[Rupture of Artificial Blood Vessel by a Sternal Wire:Report of a Case].

Formation of a pseudoaneurysm due to blood leakage from the anastomotic site of the vascular graft in large-diameter vessels is often seen, but formation of a pseudoaneurysm from the non-anastomotic site is extremely rare. A 68-year-old woman presented with a history of double valve replacement for combined valvular disease at 37 years old and hemiarch replacement for thoracic aortic dilatation at 65 years old. She visited the emergency room with a 2-week history of chest pain. Contrast-enhanced computed tomography (CT) revealed a 5-cm-diameter pseudoaneurysm and extravasation from the ascending aorta, so emergency surgery was performed. Around the ascending aorta area, we confirmed bleeding from a 5-mm dehiscence in the non-anastomotic part of the graft prosthesis, so hemostasis was performed with a cross-stitch mattress suture over a felt strip. Initially, the cause of the pseudoaneurysm was unknown, but re-examination of CT images from after the previous hemiarch replacement confirmed contact between the sternal wire and graft prosthesis. The wire was thus considered to have caused damage and bleeding. The patient was discharged from the hospital with a good postoperative course and is being followed-up in the outpatient department.

Longitudinal Associations of Perceived Mastery and Constraints With Coping and Their Implications for Functional Health for Aging Adults.

The present study examined longitudinal associations of distinct dimensions of perceived control (i.e., perceived mastery and constraints) with approach and avoidance coping relating to functional health for aging adults, which had not been well studied previously. Using data from two waves of Midlife in the United States (N = 4,963, whose mean age was 55.4 [SD = 12.5]), a longitudinal path model was analyzed for direct and indirect effects among perceived mastery and constraints, approach and avoidance coping, and functional limitations. Bidirectional associations were observed between perceived mastery and approach coping and between perceived constraints and avoidance coping. Moreover, perceived constraints not only were directly associated with functional limitations but also mediated the longitudinal associations of the other factors of interest with functional limitations. These findings can inform future research on perceived control and coping in the context of promoting functional health.

Longitudinal Implications of Social Integration for Age and Gender Differences in Late-Life Physical Functioning.

Social integration has documented benefits for late-life health; yet, little is known about its impacts on trajectories of physical functioning. This study examines age and gender differences in the longitudinal associations between social integration and activities of daily living (ADLs) using a hierarchical linear model with three waves of survey data collected over 4 years from the Social Integration and Aging Study (N = 400; baseline mean age = 80.3). Findings indicated some interaction effects of age, gender, and/or social integration on ADL trajectories. Among those of more advanced age, women showed greater increases in ADL limitations than men, and individuals with lower social integration experienced greater increases in ADL limitations than those with higher social integration. Neither of these patterns were found among younger older adults. This study highlights the benefits of longitudinal research on social integration and the need to explore practical interventions for promoting social integration particularly among the oldest older adults.

Longitudinal Stress-Buffering Effects of Social Integration for Late-Life Functional Health.

Stress can negatively affect multiple aspects of health, including functional health, among older adults, who are likely to face unique, age-related stressful experiences. Previous research has addressed the protective effects of social relations (i.e., social ties, social participation, and social integration) for physical and mental health outcomes, yet few studies have examined functional health. This study aimed to investigate the longitudinal stress-buffering effects of social integration on late-life functional health. Using three-wave data from 399 older adults (aged older than 60 years), two-level hierarchical linear modeling analysis was conducted and the results indicated that in addition to its main effect on functional (activity of daily living) limitations, social integration moderated the negative effect of stress on the longitudinal trajectory of functional limitations. The findings suggest important directions of future research to identify the mechanisms of such buffering effects over time and develop effective interventions to enhance late-life functional health while promoting social integration.

Longitudinal Associations Between Personal Growth and Cognitive Functioning in Adulthood.

OBJECTIVES: While personal growth has been found to be associated with multiple aspects of health in adulthood, its associations with cognitive functioning have not been fully understood. The present study aimed to assess both directions of such longitudinal associations. METHOD: Using data from the second wave (Time 1 [T1]) and third wave (Time 2 [T2]) of the Midlife in the United States (MIDUS) study (N = 4,206; mean age = 56.0 [standard deviation (SD) = 12.3]), a longitudinal measurement model containing latent variables of episodic memory and executive function was first constructed. Built on the measurement model, a cross-lagged panel model was analyzed to assess relationships between personal growth and the two areas of cognitive functioning, in which T1 personal growth predicted residualized changes in episodic memory and executive function, and T1 episodic memory and executive function predicted change in personal growth, controlling for covariates. RESULTS: T1 personal growth significantly predicted smaller decreases in episodic memory, whereas it did not predict change in executive function. T1 episodic memory, but not T1 executive function, significantly predicted smaller decreases in personal growth. DISCUSSION: The present findings were unique, particularly implying potential longitudinal reciprocity between personal growth and episodic memory. These findings and implications can inform future research aimed at exploring approaches to promoting personal growth and cognitive functioning among aging adults.

Longitudinal Associations of Conscientiousness and Neuroticism With Perceived Mastery and Constraints for Aging Adults.

It has not been well understood how conscientiousness and neuroticism are associated with two related but distinct dimensions of perceived control (i.e., perceived mastery and constraints) among aging adults. The present study examined these associations and their change over time, while addressing whether they differ by age or gender. For respondents aged 50+ at baseline (N = 2,768) in the Midlife in the United States (MIDUS) study, multilevel modeling analyses were conducted to assess how conscientiousness and neuroticism predicted perceived mastery and constraints over 2 decades. As expected, higher conscientiousness and lower neuroticism (for both between- and within-person variability) predicted higher perceived mastery and lower perceived constraints overall. Nuanced findings emerged related to age, gender and change over time for different associations of conscientiousness and neuroticism with the outcomes. These findings can inform future research suggesting directions of further investigations for these complex associations.

Surgical treatment of scoliosis using allograft bone from a regional bone bank.

INTRODUCTION: Routine spinal fusion techniques have involved removal of all soft tissues and articular facets, decortication of all posterior elements, and application of bone graft to the fusion area. Bone grafting has been performed mainly using the patient's own bone (autograft bone), most commonly from the iliac crest. The use of autograft bone is accompanied by complications or problems because of harvesting and donor-site morbidity. Several studies have already reported the use of allograft bone in scoliosis surgery. However, these studies are small series with short-term follow-up. METHOD: Twenty-two patients with scoliosis who underwent posterior spinal fusion and pedicle-screw-alone fixation using banked allograft bone obtained from the regional bone bank in Japan were analyzed. The average age at surgery was 13 years 5 months. The average follow-up was 2 years 7 months, and the average age at the last follow-up was 15 years 6 months. Scoliosis curves were divided into two groups (single curve group and double curve group). RESULTS: For the single curve group, the average preoperative coronal curve measured 78° (48°-85°) and the postoperative curve measured 22° (8°-35°), with no loss of correction at the last follow-up. For the double curve group, the average preoperative thoracic curve measured 64° (48°-85°) and the lumbar curve measured 42° (38°-60°). The average postoperative thoracic curve measured 12° (8°-34°) and lumbar curve measured 15° (8°-32°), with no significant loss of correction at the last follow-up. No patients had clinical complaints in the region of surgery at 9 months after surgery and thereafter. There were no complications including loss of correction, nonunion, infection and instrumentation failure. At the last follow-up, patients/parents were interviewed and asked to complete an outcome satisfaction questionnaire. They were asked to rate the outcome as very satisfactory, satisfactory, neither satisfactory nor unsatisfactory, unsatisfactory, or very unsatisfactory. Seventeen patients (77%) were very satisfied, four patients (17%) were satisfied, and one patient (6%) was neither satisfied nor unsatisfied. Autograft bone and banked allograft bone appear to yield comparable results and clinical outcomes. CONCLUSION: However, in Japan, various expenses accrue to supply a safe and premium quality of banked allograft bone. Financial issue must be resolved as soon as possible.

Longitudinal Associations Between Perceived Control and Health for American and Japanese Aging Adults.

BACKGROUND AND OBJECTIVES: Research suggests longitudinal and reciprocal relationships between perceived control over life circumstances and health for Western populations; yet, such associations have not been fully understood for non-Western populations. The present study addresses cultural differences in these associations for American and Japanese aging adults. RESEARCH DESIGN AND METHODS: For respondents aged 40 and older at 2 waves (Time 1 [T1] and Time 2 [T2]) of Midlife in the United States (N = 4,455) and Midlife in Japan (N = 827), cross-lagged path models were analyzed for T1 perceived control predicting change in each health measure (i.e., self-rated health, number of chronic health conditions, and functional limitations) from T1 to T2; and the matched T1 health measure predicting change in perceived control from T1 and T2. In these analyses, the effects of T1 age, T1 perceived control, and each T1 health measure were compared cross-nationally. RESULTS: A cross-national difference emerged in that T1 perceived control predicted change in chronic health conditions only for Americans. Similar tendencies were found between the 2 nationalities for T1 perceived control predicting changes in self-rated health and functional limitations. Reciprocal relationships between perceived control and health measures were found for Americans, but neither age nor any of the T1 health measures predicted change in perceived control for the Japanese respondents. DISCUSSION AND IMPLICATIONS: The findings suggest cultural differences and similarities between the 2 nationalities, which have implications for potential health benefits of enhancing perceived control among American and Japanese aging adults. Building on these findings, the present study also indicates future directions of research.

Two-year results for scoliosis secondary to Duchenne muscular dystrophy fused to lumbar 5 with segmental pedicle screw instrumentation.

BACKGROUND: Instrumentation and fusion to the sacrum/pelvis has been a mainstay in the surgical treatment of scoliosis in patients with Duchenne muscular dystrophy since the development of the intrailiac post. It is recommended for correcting pelvic obliquity. However, caudal extent of instrumentation and fusion has remained a matter of considerable debate. This study was performed to determine the efficacy and safety of stopping segmental pedicle screw constructs at L5 during surgical treatment of scoliosis associated with Duchenne muscular dystrophy (DMD). METHODS: From May 2005 to June 2007, a total of 20 consecutive patients underwent posterior spinal fusion and segmental pedicle screw instrumentation only to L5 for scoliosis secondary to DMD. All patients had progressive scoliosis, difficulty sitting, and back pain before surgery. A minimum 2-year follow-up was required for inclusion in this study. Assessment was performed clinically and with radiological measurements. The Cobb angles of the curves and spinal pelvic obliquity were measured on the coronal plane. Thoracic kyphosis and lumbar lordosis were measured on the sagittal plane. These radiographic assessments were performed before surgery, immediately after surgery, and at a 3-month interval thereafter. The operating time, blood loss, and complications were evaluated. Patients were questioned about whether they had difficulty sitting and felt back pain before surgery and at 6 weeks, 1 year, and 2 years after surgery. RESULTS: A total of 20 patients, aged 11-17 years, were enrolled. The average follow-up period was 37 months. Preoperative coronal curves averaged 70 degrees (range 51 degrees -85 degrees ), with a postoperative mean of 15 degrees (range 8 degrees -25 degrees ) and a mean of 17 degrees (range 9 degrees -27 degrees ) at the last follow-up. Pelvic obliquity improved from 13 degrees (range 7 degrees -15 degrees ) preoperatively to 5 degrees degrees (range 3 degrees -8 degrees ) postoperatively and 6 degrees (range 3 degrees -9 degrees ) at the last follow-up. Good sagittal plane alignment was recreated and maintained. Only a small loss of correction of scoliosis and pelvic obliquity was noted. The mean operating time was 271 min (range 232-308 min). The mean intraoperative blood loss was 890 ml (range 660-1260 ml). The mean total blood loss was 2100 ml (range 1250-2880 ml). There was no major complication. All patients reported that difficulty sitting and back pain were alleviated after surgery. CONCLUSION: Segmental pedicle screw instrumentation and fusion only to L5 is safe and effective in patients with DMD scoliosis of <85 degrees and pelvic obliquity of <15 degrees . Good sagittal plane alignment was achieved and maintained. All patients benefited from surgery in terms of improved quality of life. There was no major complication.

Electrical storm 11 days after acute myocardial infarction: a case report.

BACKGROUND: The definition of electrical storm is still debated. For example, an electrical storm is defined as a clustering of three or more separate episodes of ventricular tachycardia/ventricular fibrillation within 24 hours or one or more episodes occurring within 5 minutes of termination of the previous episode of ventricular tachycardia/ventricular fibrillation. When it is refractory to medications, prompt assessments by coronary angiography, sedation, and overdrive pacing should be performed. An electrical storm may occur anytime, including at night or after the patient leaves an intensive care unit. CASE PRESENTATION: A 70-year-old Japanese man with type 2 diabetes mellitus was diagnosed as having ST-elevation myocardial infarction. His clinical course after an urgent percutaneous coronary intervention was uneventful, but he developed electrical storm that was refractory to antiarrhythmic medications on day 11 of hospitalization. We used sedative medications and performed ventricular overdrive pacing and transferred him to a university hospital for further treatment, which included electrical ablation and cardioverter-defibrillator implantation. CONCLUSION: An electrical storm is a relatively rare and fatal complication of acute myocardial infarction. It is important that the treatment choices for this condition are known by non-cardiologist physicians who might encounter this rare condition.

Clinical significance of reversed R wave progression in right precordial leads.

Objective: Poor R wave progression in right precordial leads is a relatively common electrocardiogram (ECG) finding that indicates possible prior anterior myocardial infarction (MI); however, it is observed frequently in apparently normal individuals. In contrast, reversed R wave progression (RRWP) may be more specific to cardiac disorders; however, the significance of RRWP in daily clinical practice is unknown. The purpose of this study was to clarify the significance of RRWP in clinical practice. Materials and Methods: We analyzed consecutive ECGs obtained from 12,139 patients aged ≥20 years at Mito Kyodo General Hospital in Ibaraki between November 2009 and August 2012. Our setting is a secondary emergency hospital in the community, and the study participants were inpatients or patients who visited the general or emergency outpatient departments. RRWP was defined as RV2 < RV1, RV3 < RV2, or RV4 < RV3. Regarding ECGs considered to show RRWP, we confirmed the presence or absence of an abnormal Q wave and whether ultrasound cardiography, contrast-enhanced computed tomography, coronary angiography, and/or left ventriculography were performed to obtain detailed information. Results: RRWP was identified in 34 patients (0.3%). Among these patients, 29 (85%) had undergone cardiac evaluation. The final diagnosis was previous anterior MI in 12 patients (41%) and ischemic heart disease (IHD) without MI in 5 patients (17%). All 17 patients with IHD had left anterior descending (LAD) artery stenosis. The other patients were diagnosed with dilated (two patients, 7%) and hypertrophic (one patient, 3%) cardiomyopathy, left ventricular hypertrophy (one patient, 3%), or pulmonary embolism (one patient, 3%). Only seven patients (24%) were normal. Conclusions: RRWP is rare in daily clinical practice; however, it is a highly indicative marker for cardiac disease, particularly IHD with LAD artery stenosis.

Edge-to-edge technique to repair mitral commissural prolapse.

OBJECTIVE: Repair for mitral commissural prolapse can represent a challenging surgical problem. Although there are various reports of repair for mitral commissural prolapse, the technique is not necessarily simple. There are few reports of repair by the edge-to-edge suture for commissural prolapse, and the results are not entirely clarified. We report the application and early and intermediate outcome of this technique for mitral commissural prolapse. METHODS: From January 1999 to April 2005, a total of 12 patients with commissural prolapse due to degenerative disease were operated on using the edge-to-edge technique. The patients were seven men and five women with a mean age of 48.5 years. The mechanism of the regurgitation was chordal rupture in nine patients and chordal elongation in three patients. RESULTS: There were no in-hospital deaths or complications. Postoperative echocardiography demonstrated that regurgitation had disappeared in nine patients, was trivial in two patients, and was mild in one patient. During the follow-up period (mean 49.8 +/- 22.0 months) all patients lived vigorously, and no recurrence or aggravation of regurgitation or valve-related complications were observed. CONCLUSIONS: It seems that the edge-to-edge technique for mitral commissural prolapse due to degenerative disease is a technically simple, highly effective procedure.

4. The Low-Intensity Pulsed Ultrasound (LIPUS) Mechanism and the Effect of Teriparatide on Fracture Healing.

Low-Intensity Pulsed Ultrasound (LIPUS) provided a mechanical stimulus, and was thought to promote fracture healing by signal transduction through integrin, a cytoskeletal protein. Meanwhile, teriparatide, a drug for osteoporosis treatment, showed efficacy in promoting bone metabolism. This drug also appeared to prevent fractures in patients with serious osteoporosis by improving bone mineral density and bone quality, which in turn resulted from promoting action for bone metabolism. Further, clinical trials and fundamental research reported that teriparatide demonstrated the effect of promoting fracture healing. Mechanical stimulus by LIPUS had a topical effect on fractures; on the other hand, teriparatide (peptide hormone) had both topical and systemic effects. Both LIPUS and teriparatide had the effect of fracture healing, but it was supposed that the characteristics of each effect were different because of the different mechanism of action. Moreover, the combination therapy of LIPUS and teriparatide was expected to produce synergies. We used elderly rats as models for the femoral fracture to examine the effects of LIPUS and teriparatide on promoting fracture healing for treatment delay by aging. We observed the fracture healing process in 40-week-old rats as an elderly model using simple radiographs, and recognized a delay in fracture healing compared with that of 8-week-old rats. As discussed in histomorphology, it was demonstrated that the period of endochondral ossification, from chondrogenesis to teleost cross-linked callus, was prolonged and the fracture healing process was delayed by aging. Next, we treated the elderly fracture models with LIPUS for 20 minutes a day from the first day after the fracture, and compared them with non-treated models. The bone unions of the treated models were observed earlier than those of non-treated models in the simple radiographs. LIPUS shortened the period of endochondral ossification. Further, we gave the elderly fracture models teriparatide subcutaneously 5 µg/kg three times a week from the first day after the fracture. Bone unions of the treated models were observed earlier than those of non-treated models in simple radiographs as well. In micro CT analysis, it was demonstrated that lamellar bone transforming and bone remodeling of the trabecular structure of external callus were especially accelerated. The results of these trials showed that both LIPUS and teriparatide demonstrated the effect of promoting fracture healing, and each had unique characteristics.

12. Influence of Wound Dressing on the Fracture Healing Effect of Low-Intensity Pulsed Ultrasound (LIPUS).

OBJECTIVE: We have conducted a basic study on the influences on ultrasonic properties when LIPUS is applied through wound dressing. According to the results of ex vivo experiments conducted to date, LIPUS showed ultrasonic properties such as transmittance, coefficient of transmission, and a non-uniformity ratio through film wound dressing better than other wound dressing, and it was considered that LIPUS's effect for fracture healing was not influenced by film wound dressing. Then, we discussed the influence on the effect of LIPUS through film wound dressing. METHODS: Thirty male 8-week-old Sprague-Dawley rats were used for the trial. After creating close transverse femoral fractures on the right legs of these 30 rats, they were divided into 3 groups of 10; LIPUS through wound dressing (Group A), LIPUS without wound dressing (Group B), and No LIPUS treatment (Group C). OPSITE Wound, which was thought to have the least influence on ultrasound properties, was used for this trial. Group A and B received LIPUS for 20 minutes a day from the first day after the fractures. LIPUS was generated from Teijin Pharma's device for a basic experiment. When treating Group A, the wound dressing was pasted on the ultrasound terminal in order to apply LIPUS through the dressing. We assessed the time-oriented morphological change of each group in anesthetized condition using simple radiographs on the 8th, 16th, and 24th day after the fractures. RESULTS: Six rats in Group A, 2 in Group B, and 1 in Group C died in anesthesia, and we discussed the remaining 4 rats in Group A, 8 in Group B, and 9 in Group C. We defined more than one teleost callus bridging as bone-union. We also counted a bone remodeling when we recognized the absorption of existing cortical bone and the transformation of new bone to cortical bone in simple radiographs. As a result, compared with Group C, we recognized that both bone union and remodeling accelerated remarkably in Group B, but not in Group A. DISCUSSION: It suggested that LIPUS through wound dressing had negative influences on both period shorting of fracture healing and bone remodeling. When LIPUS was conducted through film wound dressing, transmittance and coefficient of transmission were unchanged; however, the non-uniformity ratio changed slightly. The non-uniformity ratio of the ultrasound transducer had a significant influence on the effect of LIPUS on fracture healing.

A model for predicting angiographically normal coronary arteries in survivors of out-of-hospital cardiac arrest.

BACKGROUND: It has been recommended that all survivors of out-of-hospital cardiac arrest (OHCA) have immediate coronary angiography (CAG), even though it has been reported that half of the survivors have normal coronary arteries. Our aim was to develop a model which might identify those who have angiographically normal coronary arteries. Reliable prediction would reduce unnecessary CAG. METHODS: A retrospective, observational, cohort study was conducted on 47 consecutive adult survivors who received immediate CAG after resuscitation from OHCA, between June 1, 2006 and March 31, 2011. We analyzed the clinical and electrocardiographic characteristics of the survivors with and without normal coronary arteries. RESULTS: All subjects had CAG. Normal coronary arteries were found in 25/47. These persons did not have diabetes mellitus (p = 0.0069) or a history of acute coronary syndrome (ACS) (p = 0.0069). Any abnormality of the ST segment or ST segment elevation on electrocardiogram (ECG) was strongly related to abnormal coronary arteries (p = 0.0045 and p = 0.0200, respectively). The partitioning model for predicting angiographically normal coronary arteries showed that all patients (8/8) with no ST segment change on their ECG had normal coronary arteries. Eight out of ten patients with ST segment abnormalities also had normal coronary arteries with a history of arrhythmia without a history of ACS. CONCLUSIONS: Survivors of OHCA who have no history of diabetes mellitus, who have no past history of ACS, and who present with no ST segment abnormalities may not require urgent/emergent CAG. Further studies are needed to guide clinicians in the determination of emergent cardiac catheterization following resuscitation of OHCA.

Diabetes and obesity are significant risk factors for morning hypertension: from Ibaraki Hypertension Assessment Trial (I-HAT).

AIMS: Although morning hypertension (HT) has been identified as a major cardiovascular risk, susceptible populations remain unknown. This study aimed to clarify the relationship between morning HT and diabetes or obesity in a large-scale population. MAIN METHODS: Clinic blood pressure (BP) and BP upon awakening were recorded in 2554 outpatients with HT who attended 101 clinics or hospitals for two weeks. Mean clinic and awakening BP>140/90 and >135/85 mmHg, respectively, were considered as HT. The patients were classified according to values for clinic and home BP, into normal BP, white coat HT, masked HT, and sustained HT. KEY FINDINGS: Morning BP (mmHg) significantly and progressively elevated in the order of normal glucose tolerance, impaired glucose tolerance and diabetes (134.1 ± 12.2, 135.4 ± 13.1 and 137.5 ± 11.5; p<0.0001). The incidence of morning HT significantly increased and progressively in the same order (53.4%, 55.6%, 66.4%, p<0.0001). Morning BP was significantly higher among obese patients with diabetes than among non-obese and non-diabetic patients (138.8 ± 10.5, 133.1 ± 11.9, p<0.0001). In addition, the incidence of morning HT was significantly higher in obese diabetic patients than in non-obese and non-diabetic patients (73.0% vs. 49.9%, p<0.0001). SIGNIFICANCE: Diabetic or obese patients frequently have morning HT.

Effect of hospital case volume on treatment and in-hospital outcomes in patients undergoing percutaneous coronary intervention for acute myocardial infarction. Results from the Ibaraki Coronary Artery Disease Study (ICAS) Registry.

The volume of percutaneous coronary interventions (PCI) performed in a hospital has been suggested to correlate with favorable outcomes in patients undergoing primary PCI for acute myocardial infarction (AMI). However, studies that use current data and compare treatment and outcomes for AMI among hospitals with different volumes are still limited in Japan. Between January 2004 and March 2006, 401 AMI patients underwent primary PCI in the 11 hospitals participating in the Ibaraki Coronary Artery Disease Study (ICAS). Clinical characteristics, treatment, and in-hospital outcomes were retrospectively compared between 254 patients admitted to high-volume PCI hospitals and 147 patients admitted to low-volume hospitals. Low-volume hospitals had a higher prevalence of multivessel disease patients. High-volume hospitals had longer onset-to-door times, which were offset by faster door-to-balloon times. Rates of coronary stent use and successful PCI were comparable between the groups. Low-volume hospitals more frequently performed intra-aortic balloon pumping. Length of stay was longer in low-volume hospitals, whereas in-hospital mortality, bypass surgery, and repeat PCI rates did not differ between groups. Although the present study assessed limited data based on small sample size, we observed that contemporary standard treatments including stent implantation were performed for AMI patients undergoing primary PCI in hospitals with both high and low case volumes. We did not find an obvious relationship between hospital PCI volume and in-hospital outcomes in our data. However, further prospective surveys should be attempted to confirm these results.

Hybrid origins and F1 dominance in the free-floating, sterile bladderwort, Utricularia australis f. australis (Lentibulariaceae).

Abandonment of sexual reproduction is a well-known characteristic in aquatic plants, while the causes, levels, and consequences of sterility are often unknown. Utricularia australis f. australis (Lentibulariaceae) is a free-floating, sterile bladderwort distributed widely in temperate and tropical regions. Experimental crosses in cultivated conditions, AFLP analysis, and cpDNA haplotypes of natural populations clearly demonstrated that U. australis f. australis originates from the asymmetric hybridization between two parental taxa: U. australis f. tenuicaulis (mostly as female) and U. macrorhiza (mostly as male). No post-F(1) hybrids were detected using the additive patterns of AFLP bands combined with the observation of extensive sterility in U. australis f. australis. Recurrent hybridizations and subsequent perpetuation by asexual reproduction were demonstrated by the unique, but monomorphic, AFLP genotypes observed in each U. australis f. australis population. Hybrids and parental species did not coexist, implying the superiority of the hybrid U. australis f. australis in certain environmental conditions. It remains unclear whether populations of U. australis f. australis are maintained by colonizing propagules or as relicts of past hybridization events.

Assessing muscle vasodilation using near-infrared spectroscopy in cardiac patients.

BACKGROUND: In patients with chronic heart failure, an inadequate increase in muscle blood flow resulting from impaired vasodilation plays a key role in their exercise intolerance. However, no non-invasive methods to assess muscle vasodilation during dynamic exercise were available. We investigated whether the changes in tissue hemoglobin and myoglobin content (total-Hb + Mb) determined by non-invasive measurement using near-infrared spectroscopy (NIRS) reflect vessel conductance of working muscle during exercise. METHODS AND RESULTS: Sixteen patients (10 patients with normal cardiac systolic function, 6 with cardiac dysfunction) performed incremental bicycle exercise testing. Total-Hb + Mb from the right vastus lateralis muscle was monitored using NIRS. Leg blood flow (LBF) in the right femoral vein was measured using a thermodilution technique every 30-60 s. Leg vessel conductance was calculated as LBF/mean arterial pressure at each time of the measurement. In all cases except 1, the levels of total-Hb + Mb showed significant correlation with the leg vessel conductance (r=0.792 to 0.980). Intra-subject reproducibility of the NIRS measurement was also confirmed in 6 patients. CONCLUSIONS: Total-Hb + Mb from NIRS reflected muscle vasodilation during sub-maximal dynamic exercise in patients with and without cardiac dysfunction, indicating that NIRS provides a valuable method to assess the working muscle vasodilation.