Priority list of potential endocrine-disrupting chemicals in food chemical contaminants: a docking study and in vitro/epidemiological evidence integration

Diet is an important exposure route of endocrine-disrupting chemicals (EDCs), but many unfiltered potential EDCs remain in food. The in silico prediction of EDCs is a popular method for preliminary screening. Potential EDCs in food were screened using Endocrine Disruptome, an open-source platform for inverse docking, to predict the binding probabilities of 587 food chemical contaminants with 18 human nuclear hormone receptor (NHR) conformations. In total, 25 contaminants were bound to multiple NHRs such as oestrogen receptor α/β and androgen receptor. These 25 compounds mainly include pesticides and per- and polyfluoroalkyl substances (PFASs). The prediction results were validated with the in vitro data. The structural features and the crucial amino acid residues of the four NHRs were also validated based on previous literature. The findings indicate that the screening has good prediction efficiency. In addition, the epidemic evidence about endocrine interference of PFASs in food on children was further validated through this screening. This study provides preliminary screening results for EDCs in food and a priority list for in vitro and in vivo research.

[Seroprevalence of Toxoplasma gondii and Toxocara infections among pregnant women in Hangzhou City]

OBJECTIVE

To investigate the prevalence of Toxoplasma gondii and Toxocara infections among pregnant women in Hangzhou City, so as to provide baseline data for decreasing birth defects and improving the population quality.

METHODS

A total of 235 pregnant women receiving prenatal diagnosis at the First People's Hospital of Yuhang District during the period between February 2018 through December 2019 were recruited as the observation group, and 235 age-matched, non-pregnant healthy women at the same hospital during the same period served as the control group. The subjects'medical records were captured from the hospital management information system. Blood samples were collected from the observation and control groups and detected for the presence of IgG antibodies against T. gondii and Toxocara using an enzyme-linked immunosorbent assay (ELISA). The seroprevalence of the IgG antibodies against T. gondii and Toxocara was compared between the observation and control groups.

RESULTS

The subjects in the observation group had a mean age of 26.5 ± 4.3 years (range, 23 to 31 years), and gestational ages of 10 to 27 weeks, and the subjects in the control group had a mean age of 26.1 ± 5.7 years (range, 20 to 30 years). The seroprevalence rates of IgG antibodies against T. gondii (28.51% vs. 4.68%; χ² = 34.85, P < 0.01) and Toxocara (24.26% vs. 5.11%; χ² = 25.77, P < 0.01) were both significantly higher in the observation group than in the control group, and the seroprevalence of T. gondii and Toxocara co-infections was also significantly greater in the observation group than in the control group (13.19% vs. 2.13%; χ² = 17.49, P < 0.01).

CONCLUSIONS

The seroprevalence rates of T. gondii and Toxocara infections and their co-infections are all high among pregnant women in Hangzhou City. Screening of T. gondii and Toxocara infections is strongly recommended during pregnancy.

Low pretreatment PNI correlates with worse survival in patients with stage III/IV NSCLC who received chemotherapy

The aim of this study was to investigate the prognostic value of the prognostic nutritional index (PNI) on the long-term survival of non-small cell lung cancer (NSCLC) patients who received platinum-based chemotherapy. Data on nutritional parameters and clinicopathological characteristics [e.g., albumin, total protein, body mass index (BMI), eastern cooperative oncology group (ECOG) performance status, stage, pathology, treatment strategy] were analyzed and retrospectively correlated with overall survival (OS). The PNI was calculated based on the concentration of albumin and lymphocyte count [10 × albumin, (g/dl) + 0.005 × lymphocyte (count/mm3)]. A receiver operating characteristic curve (ROC) analysis was used to find the optimal cut-off value of PNI. Univariate and multivariate analyses were used to evaluate the prognostic value of PNI. A total of 186 patients met the inclusion criteria. The optimal cut-off value for PNI was 50.45. Compared with the parameters of the low PNI group (n=76), high PNI was significantly associated with adenocarcinoma type, stage III, better ECOG and comprehensive treatment modality. The univariate analysis demonstrated that OS was superior when PNI ≥50.45, albumin ≥35 g/l, platelet-lymphocyte ratio (PLR) ≥163 and ECOG <2, and when the patient received a comprehensive treatment modality. In the multivariate analysis, PNI, TNM stage and treatment strategy were identified as independent predictors of survival in this study. This retrospective study demonstrated that a low PNI was related to worse overall survival in patients with stage III/IV NSCLC who received platinum-based chemotherapy. These data provided a conceptual basis for further research on the clinical application of the PNI index for patients receiving chemotherapy for intermediate- and advanced-stage NSCLC.

[Clinicopathological features and prognosis of 488 patients with neuroendocrine tumors]

Objective: To investigate the clinicopathological features and prognosis of patients with neuroendocrine tumors (NETs). Methods: The clinicopathologic data of enrolled patients with NETs between October 2012 and October 2017 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. Results: Among the 488 NETs patients, the average age was (51.0±15.8) years, and the sex ratio (male/female) was 1∶1.1. Of the NETs, 370 were located in the digestive system (75.8%), 63 were pulmonary (12.9%), 14 were mediastinal (2.9%), 7 were of unknown primary origin (1.4%), and 34 were located in other sites (7.0%). Among the NETs, the pancreas, rectum and stomach were the most common sites. In the digestive system NETs, the most common tumor grade was G1 (190 cases, 51.4%), followed by G2 (143 cases, 38.6%) and NET-G3 (37 cases, 10.0%). In pulmonary NETs, typical and atypical carcinoid tumors was 47.6% and 52.4%, respectively. There were 310 patients at stage Ⅰ/Ⅱ, 53 at stage Ⅲ, 69 at stage Ⅳ and 56 at stage undiagnosed, respectively. The relationships among age, stage, grade, metastasis, treatment and prognosis were analyzed. All these factors could influence the survival rate of NET patients. Multivariate Cox analysis showed that age (>50 years old) (HR=2.831, 95%CI:1.414-7.029, P=0.025) and distant metastasis (HR=10.208, 95%CI:4.110-25.355, P<0.001) were independent risk factors. Conclusions: The most common primary sites of NETs are the pancreas, rectum, and stomach. Age and distant metastasis are independent risk factors for the prognosis of NETs.

[Surveillance of key parasitic diseases in Baise City from 2006 to 2015]

OBJECTIVE

To understand and master the infection status of key parasitic diseases in Baise City from 2006 to 2015, so as to provide evidence for the development and adjustment of the control strategy for parasitic diseases.

METHODS

The relevant information of the final evaluation of the key parasitic diseases in 12 counties (cities and districts) of Baise City from 2006 to 2015 was collected, and analyzed.

RESULTS

During the period of 2006-2015, a total of 20 654 person-times were investigated for parasitic diseases in Baise City and 1 147 persons were infected, with an average infection rate of 5.55%. In 2006, the infection rate was the highest (28.67%, 362/1 254), while the lowest was in 2013 (2.08%, 44/2 113). The infection rate of Clonorchis sinensis was the highest, and the infection rate of Ascaris lumbricoides was the second. The infection rates of the males and females were 5.35% (631/11 795) and 5.82% (516/8 859) respectively, with no significant difference between them (χ² = 2.175, P > 0.05). The highest infection rate existed in the 40-49 years group, the rural residents, the farmers and the crowd with the educational level of senior high middle school or above.

CONCLUSIONS

The infection rate of parasitic diseases presents a decline trend overall in Baise City from 2006 to 2013, however it rebounded in 2014 and 2015. The next step is to strengthen the prevention and control of parasitic diseases by promoting health education, regular insect repellent, and fecundity management.

[Functional lateralization of major Chinese language cortex for presurgical evaluation in neurosurgery]

Objective: To investigate the functional lateralization of major Chinese language cortex in patients with cerebral arteriovenous malformation (AVM) in dominant hemispheric via functional magnetic resonance imaging (fMRI). Methods: Nine right-handed normal volunteers and fourteen patients with cerebral AVM in dominant hemisphere diagnosed in Beijing Tiantan Hospital between December 2017 and June 2018 were included. Three language tasks (semantic judgment, word reading, and listening comprehension) were applied to activate language areas. Lateralization index (LI) was used to show the dominant hemisphere. Results: In the control group, right-sided lateralization of BOLD signal activations was observed in 0/27 (0%) of the language tasks. While in the AVM patients, right-sided lateralization of BOLD signal activations was observed in 8/42 (19%) language tasks. The difference was statistically significant (χ(2)=5.73, P=0.019). Conclusions: The dominant hemisphere of different language tasks may be different in patients with cerebral lesions. Compared with normal controls, patients with cerebral AVM in dominant hemispheric are more likely to have right-sided lateralization of language cortex.

[Diffusion tensor imaging of the central auditory system in the elderly]

Objective:To evaluate the changes in the central auditory system of presbycusis by applying auditury brainstem response (ABR) and diffusion tensor imaging (DTI). Method:A total of twenty-five elderly subjects with expressed presbycusis, eight elderly subjects with normal hearing and fifteen healthy volunteers as young controls were enrolled in the study. Each participant was examined using ABR and DTI. ABR measures were obtained from all the subjects. The fractional anisotropy (FA) was measured at two brain regions of the auditory pathway-the inferior colliculus (IC) and Heschl's gyrus. Result:Higher FA values were recorded at the left side of the Heschl's gyrus in all three groups (P<0.05). There were no significant differences between the left and right side of the ABR results and FA values of inferior colliculus in the three groups (P>0.05). Aging increased ABR peak latencies, yet did not change the Ⅰ-Ⅴ interpeak latency interval. Comparing with the elderly subjects with normal hearing group, the wave Ⅴ latencies of the presbycusis group were prolonged (P<0.05). Comparing with the healthy control group, the FA values of the IC were reduced in both of the elderly subjects with normal hearing group and the presbycusis group (P<0.05). No statistically differences were observed between the presbycusis group and the elderly subjects with normal hearing group in the FA values of the IC (P>0.05). Significant differences between all groups were found in the FA values of the Heschl's gyrus, with higher values in the elderly subjects with normal hearing group than in the presbycusis group and even higher values in the healthy control group than in the elderly subjects with normal hearing group (P<0.05). Conclusion:The results indicated that the age-related microstructural changes exist in the central part of the auditory system, which are more obvious in the patients with presbycusis.

[Characterization and uncertainty evaluation of aqueous reference materials for cholesterol]

Objective: Characterization and evaluation of the uncertainty of the reference materials of cholesterol in aqueous solution. Methods: The certified reference material GBW09203b was weighed accurately and dissolved into methyl cyclodextrin aqueous solution to prepare six kinds of candidate reference materials of cholesterol according to the concentration. The materials were tested for homogeneity and stability using routine methods and were evaluated the uncertainty derived from the inhomogeneity and instability. The uncertainty due to measurement was derived from the purity of the raw material, the weighing and the density measurement. The certified values and expanded uncertainties were calculated according to the ISO Guide. The expanded uncertainty of the certified value was the combination of standard uncertainty of measurement, inhomogeneity and instability. The coverage factor, k, was determined from the Student's t-distribution corresponding to the calculated effective degrees of freedom and 95% level of confidence. Results: It showed that the six candidate reference materials were homogeneous and were tested to be stable for at least 1 year at -70 ℃ and -20 ℃ using the isochronous stability study. The relative uncertainties due to the inhomogeneity were 0.14%, 0.11%, 0.13%, 0.47%, 0.39% and 0.11%. The relative uncertainty due to the instability was 0.25% at -70 ℃. The uncertainties of measurement were 0.06%, 0.05%, 0.05%, 0.05%, 0.05% and 0.05%.The certified values (reference value ± expanded uncertainty, mmol/L) were as follows: (0.651±0.004), (1.310 ±0.007), (2.574±0.015), (5.210±0.055), (7.710±0.072), (10.242±0.056) mmol/L. Conclusions: Six kinds of certified reference materials for cholesterol in aqueous solution have been prepared, which were homogeneity, stable and reliable. It showed that the uncertainty of measurement was very small compared with the uncertainty due to inhomogeneity and instability.

Clinical efficacy of fiberoptic ductoscopy in combination with ultrasound-guided minimally invasive surgery in treatment of plasma cell mastitis

OBJECTIVES

To analyze clinical efficacy between fiberoptic ductoscopy plus ultrasound-guided minimally invasive irrigation and lesion resection in treating plasma cell mastitis (PCM), aiming to provide clinical evidence for treating PCM.

MATERIALS AND METHODS

119 patients undergoing fiberoptic ductoscopy plus ultrasound-guided minimally invasive surgery in Ningxia People's Hospital were allocated into the breast duct irrigation group, and 95 counterparts receiving lesion resection in the Affiliated Hospital of Ningxia Medical University into the control group. Clinico-pathological characteristics and therapeutic effect were compared between two groups.

RESULTS

The cure rate in the breast duct irrigation group was 98.31% (117/119), significantly higher than 90.53% in the control group (p < 0.05). In the breast duct irrigation group, overall treatment time was 20.13 days, significantly longer than 15.15 days in the control group (p < 0.05). During postoperative follow-up, no recurrence was observed, significantly lower compared with 48.8% (42/86) in the control group. The degree of satisfaction in the breast duct irrigation group was 95.79% (114/119), significantly higher compared with 74.74% (71/95) in the control group.

CONCLUSIONS

Fiberoptic ductoscopy plus with ultrasound-guided minimally invasive drainage is a novel and effective treatment of PCM with high cure rate, low recurrence rate, slight pain, and effectively maintains breast integrity.

Members of the receptor for advanced glycation end products axis as potential therapeutic targets in patients with lupus nephritis

The relationship of inflammation and the expression of full-length receptor for advanced glycation end products (flRAGE) on monocytes, plasma levels of RAGE ligand high mobility group box protein 1 (HMGB1), soluble RAGE (sRAGE) and endogenous secretory RAGE (esRAGE) was assessed to elucidate the effect of HMGB1/DNA/RAGE-mediated innate inflammatory responses in patients with lupus nephritis. Cell surface expression of flRAGE was elevated on the monocytes of lupus patients, correlated with plasma HMGB1 levels. Plasma sRAGE level negatively correlated with systemic lupus erythematosus (SLE) disease activity index. Plasma esRAGE level was significantly lower in SLE patients with flare while esRAGE/sRAGE ratio negatively correlated with complement C3 level. HMGB1 alone could moderately induce ex vivo IL-6 production from monocytes, resulting in activation of intracellular p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase and nuclear factor (NF)-κB. Moreover, toll-like receptor-9 ligand together with HMGB1 exhibited a synergistic effect on IL-6 and IL-12p70 secretions and the phosphorylation of p38 MAPK and NF-κB. Therefore, over-expression of flRAGE in lupus may lead to the amplification of RAGE ligands-mediated inflammatory responses through the activation of p38 MAPK and NF-κB. Plasma sRAGE may serve as a potential biomarker for disease activity and a future therapeutic target in SLE.

Characterization of insertional variation of porcine endogenous retroviruses in six different pig breeds

Pigs may need to be exploited as xenotransplantation donors due to the shortage of human organs, tissues and cells. Porcine endogenous retroviruses (PERVs) are a significant obstacle to xenotransplantation because they can infect human cells in vitro and have the potential for transmission of unexpected pathogens to humans. In this research, 101 pigs, including four commercial breeds (23 Berkshire, 13 Duroc, 22 Landrace and 14 Yorkshire pigs), one native breed (19 Korean native pigs) and one miniature breed (10 NIH miniature pigs) were used to investigate insertional variations for 11 PERV loci (three PERV-A, six PERV-B and two PERV-C). Over 60% of the pigs harbored one PERV-A (907F8) integration and five PERV-B (B3-3G, B3-7G, 742H1, 1155D9 and 465D1) integrations. However, two PERV-A loci (A1-6C and 1347C1) and one PERV-B locus (B3-7F) were absent in Duroc pigs. Moreover, two PERV-C loci (C2-6C and C4-2G) only existed in Korean native pigs and NIH miniature pigs. The results suggest that PERV insertional variations differ among pig breeds as well as among individuals within a breed. Also, the results presented here can be used for the selection of animals that do not have specific PERV integration for xenotransplantation research.

Expression of hepatitis B virus 1.3-fold genome plasmid in an SV40 T-antigen-immortalized mouse hepatic cell line

AIM: To investigate the expression of the hepatitis B virus (HBV) 1.3-fold genome plasmid (pHBV1.3) in an immortalized mouse hepatic cell line induced by SV40 T-antigen (SV40T) expression.

METHODS: Mouse hepatic cells were isolated from mouse liver tissue fragments from 3-5 d old Kunming mice by the direct collagenase digestion method and cultured in vitro. The pRSV-T plasmid was transfected into mouse hepatic cells to establish an SV40LT-immortalized mouse hepatic cell line. The SV40LT-immortalized mouse hepatic cells were identified and transfected with the pHBV1.3 plasmid. The levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in the supernatant were determined by an electrochemiluminescence immunoassay at 24, 48, 72 and 96 h after transfection. The expressions of HBsAg and hepatitis B c antigen (HBcAg) in the cells were investigated by indirect immunofluorescence analysis. The presence of HBV DNA replication intermediates in the transfected cells and viral particles in the supernatant of the transfected cell cultures was monitored using the Southern hybridization assay and transmission electronic microscopy, respectively.

RESULTS: The pRSV-T plasmid was used to immortalize mouse hepatocytes and an SV40LT-immortalized mouse hepatic cell line was successfully established. SV40LT-immortalized mouse hepatic cells have the same morphology and growth characteristics as primary mouse hepatic cells can be subcultured and produce albumin and cytokeratin-18 in vitro. Immortalized mouse hepatic cells did not show the characteristics of tumor cells, as alpha-fetoprotein levels were comparable (0.58 ± 0.37 vs 0.61 ± 0.31, P = 0.37). SV40LT-immortalized mouse hepatic cells were then transfected with the pHBV1.3 plasmid, and it was found that the HBV genome replicated in SV40LT-immortalized mouse hepatic cells. The levels of HBsAg and HBeAg continuously increased in the supernatant after the transfection of pHBV1.3, and began to decrease 72 h after transfection. The expressions of HBsAg and HBcAg were observed in the pHBV1.3-transfected cells. HBV DNA replication intermediates were also observed at 72 h after transfection, including relaxed circular DNA, double-stranded DNA and single-stranded DNA. Furthermore, a few 42 nm Dane particles, as well as many 22 nm subviral particles with a spherical or filamentous shape, were detected in the supernatant.

CONCLUSION: SV40T expression can immortalize mouse hepatic cells, and the pHBV1.3-transfected SV40T-immortalized mouse hepatic cell line can be a new in vitro cell model.

Duplicated CCAAT/enhancer-binding protein β (C/EBPβ) gene: transcription and methylation changes in response to dietary betaine in Landes goose liver

The CCAAT/enhancer-binding protein β gene (C/EBPβ) is one of the key regulating factors of lipid metabolic balance in the liver. To better understand how C/EBPβ affects lipid accumulation in the Landes goose liver, its DNA was cloned. The goose C/EBPβ DNA sequence (2,075 bp) contains a 984-bp open reading frame and part of the 5'-flanking region, and shares 96.66 and 62.07% similarity with the chicken and human sequences at the amino acid level, respectively. Tissue expression profiling showed that the relative expression level was high in the liver and adipose tissue. To understand the effect of betaine on C/EBPβ in goose liver, the relative expression levels of C/EBPβ were detected under different treatments. Compared with the control group, C/EBPβ expression increased in the high-carbohydrate group (P < 0.01) and decreased in the betaine treatment group (P > 0.05). Using bisulfite sequencing PCR, the gene methylation status was analyzed among the different treatment groups. None of the 54 CpG sites in the promoter region or the 28 CpG sites in the structural domain of the coding region showed any significantly different methylation patterns among the groups. Taken together, the results showed that betaine decreased the goose C/EBPβ gene expression, but did not directly regulate its methylation. The data may form the basis for further investigation of the mechanisms of the effect of C/EBPβ on the regulation of lipometabolism in the goose liver and the effect of betaine on lipid metabolic genes at the molecular level.

Accuracy of vessel-encoded pseudocontinuous arterial spin-labeling in identification of feeding arteries in patients with intracranial arteriovenous malformations

BACKGROUND AND PURPOSE

Identifying feeding arteries of intracranial AVMs is very important for preoperative evaluation. DSA remains the reference standard for diagnosis but is invasive. Our aim was to evaluate the diagnostic accuracy of vessel-encoded pseudocontinuous arterial spin-labeling in identifying feeding arteries of intracranial AVMs by using DSA as the criterion standard.

MATERIALS AND METHODS

Eighteen patients with AVMs were examined with vessel-encoded pseudocontinuous arterial spin-labeling and DSA. Three postlabeling delays (postlabeling delay = 1, 1.3, and 1.6 seconds) were applied in 6 patients, and a single postlabeling delay (1 second) was applied in the remainder. Perfusion-weighted images were decoded into individual vascular territories with standard and relative tagging efficiencies, respectively. The supply fraction of each feeding artery to the AVM was calculated. The within-subject ANOVA was applied to compare supply fractions acquired across 3 postlabeling delays. Receiver operating characteristic analysis curves were calculated to evaluate the diagnostic accuracy of vessel-encoded pseudocontinuous arterial spin-labeling for identifying the feeding arteries of AVMs.

RESULTS

There were no significant differences in supply fractions of the 3 major arteries to AVMs acquired with 3 postlabeling delays (P > .05). For vessel-encoded pseudocontinuous arterial spin-labeling with standard labeling efficiencies, the area under the receiver operating characteristic analysis curve was 0.942. The optimal cutoff of the supply fraction for identifying feeding arteries was 15.17%, and the resulting sensitivity and specificity were 84.62% and 93.33%, respectively. For vessel-encoded pseudocontinuous arterial spin-labeling with relative labeling efficiencies, the area under the receiver operating characteristic analysis curve was 0.957. The optimal cutoff of the supply fraction was 11.73%, which yielded an 89.74% sensitivity and 93.33% specificity.

CONCLUSIONS

The contribution fraction of each feeding artery of the AVM can be reliably estimated by using vessel-encoded pseudocontinuous arterial spin-labeling. Vessel-encoded pseudocontinuous arterial spin-labeling with either standard or relative labeling efficiencies offers a high level of diagnostic accuracy compared with DSA for identifying feeding arteries.

Molecular analysis of the coat protein gene of peanut stripe virus from China

Peanut stripe virus (PStV) is one of the most common viruses infecting peanut that causes great economic losses every year. The 3ʹ-terminal 1082 bp of 74 PStV isolates collected from 12 districts of Shandong province, China were sequenced. Their coat protein (CP) genes were 864 bp in length and shared identities of 98.0%~100% and 98.3% ~100% at nt and aa levels. The identities between the CP genes of these isolates and other 36 isolates from the GenBank were 93.5%~100% and 92.0%~100% at nt and aa levels, respectively. PStV isolates can be clustered into two phylogenetic groups. The isolates from United States, mainland China, and Indonesia formed group I and those from Viet Nam, Thailand, and Taiwan formed group II. The PStV isolates in group I can be further classified to two subgroups. The gene flow of PStV populations within a country was frequent, but that between countries was infrequent.

Isotherm and kinetic behavior of adsorption of anion polyacrylamide (APAM) from aqueous solution using two kinds of PVDF UF membranes

To determine the isotherm parameters and kinetic parameters of adsorption of anion polyacrylamide (APAM) from aqueous solution on PVDF ultrafiltration membrane (PM) and modified PVDF ultrafiltration membrane (MPM) is important in understanding the adsorption mechanism of ultrafiltration processes. Effect of variables including adsorption time, initial solution concentration, and temperature were investigated. The Redlich-Peterson equation of the five different isotherm models we chose was the most fitted model, and the R(2) was 0.9487, 0.9765 for PM and MPM, respectively; while, the pseudo-first-order model was the best choice among all the four kinetic models to describe the adsorption behavior of APAM onto membranes, suggesting that the adsorption mechanism was a chemical and physical combined adsorption on heterogeneous surface. The thermodynamic parameters were also calculated from the temperature dependence (Δ(r)G(m)(θ), Δ(r)H(m)(θ), Δ(r)S(m)(θ)), which showed that the process of adsorption is not spontaneous but endothermic process and high temperature favors the adsorption.

Ovarian hyperstimulation syndrome: an analysis of patient characteristics in the Asian population

INTRODUCTION

We aimed to identify the variables associated with ovarian hyperstimulation in Asian patients and compare them with western standards.

METHODS

This is a retrospective case record analysis of 79 patients with ovarian hyperstimulation at a tertiary restructured hospital.

RESULTS

Gonadotropin doses resulting in hyperstimulation did not vary between long and antagonist cycles in women less than 35 years with polycystic ovaries (PCO). Mean oestradiol levels at hyperstimulation were not different between PCO and non-PCO patients in a long cycle. Hyperstimulation was mostly due to higher starting doses. Total follicle counts of more than 20 on Day 5-7 after stimulation may be predictive of subsequent hyperstimulation. Hyperstimulation tended to be more severe in lean PCO patients, and prophylactic albumin helped to reduce its severity.

CONCLUSION

Gonadotropin doses at stimulation should start at 150 iu or less in women below 35 years of age, with a step up of 37.5 iu, as necessary. Transfer should be abandoned in the presence of high oestradiol levels (more than 5,000 pg/ml), when the total number of intermediate and large follicle count exceeds 30 on the day of oocyte retrieval, or when more than 19 eggs are retrieved. Variables in the Asian population appear to be similar to those in the western population.

Characterization and anti-fouling performance of nano-Al₂O₃/PVDF membrane for Songhua river raw water filtration

Polyvinylidene fluoride (PVDF) flat ultrafiltration membranes modified by nano-sized alumina (Al₂O₃) particles were prepared by phase inversion process and their properties and anti-fouling performances were examined. The influence of three types of natural organic matters on the modified membrane fouling was also studied. Raw water was taken from two different locations, i.e., Harbin and Zhaoyuan, of Songhua River. Dissolved organic compounds in the raw water were fractionated using XAD resins into three fractions, i.e., hydrophobic fraction, transphilic fraction, and hydrophilic fraction (HPI). The three adsorbed compounds were further eluted and dissolved into distilled water respectively to prepare the feed for the fouling tests. All solutions were adjusted to a concentration of 10.6 mg C/L, which equals to the total organic carbon (TOC) of the raw water. Results show that the addition of nano-Al₂O₃ particulars did not affect the inherent traits of the PVDF membranes, however, its surface hydrophilic properties were improved significantly with the addition of nanoparticles and anti-fouling performance was enhanced as well. The HPIs in the Songhua River were the main foulant, causing more fouling to membrane than hydrophobic and transphilic matters.

Molecular variability of five Cucumber mosaic virus isolates from China

Cucumber mosaic virus (CMV) isolates are currently divided into two main groups, I and II according to their genomic sequences. The group I is further divided into two subgroups IA and IB. We performed a phylogenetic analysis of the genome regions containing 1a, 2a, 2b, coat protein (CP), and movement protein (MP) genes of 5 CMV isolates from China and other 28 CMV isolates available in the GenBank. The results indicated that CMV isolates could be genetically divided into three groups I, II, and III according to the genes encoding MP, CP, 1a, and 2a proteins and to the 2 groups according to the gene 2b. Group I could be further divided into two subgroups (IA and IB) according to the genes encoding CP, MP, 2a, and 2b proteins and to the three subgroups (IA, IB, and IC) according to the gene encoding 1a protein. Four of 5 examined Chinese CMV isolates belonged to the subgroup IB, while the remaining isolate was a natural inter-subgroup reassortant. We found that the 2b gene of CMV was under positive selection, while the other genes were under negative selection. No evidence of the selection associated with a host adaptation or geographic distribution was found.

Identification of differentially expressed genes in distinct skeletal muscles in cattle using cDNA microarray

The 788-gene microarray was manufactured using selected elements from three different cDNA libraries in order to identify molecular processes that determine phenotypic characteristics between loin (M. longissimus thoracis) and round (M. semimembranosus) muscles. Microarray analyses identified 24 differentially expressed genes between the two muscles investigated. Five of the genes were verified by quantitative RT-PCR and three of them were mapped on bovine chromosomes using 5,000 rad bovine radiation hybrid (RH) panel. The map locations indicated that they were mapped in the same chromosomal regions where IMF and growth QTLs were located, suggesting that they are most possible positional candidate genes for the traits.

More evidence supports the association of PPP3CC with schizophrenia

Calcineurin is a calcium/calmodulin-dependent protein phosphatase composed of two subunits, a regulatory subunit of calcineurin B (CNB) and a catalytic subunit of calcineurin A (CNA). PPP3CC is the gamma isoform of CNA located at the chromosome 8p21.3 region. To evaluate the association between PPP3CC and schizophrenia in the Taiwanese population, 10 single nucleotide polymorphism (SNP) markers across the gene were genotyped by the method of MALDI-TOF in 218 schizophrenia families with at least two affected siblings. One SNP (rs2272080) located around the exon 1 untranslated region was nominally associated with schizophrenia (P=0.024) and significantly associated with the expression of PPP3CC in lymphoblast cell line; the TT and TG genotype had significantly higher relative expression levels than the GG genotype (P=0.0012 and 0.015, respectively). In further endophenotype stratification, the single locus of rs2272080 and the haplotypes of both two-SNP haplotype (rs7833266-rs2272080) and seven-SNP haplotype (rs2461491-rs2469758-rs2461489-rs2469770-rs2449340-rs1482337-rs2252471) showed significant associations with the subgroup of schizophrenia with deficits of the sustained attention as tested by the continuous performance test (CPT, P<0.05) and the executive functioning as tested by the Wisconsin Card Sorting Test (WCST, P<0.05). The results suggest that PPP3CC gene may be a true susceptibility gene for schizophrenia.

Growth hormone deficiency and supplementation at in-vitro fertilisation

INTRODUCTION

This study aims to evaluate the differences in oocyte stimulation, endometrial thickness, fertilisation rate and embryo quality at in-vitro fertilisation (IVF) in patients with documented growth hormone (GH) deficiency, after GH supplementation.

METHODS

This was a retrospective analysis of 20 cases of patients who were pregnant and had GH supplementation during IVF at the Singapore General Hospital between 1993 and 2003. All these patients had previously failed IVF due to poor stimulation, poor egg quality, poor fertilisation at intracytoplasmic sperm injection (ICSI) or failed implantation, and they had documented GH deficiency. These initial cycles were compared with their subsequent IVF cycles with GH supplementation. A non-parametric test was used for statistical analysis.

RESULTS

Embryo quality, determined by scoring the embryos on Day two using morphology, improved significantly after supplementation of GH (p-value is less than 0.001, median embryo score increased from 10.7 to 16). There was also a statistically significant increase in the fertilisation rate for those patients who had ICSI. There was no statistical difference in the number of oocytes retrieved or in the mean endometrial thickness with GH.

CONCLUSION

This study implies that GH supplementation may improve embryo quality in selected patients with GH deficiency. Its role in improving fertilisation rate at ICSI merits further research and evaluation.

Detection of Circulating Antigen with a MAb-Based Sandwich-ELISA and Its Comparison with Specific IgM Detection in Sera of Patients with Hemorrhagic Fever with Renal Syndrome

A monoclonal antibody (1H2) against nucleocapsid protein of Hantavirus was developed. A sandwich enzyme-linked immunosorbent assay (ELISA) with the monoclonal antibody (MAb) was established and evaluated for detecting circulating antigen (CAg) in serum of patients with hemorrhagic fever with renal syndrome (HFRS). Results were compared to that of an immunoglobulin M (IgM)-detecting ELISA. Of 143 patients with HFRS, 106 were positive for CAg of Hantavirus and 128 positive for specific IgM. Among the 15 HFRS patients in whom specific IgM was not detected, 10 were positive for CAg. Of 100 controls including 40 hepatitis B cases, 40 measles cases, and 20 healthy persons all were negative for both CAg and specific IgM. Detection of Hantavirus CAg with a MAb-based sandwich ELISA (MBS-ELISA) established in the present study adds a new diagnostic tool for HFRS, and it increases the diagnostic rate to conventional specific IgM detection, especially for patient in the early stage of HFRS.

Intrapartum maternal sinus bradycardia with spontaneous resolution following delivery

Pregnancy is a normal physiological state that is characterised by significant adaptive changes, many of which take place in the cardiovascular system. These adaptations are believed to be the cause for the increased incidence in cardiac arrhythmias in pregnancy and particularly, in labour. We report an unusual case of a healthy 32-year-old primigravida who developed profound intrapartum bradycardia which persisted throughout labour. Spontaneous recovery to pre-labour baseline heart rate occurred following spontaneous vaginal delivery. Maternal and foetal statuses remained satisfactory during labour. This case report underscores the importance of recognising that arrhythmias in various forms are common in labour. In the absence of detectable underlying cardiac disease or maternal and foetal compromise, continuation of the labour with a view to vaginal delivery should be the goal.

Molecular cloning and characterization of bovine PRKAG3 gene: structure, expression and single nucleotide polymorphism detection

The protein kinase adenosine monophosphate-activated gamma3-subunit (PRKAG3) gene encodes a muscle-specific isoform of the regulatory gamma-subunit of adenosine monophosphate-activated protein kinase, which plays a key role in regulating energy homeostasis in eucaryotes. It is well known that mutations in the PRKAG3 gene affect high glycogen content in the porcine skeletal muscle and, consequently, meat quality. The genomic structure and sequence of the bovine PRKAG3 were analysed from a Korean cattle BAC clone. The bovine PRKAG3 gene comprises 13 exons and spans approximately 6.8 kb on BTA2. From 5' and 3'-rapid amplification of cDNA ends experiments, the full-length cDNA of bovine PRKAG3 has been identified, encoding a deduced protein of 465 amino acids. Two splice isoforms, generated by the alternative splicing of exon 2, were also identified. Northern blot analysis demonstrated that, similar to other species, the bovine PRKAG3 transcript was only expressed in skeletal muscle. Seven single nucleotide polymorphisms, including two previously identified variants, were detected in four Bos taurus cattle breeds. The bovine PRKAG3 gene described in this study may be involved in muscle-related genetic diseases or meat quality traits in cattle.

Uterine artery embolisation for symptomatic fibroids in a tertiary hospital in Singapore

INTRODUCTION

Transcatheter uterine artery embolisation (UAE) for the treatment of symptomatic uterine enlargement due to fibroids has been performed in several overseas centres with promising results. We report our experience with UAE in Singapore General Hospital.

MATERIALS AND METHODS

Twenty women with symptomatic uterine fibroids who declined surgery were treated by transcatheter UAE. The uterine arteries were selectively catheterised and embolised with polyvinyl alcohol particles. Post-procedure analgesia was administered via a patient-controlled analgesia pump. The patients were followed up at regular intervals clinically and with transabdominal ultrasonography.

RESULTS

Transcatheter UAE was performed on all patients with no major complications. Nineteen patients had both uterine arteries embolised while 1 patient had only the right uterine artery embolised on account of hypoplasia of the left uterine artery. The mean hospital stay was 3.5 days (range, 2 to 9). At a mean follow-up of 56 weeks (range, 6 to 168), all patients reported improvements in their presenting symptoms. Objective improvement in terms of reduction of uterine and fibroid sizes was determined on ultrasonography. The median size of the uterine volume decreased from 308 to 187 mL while the median diameter of the largest fibroid reduced from 6.2 to 4.6 cm. The median haemoglobin level increased to 12.7 g/dL from the pre-procedural median of 9.9 g/dL. One patient, who initially responded with a decrease in uterine and dominant fibroid size, became symptomatic (menorrhagia) at 6 months post-embolisation. She underwent a repeat procedure with complete resolution of symptoms. A second patient had recurrence of symptoms at 12 months, but was subsequently lost to follow-up.

CONCLUSION

Mid-term results of UAE for the treatment of symptomatic fibroids in our hospital indicate this to be a safe and effective therapeutic option.

A survey of fasting during pregnancy

INTRODUCTION

Fasting during the month of Ramadan is compulsory in the Muslim faith. Although pregnant women may be exempted, many still choose to fast while others are more careful in practising it. This survey examines the practice of fasting among pregnant Muslim women in Singapore based on the prevalence in relation to factors such as parity, social and economic circumstances. It also analyses the factors that influence the decision to fast and the successful completion of the fast, and examines their knowledge, belief and attitudes on fasting during the holy month of Ramadan.

METHODS

This is a retrospective study of all Muslim women who were pregnant and received antenatal care in our hospital during the month of Ramadan from 17 November 2001 to 16 December 2001. A four-page questionnaire was mailed to all eligible subjects in March 2002.

RESULTS

Of 202 eligible subjects, 125 responded via mail and 57 via the phone, yielding a response rate of 90 percent. Most women chose to fast during pregnancy, and they do so with adequate support from their spouses and family members. Most of them do not experience any adversities during fasting and even if they do, most were able to overcome them. Most women adopt a positive attitude towards fasting. However, there is a lack of basic religious knowledge among many pregnant women pertaining to the Muslim law of fasting during pregnancy.

CONCLUSION

Doctors and health workers need to understand the religious obligations of a Muslim towards fasting during Ramadan. Only through this can a doctor adequately counsel Muslim patients and allow informed decision with regards to fasting. With respect to pregnant women, provisions are allowed for them not to observe fasting.

[Study on the cost-effectiveness, benefit and utility analysis on the infant inoculation hepatitis B vaccine in Shanghai]

OBJECTIVE

To study the cost-effectiveness, benefit and utility of infant hepatitis B vaccination in Shanghai from 1992 to 2001.

METHODS

To calculate the cost of hepatitis B vaccination by cost analysis method. Both the numbers of persons with HBsAg positive and patient with hepatitis B, cirrhosis and liver cancer decreased as the index of direct effect. To study the sick-time and the cost of treating hepatitis B, cirrhosis and liver cancer patients, a face to face questionnaire was used and quasi method was adopted to understand the effect of cure and the course of hepatitis B. The cost benefit analysis method was also used to calculate the cost benefit of HBV vaccine. The disability adjusted life years (DALY) was regarded as an index of utility to measure the disease burden.

RESULTS

Input of 501,129.49 Yuan might have the result of reducing one liver cancer patient, ten cirrhosis patients, one hundred chronic hepatitis B patients and one thousand HBsAg positive people. The cost of hepatitis B vaccination was 0.24 hundred million Yuan during the past ten years in Shanghai, which had obtained the total benefit value of 41.22 hundred million Yuan, with a cost benefit ratio of 1:172 Yuan. It was estimated that the total disease burden of hepatitis B, cirrhosis and liver cancer patients was 59,762.55 DALY in order to reduce one DALY loss cost of 402.50 Yuan.

CONCLUSION

HBV vaccine inoculation in infants seemed to be a low-cost input and high-effect output strategy.

Investigating the infertile couple

INTRODUCTION

Investigations play a pivotal role in the workup for infertility. The results must be interpreted carefully as these assess dynamic function. Evidence-based guidelines are useful in the selection of appropriate tests.

MATERIALS AND METHODS

A review of current evidence-based guidelines for the investigation and management of the infertile couple is undertaken.

RESULTS

The main areas that correlate with fecundability are ovulatory function, tubal patency and semen analysis.

CONCLUSION

The appropriate selection of investigations based on problem areas identified by history and physical examination would guide the physician in the management of the infertile couple.

Requirement for yeast RAD26, a homolog of the human CSB gene, in elongation by RNA polymerase II

Mutations in the human CSB gene cause Cockayne syndrome (CS). In addition to increased photosensitivity, CS patients suffer from severe developmental abnormalities, including growth retardation and mental retardation. Whereas a deficiency in the preferential repair of UV lesions from the transcribed strand accounts for the increased photosensitivity of CS patients, the reason for developmental defects in these individuals has remained unclear. Here we provide in vivo evidence for a role of RAD26, the counterpart of the CSB gene in Saccharomyces cerevisiae, in transcription elongation by RNA polymerase II, and in addition we show that under conditions requiring rapid synthesis of new mRNAs, growth is considerably reduced in cells lacking RAD26. These findings implicate a role for CSB in transcription elongation, and they strongly suggest that impaired transcription elongation is the underlying cause of the developmental problems in CS patients.

[Study on computer aided design system of anterior prosthesis in terms of artificial neural network]

OBJECTIVE

This study was to develop computer aided design system of anterior prosthesis, which can improve information communication among doctors, technicians, patients and raise anterior prosthesis cosmetic effect.

METHODS

Digital camera was used for image capture; Space field method, neighboring field average method, midst value filter method, and image average method were used for image pre-process; sample teeth were constructed; anterior prosthesis were automatically designed through tooth feature extraction.

RESULTS

86 patients were prosthetically designed through this CAD system with excellent results.

CONCLUSION

This system implemented anterior prosthesis CAD rapidly, guided clinical application and promoted information process in the field of prosthetics.

Effects of chilling on sampling of bacteria attached to swine carcasses

Two microbiological sampling techniques, excision and sponge swabbing, were compared by determining counts of aerobic bacteria, coliforms and injured coliforms from 20 de-haired swine carcasses before and after chilling. Excised jowl skin produced significantly greater counts of the three types of bacteria than sponge swabs. Aerobic bacteria, coliforms and injured coliforms recovered by sponge swabbing carcasses before chilling were 11.6%, 0.9% and 11.0% of excised samples, respectively; the corresponding percentages recovered after chilling were 23.9%, 11.1% and 5.0%. Numbers of all bacteria present on the post-chill carcasses were substantially lower than on the pre-chill carcasses. Excision usually produced more countable plates for coliforms and injured coliforms on chilled carcasses than sponge swabbing and therefore, is more suitable in estimating low numbers of faecal bacteria on chilled carcasses. To explore the possible structural bases for these findings, skin samples were inoculated with 10(2)-10(7) cfu cm(-2) faecal bacteria and examined by scanning electron microscopy. Chilled samples showed bacteria and biofilm embedded in superficial crevices, which underlies a possible reason for the lower recovery of bacterial cells by the sponge swabbing. The study indicates that the differences between sampling techniques may be a result of the chilling process of swine carcasses.

Variability in CD34+ cell counts in umbilical cord blood: implications for cord blood transplants

OBJECTIVE

To determine if total nucleated cell counts alone are sufficient for predicting the efficacy of cord blood units for transplant from neonatal umbilical cord blood samples.

METHODS

Umbilical cord blood samples were collected from 200 mothers at delivery and the cord blood units processed. The total nucleated cells and CD34+ cells were enumerated and compared for each sample.

RESULTS

Despite an apparent linear correlation between total nucleated cell counts and CD34+ cell counts, each group of total nucleated cell counts demonstrated a high degree of variation in CD34+ cell counts and could be as low as 0.1% of total nucleated cell counts.

CONCLUSIONS

Large variations in CD34+ cell counts per total nucleated cell count are present for cord blood units from neonatal umbilical cord samples. Hence a CD34+ cell count for each cord blood unit would improve selection of samples for transplant.

Requirement of DNA polymerase eta for error-free bypass of UV-induced CC and TC photoproducts

The yeast RAD30-encoded DNA polymerase eta (Poleta) bypasses a cis-syn thymine-thymine dimer efficiently and accurately. Human DNA polymerase eta functions similarly in the bypass of this lesion, and mutations in human Poleta result in the cancer prone syndrome, the variant form of xeroderma pigmentosum. UV light, however, also elicits the formation of cis-syn cyclobutane dimers and (6-4) photoproducts at 5'-CC-3' and 5'-TC-3' sites, and in both yeast and human DNA, UV-induced mutations occur primarily by 3' C to T transitions. Genetic studies presented here reveal a role for yeast Poleta in the error-free bypass of cyclobutane dimers and (6-4) photoproducts formed at CC and TC sites. Thus, by preventing UV mutagenesis at a wide spectrum of dipyrimidine sites, Poleta plays a pivotal role in minimizing the incidence of sunlight-induced skin cancers in humans.

A case report on vesico-uterine fistula: a very rare complication of the lower caesarean section

Vesico-uterine fistula is a very rare complication of lower caesarean section. There has only been two cases seen at the Department of Urology in the past 2 decades. Patients usually present in the early post operative period with the problem of continuous urinary incontinence. On the rare occasion, recurrent urinary tract infection, recurrent gross painless haematuria, or secondary infertility associated with secondary amenorrhoea would be the presenting complaint.

Characterization of the distal tail fiber locus and determination of the receptor for phage AR1, which specifically infects Escherichia coli O157:H7

Phage AR1 is similar to phage T4 in several essential genes but differs in host range. AR1 infects various isolates of Escherichia coli O157:H7 but does not infect K-12 strains that are commonly infected by T4. We report here the determinants that confer this infection specificity. In T-even phages, gp37 and gp38 are components of the tail fiber that are critical for phage-host interaction. The counterparts in AR1 may be similarly important and, therefore, were characterized. The AR1 gp37 has a sequence that differs totally from those of T2 and T4, except for a short stretch at the N terminus. The gp38 sequence, however, has some conservation between AR1 and T2 but not between AR1 and T4. The sequences that are most closely related to the AR1 gp37 and gp38 are those of phage Ac3 in the T2 family. To identify the AR1-specific receptor, E. coli O157:H7 was mutated by Tn10 insertion and selected for an AR1-resistant phenotype. A mutant so obtained has an insertion occurring at ompC that encodes an outer membrane porin. To confirm the role of OmpC in the AR1 infection, homologous replacement was used to create an ompC disruption mutant (RM). When RM was complemented with OmpC originated from an O157:H7 strain, but not from K-12, its AR1 susceptibility was fully restored. Our results suggest that the host specificity of AR1 is mediated at least in part through the OmpC molecule.

Brief report: speed of information processing in children with insulin-dependent diabetes mellitus

OBJECTIVE

To determine whether children with insulin-dependent diabetes mellitus (IDDM) process information more slowly than children who do not have diabetes.

METHODS

We tested 31 children with early onset and longer duration of IDDM, 35 with later onset and briefer duration of IDDM, and 36 comparison children without diabetes. They were administered five tasks requiring rapid responding that assessed a range of cognitive processes.

RESULTS

On most tasks, children in the three groups were quite similar in the accuracy and speed of performance. Furthermore, for children in the diabetic groups, disease-related variables were unrelated to accuracy and speed of performance.

CONCLUSIONS

The results suggest that children with IDDM do not have a pervasive deficit in speed of information processing, although more circumscribed deficits in processing speed are possible.

Efficient and accurate replication in the presence of 7,8-dihydro-8-oxoguanine by DNA polymerase eta

Oxidative damage to DNA has been proposed to have a role in cancer and ageing. Oxygen-free radicals formed during normal aerobic cellular metabolism attack bases in DNA, and 7, 8-dihydro-8-oxoguanine (8-oxoG) is one of the adducts formed. Eukaryotic replicative DNA polymerases replicate DNA containing 8-oxoG by inserting an adenine opposite the lesion; consequently, 8-oxoG is highly mutagenic and causes G:C to T:A transversions. Genetic studies in yeast have indicated a role for mismatch repair in minimizing the incidence of these mutations. In Saccharomyces cerevisiae, deletion of OGG1, encoding a DNA glycosylase that functions in the removal of 8-oxoG when paired with C, causes an increase in the rate of G:C to T:A transversions. The ogg1Delta msh2Delta double mutant displays a higher rate of CAN1S to can1r forward mutations than the ogg1Delta or msh2Delta single mutants, and this enhanced mutagenesis is primarily due to G:C to T:A transversions. The gene RAD30 of S. cerevisiae encodes a DNA polymerase, Poleta, that efficiently replicates DNA containing a cis-syn thymine-thymine (T-T) dimer by inserting two adenines across from the dimer. In humans, mutations in the yeast RAD30 counterpart, POLH, cause the variant form of xeroderma pigmentosum (XP-V), and XP-V individuals suffer from a high incidence of sunlight-induced skin cancers. Here we show that yeast and human POLeta replicate DNA containing 8-oxoG efficiently and accurately by inserting a cytosine across from the lesion and by proficiently extending from this base pair. Consistent with these biochemical studies, a synergistic increase in the rate of spontaneous mutations occurs in the absence of POLeta in the yeast ogg1Delta mutant. Our results suggest an additional role for Poleta in the prevention of internal cancers in humans that would otherwise result from the mutagenic replication of 8-oxoG in DNA.

Microscopic assessment of pronuclear embryos is not definitive

The microscopic classification of embryos, especially unipronuclear embryos, is not very precise. A number of undocumented and unipronuclear embryos were determined to be diploid following karyotyping and fluorescence in situ hybridization (FISH). Accelerated and asynchronous pronuclear dismantling at the time of checking for embryo fertilization accounts for this disparity. Diploid embryos were also observed among tripronuclear embryos. However, not all embryos ascertained as diploid by FISH were karyotypically normal following full karyotype analysis. By taking into account the "background" abnormality rate, the rate of diploid embryo wastage was estimated to be about 40% among undocumented embryos and about 58% in total. A high percentage of misclassification infers an unintended loss of otherwise transferable embryos. Such a discrepancy is particularly important to older women who have fewer embryos. If these are a woman's only embryos, preimplantation genetic diagnosis might be applicable in determining those that are diploid and suitable for transfer. This could potentially reduce the number of wasted embryos and cycles. The present study has also shown that mosaicism is common but it is still unclear whether mosaicism is indicative of embryonic abnormality or is a fairly common phenomenon among healthy embryos. Bipronuclear embryos that present with abnormal or delayed cleavage are often chaotic in their chromosomal constitution. Such embryos should not be transferred.

Percutaneous epididymal sperm aspiration in a man with congenital bilateral absence of the vas deferens undergoing an assisted reproduction program

Surgical retrieval of spermatozoa for in-vitro fertilisation (IVF) programs for severely oligospermic men has been in use for several years now. In the recent 2 to 3 years, clinicians have begun to move towards non-surgical methods of retrieving sperm in certain selected groups of men. Percutaneous epididymal sperm aspiration (PESA) has had good results in terms of number of sperm obtained, as well as the fertilisation and pregnancy rates. The first reported use of such a technique in Singapore is described.

Requirement of yeast SGS1 and SRS2 genes for replication and transcription

The SGS1 gene of the yeast Saccharomyces cerevisiae encodes a DNA helicase with homology to the human Bloom's syndrome gene BLM and the Werner's syndrome gene WRN. The SRS2 gene of yeast also encodes a DNA helicase. Simultaneous deletion of SGS1 and SRS2 is lethal in yeast. Here, using a conditional mutation of SGS1, it is shown that DNA replication and RNA polymerase I transcription are drastically inhibited in the srs2Delta sgs1-ts strain at the restrictive temperature. Thus, SGS1 and SRS2 function in DNA replication and RNA polymerase I transcription. These functions may contribute to the various defects observed in Werner's and Bloom's syndromes.

Effect of dehairing operations on microbiological quality of swine carcasses

To develop a hazard analysis and critical control point plan for food processing operations, critical control points must be determined. Swine slaughtering and dressing operations were investigated to establish their critical control points. We monitored the microbiology of swine carcasses by surface swabbing carcass bellies at various steps during the process and by quantitating total aerobic plate count (APC) and coliforms. Starting with a dehaired carcass, the sequential steps monitored included presingeing, postsingeing, polishing, and chilling. Initial results indicate that singeing and chilling substantially reduced the levels of APC and coliforms, whereas polishing increased their levels. The hygienic characteristics of individual operations involved in dressing swine carcasses were then evaluated in the second experiment. A set of 40 randomly selected carcasses leaving singeer, polisher, shaver, and washer were sampled. Carcasses were heavily contaminated during the final polishing procedure, and the APC increased threefold compared with prepolishing levels. Washing reduced the bacterial numbers by 69%. To reduce the microbial load on swine carcasses, final polishing and manual shaving steps were not used during the dressing operation on a set of 90 carcasses. APCs on singed carcasses were reduced from 1.34 to -0.15 log10 CFU/cm2 when the final polisher and manual shavers were not used. However, carcasses were subsequently recontaminated with bacteria after evisceration, and the APCs were similar (P > 0.05) regardless of whether the final polishing and manual shaving steps were used, averaging 1.30 and 1.46 log10 CFU/cm2. These results indicated that individual operations can be identified as critical control points, appropriate limits can be set and monitored in a hazard analysis and critical control point system, and steps where further changes to reduce bacterial levels may be needed for swine slaughtering plants.

Characterization of mouse peroxiredoxin I genomic DNA and its expression

Peroxiredoxins (Prxs) are a newly defined family of anti-oxidant proteins that have been implicated, via their anti-oxidant activity, in a number of cellular functions, including cell proliferation and differentiation, protection of other proteins from oxidative damage, and intracellular signaling. We isolated genomic DNA sequences of the Prx I genes from the mouse, and characterized their molecular genetic features. Prx I was found to form a small gene family with two and three members; one functional and two pseudogenes. The Prx I-1 gene has splice donor/acceptor site sequences and five or six exons, whereas the Prx I-2 clone has several structural features characteristic of a typical retroposon found to have ORF sequences. We analyzed the expression of pseudogenes, which were not expressed on the transcription levels in the investigated organs. The functional copy of the Prx I-1 gene was expressed abundantly in liver and kidney of the adult, as well as in early developing embryos. This report, together with amino acid/nucleotide sequence similarity between human and mice, provides a basis for speculating on an even earlier event in the evolution of the Prx I gene family, i.e. the Prx I gene was well conserved in human and mice via its anti-oxidant activity.

Organization of HIV-1 pol is critical for Pol polyprotein processing

The HIV pol sequentially encodes protease (PR), reverse transcriptase (RT), and integrase (IN) from the 5'-3' direction. We explored the significance of this gene arrangement. All six possible gene dispositions were examined. In two situations where PR was removed from the leading place and no two genes were in their original location, viral polyprotein processing was abolished. Processing of the polyprotein did not occur when IN was translocated to the front of PR-RT. However, in the following two arrangements, the polyprotein was processed but only at specific sites. First, PR remained in the leading position while the locations of RT and IN were exchanged; viral polyprotein was processed at a site between the upstream transframe peptide (TF) and PR. Second, PR was placed after RT-IN and located at the distal end of Pol. Processing occurred only at the created junction between TF and RT. These results indicated that cleavage after TF occurred autocatalytically but did not proceed to a second site, which needed an extraneous PR for trans-action. Therefore, arranging Pol in the order of PR-RT-IN warrants the streamline processing of the polyprotein once the autocleavage is initiated.

Characterization of the murine gene encoding 1-Cys peroxiredoxin and identification of highly homologous genes

A new type of peroxiredoxin, named 1-Cys peroxiredoxin (1-Cys Prx), reduces hydrogen peroxide with the use of electrons from unidentified electron donor(s). We have isolated the mouse gene encoding 1-Cys Prx (CP-3) and shown that it is comprised of five exons and four introns. Analysis of 5' flanking regions revealed binding sequences of several putative transcription factors such as Sp1, Pit-1a, c-Jun, c-Myc and YY1. It is noticeable that several potential Sp1 binding sites assigned the -60 through -96bp from putative transcription initiation site. The gel shift assays showed that Sp1 and Pit-1a bind specifically to each binding site in 1-Cys Prx promoter. We also isolated two highly related genes such as CP-2 and CP-5. These genes are encoded by single exons, and show 85% of nucleotide sequence homology with the CP-3. The structural features of these genes suggest that they might be intronless genes derived from the CP-3 by the mechanism involving retrotransposition. In addition, our data suggest that they are inserted to a specific site of the mouse L1 repetitive element. The 1-Cys Prx was actively transcribed in a variety of adult tissues as well as in the developing embryos. These results suggest that only the 1-Cys Prx gene might be relevant for studying the function of the 1-Cys Prx in the murine system.

Incidence of hepatocellular carcinoma in transgenic mice expressing the hepatitis B virus X-protein

BACKGROUND/AIMS

Chronic infection with hepatitis B virus is a high-risk factor for hepatocellular carcinoma in humans. The HBV X-protein, a multi-functional viral regulator, has been suspected to play a positive role in hepatocarcinogenesis, as demonstrated by the high incidence of hepatocellular carcinoma in HBx-expressing transgenic mice, although it is still controversial. The aim of this study was to generate transgenic mice expressing the HBV X-gene under authentic promoter control and to test whether the gene products can cause hepatic tumors.

METHODS

Three transgenic mouse lines were generated by microinjecting the X-gene construct into hybrid (C57BL/6 x DBA) eggs. Gene expression was tested by protein and mRNA analyses. During an observation period of 18 months, mice were sacrificed and organs subjected to histologic examinations.

RESULTS

Grossly defined hepatocellular carcinomas reproducibly were observed in mice expressing the X-protein, which were investigated through six generations from the age of 11 to 18 months. Among 14 transgenic mice investigated from the age of 11 to 18 months, 12 were found to have hepatocellular carcinoma, grossly or microscopically. The lesion of the hepatocellular carcinoma disclosed a significant increase in the proliferating cell nuclear antigen in the nuclei.

CONCLUSION

The incidence of hepatocellular carcinoma (86%) in our HBV X transgenic mice may be highly significant, since, except for one case, HBV X-gene transgenic mice produced in other laboratories did not develop liver tumor or any other pathologic phenomena.

Analysis of the sex chromosome constitution of sperm in men with a 47, XYY mosaic karyotype by fluorescence in situ hybridization

OBJECTIVE

To determine the incidence of sex chromosome aneuploidy in the sperm of two men with a 47,XYY/46,XY karyotype.

DESIGN

Case report.

SETTING

Infertility clinic in a teaching hospital.

PATIENT(S)

One patient with near normal semen parameters whose wife had a history of miscarriages and one patient with primary infertility and severe oligoasthenozoospermia.

INTERVENTION(S)

Cytogenetic analysis of peripheral lymphocytes and three-color X/Y/18 fluorescence in situ hybridization analysis of sperm.

MAIN OUTCOME MEASURE(S)

Analysis of sex chromosome disomy and diploidy rates in sperm.

RESULT(S)

Both patients had a 47,XYY/46,XY karyotype. The hyperdiploidy rate of patient 1 was 19% and that of patient 2 was 90%. The incidence of disomy XY was significantly elevated in both patients compared with the controls (0.23% and 1.02%, respectively, versus 0.10%). The incidence of disomy YY (0.44% versus 0.10%) was increased only in patient 2, as was the incidence of disomy 18 (0.49% versus 0.09%) and the rate of diploidy (0.83% versus 0.13%). The rate of 24,XX sperm in both patients was not different from that in the controls.

CONCLUSION(S)

Patients with a 47,XYY mosaic karyotype may be at risk of producing offspring with a hyperdiploid sex constitution. These patients should have their sperm investigated by fluorescence in situ hybridization to determine their particular risks before they undergo intracytoplasmic sperm injection.