Search

Purpose: This study examines long-term benefit on functional outcomes and quality of life after selective dorsal rhizotomy (SDR) in children with spastic diplegia in Hong Kong. Method: This is a case control study. Individuals with spastic diplegia who were at 6 to 12 years post-SDR were recruited. Age, gender, cognition, and Gross Motor Function Classification System level-matched individuals with spastic diplegia who had not undergone SDR were recruited as controls. Outcome measures included physical level, functional level, physiological level, and quality of life. All data were compared by independent t-test. Results: Individuals post-SDR (n = 15) demonstrated a significantly better range of ankle dorsiflexion in knee extension by − 5.7 ± 10.9° than the control group (n = 12). No other significant differences were observed. Conclusion: SDR is a safe, one-off procedure and provides long-term reduction in spasticity with no major complications. With the heterogeneity, we did not demonstrate between-group differences in long-term functional outcomes. [ABSTRACT FROM AUTHOR]

Cerebral palsy (CP) is an early onset, non-progressive, neuromotor disorder. Adolescence is the transition from childhood to adulthood when changes in physical and emotional aspects and self-perception occur further imposing an impact to quality of life (QoL) in individuals with CP. Cerebral Palsy Quality of Life (CP QoL) Teen is a questionnaire examining different domains of QoL for adolescents with CP. This study is aimed at translating and validating self-report and proxy-report CP QoL-Teen (HK). Prior approval of translation has been obtained. Forward and backward translations were performed following standardized translation procedures. Participants and their caregivers were asked to complete self-report and proxy-report CP QoL-Teen (HK), and Child Health Questionnaire (CHQ). Internal consistency and test–retest reliability were assessed by Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. Concurrent validity was evaluated by Spearman's rank correlation between subscales of CP QoL-Teen (HK) and CHQ as well as expanded and revised version of Gross Motor Function Classification System (GMFCS-E&R). Ninety-six participants completed the study. Of these, twenty participants completed CP QoL-Teen (HK) twice. Cronbach's α of CP QoL-Teen (HK) ranged from 0.84 to 0.95 suggesting excellent internal consistency. Moderate to excellent test–retest reliability were demonstrated in all subscales of CP QoL-Teen (HK) (self-report: ICC = 0.46–0.8; proxy-report: ICC = 0.40–0.72, p < 0.05). Weak to moderate association between subscales of CP QoL-Teen (HK) and CHQ (self-report: rs = 0.24–0.61; proxy-report: rs = − 0.41–0.60) was reported. Conclusion: This study showed that CP QoL-Teen (HK) has good psychometric properties. It is a valid and reliable tool to assess quality of life of adolescents with CP. What is Known: • Cerebral Palsy Quality of life-Teen (CP QoL-Teen) is a validated tool with strong psychometric properties and clinical utility in gauging the QoL in adolescents with CP during their transition from childhood to adulthood when changes in physical and emotional aspects and self-perception occur. Yet, a locally validated tool is lacking in measuring the QoL for adolescents with CP in Hong Kong. What is New: • The Chinese translated version CP QoL-Teen (HK) is a valid and reliable tool to assess quality of life of adolescents with CP tailoring to the local cultural and social background with good psychometric properties being demonstrated. [ABSTRACT FROM AUTHOR]

Experiments on fire whirls generated by a gasoline pool fire in a vertical shaft were carried out. Vortex motions of swirling flame induced by buoyancy above the pool fires were observed to be more vigorous with increase in height. Upward flame motions were resulted due to increase in buoyancy. The phenomenon was described mathematically by solving the vorticity transport equation with reasonable assumptions and appropriate boundary conditions. Analysis gave swirling attenuation along the vertical direction. By measuring heat release rates and fire whirl diameters at different heights, vertical variation of circular speeds of fire whirls was derived. [ABSTRACT FROM AUTHOR]

Ocular perivascular epithelioid cell tumor (PEComa) is exceedingly rare. We reported two examples involving the choroid and subconjunctival tissue, respectively, in patients aged 17 and 20 years. Both tumors comprised packets and sheets of large polygonal cells with moderately pleomorphic nuclei and prominent nucleoli, traversed by delicate fibrovascular septa. Melanin pigmentation was present in one case. The tumors showed HMB45 and TFE3 immunoreactivity. TFE3 gene translocation was confirmed by FISH break-apart probes. RNA seq revealed PRCC-TFE3 and NONO-TFE3 fusions, with the former representing the first description of PRCC-TFE3 in PEComa. Critical reappraisal of the reported cases showed that ocular PEComa frequently affected young patents with melanin pigmentation, frequent TFE3 protein expression, and/or TFE3 gene translocation. No recurrence or metastasis was reported after complete excision despite the presence of cytologic atypia. [ABSTRACT FROM AUTHOR]

Numerical simulation on turbulent flame propagation in premixed gas deflagration process in a tube will be reported in this paper, aiming at identifying the key factors affecting flame shape and flame velocity. Large eddy simulation with premixed gas combustion model is used to obtain results validated by full-scale experimental data. The effect of flow velocity and turbulence on flame propagation is discussed. The flow velocity of premixed gas is observed to be one of the main factors determining flame shape and affecting flame propagation process. The velocity difference of different parts of the flame front, both in magnitude and direction, will lead to tulip-shaped flame. Turbulence would accelerate the propagation of flame periodically. The cause of flame acceleration of low-intensity turbulence originates from two factors, namely, combustion and flow field, which transfer the heat and mass of chemical reaction from diffusion to vortex transport. As high-intensity turbulence will not affect the chemical reaction and the turbulent burning velocity, flame acceleration is controlled only by the characteristics of the flow field. [ABSTRACT FROM AUTHOR]

Study of smoke movement or air flow due to fire in sloping tunnels is important in designing smoke control systems. In contrast to a horizontal tunnel, there is an acceleration along the longitudinal axis due to smoke buoyancy. This phenomenon together with thermal radiation would lead to a complicated heat transfer mechanism of the ceiling jet in sloping tunnels. In the present work, thermally induced air flow arising from fire in sloping tunnels was studied via numerical simulations using the Computational Fluid Dynamics code FLUENT. Prior to the application of FLUENT in simulating the air flow under different conditions, scale model experiments were carried out and the results were compared with simulation results, to establish the reliability of FLUENT in simulating fires in sloping tunnels. For this purpose, a tunnel section model of length 3 m, width 0.8 m and height 1 m was constructed, with a 1.5 kW electrical heating source to model fire. Hot air movement pattern driven by the electric heater was studied with the tunnel inclined at 0°, 10°, 20° and 30° to the horizontal. Four cases of the same configuration as the scale tunnel experiments were simulated using FLUENT, with predicted results agreeing well with experimental results. Having established the suitability of FLUENT in simulating air flow due to fire in sloping tunnels, numerical simulations were carried out to study air flow in sloping tunnels with different scenarios, that is, for tunnels with different gradients and with fire located at different positions in the tunnel. Macroscopic number on heat transfer, including the Rayleigh number Ra, the average and local Nusselt number Nuave for sloping tunnels were also studied from the measured results. The correlation between Nuave and Ra, which shows the effect of hydrodynamic properties on relative dominance of heat transfer in tunnel fire, was also discussed. [ABSTRACT FROM AUTHOR]

One of the key challenges in water treatment industry is the removal of organic compounds by cost-effective methods. This study evaluated the adsorptive removal of dissolved organic carbon (DOC) from reservoir water using fuller’s earth (FE) in comparison with natural (SQ) and modified quartz (MSQ) sands. The removal capacities of FE at different contact times, pH levels, adsorbent dosages and initial DOC concentrations were compared with both the quartz sands. The optimum DOC removals by FE and SQs were achieved at contact time of 60 and 30 min, pH level of 6 and 4, and at adsorbent dose of 1.5 g/150 mL and 10 g/100 mL, respectively. The adsorption capacity of FE (1.05 mg/g) was much higher compared to the MSQ (0.04 mg/g) and SQ (0.01 mg/g). Adsorption equilibrium data better fitted to the Freundlich model than to the Langmuir model, suggesting that adsorption occurred primarily through multilayer formation onto the surfaces of FE and SQ. The pseudo-second-order model described the uptake kinetics more effectively than the pseudo-first-order and intra-particle diffusion models, indicating that the mechanism was primarily governed by chemisorption. These observations were well supported by the physiochemical characteristics and charge behaviour of the adsorbents. In mass-transfer study, the results of liquid film diffusion model showed that the adsorption of DOC on FE was not controlled by film diffusion, but other mechanisms also played an essential role. This study demonstrates that FE is an effective adsorbent for the removal of DOC in surface water treatment. [ABSTRACT FROM AUTHOR]

An explosion while repairing liquefied petroleum gas (LPG) taxis in a garage located at the ground level of an old residential building constructed in Hong Kong was reported in 2015. Part of the building structures was damaged with the owners staying inside killed. The cause of explosion is still under investigation, but the explosion source can be due to leaking of LPG fuel or flammable clean refrigerants with LPG. A taxi has over 0.5 kg of refrigerant HFC134a (R134a) stored in the air-conditioning unit. A pressure rise exceeding 21 kPa (or 0.21 bar) due to explosion from a small amount of LPG would give damages to the building. As firefighters are always exposing themselves to the risk of explosion when they are carrying out rescue operation in a gas-filled environment, the explosion overpressure has to be more reliably estimated for working out protection schemes during operation. This garage LPG explosion incident was studied numerically using Computational Fluid Dynamics software FLame ACceleration Simulation (FLACS). Three scenarios of different LPG-air mixture volumes and LPG concentrations were investigated. Dispersion of LPG was simulated first with an ignition taken at a position at the garage centre. Overpressure and temperature rise were predicted using a fine grid system with 1 657 600 computing cells was employed. Results were compared with numerical predictions using coarse grids of 207 200 cells. Discussion and conclusions were made with reference to the threshold value of 21 kPa in overpressure. [ABSTRACT FROM AUTHOR]

Purpose: Adult slow-transit constipation (STC) occurs predominantly in females and is associated with low numbers of substance P (SP)-containing nerves in colonic circular muscle.Aim: To determine if reduced SP nerves is female predominant in paediatric STC.Methods: Children with STC were identified from records of more than 600 nuclear transit studies (NTS) and intestinal biopsies done for intractable chronic constipation between November 1998 and March 2009. Colonic seromuscular biopsies collected from hepatic and splenic flexures, and sigmoid colon were processed for immunohistochemistry. Nerve fibre density in circular muscle containing SP was measured qualitatively by a pathologist.Results: Eighty-eight children with chronic constipation had both NTS and intestinal biopsies. Seventy-eight children (52 M; age 2-15.5 years; mean 7.7 years) had STC diagnosed by NTS. SP was reduced in 10/26 girls, but only 11/52 boys.Conclusion: In this sample, STC was more common in boys than girls. However, in girls with STC, SP deficiency occurred in 40%, when compared with 20% of boys. During puberty, the percentage of girls with reduced SP decreased, whilst the percentage of boys increased. These results suggest that STC is heterogeneous and that there are some gender differences, the implication of which requires further investigation. [ABSTRACT FROM AUTHOR]

Using a single optical filter to demultiplex the all-optical orthogonal frequency-division multiplexing (OFDM) system was regarded as cost-effective and simple. Here, an all-optical OFDM signal demultiplexer using sinc transfer function was analyzed. The performance difference for using optical demultiplexers with different transfer functions was also compared and discussed. Within 20 km transmission, the sinc optical filter providing orthogonality between neighbor optical subcarriers can improve the signal performance by reducing the inter-carrier interference. After 20 km transmission, the signal performance degradation may mainly be dominated by dispersion for 10 Gb/s channel capacity; hence the advantage of sinc filter becomes negligible. These analyses provide the idea for how to choose the optical demultiplexer to integrate the whole optical fast Fourier transform circuit and optical sampling circuit into a single filter. This can effectively reduce the system cost and complexity. [ABSTRACT FROM AUTHOR]

In this demonstration, we first propose an optimal analogue front end circuit without employing pre-equalization (series peaking) to increase the modulation bandwidth of phosphor-LED in visible light communication (VLC) transmission. And there is no blue filter and post-equalization in the client side. Here, only using optimal adjustment of resistance (R), inductance (L), and capacitance (C) in bias-tee to compensate the impedance matching of phosphor-LED, nearly 32 MHz modulation bandwidth can be accomplished. Therefore, utilizing orthogonal frequency division multiplexed modulation with bit-loading algorithm in VLC system, 185 Mbps data rate can be achieved under a transmission distance of 80 cm. [ABSTRACT FROM AUTHOR]

The size of bronchial mucous glands in 21 patients who presented with meconium ileus and died at less than three weeks of age were compared quantitatively with that of 28 control patients. There were no significant differences by most methods of comparison. However, pulmonary infection was seen in a higher percentage of cystic fibrosis patients. The absence of mucous gland hyperplasia at birth suggests that mucous obstruction of airways may not be primarily responsible for the increased susceptibility to respiratory tract infection in cystic fibrosis, but when present later in life may aggravate the infection. [ABSTRACT FROM AUTHOR]

Peroxisomes were studied in the liver of two rhizomelic chondrodysplasia punctata patients using electron microscopy and catalase cytochemistry. Immunoelectron microscopy was carried out on the liver of one of these patients using antibodies to catalase, acyl-CoA oxidase, bifunctional protein, 3-ketoacyl-CoA thiolase and a 68 kDa peroxisomal membrane protein, in conjunction with protein-A colloidal gold. Moderately to markedly enlarged, flocculent peroxisomes were found in both patients. In one patient they were very heterogeneous with regard to the number per hepatocyte. The peroxisomes had very low levels of catalase as indicated by cytochemistry and immunocytochemistry. The three beta-oxidation enzymes were localised normally within the peroxisomes. The 68 kDa membrane protein was localised to the peroxisomal membranes. Some extra membrane loops were also identified using this antibody. [ABSTRACT FROM AUTHOR]

We propose and experimentally demonstrate a 37.3 Gb/s passive optical network using four-band orthogonal-frequency-division-multiplexing (OFDM) channels within 10 GHz bandwidth. Here, the required sampling rate and resolution of digital-to-analog/analog-to-digital (DA/AD) converter are only 5 GS/s and 8 bits to accomplish the 40 Gb/s OFDM downstream rate. Moreover, to reduce the power fading and fiber chromatic dispersion issues, a $$-$$ 0.7 chirp parameter Mach-Zehnder modulator is used for the four-band OFDM modulation scheme. Downstream negative power penalty of $$-$$ 0.37 dB can be obtained at the bit error rate of $$3.8\times 10^{-3}$$ after 20 km standard single mode fiber transmission without dispersion compensation. [ABSTRACT FROM AUTHOR]

In this investigation, we propose and investigate a wavelength converter by using a cost-effective and uncooled TO-can package reflective semiconductor optical amplifier with $$\sim $$ 1.2 GHz bandwidth. In this measurement, the converted data rate can support 1.25-10 Gbit/s on-off keying modulation rates by using the cross gain modulation technique. [ABSTRACT FROM AUTHOR]

We propose and demonstrate a new AC-light emitting diode based visible light communication system, in which the message signal is up-converted to 400 kHz frequency band and combine with the 60 Hz AC-power from the outlet. A special design bias-tee circuit is first implemented to combine the message signal and the AC-power for minimizing the signal distortion. Thus, the spectra of both signals are well separated. A special design clock recovery is used to synchronize the AC-power with the message signal; hence the message signal can be correctly applied to the rectified AC-power cycle. [ABSTRACT FROM AUTHOR]

PurposeThe purpose of this study was to measure macular sensitivity using microperimetry in patients on Plaquenil therapy without evidence of retinopathy as assessed by recommended screening standards.MethodsSixteen patients from a clinical practice treated with 200 or 400 mg/day of Plaquenil for more than 5 years, without visual complaints (visual acuity 20/25 or better), and without a history of diabetes or macular disease were included. Participants underwent a complete ophthalmic examination with spectral-domain optical coherence tomography (SD-OCT), 10-2 Humphrey visual field (HVF), fundus autofluoresecene (FAF), multifocal electroretinography (mfERG), and microperimetry that covered the central 12° of the visual field. Ten age-similar, visually normal subjects served as controls.ResultsThe average age of the study cohort was of 54.5 years, with an average daily Plaquenil dose of 4.00 mg/kg/day (range, 1.77-6.67 mg/kg/day) and an average cumulative dose of 1485 g (range, 256-3650 g). All patients had normal ocular exams, and no evidence of retinopathy based on 10-2 HVF, FAF, mfERG, and SD-OCT. The mean retinal sensitivity by microperimetry was 15.0 dB (OD) and 14.6 dB (OS). The overall mean microperimetry sensitivity of the patients (14.7±1.9 dB) was significantly lower (P<0.001) than that of the controls (16.5±2.1 dB).ConclusionsPatients on Plaquenil without clinical evidence of retinal toxicity can have reduced retinal sensitivity, as assessed by microperimetry. The mean sensitivity difference between the patients and controls suggests that microperimetry can provide important information regarding visual function in patients on Plaquenil therapy. [ABSTRACT FROM AUTHOR]

We propose and demonstrate a simple digital post-equalization technique to improve the bandwidth-limitation of light-emitting-diode (LED) visible-light-communication (VLC) channel. The design of finite-impulse-response equalizer according to the channel response is presented to improve the bandwidth limitation of LED VLC channel. Here, no optical blue filter is used. The simulation and experimental results show $$\sim $$ 10 times enhancement of the direct modulation speed of white-light LED VLC system. When compares with the previous demonstration using high-pass equalization circuit constructed by lumped capacitor and resistor, the proposed scheme shows an improvement in signal quality and transmission distance, and a 10 Mbit/s error-free free-space transmission over 1 m can be achieved under the bit error rate of $$< 10^{-9}$$ . [ABSTRACT FROM AUTHOR]

PurposeThe aim of this study is to report the short-term efficacy of aflibercept in the treatment of neovascular age-related macular degeneration (AMD) with associated retinal pigment epithelial detachment (PED) which is refractory or develops tachyphylaxis to bevacizumab and ranibizumab.MethodsThe method comprised a retrospective review of the medical records of patients with neovascular AMD and associated PEDs recently treated with aflibercept and previously treated with bevacizumab and ranibizumab.ResultsThree eyes of three female patients of ages 49, 55, and 65 years old with large serous PEDs and subretinal fluid (SRF) associated with occult choroidal neovascularization and neovascular AMD were treated with aflibercept after intravitreal bevacizumab and/or ranibizumab failed to resolve the lesions. All had complete resolution of SRF and complete or near-complete resolution of the PEDs after aflibercept injections over a 3-month period. Visual acuity improved in all three eyes.ConclusionIntravitreal aflibercept may be an effective treatment option for serous PED in neovascular AMD patients after bevacizumab and ranibizumab have previously failed. Larger studies with longer follow-up are required to determine the role of aflibercept in treatment of PED in neovascular AMD. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: An association between resting heart rate and mortality has been described in the general population and in patients with cardiovascular disease. There are, however, few data exploring this relationship in patients with type 2 diabetes mellitus. The current study addresses this issue. Methods: The relationship between baseline resting heart rate and all-cause mortality, cardiovascular death and major cardiovascular events (cardiovascular death, non-fatal myocardial infarction or non-fatal stroke) was examined in 11,140 patients who participated in the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) Study. Results: A higher resting heart rate was associated with a significantly increased risk of all-cause mortality (fully adjusted HR 1.15 per 10 bpm [95% CI 1.08, 1.21], p < 0.001), cardiovascular death and major cardiovascular outcomes without adjustment and after adjusting for age and sex and multiple covariates. The increased risk associated with a higher baseline resting heart rate was most obvious in patients with previous macrovascular complications (fully adjusted HR for death 1.79 for upper [mean 91 bpm] vs lowest [mean 58 bpm] fifth of resting heart rate in this subgroup [95% CI 1.28, 2.50], p = 0.001). Conclusions/interpretation: Among patients with type 2 diabetes, a higher resting heart rate is associated with an increased risk of death and cardiovascular complications. It remains unclear whether a higher heart rate directly mediates the increased risk or is a marker for other factors that determine a poor outcome. [ABSTRACT FROM AUTHOR]

RASSF1A is a key tumor-suppressor gene that is often inactivated in a wide variety of solid tumors. Studies have illustrated that RASSF1A plays vital roles in the regulation of cell-cycle progression and functions as a guardian of mitosis. Nevertheless, the precise mechanism of RASSF1A-dependent regulation of mitosis remains largely unclear. APC/CCdc20 is the master switch and regulator of mitosis. The activity of APC/CCdc20 is tightly controlled by phosphorylation and specific inhibitors to ensure the sequential ubiquitination of downstream targets. Here, we report on the novel finding of a regulated circuitry that controls the timely expression and hence activity of APC/CCdc20 during mitosis. Our study showed that RASSF1A and APC/CCdc20 form a molecular relay that regulates the APC/CCdc20 activity at early mitosis. We found that RASSF1A inhibits APC/CCdc20 function through its D-box motifs. Paradoxically, RASSF1A was also demonstrated to be ubiquitinated by APC/CCdc20 in vitro and degraded at prometaphase despite of active spindle checkpoint presence. The first two unique D-boxes at the N-terminal of RASSF1A served as specific degron recognized by APC/CCdc20. Importantly, we found that Aurora A and Aurora B directly phosphorylate RASSF1A, a critical step by which RASSF1A switches from being an inhibitor to a substrate of APC/CCdc20 during the course of mitotic progression. As a result of RASSF1A degradation, APC/CCdc20 can then partially activate the ubiquitination of Cyclin A in the presence of spindle checkpoint. This circuitry is essential for the timely degradation of Cyclin A. To conclude, our results propose a new model for RASSF1A-APC/CCdc20 interaction in ensuring the sequential progression of mitosis. [ABSTRACT FROM AUTHOR]

In this investigation we propose and experimentally demonstrate the self-protected and survivable time-division-multiplexed passive optical networks (PONs) in tree and ring topology architectures against fiber fault. Here, the feasible protection access architectures for the tree- and ring-based PONs are studied and discussed. Furthermore, different scenarios of fault locations, such as in the feeder fiber and distribution fiber, are also studied in the optical distributed networks. [ABSTRACT FROM AUTHOR]

ETV6-NTRK3 (EN), a chimeric tyrosine kinase generated by t(12;15) translocations, is a dominantly acting oncoprotein in diverse tumor types. We previously showed that insulin-like growth factor 1 receptor (IGF1R) is essential for EN-mediated oncogenesis and that insulin receptor substrate 1 (IRS1) is constitutively tyrosine phosphorylated and bound by EN in transformed cells. Given that IRS1 is also an adapter for IGF1R, we hypothesized that IRS1 might localize EN to IGF1R at the membrane to activate phosphatidylinositol 3-kinase (PI3K)-Akt, which is critical for EN oncogenesis. In this study, we examined EN/IRS1/IGF1R complexes in detail. We find that both IRS1 and kinase active IGF1R are required for EN transformation, that tyrosine phosphorylated IRS1 is present in high molecular weight complexes with EN and IGF1R, and that EN colocalizes with IGF1R at the plasma membrane. Both IGF1R kinase activity and an intact cytoplasmic Y950 residue, the IRS1-docking site of IGF1R, are required, confirming the importance of the IGF1R/IRS1 interaction for EN oncogenesis. The dual specificity IGF1R and insulin receptor (INSR) inhibitor, BMS-536924, blocks EN transformation activity, cell survival and its interaction with IRS proteins, and induces a striking shift of EN proteins to smaller sized molecular complexes. We conclude that a tripartite complex of EN, IRS1 and IGF1R localizes EN to the membrane and that this is essential for EN-mediated transformation. These findings provide an explanation for the observed IGF1R dependency of EN transformation. Blocking IGF1R kinase activity may, therefore, provide a tractable therapeutic strategy for the many tumor types driven by the EN oncoprotein. [ABSTRACT FROM AUTHOR]

Suppression of anoikis after detachment of cancer cells from the extracellular matrix is a key step during metastasis. Here we show that, after detachment, mouse embryonic fibroblasts (MEFs) transformed by K-Ras(V12) or ETV6-NTRK3 (EN) activate a transcriptional response overrepresented by genes related to bioenergetic stress and the AMP-activated protein kinase (AMPK) energy-sensing pathway. Accordingly, AMPK is activated in both transformed and non-transformed cells after detachment, and AMPK deficiency restores anoikis to transformed MEFs. However, AMPK activation represses the mTOR complex-1 (mTORC1) pathway only in transformed cells, suggesting a key role for AMPK-mediated mTORC1 inhibition in the suppression of anoikis. Consistent with this, AMPK−/− MEFs transformed by EN or K-Ras show sustained mTORC1 activation after detachment and fail to suppress anoikis. Transformed TSC1−/− MEFs, which are incapable of suppressing mTORC1, also undergo anoikis after detachment, which is reversed by mTORC1 inhibitors. Furthermore, transformed AMPK−/− and TSC1−/− MEFs both have higher total protein synthesis rates than wild-type controls, and translation inhibition using cycloheximide partially restores their anoikis resistance, indicating a mechanism whereby mTORC1 inhibition suppresses anoikis. Finally, breast carcinoma cell lines show similar detachment-induced AMPK/mTORC1 activation and restoration of anoikis by AMPK inhibition. Our data implicate AMPK-mediated mTORC1 inhibition and suppression of protein synthesis as a means for bioenergetic conservation during detachment, thus promoting anoikis resistance. [ABSTRACT FROM AUTHOR]

Both central obesity and increased carotid intima-media thickness (IMT) are markers of atherosclerosis and associated with cardiovascular diseases (CVD). Information of IMT in Chinese subjects with central obesity is limited. This study was performed to assess the rate of atherosclerosis and abnormal IMT in asymptomatic Chinese subjects with central obesity, and to investigate the association between IMT values and CVD risk factors including hypertension, hyperglycaemia and dyslipidaemia. We studied 122 centrally obese adults who had good past health. IMT measurements on carotid arteries were performed and fasting blood taken for plasma glucose and lipid profiles. Abnormal IMT was defined as > 0.9 mm. Atherosclerosis was defined as the presence of one or more visible plague. Of the 122 subjects, the mean (±SD) age was 59.4 ± 5.8 years (median [range]: 59.0 [45-75] years). The median IMT value was 0.70 mm (range: 0.53-1.19 mm) [men vs. women: 0.74 mm vs. 0.66 mm, P-value: < 0.001]. IMT values and the rate of atherosclerosis increased with age and the number of CVD risk factors ( P-value for trend: < 0.05). Using binary logistic regression to predict the presence of atherosclerosis with the presence of abnormal IMT, age, gender, and other CVD risk factors as independent variables, age (OR [95% CI] = 1.13 [1.03, 1.23], P = 0.009) and abnormal IMT (OR [95% CI] = 4.05 [1.09, 15.03], P = 0.037) were independently associated with atherosclerosis. In conclusion, among Hong Kong Chinese asymptomatic subjects with central obesity, there was a high rate of CVD risk factors. We found that 19% of these subjects had carotid atherosclerotic plaques and 10% of them had abnormal IMT (>0.9 mm). Carotid IMT study may serve as an appropriate screening tool to diagnose atherosclerosis in the centrally obese middle-aged population. [ABSTRACT FROM AUTHOR]

Background/Objectives:Excessive consumption of sugar-sweetened beverages (SSBs) increases risk of obesity. Similar data are lacking in Chinese populations with rapid nutritional transition. We aimed to examine the association between SSB intake, lifestyle factors and obesity in Hong Kong Chinese.Subjects/Methods:This is a cross-sectional survey on SSB intake with 2295 (49.6%) men and 2334 (50.4%) women (age: median 43.0 years, range 18-81 years). They were recruited from a territory-wide health promotion campaign in Hong Kong. All subjects completed a questionnaire and underwent simple health tests. Their SSB intake was based on a 1-week recall (1 unit of SSB=250 ml, frequent SSB consumption=daily intake2 units).Results:Men were more likely than women to smoke, drink alcohol, frequently consumed SSB (20.5 vs 9.5%) and ate more meat portions (2.32±0.57 vs 2.15±0.44) but were physically more active (no exercise: 31.2 vs 39.2%) (P-values: all <0.001). After adjusting for confounding factors, frequent SSB intake remained independently associated with obesity in women (odds ratio (95% confidence interval): 1.86 (1.36-2.55)) while physical inactivity (1.84 (1.41-2.39) for none vs regular), smoking (1.29 (1.05-1.58)) and high daily meat intake (2.15 (1.36, 3.42)) predicted obesity in men.Conclusions:In Chinese of working age, SSB consumption in women and physical inactivity, smoking and high meat intake in men were associated with obesity. [ABSTRACT FROM AUTHOR]

This paper aims at presenting an experimental investigation of the mechanical properties of the weldment in titanium tailor-welded blanks (Ti-TWBs) at different elevated temperatures. High-contrast image patterns were laser-marked on the surface of Ti-TWB weldment. During the transverse tensile test of Ti-TWB, the images of weldment deformations and their corresponding applied loads were captured simultaneously by a dual-image vision system. After the image processing, the true stress–strain data of the weldment were evaluated successfully. Also, the stress–strain behaviors of the weldment for Ti-TWBs at different elevated temperatures were measured by heating up the specimens to specified temperatures (300°C, 500°C, and 600°C) using an induction coil specially connected to the induction furnace. Finally, the results show that, similar to the "as received" titanium sheets, increase in temperature enhances the ductility of the weldment favorably, thus reducing the required load for the related metal working. [ABSTRACT FROM AUTHOR]

Objective: To elucidate the mathematical relationship between longitudinal changes of body composition and the adaptations of substrate utilization required to produce those changes.Design: We developed a simple mathematical model of macronutrient balance. By using an empirical relationship describing lean body mass as a function of fat mass, we derived a mathematical expression for how substrate utilization adapts to changes of diet, energy expenditure and body fat such that energy imbalances produced the required changes of body composition.Results: The general properties of our model implied that short-term changes of dietary fat alone had little impact on either fat or non-fat oxidation rates, in agreement with indirect calorimetry data. In contrast, changes of non-fat intake caused robust adaptations of both fat and non-fat oxidation rates. Without fitting any model parameters, the predicted body composition changes and oxidation rates agreed with experimental studies of overfeeding and underfeeding when the measured food intake, energy expenditure and initial body composition were used as model inputs.Conclusion: This is the first report to define the quantitative connection between longitudinal changes of body composition and the required relationship between substrate utilization, diet, energy expenditure and body fat mass. The mathematical model predictions are in good agreement with experimental data and provide the basis for future study of how changes of substrate utilization impact body composition regulation. [ABSTRACT FROM AUTHOR]

Tailor-welded Blanks (TWBs) are tailor-made for different complex component designs by welding multiple metal sheets with different thicknesses, shapes or strengths prior to forming. However, the forming performance of an intrinsic TWB is critically related to its own structures and designs, such as the thickness combination, as well as the location and orientation of weldment. In this study, a 2 kW Nd:YAG laser were used to butt-weld approximately 180 samples of stainless steel (AISI 304) TWBs with different dimensions (i.e., from 12.7 mm to 165.1 mm in width), thickness combinations (i.e., 1.0/1.0 mm, 1.0/1.2 mm, 1.0/1.5 mm, 1.2/1.2 mm, 1.2/1.5 mm and 1.5/1.5 mm) and welding orientations (i.e., 0°, 45° and 90°). Subsequently, Swift forming tests were carried out to characterize the forming performance of those TWBs. Obviously, the optimal sets of welding parameters relating critically to the quality of weld was a primary criterion for the formability test of TWBs in this study. The effects of different thickness combinations on the formability of TWBs were investigated through the constructed forming limit diagrams (FLDs). The results showed that the thinner part of TWBs dominated the majority of deformation similar to the FLD of the parent metal. The effects of different welding orientations on the forming performance of TWBs were examined from the failure analysis. [ABSTRACT FROM AUTHOR]

Issues related to empirical dietary restriction are important, but they have been inadequately studied among children with atopic dermatitis (AD). To evaluate whether any association exists between food atopy, food avoidance, and AD severity, investigators in the present study reviewed all skin prick tests (SPTs) performed between January 2005 and April 2006 at a pediatric dermatology clinic and correlated findings with history of food avoidance and eczema severity. Only 13% of 114 children with AD had a positive SPT for beef. The most commonly sensitized foods were egg yolk (53%), egg white (42%), shrimp (35%), peanuts (31%), and crab (29%). Disease severity was not associated with prevalence of sensitization to these foods. The investigators concluded that immediate immunoglobulin E reaction to beef, as suggested by positive SPT findings, is unlikely to occur in most children with AD. SPT information may be useful in reassuring parents about the unlikelihood of a severe and immediate reaction to beef. As for other foods, it is sensible to advise parents about specific avoidance strategies only in more severely affected children with a definite history of eczema exacerbation by specific food allergens. [ABSTRACT FROM AUTHOR]

This study was undertaken to evaluate the clinical efficacy of tacrolimus for itch reduction in children with atopic dermatitis (AD). Seven children (3 boys and 4 girls) with AD were treated with topical tacrolimus for a consecutive 2-wk period after a 1-wk run-in. The clinical severity of AD was assessed with the SCORing Atopic Dermatitis (SCORAD) scale. Sleep disturbance, as reported by patients, and nocturnal scratching documented by a wrist movement monitor (DigiTrac), were evaluated at baseline and throughout treatment. The median (interquartile range) objective SCORAD scores before and after treatment were 27.2 (24.8-36.7) and 23.9 (22.6-36.5), respectively (P=.248). Overall SCORAD scores before and after treatment were 36.1 (32.8-45.7) and 29.4 (24.8-45.4), respectively (P=.05). Scores on the itch and sleep disturbance components of the SCORAD were reduced from 5.0 (5.0-6.5) and 4.0 (3.5-5.0) to 4.0 (2.0-5.0) and 3.0 (0.5-4.5), respectively. Total SCORAD was reduced in 6 patients (range, 8%-36% reduction) and remained similar in 1 patient. No significant change in the area or intensity component of the SCORAD was detected 14 d after treatment began (P=.48 and P=.115, respectively). Scratching activity, as documented by the DigiTrac movement recorder, was reduced from 115.0 g/min (64.8-215.5) to 71.5 g/min (51.0-118.0) (P=.028) after 2 wk of treatment. Daily symptom scores (n=6 pairs) for sleep disturbance reported separately each day by patients and parents correlated strongly with each other (intraclass coefficient, 0.60-0.98). The findings of this study show that tacrolimus is effective in relieving itch in children with AD. Investigators suggest that scratching movements, objectively measured with the use of DigiTrac, provide a reliable indicator of AD severity in children. [ABSTRACT FROM AUTHOR]

The objective of the study was to investigate risk factors and develop risk equations for end-stage renal disease (ESRD) in Chinese patients with type 2 diabetes. A prospective cohort of 4,438 patients with type 2 diabetes mellitus and without ESRD (median observation period 2.9 years, interquartile range 1.6–4.1 years) was included in the analysis. The end-point (ESRD) was defined by: (1) death due to diabetes with renal manifestations or renal failure; (2) hospitalisation due to renal failure; (3) estimated GFR (eGFR) <15 ml min−1 1.73 m−2. Cox proportional hazards regression was used to develop risk equations. The data were randomly and evenly divided into the training data for development of the risk equations and the test data for validation. The validation was performed using the area under the receiver operating characteristic curve (aROC), which takes into account follow-up time and censoring. During the observation period, 159 patients or 12.45 per 1,000 person-years (95% CI 10.52–14.37 per 1,000 person-years) developed ESRD. Known duration of diabetes, systolic blood pressure, log10 total cholesterol:HDL cholesterol ratio and retinopathy were significant predictors of ESRD. After further adjusting for eGFR, log10 spot albumin:creatinine ratio (ACR) and haematocrit, only eGFR, haematocrit and log10 ACR remained as independent predictors of ESRD. The risk equation derived from these three independent predictors had good discrimination, with an aROC of 0.97. Estimated GFR, haematocrit and ACR were independent predictors of ESRD and the derived risk equation performed well in Chinese patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Hypoxia and exercise each modulate muscle Na(+), K(+)ATPase activity. We investigated the effects on muscle Na(+), K(+)ATPase activity of only 5 nights of live high, train low hypoxia (LHTL), 20 nights consecutive (LHTLc) versus intermittent LHTL (LHTLi), and acute sprint exercise. Thirty-three athletes were assigned to control (CON, n = 11), 20-nights LHTLc (n = 12) or 20-nights LHTLi (4 x 5-nights LHTL interspersed with 2-nights CON, n = 10) groups. LHTLc and LHTLi slept at a simulated altitude of 2,650 m (F(I)O(2) 0.1627) and lived and trained by day under normoxic conditions; CON lived, trained, and slept in normoxia. A quadriceps muscle biopsy was taken at rest and immediately after standardised sprint exercise, before (Pre) and after 5-nights (d5) and 20-nights (Post) LHTL interventions and analysed for Na(+), K(+)ATPase maximal activity (3-O-MFPase) and content ([(3)H]-ouabain binding). After only 5-nights LHTLc, muscle 3-O-MFPase activity declined by 2% (P < 0.05). In LHTLc, 3-O-MFPase activity remained below Pre after 20 nights. In contrast, in LHTLi, this small initial decrease was reversed after 20 nights, with restoration of 3-O-MFPase activity to Pre-intervention levels. Plasma [K(+)] was unaltered by any LHTL. After acute sprint exercise 3-O-MFPase activity was reduced (12.9 +/- 4.0%, P < 0.05), but [(3)H]-ouabain binding was unchanged. In conclusion, maximal Na(+), K(+)ATPase activity declined after only 5-nights LHTL, but the inclusion of additional interspersed normoxic nights reversed this effect, despite athletes receiving the same amount of hypoxic exposure. There were no effects of consecutive or intermittent nightly LHTL on the acute decrease in Na(+), K(+)ATPase activity with sprint exercise effects or on plasma [K(+)] during exercise. [ABSTRACT FROM AUTHOR]

How are metalinguistic skills associated with vocabulary knowledge in languages with contrasting phonological and morphological properties? To address this question, tasks of phonological awareness and morphological awareness, other reasoning and literacy-related skills, and measures of vocabulary knowledge in Chinese and English, were administered to 217 Hong Kong Chinese kindergarten children learning English as a second language. Syllable-level awareness but not phoneme onset awareness was strongly associated with Chinese vocabulary knowledge; phoneme onset awareness but not syllable awareness was associated with English vocabulary knowledge. In hierarchical regression equations, phonological awareness in English explained unique variance in English vocabulary knowledge but not in Chinese vocabulary knowledge. In contrast, measures of morphological awareness, which were strongly associated with syllable awareness, uniquely explained 13% of the variance in Chinese vocabulary knowledge apart from all other measures included but were not uniquely associated with English vocabulary knowledge. Findings highlight the strong overlap across phonological and morphological awareness in Chinese and the different associations of each to vocabulary acquisition in Chinese (L1) and English (L2) languages. [ABSTRACT FROM AUTHOR]

Hypoxia and exercise each modulate muscle Na+, K+ATPase activity. We investigated the effects on muscle Na+, K+ATPase activity of only 5 nights of live high, train low hypoxia (LHTL), 20 nights consecutive (LHTLc) versus intermittent LHTL (LHTLi), and acute sprint exercise. Thirty-three athletes were assigned to control (CON, n = 11), 20-nights LHTLc ( n = 12) or 20-nights LHTLi (4 × 5-nights LHTL interspersed with 2-nights CON, n = 10) groups. LHTLc and LHTLi slept at a simulated altitude of 2,650 m (FIO2 0.1627) and lived and trained by day under normoxic conditions; CON lived, trained, and slept in normoxia. A quadriceps muscle biopsy was taken at rest and immediately after standardised sprint exercise, before (Pre) and after 5-nights (d5) and 20-nights (Post) LHTL interventions and analysed for Na+, K+ATPase maximal activity (3- O-MFPase) and content ([3H]-ouabain binding). After only 5-nights LHTLc, muscle 3- O-MFPase activity declined by 2% ( P < 0.05). In LHTLc, 3- O-MFPase activity remained below Pre after 20 nights. In contrast, in LHTLi, this small initial decrease was reversed after 20 nights, with restoration of 3- O-MFPase activity to Pre-intervention levels. Plasma [K+] was unaltered by any LHTL. After acute sprint exercise 3- O-MFPase activity was reduced (12.9 ± 4.0%, P < 0.05), but [3H]-ouabain binding was unchanged. In conclusion, maximal Na+, K+ATPase activity declined after only 5-nights LHTL, but the inclusion of additional interspersed normoxic nights reversed this effect, despite athletes receiving the same amount of hypoxic exposure. There were no effects of consecutive or intermittent nightly LHTL on the acute decrease in Na+, K+ATPase activity with sprint exercise effects or on plasma [K+] during exercise. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: We examined the association between chronic hepatitis B virus (HBV) infection and clinical outcomes in a consecutive cohort of Chinese patients with type 2 diabetes. Subjects, materials and methods: Between 1995 and 1999, 2,838 type 2 diabetes patients underwent comprehensive assessments and blood screening for hepatitis B surface antigen (HBsAg). The risk of occurrence of cardiovascular events and end-stage renal disease (defined as need for dialysis, doubling of serum creatinine or serum creatinine ≥500 µmol/l) was compared between HBsAg-positive and HBsAg-negative groups. Results: At baseline, HBV-infected patients (n=286, 10.1%) were younger (51.0±11.5 vs 53.7±12.7 years, p=0.004), had earlier onset of diabetes (51.0±11.5 vs 53.7±12.7 years, p=0.001) and a higher frequency of retinopathy (28 vs 22%, p=0.03) than non-HBV-infected patients. After a median follow-up of 3.5 years (interquartile range: 1.7.5.9 years) and adjustment of age, glycaemic control and other potential confounding factors, HBV-infected patients were more likely to develop end-stage renal disease than non-HBV infected patients (8.7 vs 6.4%) with a hazard ratio of 4.5 (95% CI 1.1.18.6). The difference in the frequency of cardiovascular endpoints was not statistically significant. Conclusions: In Chinese type 2 diabetes patients, chronic HBV infection was associated with increased risk of end-stage renal disease, and this was independent of other potential confounding factors. Early identification of HBV status and close surveillance of renal function are important in patients with type 2 diabetes who are living in areas where HBV is endemic or who are at risk of chronic HBV infection. [ABSTRACT FROM AUTHOR]

A microscopic investigation has been made on the shearing of one leaded and two lead-free solders by using anin situSEM method. A shear lap joint specimen is designed and fabricated to accommodate a thin layer of solder alloy between copper strips. A non-contact method that measures strains in a very narrow area in the solder was applied. A laser grid was also used on the copper strip for measuring the back-face strain. Simultaneously micrographs at various stages were also taken. Wherein situmeasurements and micrographs are recorded they can reveal the continual development of damage and fracture mechanisms consistent with observations generated by low-cycle fatigue loading. This means that the shear test can be used as an alternative test to fatigue loading tests. By comparison, two lead-free solder specimens showed much smaller elongation to failure than the leaded solder, although all specimens showed similar sequence of events leading to final failure, including the boundary layer fracture phenomenon. The back-face strain indicator for the formation of a macro crack is due to the shifting of high stress concentration area from the joint-edge region to outside the joint region as revealed by a damage-coupled finite element procedure. The procedure also provides an estimate on the critical back-face strain. [ABSTRACT FROM AUTHOR]

Spin coating is a simple process for rapidly depositing thin, solid polymeric films onto relatively flat substrates. Evaporation occurs during spinning of the relatively volatile species in any solution. The curing behavior of spin-coated polymeric film is influenced by the evaporation of any reactive component. An investigation was carried out on a silicon substrate to study the effects of spin coating on the curing behavior of the epoxy adhesive. The degree of curing for both spin and without spin-coated epoxy adhesive was measured by Fourier-transform infrared spectroscopy (FTIR). A slower curing reaction rate was observed for the spin-coated epoxy adhesive. The composition gradient established by solvent evaporation during spinning is responsible for the slower curing reaction rate of the spin-coated epoxy adhesive. From this study, it is proposed to use solvents that are less volatile and allow a greater part of the thinning behavior to occur without significant changes in the fluid properties during the spinning process. [ABSTRACT FROM AUTHOR]

Focuses on gene expression within replicating episomal plasmid and cosmid vectors. Locus control region; transcriptional regulatory elements; Chromatin remodeling and transcription; Epstein-Barr virus-based plasmid replicating episomal vectors.

Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are two related conditions caused by mutations of the Wilms tumor gene, WT1. Both syndromes are characterized by male pseudohermaphroditism, a progressive glomerulopathy, and the development of genitourinary tumors. DDS and FS have previously been distinguished by differences in nephropathy, with DDS patients demonstrating diffuse mesangial sclerosis (DMS) in contrast to focal and segmental glomerulosclerosis (FSGS) in FS patients. The clinicopathological features and genotype analysis of two patients with WT1 mutations are presented in this report. Genotype analysis of the first patient revealed a previously undescribed mutation in exon 8 of the WT1 gene. The second patient presented with a rapidly progressive nephropathy characterized histologically by DMS, but was found to have the genetic mutation seen in FS patients. A summary of all reported patients with the characteristic mutation associated with FS demonstrates the clinical overlap of this syndrome with DDS. This suggests that both these conditions should be considered as part of the spectrum of disease due to WT1 gene mutations rather than as separate diseases. Clinical classification remains important for prognosis, as the underlying renal disease appears to predict the progression of nephropathy independently of the genetic abnormality. [ABSTRACT FROM AUTHOR]

In the small intestine of both embryonic birds and mammals, neuron precursors aggregrate first at the site of the myenteric plexus, and the submucous plexus develops later. However, in the large intestine of birds, the submucosal region is colonised by neural-crest-derived cells before the myenteric region (Burns and Le Douarin, Development 125:4335–4347, 1998). Using antisera that recognize undifferentiated neural-crest-derived cells (p75NTR) and differentiated neurons (PGP9.5), we examined the colonisation of the murine large intestine by neural-crest-derived cells and the development of the myenteric and submucosal plexuses. At E12.5, when the neural crest cells were migrating through and colonising the hindgut, the hindgut mesenchyme was largely undifferentiated, and a circular muscle layer could not be discerned. Neural-crest-derived cells migrated through, and settled in, the outer half of the mesenchyme. By E14.5, neural-crest-derived cells had colonised the entire hindgut; at this stage the circular muscle layer had started to differentiate. From E14.5 to E16.5, p75NTR- and PGP9.5-positive cells were observed on the serosal side of the circular muscle, in the myenteric region, but not in the submucosal region. Scattered, single neurons were first observed in the submucosal region around E18.5, and groups of neurons forming ganglia were not observed until after birth. The development of the enteric plexuses in the murine large intestine therefore differs from that in the avian large intestine. [ABSTRACT FROM AUTHOR]

Renal and hepatic sonography were performed in 2 neonates with glomerulocystic renal disease. One neonate had ultrasound findings of normal hypoechoic medullary pyramids, enabling differentiation from infantile polycystic renal disease. Previous case reports have highlighted the similarity of renal ultrasound findings in these two conditions. [ABSTRACT FROM AUTHOR]

Confocal fluorescence microscopy enables visualisation and quantitation of fluorescent probes at high resolution deep within intact tissues, with minimal disturbance both of cell–cell interactions and the mechanical, ionic and physiological effects of the extracellular matrix. We illustrate the principles of multiple-parameter 3-D ( x, y, z) imaging using reconstruction of nuclear channels in mammalian cells. Repeated sampling in time generates 4-D ( x, y, z, t) images which can be used to follow dynamic changes, such as blue-light-dependent chloroplast re-orientation, in intact tissues. Quantitative measurements from multi-dimensional images require calibration of the spatial dimensions of the image and the fluorescence intensity response. This must be determined throughout the volume, which must be sampled to correct for geometric distortion as well as photometric errors arising from the complete optical system, including the specimen. The effects of specimen calibration are illustrated for morphological analysis of stomatal closing responses to abscisic acid in Commelina from 4-D images. Calibrated 4-D imaging allows direct volume measurements and we have followed volume regulation of chondrocytes in cartilage explants during osmotic perturbation. In intact cartilage, unlike in isolated cells, the chondrocytes exhibit volume regulatory mechanisms. In other cases, the fluorescence intensity of the probe may be related to a physiological parameter of interest and changes in its distribution within the cell. Optical sectioning permits discrimination of signal in separate compartments within the cell and can be used to follow transport events between different organelles. We illustrate 3-D ( x, y, t) measurements of vacuolar glutathione conjugate pump activity in intact roots of Arabidopsis by following the sequestration of a fluorescent conjugate between glutathione and monochlorobimane. Dynamic measurements of protein localisation are now possible following the introduction of chimeric fusion proteins with green fluorescent protein (GFP) from Aequoria victoria. We have analysed the disposition of heterochromatin in nuclei of living Schizosaccharomyces pombe cells expressing a chimeric construct between Swi6 and GFP. Heterochromatin dynamics can be followed throughout mitosis in 4-D ( x, y, z, t) images. Statistical analysis of the fluorescence histograms from each nucleus over time provides quantitative support for aggregation and dispersion of Swi6-GFP clusters during mitosis, rather than dissociation of Swi6 from the heterochromatin. A wide range of single-wavelength and ratio probes are available for imaging different ion activities. We compare 3-D ( x, y, t) measurements of ion activities made using single-wavelength (Fluo-3 for calcium) and ratio (BCECF for pH) measurements, using stomatal responses in Vicia faba to peptides from the auxin-binding protein of maize and tip growth in pollen tubes of Lilium longiflorum as examples. Ratioing techniques have many advantages for quantitative fluorescence measurements and we conclude with a discussion of techniques to develop ratioing of single-wavelength probes against alternative references, such as DNA, protein or cell wall material. [ABSTRACT FROM AUTHOR]

In children with severe chronic constipation, abnormal distribution of substance P (SP) and vasoactive intestinal peptide (VIP), which represent excitatory and inhibitory nerves, respectively, has been reported. The normal distribution of these neuropeptides, however, is not well known. The aim of this study was to determine the populations of SP- and VIP-immunoreactive nerve fibres in the circular muscle of the colon in children. Surgically resected specimens were collected from a 6-year-old girl with familial polyposis coli (total colon) and nine patients with anorectal malformations aged 0–4 years (sigmoid colon). Double-labelling immunofluorescence was employed using neuron-specific enolase (NSE) with SP and NSE with VIP to count the percentage of SP- or VIP-labelled nerve fibres. These specimens showed normal submucous and myenteric plexuses stained with NSE. The population of SP- immunoreactive fibres was 15%–21% throughout the colon, and VIP was 39% in the caecum and 63%–65% in the transverse, descending, and sigmoid colon. In the four neonatal specimens (day 1 to 4), the SP population was only 1%–6% and the VIP population was also low (22%–33%). After 3 weeks of age, the populations had stabilised at 18%–26% for SP and 52%–62% for VIP. SP-immunoreactive nerve fibres were scarce in the neonatal period, and showed a rapid increase by 3 weeks and a similar though less dramatic increase in VIP-immunoreactive fibres. VIP-immunoreactive fibres were fewer in the caecum that at other colonic levels, where they accounted for 60% of NSE-labelled fibres; the SP population, however, was comparable at all levels of the colon at about 20% of NSE-labelled fibres. [ABSTRACT FROM AUTHOR]