptonemal complex (SC) is an evolutionarily well-conserved structure that mediates chromosome synapsis during prophase of the first meiotic division. Although its structure is conserved, the characterized protein components in the current metazoan meiosis model systems (Drosophila melanogaster, Caenorhabditis elegans, and Mus musculus) show no sequence homology, challenging the question of a single evolutionary origin of the SC. However, our recent studies revealed the monophyletic origin of the mammalian SC protein components. Many of them being ancient in Metazoa and already present in the cnidarian Hydra. Remarkably, a comparison between different model systems disclosed a great similarity between the SC components of Hydra and mammals while the proteins of the ecdysozoan systems (D. melanogaster and C. elegans) differ significantly. In this review, we introduce the basal-branching metazoan species Hydra as a potential novel invertebrate model system for meiosis research and particularly for the investigation of SC evolution, function and assembly. Also, available methods for SC research in Hydra are summarized.


Subject(s)
Hydra/metabolism , Meiosis/physiology , Synaptonemal Complex/metabolism , Animals , Caenorhabditis elegans/metabolism , Cell Lineage , Drosophila melanogaster/metabolism , Evolution, Molecular , Hydra/cytology , Hydra/genetics , Models, Animal , Species Specificity , Vertebrates
10.
BMC Res Notes ; 7: 159, 2014 Mar 19.
Article in English | MEDLINE | ID: mdl-24642114

ABSTRACT

BACKGROUND: The human endogenous retrovirus K (HERV-K) has been acquired by the genome of human ancestors million years ago. It is the most complete of the HERVs with transcriptionally active gag, pol and env genes. Splice variants of env, which are rec, 1.5 kb transcript and Np9 have been suggested to be tumorigenic. Transcripts of HERV-K have been detected in a multitude of human cancers. However, no such reports are available concerning glioblastomas (GBM), the most common malignant brain tumor in adults. Patients have a limited prognosis of 14.6 months in median, despite standard treatment. Therefore, we elucidated whether HERV-K transcripts could be detected in these tumors and serve as new molecular target for treatment. FINDINGS: We analyzed human GBM cell lines, tissue samples from patients and primary cell cultures of different passages for HERV-K full length mRNA and env, rec and 1.5 kb transcripts. While the GBM cell lines U138, U251, U343 and GaMG displayed weak and U87 strong expression of the full length HERV-K, the splice products could not be detected, despite a weak expression of env mRNA in U87 cells. Very few tissue samples from patients showed weak expression of env mRNA, but none of the rec or 1.5 kb transcripts. Primary cells expressed the 1.5 kb transcript weakly in early passages, but lost HERV-K expression with extended culture time. CONCLUSIONS: These data suggest that HERV-K splice products do not play a role in human malignant gliomas and therefore, are not suitable as targets for new therapy regimen.


Subject(s)
Brain Neoplasms/genetics , Endogenous Retroviruses/genetics , Gene Expression Regulation, Neoplastic , Gene Expression Regulation, Viral , Glioblastoma/genetics , Adult , Aged , Brain Neoplasms/pathology , Brain Neoplasms/virology , Cell Line, Tumor , Glioblastoma/pathology , Glioblastoma/virology , Humans , Male , Middle Aged , RNA Splicing , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Time Factors , Tumor Cells, Cultured
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