[Propensity-matched comparison of laparoscopic and open radical cystectomy for female patients with bladder cancer]

OBJECTIVE

To compare the perioperative and oncologic outcomes of female patients receiving laparoscopic radical cystectomy (LRC) and open radical cystectomy (ORC).

METHODS

Retrospective review of 91 consecutive female patients with urothelial carcinoma of bladder undergoing radical cystectomy at a single academic institution from 2006 to 2017. Those female patients received open radical cystectomy were matched to the patients who underwent laparoscopic radical cystectomy by using propensity score matching in 1 ∶1 ratio. The matching factors included age, body mass index (BMI), American Society of Anesthesiologists (ASA) score, pathologic stage and pathologic nodal stage. The perioperation and oncology characteristics were compared, and Kaplan-Meier method was used to analyze the overall survival (OS), cancer specific survival (CSS) and progression-free survival (PFS) estimates. Finally, we did a sensitive analysis by using multivariable COX regression of all the patients, adjusting for the matching factors.

RESULTS

There were 65 ORC and 26 LRC patients identified in this cohort with urothelial carcinoma of bladder, the median follow-up time was 38 months (interquartile range 18-69). The age (P<0.001) and ASA scores (P=0.018) were less for LRC before being matched. There were 22 LRC and 22 ORC patients matching successfully. Before being matched, the estimate blood loss (P=0.005), transfusion rate (P<0.001) and total complications rate (P=0.015) were less for LRC, and the lymph nodes yield was greater for LRC, but there were no differences in OS (P=0.698), CSS (P=0.942) and PFS (P=0.837) between the two groups. After being matched, the estimate blood loss (P=0.009), transfusion rate (P=0.001) and total complications rate (P=0.040) were less for LRC, but there was no difference in the lymph nodes yield. Besides, there were no statistic differences in OS (P=0.432), CSS (P=0.429) and PFS (P=0.284) between the two groups. In addition, in multivariable COX regression analysis, surgical approaches (LRC/ORC) were not found to be a predictor of OS (HR 1.134, 95%CI 0.335-3.835, P=0.839), CSS (HR 1.051, 95%CI 0.234-4.719, P=0.949) and PFS (HR 0.538, 95%CI 0.138-2.095, P=0.371) of the female patients with urothelial carcinoma of bladder.

CONCLUSION

It is advantageous for laparoscopic radical cystectomy in terms of estimating blood loss, transfusion rate and complication rate. But there was no evidence that laparoscopic radical cystectomy for female patients with bladder cancer had a better oncologic prognosis than open radical cystectomy from this study.

[Advances in surgical repair of ureteral injury]

Ureteral injury can be classified as iatrogenic or traumatic, which represents a rare but challenging field of reconstructive urology. Due to their close proximity to vital abdominal and pelvic organs, the ureters are highly susceptible to iatrogenic injury, while ureteral injury caused by external trauma is relatively rare. The signs of ureteric injury are difficult to identify initially and often present after a delay. The treatment of ureteral injury, which is depended on the type, location, and degree of injury, the time of diagnosis and the patient's overall clinical condition, ranges from simple endoscopic management to complex surgical reconstruction. And long defect of the ureter presents much greater challenges to urologists. Ureterotomy under endoscopy using laser or cold-knife is available for the treatment of 2-3 cm benign ureteral injuries or strictures. Pyeloplasty is an effective treatment for ureteropelvic junction obstruction and some improved methods showed the possibility of repairing long-segment (10-15 cm) stenosis. Proximal and mid-ureteral injuries or strictures of 2-3 cm long can often be managed by primary ureteroureterostomy. When not feasible due to ureteral defects of longer segment, mobilization of the kidney should be considered, and transureteroureterostomy is alternative if the proximal ureter is of sufficient length. And autotransplantation or nephrectomy is regarded as the last resorts. Most of the injuries or strictures are observed in the distal ureter, below the pelvic brim, and are usually treated with ureteroneocystostomy. A non-refluxing technique together with a ureteral nipple or submucosal tunnel method, is preferable as it minimizes vesico-ureteral reflux and the risk of infection. In order to cover a longer distance, ureteroneocystostomy in combination with a psoas hitch (covering 6-10 cm of defect) or a Boari flap (covering 12-15 cm) is often adopted. Among various ureteral replacement procedures, only intestinal ureteral substitution, which includes ileal ureter, appendiceal interposition and reconfigured colon substitution, has gained wide acceptance when urothelial tissue is insufficient. Ileal ureter can be used to replace the ureter of >15 cm defect and even to replace the entire unbilateral ureter or bilateral ureter. Laparoscopic and robotic-assisted techniques are increasingly being employed for ureteral reconstruction and adopted with encouraging results.

Regulatory role of CDX2 and NOX4 expression associated with recurrent nasopharyngeal carcinoma

OBJECTIVE

Nasopharyngeal carcinoma (NPC) is a malignancy caused by Epstein-Barr virus (EBV). NPC is radiosensitive and has a high frequency of treatment failure due to metastasis, which results in recurrent nasopharyngeal carcinoma (rNPC).

PATIENTS AND METHODS

In the present study, nasopharyngeal carcinoma biopsies were obtained from NPC and rNPC patients, as well as healthy controls, and reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, and immunoblotting analyses were performed.

RESULTS

The RTPCR data showed expression of CDX2 and NOX4 in rNPC biopsy samples but not in control or NPC samples. Immunohistochemical and immunoblotting analyses confirmed the expression of CDX2 and NOX4 in rNPC samples, but not in NPC biopsy samples.

CONCLUSIONS

The finding concludes that an association of CDX2 and NOX4 expression with rNPC was noted; thus, these proteins may have value as prognostic indicators and may facilitate the development of novel therapeutics for rNPC patients.

[Gas chromatography-mass spectrometry based urinary metabolomics in very low birth weight premature infants]

Objective: To investigate the urinary metabolic spectrum and pathways in very low birth weight (VLBW) premature infants. Method: A prospective case-control study was conducted to collect and compare the data of VLBW premature infants and full term infants from the Sixth Affiliated Hospital of Sun Yet-Sen University in 2014. Within 24 hours after birth, urine specimens in each group were collected. Metabolites of urine samples including amino acid, fatty acid and organic acid were detected using the urease pre-processing and gas chromatography mass spectrometry (GC-MS) technology. Using the orthogonal partial least squares discriminant analysis (OPLS-DA), the biomarkers and differences between the two groups were found. The online metabolic pathway website was explored and multivariable analysis was conducted to investigate the valuable pathways and biomarkers related to the prematurity. Result: A total of 20 VLBW premature infants were enrolled, among whom 11 were male, 9 were female; and 20 full term infants were enrolled, among whom 9 were male, 11 were female. The urinary metabolites were established and compared between the VLBW premature and term infants. The investigation showed that the following nine pathways were enriched: amino-acyl-tRNA biosynthesis(P=0.000), lysine degradation(P=0.007), fatty acid biosynthesis(P=0.008), pyrimidine metabolism(P=0.014), pantothenate and CoA biosynthesis(P=0.022), valine, leucine and isoleucine biosynthesis(P=0.022), lysine biosynthesis(P=0.031), glycerolipid metabolism(P=0.046), and valine, leucine and isoleucine degradation(P=0.031). Almost all the metabolites decreased except for the glyceric acid exhibiting a higher content in the VLBW premature infant. 12 potential biomarkers were explored with the most significant covariance and correlation, within which stearic acid, palmiticacid, myristic acid, β-amino-isobutyric acid, and uric acid were lower, while myo-inositol, mannitol, glycine, glucose1, glucose2, glyceric acid and N-acetyl-tyrosine were higher in the VLBW premature group compared with the control group. Conclusion: There is a significant difference between the VLBW premature infants and full-term infants in the metabolic state and pathways. The urease pre-processing and GC-MS technology followed by the OPLS-DA and multivariable analysis to investigate VLBW premature infants' urinary metabolites is a valuable method to evaluate the patients' metabolism.

Pharmacokinetic and pharmacodynamic integration and modeling of acetylkitasamycin in swine for Clostridium perfringens

The aim of this study was to establish an integrated pharmacokinetic/pharmacodynamic (PK/PD) modeling approach of acetylkitasamycin for designing dosage regimens and decreasing the emergence of drug-resistant bacteria. After oral administration of acetylkitasamycin to healthy and infected pigs at the dose of 50 mg/kg body weights (bw), a rapid and sensitive LC-MS/MS method was developed and validated for determining the concentration change of the major components of acetylkitasamycin and its possible metabolite kitasamycin in the intestinal samples taken from the T-shape ileal cannula. The PK parameters, including the integrated peak concentration (C_max ), the time when the maximum concentration reached (T_max ) and the area under the concentration-time curve (AUC), were calculated by WinNonlin software. The minimum inhibitory concentration (MIC) of 60 C. perfringens strains was determined following CLSI guideline. The in vitro and ex vivo activities of acetylkitasamycin in intestinal tract against a pathogenic strain of C. perfringens type A (CPFK122995) were established by the killing curve. Our PK data showed that the integrated C_max , T_max , and AUC were 14.57-15.81 μg/ml, 0.78-2.52 hR, and 123.84-152.32 μg hr/ml, respectively. The PD data show that MIC₅₀ and MIC₉₀ of the 60 C. perfringens isolates were 3.85 and 26.45 μg/ml, respectively. The ex vivo growth inhibition data were fitted to the inhibitory sigmoid E_max equation to provide the values of AUC/MIC to produce bacteriostasis (4.84 hr), bactericidal activity (15.46 hr), and bacterial eradication (24.99 hr). A dosage regimen of 18.63 mg/kg bw every 12 hr could be sufficient in the prevention of C. perfringens infection. The therapeutic dosage regimen for C. perfringens infection was at the dose of 51.36 mg/kg bw every 12 hr for 3 days. In summary, the dosage regimen for the treatment of C. perfringens in pigs administered with acetylkitasamycin was designed using PK/PD integrate model. The designed dose regimen could to some extent decrease the risk for emergence of macrolide resistance.

Long noncoding RNAs as novel serum biomarkers for the diagnosis of hepatocellular carcinoma: a systematic review and meta-analysis

PURPOSE

Long noncoding RNAs (lncRNAs) are outstanding as novel cancer biomarkers with great prospects. Herein, we focused on summarizing the overall diagnostic evaluation of lncRNAs for hepatocellular carcinoma (HCC).

METHODS

Relevant literature was collected from the online databases. The Quality Assessment for Studies of Diagnostic Accuracy checklist was used to assess the quality of included studies. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were plotted using random-effects models. Summary receiver operating characteristic curve and the area under the curve (AUC) were used to estimate the overall test performance. Statistical analysis was performed by STATA 14.0 and Meta-DiSc 1.4 software.

RESULTS

Ten studies with a total of 820 HCC patients and 785 healthy controls were included. For overall lncRNAs, the pooled sensitivity, specificity, and DOR to predict HCC patients were 80% [95% confidence interval (CI) 77-82%], 79% (95% CI 76-81%), and 27.66 (95% CI 14.26-53.63), respectively, corresponding to an AUC of 0.91.

CONCLUSIONS

LncRNAs were a high diagnostic value for HCC and its expression could potentially be used as auxiliary biomarker in confirming HCC.

[Effect of gum chewing on bowel function recovery in patients after radical cystectomy with urinary diversion]

OBJECTIVE

To determine whether chewing gum during the postoperative period facilitates the recovery of bowel function in patients after radical cystectomy with ileum urinary diversion.

METHODS

In the study, 60 patients who underwent radical cystectomy followed by ileum urinary diversions during Nov. 2014 and Nov. 2015 in Department of Urology of Peking University First Hospital were randomized into three groups: gum chewing group, placebo group treated with the abdomen physical therapy machine and control group treated with ordinary method. Time to flatus, time to bowel movement, incidence of postoperative distension of the abdomen and abdominal pain, and gut related complications (such as ileus, intestinal fistula, and volrulus) of all the patients were recorded and analysed.

RESULTS

In gum chewing group, the median time to flatus was 57 hours (49-72 hours), and the median time to bowel movement was 95 hours (88-109 hours), which were significantly shortened compared with the other two groups of patients (82 hours, 109 hours in placebo group and 81 hours, 108 hours in control group, respectively). No significant difference of the median time to flatus and to bowel movement was observed between placebo group and control group. There were no significant differences in the incidence of postoperative distension of the abdomen and abdominal pain, and gut related complications among the three groups.

CONCLUSION

Chewing gum had stimulatory effect on bowel function recovery after cystectomy followed by ileum urinary diversion. Chewing gum was safe and simple, and could be routinely used for postoperative treatment after cystectomy and ileum urinary diversion.

[Radical cystectomy in patients with pathological non-muscle invasive bladder cancer]

OBJECTIVE

Carcinoma of bladder is the most common malignancy in the urinary system in China. Most patients with this disease had non-muscle invasive bladder cancer (NMIBC) at the time of diagnosis. Radical cystectomy was indicated for patients with high risk or refractory NMIBC. We aimed to investigate the overall survival and disease-specific survival and related influence factors in patients undergoing radical cystectomy for pathological non-muscle invasive bladder cancer.

METHODS

From Jan. 2006 to Dec. 2012, a total of 164 patients with pathological non-muscle invasive bladder cancer underwent radical cystectomy in Peking University First Hospital. Clinical data were retrospectively collected.Incidence of lymph node metastasis and disease recurrence were calculated. The risk factors of disease recurrence were analyzed. Kaplan-Meier plots were used to estimate the overall survival and cancer-specific survival. Multivariate Cox regression analysis was used to evaluate the prognostic factors for survival.

RESULTS

Of all the patients included, 159 had T1 disease, and 5 had CIS only. The median follow-up duration was 46.5 months (range: 7-99 months). Fourteen patients were lost during the follow-up. Lymph node metastasis was noted in 6 patients (3.7%), 4 patients had N1 disease, one patient had N2 disease, and one patient had N3 disease. Disease recurrence occurred in 16 patients (9.8%).The most common recurrence sites were the liver, bones, and lungs. The 5-year overall survival and disease-specific survival for all the patients were 85% and 91%, respectively. The patients who underwent pelvic lymph node dissection showed a better prognosis in terms of disease-specific survival than those without (P=0.012). Patients with recurrence harbored a significant poorer survival (P<0.001). According to univariate Cox regression analysis, whether lymph node dissection was performed was an independent risk factor of disease recurrence (P=0.050, OR=2.695, 95%CI 0.999-7.271). In COX regression model, age (P=0.008, OR=1.071, 95%CI 1.018-1.126) and whether lymph node dissection was performed (P=0.011, OR=3.385, 95%CI 1.329-8.621) were related to disease-specific survival.

CONCLUSION

Patients with pathological non-muscle invasive bladder cancer underwent early radical cystectomy have a favorable prognosis, and bilateral pelvic lymph node dissection is essential for this procedure as it gains a survival benefit for the patients.

Meta-analysis of alkaline phosphatase and prognosis for osteosarcoma

Many studies have evaluated the relationships between alkaline phosphatase (ALP) levels and the prognosis for osteosarcoma. However, a consensus has yet to be reached. We completed a meta-analysis to assess the significance of ALP and prognosis for osteosarcoma. We retrieved eligible documents from the PubMed and Embase databases and extracted related data from those documents. The overall survival (OS), hazard ratio (HR) and event-free survival (EFS) HR were obtained after combination to evaluate the impacts of ALP levels on prognosis for osteosarcoma. After screening, a total of 12 documents published between 1999 and 2013 were included. The ALP levels on OS were evaluated in nine documents. The pooled HRs was 1.78 (95% CI: 1.52-2.07, p < .05). The ALP levels on EFS were determined in eight documents. The pooled HRs was 1.58 (95% CI: 1.37-1.82, p < .05). Begg's test (OS, p > .754; EFS, p > .386) and Egger's test (OS, p > .649; EFS, p > .274) showed that there was no significant publication bias during analytic process. In summary, our meta-analysis shows that a higher level of ALP can decrease the OS and EFS in patients with osteosarcoma and ALP is an important biological indicator for patients with osteosarcoma.

[Radical cystectomy in patients with pathological non-muscle invasive bladder cancer]

OBJECTIVE

Carcinoma of bladder is the most common malignancy in the urinary system in China. Most patients with this disease had non-muscle invasive bladder cancer (NMIBC) at the time of diagnosis. Radical cystectomy was indicated for patients with high risk or refractory NMIBC. We aimed to investigate the overall survival and disease-specific survival and related influence factors in patients undergoing radical cystectomy for pathological non-muscle invasive bladder cancer.

METHODS

From Jan. 2006 to Dec. 2012, a total of 164 patients with pathological non-muscle invasive bladder cancer underwent radical cystectomy in Peking University First Hospital. Clinical data were retrospectively collected.Incidence of lymph node metastasis and disease recurrence were calculated. The risk factors of disease recurrence were analyzed. Kaplan-Meier plots were used to estimate the overall survival and cancer-specific survival. Multivariate Cox regression analysis was used to evaluate the prognostic factors for survival.

RESULTS

Of all the patients included, 159 had T1 disease, and 5 had CIS only. The median follow-up duration was 46.5 months (range: 7-99 months). Fourteen patients were lost during the follow-up. Lymph node metastasis was noted in 6 patients (3.7%), 4 patients had N1 disease, one patient had N2 disease, and one patient had N3 disease. Disease recurrence occurred in 16 patients (9.8%).The most common recurrence sites were the liver, bones, and lungs. The 5-year overall survival and disease-specific survival for all the patients were 85% and 91%, respectively. The patients who underwent pelvic lymph node dissection showed a better prognosis in terms of disease-specific survival than those without (P=0.012). Patients with recurrence harbored a significant poorer survival (P<0.001). According to univariate Cox regression analysis, whether lymph node dissection was performed was an independent risk factor of disease recurrence (P=0.050, OR=2.695, 95%CI 0.999-7.271). In COX regression model, age (P=0.008, OR=1.071, 95%CI 1.018-1.126) and whether lymph node dissection was performed (P=0.011, OR=3.385, 95%CI 1.329-8.621) were related to disease-specific survival.

CONCLUSION

Patients with pathological non-muscle invasive bladder cancer underwent early radical cystectomy have a favorable prognosis, and bilateral pelvic lymph node dissection is essential for this procedure as it gains a survival benefit for the patients.

Widely Tunable Two-Color Free-Electron Laser on a Storage Ring

With a wide wavelength tuning range, free-electron lasers (FELs) are well suited for producing simultaneous lasing at multiple wavelengths. We present the first experimental results of a novel two-color storage ring FEL. With three undulators and a pair of dual-band mirrors, the two-color FEL can lase simultaneously in infrared (IR) around 720 nm and in ultraviolet (UV) around 360 nm. We have demonstrated independent wavelength tuning in a wide range (60 nm in IR and 24 nm in UV). We have also realized two-color harmonic operation with the UV lasing tuned to the second harmonic of the IR lasing. Furthermore, we have demonstrated good power stability with two-color lasing, and good control of the power sharing between the two colors.

Identification of Campylobacter jejuni and determination of point mutations associated with macrolide resistance using a multiplex TaqMan MGB real-time PCR

AIMS

The aim of the study was to develop a multiplex real-time PCR method to identify Campylobacter jejuni containing mutations commonly associated with macrolide resistance.

METHODS AND RESULTS

A multiplex fluorescence real-time PCR assay was developed based on TaqMan minor groove binder (MGB) probes. The VS1-MGB probe was designed based on the VS1 gene and was used to identify Camp. jejuni. The 23S rDNA-MGB probe was designed to distinguish macrolide resistance mutations in 23S rDNA, while 57D-MGB and 74D-MGB were designed to detect resistance mutations in ribosomal protein L4. The specificity and accuracy of our method were identical to the conventional biochemical tests, mapA PCR, minimum inhibitory concentration (MIC) determination and DNA sequencing. The linear detection limit of the method was 0·03 ng genomic DNA and three colony formation unit (CFU) per reaction. In 6 of 18 cases, the nature of Erythromycin resistance could be correctly determined from natural isolates; absence of the tested mutations was demonstrated in the remaining four resistant isolates.

CONCLUSIONS

A multiplex TaqMan MGB real-time PCR assay with high specificity and accuracy was developed to simultaneously identify Camp. jejuni and detect the gene mutations associated with macrolide resistance.

SIGNIFICANCE AND IMPACT OF THE STUDY

This multiplex method can potentially simplify the identification of Camp. jejuni and determine macrolide resistance due to mutations in 23S rDNA or ribosomal protein L4. This method has a potential for application in different research areas and molecular surveillance.

Prevalence of myasthenia gravis and associated autoantibodies in paraneoplastic pemphigus and their correlations with symptoms and prognosis

BACKGROUND

Paraneoplastic pemphigus (PNP) involves multiple organs, but little is known about its neurological involvement.

OBJECTIVES

To investigate the symptoms, prognosis and profiles of associated autoantibodies in myasthenia gravis (MG), and their correlations in patients with PNP.

METHODS

Fifty-eight patients with PNP were assessed for myasthenic symptoms and laboratory evidence. Serum autoantibodies against acetylcholine receptor (AChR), acetylcholinesterase (AChE), titin, ryanodine receptor (RyR) and muscle-specific kinase (MuSK) were measured by enzyme-linked immunosorbent assay. Patients with pemphigus vulgaris (PV), pemphigus foliaceus (PF), connective tissue disease (CTD) and non-PNP MG (NP-MG), and healthy donors, served as controls. These autoantibodies in PNP were also compared in the presence or absence of dyspnoea or muscle weakness. Cox regression and log-rank tests were used for survival analysis.

RESULTS

Overall 39% of patients with PNP experienced muscle weakness, and 35% were diagnosed with MG. Moreover, 35% had positive anti-AChR and 28% had anti-AChE antibodies, similarly to NP-MG (33% and 17%, respectively, P > 0·05). However, both were negative in all patients with PV, PF and CTD and healthy donors (P < 0·005). No other antibodies showed significant differences among groups. Anti-AChR and anti-AChE antibody levels were significantly increased in patients with PNP with dyspnoea, while anti-AChR, anti-titin and anti-RyR were significantly increased in patients with PNP with muscle weakness (P < 0·05). Nevertheless, levels and positive rates of these autoantibodies showed no significant differences between PNP with Castleman disease and thymoma. Although anti-AChE levels impacted survival duration (P  =  0·027, odds ratio 3·14), MG complications did not affect the overall survival percentage in PNP.

CONCLUSIONS

MG is a complication of PNP. Anti-AChR and anti-AChE antibodies are prominent in patients with PNP, especially those with dyspnoea.

Maternal and paternal diversity in Xinjiang Kazakh population from China

The ancient silk road of China passed through Xinjiang and facilitated gene exchanges from the East and the West which impacted on the genetic variation and structure of the nomadic Kazakh population residing there. In order to understand the nature of this genetic variation; 151 Xinjiang Kazakh samples were obtained from four main Kazakh groups and were analyzed using mtDNA and Y-chromosome markers. The Xinjiang Kazakh population is heterogeneous, showing the coexistence of matrilineal lineages with different origins. No genetic differentiation of mtDNA is observed among the four different regional Xinjiang Kazakh populations in Xinjiang by AMOVA and Networks. The genetic diversity of Y-STR loci is higher in Xinjiang Kazakhs (0.968 ± 0.014) than the Kazakhs from Kazakhstan (0.629 ± 0.071) and Russia (0.835 ± 0.020). East Eurasians make a more than 50% contribution to the maternal and paternal lineages of Xinjiang Kazakhs. There is more gene flow from West Eurasian into the maternal lineages of Xinjiang Kazakh than to the Kazakhs from Russia and Kazakhstan. Moreover, mtDNA and Y-STR displayed high polymorphism in Xinjiang Kazakhs (the haplotype diversity and power of discrimination were 0.990 ± 0.003, 0.9137 for mtDNA HVS and 0.968 ± 0.014, 0.9489 for Y-STR system, respectively), suggesting they would be very useful and important markers for forensic analysis and population genetic studies.

Genomic organization and expression of immunoglobulin genes in the Chinese hamster (Cricetulus griseus)

In science, the hamsters are widely used as a model for studying the human diseases because they display many features like humans. The utility of the Chinese hamster as a biology model can be further enhanced by further characterization of the genes encoding components of the immune system. Here, we report the genomic organization and expression of the Chinese hamster immunoglobulin heavy and light chain genes. The Chinese hamster IgH locus contains 268 VH segments (132 potentially functional genes, 12 ORFs and 124 pseudogenes), 4 DH segments, 6 JH segments, four constant region genes (μ, γ, ε and α) and one reverse δ remnant fragment. The Igκ locus contains only a single Cκ gene, 4 Jκ segments and 48 Vκ segments (15 potentially functional genes and 33 pseudogenes), whereas the Igλ locus contains 4 Cλ genes, but only Cλ 3 and Cλ 4 each preceded by a Jλ gene segment. A total of 49 Vλ segments (39 potentially functional genes, 3 ORFs and 7 pseudogenes) were identified. Analysis of junctions of the recombined V(D)J transcripts reveals complex diversity in both expressed H and κ sequences, but the microhomology-directed VJ recombination obviously results in very limited diversity in the Chinese hamster λ gene despite more potential germline-encoded combinatorial diversity. This is the first study to make a comprehensive analysis of the Ig genes in the Chinese hamster, which provides insights into the Ig genes in placental mammals.

A novel microbead-based microfluidic device for rapid bacterial identification and antibiotic susceptibility testing

Effective treatment of infectious diseases depends on the ability to rapidly identify the infecting bacteria and the use of sensitive antibiotics. The currently used identification assays usually take more than 72 h to perform and have a low sensitivity. Herein, we present a microbead-based microfluidic platform that is highly sensitive and rapid for bacterial detection and antibiotic sensitivity testing. The platform includes four units, one of which is used for bacterial identification and the other three are used for susceptibility testing. Our results showed that Escherichia coli O157 at a cell density range of 10(1)-10(5) CFU/μL could be detected within 30 min. Additionally, the effects of three antibiotics on E. coli O157 were evaluated within 4-8 h. Overall, this integrated microbead-based microdevice provides a sensitive, rapid, reliable, and highly effective platform for the identification of bacteria, as well as antibiotic sensitivity testing.

Electron transport enhanced by electrode surface reconstruction: a case study of C60-based molecular junctions

At the C₆₀–Cu(111) interface, electrode surface reconstruction (Rec) increases electrical current compared to that for the unreconstructed (Unrec) surface.

Tuning the electron transport properties of boron-nitride nanoribbons with electron and hole doping

C chain doped BN nanoribbons can be either metallic or semiconducting, depending on how the C chains are located.