In Functional magnetic resonance imaging (fMRI), the blood oxygen level dependent (BOLD) signal is modeled as a convolution of the hemodynamic response function (HRF) and the unmeasured latent neural signal. Although most cortical and subcortical brain regions share the canonical shape of the HRF, the temporal structure of HRFs are variable across brain regions and subjects. This variability is induced by both neural and non-neural factors. The variability between subjects can be examined by three parameters that characterize the HRF: response height (RH), time-to-peak (TTP) and full-width at half-max (FWHM). This data provides three HRF parameters at every voxel, obtained from Autism Spectrum Disorder (ASD) patients (N = 531), and matched healthy controls (N = 571). Since ongoing studies suggest that non-standard populations have important differences in their HRFs when compared with healthy control, this data set is valuable in studying variability of HRF in ASD group and inferring the underlying pathology that also affects the HRF. It also has implications for fMRI analyses like resting-sate connectivity analysis.

OBJECTIVE

To evaluate oxygenation changes in rat subcutaneous C6 gliomas using blood-oxygen-level dependent (BOLD) functional magnetic resonance imaging (fMRI) combined with non-haemodynamic response function (non-HRF) analysis.

METHODS

BOLD fMRI were performed during carbogen inhalation in 20 Wistar rats bearing gliomas. Statistical maps of spatial oxygenation changes were computed by a dedicated non-HRF analysis algorithm. Three types of regions of interest (ROIs) were defined: (1) maximum re-oxygenation zone (ROImax), (2) re-oxygenation zones that were less than the maximum re-oxygenation (ROInon-max), and (3) zones without significant re-oxygenation (ROInone). The values of percent BOLD signal change (PSC), percent enhancement (ΔSI), and significant re-oxygenation (T) were extracted from each ROI. Tumours were sectioned for histology using the fMRI scan orientation and were stained with haematoxylin and eosin and CD105. The number of microvessels (MVN) in each ROI was counted. Differences and correlations among the values for T, PSC, ΔSI, and MVN were determined.

RESULTS

After carbogen inhalation, the PSC significantly increased in the ROImax areas (p<0.01) located in the tumour parenchyma. No changes occurred in any of the ROInone areas (20/20). Some changes occurred in a minority of the ROInon-max areas (3/60) corresponding to tumour necrosis. MVN and PSC (R=0.59, p=0.01) were significantly correlated in the ROImax areas. In the ROInon-max areas, MVN was significantly correlated with PSC (R=0.55, p=0.00) and ΔSI (R=0.37, p=0.00).

CONCLUSIONS

Statistical maps obtained via BOLD fMRI with non-HRF analysis can assess the re-oxygenation of gliomas.

Functional magnetic resonance imaging (fMRI) is an indirect measure of brain activity, i.e. it is a convolution of the latent (unmeasured) neural signal and the hemodynamic response function (HRF). As such, the HRF has been shown to vary across brain regions and individuals. The shape of the HRF is controlled by both neural and non-neural factors. The shape of the HRF can be characterized by three parameters (response height, time-to-peak and full-width at half-max). The data presented here provides the three HRF parameters at every voxel, obtained from U.S. Army soldiers (N=87) diagnosed with posttraumatic stress disorder (PTSD), with comorbid PTSD and mild-traumatic brain injury (mTBI), and matched healthy combat controls. Findings from this data and further interpretations are available in our recent research study (Rangaprakash et al., 2017) [1]. This data is a valuable asset in studying the impact of HRF variability on fMRI data analysis, specifically resting state functional connectivity.

This study identified three critical housing-related factors (HRFs) as moderators of the relationships between employees' psychological capital (PsyCap) and job embeddedness (JE) in China's entrepreneurial environment. The hypotheses were tested with multiple hierarchical regression modeling, using the data collected from 312 employees in manufacturing organizations. The results demonstrated that HRFs (i.e., home ownership, housing price satisfaction, and contributions to housing funds) moderate the relationships between employees' PsyCap and JE. Specifically, these relationships were stronger when the HRFs were high. Such results contribute to the PsyCap and JE literature by incorporating housing as an extrinsic life-aspect factor that might affect employees' psychological state and thus their retention in works. Implications for the organization policies and directions for future studies were discussed.

OBJECTIVE

To assess the macular retinal and choroidal microcirculation blood flow in patients with exudative age related macular degeneration before and after photodynamic therapy (PDT) or transpupillary thermotherapy (TTT) with Doppler laser scanning (HRF--Heidelberg retinal flowmeter).

METHODS

Thirty patients with exudative age-related macular degeneration were included in a prospective study. The diagnosis was established based on ophthalmic examination and fluorescein angiography results. In all cases the subfoveal choroidal neovascularization (CNV) was present. Control group consists of the fellow eyes with early stage of AMD (19 eyes) or with disciform scar (11 eyes). In 15 eyes with active CNV PDT was performed and in remaining 15--TTT. In all cases the macular blood flow was measured with Heidelberg retina flowmeter (HRF) before therapy and then 1 week, 4 weeks and 10-12 weeks after treatment.

RESULTS

At the baseline examination in a group of eyes with active CNV the mean values of macular blood flow were significantly higher comparing to the fellow eyes and reached respectively: 678.6 +/- 125.0 AU and 298.4 +/- 79.2 AU (p=0.001). Four weeks after treatment all eyes showed the reduction of macular blood flow comparing to the baseline values (p=0.001). Ten to twelve weeks after laser therapy in all cases the increased macular blood flow was detected comparing to the previous examination (p=0.01). During the follow-up period the macular blood flow in the fellow eyes were significantly lower than in treated eyes.

CONCLUSIONS

The measurement of macular blood flow using Doppler scanning laser (HRF--Heidelberg retinal flowmeter) may act as a non-invasive and useful diagnostic tool in assessment of CNV activity in patients with exudative age-related degeneration before and after PDT or TTT.

Inter-subject parcellation of functional Magnetic Resonance Imaging (fMRI) data based on a standard General Linear Model (GLM) and spectral clustering was recently proposed as a means to alleviate the issues associated with spatial normalization in fMRI. However, for all its appeal, a GLM-based parcellation approach introduces its own biases, in the form of a priori knowledge about the shape of Hemodynamic Response Function (HRF) and task-related signal changes, or about the subject behaviour during the task. In this paper, we introduce a data-driven version of the spectral clustering parcellation, based on Independent Component Analysis (ICA) and Partial Least Squares (PLS) instead of the GLM. First, a number of independent components are automatically selected. Seed voxels are then obtained from the associated ICA maps and we compute the PLS latent variables between the fMRI signal of the seed voxels (which covers regional variations of the HRF) and the principal components of the signal across all voxels. Finally, we parcellate all subjects data with a spectral clustering of the PLS latent variables. We present results of the application of the proposed method on both single-subject and multi-subject fMRI datasets. Preliminary experimental results, evaluated with intra-parcel variance of GLM t-values and PLS derived t-values, indicate that this data-driven approach offers improvement in terms of parcellation accuracy over GLM based techniques.

The speculation that human histamine releasing factor (HRF) - a lymphokine that releases histamine from human tissues, might be the same as gamma-interferon was investigated. The speculation arose from the fact that HRF and gamma-interferons are both lymphokines and have both been reported to affect histamine release from human basophils. Using purified gamma-interferons either naturally obtained or E. coli-derived (recombinant DNA technique), as well as alpha-, alpha-2, arg, and beta-interferons, it was found that: Unlike HRF, the interferons neither induced histamine release nor affected antigen-induced histamine release from human basophils in vitro. HRF is partially acid-stable whereas gamma-interferon is acid labile. HRF samples had little interferon activity which did not correlate with HRF activity. The estimated molecular weight of HRF is 12,000-18,000 daltons and contrasts to those of interferons, which exceed 30,000 daltons. The results strongly suggest that HRF is very unlikely to be a gamma-interferon or indeed any other class of interferon.

The in vitro production of the histamine-releasing lymphokine (histamine-releasing factor, HRF) was studied. HRF was found to be producible from the mononuclear cells of most individuals following stimulation with the T-cell mitogen-concanavalin-A (Con-A). Kinetic studies showed that HRF production was an early event in cellular response to activation--beginning as early as 6 h after activation thus preceding lymphoproliferation which was not apparent until about 24 h after activation. Only a 3 h pulse-stimulation of the cells was found to be necessary for HRF production to occur. Furthermore, the presence of foetal calf serum supplement in the culture medium was found to be unimportant for production. Inhibitors of DNA, RNA and protein synthesis--mitomycin C, actinomycin D and puromycin respectively, in a dose range of 10-25 micrograms/ml, completely abolished HRF production. The results are discussed with regards to the nature of HRF as a genuine product of lymphocyte activation.

OBJECTIVE

To evaluate the effects of portaazygous disconnection (PAD), portacaval shunt (PCS) and distal splenocaval shunt (DSCS) on the portosytemic shunting (PSS), hepatic function (HF), hepatic mitochondrial respiratory function (HMRF), oral glucose tolerance test (OGTT) and arterial ketone body ratio (KBR) in order to provide a sound basis for selecting suitable operations for patients.

METHODS

Using a cirrhotic portal hypertensive model induced by CCl4/ethanol in Wistar rats, the PSS, HF, HMRF, OGTT and KBR were determined three weeks after PCS, DSCS and PAD.

RESULTS

It was revealed that: (1) In the cirrhotic portal hypertension rats, the PSS increased significantly, HMRF and hepatic reserve function (HRF) decreased significantly when compared with the control rats. (2) At the time of first postoperative week, the mean blood glucose value in the 120-minute OGTT in each PAD, PCS and DSCS groups had significant differences compared with the cirrhotic control group. But during the second and third postoperative weeks, the mean blood glucose values in the 120-minute OGTT in both PAD and DSCS groups had no significant differences compared with the cirrhotic control group except for the PCS group. The values of KBR in the three operative groups decreased significantly compared with the cirrhotic control group during the two postoperative weeks. In the third postoperative week, only the values of KBR in the PCS group had a significant difference compared with the cirrhotic control group. (3) After PCS, the PSS was further increased; HF and HMRF were significantly decreased. Little improvement was found in the third postoperative week. (4) After DSCS and PAD, the above mentioned indices were less influenced, and they were restored more quickly than those in the PCS group.

CONCLUSIONS

We found that PAD and DSCS are more desirable than PCS.

While diagnoses of hypoxemic respiratory failure (HRF) and pulmonary hypertension (PH) in preterm infants may be based on criteria similar to those in term infants, management approaches often differ. In preterm infants, HRF can be classified as 'early' or 'late' based on an arbitrary threshold of 28 postnatal days. Among preterm infants with late HRF, the pulmonary vascular abnormalities associated with bronchopulmonary dysplasia (BPD) represent a therapeutic challenge for clinicians. Surfactant, inhaled nitric oxide (iNO), sildenafil, prostacyclin and endothelin receptor blockers have been used to manage infants with both early and late HRF. However, evidence is lacking for most therapies currently in use. Chronic oral sildenafil therapy for BPD-associated PH has demonstrated some preliminary efficacy. A favorable response to iNO has been documented in some preterm infants with early PH following premature prolonged rupture of membranes and oligohydramnios. Management is complicated by a lack of clear demarcation between interventions designed to manage respiratory distress syndrome, prevent BPD and treat HRF. Heterogeneity in clinical phenotype, pathobiology and genomic underpinnings of BPD pose challenges for evidence-based management recommendations. Greater insight into the spectrum of disease phenotypes represented by BPD can optimize existing therapies and promote development of new treatments. In addition, better understanding of an individual's phenotype, genotype and biomarkers may suggest targeted personalized interventions. Initiatives such as the Prematurity and Respiratory Outcomes Program provide a framework to address these challenges using genetic, environmental, physiological and clinical data as well as large repositories of patient samples.

We have characterized the histamine-releasing factors (HRF) from a B-lymphoblastoid cell line (RPMI 8866), compared it to mononuclear cell-derived HRF, and distinguished these from the IgE-binding factor produced by RPMI 8866. The B-cell-derived HRF fractionates at molecular weights of 90,000, 70,000, and 12-15,000 while mononuclear cell HRF has a major component at 24-26,000. The isoelectric points for B-cell HRF are 6.2-6.3 and 6.6-6.8 in contrast to 6.9 and 7.3 for mononuclear cell-derived HRF. The kinetics of histamine release by either HRF was the same, with half-maximal release in 5-10 min, unlike the rapid release caused by anti-IgE. Since HRF has been reported to be an IgE-binding factor, we screened column fractions for the IgE-binding factor secreted by RPMI 8866; this is known to be a shed low affinity IgE receptor. The chromatographic pattern and isoelectric point of this IgE-binding factor does not correspond to HRF; the purified IgE-binding factor had no significant histamine releasing activity on human basophils, and neither source of HRF was reactive in a radioimmunoassay to the IgE-binding factor. Our data suggest that HRF is quite heterogeneous and varies in physiochemical properties depending upon the cell source. The molecular relatedness (or nonrelatedness) of those HRFs is unclear; however, our data indicate that although HRF or fractions therefrom may bind to IgE as has been reported, it is unrelated to the low affinity IgE receptor.

The production of histamine-releasing factor (HRF) by human mononuclear cells has previously been reported. In this paper we describe the production of HRF by guinea pig spleen cells, thymocytes, and PBMC. Guinea pig lymphoid cells were cultured either alone or in the presence of mitogens (PHA and Con A) or specific Ag(OVA and keyhole limpet hemocyanin) and the dialyzed cell-free supernatant was tested for histamine-releasing activity on guinea pig lung mast cells and blood basophils. Lung mast cells were isolated by enzymatic digestion and partially purified by countercurrent elutriation and discontinuous Percoll gradient centrifugation. Guinea pig spleen cells, thymocytes, and PBMC spontaneously produced significant amounts of HRF. The production was enhanced upon stimulation with PHA or specific Ag in animals immunized with Ag in CFA. Two distinct species of HRF were identified with m.w. of 50,000 to 70,000 and 5000 to 8000 by gel chromatography. HRF is a trypsin- and chymotrypsin-sensitive heat-stable protein. It does not bind to Con A-Sepharose and its production is not inhibited by tunicamycin. HRF-induced histamine release from lung mast cells is a temperature-dependent process and is complete in 10 min at 37 degrees C. Intradermal injection of HRF caused an immediate ear-swelling reaction in guinea pigs. The most severe ear-swelling reactions did not resolve within 1 h, but instead evolved over a period of 12 to 24 h.

Histamine releasing factor (HRF) generated in vitro by spleen cells of immunized mice activates homologous peritoneal mast cells (both normal and sensitized) for small but consistent, dose-dependent histamine and 5-hydroxytryptamine release. Both the time-course of this release and its susceptibility to the enhancing effect of D2O were similar to those observed in IgE-induced release; however, simultaneous challenge of sensitized mast cells with HRF and specific antigen or anti-IgE showed an additive effect, suggesting that mediator release by HRF and by the IgE system are independent of one another.

Mouse spleen cells have been shown to produce a histamine releasing factor (HRF) after stimulation with mitogen or specific antigen in vitro. The supernatants from the cultures of mouse spleen cells released not only histamine but also 5-hydroxytryptamine (5-HT) from homologous mast cells in a dose-dependent manner. The time-course of this release was similar to that observed in antigen or anti-IgE reaction. Heavy water (D2O) enhanced supernatant-induced mediator release.

OBJECTIVE

To assess the comprehensive effects of raloxifene hydrochloride on retinal, choroidal and retrobulbar hemodynamics and on visual function in post-menopausal women.

METHODS

Twenty-four post-menopausal women (age 55 +/- 3.8 years) were recruited for this cross-sectional study: 12 received placebo and 12 received raloxifene hydrochloride 60 mg once a day for 3 months. Baseline measurements of both groups included heart rate (HR), blood pressure (BP), visual acuity, contrast sensitivity and intraocular pressure (IOP) for both eyes. A comprehensive ocular blood flow (OBF) assessment was obtained for each patient in a randomly chosen study eye. Retinal blood flow data was obtained using confocal scanning laser Doppler flowmetry [Heidelberg Retinal Flowmeter (HRF)]. Color Doppler imaging (CDI) was used to assess retrobulbar hemodynamics in the ophthalmic, central retinal, short nasal and temporal posterior ciliary arteries. Baseline vision and hemodynamics in post-menopausal subjects were compared using paired Student's t tests, and the percentage change in baseline versus 3-month parameters was analyzed.

RESULTS

There were no statistically significant differences between 3 months of raloxifene therapy and placebo in terms of age, HR, arterial or mean BP, visual acuity, contrast sensitivity, IOP or retinal or retrobulbar blood flow.

CONCLUSIONS

Raloxifene therapy at 60 mg/day had no clinically significant impact on BP, IOP or OBF in post-menopausal women.

OBJECTIVE

To study retinal blood flow and vessel diameter after intra-ocular pressure (IOP) reduction in high- and low-pressure glaucomas, that is, exfoliation glaucoma (ExG) and normal-tension glaucoma (NTG).

METHODS

The study included 17 eyes with ExG and 20 with NTG. A minimum of 25% IOP reduction was achieved by deep sclerectomy. Blood flow in the temporal peripapillary retina was measured with scanning laser Doppler flowmetry (Heidelberg Retina Flowmeter, HRF), and retinal vessel diameters were evaluated with the retinal vessel analyser (RVA). Examinations were carried out before and 3 months after the operation.

RESULTS

Pre-operative IOP was significantly higher in ExG than in NTG (median 26 mmHg, range 20-33 mmHg versus 15 mmHg, 12-20; p < 0.001). Surgery reduced IOP significantly both in ExG eyes (postoperative IOP 13 mmHg, 5-17; p < 0.001) and NTG eyes (9 mmHg, 3-13; p < 0.001). After the operation, systolic retinal flow was significantly reduced in ExG eyes, whereas in NTG, HRF parameters remained unchanged. Pre-operatively, the central retinal artery equivalent (CRAE) and arteriovenous ratio (AVR) were higher in ExG than in NTG eyes. After IOP reduction, both CRAE and AVR were reduced in ExG eyes, but remained unchanged in NTG.

CONCLUSIONS

The study showed that before IOP reduction, arterial diameter was larger in ExG eyes than in NTG eyes. IOP reduction resulted in vasoconstriction and reduction of flow in ExG, whereas in NTG, both vessel diameter and retinal flow remained unchanged.

OBJECTIVE

We investigated the angiogenesis and density of newly formed blood vessels in embryonal tumors in relation to Ki-67, bcl-2, p-53 and p-27 expression.

METHODS

Forty-five children with embryonal tumors were enrolled in the study. Forty patients had a medulloblastoma (MB) and 5 patients had atypical teratoid/rhabdoid tumor (AT/RT).

RESULTS

In MB, the 5-year PFS and OS was 62.5 and 70%, respectively. Patients with Ki-67 index >50%, bcl-2 index >30% and higher density of new vessels were associated with worse survival. In the multivariate analysis, Ki-67 index was identified as a factor with independent prognostic power. In AT/RTs, high density of new vessels (>25 HRF) was observed in 3 patients and Ki-67 index over 25% was found in 4 patients.

CONCLUSIONS

Increased Ki-67, bcl-2 and density of new vessels are of prognostic value for the disease outcome in MB.

OBJECTIVE

The purpose of this study was to develop a radiobiological model of reoxygenation that fulfills the following goals: (a) Quantify the reoxygenation effect for different fractionations (b) Model the hypoxic fraction in tumors as a function of the number of radiation treatments. (c) Develop a simple analytical expression for a reoxygenation term in biological effect calculations.

METHODS

The model considers tumor cells in two compartments: an aerobic (or normoxic) population of cells and a hypoxic population including cells under a range of reduced oxygen concentrations. The surviving fraction is predicted using the linear-quadratic (LQ) model. A hypoxia reduction factor (HRF) is used to quantify reductions in radiosensitivity parameters αA and βA as cellular oxygen concentration decreases. The HRF is defined as the ratio of the dose at a specific level of hypoxia to the dose under fully aerobic conditions to achieve equal cell killing. The model assumes that a fraction of the hypoxic cells (Δ) moves from the hypoxic to the aerobic compartment after each daily fraction. As an example, we compare the effect of reoxygenation on biological response for a standard dose fractionation for nonsmall cell lung cancer (NSCLC) (d = 2 Gy, n = 33) to typical fractionations for stereotactic body radiotherapy (SBRT) and other nonstandard fractionations.

RESULTS

The reoxygenation effect is parameterized for biological effect calculations and an analytic expression for the surviving fraction after n daily treatments is derived. The hypoxic fraction either increases or decreases with n depending on the reoxygenation parameter Δ. For certain combinations of parameters, the biological effect of reoxygenation goes as -(n-1) · ln(1-Δ) providing a simple expression that can be introduced in biologically effective dose (BED) calculations. The model is used to compare fractionation schedules and quantitatively interpret results from molecular imaging studies of hypoxia. Based on the comparison of conventional fractionation and hypo- and hyper-fractionation for NSCLC, the value of Δ is estimated to be between 0.1 and 0.2 assuming plausible radiobiological parameters from the literature. This value is consistent with the preliminary analysis of the molecular imaging studies.

CONCLUSIONS

A novel radiobiological model was developed that can be used to evaluate the effect of reoxygenation in fractionated radiotherapy.

We set up in vitro several human colorectal neoplastic cell lines that we labelled "hormone-sensitive" (HS) in comparison to the original cell lines which appeared to be rather "hormone-insensitive" (HI). We used LoVo and HCT-15 human colorectal neoplastic cell lines and studied the influence of 17 beta-oestradiol (E2), gastrin and two gonadotropin-releasing hormone (GnRH) analogues, HRF and buserelin, on the proliferation of the HS and HI variants of the LoVo and HCT-15 cell lines. Cell proliferation was evaluated by a colorimetric assay, the MTT test. Our results show that E2, gastrin, HRF and buserelin did not induce a significant stimulatory influence on the HI variants of the LoVo and HCT-15 cells, i.e. the cells that were cultured in a hormone-free 10% FCS-supplemented medium. In sharp contrast, the colorectal cells cultured for 30 passages in an E2 and/or gastrin + 1% FCS-supplemented medium showed a marked tropic response to E2, gastrin, HRF and buserelin. However, the HS variants of the HCT-15 cells appeared less sensitive to the two GnRH analogues than did the HS variants of the LoVo cells.

The aim of this study was to improve our ability to interpret and validate Heidelberg Retina Flowmeter (HRF) flow images by recording flow measurements from specific regions of the retinal vasculature by taking advantage of the ability to precisely regulate perfusion flow in an isolated eye preparation. The retinal vasculature in 16 isolated perfused pig eyes was perfused with a 50%/50% Krebs/RBC solution at known flow rates ranging from 0 to 300 microl min(-1). At each flow rate, HRF images were obtained at a location approximately two disc diameters from the disc. After HRF image acquisition, the retinal vasculature was perfused with fluorescein isothiocyanate for fluorescence microscopy. Using the standard HRF software and a 10 x 10pixel measurement window, flow rates were measured from a retinal artery, vein, arteriole, venule, and the retinal capillary bed and a capillary-free-zone. The relationship between HRF measured flow and perfusion flow in the different measurement locations was determined. At zero perfusion flow the measured HRF flow was consistently greater than zero ( approximately 170 arbitrary units (AU)), and not significantly different at each measurement location except for the retinal vein, which had a significantly higher HRF flow value ( approximately 230AU). At higher perfusion flow rates the flow signal from the larger vascular elements (arteries and veins) increased rapidly thereafter to reach several thousand AU at a total perfusate flow of 50 microlmin(-1) and increased less rapidly at higher flow rates. In arterioles, the HRF flow was more linear over a broader range of perfusate flow rates but the peak flow signal was an order of magnitude smaller than that from the retinal artery. Both the linearity and magnitude of the flow signal in venules was less than that in arterioles. In capillary areas and in the capillary free zone, the HRF flow showed only a very weak relationship to perfusion flow when compared to the background noise. The choice of location for HRF flow analysis greatly influences the ability of the technique to measure changes in retinal blood flow. The major arteries and veins provide the strongest signal and greatest signal to noise ratio. However, the retinal arterioles produce an HRF signal that is more linear over a wider range of perfusate flow rates.

OBJECTIVE

Inhaled nitric oxide (iNO) is used to treat neonates with hypoxic respiratory failure (HRF). The aim of this study was to determine clinical characteristics and factors associated with non-response to iNO therapy that may assist in clinical management and weaning strategies.

METHODS

Retrospective chart review. The study cohort included gestational age ≥34 weeks' infants with acute HRF who received iNO within 7 days of birth. Subjects were stratified as responders or non-responders to iNO. Non-responders were defined as infants with failure to improve their PaO2 >20 mm Hg within 6 h of iNO initiation, need for extracorporeal membrane oxygenation (ECMO), or mortality. Clinical and laboratory characteristics were then compared between groups.

RESULTS

Forty four subjects were included. There were 31 responders and 13 non-responders to iNO therapy. Regression analysis showed significant correlation between a non-response to iNO therapy and changes in PaO2 and pH levels. We found for every 10 mm Hg decrease in PaO2 immediate post-iNO therapy there is a 17.5% decrease in the likelihood of responding to iNO (odds ratio [OR] 0.98, P=0.012). Similarly, for every 0.15 point decrease in pH, there is a 16.3% increased chance of not responding to iNO therapy (OR 1.16, P=0.002). The need for pressor support prior to iNO initiation was also found to be associated with a non-response (OR 2. 94, P=0.034).

CONCLUSIONS

Hypotension requiring treatment with pressors at the time of iNO therapy, as well as changes in pH and PaO2 after iNO initiation can be used as early clinical predictors to identify patients quickly who may be iNO non-responders.

OBJECTIVE

This study compared differences in balance measures among elderly adults with different degrees of balance impairments under different visual conditions.

METHODS

This study was conducted on 89 adults >> 60 years) with balance impairments. Subjects were divided into 3 groups based on the initial Tinetti score: low risk of fall (LRF, n=29), moderate risk of fall (MRF, n=30) and high risk of fall (HRF, n=30). Three balance measures-Tinetti, Timed-up and Go (TUG), and Functional Reach-were tested with 2 different visual conditions: eyes open with normal vision (EONV) and eyes open with blurred vision (EOBV). All data were analyzed using repeated measures analysis of variance.

RESULTS

Subjects with EOBV had significantly decreased Tinetti (P < .01 ) and Functional Reach (P < .01 ) scores and increased TUG (P < .01 ) scores regardless of fall group. Subjects in the LRF group performed better in all 3 tests than those in MRF (P < .01 ) and HRF (P < .01 ) groups. Subjects in the MRF group performed better in all 3 tests than those in HRF (P < .01 ). There were significant interactions between vision and risk of falls in Tinetti (P < .01 ) and TUG (P < .01 ) scores. However, there was no significant interaction between vision and risk of falls in Functional Reach (P>> .05) scores.

CONCLUSIONS

Blurred vision significantly altered all 3 balance measure scores in all risk groups. However, blurred vision had a greater influence on Tinetti and TUG scores than Functional Reach scores in subjects with higher risk of falls.

A high-performance thin-layer chromatography (HPTLC) method was developed for quantification of α-amylase inhibitory activity and stigmasterol content in ant plant extracts. An improved HPTLC method for the determination of total free radical scavenging activity in samples using DPPH• is also reported. For quantification of α-amylase inhibitory activity, the developed HPTLC plate is dipped into an α-amylase solution, and the bioautogram is then incubated at 25 °C for 30 min under humid conditions. For visualization of enzyme inhibitory activity, the starch test with an iodine indicator solution is used. The blue zone observed comes from the starch-iodine complex formed from starch that was not hydrolyzed by the amylase due to enzyme inhibition by the compound(s) present in the sample. The area of the blue zones was used to compare and quantify relative α-amylase inhibitory activity in different extracts. Location of the blue zones (hRF) on the plate was used to detect compounds that are responsible for the α-amylase inhibitory activity. Relative α-amylase activity was not related to the antioxidant activity, but was highly correlated with the stigmasterol content in the sample extracts (R = 0.95). Therefore, plant sterols present in the extracts might be responsible for α-amylase inhibitory activities in the extracts. •The developed method for quantification of α-amylase inhibitory activity provides an efficient and effective tool that can be used to screen, detect and quantify α-amylase inhibitory activity in plant extracts.•The proposed protocol is easy to run, involves minimal sample preparation, with multiple samples able to be analyzed in parallel on the same chromatographic plate, in a short time.•There were significant differences in α-amylase inhibitory activity, stigmasterol content, and total free radical scavenging activity between methanol, ethanol, dichloromethane, and ethyl acetate ant plant extracts.