Predicting bushmeat biomass from species composition captured by camera traps: Implications for locally based wildlife monitoring

アフリカ熱帯雨林における野生動物資源量推定の有効な指標を発見 --地域住民主体の野生動物モニタリング法の基礎を確立--. 京都大学プレスリリース. 2022-08-26.Cameras candidly capture bushmeat mammals to avert crisis. 京都大学プレスリリース. 2022-08-30.1. Facing the bushmeat crisis, tropical forests require effective monitoring for sustainable wildlife management. To gain credibility with local people and conservation officials, the monitoring needs indicators that comply with local knowledge and predict the available faunal resources. 2. This study explores predictive indicators for bushmeat biomass --the total biomass of five main hunted mammals-- in a Cameroonian rainforest. We employed camera trapping and the Random Encounter and Staying Time (REST) model to estimate the spatial variation in each species' population density and bushmeat biomass at three sites. We then calculated six indicators from camera-trap capture rate estimates and assessed their predictive performance for the total wild meat amount. 3. Duikers generally increased with distance from the public road, but two red duiker species were more markedly affected by the distance than blue duikers. Spatial density patterns of brush-tailed porcupines and Emin's pouched rats differed between sites. Consequently, bushmeat biomass displayed exponential growth away from the road with varying degrees among the sites. 4. Of the six indicators, the R/B ratio (red-to-blue duiker ratio) and the D/R ratio (duiker-to-rodent ratio) exhibited positive linear-like correlations to bushmeat biomass at all sites. The correlation lines were moderately similar across sites in the R/B ratio but largely different in the D/R ratio, suggesting that the latter is unsuitable for sharing information between neighbouring communities. 5. Synthesis and applications. The two indicators based on captured animal composition may effectively predict the total biomass of the main target species for bushmeat hunting, given a reasonably large sample size. The R/B ratio (red duikers/blue duikers) is recommended as a first choice; the D/R ratio (duikers/rodents) can be a good alternative when information sharing is not essential. Because local hunters are aware of depletion-related changes in species composition of caught animals, these indices may be effectively incorporated into community-based wildlife monitoring.1. Face à la crise de la viande de brousse, les forêts tropicales nécessitent un système de suivi efficace pour une gestion durable de la faune. Pour gagner en crédibilité auprès des populations locales et des responsables de la conservation, le suivi a besoin d'indicateurs qui respectent les connaissances locales et prédisent les ressources fauniques disponibles. 2. Cette étude explore des indicateurs prédictifs de la biomasse de la viande de brousse --la biomasse totale de cinq principaux mammifères chassés-- dans une forêt tropicale camerounaise. Nous avons utilisé des caméra-piège et le modèle REST (Random Encounter and Staying Time) pour estimer la variation spatiale de la densité de chaque espèce et de la biomasse de viande de brousse sur trois sites. Nous avons ensuite calculé six indicateurs à partir des estimations du taux de capture par caméra-piège et évalué leur performance prédictive pour la quantité totale de viande sauvage. 3. Le nombre de céphalophes augmentaient généralement avec la distance de la route publique, mais deux espèces de céphalophes roux étaient plus fortement affectés par la distance que les céphalophes bleus. Les modèles de densité spatiale des porcs-épics et des rats géants d'Emin différaient selon les sites. Par conséquent, la biomasse de viande de brousse a affiché une croissance exponentielle en s'éloignant de la route, avec des degrés variables selon les sites. 4. Parmi les six indicateurs, le ratio R/B (le ratio des céphalophes rouges par rapport aux céphalophes bleus) et le ratio D/R (le ratio des céphalophes par rapport aux rongeurs) présentaient des corrélations linéaires avec la biomasse de viande de brousse sur tous les sites. Les lignes de corrélation étaient modérément similaires d'un site à l'autre pour le ratio R/B mais largement différentes pour le ratio D/R, ce qui suggère que ce dernier n'est pas approprié pour le partage d'informations entre communautés adjacentes. 5. Synthèse et applications. Les deux indicateurs basés sur la composition des animaux capturés peuvent prédire efficacement la biomasse totale des principales espèces cibles de la chasse à la viande de brousse, à condition de disposer d'une taille d'échantillon raisonnablement importante. Le ratio R/B (les céphalophes rouges/bleus) est recommandé comme premier choix; le ratio D/R (les céphalophes/les rongeurs) peut être une bonne alternative lorsque le partage des informations n'est pas essentiel. Comme les chasseurs locaux sont conscients des changements liés à l'épuisement dans la composition des espèces des animaux capturés, ces indicateurs peuvent être efficacement intégrés dans le suivi communautaire de la faune

Effect of Saxagliptin on Endothelial Function in Patients with Type 2 Diabetes : A Prospective Multicenter Study

The dipeptidyl peptidase-4 inhibitor saxagliptin is a widely used antihyperglycemic agent in patients with type 2 diabetes. The purpose of this study was to evaluate the effects of saxagliptin on endothelial function in patients with type 2 diabetes. This was a prospective, multicenter, interventional study. A total of 34 patients with type 2 diabetes were enrolled at four university hospitals in Japan. Treatment of patients was initially started with saxagliptin at a dose of 5 mg daily. Assessment of endothelial function assessed by flow-mediated vasodilation (FMD) and measurement of stromal cell-derived factor-1α (SDF-1α) were conducted at baseline and at 3 months after treatment with saxagliptin. A total of 31 patients with type 2 diabetes were included in the analysis. Saxagliptin significantly increased FMD from 3.1 ± 3.1% to 4.2 ± 2.4% (P = 0.032) and significantly decreased total cholesterol from 190 ± 24 mg/dL to 181 ± 25 mg/dL (P = 0.002), glucose from 160 ± 53 mg/dL to 133 ± 25 mg/dL (P < 0.001), HbA1c from 7.5 ± 0.6% to 7.0 ± 0.6% (P < 0.001), urine albumin-to-creatinine ratio from 63.8 ± 134.2 mg/g to 40.9 ± 83.0 mg/g (P = 0.043), and total SDF-1α from 2108 ± 243 pg/mL to 1284 ± 345 pg/mL (P < 0.001). These findings suggest that saxagliptin is effective for improving endothelial function

Modulation of Wnt5a Expression by Periodontopathic Bacteria

Wingless proteins, termed Wnt, are involved in embryonic development, blood cell differentiation, and tumorigenesis. In mammalian hematopoiesis, Wnt signaling is essential for stem-cell homeostasis and lymphocyte differentiation. Recent studies have suggested that these molecules are associated with cardiovascular diseases, rheumatoid arthritis, and osteoarthritis. Furthermore, Wnt5a signaling is essential for the general inflammatory response of human macrophages. Periodontitis is a chronic inflammatory disease caused by gram-negative periodontopathic bacteria and the resultant host immune response. Periodontitis is characterized by loss of tooth-supporting structures and alveolar bone resorption. There have been no previous reports on Wnt5a expression in periodontitis tissue, and only few study reported the molecular mechanisms of Wnt5a expression in LPS-stimulated monocytic cells. Using RT-PCR, we demonstrated that Wnt5a mRNA expression was up-regulated in chronic periodontitis tissue as compared to healthy control tissue. P. gingivalis LPS induced Wnt5a mRNA in the human monocytic cell line THP-1 with a peak at 4 hrs after stimulation. P. gingivalis LPS induced higher up-regulation of Wnt5a mRNA than E. coli LPS. The LPS receptors TLR2 and TLR4 were equally expressed on the surface of THP-1 cells. P. gingivalis LPS induced IκBα degradation and was able to increase the NF-κB binding activity to DNA. P. gingivalis LPS-induced Wnt5a expression was inhibited by NF-κB inhibitors, suggesting NF-κB involvement. Furthermore, IFN-γ synergistically enhanced the P. gingivalis LPS-induced production of Wnt5a. Pharmacological investigation and siRNA experiments showed that STAT1 was important for P. gingivalis LPS-induced Wnt5a expression. These results suggest that the modulation of Wnt5a expression by P. gingivalis may play an important role in the periodontal inflammatory process and serve a target for the development of new therapies

Id4, a New Candidate Gene for Senile Osteoporosis, Acts as a Molecular Switch Promoting Osteoblast Differentiation

Excessive accumulation of bone marrow adipocytes observed in senile osteoporosis or age-related osteopenia is caused by the unbalanced differentiation of MSCs into bone marrow adipocytes or osteoblasts. Several transcription factors are known to regulate the balance between adipocyte and osteoblast differentiation. However, the molecular mechanisms that regulate the balance between adipocyte and osteoblast differentiation in the bone marrow have yet to be elucidated. To identify candidate genes associated with senile osteoporosis, we performed genome-wide expression analyses of differentiating osteoblasts and adipocytes. Among transcription factors that were enriched in the early phase of differentiation, Id4 was identified as a key molecule affecting the differentiation of both cell types. Experiments using bone marrow-derived stromal cell line ST2 and Id4-deficient mice showed that lack of Id4 drastically reduces osteoblast differentiation and drives differentiation toward adipocytes. On the other hand knockdown of Id4 in adipogenic-induced ST2 cells increased the expression of Pparγ2, a master regulator of adipocyte differentiation. Similar results were observed in bone marrow cells of femur and tibia of Id4-deficient mice. However the effect of Id4 on Pparγ2 and adipocyte differentiation is unlikely to be of direct nature. The mechanism of Id4 promoting osteoblast differentiation is associated with the Id4-mediated release of Hes1 from Hes1-Hey2 complexes. Hes1 increases the stability and transcriptional activity of Runx2, a key molecule of osteoblast differentiation, which results in an enhanced osteoblast-specific gene expression. The new role of Id4 in promoting osteoblast differentiation renders it a target for preventing the onset of senile osteoporosis