ABSTRACT.Purpose: To investigate the effect of non-invasive tear stability assessment with forced eye opening on the lower tear meniscus. Methods: Twenty-three eyes of 23 patients with aqueous-deficient dry eye and 23 eyes of 23 normal subjects were enrolled. All subjects underwent imaging with a Keratograph 5M equipped with a modified tear film scanning function. Lower tear meniscus images were captured, and tear meniscus height (TMH) was measured with an integrated ruler before and after non-invasive Keratograph break-up time (NIKBUT) measurements in each subject. Subjects were instructed to keep their eyes open as long as possible during NIKBUT measurements, and the recording was discontinued at the next blink. Results:The TMH values of the normal and dry eye groups were 0.20 AE 0.05 mm and 0.14 AE 0.03 mm, respectively, at baseline. The TMH values of dry eyes were significantly smaller than those of normal eyes (p < 0.001). Significant increases in TMH values were observed in both normal (0.10 AE 0.12 mm) and dry eyes (0.04 AE 0.09 mm) with the NIKBUT measurement (p < 0.001, p = 0.039). A moderate negative correlation was observed between increased TMH and baseline TMH in dry eyes (r = À0.44, p = 0.03), whereas no correlation was observed in normal eyes (r = 0.04, p = 0.85). Conclusions: Forced eye opening required for the non-invasive tear stability assessment influences the TMH measurement possibly due to reflex tear secretion, even in patients with aqueous-deficient dry eye. TMH should be assessed before tests that require forced eye opening.

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This study was aimed to assess the predictability of intraocular lens (IOL) power calculation after cataract surgery for keratoconus. We retrospectively reviewed the clinical charts of 102 eyes of 71 consecutive keratoconic patients who developed cataract. We determined manifest spherical equivalent, prediction errors, and absolute errors, 1 month postoperatively. The achieved refraction was significantly more hyperopic than the targeted refraction, when keratometric readings were used (p = 0.001). At 1 month, 36% and 63% of the eyes were within ±0.5 and ±1.0 D, respectively, of the targeted correction. We found a significant correlation between the prediction error and the mean keratometry (Pearson correlation coefficient r =−0.545, p < 0.001). No vision-threatening complications occurred in any case. The achieved refraction was significantly more myopic than the targeted refraction, when total corneal refractive power was used (p = 0.013). Phacoemulsification with IOL implantation appeared to be safe and effective, and the accuracy was also good in mild keratoconus, but not in severe keratoconus. It should be noted that that a large amount of hyperopic shift occurred especially in advanced keratoconic patients, when keratometric readings were used for IOL power calculation, and that a slight, but significant, myopic shift occurred, when total corneal refractive power was used.

Aging-induced elevation in C1q secretion activates the Wnt signaling pathway in muscles, leading to the development of muscle fibrosis. However, the association between serum C1q level and muscle mass and strength remains unclear in humans. The aim of the study was to elucidate whether serum C1q level is associated with aging- and resistance training-induced changes in muscle mass and strength. First, in a cross-sectional study, we investigated the association between serum C1q level and muscle mass and strength in 131 healthy subjects, aged 20-81 yr. Second, in an intervention study, we examined the association between the effects of serum C1q level and muscle mass and strength on 12 wk resistance training in 11 healthy older adults (60-81 yr). In the cross-sectional study, serum C1q level increased with aging and was negatively correlated with muscle mass and strength. Furthermore, 12 wk resistance training in older adults reduced the age-associated elevation in serum C1q levels. The training effect of serum C1q level significantly correlated with the change in the cross-sectional area of the thigh (r = -0.703; P < 0.01). Serum C1q level may reflect loss of muscle mass; therefore, C1q may be a novel biomarker of sarcopenia.

Abstract. Serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/AGT) is largely located in mitochondria in carnivores, whereas it is entirely found within peroxisomes in herbivores and humans. In rat liver, SPT/AGT is found in both of these organelles, and only the mitochondrial enzyme is markedly induced by glucagon. Although SPT/AGT is a bifunctional enzyme involved in the metabolism of both L-serine and glyoxylate, its contribution to L-serine metabolism is independent of mitochondrial or peroxisomal localization (Xue HH et al., J Biol Chem 274: 16028-16033, 1999). Therefore, the species-specific and food habit-dependent organelle distribution might be required for proper metabolism of glyoxylate at the subcellular site of its formation. Glyoxylate formation from glycolate and that from L-hydroxyproline have been shown to occur in peroxisomes and mitochondria, respectively. The present study found that urinary excretion of oxalate was markedly increased when a large dose of L-hydroxyproline or glycolate was administered to rats. Oxalate formation from L-hydroxyproline but not that from glycolate was significantly reduced when mitochondrial SPT/AGT had been induced by glucagon. The hydroxyproline content of collagen is 10 to 13%, and collagen accounts for about 30% of total animal protein; therefore, these results suggest that an important role of mitochondrial SPT/AGT in carnivores is to convert Lhydroxyproline-derived glyoxylate into glycine in situ, preventing undesirable overflow into the production of oxalate.In herbivores and humans, a major source of glyoxylate, an immediate precursor of oxalate, is believed to be oxidation of glycolate by glycolate oxidase in liver peroxisomes. Glycolate is an intermediate of photorespiration and is thus much higher in content in plants than in animal tissues (1). Glyoxylate is also formed in liver and kidney mitochondria from 4-hydroxy-2-ketoglutarate (HKG), an intermediate of L-hydroxyproline metabolism (2,3). Mitochondrial production of glyoxylate from hydroxyproline is assumed to be significant in carnivores, because the hydroxyproline content of collagen is about 10 to 13% (4) and collagen accounts for about 30% of total animal protein. The major metabolic pathway of hydroxyproline-derived glyoxylate in rat kidney has been suggested to be transamination to glycine (3). Glycine thus formed may be oxidized to CO 2 and ammonia by the mitochondrial glycine cleavage enzyme system, and in conjugation with this oxidation another molecule of glycine is converted to L-serine by mitochondrial serine hydroxymethyltransferase (5). A candidate enzyme responsible for the transamination of glyoxylate to glycine is a dual-functional enzyme, serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/AGT, alternatively named alanine:glyoxylate aminotransferase-1, AGT-1 or serine:pyruvate aminotransferase, SPT). This enzyme was found as SPT (6), and it was later shown to be a predominant enzyme of L-serine metabolism in human, rabbit, and dog livers (7), but its alanine:glyoxylate...