[Interaction of polycyclic aromatic hydrocarbon DNA adducts and telomere length on missed abortion].

Objective: To analyze the contribution and interaction of polycyclic aromatic hydrocarbons (PAH)-DNA adducts and changes of telomere length (TL) on missed abortion. Methods: From March to December 2019, patients with missed abortion in the First Hospital of Shanxi Medical University and pregnant women with normal pregnancy but voluntary abortion in the same department during the same period were selected and divided into a case group and a control group. Questionnaire was used to investigate the general situation and the pregnancy situation of the subjects. The abortion villi were collected and the content of PAH-DNA adducts and TL was detected. Logistic regression model was used to analyze the associated factors of missed abortion. R epiR package and Mediation package were used to analyze the effect and relationship between PAH-DNA adducts and TL on missed abortion. Results: The age of the subjects was(29.92±5.69)years old. The M(Q1,Q3)of PAH-DNA adducts was 453.75(404.61, 504.72) pg/ml. The M(Q1,Q3)of TL was 1.21(0.77, 1.72). The content of PAH-DNA adducts in the case group was higher than that in the control group (Z=-2.10, P=0.036), while the TL was lower than that in the control group (Z=-4.05, P<0.001). Multivariate logistic regression showed that low, medium and high levels of PAH-DNA adducts (OR=3.17,95%CI:1.41-7.14;OR=2.85,95%CI:1.25-6.52;OR=2.46,95%CI:1.07-5.64), and long, medium and short levels of TL (OR=2.50,95%CI:1.11-5.63;OR=3.32,95%CI:1.45-7.56;OR=3.22,95%CI:1.42-7.26) were all risk factors for missed abortion. The medium level of PAH-DNA adducts had a 2.76-fold higher risk of shortened TL than those with the lowest level, and no mediating role of TL was found. The stratified analysis showed that when the TL level was longer (>1.21), the low and high levels of PAH-DNA adducts were associated with missed abortion (all P<0.05); when the TL level was shorter (<1.21), the medium level of PAH-DNA adducts was associated with abortion (P=0.025). At lower levels of PAH-DNA adducts, no effect of TL on missed abortion was observed, while, at higher levels, TL was strongly associated with missed abortion (OR=7.50,95%CI:1.95-28.82;OR=6.04,95%CI:1.54-23.65;OR=9.05,95%CI:2.34-35.04). The interaction analysis found that the AP was 0.72 (95%CI: 0.46-0.99), and the SI was 5.21 (95%CI: 2.30-11.77). Conclusion: The high level of PAH-DNA adducts and shortened TL may increase the risk of missed abortion, and there may be a positive additive interaction between the two factors on missed abortion.

[The moderating effect analysis of mindfulness on perceived stress and job burnout of medical staff].

Objective: To explore the moderating mechanism of mindfulness on perceived stress and job burnout of medical staff. Methods: From November 2020 to March 2022, 1626 medical staff were investigated by questionnaires. Chinese Version Perceived Stress Scale (CPSS), Maslach Burnout Inventory-Human Service Survey (MBI-HSS) and Mindful Attention Awareness Scale (MAAS) were used to evaluate the perceived stress, three dimensions of job burnout[depersonalization (DP), emotional exhaustion (EE), personal accomplishment (PA) ], and mindfulness level of medical staff. The Spearman rank correlation analysis was used to analyze the correlation between mindfulness and perceived stress, job burnout of medical staff. And the SPSS PROCESS macro program was used to test the moderating effect of mindfulness on perceived stress and job burnout. Results: Among the 1626 medical staff, 57.38% had perceived stress with health risk (933/1626), and 63.84% (1038/1626) had job burnout, among them, with 618 (38.01%), 274 (16.85%), and 146 (8.98%) experiencing mild, moderate and severe job burnout, respectively. The scores of mindfulness among medical staff were significantly correlated with perceived stress and various dimensions of job burnout (EE, DP and PA) (r(s)=-0.155, -0.351, -0.315, 0.307, P<0.001). Mindfulness had a moderating effect between perceived stress and job burnout, which was achieved through three moderating pathways: perceived stress-mindfulness-EE, perceived stress-mindfulness-DP and perceived stress-mindfulness-PA (ΔR(2)=0.073, 0.06, 0.006, P<0.001) . Conclusion: Medical staff have a high level of job burnout, mindfulness plays a moderating role between perceived stress and job burnout. Specific measures can be taken to improve the level of mindfulness in medical staff, so as to prevent and alleviate job burnout of medical staff.

Relationship between fasting plasma glucose and incidence of diabetes in children and adolescents.

AIM: To investigate the appropriate fasting plasma glucose threshold by which to define prediabetes in children and adolescents, based on its ability to predict incident paediatric diabetes. METHODS: In a nationwide survey of diabetes and renal disease conducted between 1992 and 2000 in all school-aged children in Taiwan, those with abnormal results in repeated urine tests received further physical examination and blood tests. Students who had blood tests for at least two time points were selected for the present study (N = 12 119). The incidence of paediatric diabetes, adjusted hazard ratio and predictive power of fasting plasma glucose were analysed. RESULTS: The incidence of paediatric diabetes increased with increasing fasting plasma glucose levels. Groups with fasting plasma glucose >5.6 mmol/l had a higher adjusted hazard ratio. The adjusted hazard ratio of incident diabetes for participants with higher fasting plasma glucose rose continuously when using a higher threshold for fasting plasma glucose. The area under the receiver-operating characteristic curve for fasting plasma glucose was 0.628 for predicting paediatric diabetes. The association between fasting plasma glucose and incident paediatric diabetes and the area under the receiver-operating characteristic curve were similar in boys and girls and were higher in the age group 12-18 years. According to receiver-operating characteristic curve analysis, the optimal thresholds, sensitivity and specificity were 4.75 mmol/l, 65% and 51%, respectively, for those aged 6-11 years and 5.19 mmol/l, 60% and 73%, respectively, for those aged 12-18 years. CONCLUSION: Fasting plasma glucose is associated with the incidence of paediatric diabetes. The results of the present study can be used as reference data to suggest a cut-off value to define paediatric prediabetes.

Hypoxia regulates sumoylation pathways in intervertebral disc cells: implications for hypoxic adaptations.

OBJECTIVE: To explore the hypoxic regulation of sumoylation pathways and cell viability in nucleus pulposus (NP) and annulus fibrosus (AF) cells. DESIGN: Expression of small ubiquitin-like modifier (SUMO) molecules, SUMO E1 activating enzymes SAE1 and SAE2, SUMO E2 conjugating enzyme UBC9, and de-sumoylation enzyme sentrin/SUMO-specific proteases (SENP)1 was immunolocalized in rat intervertebral disc (IVD) cells. NP and AF cells were cultured in hypoxia and cell viability was evaluated by quantifying cell proliferation, cellular senescence, apoptosis, and cell cycle distribution. Hypoxic regulation of sumoylation pathways was studied by analyzing the transcription and expression of SUMO molecules and sumoylation enzymes. Loss of function study using SENP1 siRNA was performed to investigate the regulatory role of sumoylation on the function of hypoxia inducible factor 1α (HIF-1α) and the hypoxic tolerance of IVD cells. RESULTS: Sumoylation pathways were expressed in IVD cells and localized predominantly in nuclei. Both NP and AF cells maintained viability under hypoxia and upregulated the expression of SENP1. In NP cells hypoxia transiently increased the expression of SUMO-1, SUMO-2/3, SAE2, and UBC9, whereas SUMO-1 was elevated while SUMO-2/3, SAE1, SAE2, and UBC9 were reduced by low oxygen tensions in AF cells. Although downregulation of SENP1 decreased the transcriptional activity of HIF-1α, the viability of disc cells showed no significant loss under hypoxia. CONCLUSIONS: NP and AF cells equally tolerate oxygen deficiency, but differently regulate the sumoylation pathways under hypoxia. The distinct sumoylation dynamics may help extend our understanding of the cell-specific regulation of the molecular basis that promotes cell survival in the hypoxic IVD.

Performance of homeostasis model assessment and serum high-sensitivity C-reactive protein for prediction of isolated post-load hyperglycaemia.

AIMS: To evaluate whether homeostasis model assessment and high-sensitivity C-reactive protein improve the prediction of isolated post-load hyperglycaemia. METHODS: The subjects were 1458 adults without self-reported diabetes recruited between 2006 and 2010. Isolated post-load hyperglycaemia was defined as fasting plasma glucose < 7 mmol/l and 2-h post-load plasma glucose ≥ 11.1 mmol/l. Risk scores of isolated post-load hyperglycaemia were constructed by multivariate logistic regression. An independent group (n = 154) was enrolled from 2010 to 2011 to validate the models' performance. RESULTS: One hundred and twenty-three subjects (8.28%) were newly diagnosed as having diabetes mellitus. Among those with undiagnosed diabetes, 64 subjects (52%) had isolated post-load hyperglycaemia. Subjects with isolated post-load hyperglycaemia were older, more centrally obese and had higher blood pressure, HbA(1c), fasting plasma glucose, triglycerides, LDL cholesterol, high-sensitivity C-reactive protein and homeostasis model assessment of insulin resistance and lower homeostasis model assessment of ß-cell function than those without diabetes. The risk scores included age, gender, BMI, homeostasis model assessment, high-sensitivity C-reactive protein and HbA(1c). The full model had high sensitivity (84%) and specificity (87%) and area under the receiver operating characteristic curve (0.91), with a cut-off point of 23.81; validation in an independent data set showed 88% sensitivity, 77% specificity and an area under curve of 0.89. CONCLUSIONS: Over half of those with undiagnosed diabetes had isolated post-load hyperglycaemia. Homeostasis model assessment and high-sensitivity C-reactive protein are useful to identify subjects with isolated post-load hyperglycaemia, with improved performance over fasting plasma glucose or HbA(1c) alone.

[A Meta-analysis on association between statins and colorectal cancer].

Objective: To explore the association between statins and colorectal cancer and provide evidence for the prevention of colorectal cancer. Methods: Literatures about statins and colorectal cancer published from January 2000 to January 2020 were retrieved from CNKI, Wanfang data, PubMed and Cochrane Library database. The literatures which met the inclusion criteria were collected, and the Newcastle-Ottawa Scale and Jadad score were used to assess the studies. Meta-analysis was performed with statistical software Revman 5.0 and Stata 12.1. Results: A total of 31 studies, involving more than 1.62 million subjects, were included in the analysis. The case-control study (RR=0.93, 95%CI: 0.88-0.98), the cohort study (RR=0.75, 95%CI: 0.63-0.88) and the randomized controlled trial (RR=0.79, 95%CI: 0.65-0.97) showed moderate protective effect of statins. Using statin <5 years (RR=0.86, 95%CI: 0.76-0.96), average daily dosage ≥34 mg (RR=0.81, 95%CI: 0.66-0.98) and lipid-soluble statins (RR=0.86, 95%CI: 0.74-0.99) also had preventive effect on colorectal cancer; while lovastatin (RR=1.07, 95%CI: 1.00-1.14) increased the risk of colorectal cancer. Conclusion: Statins have protective effect on colorectal cancer.

Reversal of weightlessness-induced musculoskeletal losses with androgens: quantification by MRI.

Microgravity causes rapid decrement in musculoskeletal mass is associated with a marked decrease in circulatory testosterone levels, as we reported in hindlimb-suspended (HLS) rats. In this model which simulates microgravity, we hypothesized that testosterone supplementation should prevent these losses, and we tested this in two studies. Muscle volumes and bone masses were quantitated by using magnetic resonance imaging (MRI) on day 12. In the first study, 12-wk-old Sprague-Dawley rats that were HLS for 12 days lost 28.5% of muscle volume (53.3 +/- 4.8 vs. 74.5 +/- 3.6 cm3 in the ground control rats; P < 0.001) and had a 5% decrease in bone mineral density (BMD) (P < 0.05). In the second study, 30 male 12-wk-old Wistar rats were HLS and were administered either a vehicle (control), testosterone, or nandrolone decanoate (ND). An additional 20 rats were used as ground controls, one-half of which received testosterone. HLS rats had a significant reduction in muscle volume (42.9 +/- 3.0 vs. 56 +/- 1.8 cm3 in ground control rats; P < 0.01). Both testosterone and ND treatments prevented this muscle loss (51.5 +/- 2 and 51.6 +/- 1.2 cm3, respectively; a 63% improvement; P < 0. 05). There were no statistical differences between the two active treatment groups nor with the ground controls. Similarly, there was an 85% improvement in BMD in the testosterone group (1.15 +/- 0.04 vs. 1.04 +/- 0.04 density units in vehicle controls; P < 0.05) and a 76% improvement in the ND group (1.13 +/- 0.07 density units), whereas ground control rats had a BMD of 1.17 +/- 0.03 density units. Because serum testosterone levels are markedly reduced in this model of simulated microgravity, androgen replacement seems to be a rational countermeasure to prevent microgravity-induced musculoskeletal losses.

Bipolar implant shoulder arthroplasty.

A bipolar implant was designed by the author in 1975 for reconstruction of the severely arthritic shoulder. It has the advantage of not requiring glenoidal component fixation, but still provides an artificial joint interface. The ball of the humeral intramedullary stemmed component articulates with a polyethylene bearing within the glenoid cup component. This bipolar prosthesis was implanted in 15 shoulders of patients who presented severe arthritic shoulder disabilities. The follow up period averaged 41 months. Nine patients had rheumatoid arthritis, and five had osteoarthritis; all presented with severe pain and joint crepitation with loss of motion. A "shoulder score" system, based on the rating of pain, activities of daily living and range of motion, was devised to categorize the results obtained. Patients obtained greatly improved range of motion with good to excellent pain relief and very good functional restoration. Radiographically, the implant was well tolerated and there was no stem loosening. This procedure appears to be safe and efficacious for use in the severely arthritic shoulder.

Reconstruction of the thumb.

Based on 25 years of experience (1960-1984) with 188 cases, six approaches to thumb reconstruction are categorized as follows: pollicization using the index finger; pollicization using a finger stump; free transplant of a toe to reconstruct the thumb; reconstruction of the thumb by bone grafting and free flap transfer from the great toe with the nail; reconstruction of the thumb by turning up the skin over the dorsum of the stump and lengthening with bone grafting, and reconstruction of the thumb with bone grafting and tubular skin grafting. A well-reconstructed thumb should be in proper position with good stability, have good sensation, be of proper length, and have a satisfactory aesthetic appearance. Proper selection of patients, based on the level of thumb loss, condition of other fingers, and age, occupation, and activities of the patient, is a key to successful reconstruction of the thumb. Care must be taken to avoid excessive interference with the original function of the donor site.

Replantation of severed limbs--clinical analysis of 91 cases.

From 1964 to 1980, 91 replantations of severed limbs were performed at Peking Ji Shui Tan Hospital, The People's Republic of China. Seventy of these replantations were successful, and 21 were failures, for a success rate of 77%. The highest success rate was in replantations at the wrist level, with the lowest success rate occurring for replantations at the proximal forearm. In clean-cut injuries, successful reattachment was achieved in 88%. Injuries resulting in twisting and tearing trauma inflicted by a revolving machine rendered the poorest outcome. No significant difference existed between the viability rates of replantations of complete or nearly complete severance. Causes of injury and failed replantations varied.

Inhibition of glutathione synthesis with propargylglycine enhances N-acetylmethionine protection and methylation in bromobenzene-treated Syrian hamsters.

The finding that liver necrosis caused by the environmental glutathione (GSH)-depleting chemical, bromobenzene (BB) is associated with marked impairment in O- and S-methylation of BB metabolites in Syrian hamsters raises questions concerning the role of methyl deficiency in BB toxicity. N-Acetylmethionine (NAM) has proven to be an effective antidote against BB toxicity when given after liver GSH has been depleted extensively. The mechanism of protection by NAM may occur via a replacement of methyl donor and/or via an increase of GSH synthesis. If replacement of the methyl donor is an important process, then blocking the resynthesis of GSH in the methyl-repleted hamsters should not decrease NAM protection. This hypothesis was examined in this study. Propargylglycine (PPG), an irreversible inhibitor of cystathionase, was used to inhibit the utilization of NAM for GSH resynthesis. Two groups of hamsters were pretreated with an intraperitoneal (ip) dose of PPG (30 mg/kg) or saline 24 h before BB administration (800 mg/kg, ip). At 5 h after BB treatment, an ip dose of NAM (1200 mg/kg) was given. Light microscopic examinations of liver sections obtained 24 h after BB treatment indicated that NAM provided better protection (P < 0.05) in the PPG + BB + NAM group than in the BB + NAM group. Liver GSH content, however, was lower in the PPG + BB + NAM group than in the BB + NAM group. The Syrian hamster has a limited capability to N-deacetylated NAM. The substitution of NAM with methionine (Met; 450 mg/kg) resulted in a higher level of GSH in the BB + Met group than in the BB + NAM group (P < 0.05). The enhanced protection by PPG in the PPG + BB + NAM group was accompanied by higher (P < 0.05) urinary excretions of specificO- and S-methylated bromothiocatechols than in the BB + NAM group. The results suggest that NAM protection occurs primarily via a replacement of the methyl donor and that methyl deficiency occurring in response to GSH repletion plays a potential role in BB toxicity.

High tension electrical burns of upper arms treated by segmental excision of necrosed humerus. An introduction of a new surgical method.

This paper describes treating high-tension electrical burns of the upper arms by segmental excision of the necrosed humerus. This is a new surgical method of treating local electrical burns. The authors use modification of traditional surgical method, shorten the course of treatment, and preserve the injured limb. However, this surgical method should not be used to treat all high-tension electrical burns of the upper arm, and should be used only under certain conditions. Therefore, it is important to grasp the operative indications.