Effect of benign prostatic hyperplasia on the development of spine, hip, and wrist fractures

Benign prostatic hyperplasia is one of the most common diseases in the elderly male population. The urinary tract symptoms may increase the risk of falls and fractures. The results indicated that patients with benign prostatic hyperplasia could increase the risk of vertebral compression fractures in both the thoracic and lumbar spine and also hip fractures, but did not increase the risk of wrist fracture.

INTRODUCTION

The relationship between benign prostatic hyperplasia and the development of fall-related fractures, especially vertebral compression fractures, has been seldom mentioned in the literature. This study aimed to evaluate the risk of developing vertebral compression fracture, hip fracture, and wrist fracture in patients with benign prostatic hyperplasia.

METHODS

This study obtained claims data retrospectively from the National Health Insurance Research Database of Taiwan and identified 48,114 patients who were diagnosed as having benign prostatic hyperplasia. Subjects of the control cohort were individually matched at a ratio of 4:1 with those in the benign prostatic hyperplasia cohort according to age and the index day. Comorbidities were classified as those existing before the index day and included a previous fracture history, osteoporosis, myocardial infarction, congestive heart failure, diabetes mellitus, hypertension, cerebrovascular accident, etc. The end of the follow-up period of the analyses was the day when the patient developed new vertebral compression fractures, hip fractures, or wrist fractures, terminated enrollment from the National Health Insurance, or died or until the end of 2012. The study used the Cox proportion hazard model to determine the hazard ratio for developing new hip fractures.

RESULTS

Patients with benign prostatic hyperplasia were significantly more likely than those in the control cohort to develop new vertebral compression fractures in the thoracic spine (0.43% vs. 0.40%, adjusted hazard ratio 3.03, confidence interval 2.12-4.31) and lumbar spine (1.26% vs. 1.23%, adjusted hazard ratio 4.12, confidence interval 3.39-5.01), and hip fracture (1.47% vs. 2.09%, adjusted hazard ratio 1.22, confidence interval 1.10-1.36), but does not increase the risk of wrist fracture (0.61% vs. 0.67%, adjusted hazard ratio 1.07, confidence interval 0.85-1.34).

CONCLUSIONS

Patients with benign prostatic hyperplasia exhibited an increased risk of developing vertebral compression fractures in both the thoracic and lumbar spine and also hip fractures, but did not increase the risk of wrist fracture. However, more research is needed to confirm this trend in the clinical setting.

A Point-based Mortality Prediction System for Older Adults with Diabetes

The mortality prediction models for the general diabetic population have been well established, but the corresponding elderly-specific model is still lacking. This study aims to develop a mortality prediction model for the elderly with diabetes. The data used for model establishment were derived from the nationwide adult health screening program in Taiwan in 2007-2010, from which we applied a 10-fold cross-validation method for model construction and internal validation. The external validation was tested on the MJ health screening database collected in 2004-2007. Multivariable Cox proportional hazards models were used to predict five-year mortality for diabetic patients ≥65 years. A total of 220,832 older subjects with diabetes were selected for model construction, of whom 23,241 (10.5%) died by the end of follow-up (December 31, 2011). The significant predictors retained in the final model included age, gender, smoking status, body mass index (BMI), fasting glucose, systolic and diastolic blood pressure, leukocyte count, liver and renal function, total cholesterol, hemoglobin, albumin, and uric acid. The Harrell's C in the development, internal-, and external-validation datasets were 0.737, 0.746, and 0.685, respectively. We established an easy-to-use point-based model that could accurately predict five-year mortality risk in older adults with diabetes.

A Study of the Surface Texture of Polycrystalline Phosphor Films Using Atomic Force Microscopy

Stimulable phosphor thin films are being investigated for use as optical data storage media. We have successfully applied atomic force microscopy (AFM) to the measurement of the surface texture of these films. Determination of the surface texture of the films is important for evaluating the effect of surface quality on optical scatter. In other thin film material systems it has been found that the surface “bumps” revealed by AFM correspond to grains in the film. This is not the case for the stimulable phosphor films used in our study. We have determined the grain size of our phosphor films by transmission electron microscopy (TEM) and x-ray diffraction (XRD). The grain size from TEM and XRD does not correlate with the size of the AFM surface “bumps.” For example, in two of the five films studied, the XRD derived grain size varies by a factor of two but the size of the surface “bumps” remains the same. We conclude that the texture of the film surface is not directly determined by the grain size of the phosphor material.

The alkaloids of Artabotrys uncinatus

A novel type of alpha,beta-butenolide alkaloid, uncinine (1), two novel oxoaporphines, artabonatine C (2) and artabonatine D (3), a new oxazoloaporphine, artabonatine E (4), and a new 7,7'-bisdehydroaporphine, artabonatine F (5), along with 25 known alkaloids, were isolated from Artabotrys uncinatus. The structures of 1-5 were determined using NMR and mass spectral data. Atherospermidine and squamolone exhibited cytotoxicity against hepatocarcinoma cancer cell lines (Hep G(2) and 2,2,15), and the activity of some of the alkaloids in an antithrombin assay is also discussed.

Cytotoxic constituents of the fruits of Cananga odorata

A new guaipyridine sesquiterpene alkaloid, cananodine (1), and two new eudesmane sesquiterpenes, cryptomeridiol 11-alpha-L-rhamnoside (2) and gamma-eudesmol 11-alpha-L-rhamnoside (3), along with gamma-eudesmol (4), were isolated from the fruits of Cananga odorata. The structures of compounds 1-3 were established on the basis of NMR and MS methods. In addition, compounds 1-4 and four previously reported alkaloids, cleistopholine (5), N-trans-feruloyltyramine (6), (+)-ushinsunine-beta-N-oxide (7), and lyscamine (8), were evaluated for cytotoxicity against two human hepatocarcinoma cell lines.

Cytotoxic constituents of Polyalthia longifolia var. pendula

A new halimane diterpene, 3beta,5beta, 16alpha-trihydroxyhalima-13(14)-en-15,16-olide (1), and a new oxoprotoberberine alkaloid, (-)-8-oxopolyalthiaine (2), along with 20 known compounds, were isolated from a methanolic extract of Polyalthia longifolia var. pendula. The structures of compounds 1 and 2 were established by spectroscopic analysis. Several of these compounds were evaluated for cytotoxicity toward a small panel of human cell lines.

Increased frequency of angiotensin-converting enzyme DD genotype in patients with type 2 diabetes in Taiwan

BACKGROUND

Diabetes is one of the major causes of end-stage renal failure in the Taiwanese population. Previous studies have shown that angiotensin-converting enzyme (ACE) inhibitor can improve glucose utilization and suppress hepatic glucose production and the renin-angiotensin system may play an important role in the initiation and progression of diabetic nephropathy. Thus, ACE gene polymorphism may be associated with type 2 diabetes and diabetic nephropathy.

METHODS

To investigate the distribution of ACE-I/D genotype in type 2 diabetes and diabetic nephropathy, we examined 336 patients with type 2 diabetes (157 without nephropathy and 179 with nephropathy) and 263 age-matched normal controls. The diagnosis of nephropathy was made when daily protein loss exceeded 500 mg. ACE gene polymorphism was analysed by use of polymerase chain reaction.

RESULTS

Our study revealed that the frequency of the D allele of the ACE gene was 29.3% in normal controls. The frequency of ACE DD genotype was significantly higher in type 2 diabetics compared with normal controls (18.2 vs 9.1%, P<0.01). The frequency of ACE DD genotype in patients with diabetic nephropathy was significantly higher than in patients without nephropathy (22.3 vs 13.4%, P<0.05). To determine whether ACE gene polymorphism was associated with the severity of diabetic nephropathy, we divided patients with diabetic nephropathy into dialysis and non-dialysis groups. The frequency of ACE DD genotype in the dialysis group was significantly higher than in non-dialysis group (28.7 vs 15.3%, P<0.05).

CONCLUSION

Our results indicate that the frequency of ACE DD genotype is markedly higher in patients with type 2 diabetes, and the ACE DD genotype is significantly associated with diabetic nephropathy.

Increased renal medullary endothelin-1 synthesis in prehypertensive DOCA- and salt-treated rats

To investigate the role of renal endothelin-1 (ET-1) synthesis in water-sodium homeostasis, we measured mRNA expressions, protein levels, enzyme activity, and receptor binding of the renal ET-1 system in a DOCA- and salt-treated rat model. Male Wistar rats were divided into control and DOCA- and salt-treated (DOCA-Salt) groups. The DOCA-Salt group received 25 mg/kg body wt DOCA and was maintained on 1% NaCl drinking water. Rats were killed on days 1, 2, 4, and 10 of the experiment. Urinary ET-1-like immunoreactivity significantly increased from the second day in the DOCA-Salt group and correlated well with the urinary sodium excretion rate (r = 0.81, P < 0.001). Renal endothelin-converting enzyme (ECE) activity, ET-1, and ECE-1 mRNA expressions were significantly increased in the renal medullary area of DOCA-Salt rats. In situ hybridization and immunohistochemical studies showed that the increase in ET-1 synthesis was mainly localized in the inner medullary collecting ducts. The maximum binding of endothelin B receptor also increased from the second day in the renal medulla of the DOCA-Salt group. Our results suggest that renal medullary synthesized ET-1 may be a natriuretic factor and may participate in the intrarenal regulation of water and salt homeostasis in prehypertensive DOCA-and salt-treated rats.

Decreased GTPase activity of K-ras mutants deriving from human functional adrenocortical tumours

Our previous studies have shown that seven out of 15 patients with adrenocortical tumours contained K-ras gene mutation. In addition, the mutation type was a multiple-site mutation, and the hot spots were located at codons 15, 16, 18 and 31, which were different from those reported before (codons 12, 13 and 61). To understand whether the mutation hot spots in human adrenocortical tumours were associated with activation of K-Ras oncogene and the alterations of its biocharacteristics, mutant K-Ras genes were cloned from tumour tissues and then constructed with expression vector pBKCMV. Mutant K-Ras genes were expressed at high levels in Escherichia coli and the resultant K-Ras proteins were shown to be functional with respect to their well-known specific, high-affinity, GDP/GTP binding. The purified K-Ras protein from E. coli were then measured for their intrinsic GTPase activity and the GTPase activity in the presence of GTPase-activating protein for Ras. The results showed that the wild-type cellular K-Ras protein (p21BN) exhibits about ten times higher intrinsic GTPase activity than the activated protein (p21BM3) encoded by mutant K-Ras gene, which mutated at codon 60. With regards to the codon 15, 16, 18 and 31 mutant K-Ras proteins (p21BM2), the GTPase activity in the presence of GAP is much lower than that of the normal K-Ras protein, whereas the intrinsic GTPase activity is nearly the same as that of the normal K-Ras protein. These results indicated that mutations at these hot spots of K-Ras gene were indeed activated K-Ras oncogene in adrenocortical tumours; however, their association with tumors needs further experiments to prove.

Two new alkaloids from artabotrys uncinatus

A novel oxazoloaporphine, artabonatine A (1), and a new 7-hydroxyaporphine, artabonatine B (2), have been isolated and characterized from the fresh unripe fruits of Artabotrys uncinatus, along with five known compounds. Structure elucidation of 1 and 2 was based on UV, IR, NMR, and MS analyses.

Increased renal ANP synthesis, but decreased or unchanged cardiac ANP synthesis in water-deprived and salt-restricted rats

BACKGROUND

Experiments were performed to examine the effect of water deprivation and salt restriction on ANP synthesis in the kidneys and hearts of normal rats.

METHODS

A 4-day water deprivation (WD) and 7-day salt restriction (SR; 0.01% NaCl) were performed in 12 and 14 rats, respectively. Atrial natriuretic peptide (ANP) mRNA expression in the kidney was assessed with reverse transcription-polymerase chain reaction coupled with Southern blot hybridization, while the ANP mRNA in the hearts was measured by Northern blot hybridization. ANP and angiotensin II concentrations in the extracted plasma were measured by radioimmunoassay. The molecular form of renal ANP-like protein was characterized by reverse phase-high-performance liquid chromatography (RP-HPLC).

RESULTS

Renal outer and inner medullary ANP mRNA showed a respective 11-fold and ninefold increase in WD rats, and an eightfold and fivefold increase in SR rats as compared to corresponding control groups. Inversely, cardiac atrial ANP mRNA and plasma ANP were decreased in WD rats, whereas they did not change in the SR group. Plasma angiotensin II concentration increased in conjunction with the decrease of urine sodium excretion in both groups. RP-HPLC analysis revealed a 45% extraction of ANP in the WD rat kidneys, whereas only 3% ANP in the control kidneys migrated in a molecular form similar to cardiac atrial proANP.

CONCLUSIONS

Our results demonstrate that water deprivation and salt restriction markedly enhance renal ANP mRNA, whereas water deprivation suppresses cardiac atrial ANP mRNA and plasma ANP concentrations. The current study indicates that renal ANP and cardiac atrial ANP appear to be two distinct systems regulated by different mechanisms and possibly exhibiting different intra-renal paracrine and systemic endocrine functions.

Circadian rhythm of urinary endothelin-1 excretion in mild hypertensive patients

Endothelin-1 (ET-1) is a potent vasoconstrictive peptide with diverse physiologic actions and has been considered to be involved in the pathogenesis of hypertension. We sought to investigate the role of renal synthesis of ET-1 in the regulation of daily sodium homeostasis and the possible contribution of renal synthesized ET-1 in the pathogenesis of essential hypertension (EHT). Urinary ET-1-like immunoreactivity (ET-1-L1) was measured by a radioimmunoassay after extraction in 23 EHT patients without detectable target organ damage, and in 11 normotensive controls. All study subjects received a controlled diet during an 8-day study period. Urinary and blood samples were collected by four sampling periods/day from the 4th to 6th days, and on the 7th day, study subjects were given an intravenous infusion of 1250 mL normal saline over 2 h. In the basal state, the urinary sodium and ET-1-L1 excretions showed diurnal patterns in both the normal and hypertensive groups, and urinary ET-1-L1 excretion rate correlated well with urinary sodium excretion rate. There were no differences found in plasma ET-1 levels, urinary ET-1-L1, and sodium excretion rates between the control and hypertensive groups. After saline infusion, ten hypertensive patients showed nonexaggerated natriuresis, and the 24-h urinary ET-1-L1 excretion (47.0+/-4.0 pmol/day), collected during the day of saline infusion, was significantly lower than that of the control group (86.3+/-10.0 pmol/day) or the exaggeratedly natriuretic hypertensive patients (91.7+/-8.4 pmol/ day). Our results suggest that renal ET-1 may be responsible for the renal handling of sodium homeostasis, and alteration of renal ET-1 synthesis may be a contributory factor in the pathogenesis of essential hypertension and salt sensitivity.

Increased atrial natriuretic peptide mRNA expression in the kidney of diabetic rats

To investigate whether renal synthesis of atrial natriuretic peptide (ANP) is influenced in diabetes, we measured renal ANP mRNA levels, urine volume, urinary ANP and sodium excretion rates in streptozotocin (STZ)-induced diabetic rats. By using reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blot analysis, we found that renal cortical and outer medullary ANP mRNA levels in untreated diabetic rats were markedly increased as early as the second day after the onset of hyperglycemia and remained elevated for the entire 42-day study period. Plasma ANP concentrations in untreated diabetic rats were increased on the 42nd day, whereas plasma renin activity were suppressed. The urine volume, urinary ANP and sodium excretion rates in untreated diabetic rats were also significantly elevated on the second day and remained elevated for the entire 42-day study period. Urinary ANP excretion rates were well correlated with urine volume, and urinary sodium excretion rate in normal rats and diabetic rats on days 2, 4, 7, 14 and 42. Our results indicate that renal ANP mRNA expression is enhanced in diabetic rats, and that renal-synthesized ANP as one of regulators to handle water and sodium balance in diabetic rats is worthy of further investigation.

Increased renal atrial natriuretic peptide synthesis in rats with deoxycorticosterone acetate-salt treatment

To investigate the role of renal synthesis of atrial natriuretic peptide (ANP) as a contributor to the water-sodium homeostasis, we studied the effects of electrolyte-water imbalance on renal ANP mRNA levels, plasma ANP concentrations, and urinary ANP excretion rates by using reverse transcription-polymerase chain reaction (PCR) and radioimmunoassay. Male Wistar rates divided into the following three groups: 1) the control group, 2) deoxycorticosterone acetate (DOCA)-salt-treated group, and 3) low-salt-treated group. The urinary sodium excretion rate and urine volume in the DOCA-salt rats were significantly elevated at 2 days and for the 10-day study. The urinary ANP excretion rate in DOCA-salt rats was significantly increased at 2 days after treatment and was well correlated to the urinary sodium excretion rate (r = 0.76, P < 0.01). Plasma ANP levels in the DOCA-salt rats were elevated on the day of death. In contrast, plasma renin activities were markedly suppressed in DOCA-salt rats and increased in low-salt rats. By immunohistochemical study, immunoreactive ANP materials were mainly localized in the proximal and distal cortical tubules of the kidney. With the PCR cloning and sequencing technique, ANP cDNA was cloned from the rat kidney, and the sequences were identical to that of ANP identified in the atria. By semiquantitative PCR technique, the expression of ANP mRNA in the ventricle and renal cortex tissues was significantly enhanced in the DOCA-salt rats. Our results confirm that the rat kidney is a site of ANP synthesis and indicate that renal ANP synthesis is enhanced in a volume-expansion state. We propose that renal synthesized natriuretic peptide participates in the intrarenal regulation of water-electrolyte homeostasis and may contribute to renal adaptation during the mineralocorticoid escape phenomenon.