Prediction of heading date, culm length, and biomass from canopy-height-related parameters derived from time-series UAV observations of rice.

Unmanned aerial vehicles (UAVs) are powerful tools for monitoring crops for high-throughput phenotyping. Time-series aerial photography of fields can record the whole process of crop growth. Canopy height (CH), which is vertical plant growth, has been used as an indicator for the evaluation of lodging tolerance and the prediction of biomass and yield. However, there have been few attempts to use UAV-derived time-series CH data for field testing of crop lines. Here we provide a novel framework for trait prediction using CH data in rice. We generated UAV-based digital surface models of crops to extract CH data of 30 Japanese rice cultivars in 2019, 2020, and 2021. CH-related parameters were calculated in a non-linear time-series model as an S-shaped plant growth curve. The maximum saturation CH value was the most important predictor for culm length. The time point at the maximum CH contributed to the prediction of days to heading, and was able to predict stem and leaf weight and aboveground weight, possibly reflecting the association of biomass with duration of vegetative growth. These results indicate that the CH-related parameters acquired by UAV can be useful as predictors of traits typically measured by hand.

Separation Effect and Development of Implantation Technique of Hydrogel Spacer for Prostate Cancers.

PURPOSE: The purpose of this study is to improve the placement of a hydrogel spacer in patients with prostate cancer receiving radiation therapy. METHODS AND MATERIALS: A total of 160 patients with prostate cancer were classified into 3 groups: No spacer (group 1; n = 30), spacer placed using conventional technique (group 2; n = 100), and spacer placed using new technique (group 3; n = 30). When placing the spacer, the tip of the needle is placed at the middle of the prostate gland (group 2), or at a level corresponding to a cranial:caudal ratio of 6:4 and as close to the prostate gland as possible (group 3). The separation effect was examined and compared among the groups. RESULTS: The separation in group 2 was larger than that in group 1 from the base to the apex level of the prostate (4 mm), but the separation in group 3 was larger than that in group 2 from the middle to the apex level of the prostate (4 mm). The separation values for the middle to the apex, the spacer thickness from the apex level to the apex (10 mm), the rectal exclusion from the middle to the apex, and the laterality were correlated with the 50 and 60 Gy relative biologic effectiveness (Gy[RBE]) rectal dose (P = 4.1 × 10-9 - .046). The separation vales were strongly correlated with the spacer thickness at the apex (10 mm) and the apex (4 mm; P = 1.1 × 10-18 - 1.8 × 10-17). The rectal volumes at 10 to 60 Gy(RBE) differed among the groups (P = 5.1 × 10-19 - 5.4 × 10-3). The rectal volumes in group 2 were smaller than those in group 1 at all dose levels, but those in group 3 were smaller than those in group 2 at dose levels of 30 to 50 Gy(RBE). CONCLUSIONS: The separation, spacer thickness, and rectal exclusion from the middle to the apex of the prostate and the laterality of the hydrogel spacer affected the reduction in the rectal dose. The rectal dose can be further reduced by implanting a spacer on the caudal and prostate side.

Anthocyanin and proanthocyanidin contents, antioxidant activity, and in situ degradability of black and red rice grains.

OBJECTIVE: An experiment was conducted to assess the antioxidant contents and activities of colored rice grains and to evaluate their nutritive characteristics in terms of chemical composition and in situ ruminal degradation. METHODS: Ten cultivars of colored rice grains (Oryza sativa L.) collected from several areas of Japan were studied, and control rice without pigment, maize, barley, and wheat grains were used as control grains. Their chemical compositions, pigment, polyphenol contents, total antioxidant capacity (TAC), and degradation characteristics were determined. RESULTS: The starch contents of the colored rice grains were in the range of 73.5% to 79.6%, similar to that of the control rice grain. The black and red rice grains contained anthocyanin (maximum: 5,045.6 µg/g) and proanthocyanidin (maximum: 3,060.6 µg/g) at high concentrations as their principal pigments, respectively. There were significantly (p<0.05) positive relationships among the pigment contents, polyphenol content, and TAC values in the colored and control rice grains, indicating that the increase in pigment contents also contributed to the increased polyphenol content and TAC values in the colored rice grains. The dry matter and starch degradation characteristics, as represented by c (fractional degradation rate of slowly degradable fraction) and by the effective degradability, of the colored rice grains and the control rice grain were ranked as follows among commonly used grains: wheat>barley ≥rice>maize. The colored rice grains also included the most-digestible starch, since their potential degradable fraction and actual degradability at 48 h incubation were almost 100%. CONCLUSION: Colored rice grains have high potential to be used as antioxidant sources in addition to starch sources in ruminants.

Improved Lower Urinary Tract Symptoms Associated With Testosterone Replacement Therapy in Japanese Men With Late-Onset Hypogonadism.

This study aimed to investigate the effects of testosterone replacement therapy (TRT) on lower urinary tract symptoms (LUTS) in men with late-onset hypogonadism (LOH) and to identify parameters predicting the efficacy of TRT in improving LUTS. This study included 60 consecutive Japanese men who were diagnosed with LOH and subsequently received TRT between January 2009 and December 2014. In this series, 250 mg of testosterone was injected intramuscularly every 3 or 4 weeks in all patients. The following parameters were retrospectively reviewed: body mass index (BMI), Aging Male Symptom (AMS) score, International Prostate Symptom Score (IPSS), International Index of Erectile Function-5 (IIEF-5) score, residual urine volume, prostate volume, serum levels of the prostate-specific antigen (PSA), and total- and free-testosterone levels before and 6 months after TRT. No significant differences were observed in BMI, residual urine volume, or prostate volume between surveys before and after TRT. The AMS score, IPSS, and IIEF-5 score were significantly improved and significant increases were noted in the serum levels of PSA and total- and free-testosterone levels after TRT. An analysis of IPSS subscores documented the significant improvement in storage symptom scores, but not in voiding symptom scores after TRT. Multivariate analyses of parameters assessed in this study identified the pretreatment AMS score, posttreatment IIEF-5 score, and prostate volume as independent predictors of improvements in IPSS following TRT. This study revealed that TRT appeared to have considerable therapeutic effects on LUTS, particularly on storage symptoms, in men with LOH.

Quantitative trait loci analysis of grain appearance in Oryza sativa L. 'Emi-no-kizuna'.

A quantitative trait locus (QTL) analysis was conducted on grain appearance in Emi-no-kizuna, a rice cultivar that has superior and stable appearance of the brown rice grain and high tolerance to high temperature stress, by using F3 lines derived from Emi-no-kizuna and Tomohonami. The investigation was performed 2013 and 2015. In summer 2013 the air temperature was higher and the larger differences in grain appearance were observed. In the QTL analysis, a highly contributing locus, qGA8, was detected at the end of the short arm of chromosome 8. Because trends of reduced the occurrence of white immature kernel and increased the percentage of perfect grain were observed in Emi-no-kizuna genotype in both years, qGA8 is likely to be an important QTL that is dominant in the superior grain appearance of Emi-no-kizuna. Also, qGA8 was linked to a QTL associated with days to heading. Another QTL, qGA7, associated with grain appearance was detected on chromosome 7 in 2013. Because no negative correlation was found between the genotype of qGA8 and thousand grain weight, it should be possible to breed cultivars that possess Emi-no-kizuna genotype qGA8 without a decrease in thousand grain weight.

Improvement of seed shattering and dormancy in Oryza sativa L. 'Hokuriku 193' based on genetic information.

In this study, we investigated the genetic basis of seed shattering and dormancy in Hokuriku 193 and bred an NIL improved these traits. Analysis of an F3 population from Hokuriku 193 × Koshihikari revealed a general correspondence between seed shattering and genotypes at the qSH1 locus, suggesting a strong influence of this locus on the seed shattering in Hokuriku 193. An F2 population from [ms-bo] Nekken 2 × Hokuriku 193 was also analyzed to identify quantitative trait loci (QTLs) for seed dormancy as measured by germination rate in the first December and March after seed harvest. The results revealed a concurrence QTLs of on chromosomes 1, 3, and 6 (qSDo1, qSDo3, qSDo6). In particular, qSDo1 and qSDo6 were considered regions worthy of active modification because they were QTL regions that promoted seed dormancy when carrying Hokuriku 193 genome regions around. SSDo_NIL, a near isogenic line (NIL) derived from Hokuriku 193 by introgressing Nekken 2 alleles only at the qSH1 locus and qSDo1, did not shatter, and its germination rate was significantly higher than that of Hokuriku 193. Yield performance was similar between SSDo_NIL and Hokuriku 193, suggesting that improvement of seed shattering and dormancy does not affect yield.

Quantitative trait loci analysis of blast resistance in Oryza sativa L. 'Hokuriku 193'.

To investigate the genetic background responsible for blast resistance in Oryza sativa L. 'Hokuriku 193', QTL analysis was conducted using the F3 lines from the cross [ms-bo] Nekken 2 × Hokuriku 193 that were artificially infected with rice blast fungus (Magnaporthe grisea). QTLs were detected on chromosomes 1, 4, 6 and 12 that correlated with greater blast resistance in the Hokuriku 193-type lines. Notably, the QTL on chromosome 12 had a major effect and localized to the same region where Pi20(t), a broad-spectrum blast resistance gene, is positioned, suggesting strongly that the blast resistance of Hokuriku 193 was controlled by Pi20(t). Also, QTL analysis of the lines found to have no Pi20(t) detected two QTLs on chromosome 4 (qBR4-1 and qBR4-2) and one QTL on chromosome 6 (qBR6), of which qBR4-2 and qBR6 correlated with higher percentages of resistant plants in the Hokuriku 193-type lines. The blast susceptibility of BR_NIL (a NIL of Hokuriku 193 from which Pi20(t) was eliminated) was greater than that of Hokuriku 193, suggesting that elimination of Pi20(t) may markedly increase blast susceptibility. The disease severity of BR_NIL was mild, which might be the effect of qBR4-2 and/or qBR6.

[Hypertension with chronic kidney disease: anti-hypertensive therapy recommended for the management of hypertension with CKD in JSN-CKD GL 2013 and JSH2014].

For clinical practice guidelines for the management of hypertension with CKD, the Japanese Society of Nephrology (JSN) and the Japanese Society of Hypertension (JSH) evaluated recently published evidence in corporation with each other. After considerable and careful discussion, both JSN and JSH revised their respective guidelines [the Evidence-based Clinical Practice Guideline for CKD 2013 (JSN-CKD GL 2013) and JSH2014]. This section will mainly introduce anti-hypertensive therapy recommended for the management of hypertension with CKD in both guidelines. Recommendation statements for the Management of Hypertension with CKD are as follows: 1) Anti-hypertensive therapy in CKD is strongly recommended to inhibit or prevent the progression of renal dysfunction and to prevent the occurrence or recurrence of CVD by reducing blood pressure (BP) (Grade A). 2) In all diabetic CKD, the target level of clinic BP is recommended as < 130/80 mmHg, irrespective of the presence or absence of albuminuria/proteinuria (Grade B). 3) In all non-diabetic CKD, the target level of clinic BP is strongly recommended as consistently < 140/90 mmHg, irrespective of the presence or absence of albuminuria/proteinuria (Grade A). 4) In non-diabetic CKD with A2 and A3 categories, the target level of clinic BP can be set as < 130/80 mmHg (Grade C1). 5) In diabetic CKD with A1 category, ARBs and ACE inhibitors are suggested as first-line anti-hypertensive drugs(Grade C1). 6) In diabetic CKD with A2 and A3 categories, ARBs and ACE inhibitors are recommended as first-line anti-hypertensive drugs (Grade A). 7) In non-diabetic CKD with A1 category, ARBs, ACE inhibitors, calcium channel blockers (CCBs) and diuretics are recommended as first-line anti-hypertensive drugs (Grade B). 8) In non-diabetic CKD with A2 and A3 categories, ARBs and ACE inhibitors are recommended as first-line anti-hypertensive drugs (Grade B).

Assessment of Time-dependent Changes in Semen Parameters in Infertile Men After Microsurgical Varicocelectomy.

OBJECTIVE: To characterize the changes in seminogram findings in infertile men after varicocelectomy. METHODS: This study included 71 consecutive infertile men who underwent microsurgical low ligation varicocelectomy and received 3 semen analyses, 1 before microsurgical varicocelectomy and again at 3 and 12 months after. Total motile sperm count (TMSC) was calculated using the following formula: [volume (mL) × concentration (millions/mL) × motility (%)]. RESULTS: Despite the lack of significant changes in the proportion of sperm with abnormal morphology, sperm concentration, motility, and TMSC in the 71 patients were significantly higher at 3 and 12 months after varicocelectomy than before surgery. However, no further improvement in these parameters at 12 months after varicocelectomy was noted compared with those at 3 months. Furthermore, when the included men were divided into 3 groups according to preoperative TMSC as <3 million, 3-9 million, and >9 million, TMSCs at 3 months after varicocelectomy in all 3 groups were significantly higher than those before varicocelectomy; however, TMSCs at 12 months after surgery in all groups were similar to those at 3 months. CONCLUSION: The level of improvement in semen parameters at 3 months after varicocelectomy may be stable at 12 months after surgery, irrespective of baseline values of TMSC. Therefore, varicocelectomy could be offered as a therapeutic option for infertile men, even for couples with an older woman, because its efficacy is evaluable at 3 months after surgery, and assisted reproductive technology could be immediately applied to ineffective cases.

Efficient transfection of DNA into primarily cultured rat sertoli cells by electroporation.

The expression of exogenous DNA in Sertoli cells is essential for studying its functional genomics, pathway analysis, and medical applications. Electroporation is a valuable tool for nucleic acid delivery, even in primarily cultured cells, which are considered difficult to transfect. In this study, we developed an optimized protocol for electroporation-based transfection of Sertoli cells and compared its efficiency with conventional lipofection. Sertoli cells were transfected with pCMV-GFP plasmid by square-wave electroporation under different conditions. After transfection of plasmid into Sertoli cells, enhanced green fluorescent protein (EGFP) expression could be easily detected by fluorescent microscopy, and cell survival was evaluated by dye exclusion assay using Trypan blue. In terms of both cell survival and the percentage expressing EGFP, 250 V was determined to produce the greatest number of transiently transfected cells. Keeping the voltage constant (250 V), relatively high cell survival (76.5% ± 3.4%) and transfection efficiency (30.6% ± 5.6%) were observed with a pulse length of 20 µm. The number of pulses significantly affected cell survival and EGFP expression (P < 0.001). Cell survival clearly decreased following one to three pulses, from 83.9% ± 6.1% to 3.2% ± 1.1%, with EGFP expression increasing from 41.8% ± 9.4% to 66.7% ± 5.2%. The yield of positive cells increased with increasing concentration of plasmid DNA (range, 10-50 µg/ml), from 14.0% ± 2.8% to 35.0% ± 6.3%, but cell viability steadily decreased following 20 µg/ml plasmid DNA, from 73.1% ± 4.9% to 57.0% ± 6.6%. Compared with two popular cationic lipid transfection methods, the transfection efficiency of electroporation (21.5% ± 5.7%) was significantly higher than those of Lipofectamine 2000 (2.9% ± 1.0%) and Effectene (1.9% ± 0.8%) in this experiment (P < 0.001). We describe the process of optimizing electroporation conditions, and the successful electroporation of plasmid DNA into primarily cultured Sertoli cells. Our results indicate that the method of electroporation is more suitable than other approaches for the transfection of Sertoli cells.

Significant improvement of sperm DNA quality after microsurgical repair of varicocele.

Varicocele is currently the most common irregularity identified in males that is associated with impaired spermatogenesis. It primarily presents in the form of decreased sperm count and motility, abnormal morphology, and significantly increased sperm DNA fragmentation. Several studies have shown that surgical repair improves semen parameters and increases the odds of spontaneous pregnancy. However the exact effect of surgical repair treatment remains controversial. Therefore, the aim of our study was to evaluate the effectiveness of microsurgical repair by comparing common semen parameters and sperm DNA fragmentation index (DFI). We evaluated infertile men (n = 19) who underwent microsurgical subinguinal varicocelectomy for treatment of clinical varicocele before and 3 months after surgery. Normozoospermic men (n = 19) were considered as the normal control group. Semen parameters improved significantly after surgery when compared with that before surgery, but still significant differences with the normal control group were observed. In comparison, sperm DNA integrity improved significantly after surgery (percentage DFI decreased from 28.4 ± 15.6% before surgery to 22.4 ± 12.9%, at 3 months post surgery) to similar levels as the normal control group. These results suggest that microsurgical repair may be considered as a treatment option in infertile men with palpable varicocele.

Effect of varicocelectomy on testicular volume in children and adolescents: a meta-analysis.

OBJECTIVE: To evaluate the effect of surgical intervention on catch-up growth as determined by a decreased testicular volume discrepancy in children and adolescents with varicocele. METHODS: A systematic search was performed using MEDLINE and the PubMed database and cross-referenced as of October 28, 2011 using the terms "varicocele," "children," "adolescent," "surgery," and "testicular volume." All relevant studies were of the testicular volume discrepancy variance before and after surgical repair. The outcomes included the number of patients with initial testicular atrophy and those with catch-up growth after surgical repair. The database search, quality evaluation, and data extraction were independently performed by 2 reviewers. RESULTS: Of 75 studies, 14 were included for analysis and involved 1475 patients. The combined analysis showed that the testicular volume discrepancy was significantly reduced after surgery in the ≥10% group (P < .00001) and ≥20% group (P < .00001), respectively. No difference was found between the 2 groups (P = .70). Taken together, the number of patient with testicular volume disproportion in all pediatric and adolescent varicocele patients significantly decreased after surgery (P < .00001). The average proportion of catch-up growth was 76.4% (range 52.6%-93.8%). CONCLUSION: The meta-analysis suggested clear advantages of surgical intervention on reducing testicular hypotrophy when the discrepancy is ≥10% in children and adolescents with varicocele. Additional prospective and controlled studies are warranted to elucidate the treatment of children and adolescents with varicocele.

Effect of surgical repair on testosterone production in infertile men with varicocele: a meta-analysis.

OBJECTIVES: To determine the effect of surgical varicocele repair in improving testicular Leydig cell function as shown by increased testosterone production. METHODS: Eligible studies were searched in Medline and the Pubmed database, and cross-referenced as of 31 May 2011 using the terms "varicocele,""testosterone" and "surgery." The database search, quality assessment and data extraction were independently carried out by two reviewers. Only studies including patients with testosterone evaluation before and after surgery were considered for the analysis. A systematic review and meta-analysis was carried out for continues variables using random effect models. RESULTS: Out of 125 studies, a total of nine were selected, including 814 patients. The combined analysis showed that mean serum testosterone levels after surgical treatment increased by 97.48 ng/dL (95% confidence interval 43.73-151.22, P=0.0004) compared with preoperative levels. CONCLUSIONS: Surgical treatment of varicocele significantly increases testosterone production and improves testicular Leydig cell function.

Inflammatory pseudotumor of the retroperitoneum removed via a retroperitoneoscopic approach.

BACKGROUND: Inflammatory pseudotumors were mostly encountered in the lung. Retroperitoneal inflammatory pseudotumors are relatively rare. Although laparoscopic surgery with a modified flank position is widely performed for retroperitoneal tumors, we placed the patient in the supine position to maintain the normal anatomical view of the retroperitoneal space. We report a case of retroperitoneal inflammatory pseudotumor extracted via retroperitoneoscopic surgery in the supine position. METHODS AND RESULTS: A 53-year-old man presented with back pain and frequent urination. Ultrasonographic examination revealed a solid tumor above the urinary bladder. This tumor was diagnosed as a primary retroperitoneal tumor by computed tomography, magnetic resonance imaging, and angiography. The retroperitoneoscopic procedure was adopted to remove this tumor. Histopathologic examination revealed an inflammatory pseudotumor. There was no evidence of recurrence 5 years after surgery. CONCLUSIONS: The diagnosis of the inflammatory pseudotumor is rarely made before histologic examination. Only pathologic examination allows the correct diagnosis. Consequently, most patients undergo surgical treatment. A recurrence rate of 25% has been reported for inflammatory pseudotumors. Thus, radical resection is needed. The retroperitoneal laparoscopic approach with the patient in the supine position is useful for surgically treating these primary retroperitoneal tumors located below the level of the renal vessels.

Laparoscopic adrenalectomy: troublesome cases.

Among 143 cases of laparoscopic adrenalectomy carried out from 1993 to the present, 13 patients in whom the surgical manipulation presented problems were examined. Problems occurred due to the condition of the adrenal tumors themselves in six patients, whereas problems occurred due to the operative history in four patients. There were three patients with no operative history but with strong intraperitoneal adhesion. In patients with a history of laparotomy in other fields such as open cholecystectomy, gastrectomy or colostomy, operations were possible in most patients by examining the trocar site preoperatively. Patients with strong adhesion even without a history of surgery could be handled by full separation of the adhesion during surgery. In patients with bleeding in the adrenal tumors, large adrenal tumors, or tumors impacted in the liver, methods such as changing the sequence of separation procedures were required. In patients with a history of renal subcapsular hematomas due to extracorporeal shock wave lithotripsy (ESWL), it was not possible to understand the conditions of adrenal or perinephritic adhesion in preoperative imaging diagnosis, but resection was possible by changing the order of separation procedures and by using optimal instruments and devices. As with any surgery, including open surgeries, it is necessary to obtain knowledge on how to deal with variations in laparoscopic adrenalectomy to assure safe outcomes and to always consider effective methods for coping with unexpected difficulties.

Evaluation of renal function and proteinuria based on mass health examinations in young Japanese obese adults.

BACKGROUND: Although obesity is recognized to be a risk factor for chronic kidney disease (CKD), few studies have reported the association between obesity and CKD in the young population. We investigated the relationship between obesity and renal function including proteinuria in young Japanese. METHODS: This cross-sectional study consisted of 16,031 men and 5,746 women aged from 20 to 39 years who received health examinations. The subjects were stratified into four age groups (20-24, 25-29, 30-34, and 35-39 years) or into four groups based on the number of risk factors (hypertension, hyperglycemia, dyslipidemia, and hyperuricemia). The relationship between obesity and risk factors and the relationship between obesity and estimated glomerular filtration rate (eGFR) were analyzed. RESULTS: There were no significant differences in eGFR between obese and nonobese groups, except in the male 35-39 years age group. Body mass index (BMI) in both men and women increased with increase in number of risk factors (P < 0.001). Multivariate analysis revealed that hypertension, hyperglycemia, dyslipidemia, and hyperuricemia were independently associated with obesity. Obesity and the risk factors were independently associated with proteinuria. CONCLUSION: The present study indicated that obesity was an independent risk factor for proteinuria in healthy subjects younger than 40 years of age. The other risk factors were independently associated with obesity. These findings suggest that obesity causes proteinuria concomitantly with other risk factors such as hypertension, diabetes, and dyslipidemia in young adults.

Expression of cyclooxygenase-2 in the juxtaglomerular apparatus of angiotensinogen gene-knockout mice.

AIMS: The present study was designed to examine the role of the renin-angiotensin system in the regulation of macula densa cyclooxygenase-2 (COX-2) during altered dietary salt intake. METHODS: We investigated COX-2 expression in the macula densa of angiotensinogen gene-knockout (Atg-/-) mice. COX-2 expression in the renal cortex was determined by real-time quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: The renal cortical expression of COX-2 mRNA increased 24.7 times in Atg-/- mice compared with Atg+/+ mice. When Atg-/- mice were fed a high-salt diet (4% NaCl) for 10 days, the levels of COX-2 expression were markedly suppressed. The macula densa COX-2 immunoreactivity was correlated with the mRNA expression. The selective inhibition of neuronal isoform of nitric oxide synthase (N-NOS) activity by 7-nitroindazole significantly reduced the levels of COX-2 mRNA in Atg-/- mice by 54.1%. CONCLUSION: These results suggest that (1) COX-2 activity in the macula densa can be regulated by salt intake through a mechanism independent of the renin-angiotensin system, and (2) COX-2 expression is functionally linked to renal cortical N-NOS activity in Atg-/- mice.

Analysis of factors that affect short-term blood pressure variability in patients with chronic renal failure.

Recent reports suggest the relationship of short-term blood pressure (BP) variability to cardiovascular target organ damage. In this study, short-term BP variability was assessed as the standard deviation of daytime and nighttime BP in 36 hospitalized patients with chronic renal failure (CRF) who underwent ambulatory BP monitoring. Positive correlations were observed between body mass index (BMI) and daytime systolic and diastolic BP variability, BMI and nighttime diastolic BP variability, cholesterol and daytime systolic BP variability, cholesterol and nighttime systolic and diastolic BP variability, nocturnal decline in BP and nighttime diastolic BP variability, and plasma concentration of norepinephrine (p-NE) and nighttime systolic BP variability. In multivariate linear regression analyses, BMI showed the strongest association with daytime and nighttime diastolic BP variability (p < .005 and p < .05). On the other hand, cholesterol and p-NE were the primary determinants of daytime and nighttime systolic BP variability, respectively (p < .01 and p < .0005). Interestingly, CRF patients with ischemic heart disease (IHD) had significantly increased daytime systolic and diastolic BP variability and nighttime systolic BP variability (p < .05 or less). Furthermore, logistic regression analysis demonstrated that nighttime systolic BP variability was an independent risk factor of IHD in patients with CRF (odds ratio 1.50 [95% confidence interval 1.01 to 2.25]; p < .05). Taken together, short-term BP variability is suggested to be affected by BMI, cholesterol, and p-NE in CRF patients. Furthermore, sympathetic nerve overactivity may be involved in cardiovascular complications in CRF patients through the increase in nighttime systolic BP variability.

Implication of base heart rate in autonomic nervous function, blood pressure and health-related QOL.

Increased resting heart rate (HR) and increased sympathetic nervous activity are independent risk factors for cardiovascular disease. Recently, base heart rate (HRo: minimum stable HR during sleep) has been reported to relate to cardiac stroke volume and age. However, little is known about the relevance of HRo. The aim of our study was to evaluate how HRo is associated with HR variability (HRV), blood pressure and health-related quality of life (HRQOL) in healthy subjects. A total of 139 volunteers participated in this study that measured 24-hr HR, HRV, and blood pressure. HRo was estimated from the trendgram and the histogram of HR during the nighttime (sleep) period, and calculated as the 1% lowest value of its integral. HRQOL was assessed by Medical Outcome Study Short-Forum 36-Item Health Survey. Sympathetic nervous activity (ratio of low frequency to high frequency component: LF/HF) and parasympathetic nervous activity (high frequency component: HF) were calculated by ECG monitoring. HRo was positively correlated with 24-hr LF/HF and nighttime LF/HF. HRo was negatively correlated with 24-hr HF and nighttime HF. Moreover, HRo was positively correlated with the scores of social functioning and role-physical. Using multivariate analysis, HRo is related to LF/HF, body mass index, and the score of social functioning (HRQOL). HRo may be a useful indicator for assessing sympathetic nervous activity and HRQOL in normotensive healthy subjects.