[Clinical effects of flaps or myocutaneous flaps transplantation after titanium mesh-retaining debridement in repairing the wounds with exposed titanium mesh after cranioplasty]

Objective: To explore the clinical effects of flaps or myocutaneous flaps transplantation after debridement to repair the wounds with exposed titanium mesh after cranioplasty on the premise of retaining the titanium mesh. Methods: This study was a retrospective observational study. From February 2017 to October 2022, 22 patients with titanium mesh exposure after cranioplasty who met the inclusion criteria were admitted to the Department of Plastic, Aesthetic & Maxillofacial Surgery of the First Affiliated Hospital of Xi'an Jiaotong University, including 15 males and 7 females, aged from 19 to 68 years. After admission, treatments such as bacterial culture of wound exudate sample, anti-infection, and dressing change were carried out. Thorough surgical debridement was performed when the wound improved, and the wound area was 3.0 cm×2.0 cm to 11.0 cm×8.0 cm after debridement. The wound was repaired with local flaps, expanded flaps, or free latissimus dorsi myocutaneous flaps according to the size, location, severity of infection, and surrounding tissue condition of the wounds, and the areas of flaps or myocutaneous flaps were 5.5 cm×4.0 cm to 18.0 cm×15.0 cm. The donor areas of flaps were sutured directly or repaired by split-thickness skin grafts from head. The wound repair method was recorded. The survivals of flaps or myocutaneous flaps after surgery and wound healing in 2 weeks after surgery were recorded. During postoperative follow-up, recurrence of infection or titanium mesh exposure in the implanted area of titanium mesh was observed; the head shapes of patients, scar formation of the operative incision, and baldness were observed. At the last follow-up, the satisfaction of patients with the treatment effect (dividing into three levels: satisfied, basically satisfied, and dissatisfied) was evaluated. The total treatment costs of patients during their hospitalization were calculated. Results: The wounds in 11 cases were repaired with local flaps, the wounds in 5 cases were repaired with expanded flaps, and the wounds in 6 cases were repaired with free latissimus dorsi myocutaneous flaps. All flaps or myocutaneous flaps survived completely after surgery, and all wounds healed well in 2 weeks after surgery. Follow up for 6 to 48 months after operation, only one patient with local flap grafting experienced a recurrence of infection in the titanium mesh implanted area at more than one month after surgery, and the titanium mesh was removed because of ineffective treatment. Except for one patient who had a local depression in the head after removing the titanium mesh, the rest of the patients had a full head shape. Except for myocutaneous flap grafting areas in 6 cases and skin grafting area in 1 case with local flaps grafting had no hair growth, the other patients had no baldness. All the scars in surgical incision were concealed. At the last follow-up, 19 cases were satisfied with the treatment effects, 2 cases were basically satisfied, and 1 case was dissatisfied. The total treatment cost for patients in this group during hospitalization was 11 764-36 452 (22 304±6 955) yuan. Conclusions: For patients with titanium mesh exposure after cranioplasty, on the premise of adequate preoperative preparation and thorough debridement, the wound can be repaired with appropriate flaps or myocutaneous flaps according to the wound condition. The surgery can preserve all or part of the titanium mesh. The postoperative wound healing is good and the recurrence of infection or titanium mesh exposure in the titanium mesh implanted area is reduced, leading to good head shape, reduced surgical frequency, and decreased treatment costs.

[CD44 regulates biological behavior and Ras signaling pathway in nasopharyngeal carcinoma stem cells]

Objective: To study the biological behavior of nasopharyngeal carcinoma stem cells and to explore the activation of Ras signaling pathway regulated by CD44. Methods: CNE2-SC and 5-8F-SC were nasopharyngeal carcinoma stem cells and obtained by serum-free suspension culture. Cell counting kit-8 (CCK-8) assay, colony formation assay, Transwell migration assay, cell adhesion array were used to investigate the growth, proliferation, migration and adhesion of nasopharyngeal carcinoma stem cells. Western blot test was used to detect the expressions of Ras signaling pathway related proteins and siRNA-mediated interference was used to determine the activation of Ras signaling pathway regulated by CD44. Results: The growth rates of CNE2-SC and 5-8F-SC cells were significantly lower than those of nasopharyngeal carcinoma cells at 24, 48 and 72 hours after inoculation (P<0.05). After 14 days of implantation, the colony formation rates of CNE2-SC (44.5±1.9)% and 5-8F-SC (47.4±1.8)% were higher than those of CNE2 (34.9±1.5)% and 5-8F (37.2±1.7)%, respectively(P<0.01). The migration cell number of CNE2-SC was (87.6±7.8), 3.97 times higher than that of CNE2 (P<0.01). The migration cell number of 5-8F-SC was (67.2±5.7), 3.07 times higher than 5-8F (P<0.01). The adhesion rates of CNE2-SC and CNE2 cells were (42.1±7.6)% and (8.9±2.0)%, respectively at 3 hours after inoculation and were (82.4±5.0)% and (12.1±2.2)% at 6 hours after inoculation, respectively. The adhesion rate of CNE2-SC cells was higher than that of CNE2 cells (all P<0.01). The adhesion rates of 5-8F-SC and 5-8F cells were (53.6±6.1)% and (7.3±1.5)% at 3 hours after inoculation, and (90.7±3.6)% and (11.0±1.2)% at 6 hours after inoculation, respectively. The adhesion rate of 5-8F-SC cells was higher than that of 5-8F cells (P<0.01). The expression levels of CD44, Ras and N-cadherin were significantly higher, while phosphatase and tensin homolog deleted on chromosome 10 (PTEN), E-cadherin in nasopharyngeal carcinoma stem cells were lower than those of the nasopharyngeal carcinoma cells. Furthermore, the levels of phosphorylated mitogen extracellular kinase1/2 (p-MEK1/2) and phosphorylated extracellular signal-regulated protein kinase1/2 (p-ERK1/2)were significantly increased in nasopharyngeal carcinoma stem cells (P<0.01). Correlation analysis showed that the protein expression levels of CD44 was highly positively correlated with RAS in nasopharyngeal carcinoma stem cells(r=0.985, P=0.002; r=0.962, P=0.038). Deletion of CD44 in CNE2-SC decreased the expression levels of HER-2, Ras and p-ERK1/2, p-Akt and phosphorylated protein kinase C-δ(p-PKCδ) (P<0.01). Conclusions: Despite compare to the nasopharyngeal carcinoma cell, nasopharyngeal carcinoma stem cells grows at a relatively slow rate, the capacities of clone formation, migration, adhesion are promoted. This may be related to the CD44-regulated abnormal activation of Ras signaling pathway.

Comparative efficacy and safety of lock solutions for the prevention of catheter-related complications including infectious and bleeding events in adult haemodialysis patients: a systematic review and network meta-analysis

BACKGROUND

Central venous catheters are used extensively as temporary or permanent vascular access for haemodialysis patients. Catheter-related bloodstream infections are the main complication of central venous catheters and increase morbidity and mortality in haemodialysis patients.

OBJECTIVES

The aim was to assess the most appropriate lock solution for central venous catheters to prevent catheter-related bloodstream infections and other complications.

DATA SOURCES

Medline, Embase and the Cochrane Central Register of Controlled Trials from the date of their inception to August 2018 were used as data sources. The reference lists of eligible studies and relevant reviews were also checked.

STUDY ELIGIBILITY CRITERIA AND PARTICIPANTS

Randomized controlled trials (RCTs) comparing different lock solutions for the prevention of central venous catheter-related infectious and bleeding complications for adult dialysis patients were included.

INTERVENTIONS

Interventions were lock solutions for haemodialysis catheters.

METHODS

The primary outcomes were catheter-related bloodstream infections and bleeding events. The secondary outcomes were catheter malfunction, exit-site infection, and all-cause mortality. We estimated summary risk ratios (RRs) using pairwise and network meta-analysis. We assessed the risk of bias of individual studies with the Cochrane risk of bias tool.

RESULTS

Forty-nine trials (7020 patients) were included for this study. Compared with heparin 5000 U/mL, antibiotic locks (antibiotics with trisodium citrate (TSC), ethylenediamine tetraacetic acid (EDTA), heparin 5000 U/mL, low-dose heparin or urokinase) and ethanol locks were more effective in preventing catheter-related bloodstream infections. Antimicrobial agents plus low-dose heparin (500-2500 U/mL), TSC and low-dose heparin locks had lower risk of bleeding events than heparin 5000 U/mL. None of the lock solutions reduced rates of catheter malfunction and all-cause mortality compared with heparin 5000 U/mL. In summary, antibiotics plus low-dose heparin was ranked as the best lock solution. The overall results were not materially changed in sensitivity analyses.

CONCLUSIONS

Taking into account both efficacy and safety, antibiotics plus low-dose heparin (500-2500 U/mL) may be the preferred lock solution.

[Survey on the quadrivalent influenza vaccine intention and related factors of health care workers in the Pearl River Delta region from 2015 to 2017]

Objective: To analyze the quadrivalent influenza vaccine intention of 718 health care workers (HCWs) in the Pearl River Delta region from 2015 to 2017. Method: In May 2018, 718 HCWs from the department related to the diagnosis and treatment of influenza in 17 hospitals (6 tertiary hospitals, 5 secondary hospitals and 6 primary hospitals) from Guangzhou, Jiangmen, Zhuhai and Dongguan were selected by using stratified sampling method. Questionnaire survey and face-to-face interview were used to collect the information of influenza vaccination, the intention of the quadrivalent influenza vaccine, the acceptance of free and required vaccination policies, and recommendations for increasing influenza vaccination intentions from 2015 to 2017. The multivariate logistic regression was used to analyze factors associated with the vaccination intention. Results: A total of 718 HCWs were surveyed and 147 of them were interviewed face to face. Among them, the vaccination rate of primary hospitals [17.39%(40/230)] was higher than that of other hospitals (χ(2)=15.80, P<0.05). If the vaccine could be free, 84.82% (609/718) of HCWs would like to be vaccinated. The multivariate logistic regression showed that the factors, HCWs who were aged ≥50 years (OR=3.44, 95%CI:1.43-8.28), worked in department of prevention and health care (OR=2.35, 95%CI:1.16-4.75), learned about the quadrivalent influenza vaccine (OR=2.94, 95%CI:2.08-4.18), knowed that HCWs are priority (OR=2.33, 95%CI:1.56-3.48), and had a history of trivalent influenza vaccination from 2015 to 2017 (OR=4.70, 95%CI:3.08-7.15), were associated with the vaccination intention. Conclusion: HCWs in the Pearl River Delta region had weak inclination of getting quadrivalent influenza vaccine. HCWs who were age (≥50 years old), worked in department of prevention and health care, learned about the quadrivalent influenza vaccine, knowed that HCWs are priority, and had a history of trivalent influenza vaccination from 2015 to 2017 were factors positively associated with the vaccination intention.

Nutritional effects on the mycelial growth and enzymatic activity of Isaria farinosa, and Hepialus larvae growth

AIMS

To investigate the nutritional requirements of the mycelial growth and pathogenesis-related enzymatic activity on Isaria farinosa and the nutritional effect of fungus on its host Hepialus larvae.

METHODS AND RESULTS

Sixteen carbon sources, 16 nitrogen sources and 9 vitamin combinations were tested. The nutritional conditions that significantly prevented I. farinosa pathogenesis were selected as feed additives for rearing Hepialus larvae. Citric acid significantly inhibited the growth of I. farinosa and the activity of three enzymes. l-histidine and l-aspartic acid significantly reduced the dry weights of mycelia and their protease and lipase activities. Vitamin combination that lacked VB 1 significantly increased the growth of I. farinosa and enhanced its chitinase and lipase activities. l-aspartic acid, VB 1 or a combination of them were beneficial for maintaining the larvae survival rate and decreasing the disease rate. The result provides new insight to develop a nutrition-based strategy to control fungal epidemics during insect rearing.

CONCLUSIONS

The ability of some specific nutrients to inhibit mycelial growth and enzymatic activity can prevent epidemics of fungal disease.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results will aid in the development of nutrition-based strategies to control entomopathogenic fungal epidemics during the large-scale rearing of insects.

Lack of an association between the XRCC1 Arg399Gln polymorphism and gastric cancer based on a meta-analysis

Association between the XRCC1 Arg399Gln polymorphism and susceptibility to gastric cancer has been investigated; overall, the results have been inconclusive. We made a meta-analysis of 13 case-control studies, including 3278 cases and 6243 controls. Crude odds ratios (OR) with 95% confidence intervals (95%CI) were used to assess this possible association. We found no evidence of a significant association between the XRCC1 Arg399Gln polymorphism and gastric cancer risk (in the additive inheritance model, OR = 0.986, 95%CI = 0.831-1.156, in the dominant inheritance model, OR = 1.044, 95%CI = 0.890-1.224 and in the recessive inheritance model, OR = 0.975, 95%CI = 0.894-1.063). We conclude that the XRCC1 Arg399Gln polymorphism is not a risk factor for developing gastric cancer.

Downregulated NM23-H1 expression is associated with intracranial invasion of nasopharyngeal carcinoma

Because the focus of nasopharyngeal carcinoma (NPC) is very close to intracranial organs, it often makes incursions into cranial cavity. Identification of intracranial invasion-associated indicators will provide potential therapeutic targets for NPC patients with intracranial invasion. In this regard, Human Xpro™ HC-plus cancer-related gene chip was utilised to screen intracranial invasion-associated genes for NPC from the biopsied primary focus tissue samples. In all, 8 upregulated and 23 downregulated genes were obtained. VEGF165 and MMP-9, the two upregulated genes, and NM23-H1, the downregulated one, were further confirmed by immunohistochemistry, quantitative real-time PCR and western blot. Invasion-associated cellular and nude mouse models were subsequently employed to study the biological properties of NM23-H1. NM23-H1 expression was significantly lower in 5-8F cells compared with that in 6-10B cells. Moreover, patch-clamp and transwell chamber were adopted to investigate the invading potential-associated biological dynamic mechanisms in the two cell lines, and Ca²⁺ current and motility were significantly elevated in 5-8F cells compared with that in 6-10B cells. Berberine, an inhibitor of Ca²⁺ current, could substantially increase the expression of NM23-H1 and decrease 5-8F cell motility. The specificity of berberine on NM23-H1 and cell motility was confirmed by RNAi assay.

Effect of complex amino acid imbalance on growth of tumor in tumor-bearing rats

AIM: To investigate the effect of complex amino acid imbalance on the growth of tumor in tumor-bearing (TB) rats.

METHODS: Sprague-Dawlley (SD) rats underwent jejunostomy for nutritional support. A suspension of Walker-256 carcinosarcoma cells was subcutaneously inoculated. TB rats were randomly divided into groups A, B, C and D according to the formula of amino acids in enteral nutritional solutions, respectively. TB rats received jejunal feedings supplemented with balanced amino acids (group A), methionine-depleted amino acids (group B), valine-depleted amino acids (group C) and methionine- and valine-depleted complex amino acid imbalance (group D) for 10 days. Tumor volume, inhibitory rates of tumor, cell cycle and life span of TB rats were investigated.

RESULTS: The G₀/G₁ ratio of tumor cells in group D (80.5 ± 9.0)% was higher than that in groups A, B and C which was 67.0% ± 5.1%, 78.9% ± 8.5%, 69.2% ± 6.2%, respectively (P < 0.05). The ratio of S/G₂M and PI in group D were lower than those in groups A, B and C. The inhibitory rate of tumor in groups B, C and D was 37.2%, 33.3% and 43.9%, respectively (P < 0.05). The life span of TB rats in group D was significantly longer than that in groups B, C, and A.

CONCLUSION: Methionine/valine-depleted amino acid imbalance can inhibit tumor growth. Complex amino acids of methionine and valine depleted imbalance have stronger inhibitory effects on tumor growth.

Toxicities and therapeutic effect of 5-fluorouracil controlled release implant on tumor-bearing rats

AIM: To investigate the toxicities, biodistribution and anticancer effect of 5-fluorouracil controlled release implant (5-FUCI) on Walker 256 carcinosarcoma cells in Wistar rats.

METHODS: Experiment 1: Wistar rats were randomly divided into three groups (27 rats per group). Blank implant was implanted in left lobe of the liver, and rats were treated with saline solution (in group A) or 5-fluorouracil (subcutaneous injection, group B). 5-FUCI was inserted in left lobe of the liver (group C). The gastrointestinal and hematological toxicities were observed and contents of element F in group C were assayed. Experiment 2: on day 6 after Walker-256 carcinosarcoma transplantation in left lobe of the liver, 5-FUCI was implanted in right lobe of the liver (group E) or left lobe (group F), and rats in control group (group D) were inserted blank implant. Tumor inhibition rate and survival time were investigated.

RESULTS: 5-FUCI showed no obvious toxic effect, extraction of Evan’s blue from gastrointestinal tissue was normal, the peripheral white blood cells and bone marrow nucleated cells were not reduced, compared with control group (P > 0.05). Histological examination revealed that there were no visible changes in small intestinal mucosa, The concentration of 5-fluorouracil in left lobe of the liver was 9.84, 28, 34 times as much as those of right lobe of the liver, heart and kidney respectively after the implantation in group C. They kept a high level of fluorouracil in left lobe of the liver, ranging from (4.414% ± 0.482%) to (7.800% ± 0.804%), for eight weeks. Survival days were 28.0 ± 2.2, 30.0 ± 3.2 and 38.7 ± 6.7 d in group D, E and F, respectively.

CONCLUSION: 5-FUCI shows no obvious toxicities to gastrointestinal tract and myelotoxicity. After implantation, it kept a high level of 5- fluorouracil in surrounding tissues of the implant for eight weeks. Its antitumor effect on Walker-256 carcinosarcoma is demonstrated.

Relationship between nuclear morphometry, DNA content and resectability of pancreatic cancer

AIM: To investigate the association of nuclear morphometry and DNA content with resectability of pancreatic cancer.

METHODS: A total of 36 patients with pancreatic adenocarcinoma were divided into resectable group and unresectable group. The nuclear morphometry and DNA contents of tumor cells were analyzed by IBAS autoimagine analyzer from paraffin-embedded materials. Localization size, histological type and grade, and clinical stage of the tumor were evaluated. Factors influencing resectability of pancreatic cancer were investigated using stepwise regression analysis.

RESULTS: Statistical significance was found in nuclear DNA content (integrated optical density, IOD) of tumor cells (1.64 ± 0.41 vs 2.96 ± 0.55), DNA ploidy, ages (46.5 ± 5.3 years vs 58.6 ± 0.7 years) and tumor volumes (298.1 ± 101.5 cm³vs 634.7 ± 512.5 cm³) in both groups (P < 0.05), and no difference was found in the nuclear morphometry (P > 0.05). The rates of diploid/tetraploid and aneuploid were 66.7% and 33.3% in resectable group respectively, and 38.9% and 62.1% in unresectable group, respectively (P < 0.05). IOD (X₁₂), ploidy status (X₁₃) and clinical stage (X₃) were radical resectable indicators with statistical significance. The regression equation for resectability was Y = -9.2053 + 3.5428X₁₂ + 2.5390X₁₃ - 2.3001X₃ (RR = 0.8780, P < 0.01).

CONCLUSION: There is a high correlation between resectability of pancreatic cancers and their DNA contents, DNA ploidy status and clinical stage.

Influence of methionine/valine-depleted enteral nutrition on nucleic acid and protein metabolism in tumor-bearing rats

AIM: To investigate the effects of methionine/valine-depleted enteral nutrition (EN) on RNA, DNA and protein metabolism in tumor-bearing (TB) rats.

METHODS: Sprague-Dawlley (SD) rats underwent jejunostomy for nutritional support. A suspension of Walker-256 carcinosarcoma cells was subcutaneously inoculated. 48 TB rats were randomly divided in 4 groups: A, B, C and D. The TB rats had respectively received jejunal feedings supplemented with balanced amino acids, methionine-depleted, balanced amino acids and valine-depleted for 6 d before injection of 740 KBq ³H- methionine/valine via jejunum. The ³H incorporation rate of the radioactivity into RNA, DNA and proteins in tumor tissues at 0.5, 1, 2, 4 h postinjection of tracers was assessed with liquid scintillation counter.

RESULTS: Incorporation of ³H into proteins in groups B and D was (0.500 ± 0.020)% to (3.670 ± 0.110)% and (0.708 ± 0.019)% to (3.813 ± 0.076)% respectively, lower than in groups A [(0.659 ± 0.055)% to (4.492 ± 0.108)%] and C [(0.805 ± 0.098)% to (4.180 ± 0.018)%]. Incorporation of ³H into RNA, DNA in group B was (0.237 ± 0.075)% and (0.231 ± 0.052)% respectively, lower than in group A (P < 0.01). There was no significant difference in uptake of ³H by RNA and DNA between group C and D (P > 0.05).

CONCLUSION: Protein synthesis was inhibited by methionine/valine starvation in TB rats and nucleic acid synthesis was reduced after methionine depletion, thus resulting in suppression of tumor growth.

Submicrostructure and typing of female genital condylomata

Thirty biopsies from female genital condylomata were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to study structural characteristics and typing of condylomata. It was found that cytoplasmic clearing was marked in acuminate condylomata, diffuse interstitial and epithelial proliferation in nodular condylomata (flat condylomata), and invagination of the lesions into the interstitial tissue or glandular ducts in endophytic condylomata. In nodular condylomata, SEM also showed some structural features similar to those of intra-epithelial neoplasia. Microridges on the surface of squamous cells had villiform of granular changes. On the surface of a percentage of squamous or columnar cells, there were holes with a diameter of about 3 to 5 microns. A number of giant cells were seen among other cells. The cervical squamatization zone contained groups of special cells covered with dense microvilli. TEM of nodular condylomata revealed some pictures resembling active proliferation of tumor cells, such as enlarged or irregular nuclei (large N/C ratio), evaginated or invaginated nuclear membranes, condensed chromatin attached to the inner part of the nuclear membrane, transparent nucleoplasm, and frequent nucleosomes and karyokinesis. Virus particles with the morphological characteristics of HPV (naked hexagon-like particles with an average diameter of 45-50 nm) were seen in some nuclei with markedly condensed chromatin. It is suggested that HPV-induced genital condylomata, especially nodular one (flat condylomata), entail a potential progression to malignancy.