Continuous versus intermittent exercise effects on urinary excretion of albumin and total protein

Several studies have reported post-exercise increases of urinary concentrations of plasma proteins. However, under normal conditions, through mechanisms of size and electrical charge selection, the kidney restricts the clearance of molecules as large as albumin. Post-exercise increases in albuminuria occur following the physiological stress of intense exercise, most likely as a result of the exercise induced blood acidity changes which lead to a change in the arrangement of the albumin molecule, and subsequently the filtration characteristics of the glomerular capillary wall. The purpose of the present study was therefore to determine the extent to which different types of exercise could induce a transient condition of post-exercise increases in the urinary output of total protein and albumin. All 14 males, who agreed to participate in the study, performed a continuous and an intermittent cycling protocol on a stationary bicycle ergometer. The results showed that: a) intermittent exercise had a greater influence than continuous exercise on the total output of urine albumin, and of urine total protein; b) concentrations of blood pH and blood lactate, were associated with changes in the clearance of urine albumin and urine total protein. Post-exercise proteinuria response seems to be transient and therefore renal trauma is not suspected at the early stages of observation. Furthermore, these results indicate that the kidney undergoes distinct physiological adjustments during exercise, and that these adjustments are relative to the intensity of the exercise stress.     

Kawasaki disease presenting as cervical lymphadenitis or deep neck infection.

OBJECTIVE: To describe a group of patients with Kawasaki disease who had cervical lymphadenopathy as their dominant initial presentations. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 14 children who were admitted to Chang-Gung Children's Hospital between May 1996 and July 1998 with the initial impression of cervical lymphadenitis, cellulitis, and/or deep neck infection but for which a diagnosis of Kawasaki disease was established later. RESULTS: Five (35.7%) patients were less than 5 months of age, and 8 (57.1%) patients were more than 53 months of age. The mean duration for establishing a diagnosis of Kawasaki disease from the onset of illness was 8.2 (6 to 20) days. Initially, empiric antibiotics were prescribed in each case with unsatisfactory response. Intravenous immune gamma globulin (2 g/kg) was administered in 13 patients. Three (21.4%) patients developed coronary artery lesions. CONCLUSION: If a child less than 6 months or more than 4 years of age has a fever and an enlarged cervical lymph node and is unresponsive to empiric antibiotics, Kawasaki disease should be considered.     

Vocal learning and flexible rhythm pattern perception are linked: Evidence from songbirds

Rhythm perception is fundamental to speech and music. Humans readily recognize a rhythmic pattern, such as that of a familiar song, independently of the tempo at which it occurs. This shows that our perception of auditory rhythms is flexible, relying on global relational patterns more than on the absolute durations of specific time intervals. Given that auditory rhythm perception in humans engages a complex auditory–motor cortical network even in the absence of movement and that the evolution of vocal learning is accompanied by strengthening of forebrain auditory–motor pathways, we hypothesize that vocal learning species share our perceptual facility for relational rhythm processing. We test this by asking whether the best-studied animal model for vocal learning, the zebra finch, can recognize a fundamental rhythmic pattern—equal timing between event onsets (isochrony)—based on temporal relations between intervals rather than on absolute durations. Prior work suggests that vocal nonlearners (pigeons and rats) are quite limited in this regard and are biased to attend to absolute durations when listening to rhythmic sequences. In contrast, using naturalistic sounds at multiple stimulus rates, we show that male zebra finches robustly recognize isochrony independent of absolute time intervals, even at rates distant from those used in training. Our findings highlight the importance of comparative studies of rhythmic processing and suggest that vocal learning species are promising animal models for key aspects of human rhythm perception. Such models are needed to understand the neural mechanisms behind the positive effect of rhythm on certain speech and movement disorders.

The perception of rhythmic patterns in auditory sequences is important for many species, ranging from crickets and birds recognizing conspecific songs to humans perceiving phrase boundaries in speech or beat patterns in music. Animals vary widely in the complexity of the neural mechanisms underlying rhythm perception. Female field crickets, for example, have a circuit of five interneurons that form a feature detector for recognizing the stereotyped pulse pattern of male song (1). At the other extreme, human rhythm perception engages a complex circuit including cortical auditory and premotor regions, the basal ganglia, cerebellum, thalamus, and supplementary motor areas that enable recognition of a given rhythmic pattern across a wide range of tempi (2, 3). Growing evidence suggests that human rhythm perception relies on auditory–motor interactions even in the absence of movement (4–7). Given that vocal learning species have evolved neural adaptations for auditory–motor processing, including specializations of premotor and basal ganglia regions, and communicate using acoustic sequences that are often rhythmically patterned (2, 8–12), we hypothesize that such species are advantaged for flexible auditory rhythm pattern perception. This “vocal learning and rhythmic pattern perception hypothesis” focuses on perception in the absence of overt movement and is thus relevant to species that do not spontaneously synchronize movements to auditory rhythms.A key test of flexibility in rhythm pattern perception is determining whether an individual can recognize a temporal pattern in novel sequences with substantially different absolute time intervals than used during training. A simple example is recognition of isochrony, or equal time intervals between events, independent of absolute interval duration. Isochrony is a core feature of music, and humans easily recognize it as a global relational pattern between events, independent of tempi (13). Furthermore, isochrony has been reported as an underlying pattern in several forms of animal communication (8, 10, 14). Given the possible overlap in the circuitry for vocal learning and rhythm processing, our hypothesis predicts that vocal learners should be able to flexibly recognize isochrony in auditory sequences.A variety of prior studies are consistent with our hypothesis that robust auditory–motor neural interactions in vocal learning species enable flexible rhythmic pattern perception. Vocal nonlearning pigeons (Columbia livia) cannot learn to discriminate isochronous rhythms from arrhythmic sound patterns, though they can learn to categorize acoustic sequences based on the rate (versus rhythm) of events (15). Recently, rats (Rattus norvegicus), another vocal nonlearning species, were successfully trained to discriminate isochronous from arrhythmic sound sequences, but they showed only weak generalization when tested at novel tempi, thus exhibiting limited flexibility in auditory rhythm pattern perception (13). In contrast, in the same study, humans readily discriminated isochronous from arrhythmic sound sequences when tested at novel tempi (13). Prior work has also shown that starlings (Sternus vulgaris), a songbird that learns and increases its song repertoire throughout life, can learn to discriminate isochronous from arrhythmic sound patterns and robustly generalizes this discrimination when tested at novel rates (16). Together, these studies suggest that vocal learners recognize isochrony as a global, relational pattern rather than by simply memorizing specific temporal interval patterns (17). It is unclear, however, how prevalent flexible isochrony perception is among vocal learners. To address this question, a particularly interesting species is the zebra finch (Taeniopygia guttata), the best-studied animal model of vocal learning. Here, we ask whether zebra finches exhibit flexible temporal pattern perception. Male zebra finches (but not females) learn to sing temporally precise, hierarchically organized songs with structure on multiple timescales (18). Thus, we focus on the male zebra finch’s ability to recognize isochrony as a global temporal feature of sound sequences. This rhythmic pattern is a common feature in zebra finch song (10, 11), making them a good choice for rhythm research.Several lines of evidence suggest that zebra finches may be adept at flexible rhythm perception. First, like humans, zebra finches possess recurrent connections between auditory and motor regions specialized for learned vocalizations, and ablation of the motor-to-auditory pathway prevents the adaptive modification of song timing (19). Second, neurons in auditory association areas exhibit differential activation in response to hearing isochronous versus arrhythmic stimuli (20). More recently, predictive activity in the song motor pathway prior to anticipated calls has been reported during social call exchanges (21). Finally, several studies have shown that zebra finches can predict the timing of isochronous, antiphonal calls during vocal turn taking and can adjust their own call timing to avoid interference, an ability that is disrupted by manipulations of the song motor pathway (21–23). Taken together, these results are consistent with the notion that interactions between vocal motor and auditory regions may generate predictive timing signals that facilitate flexible rhythm perception.In contrast to the hypothesis that vocal learners are adept at flexible rhythm perception, other studies suggest limited rhythm perception abilities in zebra finches. Using an operant conditioning paradigm, ten Cate and colleagues found that zebra finches can learn to discriminate isochronous from arrhythmic patterns but show weak generalization when tested at novel tempi (9, 24). This led them to propose that zebra finches attend to specific, local features of temporal patterns, such as the exact duration of individual temporal intervals, rather than to global temporal structure. However, several factors may have contributed to underestimating the rhythm perception abilities of zebra finches. These include the use of artificial sounds and training with just one pair of isochronous and arrhythmic stimuli (or with short sequences), which may have resulted in attention to local features of the stimuli.Here, we take a different approach, employing longer temporal patterns composed of conspecific sounds and training birds sequentially using multiple sound types at different tempi. We first confirm that male zebra finches can discriminate isochronous from arrhythmic rhythms. Strikingly, in contrast to previous work, we find that male zebra finches can robustly generalize this discrimination to novel tempi distant from the training tempi, consistent with the idea that they can recognize rhythmic regularity based on global temporal patterns. This makes zebra finches a promising candidate for human-relevant neural research on rhythm perception, including the role of the motor system in rhythmic pattern perception. In particular, evolutionary parallels between avian and human vocal learning circuitry (12) make songbirds a tractable model for investigating the role of premotor and basal ganglia circuits in rhythm perception (25) and for exploring how and why rhythm processing deficits are associated with a variety of speech and motor disorders (26–29).     

Different duration of high-altitude pre-exposure associated with the incidence of acute mountain sickness on Jade Mountain

Objective

The objective of this study is to determine the association between the duration of high-altitude (> 3000 m) pre-exposure and acute mountain sickness (AMS) incidence.

Methods

A prospective observational study was conducted on 2 random days each month from April 2007 to March 2008 at Paiyun Lodge (3402 m), Jade Mountain, Taiwan. Demographic data, prior AMS history, symptoms, and scores and the days and times of high-altitude pre-exposure within the preceding 2 months were obtained from lowland (< 1500 m) trekkers.

Results

Totally, 1010 questionnaires were analyzed; 106, 76, and 828 trekkers had pre-exposure lasting at least 3 days (group 1), less than 3 days (group 2), and 0 days (group 3), respectively. Acute mountain sickness incidence was significantly higher in groups 2 and 3 than in group 1 (21.70%, 35.53%, 37.08%, respectively; P = .008). Logistic regression analysis indicated a significantly lower AMS risk in group 1 (group 1, P = .004; odds ratio [OR], 0.479; 95% confidence interval [CI], 0.290-0.791; group 2, P = .226; OR, 0.725; 95% CI, 0.430-1.221). In group 1, 28 and 78 trekkers had single and intermittent multiple pre-exposure, respectively. There was no difference in the incidence or severity of AMS symptoms between single and intermittent multiple pre-exposure (AMS, P = .838; headache, P = .891; dizziness or lightheadedness, P = .414; fatigue and/or weakness, P = .957; gastrointestinal symptoms, P = .257; difficulty sleeping, P = .804; AMS score, P = .796).

Conclusions

High-altitude pre-exposure lasting at least 3 days within the preceding 2 months was associated with a significant lower AMS incidence during a subsequent ascent among Jade Mountain trekkers.     

Patient Perceptions of Empowerment Processes,Health Outcomes and Related Factors in Patients Living with Diabetes in Taiwan: A Cross-Sectional Survey

Background: The aim was to examine the associations among empowerment processes, health outcomes, and related factors in patients living with diabetes. Methods: This cross-sectional study analyzed a convenience sample of 144 patients with diabetes in Taiwan. Data were collected with questionnaires, HbA1C, blood pressure, and total cholesterol. Findings: Empowerment processes were significantly associated with health outcomes, including self-care behaviors, quality of life, and HbA1C. Diabetes-related complications and treatment variables were associated with empowerment processes and health outcomes. Conclusions: To optimize the empowerment processes needed to promote the health of patients with diabetes, healthcare professionals should consider patient perceptions of empowerment processes and related factors.     

Antimicrobial activities of pomegranate rind extracts: enhancement by addition of metal salts and vitamin C

Background

Uncomplicated chronic rachialgia is a highly prevalent complaint, and one for which therapeutic results are contradictory. The aim of the present study is to evaluate the effectiveness and safety of treatment with auriculopressure, in the primary healthcare sector, carried out by trained healthcare professionals via a 30-hour course.

Methods/Design

The design consists of a multi-centre randomized controlled trial, with placebo, with two parallel groups, and including an economic evaluation. Patients with chronic uncomplicated rachialgia, whose GP is considering referral for auriculopressure sensory stimulation, are eligible for inclusion. Sampling will be by consecutive selection, and randomised allocation to one of the two study arms will be determined using a centralised method, following a 1:1 plan (true auriculopressure; placebo auriculopressure). The implants (true and placebo) will be replaced once weekly, and the treatment will have a duration of 8 weeks. The primary outcome measure will be the change in pain intensity, measured on a visual analogue scale (VAS) of 100 mm, at 9 weeks after beginning the treatment. A follow up study will be performed at 6 months after beginning treatment. An assessment will also be made of the changes measured in the Spanish version of the McGill Pain Questionnaire, of the changes in the Lattinen test, and of the changes in quality of life (SF-12). Also planned is an analysis of cost-effectiveness and also, if necessary, a cost-benefit analysis.

Discussion

This study will contribute to developing evidence on the use of auriculotherapy using Semen vaccariae [wang bu liu xing] for the treatment of uncomplicated chronic rachialgia.

Trial registration

Current Controlled Trials ISRCTN01897462.     

Culturing adult human bone marrow stem cells on gelatin scaffold with pNIPAAm as transplanted grafts for skin regeneration

Skin tissue engineering is a possible solution for the treatment of extensive skin defect. The ultimate goal of skin tissue engineering is to restore the complete functions of native skin, but until now the structures and functions of skins are only partially restored. By negative immunoselection (CD45 and glycophorin A), we isolated and cultivated adult human bone marrow stem cells (hBMSCs) that are of multilineage differentiation potential. In this study, we first demonstrated that by using gelatin/thermo-sensitive poly N-isopropylacrylamide (pNIPAAm) and the immunocompromised mice model, the hBMSCs possess the differentiation potential of epidermis and the capability of healing skin wounds. The in vitro observations and the results of the scanning electron microscope showed that the hBMSCs can attach and proliferate in the gelatin/thermo-sensitive pNIPAAm. To further monitor the in vivo growth effect of the hBMSCs in the skin-defected nude mice, the green fluorescence protein (GFP) gene was transduced into the hBMSCs by the murine stem cell viral vector. The results showed that the rates of cell growth and wound recovery in the hBMSC-treated group were significantly higher than those in the control group, which was only treated with the gelatin/pNIPAAm (p < 0.01). More importantly, the re-epithelialization markers of human pan-cytokeratin and E-cadherin were significantly increased on day 7, day 14, and day 21 after the hBMSC-scaffold with the pNIPAAM in the mice with skin defects (p < 0.05). Moreover, the stem cell markers of human CD13 and CD105 were gradually decreased during the period of wound healing. In sum, this novel method provides a transferring system for cell therapies and maintains its temperature-sensitive property of easy-peeling by lower-temperature treatment. In addition, the in vitro and in vivo GFP imaging systems provide a new imaging modality for understanding the differentiation process and the effective expression of stem cells in wound healing.     

High-fidelity evoked potential for mapping the rat tail in thalamus

The technique of field potentials (FPs) provides a macroscopic view for exploring brain function, and is supplementary to single-unit recording, a microscopic view that investigates each neuron in great detail. Mapping the rat tail in the ventroposterolateral (VPL) nucleus of the thalamus was carried out by analyzing the current source density (CSD) of the evoked FPs. The results showed a clear somatotopic organization of the tail in the VPL nucleus. Also, to obtain high-fidelity FPs, two recording parameters were determined. Based upon cross-correlation coefficient (rho), the cycles of FPs needed to be averaged should not be less than 50 and the distance between the two recording sites should be no longer than 50 mum in each direction (mediolateral, anteroposterior and ventrodorsal). Under these conditions, the representation (or reproducibility) of an FP can be >95%. The procedures used to determine these parameters can serve as a guide to obtain FPs with high signal-to-noise ratio and without spatial aliasing error.     

HIV-1 Vif promotes the formation of high molecular mass APOBEC3G complexes

HIV-1 Vif inhibits the antiviral activity of APOBEC3G (APO3G) by inducing proteasomal degradation. Here, we studied the effects of Vif on APO3G in vitro. In this system, Vif did not cause APO3G degradation. Instead, Vif induced changes in APO3G that affected immunoprecipitation of the native protein. This effect required wt Vif and was reversed by heat denaturation of APO3G. Sucrose gradient analysis demonstrated that wt Vif induced the gradual transition of APO3G translated in vitro or expressed in HeLa cells from a low molecular mass conformation to puromycin-sensitive high molecular mass (HMM) complexes. In the absence of Vif or the presence of biologically inactive Vif APO3G failed to form HMM complexes. Our results expose a novel function of Vif that promotes the assembly of APO3G into presumably packaging-incompetent HMM complexes and may explain how Vif can overcome the APO3G-imposed block to HIV replication under conditions of no or inefficient APO3G degradation.