[Correlation between serum growth differentiation factor 11 level and severity of coronary artery disease in patients with acute myocardial infarction].

Objective: To investigate the correlation between serum growth differentiation factor 11 (GDF11) level and coronary artery lesions in patients with ST-segment elevation myocardial infarction (STEMI), and the predictive efficacy of nomogram risk prediction model based on GDF11 combined with traditional risk factors on the occurrence of STEMI. Methods: This study was a retrospective cross-sectional study. Patients hospitalized in the Department of Cardiology of the 904th Hospital of Joint Logistic Support Force of People's Liberation Army of China from 2016 to 2018 were selected and divided into control group and STEMI group. The demographic data, blood lipid level, laboratory indicators of blood and GDF11 level were collected. Logistic regression analysis screened out independent correlated factors for the occurrence of STEMI. Spearman correlation analysis clarified the correlation of each indicator with the SYNTAX or Gensini scores. A nomogram risk prediction model for the risk of STEMI occurrence and the receiver operating characteristic curve was used to compare the prediction efficiency of each model. Results: A total of 367 patients were enrolled, divided into control group (n=172) and STEMI group (n=195), age (66.5±11.8), male 222 (60.49%). The serum GDF11 level of STEMI group was significantly lower than that of the control group (36.20 (16.60, 70.75) µg/L vs. 85.00 (53.93, 117.10) µg/L, P<0.001). The results of multivariate logistic regression analysis showed serum GDF11(OR=0.98, 95%CI: 0.97-0.99) and traditional independent risk factors such as smoking, diabetes, C-reactive protein, homocysteine, lipoprotein (a) and apolipoprotein A1/B were independent correlate factors for the occurrence of STEMI (P<0.05). Spearman correlation analysis showed that serum GDF11 was negatively correlated with SYNTAX score and Gensini score (P<0.05). The nomogram model constructed by serum GDF11 combined with traditional independent risk factors (AUC=0.85, 95%CI: 0.81-0.89) had better predictive value for the occurrence of STEMI than the traditional nomogram model constructed by independent risk factors(AUC=0.80, 95%CI:0.75-0.84) or serum GDF11 (AUC=0.76, 95%CI: 0.72-0.81), all P<0.01. Conclusions: Serum GDF11 is an independent correlate factor in the occurrence of STEMI and is negatively correlated with the severity of coronary artery lesions in patients with STEMI. The nomogram model constructed based on GDF11 combined with traditional risk factors can be a good predictor for the occurrence of STEMI.

[Determination of Methoxyacetic acid in urine by pre-column derivatization-liquid-liquid microextraction coupled with gas chromatography].

Objective: To establish a method for determining methoxyacetic acid in urine by pre-column derivatization-liquid-liquid microextraction coupled with gas chromatography (GC) . Methods: Phosphate buffer solution, tert-butoxyacetic acid (internal standard) and pentafluorobenzyl bromide (derivative) were added to the urine sample. After derived in a water bath at 90 ℃ for 40 min, the mixture was cooled and filtered, then the dichloromethane was used as an extractant. After being shaken and centrifuged, the lower organic phase was sucked and injected into a gas chromatograph, separated by a DB-5 capillary column, and detected by an ECD detector. Results: The linear range of the method was 0.6~60.0 mg/L with the correlation coefficients (r) above 0.999. The average recovery was76.6%~110.7%, the inter-day precision was 8.00%~8.82%, and the detection limit was 0.13 mg/L. Conclusion: The method was founded to be high sensitivity, low organic reagent usage and green. So it is suitable for the detection of methoxyacetic acid in urine of occupational exposure to ethylene glycol monomethyl ether.

[Determination of n-butyl alcohol in urine by headspace solid-phase microextraction coupled with gas chromatography].

Objective: To establish a headspace solid phase microextraction-gas chromatography method for determination of n-Butyl alcohol in urine. Methods: In October 2019, the n-butyl alcohol in urine was extracted with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) solid-phase microextraction head. The conditions of salt amount, extraction temperature, extraction time and desorption time were optimized. The separation was performed on HP-5 (30 m×0.32 mm×0.25 µm) capillary column and detected with flame ionization detector. The quantification was based on the external standard curve. Results: The linear relationship of n-butyl alcohol in urine was good in the range of 0.04-3.00 mg/L, the correlation coefficient was 0.999, the detection limit of the method was 0.04 mg/L, the recovery was 77.4%-102.8%, the intra-run precision was 3.67%-8.11%, and the inter-assay precision was 4.94%-6.90%. Conclusion: The method has simple operation, high concentration efficiency and high sensitivity, and it is suitable for the determination of n-butyl alcohol in urine of occupational exposure to n-butyl alcohol.

[Determination of metabolites of styrene in urine by dispersive liquid-liquid microextraction coupled with high performance liquid chromatography].

Objective: To establish a method for the determination of mandelic acid and phenylglyoxylic acid in the urine of styrene by dispersive liquid-liquid microextraction-high coupled with high performance liquid chromatography. Methods: N-octanol was used as an extractant and ethanol was used as a dispersing agent. The phenylglycolic acid and phenylglyoxylic acid in the urine were extracted, and the upper liquid was taken after vortexing and centrifuged, and then was injected into HPLC for analysis. Results: The linear correlation coefficient of the concentration of phenylglycolic acid in the range of 0~10.0 mg/L was greater than 0.999. The detection limit of the method was 9.9 µg/L, the recovery rates were 86.1%~101.6%. The intraday RSDs of the method were 1.07%~3.76%, and the interday RSDs were 1.24%~3.33%. The linear correlation coefficient of phenylglyoxylic acid in the range of 0.0~2.0 mg/L is greater than 0.999. The detection limit of the method was 2.6 µg/L, the recovery rates were 88.8%~100.3%. The intraday RSDs of the method were 1.02%~ 3.17%, and the interday RSDs were 1.59%~2.41%. Conclusion: The method has low detection limit, high enrichment ratio and good sensitivity, and is suitable for determination of phenylglycolic acid and phenylglyoxylic acid in urine of occupational exposure to styrene.

[Determination of 1-methoxy-2-propanol in urine by headspace solid-phase microextraction coupled with gas chromatography].

Objective: To establish a method for the determination of 1-methoxy-2-propanol in urine using headspace solid phase micro-extraction coupled with gas chromatography. Methods: The 1-methoxy-2-propanol was enriched by headspace solid phase micro-extraction fiber coated with carbene/polydimethylsiloxane (CAR/PDMS) . Single factor rotation method was used to optimize the conditions of extraction temperature, salt amount, and extraction time. The separation was performed on DB-5 (30 m×0.32 mm×0.25 µm) capillary column and detected with flame ionization detector. The quantification was based on the standard curve. Results: The concentration of 1-methoxy-2-propanol in urine was linear in the range of 0.50-10.0 mg/L, and the linear correlation coefficient was 0.9993. The detection limit of the method was 0.14 mg/L, and the limit of quantification was 0.45 mg/L. The recovery was 85.8% to 104.7%, and the RSD of intra- and inter-batch precision were 3.25%-6.65% and 0.81%-3.96%, respectively. Conclusion: The method is high sensitivity and simple operation, and is suitable for the determination of 1-methoxy-2-propanol in urine of occupational exposure population.

Nanofibers promote HepG2 aggregate formation and cellular function.

Formation of hepatocyte spheroids is a necessary strategy for increasing liver-specific function in vitro. In this study, HepG2 cells showed good viability when grown on a polylactic acid-chitosan (PLA-CS) nanofiber and aggregated to form multicellular spheroids on the PLA-CS nanofibers with a diameter of approximately 100-200 mm in 5 days of culture, whereas no such aggregation was observed in cells cultured on 24-well plates. Hepatocyte spheroids formed on the PLA-CS nanofibers displayed excellent hepatic-related protein expression, such as albumin and urea, compared to HepG2 cells cultured on the 24-well plates. These results indicated that formation of the hepatocyte spheroids in nanofibers can increase and maintain hepatocyte functions for a longer time, supporting a new strategy for bioartificial liver development.

Familial multiple-organ arterial ectasia with massive hemoptysis.

Numerous large, thin-walled ectatic arteries up to 1 cm in diameter were encountered during operation on a 20-year-old patient. These vessels covered most of the right pleural surface. Similar symptomatic ectatic vessels were found arising from the left side and intracranially. Eight years later large arteriovenous malformations developed from chest wall and scar tissues that required ligations to control hemoptysis. This case was unique in that extensive multiorgan capillary and arterial systems were involved.

Use of OncoScint scan to assess resectability of hepatic metastases from colorectal cancer.

Patients with limited hepatic metastases from colorectal cancer can potentially be cured by resection. A number of patients deemed resectable by standard imaging procedures are found to have extrahepatic disease at laparotomy and are thus unresectable. A test capable of identifying these patients would assist in better patient selection. OncoScint (Cytogen Corp, Princeton, NJ) scan targets colorectal cancer by interacting with a tumor-associated glycoprotein. Can OncoScint scan be used to reliably identify patients with extrahepatic disease preoperatively? Between February 1996 and August 1998 eight patients with colorectal metastases to the liver were enrolled prospectively. All patients received preoperative OncoScint scan (indium-111) and underwent laparotomy. The laparotomy findings were correlated with the results of OncoScint scan. In four of eight patients (50%) OncoScint scan showed no extrahepatic disease. This was confirmed at laparotomy. All of these patients underwent hepatic resection. One of eight patients (12.5%) had OncoScint findings suggestive of extrahepatic disease pathologically confirmed during laparotomy. Three of eight patients (37.5%) had OncoScint findings of extrahepatic disease not confirmed by laparotomy. All three patients underwent hepatic resection. One of the three patients is still disease free for more than 48 months after hepatic resection. If OncoScint scan had been used to determine resectability this patient with false positive scan would have been denied a potentially curative operation. Because of the unacceptably high false positive rate the study was terminated after eight patients. Because of its high false positive rate (37.5%) OncoScint scan is not a reliable test for the assessment of extrahepatic disease. Other tests need to be developed to accurately stage extrahepatic disease with an acceptably low false positive rate to prevent exclusion of patients who can potentially be cured.

Deep venous thrombosis with pulmonary embolus after selective embolization of an internal iliac artery aneurysm.

A 69-year-old man with an isolated right internal iliac artery aneurysm measuring 5.6 cm in diameter was treated with percutaneous embolization inducing thrombosis of the aneurysm. Four months later, he was seen with thrombosis of the right common iliac vein and pulmonary embolus. He subsequently underwent ligation of the aneurysm and repair of the right common iliac artery. Computed tomographic and operative findings suggested that the iliac vein thrombosis was the result of direct compression by the aneurysm itself, as well as perianeurysmal inflammation that encased the right common iliac vein. This report summarizes this case and presents a new potential long-term complication after successful selective embolization of an internal iliac artery aneurysm.

A comparative study of saphenous vein, internal jugular vein, and knitted Dacron patches for carotid artery endarterectomy.

To determine whether the choice of material used for patch closure following carotid artery endarterectomy (CAE) affected the immediate operative results, the early follow-up results, or the incidence of early restenosis, a retrospective study of 275 consecutive carotid endarterectomies by two vascular surgeons was performed. Among 275 primary CAEs performed between July 1991 and August 1993, 159 (57.8%) were closed with saphenous vein (SV), 25 (9.1%) with double-thickness internal jugular vein (JV), and 91 (33.1%) with knitted Dacron (KD). Primary closure was not used in any of the arteries in this series. The overall perioperative mortality rate was 1.1% and the rate of major and minor morbidity was 4.4% There were four (1.5%) perioperative strokes: two (1.3%) in the SV group, one (4.0%) in the JV group, and one (1.1%) in the KD group. Two-hundred fifty-eight (93.8%) of the 275 endarterectomies were followed postoperatively for 2 to 35 months (mean 14.4). Two-hundred nineteen (79.6%) were evaluated using duplex scans during follow-up with a mean interval of 13.7 months. Of the arteries studied, four (3.6%) in the SV group, none in the JV group, and six (8.4%) in the KD group demonstrated restenosis of > 50% at the time of follow-up (NS). In addition, one (0.9%) artery in the SV group, one (5.6%) in the JV group, and none in the KD group demonstrated complete occlusion. Retrospective analysis of the data showed no statistically significant differences in perioperative morbidity, mortality, or early postoperative restenosis whether the artery was closed with saphenous vein, jugular vein, or knitted Dacron patches. Longer follow-up is needed to determine whether rates of late restenosis and aneurysmal dilation will differ between synthetic and autologous patches.

Immediate and long-term results of carotid endarterectomy for asymptomatic high-grade stenosis.

We examined the operative risks and long-term results of carotid endarterectomy for asymptomatic patients in terms of stroke, death, and recurrent stenosis. The results of a nonrandomized study with a follow-up of 1 to 104 months (mean 46 months) is reported. A tertiary referral center served as the setting for this report. One hundred consecutive patients with severe but asymptomatic carotid artery stenosis out of a total of 514 patients undergoing carotid endarterectomy were entered into this study. The severity of carotid disease was determined by duplex scanning and confirmed arteriographically. No patients were lost to follow-up after surgery. Eighty-nine operations (77%) were done under cervical block anesthesia and all arteries were closed with saphenous vein patches. Life-table analysis showed that the stroke-free rate at 5 years was 96.3% with an ipsilateral stroke-free rate of 98.2%. The 5-year overall survival rate was 78.2% with a stroke-free survival rate of 75%. Carotid endarterectomy can be performed safely for asymptomatic patients believed to be at risk for stroke. The potential for early death due to myocardial disease, late stroke, and recurrent stenosis do not justify advising patients against undergoing prophylactic carotid endarterectomy for asymptomatic high-grade stenosis.