A Smart Phone Based Handheld Wireless Spirometer with Functions and Precision Comparable to Laboratory Spirometers.

We report a smart phone based handheld wireless spirometer which uses a Lilly type sensing flowhead for respiratory signal acquisition and transmits the data to smartphone or other mobile terminals with Bluetooth signal transmission for data processing and result display. The developed spirometer was demonstrated to be able to detect flow rates ranging from 0-15 L/s with an accuracy of 4 mL/s, and can perform tests of flow volume (FV), forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow (PEF), etc. By having the functions and precision comparable to laboratory spirometers, it satisfies the American Thoracic Society and European Respiratory Society (ATS/ERS) proposed performance requirements for spirometer. At the same time, it is low cost, light and handy, low power consumption battery-powered. The test of 12 cases of subjects using the developed spirometer also indicated that it was easy to use for both providers and patients, and suitable for the Point of Care Test (POCT) of chronic obstructive pulmonary disease (COPD) and asthma at general-practice settings and homes.

Restoring the youth of aged red blood cells and extending their lifespan in circulation by remodelling membrane sialic acid.

Membrane sialic acid (SA) plays an important role in the survival of red blood cells (RBCs), the age-related reduction in SA content negatively impacts both the structure and function of these cells. We have therefore suggested that remodelling the SA in the membrane of aged cells would help recover cellular functions characteristic of young RBCs. We developed an effective method for the re-sialylation of aged RBCs by which the cells were incubated with SA in the presence of cytidine triphosphate (CTP) and α-2,3-sialytransferase. We found that RBCs could be re-sialylated if they had available SA-binding groups and after the re-sialylation, aged RBCs could restore their membrane SA to the level in young RBCs. Once the membrane SA was restored, the aged RBCs showed recovery of their biophysical and biochemical properties to similar levels as in young RBCs. Their life span in circulation was also extended to twofold. Our findings indicate that remodelling membrane SA not only helps restore the youth of aged RBCs, but also helps recover injured RBCs.

[Surface-enhanced Raman spectra analysis of trace degradation products from goat horn].

Nano-silver colloid was synthesized by using microwave method on the mixtures of sodium citrate solution and silver nitrate solution. The method has advantages of fast heating speed, uniform temperature distribution and easily controlled reaction conditions. The sizes and size distributions of the silver particles were characterized by means of quasi-elastic laser scattering (QLS). The average particles size was (53.27 +/- 2.65) nm and the size of the particles was mainly distributed around 56 nm. Surface-enhanced Raman spectra of the degradation products from goat horn were obtained with silver colloid as active substrate. It was observed that the Raman signal of SERS was enhanced significantly compared with that of regular Raman spectrum, especially at the Raman bands of 659, 830, 850, 929, 999, 1 028, 1 280, 1 439 and 1 599 cm(-1) which reflect the biochemical components in degradation products. The characteristic Raman bands of degradation products from goat horn were preliminary assigned. The assignments showed that the main constituents of the degradation products from goat horn were amino acids and polypeptides. It was for the first time that Surface-enhanced Raman spectroscopy was used to detect trace degradation products from the horns. Raman signal enhancement can be obtained with high sensitivity for the trace concentrations as low as ppm level. It is concluded that surface-enhanced Raman spectroscopy can provide a fast, direct and precise detecting method for the detection of trace degradation solution from horns.

Nano-optical method for transforming a single yeast cell using exogenous genes.

We report a highly efficient nano-optical method for transforming a single yeast cell using exogenous genes. It used laser tweezers or micromanipulators to immobilize the cell immersed in a DNA solution and created a transient nano-sized hole on its cell wall concurrently with laser scissors to deliver nano moles of DNA into the cell. With this method, one can directly transfer the naked DNA of exogenous genes into yeast cells for transformation. We successfully transformed S. cerevisiae yeasts respectively with GFP (Green Fluorescent Protein) plasmid and the nucleic acid extraction of a bacteria GF1 from the gut of Coptotermes formosanus termites. The experimental results demonstrated that the recombinants had high survival rate and transformation efficiency (28%). The recombinant GFP-yeast system showed green fluorescence for generations. GF1 DNA sequences were incorporated into the yeast genome as a heritable component with stable expression for multi-generations so that the recombinant GF1-yeast had a strong capability of digesting biomass as GF1. Our method would apply to different cells with cell walls for various gene transformations.

AI Aided Analysis on Saliva Crystallization of Pregnant Women for Accurate Estimation of Delivery Date and Fetal Status.

Saliva contains similar molecular components to serum. Analysis of saliva can provide important diagnostic information about the body. Here we report an artificial intelligence (AI) aided home-based method that can let pregnant women perform daily monitoring on their pregnant status and accurate prediction on their delivery date by the pattern analysis of their salivary crystals. The method was developed based on the information obtained from our investigation on the saliva samples of 170 pregnant women about the correlation of the salivary crystal pattern with pregnant age and fetal status. It demonstrated that the patterns of salivary crystallization could act as indicators of the pregnant age, fetal state, and some medical conditions of pregnant women. On this basis, with the aid of AI recognition and analysis of the fractal dimension and some characteristic crystals in the salivary crystallization, we performed estimation on the delivery date in both quantitative and qualitative manners. The accuracy of the prediction on 15 pregnant women was satisfactory: 100% delivering in the predicted week, 93.3% within the estimated three days, and 86.7% on the day as the prediction. We also developed a simple smartphone-based AI-aided salivary crystal imaging and analysis device as an auxiliary means to let pregnant women monitor their fetal status daily at home and predict their delivery date with adequate accuracy.

Human red blood cell aging: correlative changes in surface charge and cell properties.

Red blood cells (RBCs) during microcirculation, aging and storage, lose N-acetylneuraminic acid (NANA) and other biomaterials thereby altering cell structures, some properties and functions. Such cell damage very likely underlies the serious adverse effects of blood transfusion. However, a controversy has remained since 1961-1977 as to whether with aging, the RBCs, suffering loss of NANA, do have a decreased charge density. Any correlation between the changes in the cell properties with cell aging is also not clear. Therefore, to remove the ambiguity and uncertainty, we carried out multiparameteric studies on Percoll fractions of blood of 38 volunteers (lightest-young-Y-RBCs, densest-old-O-RBCs, two middle fractions).We found that there were striking differences between the properties of Y-RBCs and O-RBCs. The ζ-potential of Y-RBCs decreased gradually with aging. Studies in parallel on RBC fractions incubated with both positively charged quantum dots and Sambucus Nigra-fluorescein isothiocyanate (FITC) along with their ζ-potentials provide for the first time direct visual evidence about the lesser amount of charge density and NANA on O-RBCs, and a collinear decrease in their respective ζ-potentials. Close correlation was found between the surface charge on an aging RBC and its structure and functions, from the cell morphology, the membrane deformability to the intracellular Hb structure and oxidation ability. This quantitative approach not only clarifies the picture but also has implications in biology and medicine.

[Study of spectrum processing method for Raman microscopy on single living cell].

To study the spectrum processing methods for Raman microscopy on single living cell and develop the pre-process techniques for Raman spectrum of single living cell to enhance the signal to noise ratio, sensitivity, and decrease the fluorescence influence, wiping off the cosmic rays was used to improve the spectrum. The spectra classification, spectra average and filtration were applied to enhance signal to noise ratio. The fluorescence was depressed for quantity analysis or utilized for analysis by comparing the background and the spectra. Results show that (1) comparing the spectra with short exposure time and more scans can wipe off the cosmic rays effectively. (2) the spectra classification, spectra average and filtration can improve the quality of spectra and can show some weak and sensitive bands. (3) sometimes the fluorescence has useful information. It is concluded that the proposed techniques for Raman spectrum of single cell in this paper can show the sensitive and weak intensity peaks and reflect the information of molecules structures very well.

[Qualitative analysis of Raman spectra based on pulse coupled neural network].

By studying on pulse coupled neural network (PCNN) and Raman spectra qualitative analysis, a method based on PCNN for Raman spectra qualitative analysis was proposed. After encoding the Raman spectra by using PCNN neurons' characteristics of fatigue and refractory period, the improved Horspool algorithm was used to match the code corresponding to the detected sample with all of the base code in the database one by one, and then their matching similarity was acquired to determine the sample type. Experimental results and analysis of data proved that the method proposed in this paper is accurate and effective for Raman spectra qualitative analysis. Meanwhile, traditional qualitative analysis method based on spectral template has some deficiencies, like that it is difficult to determine the characteristic peak of the detected sample and the matching analysis process has a high degree of redundancy. While our proposed method not only can avoid these deficiencies very well, but also needs a small amount of data storage. The requirement of the storage space was only 5.8% of that used in the traditional qualitative analysis method based on spectral template.

[Normalization methods for ethanol Raman spectra quantitative analysis].

By performing different Raman normalization methods for ethanol quantitative analysis, the authors proposed the method which used the highest band intensity of the ethanol Raman spectra in the maximum concentration as the normalization metric for ethanol concentration quantitative analysis. By using this method, the correlation coefficient was 0.999, the mean relative error was only 0.067 8, and the relative standard deviation (RSD) of the data from different experimental groups was 0.046 3. Both the validity and accuracy of this method were much better than the internal standard and ratio methods. Combined with baseline correction, the method can not only effectively resist the data fluctuation between different experimental groups, but also improve the accuracy of ethanol quantitative analysis obviously. The test using the method to measure the ethanol concentration of some wines from market proved that the relative standard deviations were all smaller than 0.012, indicating that the method is excellent for ethanol concentration quantitative analysis in commercial applications.

[Raman spectra quantitative analysis on materials with strong fluorescence background].

Aiming at the difficulty of Raman spectra quantitative analysis on materials with strong fluorescence background, together with baseline correction, a new normalization method was performed for concentration quantitative analysis of two kinds of solutions which exhibit strong fluorescence background, the methanol solutions with different concentrations and the mixed solutions of ethanol and methanol with different ratios of concentration. Meanwhile, the data fluctuation caused by collecting spectra data at different space-time was investigated by using statistical method of randomized blocks analysis of variance to evaluate the data fluctuation among different sample groups, and the function of our method proposed in this paper to eliminate this data fluctuation was discussed. Experimental results demonstrate that our proposed method can not only obtain satisfied accuracy for Raman spectra quantitative analysis on methanol with strong fluorescence background, with the mean relative error being 4.7%, but also effectively eliminate the data fluctuation among different sample groups, and the relative standard deviation of them was only 4.2%, indicating that it is possible to carry out simple, quick and precise quantitative determination of sample content for the materials with strong fluorescence background.

Effects of Low-Dose X-Ray on Cell Growth, Membrane Permeability, DNA Damage and Gene Transfer Efficiency.

BACKGROUND: We aimed to reveal if low dose X-rays would induce harmful or beneficial effect or dual response on biological cells and whether there are conditions the radiation can enhance gene transfer efficiency and promote cell growth but without damage to the cells. METHOD: A systematic study was performed on the effects of Kilo-V and Mega-V X-rays on the cell morphology, viability, membrane permeability, DNA damage, and gene transfection of 293 T and CHO cells. RESULTS: The Kilo-V X-rays of very low doses from 0.01 to 0.04 Gray in principle didn't induce any significant change in cell morphology, growth, membrane permeability, and cause DNA damage. The Mega-V X-ray had a damage threshold between 1.0 and 1.5 Gray. The 0.25 Gray Mega-V-X-ray could promote cell growth and gene transfer, while the 1.5 Gray Mega-V X-ray damaged cells. CONCLUSION: The very low dose of KV X-rays is safe to cells, while the effects of Mega-V-X-rays are dose-dependent. Mega-V-X-rays with a dose higher than the damage threshold would be harmful, that between 1.0 -1.5 Gray can evoke dual effects, whereas 0.25 Gray MV X-ray is beneficial for both cell growth and gene transfer, thus would be suitable for radiation-enhanced gene transfection.

[Technique of confocal Raman microscopy on erythrocytes].

The technique of confocal Raman scanning microscopy (point scanning, line scanning and 2D scanning) and bright field imaging of living erythrocytes was investigated as a function of different scanning conditions at the excitation wavelength of 514 nm. The biological effect of the 514 nm laser radiation on the erythrocytes was also evaluated, so that a set of proper scanning parameters for different scan modes can be determined to obtain strong enough Raman signal while without damage on the living cells by evaluating the change of Raman spectra and lighted field images of the cells. For the point scanning mode, the laser power at sample is the most important parameter to be adjusted, which normally should be less than 1.5 mW. For the line scanning mode, the laser power at sample and scanning step should be considered at first. Small scanning step means the energy of laser accumulated at a small region, which can easily damage to erythrocytes. Large scanning step can reduce the damage; however the spatial resolution decreases also. It is recommended that scanning step should be more than 0.5 microm and laser power at sample should be less than 0.7 mW. For the 2D scanning mode, besides the laser power at sample, scan step needs to be adjusted, and other scan parameters need to be adjusted properly for reducing the effect of laser on erythrocytes. Large pinhole and relative low temperature of sample are the remedies, which can reduce the effect of laser on erythrocytes. 1.0 microm scanning step, 0.7 mW laser power at sample, 500 microm pinhole and proper low temperature can get better 2D Raman image of erythrocytes. For all scanning modes, if the Raman signal is strong enough, the exposure time can be shortened properly, thus reducing the effect of laser on erythrocytes. The optimization of experiment process is also important for Raman test on living cells.

Technique of laser chromosome welding for chromosome repair and artificial chromosome creation.

Here we report a technique of laser chromosome welding that uses a violet pulse laser micro-beam for welding. The technique can integrate any size of a desired chromosome fragment into recipient chromosomes by combining with other techniques of laser chromosome manipulation such as chromosome cutting, moving, and stretching. We demonstrated that our method could perform chromosomal modifications with high precision, speed and ease of use in the absence of restriction enzymes, DNA ligases and DNA polymerases. Unlike the conventional methods such as de novo artificial chromosome synthesis, our method has no limitation on the size of the inserted chromosome fragment. The inserted DNA size can be precisely defined and the processed chromosome can retain its intrinsic structure and integrity. Therefore, our technique provides a high quality alternative approach to directed genetic recombination, and can be used for chromosomal repair, removal of defects and artificial chromosome creation. The technique may also have applicability on the manipulation and extension of large pieces of synthetic DNA.

Versatile on-stage microfluidic system for long term cell culture, micromanipulation and time lapse assays.

We report here a versatile on-stage microfluidic cell culture and assay system which is compatible with different microscopes and sensors, can simultaneously perform steps of long term cell culture, high throughput time lapse cell assays/imaging, and cell micromanipulations. With the system, we cultured a variety of cells for different periods of time and monitored their cell morphology, migration and division. We also performed a series non-invasive real time in situ time lapse assays and micromanipulations on different cells. They include: the first time lapse imaging and measurements on the instantaneous variations of morphology, biomechanical properties and the intracellular protein of human red blood cells in responding to pH fluctuation, drug action and electromagnetic radiation; the first continuous time lapse Raman micro-spectroscopy on a CHO cell in different phases of its entire life cycles; the micro-transfection of GFP into B16 cells and the follow up observation of the cell's morphology and expressed GFP fluorescence varying with incubation time and cell generations. The performance of these experiments not only demonstrated the capability of the system, but also proposed a variety of novel methods for obtaining time- and spatially-resolved information about the cellular and molecular heterogeneity and transformation during development or stimulations.

Simultaneous Determination of Glass Transition Temperatures of Several Polymers.

AIMS: A simple and easy optical method is proposed for the determination of glass transition temperature (Tg) of polymers. METHODS & RESULTS: Tg was determined using the technique of microsphere imaging to monitor the variation of the refractive index of polymer microsphere as a function of temperature. It was demonstrated that the method can eliminate most thermal lag and has sensitivity about six fold higher than the conventional method in Tg determination. So the determined Tg is more accurate and varies less with cooling/heating rate than that obtained by conventional methods. The most attractive character of the method is that it can simultaneously determine the Tg of several polymers in a single experiment, so it can greatly save experimental time and heating energy. CONCLUSION: The method is not only applicable for polymer microspheres, but also for the materials with arbitrary shapes. Therefore, it is expected to be broadly applied to different fundamental researches and practical applications of polymers.

Easy and rapid multi-pass detection of antigen and antibody with micro-lens sensors.

We introduce a micro-lens imaging method that can perform easy and rapid multi-pass detection of antigen/antibody (Ag/Ab) without the requirement of any labeling, expensive enzymes, pre-immobilization/modification, and post-washing. Our method detects Ag or Ab presenting in solutions in a quantitative or qualitative manner by using micro-lens as the sensor to monitor the refractive index variation of the solutions during the primary stage of Ag-Ab reaction. The detection can be taken rapidly and finished in two minutes, while requires very low sample volume (several micron liters) and its detection limit can be as low as ∼pg/mL. The method is also able to provide kinetic and thermodynamic parameters of Ag-Ab reactions. The detections of ten Ag-Ab systems and two kinds of clinical samples demonstrated that our method is of high sensitivity, accuracy, reliability and permitting on-site analysis.

[Spectrum analysis of erythrocyte intracellular hemoglobin with a novel fast multi-channel micro-spectrophotometry].

With the application of a novel fast multi-channel micro-spectrophotometry (MMSP), the absorption spectrum of intracellular hemoglobin molecule in a human single living red blood cell was monitored under the altered physiological environments (pH, temperature, partial pressure of oxygen, and osmotic pressure). It was found that on the absorption spectrum curve of hemoglobin the spike, the height and the position of the characteristic absorption peaks at 540 and 575 nm were altered obviously with the changes in physiological conditions, indicating that the concentration, structure and function of the hemoglobin in the red blood cell may be closely associated with the physiological environments.

[Instant effect of temperature on the oxygen carrying capacity of single living intact red blood cell].

The instant effect of temperature on the absorption spectra of the hemoglobin in single living intact red blood cells was investigated, by employing a highly sensitive fast multi-channel micro-spectrophotometer system to perform non-invasive, in situ, real time measurements on the cells. It was found that both the heights and position of the specific peaks in the absorption spectra of intercellular hemoglobin were changed with temperature, indicating that the oxygen carrying capacity of red blood cells varies with temperature. The correlations of the structure and concentration as well as the function of hemoglobin, and the molecular mechanism were also discussed.

[The methods of shorting of proximal femoral and total hip arthroplasty for old femoral neck fracture with severe hip joint dislocation].

OBJECTIVE: To discuss the effective method and outcome to old femoral neck fracture with severe hip joint dislocation. METHODS: From April 1996, 7 cases of old femoral neck fracture with severe hip joint dislocation were treated by the shorting of posterior femoral and total hip arthroplasty. RESULTS: The average age of 7 patients was 51 years old and the mean follow-up was 27.3 months. The mean Harris score was improved to 84.3 from 36.7 before operation in the latest follow-up. The prosthesis position of acetabular and femoral was excellent, there was no sinking or softening of artificial joint, nonunion of femoral osteotomy. CONCLUSION: The preliminary clinical results are quite satisfactory of the shorting of posterior femoral and total hip arthroplasty to old femoral neck fracture with severe hip joint dislocation, the follow-up is necessary for further long-term outcome.

KrF excimer laser precision machining of hard and brittle ceramic biomaterials.

KrF excimer laser precision machining of porous hard-brittle ceramic biomaterials was studied to find a suitable way of machining the materials into various desired shapes and sizes without distorting their intrinsic structure and porosity. Calcium phosphate glass ceramics (CPGs) and hydroxyapatite (HA) were chosen for the study. It was found that KrF excimer laser can cut both CPGs and HA with high efficiency and precision. The ablation rates of CPGs and HA are respectively 0.081 µm/(pulse J cm(-2)) and 0.048 µm/(pulse J cm(-2)), while their threshold fluences are individually 0.72 and 1.5 J cm(-2). The cutting quality (smoothness of the cut surface) is a function of laser repetition rate and cutting speed. The higher the repetition rate and lower the cutting speed, the better the cutting quality. A comparison between the cross sections of CPGs and HA cut using the excimer laser and using a conventional diamond cutting blade indicates that those cut by the excimer laser could retain their intrinsic porosity and geometry without distortion. In contrast, those cut by conventional machining had distorted geometry and most of their surface porosities were lost. Therefore, when cutting hard-brittle ceramic biomaterials to prepare scaffold and implant or when sectioning them for porosity evaluation, it is better to choose KrF excimer laser machining.