[Epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023]

Objective: To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023. Methods: The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed. Results: A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M (Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant (P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age (P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion: Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

Estimating Potential Benefits of Online Adaptive Proton Therapy for Head-and-Neck Cancer: A Retrospective Study

PURPOSE/OBJECTIVE(S)

Proton therapy is highly sensitive to anatomical changes and setup variations in head-and-neck (HN) treatments. To address this issue, proton centers often acquire patient CT images weekly to monitor patient anatomical changes during the treatment course and perform offline plan adaptation when needed. However, offline adaptation cannot fully account for daily setup variations or the anatomical changes occurring with high frequency. There are a few groups endeavoring to develop advanced technologies to enable online adaptive proton therapy (APT). However, the necessity of online APT remains controversial, as it is unknown that whether online APT will significantly improve treatment quality and outcomes compared to offline APT. The purpose of this study is to estimate the clinical potential of online APT in the management of HN cancers in relation to the current offline APT.

MATERIALS/METHODS

Our retrospective study was conducted with four HN patients (35 fractions per patient), who had been treated with intensity modulated proton therapy and had offline adaptation once or twice during their treatment courses. Synthetic CT (sCT) images were generated from 140 daily CBCT images for us to recalculate the dose of the treatment plan in patient's actual treatment anatomy for each treatment fraction and adapt the plan when warranted. These adaptations were assumed to be performed online before treatment delivery to mimic an online APT course. Accumulative doses were calculated for both courses using the CBCT-based sCT images of every fraction for us to compare the target coverage, organ at risk (OAR) sparing, tumor control probability (TCP) and normal tissue complication probability (NTCP). An in-house script was developed to semi-automate this process in a commercial treatment planning system to facilitate our study.

RESULTS

All patients would benefit from online APT to different extents. For the first patient, with OAR doses comparable to the actual offline course, the retrospective online APT course improved dose coverages of the three CTVs from 95.2%, 98.64% and 89.53% to 98.88%, 99.81%, 98.97%, which would lead to a 4.52% improvement in TCP. Similarly, online APT would yield a 2.66% improvement in TCP for the second patient. For the third patient, with comparable CTV dose coverages, the mean doses of right parotid and oral cavity were decreased from 29.52 Gy relative biological effectiveness (RBE) and 41.89 Gy RBE to 22.16 Gy RBE and 34.61 Gy RBE, leading to a reduce of 1.67% and 3.40% in NTCP. The mean dose of right parotid was decreased from 21.71 Gy RBE to 19.37 Gy RBE for the last patient, leading to a reduce of 0.73% in NTCP.

CONCLUSION

Our results showed that online APT could better maintain the treatment plan quality than offline APT for all the four patients, despite their significant anatomical changes. Future investigation will focus on collecting more patient data to obtain statistically significant results and help identify the patients to whom the online APT will be of most benefit.

[Characteristics and diversity of infectious diarrheal caused by various pathogens]

Objective: To understand the characteristics and differences of diarrhea-related symptoms caused by different pathogens, and the clinical features of various pathogens causing diarrhea. Methods: Etiology surveillance program was conducted among 20 provinces of China from 2010 to 2016. The acute diarrhea outpatients were collected from clinics or hospitals. A questionnaire was used to survey demographics and clinical features. VFeces samples were taken for laboratory detection of 22 common diarrhea pathogens, to detect and analyze the clinical symptom pattern characteristics of the patient's. Results: A total of 38 950 outpatients were enrolled from 20 provinces of China. The positive rates of Rotavirus and Norovirus were the highest among the five diarrhea-causing viruses (Rotavirus: 18.29%, Norovirus: 13.06%). In the isolation and culture of 17 diarrhea-causing bacterial, Escherichia coli showed the highest positive rates (6.25%). The clinical features of bacterial diarrhea and viral diarrhea were mainly reflected in the results of fecal traits and routine examination, but pathogenic Vibrio infection was similar to viral diarrhea. Conclusion: Infectious diarrhea presents different characteristics due to various symptoms which can provide a basis for clinical diagnosis.

[Analysis on genetic characteristics of H9N2 avian influenza virus isolated from human infection and external environment in Gansu province]

Objective: To analyze the genomic characteristics of human infection with H9N2 avian influenza virus in Gansu province. Methods: The etiological analysis was conducted for human infection with H9N2 avian influenza virus detected in influenza like illness cases in northwestern China in 2016. Molecular bioinformatics Mega 7.0 software was used to analyze the full genomic sequences of the viral isolate. Results: The gene fragments of HA, NA, MP, NP, NS, PA, PB1 and PB2 of the isolate were highly similar (>90%) to those of H9N2 avian influenza virus strain isolated in external environment in Gansu from 2014 to 2019. The HA gene belonged to BJ/94-like branch, PB2 and MP belonged to G1/97-like branch, and the PB1, PA, NS, and NP genes belonged to F/98-like branch. MP and PB2 were closely related to H7N9, H10N8 and H5N6 viruses. Amino acid sequence alignment showed that the HA cleavage site was arranged in PSRSSR ↓ GLF, H183N and Q226L mutated which included 7 HA glycosylated sites; 62-64 sites of NA absented 3 amino acids (ITE); and M2-31N, NS1-42S, PA-356R, and PA-409N mutated. Conclusions: Apparently, this case of human infection with human infection with H9N2 avian influenza virus was an incidental. However, the isolates of H9N2 influenza virus in external environment of Gansu had a series of mammalian adaptive molecular markers, suggesting that the risk of human infection is higher. It is necessary to strengthen the surveillance by multi departments to deal with influenza pandemic.

[Analysis of the first cluster of cases in a family of COVID-19 in Gansu Province]

The epidemiological history and clinical characteristics of 7 cases of COVID-19 and 1 case of close contact in the first family aggregation epidemic of COVID-19 in Gansu Province were analyzed. The first patient A developed on January 22, 2020, with a history of residence in Wuhan, and confirmed severe cases of NCP on January 24, 2020; patient B, on January 23, 2020, diagnosed on January 31, severe cases; patient C, asymptomatic, diagnosed on January 27; patient D, asymptomatic, diagnosed on January 27; patient E, on January 24, diagnosed on January 28; patient F, asymptomatic, diagnosed on January 31; Patient G was asymptomatic and was diagnosed on January 31. In close contact, H was asymptomatic, PCR test was negative and asymptomatic, and he was discharged early. Among the 7 patients, 1 case died of (B) aggravation, and the other patients' condition was effectively controlled after active treatment. Except for the discharged cases, 5 cases were positive for COVID-19 specific IgM antibody and 1 case was negative. In this clustering outbreak, 4 patients remained asymptomatic, but PCR and IgM antibodies were positive, indicating that asymptomatic patients may be the key point to control the epidemic. Specific IgM antibody screening for patients whose pharyngeal swab nucleic acid test is negative but with ground glass-like lung lesions is very important for early detection and early isolation.

[Epidemiological characteristics of COVID-19 in Gansu province]

Objective: To understand the epidemiological characteristics of COVID-19 cases in different epidemic stages in Gansu province. Methods: Epidemiological investigation was conducted to collect the information of confirmed COVID-19 cases, including demographic, epidemiological and clinical information. Results: As of 25 February 2020, a total of 91 confirmed COVID-19 cases had been reported in Gansu. The epidemic of COVID-19 in Gansu can be divided as three different stages, i.e. imported case stage, imported-case plus indigenous case stage, and indigenous case stage. A total of 63 cases were clustered cases (69.23%), 3 cases were medical staff infected with non-occupational exposure. The initial symptoms included fever (54.95%, 50/91), cough (52.75%, 48/91), or fatigue (28.57%, 26/91), the proportion of each symptom showed a decreasing trend along with the three epidemic stages, but only the differences in proportions of fever (trend χ2=2.20, P<0.05) and fatigue (trend χ2=3.18, P<0.05) among the three epidemic stages were statistically significant. The cases with critical severe symptoms accounted for 42.85% (6/14), 23.73% (14/59) and 16.67% (3/18), respectively, in three epidemic stages, showed a decreasing trend (H=6.45, P<0.05). Also, the incubation period prolonged along with the epidemic stage (F=51.65, P<0.01), but the intervals between disease onset and hospital visit (F=5.32, P<0.01), disease onset and diagnosis (F=5.25, P<0.01) became shorter along with the epidemic stage. Additionally, the basic reproduction number (R0) had decreased from 2.61 in imported case stage to 0.66 in indigenous case stage. Conclusions: The COVID-19 epidemic in Gansu was caused by the imported cases, and about 2/3 cases were clustered ones. No medical worker was observed to be infected by occupational exposure. With the progression of COVID-19 epidemic in Gansu, the change in initial symptom and incubation period suggests, the early screening cannot only depend on body temperature monitoring.

[Analysis of the first cluster of cases in a family of novel coronavirus pneumonia in Gansu Province]

The epidemiological history and clinical characteristics of 7 cases of COVID-19 and 1 case of close contact in the first family aggregation epidemic of COVID-19 in Gansu Province were analyzed. The first patient A developed on January 22, 2020, with a history of residence in Wuhan, and confirmed severe cases of NCP on January 24, 2020; patient B, on January 23, 2020, diagnosed on January 31, severe cases; patient C, asymptomatic, diagnosed on January 27; patient D, asymptomatic, diagnosed on January 27; patient E, on January 24, diagnosed on January 28; patient F, asymptomatic, diagnosed on January 31; Patient G was asymptomatic and was diagnosed on January 31. In close contact, H was asymptomatic, PCR test was negative and asymptomatic, and he was discharged early. Among the 7 patients, 1 case died of (B) aggravation, and the other patients' condition was effectively controlled after active treatment. Except for the discharged cases, 5 cases were positive for COVID-19 specific IgM antibody and 1 case was negative. In this clustering outbreak, 4 patients remained asymptomatic, but PCR and IgM antibodies were positive, indicating that asymptomatic patients may be the key point to control the epidemic. Specific IgM antibody screening for patients whose pharyngeal swab nucleic acid test is negative but with ground glass-like lung lesions is very important for early detection and early isolation.

[Epidemiological and spatial-temporal distribution of several natural focus diseases in Gansu province, 2014-2018]

Objective: To analyze the epidemiological and spatial-temporal distribution of Brucellosis, epidemic encephalitis B and hemorrhagic fever with renal syndrome (HFRS) in Gansu province during 2014-2018 so as to provide evidence for the prevention and control of those diseases. Methods: A database was established in Gansu province from 2014 to 2018, using the geographical information system. A spatial distribution map was drawn, with trend analysis and space-time clustering used to study the 3-dimention of the diseases, by using both ArcGIS 10.5 and SaTScan 9.6 softwares. Results: Results from the trend surface analysis showed that the incidence of Brucellosis decreased gradually from north to south parts while the U type curve could reflect the distribution from the east to the west areas. Incidence of epidemic encephalitis B decreased significantly from south to north areas in the province, with incidence higher in the eastern than in the mid-west region. Difference on the incidence of HFRS was not significantly visible in the eastern and western regions, while the incidence was slightly higher in the southern than the northern parts of the province. Spatial and space-time clustering did exist among the 3 diseases in Gansu from 2014 to 2018. The areas with clusters of Brucellosis appeared in the eastern parts during 2014-2015, including 19 counties. The areas with secondary clusters of Brucellosis were seen in the Hexi district, including 4 counties, during 2017-2018. The areas with high incidence of epidemic encephalitis B were clustered in the middle and southeast areas, including 32 counties, during 2017-2018. Areas with most clusters of HFRS appeared in Min county of Dingxi city in 2018, with the areas of secondary clusters in 8 counties of the eastern areas in 2018. Conclusions: The overall incidence rates of the 3 natural focus diseases were in a upward trend and showing obvious characteristics on spatial clustering. According to the distributive characteristics, effective measures should be developed accordingly.

DNA Repair: Translation to the Clinic

It has been well established that an accumulation of mutations in DNA, whether caused by external sources (e.g. ultraviolet light, radioactivity) or internal sources (e.g. metabolic by-products, such as reactive oxygen species), has the potential to cause a cell to undergo carcinogenesis and increase the risk for the development of cancer. Therefore, it is critically important for a cell to have the capacity to properly respond to and repair DNA damage as it occurs. The DNA damage response (DDR) describes a collection of DNA repair pathways that aid in the protection of genomic integrity by detecting myriad types of DNA damage and initiating the correct DNA repair pathway. In many instances, a deficiency in the DDR, whether inherited or spontaneously assumed, can increase the risk of carcinogenesis and ultimately tumorigenesis through the accumulation of mutations that fail to be properly repaired. Interestingly, although disruption of the DDR can lead to the initial genomic instability that can ultimately cause carcinogenesis, the DDR has also proven to be an invaluable target for anticancer drugs and therapies. Making matters more complicated, the DDR is also involved in the resistance to first-line cancer therapy. In this review, we will consider therapies already in use in the clinic and ongoing research into other avenues of treatment that target DNA repair pathways in cancer.

Abstract P1-06-01: Regulation of BRCA1 by SIRT2

We are constantly exposed to a variety of both external and internal DNA damaging agents, such as UV light from the sun and reactive oxygen species created as by-products of aerobic respiration. As a result, our DNA accumulates thousands of instances of damage per cell per day. DNA damage response (DDR) pathways, which include DNA repair and cell-cycle checkpoints, are responsible for the repair of DNA damage and are critical for protecting against mutagenesis and maintaining genome integrity. DNA double-stranded breaks (DSBs) are the most deleterious type of DNA damage and are repaired by one of two pathways: Non-homologous end-joining (NHEJ), an error-prone mechanism of repair active throughout the entire cell cycle, or homologous recombination (HR), considered to be an 'error-free' method for DSB repair that occurs in the S and G2 phases of the cell cycle. Deficiencies in NHEJ or HR can result in genomic instability via genomic incorporation of chromosomal aberrations, which can ultimately lead to an increased risk of cancer. However, in many cases, the mechanisms by which defects in these pathways lead to an increased risk of developing cancer is unknown, making preventative care and treatment of resulting cancers more difficult. Breast Cancer 1 (BRCA1), an established tumor suppressor, is a protein necessary for the proper repair of DNA DSBs through the HR pathway. Defects in BRCA1, whether genetically inherited or spontaneously developed, have been linked to different types of cancer in both men and women, including breast, ovarian, and pancreatic cancer. Yet, the regulation of BRCA1 in HR is not well understood and thus highlights a major a gap in our understanding of how deficiencies in HR contribute to the development of cancer. Our lab has discovered that SIRT2, a class III NAD+ dependent histone deacetylase and putative human tumor suppressor, plays a crucial role in the DDR and repair of DNA DSBs. We have shown that depletion of SIRT2 impairs HR and increases cell sensitivity to ionizing radiation in a deacetylase-dependent manner. A mass spectrometry analysis showed SIRT2 interacts with several proteins involved in DDR, including BRCA1. We validated the interaction between SIRT2 and BRCA1 and found SIRT2 deacetylates BRCA1 both in vitro and in cells. Depletion of SIRT2 and subsequent deacetylation of BRCA1 decreases BRCA1 protein levels in cells, impairing HR. Our results show SIRT2 is a novel regulator of BRCA1 and is critical for the repair of DNA DSBs through HR. These findings provide invaluable insights into how to exploit the interplay between SIRT2 and BRCA1 as a novel therapeutic approach for the prevention and treatment of cancer.

Citation Format: Minten EV, Zhang H, Li C, Head PE, Yu DS. Regulation of BRCA1 by SIRT2 [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-06-01.

[Application of surgical cricothyrotomy in emergency and complicated airway management]

Objective:To explore the feasibility of intercricothyrotomy in emergency airway management. Method:Characteristics of 27 cases underwent surgical cricothyrotomy were analyzed. Result:The main causes of emergency were severe trauma of head and neck, larynx stenosis, interspaces infection of the floor of the mouth and submaxillary space, etc; all the patients were divided into 2 groups : surgical cricothyrotomy as the first choice (group A,16/27) and surgical cricothyrotomy after conventional tracheotomy (group B,11/27); The average time of opening airway for group A was much shorter than group B ［(58.12±24.41)s, (739.09±245.29)s,respectively, P<0.01)］; Bleeding in group A (14 cases) was much less than group B (13 cases) ［(2.36±1.16)ml, (4.65±4.31)ml,respectively, P<0.01］; Except 1 cases died from primary disease, 4 cases with laryngeal stenosis underwent laryngeal dilation with T type expansion tube and 2 cases of bilateral recurrent laryngeal nerve palsy, the average time with tracheal tube of the remaining 20 patients was (12.35±7.29)d, no postoperative complications such as larynx or tracheal stenosis were found. All of them were successfully extubation. Conclusion:Surgical cricothyrotomy procedure is fast and safe with simple and convenient that can be used as the preferred method of rapid airway opening when a critical respiratory tract was difficult to manage.

Incidence, prevalence, and mortality of Adamantiades-Behçet's disease in Korea: a nationwide, population-based study (2006-2015)

BACKGROUND

The epidemiology of Adamantiades-Behçet's disease varies among ethnic populations worldwide. Trends in the incidence of Adamantiades-Behçet's disease have not been investigated based on the Korean National Health Insurance database.

OBJECTIVES

This study investigated the incidence and mortality of Adamantiades-Behçet's disease by age using nationwide population data in Korea.

METHODS

A nationwide population-based cohort study was performed using the Korean National Health Insurance Claims Database from 2006 to 2015. The incidence of Adamantiades-Behçet's disease was calculated by age, sex, calendar year and habitat. And comorbid metabolic diseases were also analysed in patients with Adamantiades-Behçet's disease.

RESULTS

The annual incidence of Adamantiades-Behçet's disease per 100 000 person-years was 3.976 (2.587 for males and 5.373 for females) from 2006 to 2015. The incidence of Adamantiades-Behçet's disease peaked among people in their 40s (6.561 per 100 000 person-years). Incidence was significantly higher in subjects with comorbid metabolic conditions, such as diabetes mellitus, hypertension and dyslipidemia. The mortality rate per 1000 person-years increased with age in patients with Adamantiades-Behçet's disease.

CONCLUSIONS

This study showed the incidence, prevalence and mortality of Adamantiades-Behçet's disease. Metabolic conditions increased the risk of Adamantiades-Behçet's disease among Koreans.

[Drug resistance and dissemination of New Delhi metallo-β-lactamase 1 positive bacteria in a patient]

Objective: The aim of this work was to report the surveillance and dissemination of NDM-1 positive bacteria in a patient and ward environment. Methods: In 2010, during the therapy for a 51 years old patient, clinical and environmental samples were collected for carbapenem resistant bacterial culture, according to the clinical microbiological examination. Strains identification and antibiotic susceptibility were tested by VITEK Compact 2 system and E-test. The bla(NDM-1) was detected by PCR and analyzed by sequencing. Plasmids containing bla(NDM-1) were submitted to PFGE-S1 and Southern hybridization. Results: During hospitalization from October 1st to November 4th, nine strains were isolated from blood, sputum, urine, fecal, and ward ground samples. The Klebsiella oxytoca, Raoultella planticola, and Acinetobacter baumannii were isolated from blood sample. The Klebsiella pneumonia and Acinetobacter baumannii were isolated from sputum sample. An Acinetobacter lwoffii was isolated from urine sample. An Escherichia coli was isolated from fecal sample. And the Acinetobacter lwoffii and Acinetobacter spp. were isolated from ward ground. Four strains were NDM-1 positive, which were Raoultella planticola (RpNDM1) isolated from blood, Escherichia coli (EcNDM1) isolated from fecal, Acinetobacter lwoffii (AlDNM1) and Acinetobacter spp. (AsNDM1) isolated from ward ground. Four NDM-1 positive strains were resistant to Piperacillin, Piperacillin tazobactam, Cefepime, Ceftriaxone, Ceftazidime, Imipenem, Meropenem, and Ertapenem. Southern hybridization revealed that bla(NDM-1) were all located on plasmids in the four positive strains. Conclusion:bla(NDM-1) can transfer rapidly among different species, resulting in difficult to control and prevent. While isolating patient who is carrying NDM-1 positive strains, more attention should be paid to the disposal of patient's excreta, especially stool, should be paid more attention.

[Study on the classification of dominant pathogens related to febrile respiratory syndrome, based on the method of Bayes discriminant analysis]

Objective: To understand the dominant pathogens of febrile respiratory syndrome (FRS) patients in Gansu province and to establish the Bayes discriminant function in order to identify the patients infected with the dominant pathogens. Methods: FRS patients were collected in various sentinel hospitals of Gansu province from 2009 to 2015 and the dominant pathogens were determined by describing the composition of pathogenic profile. Significant clinical variables were selected by stepwise discriminant analysis to establish the Bayes discriminant function. Results: In the detection of pathogens for FRS, both influenza virus and rhinovirus showed higher positive rates than those caused by other viruses (13.79%, 8.63%), that accounting for 54.38%, 13.73% of total viral positive patients. Most frequently detected bacteria would include Streptococcus pneumoniae, and haemophilus influenza (44.41%, 18.07%) that accounting for 66.21% and 24.55% among the bacterial positive patients. The original-validated rate of discriminant function, established by 11 clinical variables, was 73.1%, with the cross-validated rate as 70.6%. Conclusion: Influenza virus, Rhinovirus, Streptococcus pneumoniae and Haemophilus influenzae were the dominant pathogens of FRS in Gansu province. Results from the Bayes discriminant analysis showed both higher accuracy in the classification of dominant pathogens, and applicative value for FRS.

Atopic dermatitis is inversely associated with hepatitis B antigen positivity: a population-based cohort study

BACKGROUND

No clear association between hepatitis B virus (HBV) infection and atopic dermatitis (AD) has been established. Some studies have reported that subjects with HBV had an increased risk of atopy; other studies reported an inverse association between HBV seropositivity and allergic diseases.

OBJECTIVE

We evaluated the association between AD and hepatitis B antigen (HBsAg) positivity using Korean National Health and Nutrition Examination Survey data.

METHODS

In total, 14 776 participants aged >19 years were included in the analysis. Multiple logistic regression analyses were used to evaluate the odds ratio of HBsAg positivity in association with AD and asthma.

RESULTS

The prevalence of HBsAg positivity was lower in individuals with AD than in those without AD (mean [SE], 0.7% [0.4] vs. 3.7% [0.2]; P < 0.001). However, HBsAg positivity was not significantly associated with asthma (3.7% [0.2] vs. 2.8% [0.8]; P < 0.001). HBsAg positivity decreased the risk of AD significantly (OR = 0.223; 95% CI = 0.069-0.72).

CONCLUSIONS

This study demonstrates an inverse association between AD and HBsAg positivity using a nationwide, population-based, cross-sectional health examination and survey.

A PC-based laparoscopic surgery skills training and assessment system

The purpose of this study is to build a cost-effective and easy-to-popularize laparoscopic training system based on improving traditional training box. The system has the capability of objective skills assessment and the function of automatic recording of training process and results, as well as 3-dimensional coordinate tracking of instruments. The results of pilot experiment in laparoscopic-assisted grip skill assessment had been shown the system can assess the different grip ability level between the senior surgeons and junior residents. Regarding to the evaluation of training effectiveness, five subjects without laparoscopic surgery experiences were asked to perform grip training for five days to observe their training curves. According to the experimental results, the total time taken for subject 1 to subject 5 are improved by 54.9%, 52.0%, 60.6%, 23.3%, and 63.5% separately.

Low CHD5 expression activates the DNA damage response and predicts poor outcome in patients undergoing adjuvant therapy for resected pancreatic cancer

The DNA damage response (DDR) promotes genome integrity and serves as a cancer barrier in precancerous lesions but paradoxically may promote cancer survival. Genes that activate the DDR when dysregulated could function as useful biomarkers for outcome in cancer patients. Using a siRNA screen in human pancreatic cancer cells, we identified the CHD5 tumor suppressor as a gene, which, when silenced, activates the DDR. We evaluated the relationship of CHD5 expression with DDR activation in human pancreatic cancer cells and the association of CHD5 expression in 80 patients with resected pancreatic adenocarcinoma (PAC) by immunohistochemical analysis with clinical outcome. CHD5 depletion and low CHD5 expression in human pancreatic cancer cells lead to increased H2AX-Ser139 and CHK2-Thr68 phosphorylation and accumulation into nuclear foci. On Kaplan-Meier log-rank survival analysis, patients with low CHD5 expression had a median recurrence-free survival (RFS) of 5.3 vs 15.4 months for patients with high CHD5 expression (P=0.03). In 59 patients receiving adjuvant chemotherapy, low CHD5 expression was associated with decreased RFS (4.5 vs 16.3 months; P=0.001) and overall survival (OS) (7.2 vs 21.6 months; P=0.003). On multivariate Cox regression analysis, low CHD5 expression remained associated with worse OS (HR: 3.187 (95% CI: 1.49-6.81); P=0.003) in patients undergoing adjuvant chemotherapy. Thus, low CHD5 expression activates the DDR and predicts for worse OS in patients with resected PAC receiving adjuvant chemotherapy. Our findings support a model in which dysregulated expression of tumor suppressor genes that induce DDR activation can be utilized as biomarkers for poor outcome.

Genomic selection of seed weight based on low-density SCAR markers in soybean

With the development of molecular marker technology, crop breeding has been accelerated by marker-assisted selection for the improvement of quantitative traits. However, due to the traits' polygenic nature, traditional marker-assisted selection methods are ill-suited for identification of quantitative trait loci. Genomic selection (GS) was introduced into crop breeding to achieve more accurate predictions by considering all genes or markers simultaneously. We used dozens of sequence-characterized amplified region (SCAR) markers for genotyping soybean varieties, and we identified markers associated with hundred-seed weight. The best linear unbiased predictor and Bayesian liner regression methods were used to construct GS models to predict the hundred-seed weight trait based upon genotype information for trait selection. Both GS models showed good prediction performance in soybean, as the correlation coefficient between genomic estimated breeding values and true breeding values was as high as 0.904. This indicated that GS was performed effectively based on dozens of SCAR markers in soybean; these markers were of low density but easily detectable. Therefore, the combination of GS modeling and highly effective molecular marker technology involving SCAR markers can facilitate genetic breeding in soybean. This approach may also be suitable for genetic selection in other crops, such as wheat, maize, and rice.

Neuronal-derived nitric oxide modulates the activity of mouse detrusor smooth muscle

AIMS

We investigated the roles of neuronal-derived nitric oxide (NO) in the modulation of spontaneous activity of mouse detrusor smooth muscle.

METHODS

Detrusor smooth muscle strips were isolated from nNOS gene knock-out (nNOS(-/-) ) mice and their wild type siblings (nNOS(+/+) ). The properties of smooth muscle cells were assessed using intracellular electrophysiology and Ca(2+) imaging by laser-scanning confocal microscopy. The effects of an nNOS inhibitor, 7-nitro indazole (7-NI) on electrically evoked contractility were assessed using nNOS(+/+) mouse detrusor strips.

RESULTS

In spontaneously active cells, the frequency of spontaneous action potentials (sAPs) and whole cell Ca(2+) flashes in nNOS(-/-) preparations was lower than that in the nNOS(+/+) preparations. The frequency of sAPs was enhanced by a nitric oxide donor, diethylamine NONOate sodium salt (NONOate; 100 µM), both when used alone and when the cGMP pathway was blocked by 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ, 10 µM). 7-NI (100 µM) significantly suppressed the electrically evoked contraction of mouse detrusor strips.

CONCLUSIONS

We suggest that neuronal-derived NO facilitates the generation of spontaneous activity via a cGMP-independent pathway, and consequently enhances the evoked contraction of detrusor. Dysregulation of nNOS containing nerves may underlie bladder pathologies.

Regional patterns of soil organic carbon stocks in China

Soil organic carbon (SOC) is of great importance in the global carbon cycle. Distribution patterns of SOC in various regions of China constitute a nation-wide baseline for studies on soil carbon changes. This paper presents an integrated and multi-level study on SOC stock patterns of China, and presents baseline SOC stock estimates by great administrative regions, river watersheds, soil type regions and ecosystem. The assignment is done by means of a recently completed 1: 1,000,000 scale soil database of China, which is the most detailed and reliable one in China at the present time. SOC densities of 7292 soil profiles collected across China in the middle of the 1980s were calculated and then linked to corresponding polygons in a digital soil map, resulting in a SOC Density Map of China on a 1: 1,000,000 scale, and a 1 km x 1 km grid map. Corresponding maps of administrative regions, river watersheds, soil types (ST), and ecosystems in China were also prepared with an identical resolution and coordinate control points, allowing GIS analyses. Results show that soils in China cover an area of 9.281 x 10(6)km(2) in total, with a total SOC stock of 89.14 Pg (1 Pg=10(15)g) and a mean SOC density of 96.0 t C/ha. Confidence limits of the SOC stock and density in China are estimated as [89.23 Pg, 89.08 Pg] and [96.143 t C/ha, 95.981 t C/ha] at 95% probability, respectively. The largest total SOC stock (23.60 Pg) is found in South-west China while the highest mean SOC density (181.9 t C/ha) is found in north-east China. The total SOC stock and the mean SOC density in the Yangtze river watershed are 21.05 Pg and 120.0 t C/ha, respectively, while the corresponding figures in the Yellow river watershed are 8.46 Pg and 104.3 t C/ha, respectively. The highest total SOC stocks are found in Inceptisols (34.39 Pg) with SOC density of 102.8 t C/ha. The lowest and highest mean SOC densities are found on Entisols (28.1 t C/ha), and on Histosols (994.728.1 t C/ha), respectively. Finally, the total SOC stock in shrub and forest ecosystem classes are 25.55 and 21.50 Pg, respectively; the highest mean SOC density (209.9 t C/ha) was recorded in the wetland ecosystem class and the lowest (29.0 t C/ha) in the desert ecosystem class. Among five forest ecosystem types, Evergreen conifer forest stores the highest SOC stock (6.81 Pg), and Deciduous conifer forest shows the highest SOC density (225.9 t C/ha). Figures of SOC stocks stratified by Administrative regions, river watersheds, soil types and ecosystem types presented in the study may constitute national-wide baseline for studies of SOC stock changes in various regions in the future.

Investigation of the corticotropin-releasing hormone-proopiomelanocortin axis in various skin tumours

BACKGROUND

Various types of external stress cause the skin and central neuroendocrine system to express corticotropin-releasing hormone (CRH)-proopiomelanocortin (POMC) axis-related hormones. However, the precise role of the CRH-POMC axis-related hormones in various skin tumours is unclear.

OBJECTIVES

This study examined expression patterns of the CRH-POMC axis-related hormones in skin tumours.

METHODS

The production of CRH, adrenocorticotropic hormone (ACTH) and alpha-melanocyte-stimulating hormone (alpha-MSH) in various tumour cell lines including HaCaT and primary keratinocytes was examined using an enzyme-linked immunosorbent assay. Immunohistochemical analysis of the skin tumours was also performed.

RESULTS

CRH, ACTH and alpha-MSH were strongly expressed in malignant skin tumour cell lines such as G-361 and DX-3 (both malignant melanoma, MM). However, normal and haematological malignancy cell lines did not express the CRH-POMC axis-related hormones. Immunohistochemical analysis of the skin tumours showed that MM (80%), squamous cell carcinoma (SCC, 70%) and basal cell carcinoma (BCC, 10%) had strong immunoreactivity (++/+++) for CRH. Strong ACTH and alpha-MSH expression was observed in MM (70% and 50%, respectively), SCC (80% and 60%, respectively) and BCC (70% and 50%, respectively).

CONCLUSIONS

We report that an increase in the level of the CRH-POMC axis-related hormones is associated with malignant skin tumours such as MM. These results highlight the importance of the CRH-POMC axis-related hormones in the malignant tendency of skin tumours.

Redistribution of androgen receptors in acquired hormone-refractory prostate cancer cells

The dynamic translocation of androgen receptors (ARs) in prostate cancer cells after hormone conversion was studied. The prostate cancer cell line LNCaP was converted into androgen-independent sublines after long-term treatment with 5alpha-reductase inhibitor and steroid-depleted medium. Immunohistochemical, immunofluorescent staining and laser scanning microscopy were used to observe the redistribution and serial translocation of ARs in these tumor cells. The androgen-independent tumor cells (LNCaP/Fin and LNCaP/HR) grew slower than native cells with fibroblastic-like characteristics. On immunohistochemical and immunofluorescent double staining, translocation and exocytosis of ARs were noted in androgen- independent tumor cells much more markedly than in native cells. Furthermore, laser-scanning microscopy revealed serial image changes of AR vesicle shifting and exocytosis in androgen-converted tumor cells. Translocation and exocytosis processes were observed in androgen-independent prostate cancer cells. ARs lose partly normal cellular biologic role during hormone manipulation.

Pilot-scale studies on biological treatment of hypersaline wastewater at low temperature

In order to investigate the feasibility of biological treatment of hypersaline wastewater produced from toilet flushing with seawater at low temperature, pilot-scale studies were established with plug-flow activated sludge process at low temperature (5-9 degrees C) based on bench-scale experiments. The critical salinity concentration of 30 g/L, which resulted from the cooperation results of the non-halophilic bacteria and the halophilic bacteria, was drawn in bench-scale experiments. Pilot-scale studies showed that high COD removal efficiency, higher than 80%, was obtained at low temperature when 30 percent seawater was introduced. The salinity improved the settleability of activated sludge, and average sludge value dropped down from 38% to 22.5% after adding seawater. Seawater salinity had a strong negative effect on notronomonas and nitrobacter growth, but much more on the nitrobacter. The nitrification action was mainly accomplished by nitrosomonas. Bench-scale experiments using two SBRs were carried out for further investigation under different conditions of salinities, ammonia loadings and temperatures. Biological nitrogen removal via nitrite pathway from wastewater containing 30 percent seawater was achieved, but the ammonia removal efficiency was strongly related not only to the influent ammonia loading at different salinities but also to temperature. When the ratio of seawater to wastewater was 30 percent, and the ammonia loading was below the critical value of 0.15 kgNH4+-N/(kgMLSS.d), the ammonia removal efficiency via nitrite pathway was above 90%. The critical level of ammonia loading was 0.15, 0.08 and 0.03 kgNH4+-N/(kgMLSS.d) respectively at the different temperature 30 degrees C, 25 degrees C and 20 degrees C when the influent ammonia concentration was 60-80 mg/L and pH was 7.5-8.0.

Aggressive angiomyxoma of the scrotum

Aggressive angiomyxoma is a rare and nonmetastasizing soft tissue tumor of the pelvis and perineum and occurs almost exclusively in adult females. It infiltrates locally and has a high risk of local recurrence. Recommended treatment of the symptomatic patient is wide excision with tumor-free margins and close postoperative monitoring. Herein, a case of aggressive angiomyxoma in an adult male is described, which arose in the scrotum over 12 months. The tumor showed an intermediate signal on T1-weighted MRI images. Contrast-enhanced T1-weighted images showed good enhancement. Wide excision of the tumor was performed. The surgical specimen measured 7 x 5 x 5 cm in size and weighed 80 g. The tumor's surface was smooth and had a gelatinous cut surface. Grossly, it was encapsulated with a pleura-like membrane and had a finger-like projection. Microscopically, sections showed many walled vessels of various sizes, collagen fibrils, a loose myxoid background. and spindle stroma cells. MRI and CT showed the angiomatous and myxomatous nature of the tumor wall. To the authors' knowledge, this is the first report to describe MRI findings in scrotal angiomyxoma.

The expression of neuropeptides in hyperplastic and malignant prostate tissue and its possible clinical implications

PURPOSE

We characterized the incidence and pattern of distribution of neuroendocrine differentiated tumor cells in prostatic hyperplastic and carcinomatous tissue, correlated neuroendocrine differentiation with prostate specific antigen (PSA) and assessed whether neuroendocrine cells have value as an independent indicator of poor prognosis in patients with prostate carcinoma.

MATERIALS AND METHODS

We immunohistochemically evaluated hyperplastic and carcinomatous prostate specimens for chromogranin A, neuron specific enolase and serotonin expressing tumor cells. The expression of various markers in cells was analyzed and correlated with tumor DNA ploidy, disease grade and stage, PSA and clinical course in patients with prostate cancer.

RESULTS

Enrolled in our study were 31 patients with hyperplastic prostate tissue and 30 with prostatic carcinoma. Followup in cancer cases was 1 to 9 years (mean 3.7). During followup 9 patients (30%) died of cancer. We noted DNA content aneuploidy in 5 cases (16.7%) of prostate carcinoma. Chromogranin A, neuron specific enolase and serotonin were expressed in 80%, 43% and 77% of cases of prostate carcinoma and in 29%, 10% and 36% of hyperplastic tissue, respectively. Larger prostates had no higher content of various neuroendocrine cells than smaller prostates. There was higher expression of neuropeptides in carcinomatous than in hyperplastic tissue. Of the 3 peptides chromogranin A was significantly related to all parameters, including Gleason score, tumor stage, PSA and patient survival. In addition to PSA, neuron specific enolase was also closely associated with other clinicopathological parameters. Serotonin was significantly related to patient survival only but we noted no correlation with Gleason score, tumor stage or PSA. In regard to factors predictive of patient prognosis expression of the 3 neuropeptides in tumor cells, Gleason score, tumor stage and PSA were closely related to patient survival in this study

CONCLUSIONS

The growth of hyperplastic prostate tissue is related to neuroendocrine cell activity. The chromogranin A marker has the highest expression in prostate cancer. Neuroendocrine cells may represent an independent indicator of poor prognosis in patients with prostate carcinoma.

Detection of chromosomal alterations in bladder cancer by comparative genomic hybridization

OBJECTIVES

To characterize which genomic alterations occur in bladder cancers of different grades and stages, and to evaluate the prognostic implication of chromosomal imbalances. Materials and methods Twelve transitional cell carcinoma cell lines were used to study chromosomal aberrations, using comparative genomic hybridization to examine metaphase cells.

RESULTS

There was a mean of 6.0 aberrations per tumour with 4.9 gains and 1.08 deletions per tumour cell line. The mean number of aberrations was the same in grade 2 and 3 tumours. High-stage (>/= T2) carcinomas had markedly more genomic gains than had low-stage (T1) tumours, with 7.2 gains and 1.3 deletions per >/= T2 tumour, and 2.7 gains and 0.8 deletions per T1 tumour, although the difference was not statistically significant. The most frequent changes were gains of chromosome 1 (seven), 9 and 16 (six), and losses of chromosomes 14 (three), 21 and Y (two). The changes 1p+, 3p+, 9q+, 14p-, 16q+ and Yp- were significantly more frequent in low-grade tumours, with 1p+, 3p+ and Yq- the most frequent in stage T1 tumours, and 16p+, 9q+ and 13q- the most frequent in stage >/= T2 tumours. Conclusion These findings indicate several genomic regions in chromosomes 1, 9, 14 and 16 that may carry genes for the development and progression of bladder cancers.

Growth pattern of renal angiomyolipoma on computed tomography: report of two cases

The incidence of renal angiomyolipoma is increased in patients with tuberous sclerosis. Renal angiomyolipomas frequently exhibit both intratumoral and subcapsular or perirenal hemorrhage when they grow into the extrarenal space. Evidence of serial morphologic change is crucial to decision-making for surgical exploration in patients with growing renal angiomyolipomas. We report two cases of angiomyolipoma of the kidney with expansion of an angiomyolipoma into the subcapsular region. Neither patient had tuberous sclerosis and both developed bleeding when the mushroom-shaped tumor reached the extrarenal space. These cases suggest that expansion of the tumor into the subcapsular region is indicative of impending rupture of a renal angiomyolipoma.

A functional comparison of BRCA1 C-terminal domains in transcription activation and chromatin remodeling

The BRCA1 C-terminal (BRCT) domain is present in a number of proteins that are involved in various aspects of chromosomal events. The BRCT domain of BRCA1 is important for its function in DNA repair and transcriptional activation. When tethered to chromosomal DNA, this region of BRCA1 is capable of inducing changes in chromatin structure. Despite the sequence homology and functional proximity shared by the BRCT-containing proteins, it is not clear whether different BRCT domains confer a common biochemical activity. Much less is known about the functional significance of the characteristic amino acid residues in the BRCT motif. Here, we show that chromatin remodeling and transcription activation is not a common feature of BRCT domains. However, the BRCT domain of the multi-functional repressor-activator protein 1 (RAP1) can activate transcription and remodel chromatin in a manner similar to that shown for the BRCA1 BRCT domain. Most of the conserved amino acid residues in the second BRCA1 BRCT domain are essential for its function in transcriptional activation. In contrast, mutations of many analogous amino acid residues in the RAP1 BRCT domain greatly elevate the transcriptional activity. These data indicate that the conserved residues in these two BRCT domains may play different roles in transcriptional activation.

Expression of CD34 and Myf5 defines the majority of quiescent adult skeletal muscle satellite cells

Skeletal muscle is one of a several adult post-mitotic tissues that retain the capacity to regenerate. This relies on a population of quiescent precursors, termed satellite cells. Here we describe two novel markers of quiescent satellite cells: CD34, an established marker of hematopoietic stem cells, and Myf5, the earliest marker of myogenic commitment. CD34(+ve) myoblasts can be detected in proliferating C2C12 cultures. In differentiating cultures, CD34(+ve) cells do not fuse into myotubes, nor express MyoD. Using isolated myofibers as a model of synchronous precursor cell activation, we show that quiescent satellite cells express CD34. An early feature of their activation is alternate splicing followed by complete transcriptional shutdown of CD34. This data implicates CD34 in the maintenance of satellite cell quiescence. In heterozygous Myf5(nlacZ/+) mice, all CD34(+ve) satellite cells also express beta-galactosidase, a marker of activation of Myf5, showing that quiescent satellite cells are committed to myogenesis. All such cells are positive for the accepted satellite cell marker, M-cadherin. We also show that satellite cells can be identified on isolated myofibers of the myosin light chain 3F-nlacZ-2E mouse as those that do not express the transgene. The numbers of satellite cells detected in this way are significantly greater than those identified by the other three markers. We conclude that the expression of CD34, Myf5, and M-cadherin defines quiescent, committed precursors and speculate that the CD34(-ve), Myf5(-ve) minority may be involved in maintaining the lineage-committed majority.

Impact of the '2 week wait' directive for suspected cancer on service provision in a symptomatic breast clinic

BACKGROUND

The '2 week wait' directive (Health Service Circular (HSC) 1998/242) guaranteeing that 'everyone with suspected breast cancer will be able to see a specialist within two weeks of their general practitioner (GP) deciding they need to be seen urgently' is a unique audited approach to access for the British National Health Service, the effects of which have been assessed in a non-academic symptomatic breast clinic.

METHODS

New GP referrals (n = 607) were reviewed prospectively in two comparable 3-month intervals, beginning 1 April 1998 and 1 April 1999, to determine the probability of a breast cancer diagnosis from the referral letter and the effects of the directive on waiting times for appointments and utilization of clinics.

RESULTS

The urgency of referral was not specified in 53 per cent of GP referrals. For the 'urgent' cases (25 per cent of all new referrals) the probability of a final diagnosis of breast cancer was 0.19. The breast specialists prospectively achieved a rate of 0.26 from 99 per cent of the same referral letters. 'Urgent' referrals did not wait significantly longer in 1999 (median 9 versus 10 days) but waiting times for new appointments overall increased (13 versus 16 days; P < 0.01), and this was greatest for 'routine' [14] versus 21 days; P < 0.001). These changes were caused by an increase in the number of clinic appointments, due to significant increases in median number of visits to diagnosis or discharge and clinic non-attendance in 1999, resulting in overbooking. Telephonic communications were associated with faster median access times (fax 8 days; telephone 2 days), relative to mailed [19] days) (P < 0.01).

CONCLUSION

Breast specialists were better overall at assessing the probability of a breast cancer diagnosis. The waiting time for 'urgent' appointments was unchanged following HSC 1998/242, but there was an increased wait for other patients, especially those assessed as having a lower probability of cancer.

Conjugation of maturation-related wheat-germ-lectin-binding proteins to caput epididymal sperm in co-cultures with corpus epididymal epithelial cells of BALB/c mouse

In BALB/c mice, two maturation-related wheat-germ-binding glycoproteins (GP-49 and GP-83) are synthesized and secreted by corpus and cauda epididymis. A co-culture technique was used to investigate these glycoproteins in principal cells of corpus epididymis and the conjugation of these molecules on caput sperm. The principal cells were recovered from corpus epididymides of 4-week-old mice and cultured in RPMI 1640 medium supplemented with 10% fetal calf serum. After culturing for 3-4 days, most cells revealed epithelial cell-specific keratins in immunofluorescent localization with monoclonal antibody. By electron microscopy, a prominent nucleolus with well-extended euchromatin was revealed in the nucleus and the cytoplasm contained multivesicular bodies, and a well-developed Golgi apparatus with endoplasmic reticulum. By SDS-PAGE, GP-83 and GP-49 were revealed in the cell extracts and cell culture supernatants after incubation with 35S-methionine. Radiolabeled binding sites were also found on the surface of caput sperm co-cultured with the principal cells for 4 h in the presence of 35S-methionine. WGA-binding glycoproteins may be synthesized and secreted by the principal cells of corpus epididymis and conjugated to caput sperm during the epididymal transit.

Successful treatment of azoospermia secondary to ejaculatory duct cyst

Ejaculatory duct obstruction is considered a rare cause of infertility. Two cases are reported of an ejaculatory duct cyst with azoospermia preoperatively diagnosed by transrectal ultrasonography. The diagnosis of ejaculatory duct obstruction in one patient was confirmed by vasography with a combined iodinated contrast medium and methylene blue solution for radiological and direct visualization. Transrectal puncture and contrast filling of the cyst under the transrectal ultrasonographic guidance diagnosed the other patient. On the basis of these findings transurethral unroofing of the cyst was performed successfully. Transrectal ultrasonography facilitates evaluation and treatment of azoospermia caused by ejaculatory duct obstruction and may minimize the need for more invasive studies in such cases.

Giant hydronephrosis of a duplex system associated with ureteral ectopia: a cause of retrograde ejaculation

Retrograde ejaculation is an extremely rare complication of the ectopic ureter or ectopic ureterocele. In the literature, only two cases have been reported worldwide. In this article the authors describe a patient who has a completely duplicated collecting system with massive dilatation of the upper pole system, which has manifested as a huge abdominal and retroperitoneal mass, complicated by retrograde ejaculation.

Identification of maturation-related wheat-germ lectin-binding proteins in the culture of human corpus epididymal epithelial cells

This study is designed to investigate the synthesis of maturation-related wheat germ agglutinin (WGA) binding glycoproteins in the human corpus epididymal epithelial cells by in vitro culture. Epithelial cells were isolated from the corpus of human epididymides and cultured with RPMI 1640 medium supplemented with 10% fetal calf serum in type IV collagen-coated dishes at 37 degrees C. The epithelial nature, presence of fibroblasts, WGA-binding sites, and existence of GP-83 were determined by an indirect immunocytochemical and histochemical staining technique. Proteins in the cultured cells were analyzed by SDS-PAGE and autoradiography. After culturing for 10 days, the cells were shown to be positive with epithelial cell-specific keratins but devoid of fibroblasts. WGA-binding granules and positive binding sites of GP-83 were also detected in the cytoplasm. Immunoblots of cell extracts probed with the anti-GP-83 antibody from seminal fluid revealed the sperm maturation-related glycoprotein GP-83. The results indicate that WGA-binding proteins may be synthesized by the corpus epididymal epithelial cells of human and GP-83 may play an important role in sperm maturation. This culture model may be suitable for the investigation on the biosynthesis and physiology of human epididymal principal cells in vitro.

Verapamil modulation of multidrug resistance in renal cell carcinoma

BACKGROUND AND PURPOSE

Renal cell carcinoma (RCC) is well known for its chemoresistance. The membranous p-glycoprotein (gp-170) is believed to be highly correlated with multidrug resistance (MDR) of cancer cells with energy-dependent pumping efflux of anticancer drugs. Verapamil, a calcium antagonist, inhibits the efflux function of gp-170 and cytoskeletal transportation. The aim of this study was to determine the effect of verapamil on gp-170 expression and intracellular drug accumulation in RCC tumor cells and the modulation of cytotoxicity of various chemotherapeutic drugs on native RCC cell lines and acquired MDR sublines by verapamil.

METHODS

Using cultured cell lines of RCC and their MDR sublines as target cells, the effect of verapamil on gp-170 expression was analyzed by immunofluorescence flow cytometry. The influence of verapamil on intracellular drug accumulation in RCC tumor cells was measured by autofluorescence flow cytometry. The modulation of verapamil on cytotoxicity of various chemotherapeutic drugs on native RCC cell lines and acquired MDR sublines was analyzed by the methyl tetrazolium method.

RESULTS

From flow cytometric measurement, the expression of gp-170 was significantly decreased in A704 and Caki-1 tumor cells after verapamil treatment. The uptake of adriamycin and maintenance of intracellular drugs were also significantly increased following verapamil treatment in RCC8701 tumor cells. These effects were sustained for as long as 8 hours after verapamil withdrawal. The cytotoxicity of adriamycin and epirubicin on RCC8701 and its MDR subline tumor cells was markedly intensified by verapamil. The verapamil modulation of cytotoxicity was in an immediate-reaction pattern and was dose-dependent, with synergistic effects. Long-term treatment was more effective than short-term treatment in RCC MDR sublines. The cytotoxicity of vinca alkaloid (vinblastine) and alkylators (carboplatin) was also enhanced by verapamil.

CONCLUSIONS

These results suggest that verapamil plays an important role in the circumvention of native and acquired chemoresistance of RRC because it suppresses membranous gp-170 expression and cytoplasmic drug transportation.

Establishment and characterization of renal cell carcinoma cell lines with multidrug resistance

Many of the discoveries of multidrug resistance (MDR) have resulted from studies using drug-resistant cultured tumor cell lines as experimental models. To date, there has been no report on the detailed characterization of such a cell line from renal cell carcinoma (RCC). By long-term exposure of an established RCC (RCC8701) to increasing concentrations of adriamycin, we established a series of subcultures that were considerably more resistant to the cytotoxic effect of this drug. Biological morphology and cell cycles were analyzed by morphometry and flow cytometry. The chemoresistance index of cells were measured by methyl tetrazolium assay. For evaluation of the expression of MDR-related protein (MRP), mdr-1, glutathione transferase (GST-pi), and topoisomerase II mRNAs, the reverse transcription-polymerase chain reaction was used. Membranous expression of mdr-1-related p-glycoprotein was analyzed by immunofluorescence cytometry. The intracellular content of both glutathione (GSH) and glucose-6-phosphate dehydrogenase (G-6-PDH) were measured using a capillary electrophoresis method. Compared with parent cells, the resistant sublines had a slower growth rate and lower confluent density. They were smaller and mixed with giant cells in different sizes and with different numbers of nucleoli. Flow cytometric analyses showed that resistant cells had a greater percentage of cells in the G2/M phase. The resistant cells, RCC8701/ADR800, were 122 times more resistant to adriamycin and 238 times more resistant to epirubicin than the parent cells. The resistant cells also demonstrated cross-resistance to cisplatin and 5-fluorouracil. In addition to MRP, the contents of mRNA coding for mdr-1, GST-pi, and topoisomerase II in the MDR sublines were higher than in the native cell line. A higher content of cytoplasmic GSH and G-6-PDH were found in the resistant cells; however, the expression of the MDR-related membranous glycoprotein, p-glycoprotein, was not raised. The adriamycin-induced MDR sublines may be used as an experimental system for the search of a means to overcome drug resistance and elucidate possible mechanisms of acquired MDR involved in human renal cancer.

Patterns of repair of dystrophic mouse muscle: studies on isolated fibers

Repair of damaged skeletal muscle fibers by muscle precursor cells (MPC) is central to the regeneration that occurs after injury or disease of muscle and is vital to the success of myoblast transplantation to treat inherited myopathies. However, we lack a detailed knowledge of the mechanisms of this muscle repair. Here, we have used a novel combination of techniques to study this process, marking MPC with nuclear-localizing LacZ and tracing their contribution to regeneration of muscle fibers after grafting into preirradiated muscle of the mdx nu/nu mouse. In this model system, there is muscle degeneration, but little or no regeneration from endogenous MPC. Incorporation of donor MPC into injected muscles was analyzed by preparing single viable muscle fibers at various times after cell implantation. Fibers were either stained immediately for beta-gal, or cultured to allow their associated satellite cells to migrate from the fiber and then stained for beta-gal. Marked myonuclei were located in discrete segments of host muscle fibers and were not incorporated preferentially at the ends of the fibers. All branches on host fibers were also found to be composed of myonuclei carrying the beta-gal marker. There was no significant movement of donor myonuclei within myofibers for up to 7 weeks after MPC implantation. Although donor-derived dystrophin was usually located coincidentally with donor myonuclei, in some fibers, the dystrophin protein had spread further along the mosaic myofibers than had the myonuclei of donor origin. In addition to repairing segments of the host fiber, the implanted MPC also gave rise to satellite cells, which may contribute to future muscle repair.

Flow-cytometric measurement of cellular changes in urine: a simple and rapid method for perioperatively monitoring patients after kidney transplantation

OBJECTIVE

In renal transplant patients having graft dysfunction, it is usually difficult to obtain the accurate diagnosis, such as acute rejection, acute tubular necrosis, infection, or cyclosporin nephrotoxicity. An accurate diagnosis can provide the proper treatment of these patients, thereby lessening the chance of kidney loss.

METHODS

A total of 42 patients were enrolled. By using the flow-cytometric technique, the white cell populations of urine in these patients were analyzed and linked to their clinical course. All patients underwent sonography-guided biopsy of the transplanted kidney with a definitive diagnosis.

RESULTS

When 10% lymphocytes and 15% granulocytes in urine were set as the cutoff point of a normal ratio threshold, the flow-cytometric analysis presented the highest sensitivity and the highest negative predictive rate for acute tubular necrosis. However, a lower sensitivity and positive predictive rate was found in acute rejection cases.

CONCLUSIONS

Our results suggest that flow-cytometric analysis of the urinary cell population can be used as an adjunct in patient follow-up after kidney transplantation.

Cocktail modulator mixtures for overcoming multidrug resistance in renal cell carcinoma

OBJECTIVES

To determine the effect of various modulators on intracellular drug accumulation in renal cell carcinoma (RCC) tumor cells and the modulation of cytotoxicity of various chemotherapeutic drugs on the native RCC cell line and acquired intrinsic multidrug resistance (MDR) sublines because MDR is a major obstacle to effective chemotherapy of RCC.

METHODS

The cytotoxicity of adriamycin to RCC 8701 and its MDR subline was analyzed. Fourteen MDR modulators, including calcium antagonists, protein kinase C inhibitor, glutathione transferase inhibitor, protein/peptide synthesis inhibitors, respiratory chain inhibitors, uncoupling reagent, adenosine triphosphate synthesis inhibitor, and ionophores, were examined for their MDR-reverse activity using the microplate tetrazolium test.

RESULTS

The intracellular adriamycin concentration significantly increased and reached maximum 4 hours after simultaneous treatment with calcium antagonists, tamoxifen, and oligomycin. The result demonstrated that verapamil, quinidine, tamoxifen, and oligomycin had an additive effect on the cytotoxicity of adriamycin and vinblastine against RCC8701 and RCC8701/ADR800 tumor cells. RCC8701/ADR800 tumor cells were more sensitive to modulator enhancement than native cells. The enhancement was related to the dosage and treatment duration of the modulators. Further trials on simultaneous additions to cocktail mixtures of the above four modulators showed no additive or synergistic effect on cytotoxicity against RCC8701/ADR800 tumor cells.

CONCLUSIONS

Calcium antagonists and tamoxifen and oligomycin can individually be an effective chemotherapy adjunct for overcoming the native drug resistance or acquired MDR in RCC. Combination regimens, however, need more study regarding timing of administration, dosage, and frequency of modulators.