[Occupational health risk assessment for organic solvent in the major posts of printing industry].

Objective: To evaluate the occupational health risk of organic solvents in major posts of printing industry, and to provide technical reference to take targeted risk control measures. Methods: In January 2021, the contact ratio method was used to assess the occupational health risk of organic solvents in the major posts of 84 printing enterprises in Shantou, and Monte Carto method was used to estimate the probability distribution of risk levels in the majorpostsin January 2021. Results: The highest probability of risk assessment in printing and membranecovering post is Level 4 (high risk) , which are 76.2% and 67.6% respectively; the highest probability of simulation evaluation result in oil blending, dispensing and cleaning post is Level 3 (medium risk) ; and the simulation evaluation result in glueing post are mostly Level 3 (medium risk) and Level 4 (high risk) , the probability of which are 45.7% and 54.3% respectively. Conclusion: The occupational health risk of organic solvents in the major posts is generally middle-high risk level, and then the occupational health risk control of organic solvents in major posts of printing industry should be strengthened.

[Isolated biceps tenodesis by double row for pulley lesions].

Objective: To explore clinical outcome of isolated arthroscopic biceps tenodesis by double row for pulley lesions. Methods: Forty-nine patients with pulley lesions were treated from July 2017 to June 2018 in the Department of Sport Medicine, the Affiliated Zhongshan Hospital of Dalian University by isolated arthroscopic biceps tenodesis by double row. Patients were divided into 2 groups according to the intraoperative damage of the pulley system. In group A, there were 16 patients with isolated superior glenohumeral ligament/coracohumeral ligament (SGHL/CHL) complex lesions, including 9 males and 7 females, aged (55±6) years. In group B, there were 33 patients (15 males and 18 females, aged (57±8) years) with SGHL/CHL complex and adjacent supraspinatus tendon and/or subscapularis tendon articular-side partly tears. Patients in two groups were treated with different isolated arthroscopic biceps tenodesis by double row. Constant-Murley shoulder score and pain visual analogue scale (VAS) score were assessed before operation and 3, 6, 12 months after the operation. Postoperative complications were also recorded in two groups. The t test was used to compare the quantitative data within and between two groups. Results: All 49 patients were followed up for 12 to 24 months with an average of (17±6) months. The first-stage healing was achieved in all incisions in the two groups. No surgical complications related to revision, infection, Popeye syndrome and cramping pain were observed in either group. There was 1 case treated by secondary arthroscopy for retrauma in group B. The Constant-Murley shoulder score in group A before the operation was 46±10, and it was increased to 89±9 at the 12 months post operation(t=-22.637, P<0.05); and it was 39±10 and 87±8 before and 12 months after the operation respectively in group B (t=-44.849, P<0.05). The VAS scores in the two groups were both decreased significantly at the 12 months post operation when compared with those before the operation (0.68±0.70 vs 5.25±0.27 and 0.72±0.83 vs 5.69±0.84, respectively) (t=29.007, 37.079, both P<0.05). Conclusion: Isolated arthroscopic biceps tenodesis by double row can relieve pain, recover functions of shoulder joint effectively, and achieve a satisfactory outcome in the treatment of pulley lesions.

An incremental feeding pattern for Guangdong Small-ear Spotted gilts during gestation: effects on stillbirth rate and muscle weight of progeny.

While an appropriate feed intake is crucial for the reproductive performance of sows, there is a lack of recommendations currently for feed allowance of Guangdong Small-ear Spotted gilts during gestation. The effects of 2 different feeding patterns during gestation on the reproductive performance of Guangdong Small-ear Spotted gilts were investigated by assigning 80 gilts to 2 feeding pattern groups with a randomized complete block design in accordance with initial body weight and back fat thickness, followed by treatment with an incremental feeding pattern (IFP) and a concaved feeding pattern, respectively, with no difference in total feed intake. The IFP group showed a significant decrease in the stillbirth rate (P < 0.05) and an upward trend in piglet mean birth weight (P = 0.06). Furthermore, the IFP group exhibited an increase in the weights of stomach, supraspinatus tendon, triceps, and psoas minor in neonatal piglets (P < 0.05). Overall, the results of the present investigation showed that IFP could significantly reduce the stillbirth rate of Guangdong Small-ear Spotted gilts and increase the muscle weight of progeny.

[Effects and mechanisms of allogeneic epidermal stem cells on the survival of allogeneic full-thickness skin grafts in nude mice with full-thickness skin defect wounds].

Objective: To investigate the effects and mechanisms of allogeneic epidermal stem cells (ESCs) on the survival of allogeneic full-thickness skin grafts in nude mice with full-thickness skin defect wounds. Methods: Experimental research methods were applied. Primary ESCs that appeared paving stone-like after being cultured for 7 d were obtained by enzymatic digestion method from one 4-week-old male BALB/c-NU nude mouse (the same strain, age, and sex below). The cells of third passage were identified by flow cytometry to positively express ESC marker CD44 and negatively express CD45, meanwhile, the positive expression of ESC markers of p63 and integrin 6α, and negative expression of CD71 were identified by immunofluorescence method. The ESCs of third passage in the logarithmic growth phase were used for the following experiments. Twenty-six nude mice were equally divided into phosphate buffered saline (PBS) group and ESCs group according to the random number table. A full-thickness skin defect wound was made on the back of each nude mouse, and then the wounds of the two groups were sprayed with equal volumes of PBS and ESCs, respectively. The wounds were transplanted with full-thickness skin grafts cut from the backs of 4 other nude mice. Each ten nude mice from the two groups were selected, the wound healing and skin survival on post surgery day (PSD) 0 (immediately), 3, 7, 14, and 21 were observed, and the survival ratio and shrinkage rate of skin grafts on PSD 3, 7, 14, and 21 were calculated (the number of sample was the number of surviving skin grafts at each time point); the blood perfusion in the skin grafts on PSD 3, 7, and 14 was detected by the laser speckle blood flow imager, and the blood flow ratio of nude mice skin grafts in ESCs group to PBS group at each time point was calculated (the number of sample was the pair number of surviving skin grafts in group pairing at each time point). The skin graft tissue of each 3 nude mice remained in the two groups were collected on PSD 7, and the mRNA expressions and protein expressions of tumor necrosis factor α (TNF-α), interleukin 8 (IL-8), IL-10, type Ⅰ collagen, type Ⅲ collagen, and matrix metalloproteinase 9 (MMP-9) in the tissue were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Data were statistically analyzed with Log-rank test, analysis of variance for repeated measurement, one-way analysis of variance, independent sample t test, and Bonferroni correction. Results: Taking the condition on PSD 0 as a reference, the wounds of nude mice in the two groups healed gradually on PSD 3, 7, 14, and 21, and the shrinkage of skin grafts was gradually obvious. Among them, the shrinkage healing of wound of nude mice in PBS group was more significant than that in ESCs group. On PSD 3, the skin graft of 1 nude mouse failed in ESCs group, while the skin graft of 3 nude mice failed in PBS group. On PSD 7, the skin graft of another nude mouse failed in PBS group. The survival ratio of skin grafts of nude mice in the two groups was similar on PSD 3, 7, 14, and 21 (P>0.05). On PSD 3, 7, 14, and 21, the shrinkage rates of skin grafts of nude mice in ESCs group were (9.2±0.4)%, (19.7±1.2)%, (53.6±3.5)%, and (62.2±5.1)%, respectively, which was significantly lower than (11.0±0.9)%, (47.8±2.8)%, (86.1±7.1)%, and (89.7±9.0)% in PBS group (t=5.719, 26.650, 11.940, 7.617, P<0.01). On PSD 3, 7, and 14, blood perfusion signals were observed in the skin grafts of nude mice in the two groups. The average blood perfusion ratios of the skin grafts of nude mice in ESCs group to PBS group were greater than 1, and there was no statistically significant difference in the overall comparison of 3 time points (P>0.05). On PSD 7, compared with those of PBS group, the mRNA and protein expressions of TNF-α, IL-8, type Ⅰ collagen, and type Ⅲ collagen in the skin graft tissue of nude mice in ESCs group were significantly reduced, while the mRNA and protein expressions of IL-10 and MMP-9 in the skin graft tissue of nude mice in ESCs group were significantly increased (in mRNA comparison, t=2.823, 2.934, 2.845, 2.860, 3.877, 2.916, P<0.05). Conclusions: Allogeneic ESCs can reduce the shrinkage of allogeneic full-thickness skin grafts transplanted on full-thickness skin defect wounds in nude mice, promote the formation of new blood vessels between the skin graft and the wound, reduce inflammation and collagen protein expression, and promote the expression of MMP-9, thus improving the survival quality of skin grafts.

[Progress of research on the relations between bipolar disorder and type 2 diabetes mellitus].

Both risks of type 2 diabetes mellitus (T2DM) in patients with bipolar disorder (BD) and of BD in patients with T2DM are both significantly higher than the general population, indicating the two disorders may share the common pathogenesis. Patients with BD and co-morbid T2DM behave poorly on managing their own behavior on health, thus increased risks of outcomes on related complications, disability and mortality. The article reviewed the epidemiologic features, health hazards, relations and possible mechanisms between BD and T2DM. Strategies and measures on intervention of BD and T2DM were also involved in the text to improve the awareness and research ability of the researchers.

SIRT2 inhibits oxidative stress and inflammatory response in diabetic osteoarthritis.

OBJECTIVE: Diabetes mellitus is involved in inflammation, immunity, and metabolism during osteoarthritis (OA). It destroys the normal synthesis and degradation balance of chondrocytes (CHs) and extracellular matrix (ECM). The purpose of this study was to explore the possible way of SIRT2 influencing the progress of diabetic OA. PATIENTS AND METHODS: Proteins of diabetic OA and normal OA cartilage samples were extracted from patients undergoing knee joint operation. CHs were also isolated from the cartilage exempted from diabetes for cell culture. Glucose was used to treat CHs for imitating the microenvironment of diabetes. The expressions of SIRT2, acetylated H3K9, H3K14, and H3K56 protein were determined by Western blotting. SIRT2, 8-hydroxy-2' deoxyguanosine (8-OH), and MMP-13 expressions were analyzed using immunofluorescence. RT-PCR was performed to measure the mRNA levels of SOD1, SOD2, CAT, MMP-13, ADAMTS-4, and ADAMTS-5. Total ROS level was performed by flow cytometry assay. RESULTS: SIRT2 expression was reduced, whereas acetylated H3K9, H3K14, and H3K56 were upregulated in diabetic cartilage compared to normal. High glucose suppressed the expression of SIRT2 but accelerated the acetylation of H3K9, H3K14, and H3K56. Besides, high glucose promoted the expression of 8-OH, and inhibited SOD1, SOD2, and CAT mRNA expressions, resulting in the up-regulated ROS level of CHs. In addition, high glucose activated the inflammatory response by upregulation of MMP-13, ADAMTS-4, and ADAMTS-5 expressions. SirReal2 suppressed SIRT2 and resulted in several acetylations of H3, more ROS, less antioxidant enzymes, and stronger inflammatory response caused by high glucose. However, supplied rh-SIRT2 reversed these negative effects of high glucose in CHs. CONCLUSIONS: SIRT2 expression is reduced along with the diabetic OA process with increased acetylation of H3, oxidative stress, and inflammatory response. Suppression of SIRT2 accelerates the progress of diabetic OA and upregulation of SIRT2 alleviates diabetic OA development by suppressing oxidative stress and inflammatory response that are likely to be related to the deacetylation of H3.

AKT-GSK3ß Signaling Pathway Regulates Mitochondrial Dysfunction-Associated OPA1 Cleavage Contributing to Osteoblast Apoptosis: Preventative Effects of Hydroxytyrosol.

Oxidative stress (OS) induces osteoblast apoptosis, which plays a crucial role in the initiation and progression of osteoporosis. Although OS is closely associated with mitochondrial dysfunction, detailed mitochondrial mechanisms underlying OS-induced osteoblast apoptosis have not been thoroughly elucidated to date. In the present study, we found that mitochondrial abnormalities largely contributed to OS-induced osteoblast apoptosis, as evidenced by enhanced production of mitochondrial reactive oxygen species; considerable reduction in mitochondrial respiratory chain complex activity, mitochondrial membrane potential, and adenosine triphosphate production; abnormality in mitochondrial morphology; and alteration of mitochondrial dynamics. These mitochondrial abnormalities were primarily mediated by an imbalance in mitochondrial fusion and fission through a protein kinase B- (AKT-) glycogen synthase kinase 3ß- (GSK3ß-) optic atrophy 1- (OPA1-) dependent mechanism. Hydroxytyrosol (3,4-dihydroxyphenylethanol (HT)), an important compound in virgin olive oil, significantly prevented OS-induced osteoblast apoptosis. Specifically, HT inhibited OS-induced mitochondrial dysfunction by decreasing OPA1 cleavage and by increasing AKT and GSK3ß phosphorylation. Together, our results indicate that the AKT-GSK3ß signaling pathway regulates mitochondrial dysfunction-associated OPA1 cleavage, which may contribute to OS-induced osteoblast apoptosis. Moreover, our results suggest that HT could be an effective nutrient for preventing osteoporosis development.

RAGE-dependent mitochondria pathway: a novel target of silibinin against apoptosis of osteoblastic cells induced by advanced glycation end products.

Advanced glycation end products (AGEs) can stimulate osteoblast apoptosis and have a critical role in the pathophysiology of diabetic osteoporosis. Mitochondrial abnormalities are closely related to osteoblast dysfunction. However, it remains unclear whether mitochondrial abnormalities are involved in AGE-induced osteoblastic cell apoptosis. Silibinin, a major flavonolignan compound of silimarin, has strong antioxidant and mitochondria-protective properties. In the present study, we explored the possible mitochondrial mechanisms underlying AGE-induced apoptosis of osteoblastic cells and the effect of silibinin on osteoblastic cell apoptosis. We demonstrated that mitochondrial abnormalities largely contributed to AGE-induced apoptosis of osteoblastic cells, as evidenced by enhanced mitochondrial oxidative stress, conspicuous reduction in mitochondrial membrane potential and adenosine triphosphate production, abnormal mitochondrial morphology, and altered mitochondrial dynamics. These AGE-induced mitochondrial abnormalities were mainly mediated by the receptor of AGEs (RAGE). In addition, we found that silibinin directly downregulated the expression of RAGE and modulated RAGE-mediated mitochondrial pathways, thereby preventing AGE-induced apoptosis of osteoblastic cells. This study not only provides a new insight into the mitochondrial mechanisms underlying AGE-induced osteoblastic cell apoptosis, but also lays a foundation for the clinical use of silibinin for the prevention or treatment of diabetic osteoporosis.

Fluconazole susceptibility of 3,056 clinical isolates of Candida species from 2005 to 2009 in a tertiary-care hospital.

In recent years, Candida infections have been increasing significantly. This study was to investigate the distribution and fluconazole susceptibility of such infections. Totally, 3,056 clinical isolates were analysed, C. albicans was the most prevalent species from respiratory and vaginal specimens. However, non-albicans species constituted the majority of isolates from blood, urine, intensive care unit (ICU), organ transplant and burned patients. Similarly, Candida spp. from different specimens and clinical services had different degrees of susceptibility to fluconazole. Isolates from vagina and burned patients had the highest resistance rate, while all of the isolates from ascites and dermatological services were susceptible to fluconazole.

[Seronegative synovitis syndrome].

3 cases of seronegative synovitis syndrome were reported. Two elderly women and one man presented with symmetrical polysynovitis of acute onset involving most of their appendicular joints and flexor digitorum tendons associated with pitting edema of the dorsum of both hands and both feet. Rheumatoid factor was absent from serum samples in all and no radiologically evident erosions developed. All the three patients had a benign course and the disease resolved completely within 2-18 months after the onset. None had deformities, erosions and/or relapse after being followed for 22-34 months. Literatures on this syndrome were reviewed.

The CPP-ACP relieved enamel erosion from a carbonated soft beverage: an in vitro AFM and XRD study.

OBJECTIVES: To investigate the CPP-ACP's effect on enamel against carbonated beverage erosion and explore the potential mechanism. METHODS: A total of 30 enamel samples were prepared from sound bovine incisors, divided into 3 groups. Samples in the control group were kept in artificial saliva. Specimens' surfaces were smeared with a CPP-ACP agent (Tooth Mousse, TM) for 3 min, rinsed with distilled water for 10s, merged into cola (Coca Cola, CC) for 4 intervals of 2 min, rinsed again for the TM+CC group. In the CC group, specimens were treated solely with cola for 4 intervals (2 min each). The cycles were applied at 0, 12, 24, 36, 48 and 60 h. The surface microhardness (SMH) alterations were measured using a microhardness tester, the surface profiles were analyzed using the atomic force microscope, and the surface crystalline amount (I%) and crystallinity (FWHM) were analyzed using X-ray diffractometer. RESULTS: The SMH were significantly decreased in CC group, showing the largest SMH alteration; the reduction of SMH in TM+CC group was lower than that in CC group, still larger than control. After cycles, the TM+CC group showed rougher surfaces than control, while the CC group had the roughest surfaces. The TM+CC had an I% higher than the CC, and lower than the control. The TM+CC group had a FWHM lower than CC, higher than control. CONCLUSIONS: CPP-ACP was able to relieve the erosion on enamel from carbonated beverage.

Effect of nano-hydroxyapatite concentration on remineralization of initial enamel lesion in vitro.

The purpose of the research was to determine the effect of nano-hydroxyapatite concentrations on initial enamel lesions under dynamic pH-cycling conditions. Initial enamel lesions were prepared in bovine enamel with an acidic buffer. NaF (positive control), deionized water (negative control) and four different concentrations of nano-hydroxyapatite (1%, 5%, 10% and 15% wt%) were selected as the treatment agents. Surface microhardness (SMH) measurements were performed before/after demineralization and after 3, 6, 9 and 12 days of application, and the percentage surface microhardness recovery (%SMHR) was calculated. The specimens were then examined by a scanning electron microscope. The %SMHR in nano-hydroxyapatite groups was significantly greater than that of negative control. When the concentration of nano-HA was under 10%, SMH and %SMHR increased with increasing nano-hydroxyapatite concentrations. There were no significant differences between the 10% and 15% groups at different time periods in the pH-cycling. The SEM analysis showed that nano-hydroxyapatite particles were regularly deposited on the cellular structure of the demineralized enamel surface, which appeared to form new surface layers. It was concluded that nano-hydroxyapatite had the potential to remineralize initial enamel lesions. A concentration of 10% nano-hydroxyapatite may be optimal for remineralization of early enamel caries.

Effect of gallic acid on the wear behavior of early carious enamel.

The purpose of this research was to investigate the wear behavior of early carious enamel remineralized with gallic acid. Forty natural human premolar specimens with early caries lesions were prepared. A remineralization pH-cycling treatment agent of 4000 ppm gallic acid was used for 12 days to treat the early lesions. The changes in microhardness were monitored. Nanoscratch tests were used to evaluate wear resistance. The experimental data were analyzed by using a t-test. The widths of traces were measured by an AMBIOS XP-2 stylus profilometer. After remineralization, all samples re-hardened significantly. The coefficients of friction became higher, and the widths of scratches were larger than they were before remineralization. Gallic acid significantly improved the early carious enamel's hardness. The wear damage of the samples treated with gallic acid was more severe than that of the control group. There were more obvious cracks and delaminations on the traces of the treated group. Compared with the control group, the enamel remineralized with gallic acid had inferior wear resistance. After remineralization, the dominant damage mechanisms of early carious enamel had changed from plastic deformation and adhesive wear to a combination of brittle cracks and delamination of enamel.

Calibration of bone mineral and heavy metal measurements using doped wall-less gel phantoms of arbitrary form.

Cylindrical gel phantoms of 2% agarose concentration were used as wall-less phantoms of arbitrary shape for calibration purposes in non-destructive measurements of bone mineral and heavy metal concentration using XRF. The counts of the coherently and incoherently scattered photons with no sample present should be subtracted as "background" to get a linear relationship between the ratio of the coherently and incoherently scattered photons and the bone mineral concentration for phantoms of arbitrary diameters.

A specificity comparison of four antisense types: morpholino, 2'-O-methyl RNA, DNA, and phosphorothioate DNA.

Cell-free translation studies were carried out to compare the efficacy and specificity of four antisense structural types: DNA, phosphorothioate DNA (S-DNA), 2'-O-methyl RNA, and Morpholino oligos, a novel antisense structural type. In these studies, translational inhibition was assessed for two 20-mers of each structural type, where one 20-mer was complementary to its target sequence in rabbit alpha-globin mRNA and the other 20-mer contained three mispairs to that same target sequence. It is shown that at low concentration of antisense oligomer (50 nM) all four types provide high specificity, but the Morpholino oligos and 2'-O-methyl RNA afford better efficacy. At high oligomer concentration (3.5 microM), all four types provide high efficacy, but the Morpholino oligos and 2'-O-methyl RNA provide substantially better specificity than the DNA and S-DNA.

Morpholino and phosphorothioate antisense oligomers compared in cell-free and in-cell systems.

Morpholino and phosphorothioate (S-DNA) antisense oligos were compared in both cell-free and in-cell translation systems. In the most stringent test of specificity in the cell-free system, a globin-targeted S-DNA oligo was found to inhibit its target sequence at concentrations of 10 nM and above, but the sequence-specific component of this inhibition dropped below 50% at concentrations of 100 nM and above. A corresponding Morpholino oligo achieved even higher inhibition at 10 nM, but in contrast to the S-DNA, with the Morpholino, the sequence-specific component of this inhibition remained above 93% at a concentration of 3000 nM. In this same cell-free test system, several S-DNA oligos exhibited substantial undesired nonantisense effects at concentrations of 300 nM and above, whereas corresponding Morpholino oligos exhibited little or no nonantisense activity through a concentration of 3000 nM. In scrape-loaded HeLa cells, both globin-targeted and HBV-targeted S-DNAs (both antisense and control oligos) generally failed to achieve significant translational inhibition at extracellular concentrations up to 3000 nM. In contrast, the Morpholino oligos achieved effective and specific translational inhibition at extracellular concentrations ranging from 30 nM to 3000 nM.

Stacking interactions of ApA analogues with modified backbones.

CD spectra have been measured as a function of temperature for a number of ApA analogues with modified backbones. Oligonucleotides with these modified backbones are being used as antisense agents having potential as viral therapeutics. Results of these studies show that when a carbonyl is substituted for the phosphate to produce an uncharged backbone, the analogues that have either sugar or morpholino substitution do not stack. In contrast, when a morpholino group is substituted for the sugar and the phosphate is modified so as to be uncharged, there is strong base stacking. Stacking interactions in the phosphorus-linked morpholino analogues are at least as strong as those found in d(ApA). The stacking interactions in ApA are weak by comparison. Singular value decomposition demonstrates that the stacking is two state, and Taylor series decomposition yields a coefficient that measures base stacking interactions. The van't Hoff equation is applied to the base stacking coefficient from the Taylor series fitting to give thermodynamic parameters.

Resistance of morpholino phosphorodiamidate oligomers to enzymatic degradation.

Oligomers possessing the Morpholino phosphorodiamidate backbone were evaluated for resistance to a variety of enzymes and biologic fluids. A 25-mer was incubated with nucleases, proteases, esterases, and serum, and the reaction mixtures were directly analyzed by MALDI-TOF mass spectrometry. The 25-mer was completely resistant to 13 different hydrolases and serum and plasma. The excellent resistance of Morpholino phosphorodiamidates to enzymatic attack indicates their suitability for in vivo use.