Kisspeptin (Kp-10) inhibits in vitro osteogenic differentiation of multipotent mesenchymal stromal cells extracted from the bone marrow of adult rats

Kisspeptin (Kp-10) is a neuropeptide that binds to GPR54 receptors, exerting several functions mainly in the nervous and reproductive systems of the body. However, its effects and mechanisms of action on the skeletal system remain poorly understood. This study evaluated the effects of different concentrations of Kp-10 on in vitro osteogenic differentiation of multipotent mesenchymal stromal cells (MSCs) extracted from the bone marrow (BM) of adult Wistar rats. Two-month-old female rats were euthanized to extract BM from long bones to obtain MSCs. Four experimental groups were established in vitro: a control and Kp-10 at concentrations of 0.01, 0.05 and, 0.1 µg/mL. After induction of osteogenic differentiation, cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide (MTT) assay, alkaline phosphatase activity, collagen synthesis, percentage of area covered by MSCs/field and mineralized nodules/field, and immunocytochemistry of the GPR54 receptor tests. Furthermore, evaluation of gene transcripts for type I collagen, Runx-2, Bmp-2, bone sialoprotein, osteocalcin and osteopontin was performed using real-time RT-qPCR. It was observed that MSCs expressed GPR54 receptor to which Kp-10 binds during osteogenic differentiation, promoting a negative effect on osteogenic differentiation. This effect was observed at all the Kp-10 concentrations in a concentration-dependent manner, characterized by a decrease in the activity of alkaline phosphatase, collagen synthesis, mineralized nodules, and decreased expression of gene transcripts for type I collagen, osteocalcin, osteopontin, and Runx-2. Thus, Kp-10 inhibits in vitro osteogenic differentiation of MSCs extracted from the BM of adult Wistar rats.

Effect of the addition of different concentrations of Solanum glaucophyllum desf. extract on chondrocyte cultures from the growth cartilage of newborn rats

Solanum glaucophyllum Desf. Is a calcinogenic plant responsible for enzootic calcinosis that affects ruminants and causes alterations in bone and cartilaginous tissues, among others. It is believed that changes in cartilage tissue, with reduced bone growth, are due to hypercalcitoninism, caused by excess vitamin D. However, we hypothesized that S. glaucophyllum Desf. Can act directly on chondrocytes and therefore, chondrocyte cultures from the epiphysis of the long bones of newborn rats were used as a model to elucidate the direct effects of S. glaucophyllum Desf. On bone growth. Plant samples were collected from Cañuelas, Argentina. An aliquot of the plant extract was used to quantify vitamin D (1,25(OH)2D3). The effects of the three concentrations of the plant extract were tested in cultures of chondrocytes extracted from the epiphyses of the long bones of 32 three-day-old Wistar rats. A control group (without extract treatment), and three groups treated with different concentrations of plant extract were formed: group 1 (100 μL/L); group 2 (1 mL/L), and group 3 (5 mL/L), containing respectively 1 × 10^-9 M, 1 × 10^-8 M, and 5 × 10^-8 M of 1,25(OH)2D3. After 7, 14, and 21 days of culture, MTT assay for cell viability, alkaline phosphatase activity, and quantification of the percentage of areas with glycosaminoglycans (GAG) stained with periodic acid-Schiff (PAS) were performed. On day 7, all chondrocytes in group 3, that is, those with the highest concentration of plant extract, died. On days 14 and 21, groups 1 and 2 showed a significant reduction in chondrocyte viability compared to the control. At 7, 14, and 21 days, groups 1 and 2 showed significantly lower alkaline phosphatase activity than the control. On day 21, group 2 showed a significant reduction in areas with PAS + GAGs. There were no significant differences between the groups in the expression of gene transcripts for Sox9, Col2, ColX, and aggrecan. The S. glaucophyllum Desf. Extract directly affected growing rat chondrocytes by reducing viability, alkaline phosphatase activity, and GAG synthesis without altering the expression of gene transcripts for Sox9, Col2, ColX, and aggrecan, which may be one of the mechanisms by which there is a reduction in bone growth in animals intoxicated by the plant.

Differentiation of canine adipose mesenchymal stem cells into insulin-producing cells: comparison of different culture medium compositions

The aim of this study was to differentiate canine adipose-derived mesenchymal stem cells (ADMSCs) into insulin-producing cells by using culture media with different compositions to determine the most efficient media. Stem cells isolated from the fat tissues close to the bitch uterus were distributed into 6 groups: (1) Dulbecco's modified Eagle medium (DMEM)-high glucose (HG), β-mercaptoethanol, and nicotinamide; (2) DMEM-HG, β-mercaptoethanol, nicotinamide, and exendin-4; (3) DMEM-HG, β-mercaptoethanol, nicotinamide, exendin-4, B27, nonessential amino acids, and l-glutamine; (4) DMEM-HG, β-mercaptoethanol, and nicotinamide (for the initial 8-d period), and DMEM-HG, β-mercaptoethanol, nicotinamide, exendin-4, B27, nonessential amino acids, l-glutamine, and basic fibroblast growth factor (for the remaining 8-d period); (5) DMEM-HG and fetal bovine serum; and (6) DMEM-low glucose and fetal bovine serum (standard control group). Adipose-derived mesenchymal stem cells from groups 1 to 5 gradually became round in shape and gathered in clusters. These changes differed between the groups. In group 3, the cell clusters were apparently more in numbers and gathered as bigger aggregates. Dithizone staining showed that groups 3 and 4 were similar in terms of the mean area of each aggregate stained for insulin. However, only in group 4, the number of insulin aggregates and the total area of aggregates stained were significantly bigger than in the other groups. The mRNA expression of PDX1, BETA2, MafA, and Insulin were also confirmed in all the groups. We conclude that by manipulating the composition of the culture medium it is possible to induce canine ADMSCs into insulin-producing cells, and the 2-staged protocol that was used promoted the best differentiation.

Canine umbilical cord perivascular tissue: A source of stem cells for therapy and research

There are numerous sources of multipotent mesenchymal stromal cells (MSC) with therapeutic potential, and bone marrow is the main one. However, pain, lack of donors and comorbidities associated with harvesting stimulate the search for new sources of MSCs. The aim of this work is to obtain cells from umbilical cord (UC) perivascular tissue of dogs and characterize them as MSCs. For this, the UC was obtained from therapeutic cesarean sections and submitted to enzymatic digestion. The obtained cells were subjected to growth and proliferation tests, as well as the analysis of surface markers, differentiation test in three mesenchymal lineages and analysis of differentiation markers expression. From all the UC used in this study an adherent with fibroblastoid shape cell was obtained, with an initial number of 4.8 × 10⁵ of cells. The growth curves showed a lag phase from 0 to 24 h, followed by a phase of growth of 24 to 168 h, and then phase of cell decay. The doubling time was kept around 15 h until the sixth passage, from which there were signs of cellular senescence. The differentiation assays demonstrated the ability of cells to differentiate into osteoblasts, adipocytes and chondrocytes when subjected to the induction mediums. The study of surface markers was positive for adhesion markers and negative for hematopoietic markers. Thus, cells obtained from canine UC perivascular tissue by enzymatic digestion are multipotent MSC and the protocol developed ensures the perivascular origin of these cells.

Influência do jejum alimentar na mortalidade, perda de peso vivo, fraturas, hematomas, e contaminação de carcaças em abatedouro de frangos

O objetivo do trabalho foi avaliar a influência do jejum alimentar em diferentes etapas ante-mortem na ocorrência de mortes, perda de peso vivo, contaminação e condenação de carcaças por fraturas e hematomas de aves em abatedouro de frangos de Minas Gerais. Foram avaliados 1.072.491 frangos distribuídos em 312 lotes/caminhões. Foram determinados os períodos de retirada da ração até o início da apanha, da apanha, de transporte, de espera das aves no pátio do abatedouro até o momento do abate e de todo o jejum. O peso vivo das aves foi obtido em granjas e a mortalidade e perda de peso vivo foram determinadas assim que os animais chegaram ao abatedouro. Carcaças com fraturas, hematomas e contaminadas por fezes/bile foram quantificadas no abatedouro. O jejum durante a espera dos animais no pátio do abatedouro antes do abate influenciou (P<0,05) a contaminação das carcaças por fezes/bile e a perda de peso vivo dos frangos. O jejum durante o transporte influenciou (P<0,05) a mortalidade de frangos ao chegarem ao abatedouro. O jejum durante a retirada da ração até a apanha influenciou (P<0,05) a perda de peso vivo e a ocorrência de fraturas e hematomas nos frangos. Todo o período de jejum influenciou (P<0,05) a perda de peso vivo dos frangos. Portanto, a mortalidade, fraturas, hematomas, perda de peso vivo de frangos e a contaminação de carcaças estão diretamente relacionados com o jejum em diferentes etapas ante-mortem, o que pode causar prejuízos para a indústria avícola.

The genomics of mycobacteria

The species Mycobacterium bovis and Mycobacterium avium subspecies paratuberculosis are the causal agents, respectively, of tuberculosis and paratuberculosis in animals. Both mycobacteria, especially M. bovis, are also important to public health because they can infect humans. In recent years, this and the impact of tuberculosis and paratuberculosis on animal production have led to significant advances in knowledge about both pathogens and their host interactions. This article describes the contribution of genomics and functional genomics to studies of the evolution, virulence, epidemiology and diagnosis of both these pathogenic mycobacteria.

Epidemiology of bovine anaplasmosis in dairy herds from Costa Rica

Bovine anaplasmosis is endemic and occurs in almost all areas of livestock production of Costa Rica. The aim of this study was to determine the seroprevalence and risk factors of anaplasmosis in dairy farms of Costa Rica by the recombinant truncated MSP-5 (rMSP-5) enzyme-linked immunosorbent assay (ELISA). Serum samples were obtained from 733 cattle from 20 commercial dairy herds of Costa Rica. The overall seroprevalence was 37.2% and herd seroprevalence ranged from 20.0 to 72.0%. The age-specific seroprevalence was 49.3% in young and 33.4% in adult animals. The main risk factors associated with seroprevalence were season of occurrence of clinical cases (rainy season) (OR=22.8), presence of tabanids (OR=9.5) and stable flies (OR=6.2), stable flies control measures (OR=3.2), non-use of ear tattoos (OR=2.8), interval of veterinary visit (≤ 60 days) (OR=2.7), altitude of the farms (<800 masl) (OR=2.6) and age (<2 years) (OR=1.8). The results indicated that exposure of cattle to Anaplasma marginale is common in dairy herds of Costa Rica and endemic instability situation probably is due to inadequate vector control.

Molecular detection of Anaplasma platys in a naturally-infected cat in Brazil

Following the accidental finding of inclusion bodies similar to Anaplasma platys in a stained blood smear from a cat, DNA analysis of the 16S rRNA gene was performed and 100% identity was found with different strains of A. platys. These data confirm that cats are susceptible to parasitism by A. platys.

[Cutaneous larva migrans in children in a school of center-western Brazil]

This paper reports an outbreak of cutaneous larva migrans in children of a school located in Campo Grande, MS. Six out of the 16 students (37.5%) acquired this parasitic dermatitis in two playgrounds contaminated by cat feces, in which ancylostomid larvae were found. The serpiginous lesions and/or papules were located in the hands, feet, buttocks, thighs, vulva and scrotum. Control measures of this parasitosis are discussed.

Severe cat flea infestation of dairy calves in Brazil

An investigation was conducted into a severe flea infestation on dairy calves. Inspection of the dairy revealed a high infestation of Ctenocephalides felis felis on four calves and thousands of fleas in the stable where cows and calves were brought in for milking. A 3-month-old female calf was highly infested with fleas. The animal showed an evident lethargy, weight loss, as well as pale mucous membranes and dehydration. Hematological analysis revealed anemia, with 10% packed cell volume and a 1.72 x 10(6) microl(-1) erythrocyte count. Blood transfusions were performed and the flea infestation was controlled with 1% fipronil pour-on (1 ml/10 kg). The farmer was advised to treat the other calves with fipronil, remove the manure from the stable and spread 1% propoxur powder (100 g/m2) onto the floor of the stable.

Comparison between enzyme-linked immunosorbent assay, indirect fluorescent antibody and rapid conglutination tests in detecting antibodies against Babesia bovis

The performance of an enzyme-linked immunosorbent assay (ELISA), an indirect fluorescent antibody test (IFAT) and a rapid conglutination test (RCT) for the detection of antibodies against Babesia bovis, was evaluated with 462 cattle sera from Bahia State; Brazil. The results showed a concordance of 96.6% between the ELISA and IFAT, 90.5% between the ELISA and RCT, and 91.8% between the IFAT and RCT. Although the prevalence rates determined by ELISA (97.2%) and IFAT (96.8%) were higher than that indicated by the RCT (92.9%), performances of the three serological tests were very similar and characterized the region studied as enzootically stable to B. bovis.

[Transverse myelitis as initial symptom of disseminated non-Hodgkin lymphoma and HIV-associated vacuolar myelopathy: case report]

Non-Hodgkin lymphoma is frequently seen in AIDS patients usually affecting the central nervous system (CNS), especially the leptomeninges and the cerebral hemispheres. The epidural involvement is rarely described, ranging from 3.5% to 8.3% among the CNS sites. The authors present a case of disseminated non Hodgkin lymphoma associated to vacuolar myelopathy in a 27 years-old male patient with AIDS emphasizing the importance of this differential diagnosis in the myelopathies of AIDS.