[Analysis of influencing factors of pneumoconiosis complicated with pulmonary tuberculosis].

Objective: To investigate the influencing factors of pneumoconiosis complicated with tuberculosis in order to provide the scientific evidence for formulating the preventive strategies. Methods: From July 2019 to January 2020, all occupational pneumoconiosis patients reported in Guangzhou from 1958 to 2018 were investigated retrospectively (n=1155) . The basic data (including gender, diagnosis time, diagnosis age, dust exposure duration, period, pneumoconiosis disease type, work type and industry) were obtained from pneumoconiosis case card and network report database. The data of pulmonary tuberculosis were collected from the occupational disease diagnosis files of Guangzhou Occupational Disease Prevention and Control Hospital, and were supplemented by telephone follow-up. The distribution of pneumoconiosis and tuberculosis in Guangzhou was analyzed. Binary logistic regression analysis model was used to analyze the influencing factors of pneumoconiosis complicated with pulmonary tuberculosis. Results: Among the 1155 new cases of pneumoconiosis, 357 cases were pneumoconiosis tuberculosis, and the complication rate of tuberculosis was 30.9%. Year of diagnosis, age of diagnosis, dust exposure duration, pneumoconiosis caused by mineral dust and construction industry were influencing factors for pneumoconiosis complicated with pulmonary tuberculosis (OR=0.948, 1.048, 0.972, 3.112, 2.815, P<0.05) . After the adjustment of gender, diagnosis year, diagnosis age, dust exposure duration and diagnosis period, the risk of pulmonary tuberculosis in rock drilling workers was 1.462 times higher than that in other types of work (P<0.05) . Conclusion: The complication rate of tuberculosis in patients with pneumoconiosis is relatively high. The main influencing factors are the year of diagnosis, age of diagnosis, dust exposure duration, the type of pneumoconiosis and the industry. The importance of occupational health examination and health education on prevention and treatment of tuberculosis should be emphasized among dust-exposed workers and pneumoconiosis patients. People with susceptibility factors are the top priority.

[Application effect of sustainable skin-stretching device in scalp and soft tissue defect].

Objective: To explore the application effect of sustainable skin-stretching device in scalp and soft tissue defect. Methods: From June 2017 to January 2020, 5 patients (3 males and 2 females, aged 31-57 (38.0±2.1) years) with large area of scalp and soft tissue defect and skull exposure were admitted to Department of Reparative and Reconstructive Surgery of the Second Hospital of Dalian Medical University. The wound area ranged from 16.0 cm×8.0 cm to 18.0 cm×12.0 cm. The sustainable skin-stretching device was installed after debridement operation for scalp wound. The wound was stretched from the 3rd day after installation of the device, at a basic speed of 1 mm/d and finished for 3 times on average. During stretching, close attention was paid to the changes in blood flow of the wound margin and the subjective feeling of the patients. When the result was negative in the squeezing and pinching test for wound margin after stretching, the further stretching was stopped, the final stretching state was maintained for 3 days, and the wounds were sutured directly. The wound healing during stretching of sustainable skin-stretching device and the occurrence of complications were observed. The rest wound areas after stretching for 5, 10, 15, and 20 days were measured. The wound healing and hair growth were observed during follow-up. Results: All the wounds of 5 patients was sutured directly after stretching for 19-23 d. There was no tension blister on the margin of wounds during stretching, and the margin of wounds healed well after being sutured without skin necrosis. After stretching treatment for 5-20 d, the wound areas were gradually decreased. During follow-up of 2-11 (4.5±1.5) months, the elasticity, color, feeling, and regenerated hair growth of the stretched scalp tissue were close to those of the surrounding normal skin tissue. The linear scar formed on the margin of wounds, but no scar formed on the wounds. Conclusions: The application of sustainable skin-stretching device can reduce the difficulty in repairing scalp and soft tissue defect, with the regenerated hair growing well after treatment, which is worthy of clinical promotion.

Fabrication of 3D photonic components on bulk crystalline silicon.

We have fabricated three dimensional photonic components such as waveguides and beam splitters from crystalline silicon using a process based on one or more ion irradiation steps with different energies and fluences, followed by electrochemical anodization and thermal annealing. We first demonstrate the fabrication of multilevel silicon waveguides and then extend this process to make multilevel beam splitters, in which three output waveguides are distributed over two depths. The dimensions of the waveguides can be defined within a range from 0.5 µm to several micrometers simply by varying the ion beam fluence.

Binary logistic regression analysis of solid thyroid nodules imaged by high-frequency ultrasonography, acoustic radiation force impulse, and contrast-enhanced ultrasonography.

OBJECTIVE: The common clinical techniques used for examining thyroid tumors include palpation, imaging, immunoassays and tissue biopsy. Ultrasonography is easy, non-invasive, non-radioactive and highly reproducible imaging technique; however, due to the disease polytropism, diagnosis may become difficult sometimes. Ultrasound elastography, particularly acoustic radiation force impulse (ARFI) imaging and contrast-enhanced ultrasonography (CEUS) have been successfully used to diagnose the thyroid tumors. The objective of this retrospective study was to analyze and compare the solid thyroid nodules imaged by high-frequency ultrasonography (HFUS), ARFI imaging, and CEUS. PATIENTS AND METHODS: For this purpose, images of the 80 solid thyroid nodules (58 benign and 22 malignant) with surgical pathology were obtained and data were compared using binary logistic regression analysis. RESULTS: Morphology (p < 0.001), and internal calcification (p = 0.007) were statistically different. The mean shear wave velocity (SWV) measured by ARFI was significantly different (p = 0.029). Three sets of comparison on CEUS (p = 0.019) and time to peak (TTP) of CEUS were significantly different (p = 0.001). The logistic regression analysis indicated that the morphology, mean SWV of ARFI and TTP were independent risk factors for malignancy. The diagnostic accuracy for solid thyroid nodules was 85.1% (68/80) and the area under the receiver operating characteristic (ROC) curve was 0.945±0.033. CONCLUSIONS: Logistic regression analysis can effectively screen significant parameters for the differential diagnosis of solid thyroid nodules imaged by ultrasonography.

Reprogramming hMSCs morphology with silicon/porous silicon geometric micro-patterns.

Geometric micro-patterned surfaces of silicon combined with porous silicon (Si/PSi) have been manufactured to study the behaviour of human Mesenchymal Stem Cells (hMSCs). These micro-patterns consist of regular silicon hexagons surrounded by spaced columns of silicon equilateral triangles separated by PSi. The results show that, at an early culture stage, the hMSCs resemble quiescent cells on the central hexagons with centered nuclei and actin/ß-catenin and a microtubules network denoting cell adhesion. After 2 days, hMSCs adapted their morphology and cytoskeleton proteins from cell-cell dominant interactions at the center of the hexagonal surface. This was followed by an intermediate zone with some external actin fibres/ß-catenin interactions and an outer zone where the dominant interactions are cell-silicon. Cells move into silicon columns to divide, migrate and communicate. Furthermore, results show that Runx2 and vitamin D receptors, both specific transcription factors for skeleton-derived cells, are expressed in cells grown on micropatterned silicon under all observed circumstances. On the other hand, non-phenotypic alterations are under cell growth and migration on Si/PSi substrates. The former consideration strongly supports the use of micro-patterned silicon surfaces to address pending questions about the mechanisms of human bone biogenesis/pathogenesis and the study of bone scaffolds.

Sonoporation, drug delivery, and gene therapy.

Ultrasound is a very effective modality for drug delivery and gene therapy because energy that is non-invasively transmitted through the skin can be focused deeply into the human body in a specific location and employed to release drugs at that site. Ultrasound cavitation, enhanced by injected microbubbles, perturbs cell membrane structures to cause sonoporation and increases the permeability to bioactive materials. Cavitation events also increase the rate of drug transport in general by augmenting the slow diffusion process with convective transport processes. Drugs and genes can be incorporated into microbubbles, which in turn can target a specific disease site using ligands such as the antibody. Drugs can be released ultrasonically from microbubbles that are sufficiently robust to circulate in the blood and retain their cargo of drugs until they enter an insonated volume of tissue. Local drug delivery ensures sufficient drug concentration at the diseased region while limiting toxicity for healthy tissues. Ultrasound-mediated gene delivery has been applied to heart, blood vessel, lung, kidney, muscle, brain, and tumour with enhanced gene transfection efficiency, which depends on the ultrasonic parameters such as acoustic pressure, pulse length, duty cycle, repetition rate, and exposure duration, as well as microbubble properties such as size, gas species, shell material, interfacial tension, and surface rigidity. Microbubble-augmented sonothrombolysis can be enhanced further by using targeting microbubbles.

Use of ultrasound to enhance nonviral lung gene transfer in vivo.

We have assessed if high-frequency ultrasound (US) can enhance nonviral gene transfer to the mouse lung. Cationic lipid GL67/pDNA, polyethylenimine (PEI)/pDNA and naked plasmid DNA (pDNA) were delivered via intranasal instillation, mixed with Optison microbubbles, and the animals were then exposed to 1 MHz US. Addition of Optison alone significantly reduced the transfection efficiency of all three gene transfer agents. US exposure did not increase GL67/pDNA or PEI/pDNA gene transfer compared to Optison-treated animals. However, it increased naked pDNA transfection efficiency by approximately 15-fold compared to Optison-treated animals, suggesting that despite ultrasound being attenuated by air in the lung, sufficient energy penetrates the tissue to increase gene transfer. US-induced lung haemorrhage, assessed histologically, increased with prolonged US exposure. The left lung was more affected than the right and this was mirrored by a lesser increase in naked pDNA gene transfer, in the left lung. The positive effect of US was dependent on Optison, as in its absence US did not increase naked pDNA transfection efficiency. We have thus established proof of principle that US can increase nonviral gene transfer, in the air-filled murine lung.

Microbubble ultrasound improves the efficiency of gene transduction in skeletal muscle in vivo with reduced tissue damage.

Intramuscular injection of naked plasmid DNA is a safe approach to the systemic delivery of therapeutic gene products, but with limited efficiency. We have investigated the use of microbubble ultrasound to augment naked plasmid DNA delivery by direct injection into mouse skeletal muscle in vivo, in both young (4 weeks) and older (6 months) mice. We observed that the albumin-coated microbubble, Optison (licensed for echocardiography in patients), significantly improves the transfection efficiency even in the absence of ultrasound. The increase in transgene expression is age related as Optison improves transgene expression less efficiently in older mice than in younger mice. More importantly, Optison markedly reduces muscle damage associated with naked plasmid DNA and the presence of cationic polymer PEI 25000. Ultrasound at moderate power (3 W/cm2 1 MHz, 60 s exposure, duty cycle 20%), combined with Optison, increases transfection efficiency in older, but not in young, mice. The safe clinical use of microbubbles and therapeutic ultrasound and, particularly, the protective effect of the microbubbles against tissue damage provide a highly promising approach for gene delivery in muscle in vivo.

The role of ultrasound in molecular imaging.

Ultrasound has received less attention than other imaging modalities for molecular imaging, but has a number of potential advantages. It is cheap, widely available and portable. Using Doppler methods, flow information can be obtained easily and non-invasively. It is arguably the most physiological modality, able to image structure and function with less sedation than other modalities. This means that function is minimally disturbed, and multiple repeat studies or the effect of interventions can easily be assessed. High frame rates of over 200 frames a second are achievable on current commercial systems, allowing for convenient cardiac studies in small animals. It can be used to guide interventional or invasive studies, such as needle placement. Ultrasound is also unique in being both an imaging and therapeutic tool and its value in gene therapy has received much recent interest. Ultrasound biomicroscopy has been used for in utero imaging and can guide injection of virus and cells. Ultrahigh frequency ultrasound can be used to determine cell mechanical properties. The development of microbubble contrast agents has opened many new opportunities, including new functional imaging methods, the ability to image capillary flow and the possibility of molecular targeting using labelled microbubbles.

Continuous wave ultrasonic tomography.

As an object rotates with respect to a stationary ultrasonic beam, the scattering centers within the object return echoes that are Doppler-shifted in frequency by amounts depending on the velocities of the individual scatterers. The scattering centers that lie on a line of constant cross-range all have the same effective velocity in the direction pointing toward the transducer; therefore, the backscattered echo amplitude at any particular frequency is the line integral of the scattered radiation at the cross-range corresponding to that frequency. The amplitudes of the returned signals at other frequencies give the line integrals for the scatterers at the corresponding cross-ranges. The amplitude as a function of frequency can be interpreted as a tomographic projection. A continuum of the projections at different positions is generated while the object is rotating. A tomographic reconstruction algorithm can produce an image of the distribution of scattering centers in the insonified object from these projections. A microscanner was developed to investigate the approach of using continuous wave (CW) ultrasound for cross-sectional imaging. The resolution is limited by the target size and the ultrasonic wavelength.