J‐curve association between alcohol intake and varicose veins in Japan: The Shimane CoHRE Study

The effect of alcohol intake on varicose veins (VV) has not been determined by its consumption level. The aim of this study was to investigate the association between alcohol intake and VV in an elderly general population. Using a cross‐sectional approach, the Shimane CoHRE Study data, comprising a total of 1060 participants, were analyzed. By multivariate regression analysis adjusted with basic characteristics, past work history, lifestyle‐related factors and medical history, compared with non‐drinkers, mild drinkers (<20.0 g/day) showed a significantly lower adjusted odds ratio (aOR) of VV (aOR = 0.64, P = 0.036). In a similar way, regular drinkers (1–5 days/week) showed a significantly lower aOR of VV when compared with occasional drinkers (aOR = 0.57, P = 0.032). VV and alcohol intake showed J‐curve relationships. In a stratified analysis by alcohol consumption levels, the association of smoking and VV were also observed in moderate to heavy drinkers and habitual drinkers. These findings can provide better understanding of pathophysiological mechanism and be used for evidence‐based patient education.     

Long-term pulmonary function after major lung resection

The function of the remaining lungs after major lung resection may be a determinant of the early postoperative outcome, as well as the late postoperative quality of life of the patient. Thus, extensive efforts have been made to accurately estimate the postoperative pulmonary function using a variety of methods: the segment counting method is utilized in patients without parenchymal diseases, while the functional lung imaging technique may be useful in patients with heterogeneous anatomical lung diseases. The postoperative pulmonary function is influenced not only by the extent of parenchymal resection, but also by various other factors, such as the site of resection, the mode of thoracotomy, the severity of pulmonary emphysema and/or the postoperative progression of pulmonary fibrosis. Although thoracoscopic surgery or segmental resection can lessen the extent of chest wall damage or the extent of parenchymal resection compared with conventional operations, the resulting functional benefits do not last. Interestingly, the postoperative pulmonary function continues to improve during the first postoperative year as if the remaining lungs grow, although the cause(s) of this compensatory response of the remaining lungs remains unclear. Such an ability of the remaining lung to compensate for the lost lung function may eventually determine the late postoperative pulmonary function.     

Impression pressures against teeth in a partially edentulous model with a mobile tooth: influence of impression tray design

The purpose of the present study was to examine the effect of custom tray designs on local pressures against teeth during the impression procedure. In a previous study, a partially edentulous simulation model with a mobile tooth was used, and the effect of custom tray designs on the displacement of the mobile tooth was examined during the impression procedure. Based on that study's results, we have assumed that the differences in impression pressures between the labial and the lingual sides of a mobile tooth could either cause or affect displacement. The present study was undertaken to determine the local impression pressures against each side of three anterior teeth, including one mobile tooth, using the same simulation model and the same custom trays as in the previous study. It was found that the local pressures exerted against teeth during the impression procedure were affected by the custom tray designs and varied according to the coronal shape, axis inclination and location of the teeth.     

Reduction of connexin 43 expression in aged human dental pulp

AIM: To investigate the expression of connexin 43 (CX43) mRNA in young and old human dental pulp tissues to determine the characteristics of CX43 expression. METHODOLOGY: Samples were obtained from human dental pulp of healthy young (17-23 years) and aged (>50 years) subjects. CX43 expression was determined by RT-PCR and by quantitative real-time RT-PCR (QRT-PCR). The threshold cycle (Ct) value, which reflects the amount of PCR, was calculated and the difference between value in the young pulp and that in the aged pulp was statistically analysed. RESULTS: RT-PCR analysis of human dental pulp tissue detected CX43 mRNA in all the samples. CX43 was abundantly expressed in young adult dental pulp, but expression of CX43 mRNA was dramatically decreased in aged human dental pulp. QRT-PCR analysis also showed the reduced expression of CX43 in aged pulp, and expression of CX43 in young pulp was significantly higher (about 10-fold, P < 0.01, Mann-Whitney U-test). CONCLUSION: Reduction of CX43 expression may be associated with the loss of viability in human dental pulp, and is considered as one characteristic of aged pulp.     

Dietary l-Lysine Prevents Arterial Calcification in Adenine-Induced Uremic Rats

Vascular calcification (VC) is a life-threatening complication of CKD. Severe protein restriction causes a shortage of essential amino acids, and exacerbates VC in rats. Therefore, we investigated the effects of dietary l-lysine, the first-limiting amino acid of cereal grains, on VC. Male Sprague-Dawley rats at age 13 weeks were divided randomly into four groups: low-protein (LP) diet (group LP), LP diet+adenine (group Ade), LP diet+adenine+glycine (group Gly) as a control amino acid group, and LP diet+adenine+l-lysine·HCl (group Lys). At age 18 weeks, group LP had no VC, whereas groups Ade and Gly had comparable levels of severe VC. l-Lysine supplementation almost completely ameliorated VC. Physical parameters and serum creatinine, urea nitrogen, and phosphate did not differ among groups Ade, Gly, and Lys. Notably, serum calcium in group Lys was slightly but significantly higher than in groups Ade and Gly. Dietary l-lysine strongly suppressed plasma intact parathyroid hormone in adenine rats and supported a proper bone-vascular axis. The conserved orientation of the femoral apatite in group Lys also evidenced the bone-protective effects of l-lysine. Dietary l-lysine elevated plasma alanine, proline, arginine, and homoarginine but not lysine. Analyses in vitro demonstrated that alanine and proline inhibit apoptosis of cultured vascular smooth muscle cells, and that arginine and homoarginine attenuate mineral precipitations in a supersaturated calcium/phosphate solution. In conclusion, dietary supplementation of l-lysine ameliorated VC by modifying key pathways that exacerbate VC.Medial vascular calcification is common in aging, diabetes, and CKD.^1–4 Because the presence of vascular calcification is strongly associated with increased cardiovascular morbidity and mortality, several studies in both animals and humans have sought ways to reduce the extent of vascular calcification.^5–10 However, satisfactory therapies have not yet been established.¹¹Adenine-induced renal failure is one of the commonly used animal models for studying the development of vascular calcification, but the prevalence of vascular calcification in this model is not very high. Indeed, Price et al. reported that vascular calcification was detected in only 30% of rats with adenine-induced chronic renal failure (adenine rats) fed a normal-protein diet.⁵ These authors speculated that consistent vascular calcification might require a longer period of adenine feeding. On the basis of this idea, they designed a low-protein (LP) diet in an attempt to reduce the nitrogen load and thus enable the rats to thrive on the adenine diet for longer periods. As a result of this attempt, Price et al. unexpectedly found that adenine rats fed a LP diet had extensive vascular calcification without a longer feeding period.⁵ All 13 adenine rats fed the LP diet had uniform alizarin red staining of the aorta, whereas only 3 of the 11 adenine rats fed a normal-protein diet had partial calcification.⁵ These findings indicated that dietary protein deficiency correlates with the extent of vascular calcification.Proteins are usually made from 20 kinds of amino acids. On the basis of nutritional requirements, these amino acids can be divided into two groups: essential amino acids (EAAs) and non-EAAs. Because restriction of dietary protein results in a shortage of EAAs, the level of dietary EAAs may be relevant to the extent of vascular calcification. Among nine EAAs, this study focused on l-lysine (l-Lys) based on the following three reasons. First, l-Lys is the first-limiting amino acid in most cereal grains.¹² Second, the safety of l-Lys supplementation has been verified in the area of animal husbandry. l-Lys has long been added to feed grains in order to improve the utility of feed proteins.¹³ Third, several studies have demonstrated that dietary supplementation with l-Lys protects bones from osteoporosis, a pathologic condition that often coexists with vascular calcification.^14,15 These points prompted us to hypothesize that supplementation with l-Lys would ameliorate vascular calcification. Therefore, in this study, we tested this hypothesis using adenine rats.