Comparative Study of Human Hematopoietic Cell Engraftment into Balb/c and C57BL/6 Strain of Rag-2/Jak3 Double-Deficient Mice

Immunodeficient mice are becoming invaluable tools in human stem cell and tumor research. In this study, we generated Rag-2/Jak3 double-deficient (Rag-2−/−Jak3−/−) mice with a C57/BL6 and Balb/c genetic background and compared the human lymphohematopoietic cell engraftment rate. Human cord blood-derived CD34+ hematopoietic stem cells were successfully engrafted into Balb/c Rag-2−/−Jak3−/− mice; however, the engraftment rate was far lower in C57/BL6 Rag-2−/−Jak3−/− mice. Transplantation of human peripheral blood mononuclear cells resulted in the same tendency. Thus, a Balb/c background offers superior engraftment capacity than a C57/BL6 background and provides an attractive model for human hematopoietic cell engraftment

Sodium-coupled Monocarboxylate Transporters in Normal Tissues and in Cancer

SLC5A8 and SLC5A12 are sodium-coupled monocarboxylate transporters (SMCTs), the former being a high-affinity type and the latter a low-affinity type. Both transport a variety of monocarboxylates in a Na+-coupled manner. They are expressed in the gastrointestinal tract, kidney, thyroid, brain, and retina. SLC5A8 is localized to the apical membrane of epithelial cells lining the intestinal tract and proximal tubule. In the brain and retina, its expression is restricted to neurons and the retinal pigment epithelium. The physiologic functions of SLC5A8 include absorption of short-chain fatty acids in the colon and small intestine, reabsorption of lactate and pyruvate in the kidney, and cellular uptake of lactate and ketone bodies in neurons. It also transports the B-complex vitamin nicotinate. SLC5A12 is also localized to the apical membrane of epithelial cells lining the intestinal tract and proximal tubule. In the brain and retina, its expression is restricted to astrocytes and Müller cells. SLC5A8 also functions as a tumor suppressor; its expression is silenced in tumors of colon, thyroid, stomach, kidney, and brain. The tumor-suppressive function is related to its ability to mediate concentrative uptake of butyrate, propionate, and pyruvate, all of which are inhibitors of histone deacetylases. SLC5A8 can also transport a variety of pharmacologically relevant monocarboxylates, including salicylates, benzoate, and γ-hydroxybutyrate. Non-steroidal anti-inflammatory drugs such as ibuprofen, ketoprofen, and fenoprofen, also interact with SLC5A8. These drugs are not transportable substrates for SLC5A8, but instead function as blockers of the transporter. Relatively less is known on the role of SLC5A12 in drug transport

Participation of Local People in the Payment for Forest Environmental Services Program: A Case Study in Central Vietnam

In 2010, Vietnam implemented the payment for forest environmental services (PFES) program that was expected to bring additional income to local people and improve the efficiency of forest protection. However, factors affecting the motivation to participate in PFES have rarely been examined. The objectives of this study were to (1) identify factors that influence local people’s participation in PFES, (2) examine how local people participating in the PFES program were involved in decision-making in the Thua Thien Hue Province, and (3) assess PFES impact on local people. We conducted a field survey of 32 households at the study site. We found no difference in the access to PFES between poor and non-poor households. Participation in PFES was considered a reward for labor work in forests and a means to compensate for the legal rights of participants. Local people could participate at many stages of PFES implementation; however, they were only passive spectators with regards to PFES management. Two-thirds of the participants did not participate in decision-making regarding PFES distribution. We conclude that the efficiency of future PFES programs may be increased by enabling and stimulating the participants to take a more active part in the process of PFES management and distribution

Participation of Local People in the Payment for Forest Environmental Services Program: A Case Study in Central Vietnam

In 2010, Vietnam implemented the payment for forest environmental services (PFES) program that was expected to bring additional income to local people and improve the efficiency of forest protection. However, factors affecting the motivation to participate in PFES have rarely been examined. The objectives of this study were to (1) identify factors that influence local people’s participation in PFES, (2) examine how local people participating in the PFES program were involved in decision-making in the Thua Thien Hue Province, and (3) assess PFES impact on local people. We conducted a field survey of 32 households at the study site. We found no difference in the access to PFES between poor and non-poor households. Participation in PFES was considered a reward for labor work in forests and a means to compensate for the legal rights of participants. Local people could participate at many stages of PFES implementation; however, they were only passive spectators with regards to PFES management. Two-thirds of the participants did not participate in decision-making regarding PFES distribution. We conclude that the efficiency of future PFES programs may be increased by enabling and stimulating the participants to take a more active part in the process of PFES management and distribution