Meta-analysis of the effectiveness and safety of robotic-assisted versus laparoscopic transabdominal preperitoneal repair for inguinal hernia

BACKGROUND

Inguinal hernia is a common global disease. This study aims to investigate the effectiveness and safety of robot-assisted transabdominal preperitoneal repair (RTAPP) and laparoscopic transabdominal preperitoneal repair (LTAPP) for inguinal hernia.

METHODS

We conducted a thorough search in Cochrane Library, Embase, and PubMed for relevant clinical studies. After applying inclusion and exclusion criteria, the quality of selected studies was assessed using the Jadad scale for randomized controlled studies and the Newcastle-Ottawa scale for observational studies. Meta-analysis was performed using RevMan 5.3 software.

RESULTS

A total of ten studies were included, comprising two randomized controlled studies and eight non-randomized controlled studies. Meta-analysis results revealed no statistically significant differences between the RTAPP group and the LTAPP group regarding hospital stay [MD = 0.21 days, 95% CI (-0.09, 0.51), P = 0.17], incidence of seroma [OR = 0.85, 95% CI(0.45, 1.59), P = 0.61], overall complication rate [OR = 1.22, 95% CI(0.68, 2.18), P = 0.51], readmission rate [OR = 1.31, 95% CI(0.23, 7.47), P = 0.76], and recurrence rate [OR = 0.82, 95% CI(0.22, 3.07), P = 0.77]. However, the RTAPP group had longer operation time compared to the LTAPP group [MD = 14.02 minutes, 95% CI (6.65, 21.39), P = 0.0002], and the cost of the RTAPP procedure was higher than that of the LTAPP procedure [MD = $4.17 thousand, 95% CI (2.59, 5.76), P<0.00001].

CONCLUSION

RTAPP for inguinal hernia is a safe and feasible approach, however, it is associated with increased operation time and treatment costs.

Effectiveness and safety of different doses of febuxostat compared with allopurinol in the treatment of hyperuricemia: a meta-analysis of randomized controlled trials

BACKGROUND

The prevalence of hyperuricemia has increased steadily with the continuous improvement of living standards. Some studies have reported the clinical effectiveness and safety of different doses of febuxostat in comparison with allopurinol in hyperuricemia treatment, but the sample sizes of the studies have been small, and the results have been inconsistent. We designed this meta-analysis to evaluate the effectiveness and safety of different doses of febuxostat compared with allopurinol in the treatment of hyperuricemia.

METHODS

The Cochrane Library, Embase, PubMed, Web of Science and ClinicalTrials.gov databases were searched to identify randomized controlled trials (RCTs) comparing the use of febuxostat and allopurinol for the treatment of hyperuricemia. The effectiveness and safety of different doses of febuxostat and allopurinol in treating hyperuricemia were assessed using meta-analysis.

RESULTS

A total of 11 randomized controlled trials were included in the meta-analysis. The results of the meta-analysis showed that the percentage of patients achieving serum uric acid levels of 6.0 mg/dL or less was higher among patients taking febuxostat (80 mg/d) than among patients taking allopurinol (200-300 mg/d) [RR = 1.79, 95% CI (1.55, 2.08), P < 0.00001]. However, there was no statistically significant difference in the percentage of patients achieving serum uric acid levels of 6.0 mg/dL or less between febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 1.10, 95% CI (0.93, 1.31), P = 0.25]. There was also no statistically significant difference in the incidence of gout between the febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 0.97, 95% CI (0.64, 1.49), P = 0.91] or between the febuxostat (80 mg/d) and allopurinol (200-300 mg/d) [RR = 1.13, 95% CI (0.81, 1.58), P = 0.48].No significant difference in the incidence of major adverse reactions as observed between the febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 1.16; 95% CI (0.43, 3.16), P = 0.77] or between the febuxostat (80 mg/d) and allopurinol (200-300 mg/d) [RR = 1.06; 95% CI (0.79, 1.42), P = 0.70]. The incidence of adverse cardiovascular events did not differ significantly between the febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 1.30; 95% CI (0.57, 2.95), P = 0.53] or between the febuxostat (80 mg/d) and allopurinol (200-300 mg/d) [RR = 1.79; 95% CI (0.74, 4.32), P = 0.20].

CONCLUSIONS

Febuxostat (80 mg/d) was associated with a higher percentage of patients achieving serum uric acid levels of 6.0 mg/dL or less than allopurinol (200-300 mg/d), however, febuxostat (80 mg/d) did not exhibit better efficacy in reducing the incidence of gout. More attention should be devoted to the adverse reactions caused by an increase in febuxostat doses.

Safety of unfixed mesh in laparoscopic total extraperitoneal inguinal hernia repair: A meta-analysis of randomized controlled trials

Background

Whether the effect of the unfixed mesh during laparoscopic total extraperitoneal (TEP) inguinal hernia repair can lead to hernia recurrence remains controversial.

Methods

The PubMed, Cochrane Library, and EMBASE databases were searched to retrieve clinical randomized controlled trials (RCTs) comparing nonfixation of mesh and fixation of mesh in TEP inguinal hernia repair, and we performed a metaanalysis with RevMan 5.3 software.

Results

Fifteen RCTs were included in the metaanalysis, which showed that the operation time (P = 0.001) of the unfixed mesh group was shorter than that of the fixed mesh group; additionally, the postoperative 24-h pain score (P = 0.04) and incidence of urinary retention (P = 0.001) were lower in the unfixed mesh group. There was no significant difference between the unfixed mesh group and the fixed mesh group in terms of hospital stay (P = 0.47), time to resume normal activities (P = 0.51), incidence of haematoma (P = 0.96), incidence of chronic pain (P = 0.20), and recurrence rate (P = 0.09).

Conclusion

Unfixed mesh in TEP inguinal hernia repair shows no elevated recurrence rates compared to fixed mesh and is clinically safe.

Meta‑analysis of single-incision laparoscopic versus multi-trocar laparoscopic totally extraperitoneal inguinal hernia repair

Whether single-incision laparoscopic totally extraperitoneal (SIL-TEP) inguinal hernia repair is similar or superior to multi-trocar laparoscopic totally extraperitoneal (MTL-TEP) inguinal hernia repair is controversial. We conducted this meta-analysis to compare the safety, efficacy and cosmetic effect of the two surgical methods. We systematically searched the Cochrane Library, Embase database and PubMed database for published studies on SIL-TEP and MTL-TEP inguinal hernia repair. The studies were screened and evaluated for quality according to the inclusion and exclusion criteria, and RevMan 5.3 software was used for meta-analysis. Twenty studies were included, including 7 randomized controlled studies and 13 nonrandomized controlled studies. Meta-analysis revealed no significant difference between SIL-TEP and MTL-TEP inguinal hernia repair in terms of unilateral operation time (P = 0.12), bilateral operation time (P = 0.72), pain score on the first day after operation (P = 0.61], chronic pain rate (P = 0.61), total complication rate (P = 0.26), hospital stay (P = 0.72), and recurrence rate (P = 0.83), but the cosmetic effect score (P = 0.002) was higher in the former. These findings demonstrate that SIL-TEP inguinal hernia repair is safe, reliable and feasible. In addition, it can result in a better cosmetic effect of the incision than MTL-TEP inguinal hernia repair. SIL-TEP inguinal hernia repair should be considered for patients with stricter cosmetic requirements.Clinical trial registration: INPLASY2022110085.

Efficacy and safety of ilioinguinal neurectomy in open tension-free inguinal hernia repair: A meta-analysis of randomized controlled trials

BACKGROUND

There is still controversy surrounding routine ilioinguinal neurectomy in open tension-free inguinal hernia repair.

METHOD

PubMed, Cochrane Library and EMBASE databases were searched for randomized controlled trials of ilioinguinal neurectomy in open tension-free inguinal hernia repair. Revman 5.3 software was used for meta-analysis.

RESULT

Meta-analysis revealed that the incidence of severe pain on the first postoperative day was lower in the ilioinguinal neurectomy group (ING) than in the ilioinguinal nerve preservation group (INPG) [P < 0.0001]. The incidence of no pain in the first month postoperatively [P = 0.0004], the incidence of no pain in the sixth months postoperatively [P < 0.00001], and the numbness incidence in the first month postoperatively [P = 0.001] in the ING was higher than that in the INPG. There was no significant difference in the incidence of severe pain in the first month postoperatively [P = 0.20], the numbness incidence in the sixth postoperative month [P = 0.05], the hypoesthesia incidence in the first [P = 0.15] and sixth [P = 0.85] postoperative months between the two groups.

CONCLUSION

Ilioinguinal neurectomy in open tension-free inguinal hernia repair can better prevent postoperative pain.

Efficacy and safety of glue mesh fixation for laparoscopic inguinal hernia: A meta-analysis of randomized controlled trials

It is still controversial whether glue can be used for mesh fixation in laparoscopic inguinal hernia repair. The aim of this meta-analysis was used to systematically evaluate the effectiveness and safety of glue mesh fixation in laparoscopic tension-free inguinal hernia repair. The PubMed database, EMBASE database and Cochrane Library were searched to collect published randomized controlled trials (RCTs) on laparoscopic tension-free inguinal hernia repair with glue mesh fixation. Sixteen RCTs and 2409 patients with inguinal hernia were included. The meta-analysis showed that compared with the mechanical mesh fixation group(MMFG), the glue mesh fixation group(GMFG) had significantly reduced incidences of chronic pain[relative risk (RR) = 0.40, 95% confidence interval (CI) (0.28,0.57), P < 0.00001], urinary retention[RR = 0.53, 95% CI(0.29,0.97), P = 0.04], haematoma[RR = 0.23, 95% CI(0.09,0.58), P = 0.002] and total complications[RR = 0.28, 95% CI(0.18,0.44), P < 0.00001]; there were no significant differences in pain score on postoperative day 1[MD = -1.33, 95% CI(-2.93,0.26), P = 0.10], operation time[MD = 1.46, 95% CI(-3.97,6.88), P = 0.60] and recurrence rate[RR = 0.72, 95% CI(0.35,1.47), P = 0.37] between the two groups. In conclusion, the application of glue mesh fixation in laparoscopic inguinal hernia repair is safe and reliable with fewer complications. Moreover, it can reduce the incidence of chronic pain without increasing the recurrence rate. However, due to the small number of cases in this analysis and limitations in the quality of the included studies, the findings need to be further verified by multicentre, large-sample and high-quality RCTs in the future.

The role of prophylactic antibiotics in elective inguinal tension-free hernia repair: A systematic review and meta-analysis

Whether to use antibiotics to prevent surgical site infection in elective inguinal tension-free hernia repair has been controversial. To systematically evaluate the effect of prophylactic antibiotic application in elective inguinal tension-free hernia repair, we identified all published randomised controlled trials of the effect of prophylactic antibiotic application on elective inguinal tension-free hernia repair were collected by computer retrieval from the China National Knowledge Infrastructure; VIP Database; Wanfang Database; China Biomedical Literature Database; and PubMed, EMBASE and Cochrane Library databases. Meta-analysis was performed by RevMan 5.3 software. The meta-analysis showed that the total incidence of surgical site infections [P = 0.003] and the incidence of superficial surgical site infections [P = 0.004] in the antibiotic group (AG) were lower than those in the non-antibiotic group (NAG). There was no significant difference in the total incidence of postoperative infections [P = 0.06], deep surgical site infections [P = 0.26] and seroma [P = 0.52] between the AG and the NAG. Based on current evidence, the application of prophylactic antibiotics in elective inguinal tension-free hernia repair can prevent the total incidence of surgical site infections and that of superficial surgical site infections but cannot prevent the total incidence of postoperative infection events, incidence of deep surgical site infections and incidence of seroma.

Efficacy and Safety of Preoperative Radiotherapy Versus Chemoradiotherapy in Advanced Rectal Cancer: A Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This meta-analysis was conducted to evaluate the safety and efficacy of preoperative radiotherapy (RT) combined with surgery and preoperative chemoradiotherapy (CRT) combined with surgery for locally advanced rectal cancer.

METHODS

PubMed, EMBASE and Cochrane Library were searched to collect published randomized controlled trials of preoperative radiotherapy or preoperative CRT combined with surgery for the treatment of locally advanced rectal cancer. Studies were screened according to inclusion and exclusion criteria, and quality was evaluated; RevMan 5.3 software was used for meta-analysis.

RESULTS

In total, 7 related studies involving 3100 patients with locally advanced rectal cancer were evaluated. The pathological complete response rate, negative lymph node rate, R0 resection rate, and incidence of grade III/IV adverse reactions were lower in the RT group than in the CRT group. In the absence of postoperative chemotherapy, the 5-year local recurrence rate of RT was higher than that of CRT, but there was no significant difference between the groups among those who underwent postoperative chemotherapy. Moreover, there was no significant difference between the groups with regard to the 5-year survival rate, anal-preserving rate, or incidence of anastomotic leakage.

CONCLUSION

Preoperative CRT is better than preoperative RT for the treatment of advanced rectal cancer, though the adverse reaction rate is higher.

Meta-analysis on the effect of combining Lianhua Qingwen with Western medicine to treat coronavirus disease 2019

BACKGROUND

Coronavirus disease 2019 (COVID-19) has become a worldwide life-threatening pandemic. Lianhua Qingwen is believed to possess the ability to treat or significantly improve the symptoms of COVID-19. These claims make it important to systematically evaluate the effects of using Lianhua Qingwen with Western medicine to treat COVID-19.

OBJECTIVE

To evaluate the safety and efficacy of combination therapy, employing Lianhua Qingwen with Western medicine, to treat COVID-19, using a meta-analysis approach.

SEARCH STRATEGY

China National Knowledge Infrastructure, Wanfang Database, VIP Database, PubMed, Embase, and Cochrane Library databases were searched for studies evaluating the effect of Lianhua Qingwen-Western medicine combination therapy in the treatment of COVID-19.

INCLUSION CRITERIA

(1) Research object: hospitalized patients meeting the diagnostic criteria of COVID-19 were included. (2) Intervention measures: patients in the treatment group received Lianhua Qingwen treatment combined with Western medicine, while the control group received either Western medicine or Chinese medicine treatment. (3) Research type: randomized controlled trials and retrospective study were included.

DATA EXTRACTION AND ANALYSIS

Two researchers extracted the first author, the proportion of males and females, age, body temperature, course of treatment, rate of disappearance of main symptoms, duration of fever, adverse reactions, and total effectiveness from the literature. Odds ratio (OR) and 95% confidence interval (CI) were used as the effect value for count data, and mean difference (MD) and 95% CI were used as the effect value for measurement data.

RESULTS

Six articles met the inclusion criteria, including a total of 856 COVID-19 patients. The meta-analysis showed that Lianhua Qingwen combination therapy achieved higher rates of fever reduction (OR = 3.43, 95% CI [1.78, 6.59], P = 0.0002), cough reduction (OR = 3.39, 95% CI [1.85, 6.23], P < 0.0001), recovery from shortness of breath (OR = 10.62, 95% CI [3.71, 30.40], P < 0.0001) and recovery from fatigue (OR = 2.82, 95% CI [1.44, 5.53], P = 0.003), higher total effectiveness rate (OR = 2.51, 95% CI [1.73, 3.64], P < 0.00001), and shorter time to recovery from fever (MD = -1.00, 95% CI [-1.04, 0.96], P < 0.00001), and did not increase the adverse reaction rate (OR = 0.65, 95% CI [0.42, 1.01], P = 0.06), compared to the single medication control.

CONCLUSION

The Lianhua Qingwen and Western medicine combination therapy is highly effective for COVID-19 patients and has good clinical safety. As only a small number of studies and patients were included in this review, more high-quality, multicenter, large-sample-size, randomized, double-blind, controlled trials are still needed for verification.

Meta-analysis of arbidol versus lopinavir/ritonavir in the treatment of coronavirus disease 2019

Objectives

To systematically evaluate the efficacy and safety of arbidol and lopinavir/ritonavir (LPV/r) in the treatment of coronavirus disease 2019 (COVID‐19) using a meta‐analysis method.

Methods

The China Knowledge Network, VIP database, WanFang database PubMed database, Embase database, and Cochrane Library were searched for a collection of comparative studies on arbidol and lopinavir/ritonavir in the treatment of COVID‐19. Meta‐analysis was used to evaluate the efficacy and safety of Arbidol and lopinavir/ritonavir in the treatment of COVID‐19.

Results

The results of the systematic review indicated that Arbidol had a higher positive‐to‐negative conversion rate of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) nucleic acid on Day 7 (p = 0.03), a higher positive‐to‐negative conversion rate of SARS‐CoV‐2 nucleic acid on Day 14 (p = 0.006), a higher improvement rate of chest computed tomography on Day 14 (p = 0.02), a lower incidence of adverse reactions (p = 0.002) and lower rate of mortality (p = 0.007). There was no difference in the rate of cough disappearance on Day 14 (p = 0.24) or the rate of severe/critical illness (p = 0.07) between the two groups.

Conclusions

Arbidol may be superior to lopinavir/ritonavir in the treatment of COVID‐19. However, due to the small number of included studies and the number of patients, high‐quality multicenter large‐sample randomized double‐blind controlled trials are still needed for verification.

[Analysis of M2 macrophage infiltration and its clinical significance in 44 patients with multiple primary cancers of the head and neck]

Objective: To investigate and analyze the characteristics of M2 macrophage infiltration and the clinical significance in patients with multiple primary cancers (MPCs) of head and neck in order to explore its role in the diagnosis and prognosis for patients with MPCs. Methods: RNA-seq data were downloaded from the Genomic Data Commons data portal (TCGA) and the R software v4.0.3 was used to statistically analyze the differences. A retrospective analysis was conducted by screening the clinical data of 44 patients (17 males and 27 females) with MPCs in head and neck from July 1998 to February 2016 in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. Clinical data from a batch of 41 patients (28 males and 13 females) with gingival cancer and without MPCs from August 2013 to December 2015 were collected and analyzed. The number of CD163 positive cells and the expression patterns in immunohistochemically panoramic slices were observed under high magnification. Chi-square test and Spearman correlation analysis were used to compare the difference and correlation between the CD163 positive counts and/or depths of invasion and the number of incidences. The descriptive statistics on the clinical features was performed by SPSS 25.0. Results: TCGA database analysis showed that the infiltration of macrophage in patients with squamous cell carcinoma of head and neck (HNSCC) was increased compared to the para-cancer sites. A total of 142 tissue samples from 44 patients with MPCs were selected in the present single-center retrospective research. The number of CD163-positive cells in MPCs patients [90.9% (40/44)] was significantly increased compared to single gingival cancer patients [61.0%(25/41)] (r=0.353, P=0.001), which was related to the number of occurrence (r=0.368, P=0.001). The ratio of the CD163 counts in primary tumor to the depths of invasion was positively correlated with the number of onsets (r=0.331, P=0.03). In terms of clinical features, the 44 patients with MPCs were mainly female, non-smoking, no alcohol addiction, no systemic history, Tis-T2 stage and N0 stage squamous cell carcinoma. The number of incidences ranged from two to eight. The incidence of cancer relative to synchronous cancer increased with the increased occurrence of MPCs. The primary cancer mainly occurred in tongue, gingiva and buccal sites, while the proportion of onset sites in gingiva, buccal and palate areas increased with the increased occurrence. Conclusions: M2 type macrophage counts and/or ratio to depth of infiltration were associated with the occurrence of MPCs, which could be used as a clinical indicator to distinguish single and MPCs in HNSCC. For early stage of HNSCC, patients with clinical characters of women, non-smoking, no alcohol addiction, no systemic medical history and sites of tongue, gingiva, and buccal should be paid more attention on their follow-up plan. The findings in the present study was also helpful to explore new treatment methods for the patients with MPCs.

Meta-analysis of mesh-plug repair and Lichtenstein repair in the treatment of primary inguinal hernia

The present study systematically evaluated the clinical effects of mesh-plug and Lichtenstein herniorrhaphy in the treatment of primary inguinal hernia. PubMed, Embase, and the Cochrane Library (cut-off: May 25, 2020) databases were searched to select randomized controlled trials (RCTs) on mesh-plug and Lichtenstein herniorrhaphy for the treatment of primary inguinal hernia. Articles that met the inclusion criteria were screened and evaluated for quality. RevMan 5.3 software was used to perform a meta-analysis of operation time, discomfort in the inguinal region, haematoma, seroma, infection, time to return to normal activities, incidence of postoperative chronic pain, and recurrence rate. Eleven RCTs with 1457 patients in the mesh-plug group and 1472 in the Lichtenstein group were included. Meta-analysis showed that the mesh-plug herniorrhaphy group had a shorter operation time than the Lichtenstein herniorrhaphy group [P < 0.0001] but a longer time to return to normal activities after surgery [MD = 1.48, 95% CI (0.58, 2.38), P = 0.001]. There were no significant differences in postoperative discomfort in the inguinal region [P = 0.90], seroma [P = 0.10], haematoma [P = 0.27], infection [P = 0.40], incidence of postoperative chronic pain [P = 0.90], or recurrence rate [P = 0.77] between groups. Mesh-plug herniorrhaphy requires a shorter operation time than Lichtenstein herniorrhaphy, and there is no significant difference in postoperative complications or recurrence rate between the two methods. Clinical trial registration: INPLASY202070088. Meta-analysis of mesh -plug repair and Lichtenstein repair in the treatment of primary inguinal hernia.

Meta-Analysis on the Efficacy and Safety of Laparoscopic Surgery for Large Gastric Gastrointestinal Stromal Tumors

BACKGROUND

The aim of this study was to conduct a meta-analysis comparing the safety and feasibility of laparoscopic versus open resection for gastric gastrointestinal stromal tumors (GISTs) larger than 5 cm.

METHOD

We searched the Cochrane Library, PubMed, and Embase for relevant articles. Randomized and nonrandomized clinical trials were identified and included in this study. Searching for related articles on large GIST (>5 cm) for laparoscopic resection (laparoscopic group [LAPG]) and open resection (open group [OG]), RevMan 5.3 was used for data analysis, comparing 2 groups of operation time, intraoperative blood loss, complications, length of hospital stay, recurrence rate, disease-free survival, and overall survival.

RESULTS

Seven studies including 440 patients were identified for the meta-analysis. Meta-analysis revealed that LAPG had less bleeding, shorter postoperative hospital stay, and a better 5-year disease-free survival. There was no significant difference between LAPG and OG in operation time, postoperative complications, recurrence rate, and overall survival.

CONCLUSION

Laparoscopic resection of large (>5 cm) GIST is safe and feasible and has the advantages of less intraoperative blood loss and fast postoperative recovery, with a good outcome in the recent oncology.

Effects of posthatch feed deprivation on residual yolk absorption, macronutrients synthesis, and organ development in broiler chicks

The aim of the research was to evaluate the dynamic changes of early posthatch starvation on residual yolk absorption, synthesis of macronutrients (protein, lipid, and glycogen), and organ development in broiler chicks. A total of 720 1-day-old chicks (Lingnan Yellow) were randomly assigned to 3 treatments: group A (nonfasted), group B (fasting for 24 h after placement), and group C (fasting for 48 h after placement). The trial lasted for 168 h, and water was provided ad libitum all the time. Sampling was performed at 0, 24, 48, 72, 120, and 168 h. Nonfasting (group A) promoted (P < 0.05) the absorption of amino acids, fatty acids, mineral elements, protein, and maternal antibody in the residual yolk of broiler chicks. The concentration of insulin-like growth factor 1 in plasma and the liver was higher (P < 0.05) in group A. Nonfasting enhanced (P < 0.05) the synthesis of protein and glycogen in the breast muscle and liver; the relative weights of the liver, pancreas, and spleen; and body weight, but retarded (P < 0.05) the synthesis of triglyceride in the liver. The results indicated that nonfasting (group A) after placement promoted the absorption of residual yolk and synthesis of protein and glycogen in the breast muscle and liver, whereas early feed deprivation promoted the synthesis of lipid in the liver. Thereby, nonfasting after placement promoted organ development and body growth of broiler chicks.

[Focus on application of dermabrasion in the treatment of deep partial-thickness burn wound at early stage]

There are several advantages in using dermabrasion to treat burn wound of deep-partial thickness at early stage, including accurate positioning, little damage to normal tissue, partial-damaged tissue preservation, easy to operate, no limited by burn wound location and area, fast wound healing, short hospital-stay, less hospitalization cost, slight scarring, wide indications, etc. It is of important clinical value for the treatment of deep partial-thickness burn wound at early stage.

[Delayed diagnosis of oral squamous cell neoplasms at different sites]

OBJECTIVE

To investigate the diagnostic delay of patients with oral squamous cell carcinoma by self-designed questionnaire to find out the significant influencing factors, so as to identify the influencing factors of the patient's delay and the risk of oral cancer.

METHODS

A total of 514 patients with primary oral squamous cell carcinoma were enrolled at Peking University School and Hospital of Stomatology from January 2014 to April 2016, including 334 men and 180 women, with a male to female ratio of 1.85:1. The youngest participant was 21 years old, with a maximum of 89 years and a median age of 57.6 years. The position of the disease according to International Classification of Diseases-10 (ICD-10) was divided into lip, buccal, gingival, retromolar, palate, floor of the mouth, tongue, and oropharynx. The age group is divided into 10 years. The level of education was divided into illiteracy, primary education level and advanced education level. Body mass index (BMI) was divided into three levels by 18 kg/m² and 25 kg/m². Visual analog scale (VAS) method was to evaluate the patient's preoperative pain. At the same time, the patients were examined by detailed questionnaire to understand the delay factors and delay characteristics, and use SPSS 18.0 software, analysis of variance and chi-square test to explore correlation.

RESULTS

Among all patients, the proportion of patients developed in the tongue was the highest (43.3%). Delay was defined by a span of three months or longer from the onset of symptoms until treatment. The delays to diagnosis according to location were as follows (in months and in descending order): lip (6.1 months), buccal (4.1 months), floor of the mouth (3.9 months), tongue (3.6 months), oropharyngeal (2.9 months), retromolar (2.7 months), palatine (2.4 months), and gingival (2.4 months). Different sites and delayed diagnosis were statistically significant (P=0.048). There were no statistically significant differences in gender, education, pain, smoking, drinking and VAS score.

CONCLUSION

The study has found that tumor positions and delay have a significant correlation. The position of the tumor is an obvious factor associated with the findings. The lip is the most likely to delay the diagnosis of oral positions. For the lip of the lesion, more than three months' obvious mass is recommended for timely treatment, while at admission, physicians should take the appropriate diagnostic method as soon as possible.

[Retrospect on 60 years' history and prospect of Department of Burns and Plastic Surgery of Provincial Hospital Affiliated to Shandong University]

The Department of Burns and Plastic Surgery of Provincial Hospital Affiliated to Shandong University is the leading team in Shandong province. It is integrated with clinical treatment, scientific research, teaching, personnel training, and medical service for social crisis, which undertakes the tasks of giving lessons and offering chances for noviciate and internship of burns and plastic surgery in College of Medicine of Shandong University. It is not only the training unit affiliated to College of Medicine of Shandong University for master students and doctoral students major in burns and plastic surgery, but also the national training base for specialists of burns and plastic surgery. It is the national key clinical subject of burn surgery. Over the past 60 years, with the concerted efforts of several generations, it has made significant contributions to the development and innovation of burns and plastic surgery in Shandong province and the whole China.

[Influence of gender, age and season on thyroid hormone reference interval]

Objective: Using clinical "big data" , to investigate the factors that affect the levels of thyroid hormones, and to explore the partitioning criteria for reference intervals (RI) of these hormones. Methods: An observation study was conducted. Information of 107 107 individuals undergoing routine physical examination in Peking Union Medical College Hospital from September 1(st,) 2013 to August 31(st,) 2016 was collected, thyroid hormone of these subjects were detected. To explore the test results distribution and differences of TSH, FT4 and FT3 by gender and age; according to the seasonal division standard of China Meteorological Administration, the study period was divided into four seasons, and the seasonal fluctuation on TSH was analyzed.To define the appropriate partition by gender, age and season according to significant difference analysis. Results: In male and female, the distributions of TSH were 1.779(0.578-4.758), 2.023(0.420-5.343)mU/L, respectively, and the level of TSH in female was higher than in male (Z=-37.600, P<0.001). The distributions of FT4 were 0.127(0.098-0.162), 0.117(0.091-0.151) μg/L, the distributions of FT3 were 3.33(2.47-3.74), 3.01(2.35-3.57)ng/L. And the level of FT4, FT3 in female were significantly lower than in male (Z=-94.000, -154.600, all P<0.001). Furthermore, males were divided into two groups by 65 years old and female were divided by 50 years old, respectively, and the distributions of TSH in male and female of older group were 1.818(0.528-5.240), 2.111(0.348-5.735)mU/L, in younger group were 1.778(0.582-4.696), 1.991(0.427-5.316)mU/L. The level of TSH in older group was significantly higher than in younger group (Z=-2.269, -10.400, all P<0.05), and the distribution of TSH in older group was much wider than in younger. The distribution of whole in spring, summer and autumn was 1.869( 0.510-5.042)mU/L, in winter was 1.978(0.527-5.250) mU/L, and the difference between them had statistical significance (Z=-15.000, P<0.001). Conclusions: Gender and age significantly affect the serum levels of TSH, FT4, and FT3, the distribution of TSH in female and elder group are wider than in male, and that of FT4, FT3 are lower.Seasons significantly affect the serum TSH level, the peak value is observed in winter. There are obviously differences between "rough" RIs and manufacture recommended RIs. Each laboratory should establish reference intervals for thyroid hormones on the premise of appropriate grouping.

Serum Proteomics Analysis in Rats of Immunosuppression Induced by Chronic Stress

The immune system can be damaged by chronic stress. However, for this process, the involved molecular alterations and their regulatory roles played in immunosuppression still remain unclear. This study was aimed to identify the differences in serum protein expressions that are closely associated with the effect of chronic stress on immune function. Serum protein levels of rats in control group and chronic stress group were measured by iTRAQ analysis. Subsequently, among the 121 differentially expressed proteins screened between the two groups, 46 proteins were upregulated (>1.5-fold, P < 0.05), while 75 proteins were downregulated (<0.67-fold, P < 0.05). Bioinformatics analysis revealed that most of the differentially expressed proteins were in relation with the metabolic, cellular, response stimulus and immune system processes. The significantly differential expression of ceruloplasmin, haptoglobin, catalase and peroxiredoxin-1 were picked out for reconfirmation by ELISA analysis. The results were consistent with those obtained by iTRAQ. What is more, the roles of above-mentioned four proteins, apolipoprotein B-100 and heat-shock protein 90 in immunosuppression induced by chronic stress were discussed. Taken together, these findings may provide a new insight into better understanding the molecular mechanisms of immunosuppression induced by chronic stress.

[Experimental study of GeneXpert(®) system in the diagnosis of extra-pulmonary tuberculosis]

OBJECTIVE

To explore the application value of GeneXpert MTB/RIF for detection of extra-pulmonary tuberculosis and resistance to rifampin.

METHODS

A total of 150 samples were collected, including 33 needle aspirates from lymphoid tuberculosis, 23 needle aspirates from spinal tuberculosis, 49 from tuberculous pleural effusions, 24 from cerebrospinal fluid of tuberculous cephalomeningitis, and 21 urinary sediment samples from renal tuberculosis. Smear microscopy, mycobacterium tuberculosis culture and the MTB/RIF method were used to examine these samples and their positive rates were compared. Rifampin susceptibility tests was performed for culture-positive strains using proportion method, which was compared with the result from GeneXpert MTB/RIF method.

RESULTS

Of the 150 cases of extra-pulmonary tuberculosis, 17 samples were smear-positive, with a sensitivity of 11.3% (17/150); 30 were culture-positive with a sensitivity of 20.0% (30/150); and 96 were positive by MTB/RIF method with a sensitivity of 64.0% (96/150). There was a significant difference between MTB/RIF method and the culture method (χ(2)=59.61, P<0.01). The differences were also significant when the MTB/RIF method was compared with the smear method (χ(2)=88.60, P<0.01) or compared with culture plus smear methods (χ(2)=4.26, P<0.05). Separately, the differences were statistically significant between GeneXpert MTB/RIF method and other 2 methods for diagnosis of lymphoid tuberculosis (n=33, χ(2)=20.56, P<0.01 vs. culture method; χ(2)=27.13, P<0.01 vs. smear results) while no difference was found between culture and smear method (χ(2)=0.67, P>0.05), spinal tuberculosis (n=23, χ(2)=12.74, P<0.01 vs. culture method; χ(2)=14.81, P< 0.01 vs. smear method), tuberculous pleurisy (n=49, χ(2)=32.34, P<0.01 vs.culture method; χ(2)=49.69, P<0.01 vs. smear method) and renal tuberculosis (n=21, χ(2)=4.20, P<0.05 vs. culture method; χ(2) =8.40, P<0.01 vs. smear results). The sensitivity for tuberculous meningitis had no difference among these 3 methods (n=24, P>0.05). Rifampicin-resistance of the strains from the 30 culture-positive cases of extra-pulmonary tuberculosis (20.0%, 6/30) exhibited agreement with GeneXpert MTB/RIF test.

CONCLUSION

The simplicity and high sensitivity of GeneXpert MTB/RIF technology make it a good diagnostic test for rapid detection of extra-pulmonary tuberculosis and resistance to rifampin.

Prognostic factors in mandibular gingival squamous cell carcinoma: A 10-year retrospective study

The mandibular gingiva is the second most common site of oral cavity squamous cell carcinoma. This retrospective study was designed to determine the clinicopathological features of squamous cell carcinoma of the mandibular gingiva (MGSCC) and to establish a new risk model to predict overall survival. The study included 207 patients with primary MGSCC from January 2000 to September 2009. The medical charts were reviewed and data related to clinical characteristics, treatment provided, histopathological analysis, and follow-up were recorded. All patients underwent surgery as the first-line therapy; follow-up ranged from 1 to 171 months (median 63 months). Clinical characteristics and pathological outcomes were analyzed with respect to the 5-year overall survival rate. A survival risk model was established, and patients were classified into low-, moderate-, and high-risk groups based on the prognostic index designed in this study. The 5-year overall survival rates for the low-, moderate-, and high-risk groups were 92.3%, 76.9%, and 34.2%, respectively. Pathological node metastasis, perineural invasion, and extracapsular spread were the most significant predictive factors for 5-year overall survival. MGSCC is not aggressive, and the survival outcomes of MGSCC are better than those of squamous cell carcinoma (SCC) at other sites. It is suggested that patients with T2-T4 tumours undergo elective neck dissection and those with T1 tumours be followed up without addressing the neck.

[Inhibitory effect of imrecoxib combined with lobaplatin on tumor growth and lymph node metastasis of human lung cancer xenografts in nude mice]

OBJECTIVE

To evaluate the inhibitory effect of imrecoxib combined with lobaplatin on tumor growth and lymph node metastasis of human lung adenocarcinoma xenografts in nude mice, and to explore its possible mechanisms.

METHODS

Human lung cancer A549 cells were injected into Bal B/c nude mice subcutaneously. Twenty-eight healthy male nude mice were randomly divided into 4 groups: the control group, imrecoxib group, lobaplatin group and imrecoxib combined with lobaplatin group. Each group was treated with appropriate drugs and the tumor size was measured every five days. The expression of ezrin and E-cadherin protein was detected by immunohistochemistry and flow cytometry. Ezrin and E-cadherin mRNA were detected by real-time PCR.

RESULTS

The tumor inhibition rates of imrecoxib group, lobaplatin group and combination group were 36.7%, 54.6% and 69.2%, respectively. The tumor volumes of imrecoxib group [(905.33±113.31) mm(3)] and combination group [(507.74±77.50) mm(3)] were significantly lower than that of the control group (1355.33±189.04) mm(3) (P<0.05), and the tumor weights were significantly reduced [(1.13±0.14) g, (0.63±0.10) g respectively] vs. (1.69±0.24) g (P<0.05). The expressions of ezrin protein and mRNA in the imrecoxib group and combined treatment group were significantly lower than that of the control group (136.53±35.52, 74.72±19.48 vs. 175.62±21.16 for protein expression level; 0.54±0.03, 0.36±0.03 vs. 1.02±0.02 for mRNA expression level, respectively, P<0.05 for both), while the expression of E-cadherin protein and mRNA in the imrecoxib group and combined treatment group was significantly higher than that of the control group (253.78±38.87, 308.94±24.67 vs. 213.66±30.31 for protein expression level; 2.19±0.02, 3.02±0.02 vs. 1.05±0.03 for mRNA expression level, respectively, P<0.05 for both). There was a significant negative correlation between ezrin protein and E-cadherin protein (r=-0.737, P<0.01), as well as between ezrin mRNA and E-cadherin mRNA (r=-0.977, P<0.01).

CONCLUSIONS

Administration of imrecoxib combined with lobaphatin has inhibitory effects on the growth of non-small cell lung cancer xenografts and lymph node metastasis via down-regulated ezrin and upregulated E-cadherin. Imrecoxib and lobaplatin have a synergistic antitumor effect.

Effect of steam-flaked corn and soybeans on muscle and intramuscular fatty acid composition in Holstein calves

This study aimed to evaluate the effects of steam-flaked corn grains and soybeans on muscle fatty acid composition. Thirty Holstein bull calves (21 ± 3 d) were divided into 3 groups according to birth date and BW and were randomly assigned to receive fresh milk and a commercial pelleted starter diet containing extruded corn and soybean (ECS), steam-flaked corn and soybean (SFCS), or ground corn and raw soybean (GCS). The calves were fed the designated diet from 3 to 13 wk of age, after which they were slaughtered. The supraspinatus (CTM), longissimus lumborum (RLM), and spinalis dorsi (ERM) were analyzed to determine the chemical and intramuscular fatty acid composition. The fatty acid composition of muscle and its deposition differed among calves fed different starter feeds. Medium-chain fatty acid levels of the RLM and CTM were greater in GCS-fed calves than in ECS- and SFCS-fed calves ( < 0.05). Extruded processing increased the content of linoleic, linolenic, and arachidonic acids of the RLM ( < 0.05). The palmitoleic and -vaccenic acid content of the ERM were greater in GCS-fed calves than in ECS- or SFCS-fed calves ( < 0.05). No significant differences were observed among the 3 diets with respect to the stearic, oleic, linoleic, -9 -11 CLA, or arachidonic acid content of the ERM ( > 0.05). The levels of -3 and -6 fatty acids were similar among the 3 groups; a lower -6:-3 PUFA ratio was observed in GCS-fed calves ( < 0.05). The cereal processing method of the calf starter feed had no significant effect on the chemical composition of the CTM, RLM, or ERM. Therefore, different methods of processing corn and soybean in calf starter feeds had no effect on the chemical composition of the RLM, CTM, or ERM but had a significant effect on the intramuscular fatty acid composition.

Quantum phase transitions in interfacing two gapped systems of ordinary fermions driven by external strain and atomic adsorption

We study how the electronic structure of a single bilayer Bi on a single quintuple layer Bi2Se3 (Bi2Te3) changes with interface polarization, strain and H adsorption using first-principles calculations. We find that for strained systems the Dirac cone state does not show in the band gap. Coupled with strain and H adsorption, the six spin-polarized Dirac cones in the band gap are created by the interfacing two gapped films. The internal electrical field can result in variations in the work function relative to Bi and Bi2Se3 surfaces. Our findings confirm that the interface polarization, strain and atomic adsorption are the effective means to manipulate electronic structures and topological states on non-metallic surfaces, which could be helpful for realizing atomically thin spintronic devices.

Temporal lobe dysplasia: a characteristic sonographic finding in thanatophoric dysplasia

OBJECTIVE

To determine the incidence of temporal lobe dysplasia (TLD) detected on prenatal ultrasound in thanatophoric dysplasia (TD) over an 11-year period in a tertiary referral center.

METHODS

An 11-year retrospective review of perinatal autopsies from 2002 to 2013 was performed to identify cases of TD. The ultrasound images and corresponding reports of all TD cases were examined for the presence of TLD. The same set of images subsequently underwent a retrospective review by a perinatal radiologist with knowledge of the features of TLD to determine whether they could be identified.

RESULTS

Thirty-one cases of TD underwent perinatal autopsy, and prenatal ultrasound imaging was available for review in 24 (77%). Mean gestational age at diagnosis of TD was 21.3 (range, 18-36) weeks. TLD was identified and reported in 6/24 (25%) cases; all six cases occurred after 2007. Retrospective interpretation of the ultrasound images identified features of TLD in 10 additional cases. In total, 16/24 (67%) cases displayed sonographic evidence of TLD. Temporal trends showed that TLD features were present in 50% (5/10) of all TD cases between 2002 and 2006 and in 79% (11/14) of those detected between 2007 and 2013.

CONCLUSIONS

At present, the detection rate of TLD by ultrasound is low but may be increased by modified brain images that enhance visualization of the temporal lobes. Prenatal identification of TLD may help in the prenatal diagnosis of TD and thus provide more accurate prenatal counseling and guide molecular investigations to confirm the specific diagnosis of TD.

Beneficial effects of jejunal continuity and duodenal food passage after total gastrectomy: a retrospective study of 704 patients

AIM

To evaluate effects of reconstruction procedures on post-operative outcomes and nutritional status after total gastrectomy.

METHODS

The study group comprised 704 consecutive patients with gastric cancer who underwent total gastrectomy between December 1985 and December 2003. Six alimentary reconstruction procedures were performed, including jejunal continuity [Braun, modified Braun I and II and functional jejunal interposition (FJI)] and jejunum transection ["P" Roux-en-Y and "P" jejunal interposition (PJI)]. The duodenal food passage was maintained only by FJI and PJI. We evaluated the time interval to restore food intake after surgery and the incidence of complications and nutritional status for 12 months.

RESULTS

Patients who received jejunum transection required 7.8+/-2.5 days and 11.9+/-4.9 days to restore liquid and semi-liquid food intake, respectively, which reduced to 3.9+/-2.1 days for liquid and 7.9+/-3.9 days for semi-liquid food intake by jejunum continuity. The incidence rates of reflux esophagitis and Roux-en-Y syndrome in patients receiving jejunum transection were 23.5% and 42.4%, respectively, which were decreased to 9.35% and 14.7%, respectively, by jejunal continuity. Furthermore, prognostic nutrition index score of patients receiving the procedures maintaining duodenal food passage (52.9+/-10.9) was higher than that of patients without the duodenal food passage (46.7+/-8.2).

CONCLUSION

Jejunal continuity and duodenal food passage showed beneficial effects on clinical outcomes after surgery. Among these six procedures, FJI was the only procedure to combine the benefits of jejunal continuity and maintaining the duodenal food passage, indicating that FJI has potential clinical application to improve the quality of patient's life after total gastrectomy.

Factors Affecting Growth Factor Activity in Goat Milk

Growth factors that are present in goat milk may be responsible for its beneficial effects on the digestive system as described in ancient Chinese medical texts. To develop a nutraceutical product rich in growth factors for promoting gastrointestinal health, it is essential to collect milk with consistently high growth factor activity. Therefore, we investigated the factors affecting growth factor activity in goat milk. Among the 5 breeds of dairy goats tested, milk from Nubian goats had the highest growth factor activity. Tight-junction leakage induced by a 24-h milking interval did not increase growth factor activity in the milk. Milk collected from pregnant does had a significantly higher growth factor activity than milk collected postpartum. Growth factor activity decreased during the first 8 wk of lactation, fluctuated thereafter, and then increased dramatically after natural mating. During wk 1 to 8, growth factor activity was inversely correlated with milk yield and week of lactation. No correlation was observed during wk 9 to 29. After natural mating of the goats, the growth factor activity in the milk correlated significantly with somatic cell count and conductivity (a measure of membrane permeability), and correlated inversely with milk yield. Based on the above data, goat milk with higher growth factor activity could be selectively collected from Nubian pregnant does.

Structural genomics efforts at the Chinese Academy of Sciences and Peking University

Structural genomics efforts at the Chinese Academy of Sciences and Peking University are reported in this article. The major targets for the structural genomics project are targeted proteins expressed in human hematopoietic stem/progenitor cells, proteins related to blood diseases and other human proteins. Up to now 328 target genes have been constructed in expression vectors. Among them, more than 50% genes have been expressed in Escherichia coli, approximately 25% of the resulting proteins are soluble, and 35 proteins have been purified. Crystallization, data collection and structure determination are continuing. Experiences accumulated during this initial stage are useful for designing and applying high-throughput approaches in structural genomics.

Multivariate statistical study of heavy metal enrichment in sediments of the Pearl River Estuary

The concentrations and chemical partitioning of heavy metals in the sediment cores of the Pearl River Estuary were studied. Based on Pearson correlation coefficients and principal component analysis results, Al was selected as the concentration normalizer for Pb, while Fe was used as the normalizing element for Co, Cu, Ni and Zn. In each profile, sections with metal concentrations exceeding the upper 95% prediction interval of the linear regression model were regarded as metal enrichment layers. The heavy metal accumulation mainly occurred at sites in the western shallow water areas and east channel, which reflected the hydraulic conditions and influence from riparian anthropogenic activities. Heavy metals in the enrichment sections were evaluated by a sequential extraction method for possible chemical forms in sediments. Since the residual, Fe/Mn oxides and organic/sulfide fractions were dominant geochemical phases in the enriched sections, the bioavailability of heavy metals in sediments was generally low. The 206Pb/207Pb ratios in the metal-enriched sediment sections also revealed the influence of anthropogenic sources. The spatial distribution of cumulative heavy metals in the sediments suggested that the Zn and Cu mainly originated from point sources, while the Pb probably came from non-point sources in the estuary.

The mass transfer process and the growth rate of protein crystals

In this paper, protein crystal growth is studied by a Mach-Zehnder interferometer and an image process system. The interference fringe images are recorded during the crystallization of tetragonal hen egg white lysozyme crystal. Concentration distributions of the protein solution are given from the interference fringe images recorded by the Mach-Zehnder interferometer with a real time servo system of a four-step phase shift. The mass transfer flux and the crystal growth rates are obtained from the concentration distribution. The results show that the observed rates are in accordance with those demonstrated by measurements of the experimental images; therefore the method for determining growth rate by the diffusion process is reasonable.

Administration of chinese herbal medicines facilitates the locomotor activity in dystrophin-deficient mice

The purpose of this study was to access the effects of chinese herbal medicines on Duchenne muscular dystrophy (DMD). We use dystrophin-deficient mice (mdx), an animal model of DMD, to evaluate the effect of chinese herbal medicines on locomotor activity. The consumption of water for each mouse was controlled during the three-month experimental session. Each mouse was allowed to drink 3 ml water with or without herbal medicines daily for three months. The estimated intake of chinese herbal medicine in adult mdx mouse with 30 g weight is 100 mg/kg per day, close to a dose used in human. The locomotor activity of the mdx mice was measured every month. Monitoring the locomotor activity of mdx mice after three-month administration of chinese herbal medicines, the results showed that liu-wei-di-huang-wan (LDW) and san-lin-pai-tsu-san (SPS) can facilitate locomotor activity with the parameters of horizontal activity, total distance, number of movements, movement time, vertical activity, number of vertical movements, vertical movement time, stereotypy, number of stereotyped movements, and stereotyped movement time. These results suggest that either LDW or SPS can act as a potent herbal medicine for the pharmacological treatment of DMD patients.

Molecular scaffold of a new pokeweed antifungal peptide deduced by 1H nuclear magnetic resonance

The antifungal peptide from seeds of Phytolacca americana (Pokeweed), designated PAFP-S hereinafter, is a recently found cationic peptide which consists of 38 amino acid residues and exhibits a broad spectrum of antifungal activity, including inhibition of certain saprophytic fungi and some plant pathogens. The secondary structure and three cysteine pairings have been investigated by 1H NMR analysis. The results show that the molecular scaffold of PAFP-S features a triple-stranded antiparallel beta-sheet knotted by a typical disulfide bridge motif, which characterizes the knottin fold. CD spectroscopy indicates a high stability of the molecule in solution. Therefore, PAFP-S should be a new member of the knottin structural family and the first antifungal peptide that adopts the knottin-like fold.

Overexpression, purification, crystallization and preliminary X-ray diffraction analysis of Cu,Zn superoxide dismutase from Peking duck

The cDNA encoding Peking duck Cu,Zn superoxide dismutase (dSOD) was cloned and sequenced. The recombinant enzyme was overexpressed in Escherichia coli, purified to homogeneity and crystallized using the sitting-drop vapour-diffusion technique. Trigonal crystals of dSOD were obtained at 278 K at low ionic strength and around neutral pH. These crystals belong to space group P3(2)21, with unit-cell parameters a = 124.4, c = 163.5 A, gamma = 120 degrees. The asymmetric unit contains four dimers (eight monomers of Cu,Zn dSOD) and has a 56% solvent content, with a V(M) of 2.8 A(3) Da(-1). On a Rigaku R-AXIS IIc image-plate area-detector system, the crystal diffracted to 2.9 A. Unusual supermolecular double-helix packing with 9(2)2 non-crystallographic symmetry in crystals has been observed in the initial structural analysis.

Solution structure of PAFP-S: a new knottin-type antifungal peptide from the seeds of Phytolacca americana

The three-dimensional solution structure of PAFP-S, an antifungal peptide extracted from the seeds of Phytolacca americana, was determined using 1H NMR spectroscopy. This cationic peptide contains 38 amino acid residues. Its structure was determined from 302 distance restraints and 36 dihedral restraints derived from NOEs and coupling constants. The peptide has six cysteines involved in three disulfide bonds. The previously unassigned parings have now been determined from NMR data. The solution structure of PAFP-S is presented as a set of 20 structures using ab initio dynamic simulated annealing, with an average RMS deviation of 1.68 A for the backbone heavy atoms and 2.19 A for all heavy atoms, respectively. For the well-defined triple-stranded beta-sheet involving residues 8-10, 23-27, and 32-36, the corresponding values were 0.39 and 1.25 A. The global fold involves a cystine-knotted three-stranded antiparallel beta-sheet (residues 8-10, 23-27, 32-36), a flexible loop (residues 14-19), and four beta-reverse turns (residues 4-8, 11-14, 19-22, 28-32). This structure features all the characteristics of the knottin fold. It is the first structural model of an antifungal peptide that adopts a knottin-type structure. PAFP-S has an extended hydrophobic surface comprised of residues Tyr23, Phe25, Ile27, Tyr32, and Val34. The side chains of these residues are well-defined in the NMR structure. Several hydrophilic and positively charged residues (Arg9, Arg38, and Lys36) surround the hydrophobic surface, giving PAFP-S an amphiphilic character which would be the main structural basis of its biological function.

A depressant insect toxin with a novel analgesic effect from scorpion Buthus martensii Karsch

A new peptide named BmK dITAP3 from scorpion Buthus martensii Karsch (BmK) has been identified to possess a dual bioactivity, a depressant neurotoxicity on insects and an analgesic effect on mice. The bioassays also showed that the peptide was definitely devoid of the neurotoxicity on mammals, which indicated that the analgesic effect of BmK dITAP3 could not be ascribed to the syndromic effects of a mammalian neurotoxicity. BmK dITAP3 exhibited 43.0% inhibition efficiency of the analgesic effect on mice at a dose of 5 mg/kg and the FPU value of 0.5 microg/body (approximately 30 mg) on the fly larvae. The pI value and the molecular mass determined by MALDI-TOF MS for dITAP3 were 6.5 and 6722.7, respectively. Its first 15 N-terminal residues were determined by Edman degradation, based on which the full amino acid sequence was deduced from the cDNA sequence encoding the peptide with 3'-RACE. Circular dichroism and sequence based prediction analyses showed dITAP3 may have a similar molecular scaffold as the most scorpion toxins but with features of the more beta structures and much less of alpha helix. The details of the purification, characterization and sequencing as well as the sequence comparison with other depressant insect toxins and the correlation between the analgesic effect and the insect toxicity will be reported and discussed, respectively.

Crystallization and preliminary X-ray analysis of a depressant insect toxin from the scorpion Buthus martensii Karsch

Depressant insect toxins are a distinct group of scorpion neurotoxins for which no three-dimensional structures are yet available. A depressant insect toxin named BmK dITAP3 from the scorpion Buthus martensii Karsch (BmK) has been purified and crystallized. Single crystals of dITAP3 grew in the presence of the detergent CYMAL-6 using the hanging-drop vapour-diffusion method with ammonium sulfate as precipitant. A set of diffraction data to 2.6 A resolution has been collected. Preliminary analysis of the diffraction data indicated that the crystal belonged to space group R3, with unit-cell parameters a = b = 73.29, c = 68.90 A, alpha = beta = 90, gamma = 120 degrees. Assuming two molecules in the asymmetric unit, the estimated solvent content is 53.4%.

A new insect neurotoxin AngP1 with analgesic effect from the scorpion Buthus martensii Karsch: purification and characterization

An insect toxin named BmK AngP1 was purified from the venom of the scorpion Buthus martensii Karsch (BmK). It also shows an evident analgesic effect on mice, but is interestingly devoid of mammalian toxicity. Bioassay showed that the CPU value of AngP1 was 0.01 microg/body ( approximately 30 mg) for the excitatory insect toxicity and 43.0% inhibition efficiency for analgesia at a dose of 5 mg/kg. However, even at the dosage of 10 mg/kg no detectable toxicity on mice could be found. The isoelectric point (pI) value for AngP1 was 4.0, and its molecular mass analyzed by MALDI-TOF MS was 8141.0. The first 15 N-terminal residues of AngP1 were determined by Edman degradation and showed high similarity to that of other excitatory scorpion insect toxins. The circular dichroism spectroscopy measured on a JASCO J-720 system showed that there were 10.4% alpha-helix, 46.2% beta-strand and 14.1% turn structure in this peptide. Under two conditions single crystals of AngP1 were obtained.

Electrophysiological characterization of BmK M1, an alpha-like toxin from Buthus martensi Karsch venom

The present study investigates the electrophysiological actions of BmK M1, an alpha-like toxin purified from the venom of the scorpion Buthus martensi Karsch, on voltage-gated Na+ channels. Using the voltage clamp technique, we assessed the BmK M1 activity on the cardiac Na+ channel (hH1) functionally expressed in Xenopus oocytes. The main actions of the toxin are a concentration-dependent slowing of the inactivation process and a hyperpolarizing shift of the steady-state inactivation. This work is the first electrophysiological characterization of BmK M1 on a cloned Na+ channel, demonstrating that this toxin belongs to the class of scorpion alpha-toxins. Our results also show that BmK M1 can be considered as a cardiotoxin.

Molecular characterization of an anti-epilepsy peptide from the scorpion Buthus martensi Karsch

For a long time Asian scorpion Buthus martensi Karsch (BmK) has been used in Chinese traditional medicine to cure many diseases of nervous system. Here we report the purification and characterization of a pharmacologically active neurotoxin from the scorpion BmK. This toxin had little toxicity in mice and insects but was found to have an anti-epilepsy effect in rats, and is thus named as BmK anti-epilepsy peptide (BmK AEP). Its amino-acid sequence was determined by lysylendopeptidase digestion, Edman degradation and mass spectrographic analysis. Based on the determined sequence, the gene coding for this peptide was also cloned and sequenced by the 3' and 5' RACE methods. It encodes a precursor of 85 amino-acid residues including a signal peptide of 21 residues, a mature peptide of 61 residues and three additional residues Gly-Lys-Lys at the C-terminus. The additional Gly sometimes followed by one or two basic residues is prerequisite for the amidation of its C-terminus. C-terminal amidation was also verified by the molecular-mass determination of BmK AEP. This anti-epilepsy peptide toxin shares homology with other depressant insect toxins. The remarkable difference between them was mainly focused at residues 6, 7 and 39; these residues might relate to the unique action of BmK AEP.

Scientific basis of spasticity: insights from a laboratory model

A variety of central nervous system injuries, diseases, and developmental deficits can lead to motor disorders that present complex mixtures of symptoms. Those that have a fundamental similarity characterized by the appearance of exaggerated velocity-dependent resistance to the lengthening of skeletal muscles are called spasticity. Reports based on clinical observations of motor disorders have and continue to provide the essential database of information regarding the range and distribution of unifying and discordant features of spasticity. Laboratory investigations employing animal models of motor disorders following experimental lesions of the central nervous system have reproduced some of the neurophysiologic changes that accompany injury of the central nervous system in humans. Those experimental lesions produced by spinal cord contusion/compression reproduce many of the histopathologic features displayed in traumatic injury of the human spinal cord as well. Studies using this model have revealed not only changes in reflex threshold and amplitude but also alterations in fundamental rate-modulation processes that regulate reflex excitability during repetitive stimulation. This report characterizes insights obtained from a laboratory investigation in search of fundamental mechanisms that contribute to the development of spasticity and provides a vantage point for understanding therapeutic strategies for treatment of spasticity.

Crystallization and preliminary X-ray analyses of insect neurotoxins with analgesic effect from the scorpion Buthus martensii Karsch

Three insect neurotoxins from the scorpion Buthus martensii Karsch, named BmK I1, BmK I4 and BmK I6, have been purified and crystallized. BmK I1 and BmK I4 show strong toxicity to insects, while BmK I6 is relatively weaker. They all exhibit an evident analgesic effect on mice; this is a novel biological function for scorpion insect toxins. Their crystals diffract to at least 3.5 (BmK I1), 2.8 (BmK I4), 2.8 (BmK I6 crystal form I) and 2.2 A (of BmK I6 crystal form II) resolution on an ordinary X-ray source. Crystals of BmK I1 belong to space group P6, with unit-cell parameters a = b = 66.2, c = 176.7 A. BmK I4 crystallized in the tetragonal space group I4, with unit-cell parameters a = b = 134.5, c = 60.6 A. BmK I6 has been crystallized in two forms: form I belongs to space group C2, with unit-cell parameters a = 46.5, b = 85.2, c = 32.6 A, beta = 110.5 degrees; form II belongs to space group R3, with the hexagonal unit-cell parameters a = b = 44.5, c = 164.7 A.

Crystallization and preliminary X-ray analysis of the thermostable sweet protein mabinlin II

Mabinlin II is a sweet protein with the highest known thermostablility and is isolated from the seeds of Capparis masaikai Levl. grown in south China. Two crystal forms of mabinlin II were obtained using the hanging-drop vapour-diffusion method. One of them diffracts to 2.8 A resolution and belongs to space group P2, with unit-cell parameters a = 50.16, b = 50.17, c = 76.60 A, beta = 99.6 degrees. There are four molecules per asymmetric unit, with a solvent content of 35.3%.

Conformational correlation and coupled motion between residue A21 and B25 side chain observed in crystal structures of insulin mutants at position A21

The C-terminal residue of the insulin A chain is invariant and kept as asparagine in all known insulin molecules from hagfish through birds to mammals. To get information on the role of this conserved residue, which is still unclear, the three-dimensional structures of four human insulin mutants, A21 Asn-->Gly, A21 Asn-->Asp, A21 Asn-->Ala, and A21 Asn-->Gln DesB30, were determined by X-ray crystallography. The four mutants crystallize separately into two kinds (rhombohedral and cubic) of crystals. In the refined structures, conformational correlation and coupled motion between the A chain C-terminal residue A21 and the B25 side chain was observed, in contrast to the nearly unchanged general structures as compared with the native insulin structures in their respective crystals. A detailed analysis suggests that residue A21 can affect insulin receptor binding by interaction with the B25 side chain and the B chain C-terminal segment to assist the B25 side chain rearranging into the 'active' conformation.

The determination of RWJ-38705 (tramadol N-oxide) and its metabolites in preclinical pharmacokinetic studies using LC-MS/MS

A rapid and reliable analytical method is described for the simultaneous determination of RWJ-38705 (tramadol N-oxide) and several of its major metabolites in the plasma of Sprague-Dawley rats and Beagle dogs. Sample preparation using solid phase extraction was followed by reversed phase liquid chromatography (LC) coupled with tandem mass spectrometric (MS/MS) detection in the positive ionization mode. The assay was linear for all analytes over concentrations ranging from approximately 6 to 2000 ng/ml. The inter-assay reproducibility was generally less than 15% while accuracy values were within 13% of theoretical. The overall recovery of the analytes ranged from approximately 40 to 64% in rat plasma and 53-75% in dog plasma. This assay has proven to be sensitive, specific and reproducible, and it has been readily implemented in preclinical PK studies. Representative plasma concentration versus time profiles resulting from administration of TNO to rats and dogs are presented in this communication.

Structure of a new neurotoxin from the scorpion Buthus martensii Karsch at 1.76 A

A new neurotoxin BmK M2, toxic to both mammals and insects, with the strongest toxicity in the BmK toxin series, has been purified from the Chinese scorpion Buthus martensii Karsch and crystallized with MPD at pH 7.5. The crystals are orthorhombic, belonging to space group P2(1)2(1)2(1), with unit-cell parameters a = 36.64, b = 36.95, c = 37.23 A. The structure was solved by molecular replacement and refined to R = 0.186 for all reflections to a resolution of 1.76 A. The whole sequence (64 residues) of BmK M2 was determined by crystallographic analysis based on high-resolution data and the homologous model of BmK M8. The refined BmK M2 structure shows a non-proline cis peptide bond between Pro9 and His10 which enables the C-terminal segment to adopt a conformation different to that of the weak toxin BmK M8. Recently, a mutation analysis had suggested that both the tenth residue and the C-terminus play key roles in receptor binding. Therefore, these features may be related to the binding selectivity of the group III alpha-like toxins. The charge changes of residues 8, 10, 18, 28, 55 and 59 from neutral or negative to positive or neutral, which leads to a positive electrostatic potential surface, may be responsible for the high toxicity of BmK M2.

Expression and purification of the BmK M1 neurotoxin from the scorpion Buthus martensii Karsch

The gene encoding a neurotoxin (BmK M1) from the scorpion Buthus martensii Karsch was expressed in Saccharomyces cerevisiae at a high level with the alcohol dehydrogenase promoter. SDS-PAGE of the culture confirmed expression and showed secretion into medium from yeast. Recombinant BmK M1 was purified rapidly and efficiently by ion exchange and gel filtration chromatography to homogeneity, produced a single band on tricine-SDS-PAGE, and processed the homologous N-terminus. Amino acid analysis and N-terminal sequencing demonstrated that the recombinant toxin was processed correctly from the alpha-mating factor leader sequence and was chemically identical to the native form. The expressed recombinant BmK M1 was toxic for mice, which indicated that it was biologically active. Quantitative estimation showed that recombinant BmK M1 had an LD(50) similar to that of the native toxin.

A series of bioactivity-variant neurotoxins from scorpion Buthus martensii Karsch: X-ray crystal structure and functional implications

Three bioactivity-variant neurotoxins, BmK M1, M4, and M8, have been purified from venom of the Chinese scorpion Buthus martensii Karsch. They possess distinct toxic activity on mice in vivo with different electrostatic properties. The relative toxicities of BmK M1, M4, and M8 are 13.3:2.5:1, which interestingly correspond to their respective pI values, ranging from basic to acidic, of 9.01, 7.53, and 5.30, respectively. In addition, the X-ray crystal structure of BmK M8, which is acidic and 1100 times less active than the most potent and basic alpha-toxin AaH II, have been determined at 1.85 A resolution and analyzed in detail. In combination with information from chemical modifications and site-directed mutagenesis, the structural comparisons and sequence alignments suggest a multisite binding mode for toxin-receptor interactions, and three "toxic regions" with relevance to the binding process, including Face A, Face B, and Site C. Face A is featured in the presence of several aromatic residues and may be more essential for the binding; Face B may contribute to the high efficacy of the binding process, on which substitution by acidic residues could weaken the toxic activity; Site C is probably involved in binding site specificity. The main residues involved in these regions will be discussed.

Crystal structures of two alpha-like scorpion toxins: non-proline cis peptide bonds and implications for new binding site selectivity on the sodium channel

The crystal structures of two group III alpha-like toxins from the scorpion Buthus martensii Karsch, BmK M1 and BmK M4, were determined at 1.7 A and 1.3 A resolution and refined to R factors of 0.169 and 0.166, respectively. The first high-resolution structures of the alpha-like scorpion toxin show some striking features compared with structures of the "classical" alpha-toxin. Firstly, a non-proline cis peptide bond between residues 9 and 10 unusually occurs in the five-member reverse turn 8-12. Secondly, the cis peptide 9-10 mediates the spatial relationship between the turn 8-12 and the C-terminal stretch 58-64 through a pair of main-chain hydrogen bonds between residues 10 and 64 to form a unique tertiary arrangement which features the special orientation of the terminal residues 62-64. Finally, in consequence of the peculiar orientation of the C-terminal residues, the functional groups of Arg58, which are crucial for the toxin-receptor interaction, are exposed and accessible in BmK M1 and M4 rather than buried as in the classical alpha-toxins. Sequence alignment and characteristics analysis suggested that the above structural features observed in BmK M1 and M4 occur in all group III alpha-like toxins. Recently, some group III alpha-like toxins were demonstrated to occupy a receptor site different from the classical alpha-toxin. Therefore, the distinct structural features of BmK M1 and M4 presented here may provide the structural basis for the newly recognized toxin-receptor binding site selectivity. Besides, the non-proline cis peptide bonds found in these two structures play a role in the formation of the structural characteristics and in keeping accurate positions of the functionally crucial residues. This manifested a way to achieve high levels of molecular specificity and atomic precision through the strained backbone geometry.

Structure of an insulin dimer in an orthorhombic crystal: the structure analysis of a human insulin mutant (B9 Ser-->Glu)

The structure of human insulin mutant B9 (Ser-->Glu) was determined by an X-ray crystallographic method at 2.5 A resolution with an R factor of 0.165 under non-crystallographic restraints. The crystals were grown at low pH (<3.8) and belong to the orthorhombic P2(1)2(1)2(1) space group with unit-cell dimensions a = 44.54, b = 46.40, c = 51.85 A and one dimer per asymmetric unit without further aggregation. The structure in this crystal form can be regarded as a model for a discrete insulin dimer and displays the following features compared with the structure of 2Zn insulin. (i) The overall dimer is expanded and more symmetric. The two A chains are about 2 A more distant from each other, while the two B chains are about 0.8 A further apart. Both monomers are more similar to molecule 1 than molecule 2 of the 2Zn insulin dimer. (ii) The dimer structure is stabilized by protonation and neutralization of the carboxyl groups at lower pH and, in addition, by formation of a hydrogen-bond network among the side chains of residues GluB9, HisB13 and HisB10 on the dimer-forming surface of both monomers, resulting from a structural rearrangement. (iii) The B-chain amino-terminal segment is in an open state (O state), i.e. a state different from the well known R and T states found in the insulin hexamer. In the O state, the B-chain N-terminal segment is in an extended conformation and is detached from the rest of the molecule. This conformational state has also been observed in the monomeric crystal structure of despentapeptide (B26-B30) and desheptapeptide (B24-B30) insulin, as well as in the solution structure of an engineered insulin monomer. It suggests that the O state may be the characteristic conformation of insulin in lower aggregation forms and may be relevant to the formation of insulin fibrils. In addition, based on the crystallization process, the smallest possible building blocks of insulin crystal are also discussed.