The production and characterization of a BoFLC2 introgressed Brassica rapa by repeated backcrossing to an F1.

Flowering time is an important agronomic trait for Brassica rapa crops, and previous breeding work in Brassica has successfully transmitted other important agronomic traits from donor species. However, there has been no previous attempts to produce hybrids replacing the original Brassica FLC alleles with alien FLC alleles. In this paper, we introduce the creation of a chromosome substitution line (CSSL) containing a homozygous introgression of Flowering Locus C from Brassica oleracea (BoFLC2) into a B. rapa genomic background, and characterize the CSSL line with respect to the parental cultivars. The preferential transmission of alien chromosome inheritance and the pattern of transmission observed during the production of the CSSLs are also discussed.

UAV-based individual Chinese cabbage weight prediction using multi-temporal data.

The use of unmanned aerial vehicles (UAVs) has facilitated crop canopy monitoring, enabling yield prediction by integrating regression models. However, the application of UAV-based data to individual-level harvest weight prediction is limited by the effectiveness of obtaining individual features. In this study, we propose a method that automatically detects and extracts multitemporal individual plant features derived from UAV-based data to predict harvest weight. We acquired data from an experimental field sown with 1196 Chinese cabbage plants, using two cameras (RGB and multi-spectral) mounted on UAVs. First, we used three RGB orthomosaic images and an object detection algorithm to detect more than 95% of the individual plants. Next, we used feature selection methods and five different multi-temporal resolutions to predict individual plant weights, achieving a coefficient of determination (R2) of 0.86 and a root mean square error (RMSE) of 436 g/plant. Furthermore, we achieved predictions with an R2 greater than 0.72 and an RMSE less than 560 g/plant up to 53 days prior to harvest. These results demonstrate the feasibility of accurately predicting individual Chinese cabbage harvest weight using UAV-based data and the efficacy of utilizing multi-temporal features to predict plant weight more than one month prior to harvest.

Cisplatin differently affects amino terminal and carboxyl terminal domains of HSP90.

The 90-kDa heat shock protein (HSP90) is a molecular chaperone that assists in the folding and assembly of proteins in the cytosol. We previously demonstrated that the antineoplastic reagent, cisplatin, inhibits the aggregation prevention activity of mammalian HSP90. We now show that cisplatin binds both the amino terminal and carboxyl terminal domains of the human HSP90 and differently affects these two domains. Cisplatin blocks the aggregation prevention activity of HSP90C, but not HSP90N. In contrast, cisplatin induces a conformational change in HSP90N, but not HSP90C. These results indicate that cisplatin modulates the HSP90 activities through two different mechanisms using the two distinct binding sites of the HSP90 molecule.

Intestinal SGLT1-mediated absorption and metabolism of benzyl beta-glucoside contained in Prunus mume: carrier-mediated transport increases intestinal availability.

The intestinal absorption of benzyl beta-glucoside (BNZ beta glc) contained in the fruit of Prunus mume SIEB. et ZUCC. (Rosaceae), which is traditionally used as a medicinal food in Japan, was studied in rat intestines. BNZ beta glc was absorbed from the mucosal to serosal sides. Its metabolite, benzyl alcohol (BAL), was also detected on both the mucosal and serosal sides. In the presence of phloridzin (Na(+)/glucose cotransporter (SGLT1) inhibitor) or in the absence of Na+ (driving force), BNZ beta glc absorption was significantly decreased. Transport clearance of BNZ beta glc across the brush border membrane decreased as its concentration increased. These results indicate that BNZ beta glc is transported by SGLT1. Metabolic clearance of BNZ beta glc also decreased as its concentration increased. The amount ratio of BNZ beta glc to BAL on the serosal side increased with the increase of BNZ beta glc concentration. The intestinal availability of BNZ beta glc was lower in the absence of Na+ than in the presence of Na+, indicating that the SGLT1-mediated transport of BNZ beta glc increases intestinal availability by decreasing the intestinal extraction ratio. This neutraceutical study concluded that intestinal carrier-mediated transport across the brush border membrane improves the intestinal availability of nutritionally, pharmacologically or physiologically active compounds that undergo intestinal metabolism (first-pass effect).

Effect of clinical clerkship on students' attitudes toward medical learning in Japan: a case study at Kinki University School of Medicine.

A 20-item questionnaire was administered to 253 physicians and 111 medical students, who did not have previous clinical clerkship experience, upon completion of their clinical clerkship. Medical students responded that they enjoyed their clinical clerkships but felt pressured and physically tired. Ninety percent of these medical students developed expectations for their career choice during their clinical clerkship. Only 18% of physicians felt that they allowed students enough chance to participate in clinical practice. We must emphasize that the success of any clinical clerkship system depends on an effective communication system between physicians and medical students.

Aberrant increase in cytochrome c oxidase subunit I precedes neuronal death after cerebral ischemia.

Cerebral ischemia is known to produce excessive reactive oxygen species in mitochondria, and these radicals initiate radical chain reactions, causing cellular macromolecule damage, and also promote the mitochondrial apoptosis pathway, ultimately leading to cell death. However, little is known about the mitochondrial functional alterations after ischemia. The authors examined the expression of cytochrome c oxidase (COX), a terminal, rate-limiting enzyme of the electron transport chain to generate ATP, after global cerebral ischemia in rats. Immunofluorescent staining and western blot were performed to investigate the spatial and temporal changes in two important COX subunits: mitochondrion-encoded COX subunit I (COX I) and nucleus-encoded COX subunit IV (COX IV). Under the normal condition, these subunits have to be regulated precisely in a 1 : 1 stoichiometry to assemble the functional COX holoenzyme. In this study, a huge increase in COX I, which is disproportionate to COX IV, was observed in the early stage after lethal ischemia, preceding delayed neuronal death. In contrast, mild sublethal ischemia did not induce obvious changes in COX I and IV. This aberrant increase in COX I may be an early sign of delayed neuronal death or may predict later electron transport chain dysfunction to generate ATP.

Zinc-L-carnosine binds to molecular chaperone HSP70 and inhibits the chaperone activity of the protein.

In this study, we have investigated the specific binding proteins of Zinc-L-carnosine (Polaprezinc) using Polaprezinc-affinity column chromatography in vitro. A protein having a 70-kDa molecular mass was eluted by the linear gradient of 0-1.0 mM Polaprezinc from the affinity column and the protein was identified as the molecular chaperone HSP70 by immunoblotting. The chaperone activity of HSP70 was completely suppressed by Polaprezinc. The ATPase activity of HSP70 was affected to some extent by the reagent. In the circular dichroism (CD) spectrum, the secondary structure of HSP70 was changed in the presence of Polaprezinc, i.e. it decreased in the α-helix. We have determined the Polaprezinc-binding domain of HSP70 by using recombinant HSP70N- and C-domains. Although Polaprezinc could bind to both the N-terminal and the C-terminal of HSP70, the HSP70N-domain has a high affinity to the drug. Regarding the peptide cleavage of the HSP70N- and C-domains with proteinase K, the intact HSP70N still remained in the presence of Polaprezinc. On the other hand, the quantity of the intact C-domain slightly decreased under the same conditions along with the newly digested small peptides appeared. It has been suggested that Polaprezinc binds to HSP70 especially in the N-domains, suppresses the chaperone activity and delays an ATPase activities of HSP70.

The induction mechanism of the molecular chaperone HSP70 in the gastric mucosa by Geranylgeranylacetone (HSP-inducer).

To elucidate the induction mechanism of HSP70 by geranylgeranylacetone (GGA), we investigated GGA specific binding proteins using a GGA-affinity column. Alteration of chaperone activity of HSP70 and binding affinity of HSP70 to heat shock factor-1 (HSF-1) was evaluated in the presence or absence of GGA. The binding domain of HSP70 to GGA was also analyzed. A 70-kDa protein eluted by 10 mM GGA from the GGA-affinity column was identical to constitutively expressed HSP70 on immunoblotting. GGA-binding domain of HSP70 was C-terminal of the protein as peptide-binding domain (HSP70C). The chaperone activity of HSP70 and recombinant HSP70C was suppressed by GGA. Furthermore, dissociation of the HSP70 from HSF-1 was observed in the presence of GGA. GGA preferentially binds to the C-terminal of HSP70 which binds to HSF-1. After dissociation of HSP70, free HSF-1 could acquire the ability to bind to HSE (the promoter region of HSP70) gene.

Effects of benzyl glucoside and chlorogenic acid from Prunus mume on adrenocorticotropic hormone (ACTH) and catecholamine levels in plasma of experimental menopausal model rats.

To investigate the effectiveness of benzyl beta-D-glucopyranoside (BG) and chlorogenic acid (CA), the constituents of the fruit of Prunus mume, for relieving tension in experimental menopausal model rats (M-rats) caused by ether stress, the effects of BG and CA on adrenocorticotropic hormone (ACTH) and catecholamine (adrenaline, noradrenaline, and dopamine) levels were examined in the plasma of M-rats. Caffeic acid, quinic acid, and rosmarinic acid, which are compounds structurally related to CA, were also examined. BG obviously recovered catecholamine levels decreased by ether stress and increased dopamine to high levels. On the other hand, CA significantly decreased the ACTH level increased by ether stress and showed the greatest effect of all compounds. These results suggest that BG and CA may contribute to relieving the tension in M-rats caused by ether stress.

Myocardial ischemia adjacent to infarction enhances the magnitude of exercise-induced ST-segment elevation one month after myocardial infarction.

The aims of this study were to compare exercise-induced ST-segment elevation with and without ischemia and to examine the relation between exercise-induced ST-segment elevation and the location of myocardial ischemia. Seventy-nine patients with first anterior myocardial infarction underwent thallium-201 exercise myocardial scintigraphy test one month after myocardial infarction. There were 37 patients showing no reversible defect (non ischemia group), 33 with reversible defect in the territory of the left descending coronary artery (homozonal ischemia group) and 9 with a reversible defect in the territory of the left circumflex or right coronary artery (remote ischemia group). There were no significant differences among the three groups with respect to infarct size, presence of dyskinesis and exercise endurance time. Patients with homozonal ischemia had the highest degree of ST-segment elevation (0.22 +/- 0.09 mV) followed by patients without ischemia (0.13 +/- 0.07 mV) and those with remote ischemia (0.09 +/- 0.08 mV, P <.01). In conclusion, Myocardial ischemia adjacent to infarction amplifies exercise-induced ST-segment elevation.

73-kDa molecular chaperone HSP73 is a direct target of antibiotic gentamicin.

Although gentamicin (GM) has been used widely as an antibiotic, the specific binding protein of the drug has not yet been understood sufficiently. Here we show that GM specifically associates with the 73-kDa molecular chaperone HSP73 and reduces its chaperone activity in vitro. In the present study, we investigated GM-specific binding proteins using a GM-affinity column and porcine kidney cytosol. After washing the column, only the 73-kDa protein was eluted from the column by the addition of 10 mm GM. None of the other proteins were found in the eluant. Upon immunoblotting, the protein was identical to HSP73. Upon CD spectrum analysis, the binding of GM to HSP73 resulted in a conformational change in the protein. Although HSP73 prevents aggregation of unfolded rhodanese in vitro, the chaperone activity of HSP73 was suppressed in the presence of GM. Using limited proteolysis of HSP73 by TPCK-trypsin, the GM binding site is a COOH-terminal for one third of the protein known to be a peptide-binding domain. During immunohistochemistry, HSP73 and GM were co-localized in enlarged lysosomes of rat kidneys with GM-induced acute tubular injury in vivo. Our results suggest that the specific association between HSP73 and GM may reduce the chaperone activity of HSP73 in vitro and/or in vivo, and this may have an interaction with GM toxicity in kidneys with GM-induced acute tubular injury.