Poor glycemic control and decreased renal function are associated with increased intrarenal RAS activity in Type 2 diabetes mellitus.

AIMS: The renin-angiotensin system (RAS) plays an important role in the pathogenesis of diabetic nephropathy. The aim of the present study was to investigate intrarenal RAS activity in patients with type 2 diabetes (T2DM). METHODS: We measured urinary angiotensinogen, a reliable biomarker of intrarenal RAS activity, in 14 controls without T2DM, 25 T2DM patients without nephropathy, 11 chronic kidney disease (CKD) patients without T2DM and 46 CKD patients with T2DM. Associations between urinary angiotensinogen and clinical parameters were examined. RESULTS: Compared with the controls, urinary [angiotensinogen:creatinine] were significantly higher in T2DM patients without nephropathy (4.70 ± 2.22 vs. 8.31 ± 5.27 µg/g, p=0.037). Age, hemoglobin A1c (HbA1c) and fasting plasma glucose correlated significantly and positively with the log{urinary [angiotensinogen:creatinine]} (r=0.632, p=0.007; r=0.405, p=0.027; r=0.583, p=0.003, respectively) in T2DM patients without nephropathy. In contrast, the urinary [angiotensinogen:creatinine] were not significantly different between CKD patients with and without T2DM (22.7 ± 27.8 vs. 33.5 ± 40.8 µg/g, p=0.740); although they were significantly higher when compared with non-CKD patients. In the CKD patients with T2DM systolic blood pressure, serum creatinine, estimated glomerular filtration rate and urinary [albumin:creatinine] correlated significantly with the log{urinary [angiotensinogen:creatinine]} (r=0.412, p=0.004; r=0.308, p=0.037; r=-0.382, p=0.001; r=0.648, p<0.001, p<0.001, respectively). CONCLUSIONS: Our findings indicate that poor glycemic control is significantly associated with intrarenal RAS activity in T2DM patients without nephropathy, and that decreased renal function is significantly associated with intrarenal RAS activity in CKD patients with T2DM.

Significant association of poor glycemic control with increased resistance in efferent arterioles--study of inulin and para-aminohippuric acid clearance in humans.

AIMS: To examine whether glomerular hemodynamic parameters in humans are associated with glycemic control indices, by simultaneously measuring clearance of inulin (Cin) and para-aminohippuric acid (CPHA). METHODS: Thirty-one subjects (age 55.4±14.7 years; 15 men and 16 women; 21 diabetics and 10 non-diabetics) were enrolled. Cin and CPAH were measured simultaneously. Afferent arteriolar resistance (Ra), efferent arteriolar resistance (Re), glomerular hydrostatic pressure (Pglo) and glomerular filtration fraction (FF) were calculated according to Gomez' formula. RESULTS: FF correlated significantly and positively with fasting plasma glucose (FPG), hemoglobin A1c (HbA1c) and glycated albumin (GA) (r=0.396, p=0.0303; r=0.587, p=0.0007; r=0.525, p=0.0070, respectively). Pglo correlated significantly and positively with FPG, HbA1c and GA (r=0.572, p=0.0008; r=0.535, p=0.0019; r=0.540, p=0.0053, respectively). Although there was no significant correlation between Ra and glycemic control indices, Re correlated significantly and positively with HbA1c and GA (r=0.499, p=0.0043; r=0.592, p=0.0018, respectively). FF, Pglo and Re were associated significantly with HbA1c and GA after adjustment for age. CONCLUSIONS: These results demonstrate, in humans, that poor glycemic control is associated with increased Re, but not Ra. It is suggested that increased Re causes increased Pglo, leading to increased FF. Thus, hemodynamic abnormalities with poor glycemic control may be related to glomerular hypertension in humans.

Wnt signaling strength regulates normal hematopoiesis and its deregulation is involved in leukemia development.

A strict balance between self-renewal and differentiation of hematopoietic stem cells (HSCs) is required in order to maintain homeostasis, as well as to efficiently respond to injury and infections. Numbers and fate decisions made by progenitors derived from HSC must also be carefully regulated to sustain large-scale production of blood cells. The complex Wnt family of molecules generally is thought to be important to these processes, delivering critical signals to HSC and progenitors as they reside in specialized niches. Wnt proteins have also been extensively studied in connection with malignancies and are causatively involved in the development of several types of leukemias. However, studies with experimental animal models have produced contradictory findings regarding the importance of Wnt signals for normal hematopoiesis and lymphopoiesis. Here, we will argue that dose dependency of signaling via particular Wnt pathways accounts for much, if not all of this controversy. We conclude that there seems little doubt that Wnt proteins are required to sustain normal hematopoiesis, but are likely to be presented in carefully controlled gradients in a tissue-specific manner.

Effect of cinacalcet on bone mineral density of the radius in hemodialysis patients with secondary hyperparathyroidism.

BACKGROUND/AIM: Cinacalcet, an allosteric modulator of the calcium sensing receptor, effectively reduces serum parathyroid hormone (PTH) in patients with secondary hyperparathyroidism. It is not well known whether bone mineral density (BMD) of hemodialysis patients with secondary hyperparathyroidism is altered after cinacalcet treatment. METHODS: The BMD in the distal 1/3 of the radius and in the ultradistal radius, which are enriched with cortical and cancellous bone, respectively, was examined by dual X-ray absorptiometry, 1 year prior to, at the start, and 1 year after cinacalcet treatment, in 61 patients. RESULTS: The BMD of both the distal 1/3 and ultradistal radius decreased significantly in the year prior to cinacalcet treatment (p < 0.01). However, the BMD at either site did not change significantly in the year after cinacalcet treatment. The annual changes in the BMD of the distal 1/3 radius increased significantly from -0.023 ± 0.029 g/cm2/year to -0.002 ± 0.033 g/cm2/year, prior to and after cinacalcet treatment, respectively; however, the annual changes in the BMD of the ultradistal radius did not change significantly prior to and after cinacalcet treatment. CONCLUSION: There was a significant association between cinacalcet treatment and reduction in BMD loss in patients with secondary hyperparathyroidism. Cortical bone, rather than cancellous bone, was particularly affected by cinacalcet treatment.

Monophyletic origin of naked barley inferred from molecular analyses of a marker closely linked to the naked caryopsis gene (nud).

To elucidate the origin of naked barley, molecular variation of the marker sKT7 tightly linked to the nud locus was examined. A total of 259 (53 wild, 106 hulled domesticated, and 100 naked domesticated) barley accessions were studied. Restriction analysis of the sKT7 PCR-amplified product revealed the alleles I, II, III, and IV. All four alleles were found in wild barley, but allele IV was found only in a single accession from southwestern Iran. Hulled domesticated accessions showed alleles I, II, or III, but all naked domesticated accessions had allele IV. The distribution of allele IV in wild barley and its pervasive presence in naked domesticated lines support the conclusion that naked barley has a monophyletic origin, probably in southwestern Iran. The available results suggest two scenarios for the origin of naked barley: either directly from a wild barley with allele IV or from a hulled domesticated line with allele IV that later became extinct. Naked domesticated accessions from different regions of the world have extremely homogeneous DNA sequences at the sKT7 locus, supporting the monophyletic origin of naked barley. For allele IV, four haplotypes (IVb to IVe) were found in 30 naked accessions: IVb was predominant (66.7%) and widely distributed, while the other three haplotypes, differing by only one nucleotide at different positions relative to IVb, showed a localized distribution. The geographical distribution of the haplotypes of sKT7 allele IV suggests migration routes of naked domesticated barley in central and eastern Asia.

Efficient fine mapping of the naked caryopsis gene ( nud) by HEGS (High Efficiency Genome Scanning)/AFLP in barley.

The hulled or naked caryopsis character of barley ( Hordeum vulgare L.) is an important trait for edibility and to follow its domestication process. A single recessive gene, nud, controls the naked caryopsis character, and is located on the long arm of chromosome 7H. To develop a fine map around the nud locus efficiently, the HEGS (High Efficiency Genome Scanning) electrophoresis system was combined with amplified fragment length polymorphism (AFLP). From bulked segregant analysis of 1,894 primer combinations, 12 AFLP fragments were selected as linked markers. For mapping, an F(2 )population of 151 individuals derived from a cross between Kobinkatagi (naked type) and Triumph (hulled type) was used. Seven AFLP markers were localized near the nud region. A fine map was developed with one-order higher resolution than before, along with the seven anchor markers. Among the seven linked AFLP markers (KT1-7), KT1, KT2 and KT6 were co-dominant, and the former two were detected for their single-nucleotide polymorphisms (SNPs) in the same length of fragments after electrophoresis with the non-denaturing gels of HEGS. The nud locus has co-segregated with KT3 and KT7, and was flanked by KT2 and KT4, at the 0.3-cM proximal and the 1.2-cM distal side, respectively. Four of these AFLP markers were converted into sequence-characterized amplified region (SCAR) markers, one of which was a dominant marker co-segregating with the nud gene.

Role of root hairs and lateral roots in silicon uptake by rice.

The rice plant (Oryza sativa L. cv Oochikara) is known to be a Si accumulator, but the mechanism responsible for the high uptake of Si by the roots is not well understood. We investigated the role of root hairs and lateral roots in the Si uptake using two mutants of rice, one defective in the formation of root hairs (RH2) and another in that of lateral roots (RM109). Uptake experiments with nutrient solution during both a short term (up to 12 h) and relatively long term (26 d) showed that there was no significant difference in Si uptake between RH2 and the wild type (WT), whereas the Si uptake of RM109 was much less than that of WT. The number of silica bodies formed on the third leaf in RH2 was similar to that in WT, but the number of silica bodies in RM109 was only 40% of that in WT, when grown in soil amended with Si under flooded conditions. There was also no difference in the shoot Si concentration between WT and RH2 when grown in soil under upland conditions. Using a multi-compartment transport box, the Si uptake at the root tip (0-1 cm, without lateral roots and root hairs) was found to be similar in WT, RH2, and RM109. However, the Si uptake in the mature zone (1-4 cm from root tip) was significantly lower in RM109 than in WT, whereas no difference was found in Si uptake between WT and RH2. All these results clearly indicate that lateral roots contribute to the Si uptake in rice plant, whereas root hairs do not. Analysis of F(2) populations between RM109 and WT showed that Si uptake was correlated with the presence of lateral roots and that the gene controlling formation of lateral roots and Si uptake is a dominant gene.

Age-independent constancy of mineral contents in human vertebra and auditory ossicle.

To elucidate age-related changes of mineral contents in human bones, element contents of human vertebrae and auditory ossicles were determined by inductively coupled plasma atomic-emission spectrometry. The cervical, thoracic, and lumbar vertebrae were removed from 12 vertebral columns. The mallei of auditory ossicle were removed from 27 cadavers. It was found that average relative contents (RCs) of calcium and phosphorus in cervical, thoracic, and lumbar vertebrae remained almost constant within ages ranging from 46 to 99 y. In addition, it was found that the RCs of calcium and phosphorus in men's and women's mallei remained constant within ages ranging from 40 to 98 yr. These results support the view that there is no significant age-dependent change of mineral contents in human bones.

Optimum and sub-optimal temperature effects on stomata and photosynthesis rate of determinate soybeans.

Stomatal frequency, length and width were studied in two determinate type soybean (Glycine max L. Merr.) cultivars at 15, 20 and 25 degrees C on 60th day after emergence. The stomatal frequency on the adaxial leaf surface did not show any consistent trend for the increase of growing temperatures but on the abaxial surface, stomatal frequency significantly decreased for every increase of 5 degrees C. Akishirome had 503, 454 and 379 stomata mm-2 and Akiyoshi had 471, 442 and 384 mm-2 at 15, 20 and 25 degrees C respectively. The stomatal lengths of both surfaces increased toward optimum temperature and were longer in the adaxial surface Maintaining this trend, the lengths varied between 16.3 to 23.4 micrometers on the adaxial surface and from 14.2 to 21.5 micrometers on the abaxial surface. Width of the whole stomatal apparatus at noon time did not show any significant variation due to environmental temperature. Net photosynthesis rate of 4th leaf from top significantly increased in higher temperatures in both cultivars and showed similar trend at 32nd day after emergence and on 62nd day after emergence. Stomatal conductance increased and dark respiration decreased with increasing temperature. Plants grown in 25 degrees C were transferred to 15, 20 and 30 degrees C temperature chambers. On the 30th day after emergence, 4 hours of treatment resulted similar significant effects on net photosynthesis (ranging between 12.55 and 31.37 micromoles CO2 m-2 s-1 in Akishirome, and between 16.26 to 34.53 micrometers CO2 m-2 s-1 in Akiyoshi). 72 hours of similar treatments at 60 day after emergence also produced identical results. Therefore, higher temperature increased stomatal size but decreased its frequency, and increased net photosynthesis and stomatal conductance.

Free radical scavengers suppress the accumulation of platinum in the cerebral cortex.

We investigated whether free radical scavengers and antioxidants inhibit the accumulation of platinum (Pt) in the cerebral cortex. Pt was detected in the cerebral cortex of mice after administration of cisplatin and exposure to short-term hypoxia. When mice were treated with either allopurinol (20 mg/kg) or catalase (100 mg/kg) before cisplatin administration and low oxygen exposure, Pt was not detected in the cerebral cortex. However, Pt was detected in the cerebral cortex of mice pretreated with either a low dosage of allopurinol or heat-denatured catalase. Furthermore, Pt was detected in the cerebral cortex of mice preadministered vitamin C, vitamin E, or deferoxamine. Lipid peroxide levels in the cerebral cortex increased 10 min after the treatment of hypoxia, and peaked 30 min after the treatment. These results suggested that short-term hypoxia produces free radicals, which allows Pt to pass through the blood-brain barrier and accumulate in the cerebral cortex, and that the production of free radicals is reduced by the administration of either allopurinol or catalase, which prevents Pt from passing through the barrier.

Age-dependent aluminum accumulation in the human aorta and cerebral artery.

The purpose of this study was to determine the extent of aluminum (Al) accumulation in the human aorta and cerebral arteries. The Al contents in the aortae and in the cerebral arteries from 23 human subjects was determined by inductively coupled plasma atomic emission spectrophotometry (ICP-AES). The subjects' age range was 45-99-yr-old; 15 of the subjects were males and 8 were females. Al was detected in twelve aortae and in six cerebral arteries, when the entire specimen was analyzed. Two specimens where Al was found in the cerebral arteries contained no Al in the aorta. No relationship to the subject's sex was found. When related to age, two groups were established. Group L (45-75 yr old) and group H (> 75 yr old), which exhibited aortal Al concentrations of 33.3 and 72.7%, respectively. When the aortic wall was dissected into the tunica intima, media, and adventitia, Al was found mainly in the tunica media. In the aorta, significant relationships were found between Al and phosphorus (P) levels (r = 0.801, p < 0.01) and between Al and calcium (Ca) (r = 0.661, p < 0.05). We have concluded that Al accumulation is age-dependent and that it occurs both in the aorta and in the cerebral artery. In the aorta, accumulation occurs mainly in the tunica media. Both P and Ca appear to enhance aortal Al accumulation.

Age-related change of mineral content in the human thoracic aorta and in the human cerebral artery.

The relative contents (RCs) of mineral elements in aortae and cerebral arteries from 23 subjects, with ages ranging between 45 and 99 yr, were analyzed by inductively coupled plasma atomic emission spectrometry. The RCs of calcium, phosphorus, and magnesium in the aortae increased markedly after the age of 70. While the RC of sulfur in aortae decreased gradually after that age. It was found that accumulation of calcium and phosphorus occurred primarily in the tunica media of aorta, and secondarily in the tunica intima. Furthermore, the RCs of calcium, phosphorus, and magnesium in cerebral arteries increased markedly after the age of 70, whereas the RC of sulfur in cerebral arteries decreased after age 70. It was found that accumulation of calcium and phosphorus in the cerebral arteries were 30 and 60%, respectively, lower than those in the aortae with ages ranging between 45 and 99 yr.

Detection of platinum in the brain of mice treated with cisplatin and subjected to short-term hypoxia.

Cisplatin is widely used for cancer treatment but has strong side-effects, including nephrotoxicity. Neurotoxicity has been thought to be limited to peripheral damage because the blood-brain barrier is thought to be impervious to hydrophilic substances such as cisplatin. Because anoxic ischaemia has been associated with lesions of the barrier, inductively coupled plasma mass spectrometry has been used to monitor the accumulation of platinum in the brains of mice treated with cisplatin and exposed to oxygen-deficient atmospheres. Platinum was detected in the cerebral cortex of mice 24 h after the administration of cisplatin (3 mg kg-1) followed by exposure for 60 s to an atmosphere containing 7% oxygen, but not in the cerebral cortex of mice exposed to normal atmospheres. Platinum was also observed in the cerebral cortex after exposure for 120 s to an atmosphere containing 14% oxygen, and platinum levels increased as the concentration of oxygen was reduced. The highest platinum levels were obtained 10 h after administration of cisplatin and exposure for 120 s to an atmosphere containing 7% oxygen. Platinum was still retained in the cerebral cortex one week after administration. In contrast, platinum levels in the blood and kidney decreased with time. Platinum levels were measured in seven regions of the brain: the right and left cerebral cortices, the basal ganglia, the thalamus and hypothalamus, the bulbus olfactorius, the cerebellum, and the mesencephalon. When cisplatin was administered to mice not subjected to hypoxia, platinum was not detected in the right and left cerebral cortices, basal ganglia or the thalamus and hypothalamus, but was detected in the bulbus olfactorius, cerebellum and mesencephalon. When such mice were exposed to low levels of oxygen, however, platinum was detected in the right and left cerebral cortices, the basal ganglia and the thalamus and hypothalamus. Platinum levels in the cerebellum and mesencephalon of mice exposed to low levels of oxygen were higher than those of mice exposed to normal air. In addition, platinum levels in the bulbus olfactorius were significantly higher than those in the other regions, although the platinum content of the bulbus olfactorius was not affected by hypoxia. From these observations, it is concluded that platinum is easily accumulated in the bulbus olfactorius after the administration of cisplatin, and that after exposure to atmospheres containing low levels of oxygen, platinum easily passes through the blood-brain barrier and accumulates in all parts of the brain.

Difference of mineral contents in human intervertebral disks and its age-related change.

To establish a difference of the relative contents (RCs) of elements among the cervical, thoracic, and lumbar intervertebral disks and its age-related change, the intervertebral disks between the axis and the sacrum, which were resected from the nine cadavers who died at 53 to 99 yr old, were analyzed by inductively coupled atomic plasma emission spectrometry. It was found that both the RCs of calcium and phosphorus were high in the cervical disks, especially the highest in the disk between the 6th and 7th cervical vertebrae, and lower in the order of the cervical, thoracic, and lumbar intervertebral disks. In regard to the RCs of sulfur and magnesium, there were no significant differences among the cervical, thoracic, and lumbar intervertebral disks. In addition, it was found that both the RCs of calcium and phosphorus in the cervical intervertebral disks started to increase in the sixth decade of life, became the highest in the eighth decade of life, and then decreased.

An improved method for estimating original mineral contents in excavated bone using sulfur.

Trace element analysis in excavated bones is complicated by the lack of a reliable index for estimating the original amount of bone material. In this study, we subjected modern human bones to alkali treatment to simulate aging. Alkali treatment of vertebrae with attached muscle did not affect sulfur (S) content; it increased the magnesium (Mg), phosphorus (P), and zinc (Zn) contents, and tended to decrease iron (Fe) content of the bones. When vertebrae cleaned of muscle were used, alkali treatment did not affect S and Fe contents but increased Mg, P, Ca, and Zn contents. Ca and S contents were higher in excavated bones (200-1300 yr old) than in their surrounding soils. In contrast, S, Mg, and Ca contents per dry weight did not differ between the excavated bones and the alkali-treated modern bones. These results indicate that S can provide a more accurate index of excavated bones than the often-used Ca content or dry wt measures, especially for bones excavated from calcium-rich soils.

Cooperative clinical trial of photodynamic therapy with photofrin II and excimer dye laser for early gastric cancer.

BACKGROUND AND OBJECTIVE: Photodynamic therapy (PDT) is a recently developed endoscopic method for treating malignant tumors. For obtaining more photodynamic action with less thermal effect, we employed as the excitation light source for PDT an excimer dye laser, which is a pulsed laser with extremely high peak power, instead of an argon dye laser, which is a continuous wave laser and has been used conventionally. STUDY DESIGN/MATERIALS AND METHODS: The effect of PDT using Photofrin II and the excimer dye laser was evaluated in 27 patients with early gastric cancer. RESULTS: Complete responses (CR) were obtained in 88% of 24 assessable patients and the response rate was 100%. CR was observed in all cases of lesions of superficial depressed type without ulceration and/or with tumor diameter less than 2 cm. Regarding toxicity, mild cutaneous reaction and photosensitivity were seen and lasted several weeks. There were no serious abnormalities in laboratory tests. CONCLUSION: We conclude that PDT is a promising modality for early gastric cancer.

Renal changes of streptozotocin-induced diabetic rats fed a low-zinc diet.

The changes in kidneys of streptozotocin (STZ)-induced diabetic rats fed a low-zinc (LZ) diet were observed. Calcium deposits were detected in the LZ-diabetic groups from the 2nd to the 8th week. The deposits were mainly detected in the corticomedullary junction, and found in the tubular lumina and epithelial cytoplasm and interstitium. Tubular morphological changes, including luminary distension, epithelial flattening, and paleness of cytoplasm and nuclei, were observed near the calcium deposits in the LZ-diabetic group over the 2nd week. Moreover, at the 8th week, wedge-shaped vasogenic lesions were found on the surface of the renal cortex in the LZ-diabetic group. No changes were detected in the control for the LZ or in the diabetic group fed a standard (SC) diet. When STZ was administered, plasma glucose level in groups fed LZ or SC diet increased in the 1st week, and over the 2nd week, glucose level was maintained at more than 400 mg/dL. Glucose level of the LZ-diabetic group did not differ from that of the SC-diabetic group. However, urinary N-acetyl-beta-D-glucosaminidase activity of the LZ-diabetic group at the 8th week was significantly higher than that of the SC-diabetic group. These findings suggested that low-zinc diet hastens renal damages in diabetic rats.

Comparison of three different methods for measurement of tissue platinum level.

We attempted to make a comparison of three methods for tissue platinum; atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and inductively coupled plasma mass spectrometry (ICP-MS). The determination limits were 0.05 ng/mL on ICP-MS, 50 ng/mL on ICP-AES, and 200 ng/mL on AAS, and the recovery rates were 97.7 +/- 6.9% on ICP-MS, 69.0 +/- 3.0% on ICP-AES, and 102.4 +/- 4.0% on AAS, respectively. Platinum was detected by ICP-AES and ICP-MS in human vertebrae, but the level was higher by ICP-AES than by ICP-MS. In the mouse kidney treated with cisplatin, platinum was detected by ICP-MS, but not by ICP-AES. As cadmium gives the absorption peak close to platinum, cadmium was measured together with platinum by ICP-AES in the vertebrae. From these, ICP-MS is the most sensitive for measurement at tissue platinum. The sensitivity of ICP-AES looks worse for measuring the tissue platinum, and it is necessary to take care of the contaminant of metals, especially cadmium. AAS is not suitable for measurement of tissue platinum as in the vertebrae and kidneys, because platinum was not detectable by AAS.

Accumulation of mercury in excavated bones of two natives in Japan.

Mercury content of excavated bones and surrounding soil was compared between the two areas of Shikoku, Tokushima and Matsuyama. Results show a high variance of mercury content between localities and between ages of the burials. There was a high mercury occurrence in the 6-7th century in Tokushima and a moderate one in Matsuyama, and a trace in the 12-17th century in both places. Moreover, a low level of mercury was observed in the soil samples of Tokushima, and mercury was not detected in any of the Matsuyama soil samples. Therefore, these occasions of high mercury content may be due to artificial uptake, and may relate to differences in conventions and customs.