Physiological effects of Shinrin-yoku (taking in the atmosphere of the forest)--using salivary cortisol and cerebral activity as indicators

The purpose of this study is to examine the physiological effects of Shinrin-yoku (taking in the atmosphere of the forest). The subjects were 12 male students (22.8+/-1.4 yr). On the first day of the experiments, one group of 6 subjects was sent to a forest area, and the other group of 6 subjects was sent to a city area. On the second day, each group was sent to the opposite area for a cross check. In the forenoon, the subjects were asked to walk around their given area for 20 minutes. In the afternoon, they were asked to sit on chairs and watch the landscapes of their given area for 20 minutes. Cerebral activity in the prefrontal area and salivary cortisol were measured as physiological indices in the morning at the place of accommodation, before and after walking in the forest or city areas during the forenoon, and before and after watching the landscapes in the afternoon in the forest and city areas, and in the evening at the place of accommodation. The results indicated that cerebral activity in the prefrontal area of the forest area group was significantly lower than that of the group in the city area after walking; the concentration of salivary cortisol in the forest area group was significantly lower than that of the group in the city area before and after watching each landscape. The results of the physiological measurements show that Shinrin-yoku can effectively relax both people's body and spirit.     

Cloning of cDNAs encoding cell-wall hydrolases from pear (Pyrus communis) fruit and their involvement in fruit softening and development of melting texture

'La France' pear ( Pyrus communis L.) fruit stored at 1°C for 1 month (short-term storage) before transfer to 20°C softened and developed a melting texture during ripening, whereas fruit stored for 5 months (long-term storage) before transfer to 20°C softened but did not develop a melting texture. To clarify the mechanisms involved in fruit softening and textural changes, the cDNAs encoding cell-wall hydrolases were isolated by RT-PCR, and their expression and localization were investigated in 'La France' pears. Genes encoding three polygalacturonases (PG; EC 3.2.1.15), four pectin methylesterases (PME; EC 3.1.1.11), one α -arabinofuranosidase (ARF; EC 3.2.1.55), three β -galactosidases (GAL; EC 3.2.1.23), and two endo-1,4- β - d -glucanases (Cel; EC 3.2.1.4) were isolated. Among these 13 isolated genes, PcPG1 was the only gene for which the mRNA expression levels increased in both the short- and long-term stored fruits. This suggested that PcPG1 is involved in fruit softening rather than in the development of the melting texture. In contrast, the expression levels of PcPG3 , PcPME1 , PcPME2 , PcPME3 , PcGAL1 , PcGAL2 , and PcCel2 increased during ripening only in the short-term stored fruit. These genes might thus be involved in the development of the melting texture.     

Upregulation of thromboxane synthase in human colorectal carcinoma and the cancer cell proliferation by thromboxane A2

Tumor growth of colorectal cancers accompanies upregulation of cyclooxygenase-2, which catalyzes a conversion step from arachidonic acid to prostaglandin H(2) (PGH(2)). Here, we compared the expression levels of thromboxane synthase (TXS), which catalyzes the conversion of PGH(2) to thromboxane A(2) (TXA(2)), between human colorectal cancer tissue and its accompanying normal mucosa. It was found that TXS protein was consistently upregulated in the cancer tissues from different patients. TXS was also highly expressed in human colonic cancer cell lines. Depletion of TXS protein by the antisense oligonucleotide inhibited proliferation of the cancer cells. This inhibition was rescued by the direct addition of a stable analogue of TXA(2). The present results suggest that overexpression of TXS and subsequent excess production of TXA(2) in the cancer cells may be involved in the tumor growth of human colorectum.     

Precursor structure of egg proteins in the coral Galaxea fascicularis

In the egg of the reef coral Galaxea fascicularis, four proteins (named GfEP-1 to -4) are stored in high abundance. In the present study, a cDNA containing a full-length open reading frame for GfEP-1 was cloned, and the translated protein sequence was compared to the N-terminal sequences of GfEP-2, -3, and -4. GfEP-1 and -2 were shown to be generated by processing of a precursor of 1439 amino acids, and GfEP-3 turned out to be a partial fragment of GfEP-2. The precursor protein contained regions which exhibited similarities to vitellogenins (Vgs) in bilaterian animals (oviparous vertebrates and invertebrates including nematodes, arthropods, and molluscs). This study reports the first cloning and characterization of a full-length cDNA encoding a Vg in a non-bilaterian animal, and argues that the emergence of Vg as a precursor of egg yolk proteins predated the divergence of the cnidarian and bilaterian lineages.     

Mitochondrial genome of the Komodo dragon: efficient sequencing method with reptile-oriented primers and novel gene rearrangements.

The mitochondrial genome of the Komodo dragon (Varanus komodoensis) was nearly completely sequenced, except for two highly repetitive noncoding regions. An efficient sequencing method for squamate mitochondrial genomes was established by combining the long polymerase chain reaction (PCR) technology and a set of reptile-oriented primers designed for nested PCR amplifications. It was found that the mitochondrial genome had novel gene arrangements in which genes from NADH dehydrogenase subunit 6 to proline tRNA were extensively shuffled with duplicate control regions. These control regions had 99% sequence similarity over 700 bp. Although snake mitochondrial genomes are also known to possess duplicate control regions with nearly identical sequences, the location of the second control region suggested independent occurrence of the duplication on lineages leading to snakes and the Komodo dragon. Another feature of the mitochondrial genome of the Komodo dragon was the considerable number of tandem repeats, including sequences with a strong secondary structure, as a possible site for the slipped-strand mispairing in replication. These observations are consistent with hypotheses that tandem duplications via the slipped-strand mispairing may induce mitochondrial gene rearrangements and may serve to maintain similar copies of the control region.     

Nicotine affects mineralized nodule formation by the human osteosarcoma cell line Saos-2

Several in vitro and in vivo studies have indicated that tobacco smoking may be an important risk factor for the development and severity of inflammatory periodontal disease. In the present study, we examined the effect of nicotine on cell proliferation, alkaline phosphatase (ALPase) activity, mineralized nodule formation, and the expression of extracellular matrix proteins in the human osteosarcoma cell line Saos-2. The cells were cultured with Dulbecco's modified Eagle medium containing 10% fetal bovine serum with 0, 10(-4) M, and 10(-3) M nicotine for up to 14 days. Mineralized nodule formation was examined by alizarin red staining, and the calcium content in mineralized nodules was determined using a calcium E-test kit. The expression of extracellular matrix proteins was estimated by determining the levels of their mRNAs using the real-time polymerase chain reaction. Mineralized nodule formation and calcium content in mineralized nodules were remarkably suppressed by nicotine on days 10 and 14 of culture, respectively. ALPase activity as well as type I collagen and osteopontin expression also decreased in the presence of nicotine after 5, 10, and 14 days of culture, respectively. By contrast, the amount of bone sialoprotein increased during 14 days of culture with nicotine. These results suggest that nicotine suppresses osteogenesis through a decrease in ALPase and type I collagen production by osteoblasts.