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A new approach to synthesize optically active β-amino-α-hydroxyl acid derivatives via chiral Brønsted acid-Rh(2)(OAc)(4) cocatalyzed three-component reactions of diazo acetates with alcohols and imines is reported. A matched reaction system was identified to give the products in moderate diastereoselectivity and good enantioselectivity. Application of this methodology is demonstrated in the efficient synthesis of a taxol side chain and (-)-epi-cytoxazone.

Purpose: To investigate changes in protein profiles of posterior sclera in guinea pigs during development of form deprivation myopia and recovery., Methods: Three groups of guinea pigs (developing form deprivation myopia, recovering from the myopia and normal control) were evaluated for protein profiles of the posterior sclera using two-dimensional gel electrophoresis. Protein spots with a different intensity of at least threefold among the 3 groups were further identified with mass spectrometry. Key proteins associated with ocular growth (crystallins) were examined at mRNA levels using RT-PCR., Results: Moderate myopia was induced at 7 weeks of monocular deprivation and then more gradually recovered toward the previous refractive status 4 days after re-exposure of the eye to normal visual conditions. The profile of all protein spots at the posterior sclera was similar for both the deprived and the recovery eyes but distinct between either of the 2 experimental eyes and the normal control eyes. Twenty-six and 33 protein spots were differentially expressed in the deprived and the recovery eyes, respectively, compared to the normal control eyes. In contrast, the number of proteins differentially expressed between the deprived and the recovery eyes was only 5. Among the different subtypes of crystallins, βB2-crystallin was down-regulated and βA4-crystallin was upregulated in the deprived eyes at both protein and mRNA levels compared to the normal control eyes. The trend of expression for βA3/A1-crystallin was also similar at both mRNA and protein levels for the deprived eyes. However, αA-crystallin mRNA in the recovery eyes was upregulated while αA-crystallin itself was down-regulated. A similar inconsistency in expression of βA3/A1-, βA4-, and βB2-crystallins between the protein and mRNA levels also occurred in the recovery eyes., Conclusions: Proteomic analysis provides a useful survey of the number of proteins whose levels change during form deprivation myopia and the subsequent recovery. In particular, the crystallins changed during the development of form deprivation myopia and recovery. The changes in crystallin protein levels were consistent with that in mRNA levels during the development stage of form-deprivation myopia (FDM). However, the changes of most crystallin protein levels were mismatched with mRNA levels during the recovery stage.

Purpose: To critically evaluate whether the adenosine A2A receptor (A2AR) plays a role in postnatal refractive development in mice., Methods: Custom-built biometric systems specifically designed for mice were used to assess the development of relative myopia by examining refraction and biometrics in A2AR knockout (KO) mice and wild-type (WT) littermates between postnatal days (P)28 and P56. Ocular dimensions were measured by customized optical coherence tomography (OCT), refractive state by eccentric infrared photorefraction (EIR), and corneal radius of curvature by modified keratometry. Scleral collagen diameter and density were examined by electron microscopy on P35. The effect of A2AR activation on collagen mRNA expression and on soluble collagen production was examined in cultured human scleral fibroblasts by real-time RT-PCR and a collagen assay kit., Results: Compared with WT littermates, the A2AR KO mice displayed relative myopia (average difference, 5.1 D between P28 and P35) and associated increases in VC depth and axial length from P28 to P56. Furthermore, the myopic shift in A2AR KO mice was associated with ultrastructural changes in the sclera: Electron microscopy revealed denser collagen fibrils with reduced diameter in A2AR KO compared with WT. Last, A2AR activation induced expression of mRNAs for collagens I, III, and V and increased production of soluble collagen in cultured human scleral fibroblasts., Conclusions: Genetic deletion of the A2AR promotes development of relative myopia with increased axial length and altered scleral collagen fiber structure during postnatal development in mice. Thus, the A2AR may be important in normal refractive development.

A micellar electrokinetic capillary chromatography (MEKC) method has been developed for simultaneous determination of 10 bioactive flavonoids: rutin, apigenin, luteolin, eriodictyol, kaempferol, chrysin, acacetin, flavanone, flavone, and fisetin. The effect of several parameters, such as UV detection wavelength, buffer pH, buffer concentration, sodium dodecyl sulfate (SDS) concentration, beta-cyclodextrin (beta-CD) concentration, separation voltage, and injection time on the separation of these flavonoids were systematically investigated. The 10 flavonoids were successfully separated within 18 min in 20 mM Na(2)B(4)O(7)-10 mM NaH(2)PO(4) buffer (pH 9.7) containing 100 mM SDS and 16 mM beta-CD at a separation voltage of 19 kV, with UV detection at 254 nm. Regression analysis revealed a good linear relationship between the peak area of each analyte and its concentration with detection limits (S/N = 3), ranging from 0.15 to 1.36 microg mL(-1). This method could simultaneously quantify the 10 flavonoids and be used in the quality control of functional foods containing propolis and Ginkgo biloba.

Purpose: To characterize and compare gene expression patterns of the whole eyeball among human, mouse, and guinea pig based on expressed sequence tags (ESTs)., Methods: Approximately 10,000 clones were sequenced from the 5'-end for each cDNA library made from mRNAs isolated from whole eyeballs of human, mouse, and guinea pig. ESTs were assembled and analyzed based on standard methods., Results: We acquired 31,464 high-quality ESTs including 9,949 for the human, 11,495 for the mouse, and 10,020 for the guinea pig cDNA libraries, which were clustered into 12,253 unigenes for all three species. After removal of non-mRNA contaminations, we were able to match 96%, 97%, and 63% of the human, mouse, and guinea pig unigenes to sequences in the nonredundant library in GenBank, respectively. The high-abundance and medium-abundance genes in each library correlate with the anatomic structure and physiologic function of the eye in the three species. The large contribution from the lens in the mouse was related to the abundance of crystallin. Differentially expressed genes were observed among three libraries. Some of them appeared species-specific., Conclusions: According to their gene expression patterns, guinea pig and human eyes are more similar compared to those of the mouse, making the guinea pig a promising animal model for eye research.