Marriage behavior response to prime-age adult mortality: Evidence from Malawi

"This paper examines the effect of AIDS-related mortality of the prime-age adult population on marriage behavior among women in Malawi. A rise in prime-age adult mortality increases risks associated with the search for a marriage partner in the marriage market. A possible behavioral change in the marriage market in response to an increase in prime-age adult mortality is for marriage to occur earlier to avoid women's exposure to HIV/AIDS risks under the condition that the risks are higher during singlehood. We test this hypothesis using micro data from Malawi, where prime-age adult mortality has drastically increased. In the analysis, we estimate prime-age adult mortality that sample women have observed during the adolescent period by utilizing retrospective information on the death of their siblings. Empirical analysis shows that excess prime-age adult mortality observed in the local marriage market (district) lowers the marriage age for females and reduces their premarital sexual activities. Since a lower age for first marriage implies less schooling completed, we expect that the average schooling achievement among women would decline. This behavioral change also implies a longer reproduction period during their marriage, which may lead to a higher fertility rate. However, the second implication should be discounted if the reduction of sexual activities also applies to the married population. Lower schooling attainment among women has further implications on human capital formation in the next generation." from Author's AbstractHIV/AIDS, Marriage, Sexual behavior,

Social learning, selection, and HIV infection: Evidence from Malawi

"This paper examines social learning regarding HIV infection, using HIV test results and sibling death data from Malawi. In the analysis, we compare hypotheses on social learning, selection. and common factors. Empirical results show that young women are less likely to be HIV-infected if they observed prime-age deaths among their siblings, whereas HIV infection is found to be positively related to prime-age sibling deaths among older women. This supports the social-learning hypothesis. Notably, schooling reinforces the social-learning effect of sibling deaths on HIV infection in women regardless of age. The above findings are robust to age (cohort) effects and unobserved location factors." from authors' abstractSocial learning, HIV infection, AIDS (Disease) Africa, Sub-Saharan, siblings,

Fgf20b is required for the ectomesenchymal fate establishment of cranial neural crest cells in zebrafish.

In cranial skeletal development, the establishment of the ectomesenchymal lineage within the cranial neural crest is of great significance. Fgfs are polypeptide growth factors with diverse functions in development and metabolism. Fgf20b knockdown zebrafish embryos showed dysplastic neurocranial and pharyngeal cartilages. Ectomesenchymal cells from cranial neural crest cells were significantly decreased in Fgf20b knockdown embryos, but cranial neural crest cells with a non-ectomesnchymal fate were increased. However, the proliferation and apoptosis of cranial neural crest cells were essentially unchanged. Fgfr1 knockdown embryos also showed dysplastic neurocranial and pharyngeal cartilages. The present findings indicate that Fgf20b is required for ectomesenchymal fate establishment via the activation of Fgfr1 in zebrafish

Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

<p>Abstract</p> <p>Background</p> <p>Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells.</p> <p>Results</p> <p>Adiponectin receptor type 1 (AdipoR1) mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase) was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR), in the cells. AdipoR1 small interfering RNA (siRNA) transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM) in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml) also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively.</p> <p>Conclusion</p> <p>Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.</p

2型糖尿病入院患者の食後血糖値に影響を及ぼす栄養素等の要因

本研究は2型糖尿病患者の食後血糖値に影響する栄養素について明らかにすることを目的とした。対象は入院中の2型糖尿病患者で、食前および食後の血糖測定を実施した22名であった。分析は食後血糖値を従属変数に、エネルギー、たんぱく質、脂質、炭水化物、食物繊維、年齢、BMI、HbA1c、食前血糖値を独立変数とした重回帰分析を用いた。結果は全体としては食後血糖に影響する有意な要因は認められなかった。一方、朝食においてHbA1cと食物繊維に有意な値が認められた。すなわち、2型糖尿病入院患者において、食後血糖値を抑制する栄養素として最も影響を及ぼすのは食物繊維であると考えられる