[Analysis of early diagnosis and prevention techniques for occupational pneumoconiosis based on patent perspectives in China's coal industry]

Occupational pneumoconiosis in the coal industry is an occupational disease that seriously endangers coal miners' health. Early diagnosis and prevention techniques are significant in controlling its incidence rate and reducing its harm. This article takes the patent data related to the early diagnosis and prevention of occupational pneumoconiosis in the coal industry, published from 1985 to 2021, as the research object. It uses tools such as the Derwent Data Analyzer (DDA) software, the Patyee Database, and the PatSnap Database to analyze the technological development trend and characteristics in this field from aspects of growth trend, primary patent holders, IPC classification layout, value, and research and development hotspots. The results show that the number of patent applications in this field indicates a rapid growth trend, mainly in the hands of Shandong Energy Group Co. Ltd., Shandong University of Science and Technology, China University of Mining and Technology, and other institutions or enterprises. Patent technology mainly involves spray dust reduction, dust removal fans, dust masks, and other aspects with high patent value and innovation ability. This article provides a new perspective and reference for preventing, diagnosing, and treating occupational pneumoconiosis in the coal industry.

Association of white matter hyperintensities with low serum 25-hydroxyvitamin D levels

BACKGROUND AND PURPOSE

Vitamin D deficiency is associated with cognitive impairment in the elderly and with increased white matter T2 hyperintensities in elderly debilitated patients. We investigated the relationship between serum vitamin D and brain MR findings in adult outpatients.

MATERIALS AND METHODS

Brain MR studies of 56 patients ages 30-69 years were selected when vitamin D level had been obtained within 90 days of the MRI. White matter T2 hyperintensities were characterized by size and location by two neuroradiologists. Manual volumetric analysis was assessed in patients more than 50 years of age.

RESULTS

The entire cohort showed a significant negative relationship between serum 25-hydroxyvitamin D and the number of confluent juxtacortical white matter T2 hyperintensities (P = .047). The cohort ages 50 years and older showed stronger correlation between confluent white matter T2 hyperintensities and serum 25-hydroxyvitamin D in the juxtacortical region; number (P = .015) and size of white matter T2 hyperintensities (P = .048). Atrophy was not significantly related to serum 25-hydroxyvitamin D by radiologist visual analysis or by the bicaudate ratio.

CONCLUSIONS

We found a significant relationship between vitamin D and white matter T2 hyperintensities in independent adult outpatients, especially over the age of 50 years.

Improvement of enzymatic stability and intestinal permeability of deuterohemin-peptide conjugates by specific multi-site N-methylation

The deuterohemin-peptide conjugate, DhHP-6 (Dh-β-AHTVEK-NH(2)), is a microperoxidase mimetic, which has demonstrated substantial benefits in vivo as a scavenger of reactive oxygen species (ROS). In this study, specific multi-site N-methylated derivatives of DhHP-6 were designed and synthesized to improve metabolic stability and intestinal absorption, which are important factors for oral delivery of therapeutic peptides and proteins. The DhHP-6 derivatives were tested for (1) scavenging potential of hydrogen peroxide (H(2)O(2)); (2) permeability across Caco-2 cell monolayers and everted gut sacs; and (3) enzymatic stability in serum and intestinal homogenate. The results indicated that the activities of the DhHP-6 derivatives were not influenced by N-methylation, and that tri-N-methylation of DhHP-6 could significantly increase intestinal flux, resulting in a two- to threefold higher apparent permeability coefficient. In addition, molecules with N-methylation at selected sites (e.g., Glu residue) showed high resistance against proteolytic degradation in both diluted serum and intestinal preparation, with 50- to 140-fold higher half-life values. These findings suggest that the DhHP-6 derivatives with appropriate N-methylation could retain activity levels equivalent to that of the parent peptide, while showing enhanced intestinal permeability and stability against enzymatic degradation. The tri-N-methylated peptide Dh-β-AH(Me)T(Me)V(Me)EK-NH(2) derived from this study may be developed as a promising candidate for oral administration.

Overexpression of α-2,6 sialyltransferase stimulates propagation of human influenza viruses in Vero cells

Human influenza viruses are major concern as the leading cause of global pandemics. In infecting cells, they preferentially bind to sialyloligosaccharides containing terminal N-acetyl sialic acid linked to galactose by an α-2,6-linkage (NeuAcα2,6Gal). The amount of NeuAcα2,6Gal in Vero cells, which are predominantly used for production of influenza vaccines over the past 30 years, may not be as high as that in epithelial cells of human respiratory tract, what leads to the suboptimal virus growth in Vero cells. In this study, we stably transfected Vero cells with cDNA of human α-2,6-sialyltransferase (SIAT1), an enzyme catalyzing α-2,6-sialylation of galactose on glycoproteins. Overexpression of SIAT1 in the transfected Vero cells (Vero-SIAT1 cells) was confirmed by Western blot analysis and immunofluorescence microscopy. Vero-SIAT1 cells expressed 7 times higher amounts of NeuAcα2,6Gal, but 3 times lower amounts of NeuAcα2,3Gal as compared to parental Vero cells. Furthermore, the influenza viruses A (H1N1 and H3N2) and B grew in Vero-SIAT1 cells to the higher titers than in Vero cells. Taken together, these results imply that Vero-SIAT1 cells are useful not only for the propagation of human influenza viruses, but also for the preparation of influenza vaccines.

Profile of physical status and gene variation of human papillomavirus 58 genome in cervical cancer

Epidemiological studies have shown that human papillomavirus 58 (HPV 58) is found at a relatively high frequency in east Asia and some regions of Central and South America. To investigate the physical status of HPV 58 and analyse sequence variations of HPV 58 in cervical cancer patients, the HPV 58 genome in 37 HPV 58-positive cervical cancer specimens collected from China were investigated by a mapping analysis based on nested PCR and nucleotide sequencing. A pure integrated genome was found in 78.4 % (29/37) of specimens, which is much higher than that found in previous studies. Multiple disruptions were first found among the integrated HPV 58 genomes in 51.7 % (15/29) of specimens. Among the 7824 bp of the HPV 58 genome, 119 (1.52 %) nucleotide positions were found to be variable, and 45 of them lead to amino acid changes. Phylogenetic analyses, based on partial L1 sequences of 14 variants isolated in previous studies and this study, show that two main groups were observed in HPV 58 variants, the prototype or prototype-like group and the non-prototype-like group.

[Studies on antigencity of human immunodeficiency virus type 1 (HIV-1) external glycoprotein as well as its expression in Pichia pastoris]

Based on the computer simulation, we analyzed hydrophobicity, potential epitope of recombined subtypes HIV-1 Env protein (851 amino acids) from Guangxi in China. Compared with conservative peptides of other subtypes in env protein, three sequences (469-511aa, 538-674aa, 700-734aa) were selected to recombine into a chimeric gene that codes three conservative epitope peptides with stronger antigencity, and was constructed in the yeast expression plasmid pPICZB. Chimeric proteins were expressed in Pichia pastoris under the induction of methanol, and were analyzed by SDS-PAGE and Westernblot. The results showed that fusion proteins of three-segment antigen were expressed in Pichia pastoris and that specific protein band at the site of 40kD was target protein, which is interacted with HIV-1 serum. The target proteins were purified by metal Ni-sepharose 4B, and were demonstrated to possess good antigenic specificity from the data of ELISA. This chimeric antigen may be used as research and developed into HIV diagnostic reagents.

HPV prevalence, E6 sequence variation and physical state of HPV16 isolates from patients with cervical cancer in Sichuan, China

OBJECTIVES

Infection with high-risk human papillomavirus (hr-HPV) is an important factor associated with cervical cancer. The genetic mutation of HPV16 E6 and integration of HPV16 DNA in the cervical carcinoma tissues are considered important genetic changes in cervical lesion progression. But the studies of hr-HPV epidemiology are relatively less in the area of Sichuan, China. Therefore, we investigated the prevalence of 9 high-risk subtypes and analyzed the genetic mutation characteristic of HPV16 E6 and physical state of HPV16 DNA.

METHODS

The fragments of L1 and E6 genes were amplified by PCR or nested PCR and then directly sequenced. Further, the multiplex PCR for HPV16 E2 and E6 genes was performed for detection of integration.

RESULTS

HPV16, 58 and 18 were prominent, accounting for 78.6%, 20.0% and 9.7%, respectively in 145 isolates. E6 variants revealed that the European (EP) prototype and East Asia (EA) strain were 26 (23.0%) and 34 (30.1%), respectively. Furthermore, there were 14 base substitutions in E6 regions of the study group, of which 12 resulted in amino acid changes and the rest was silent mutation. Significantly, the 240G substitution exactly located the P53 degradation site. Overall, 8 of 114 (7.0%) isolates only contained integrated HPV16 DNA, 43 (37.7%) only contained episomal DNA and 63 (55.3%) contained both integrated and episomal DNA. The proportion of disruption of an intact E2 gene in the patients with cervical cancer is much lower than that in the previous studies.

CONCLUSIONS

HPV16, 58 and 18 were mainly prevailing subtypes in patients with cervical cancer from Sichuan areas, China and EP/EA strains were predominant in these areas. Some mutations of E6 gene, which lead to the amino acid changes, may be more potentially carcinogenic and the proportion of disruption of an intact E2 gene is much lower.

Biochemical characterization of two mutants of human pyruvate dehydrogenase, F205L and T231A of the E1alpha subunit

Mutations in the E1alpha subunit of the pyruvate dehydrogenase multienzyme complex may result in congenital lactic acidosis, but little is known about the consequences of these mutations at the enzymatic level. Here we characterize two mutants (F205L and T231A) of human pyruvate dehydrogenase in vitro, using the enzyme expressed in Escherichia coli. Wild-type and mutant proteins were purified successfully and their kinetic parameters were measured. F205L shows impaired binding of the thiamin diphosphate cofactor, which may explain why patients carrying this mutation respond to high-dose vitamin B1 therapy. T231A has very low activity and a greatly elevated Km for pyruvate, and this combination of effects would be expected to result in severe lactic acidosis. The results lead to a better understanding of the consequences of these mutations on the functional and structural properties of the enzyme, which may lead to improved therapies for patients carrying these mutations.

Medical image compression by discrete cosine transform spectral similarity strategy

Due to the bandwidth and storage limitations, medical images must be compressed before transmission and storage. However, the compression will reduce the image fidelity, especially when the images are compressed at lower bit rates. The reconstructed images suffer from blocking artifacts and the image quality will be severely degraded under the circumstance of high compression ratios. In this paper, we present a strategy to increase the compression ratio with simple computational burden and excellent decoded quality. We regard the discrete cosine transform as a bandpass filter to decompose a sub-block into equal-sized bands. After a band gathering operation, a high similarity property among bands is found. By the utilization of similarity property, the bit rate of compression can be greatly reduced. Meanwhile, the characteristics of the original image are not sacrificed. Thus, it can avoid the misdiagnosis of diseases for doctors. Simulations are carried to different kind of medical images to demonstrate that the proposed method achieves better performance when compared to other existing transform coding scheme as the JPEG in terms of bit rate and quality. For the case of angiogram image, its peak signal-to-noise-ratio gain is 13.5 dB at the same bit rate of 0.15 bits per pixel when comparing to the JPEG compression. As to the other kind of medical images, their benefits are not so obvious as an angiogram image; however, the gains for them are still from 4-8 dB at high compression ratios. Two doctors from the Department of Radiology, National Cheng Kung University Hospital, Tainan, Taiwan, R.O.C., and Chang Gung Medical Hospital, Kaoshuing, Taiwan, R.O.C., are invited to verify the decoded image quality; the diagnoses of all the test images are correct when the compression ratios are below 20.

Congenital lactic acidosis: evaluation of the properties of the a199t natural variant of human pyruvate dehydrogenase e1alpha by in vitro mutation

One cause of congenital lactic acidosis is a mutation in the E1 alpha-subunit of the pyruvate dehydrogenase multienzyme complex. Little is known about the consequences of these mutations at the enzymatic level. Here we study the A199T mutation by expressing the protein in Escherichia coli. The specific activity is 25% of normal and the K(m) for pyruvate is elevated by 10-fold. Inhibitors of lactate dehydrogenase might be a useful therapy for patients with such mutations.

Mutagenesis at asp27 of pyruvate decarboxylase from Zymomonas mobilis. Effect on its ability to form acetoin and acetolactate

Pyruvate decarboxylase (PDC) is one of several enzymes that require thiamin diphosphate (ThDP) and a bivalent cation as essential cofactors. The three-dimensional structure of PDC from Zymomonas mobilis (ZMPDC) shows that Asp27 (D27) is close to ThDP in the active site, and mutagenesis of this residue has suggested that it participates in catalysis. The normal product of the PDC reaction is acetaldehyde but it is known that the enzyme can also form acetoin as a by-product from the hydroxyethyl-ThDP reaction intermediate. This study focuses on the role of D27 in the production of acetoin and a second by-product, acetolactate. D27 in ZMPDC was altered to alanine (D27A) and this mutated protein, the wild-type, and two other previously constructed PDC mutants (D27E and D27N) were expressed and purified. Determination of the kinetic properties of D27A showed that the affinity of D27A for ThDP is decreased 30-fold, while the affinity for Mg2+ and the Michaelis constant for pyruvate were similar to those of the wild-type. The time-courses of their reactions were investigated. Each mutant has greatly reduced ability to produce acetaldehyde and acetoin compared with the wild-type PDC. However, the effect of these mutations on acetaldehyde production is greater than that on acetoin formation. The D27A mutant can also form acetolactate, whereas neither of the other mutants, nor the wild-type PDC, can do so. In addition, acetaldehyde formation and/or release are reversible in wild-type ZMPDC but irreversible for the mutants. The results are explained by a mechanism involving thermodynamic and geometric characteristics of the intermediates in the reaction.

An adaptive 3-D discrete cosine transform coder for medical image compression

In this communication, a new three-dimensional (3-D) discrete cosine transform (DCT) coder for medical images is presented. In the proposed method, a segmentation technique based on the local energy magnitude is used to segment subblocks of the image into different energy levels. Then, those subblocks with the same energy level are gathered to form a 3-D cuboid. Finally, 3-D DCT is employed to compress the 3-D cuboid individually. Simulation results show that the reconstructed images achieve a bit rate lower than 0.25 bit per pixel even when the compression ratios are higher than 35. As compared with the results by JPEG and other strategies, it is found that the proposed method achieves better qualities of decoded images than by JPEG and the other strategies.

Measurement of the total cross section for hadronic production by e(+)e(-) annihilation at energies between 2.6-5 GeV

Using the upgraded Beijing Spectrometer, we have measured the total cross section for e(+)e(-) annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6, and 5.0 GeV. Values of R, sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->&mgr;(+)&mgr;(-)), are determined.

Laboratory evaluation on the toxic effects of bednets impregnated with permethrin against malaria mosquitos

In the laboratory, bednets impregnated with 250mg ai/m2 and 500mg ai/m2 permethrin caused respectively the mean mortalities of 86.6% within 13 months and 87.2% within 17 months on laboratory-bred An. sinensis, while they caused average mortalities of 58.3% within 4 months and 73.8% within 10 months on An. dirus respectively. The bioassay results of KT50 and LT50 on the two species showed that KT50 is shorter than LT50 after exposure to the treated bednets. The ratio is 1:2.16 - 1:3.05. It was observed Anopheles had obviously secondary knocked down after exposure to the treated bednets and there is obvious resurgent after Anopheles have been knocked down. When the temperature goes up the resurgence gets shorter, the resurgence rate gets higher and the mortality gets lower. It showed that permethrin has stronger knocking down effect than killing effect.

[Application of microsurgical technique in the intrasinus renalis pyeloureteroplasty in pelvic atresia in children]

Seven cases of pelvic atresia in children were treated by the intrasinus renalis pyeloureteroplasty with the application of microsurgical technique. The site of pelviureteric anastomosis was unobstructed and the hydronephrosis was greatly improved through postoperative examinations of intravenous urography and renogram. This procedure provides clear field, simple performance and high successful rate. The prevention of complete pelviureteric laceration and pelvic atresia in children, the advantages of the microsurgical technique, and the operation precautions are discussed.

Experimental studies on peripheral nerve regeneration enhanced by nerve growth factor

The effect of exogenous nerve growth factor (NGF) examined on the neural repair of adult rabbit sciatic nerve was evaluated in the present study. A nerve regeneration chamber was created by suturing the proximal and distal ends of a transected sciatic nerve into a silicone chamber. A gap of 6 mm in chamber was left after removal of a 3 mm piece of nerve in the distal ends and insertion of the proximal and distal stumps into the chamber. Animals were operated on bilaterally, one side of the chamber was filled with a 1 mg/ml NGF/normal saline (NS) (experimental) and the contralateral side with NS (control). The regenerated nerves from within the silicone chamber were dissected and fixed 1 to 5 weeks following surgery for histological studies at both the light microscopic and ultrastructural levels. The NGF chamber showed a more mature regenerated nerve based on a larger diameter of the regenerated nerve trunk, a great number of axons, and thicker myelin sheaths.

Clinical application of the forearm island skin and fascia flap with posterior interosseous artery pedicle--report of 15 cases

The present paper reported 15 cases, in which skin and fascia forearm island flap with posterior interosseous artery pedicle was applied. It was found that this flap has the advantages of stable vessels, abundance in blood supply and good circulation, without sacrificing the main arteries of the forearm. As a result, it is an ideal method for repair and reconstruction of the hand and forearm.